\^' i> fk^^J %M i» p^.. • * t. THE LONDON AND EDINBURGH PHILOSOPHICAL MAGAZINE AND JOURNAL OF SCIENCE. CONDUCTED BY SIR DAVID BREWSTER, K.H. LL.D. F.R.S. L. & E. &c. RICHARD TAYLOR, F.L.S.G.S. Astr.S.Nat.H.Mosc.&c. AND RICHARD PHILLIPS, F.R.S. L.&E.F.G.S. &c. " Nee aranearum sane textus ideo melior quia ex se fila gignunt, nee noster vilior quia ex alienis libamus ut apes." Just. Lips. Monit. Folit. lib. i. cap. 1. VOL. XIL NEW AND UNITED SERIES OF THE PHILOSOPHICAL MAGAZINE, ANNALS OF PHILOSOPHY, AND JOURNAL OF SCIENCE. JANUARY— JUNE, 1838. LONDON: PRINTED BY R. AND J. E. TAYLOR, RED LION COURT, FLEET STREET sold by longman, orme, brown, green, and longmans; cadellj baldwin and cradock; sherwood, gilbert, and piper; simpkin and marshall; whittaker and co.; and s. highley, London: — by adam and charles black, and thomas clark, edinburgh ; smith and son, glasgow; hodges and smith, dublin ; and g. w. m. reynolds, paris. The Conductors of the London and Edinburgh Philosophical Magazine have to acknowledge the editorial assistance rendered them by their friend Mr. Edward W. Brayley, F.L.S., F.G.S., Corr. Mem. Roy. Geol. Soc. of Cornwall, Hon. Mem. S. Afric. Inst. ; Librarian to the London Institution. CONTENTS OF VOL. XIL NUMBER LXXI. and LXXIL— JANUARY, 1838. Page C. Despretz's Researches on the Maximum Density of Liquids 1 Mr. J. Tovey's Continuation of Researches in the Undulatory Theory of Light; — On the Cause of Elliptical Polarization 10 Mr. A. Kennedy's Observations upon the CEconomy of several Species of Hymenoptera found in a Garden at Clapton .... 14 Mr. G. Bird's Observations on induced Electric Currents, with a Description of a Magnetic Contact-breaker 18 Sir D. Brewster on a singular Development of Polarizing Structure in the Crystalline Lens after Death ; and on the Cause, the Prevention, and the Cure of Cataract 22 Mr. R. Hunt on Tritiodide of Mercury 27 Mr. J. Watson on a simple Mode of exhibiting the Colours of thin Plates 28 E. Simon of Berlin, on Jervine, a new Vegetable Base 29 Mr. R. Rigg on a Method of analysing Organic Compounds. . 31 Dr. H. Falconer, and Capt. P. T. Cautley on additional Fossil Species of the Order Quadrumana from the Sewalik Hills . . 34 Notice of additional Fragments of the Sivatherium 40 Lieut. -Col. A. Emmett's Meteorological Observations for Por- tions of the Years 1836 and 1 837, made at Bermuda ; and a Notice of an Aurora Borealis seen in low Latitudes 42 Mr. Lubbock on the Wave-surface in the Theory of Double Refraction 47 Mr. H. M. Noad on the peculiar Voltaic Conditions of Iron and Bismuth 48 Prof. J. Meyen's Report of the Progress of Vegetable Physio- logy during the Year 1836 53 Prof. J.J. Sylvester's Analytical Development of Fresnel's Op- tical Theory of Crystals 73 M. Walter's Notice on the Bichromate of the Perchloride of Chrome 83 Observations on the Meteors of the 1 2th of November. Com- municated by Prof. Forbes 85 Proceedings of the Geological and Linnsean Societies ; Royal Irish Academy, British Association for the Advancement of Science : Meeting of 1837, at Liverpool 86 New Books : — ^W. Leithead's Electricity; its Nature, Opera- tion, and Importance in the Phaenomena of the Universe . . 127 Absorption of Water by Efflorescent Salts 130 Detection of common Salt in Chloride of Potassium 132 New Acetate of Lead 133 Sulphuret of Azote 134 Xanthophylle, — the Colouring Matter of Leaves in Autumn . . 135 Detection of Metallic Chlorides in Bromides and Iodides, by M. Henry Rose 136 a2 IV CONTENTS. Page On the Employment of Metallic Sulphurets in Analysis, by Mens. E. F. Anthon 137 On the Fermentation of Sugar of Milk, by M. Hess 139 Formation of Nitre in Extract of Quassia, by M. Planche .... 140 Method of dissolving Iridium, by M. Fellenberg 141 On Lactic Acid in Sour-Crout, by M. Liebig 142 Meteorological Observations made at the Apartments of the Royal Society by the Assistant Secretary ; by Mr. Thomp- son at the Gardens of the Horticultural Society at Chiswick, near London ; and by Mr. Veall at Boston , . . . 143 NUMBER LXXin.— FEBRUARY. Mr. H. F. Talbot on a new Property of Nitre 145 The late Colonel Francis Hall's Meteorological Observations made during a residence in Colombia between the Years 1 820 and 1830 148 Dr. Dalton's Sequel to an Essay on the Constitution of the Atmosphere, published in the Philosophical Transactions for 1826 ; with some Account of the Sulphurets of Lime 158 Mr. Lubbock on the Divergence of the numerical Coeffi- cients of certain Inequalities of Longitude in the Lunar Theory 168 Dr. M. J. Schleiden's Observations on the Development of the Organization in Phsenogamous Plants 172 Mr. F. Watkins on Electro-magnetic Motive Machines 190 C. H. Matteucci's Physical, Chemical, and Physiological Re- searches relative to the Torpedo ; and some Remarks on the Contractions of the Frog 196 New Books : — Hood's Practical Treatise on Warming Build- ings by Hot Water, with some remarks on Ventilation ; — Curtis's Guide to an Arrangement of British Insects 202 Bibliographical Bulletin 203 Proceedings of the Royal Society, Zoological Society 204 Preparation of Protoxide of Tin 216 Preparation of Bicarbonate of Potash, by Prof. Woehler 216 New Locality of Arsenical Copper in Chili, by Von Zinken. . 217 Definite Combination of Oxide of Silver and Oxide of Lead, by Prof. Wcehler 217 A new Method of obtaining Chrome Alum, by R. F. Marchand 218 Examination of Malt liiquors, by Prof. Fiichs 218 On some new Compounds of Chlorine, by M. Heinrich Rose. . 220 New Acid formed by the Combustion of Alcohol around an in- candescent Platina Wire 220 On Gentianin, by M. Trommsdorff 221 On Quassin 222 Needles rendered magnetic by the Nerves 223 Meteorological Observations. 223 CONTENTS. V NUMBER LXXIV.— MARCH. Page Prof. Schoenbein on the mutual Voltaic Relations of certain Per- oxides, Platina, and inactive Iron 225 Mr. G. Bird's Observations on indirect Chemical Analysis 229 Mr. R. Rigg's further Observations on the ultimate Analysis of Organic Compounds 232 Mr. R. H. Brett's Analysis of some Double Salts of Mercury 235 Dr. M.J. Schleiden's Observations on the Development of the Organization in Phaenogamous Plants 241 Mr. J. Prideaux's Description of the Kauri or Cowdee Resin, from New Zealand, with Experiments in Relation to its Em- ployment in the Arts 249 Mr. Lubbock on the Variation of the Arbitrary Constants in Mechanical Problems 254 M. Ch. Matteucci's Chemical Analysis of the Substance of the Electrical Apparatus of the Torpedo 256 Mr. H. F. Talbot on a new Property of the Iodide of Silver . . 258 Mr. J. Tovey on Professor Sylvester's Analytical Development of Fresnel's Optical Theory of Crystals 259 Prof. Johnston on the Composition of certain Mineral Sub- stances of Organic Origin. 1. Middletonite 261 New Books ; — James Macfadyen's Flora of Jamaica 263 Proceedings of the Royal, Royal Astronomical, Geological, and Meteorological Societies 269 Note omitted in Dr. Schleiden's Paper 292 On the Development of an Electric Current accompanying the Contraction of the muscular Fibre, by Dr. Prevost . . 293 On Thermo-electric Phsenomena, by Ch. Matteucci 295 On Cetrarin, by M. Herberger 296 Action of Chlorine on ^ther 297 Camphoric Acid 297 On the Colours of Metals, by Mons. R. Bottiger 298 On the Action of Protoxide of Iron on Protoxide of Copper . . 299 On the Gases contained in the Blood, and on Respiration, by M. G. Magnus 300 On the low Temperature of January 1838, by Mr. F. Watkins 302 Meteorological Observations 303 NUMBER LXXV.— APRIL. Dr. T. Andrews on the Action of Nitric Acid upon Bismuth and other Metals 305 Prof. Schoenbein's further Experiments on the Current Electri- city excited by Chemical Tendencies, independent of ordinary Chemical Action 311 Rev. B. Powell's Notice on Repulsion by Heat, &c 317 Mr. H. Giraud on the Nature and Properties of Teriodide of Chromium 321 Yl CONTENTS. Page Prof. De Morgan on the Relation between the Number of Faces, Edges and Corners in a Solid Polyhedron 323 Prof. J. F. W. Johnston on the received Equivalents of Potash, Soda and Silver 324 On the Path of the projectile Weapon of the Native Australians called the " Boomarang" or " Kylee" 229 Mr. A. Smith's Method of finding the Equation to Fresnel's Wave-Surface 335 Mr. T. Taylor's Description of two Calculi composed of Cystic Oxide 337 Prof. J. F. W. Johnston on the Composition of certain Mineral Substances of Organic Origin. 2. Hatchetine 338 MM. Pelouze and Richardson's Researches upon the Products of the Decomposition of Cyanogen in Water 339 Prof. J. J. Sylvester's Notes to Analytical Development, &c.. . 341 Mr. G. B. Jerrard on the Occurrence of the form g in passing from general to particular Values of certain Algebraic Func- tions 345 Proceedings of the Ptoyal Society, and Royal Irish Academy . . 347 New Books : — H. C. Agnew's Letter from Alexandria on the Evidence of the practical Application of the Quadrature of the Circle in the Configuration of the Great Pyramids of Gizeh 379 Improvements in Magnetical Apparatus by the Rev. W. Scoresby 380 On the Constitution of some Organic Acids, by M. Dumas and M. Liebig 381 Meteorological Observations 382 NUMBER LXXVI.~MAY. Remarks on " A singular Case of the Equilibrium of incom- pressible Fluids ; by M. Ostrogradsky" 385 Prof. J. F. W. Johnston on the Dimorphism of the Chromate of Lead 387 Prof. J. F. W. Johnston on the Composition of certain Mineral Substances of Organic Origin. 3. Ozocerite 389 Dr. Dalton's Sequel to an Essay on the Constitution of the Atmosphere published in the Philosophical Transactions for 1826 ; with some Account of the Sulpliurets of Lime .... 397 Mr. Brooke's Note on an apparent Case of Isomorphous Sub- stitution 406 Mr. R. Phillips's Observations on Isomorphism, in reference to the preceding Communication by Mr. 6rooke 407 Mr. T. Taylor's Observations on Urinary Calculi 412 Mr. D. Cooper on the Luminosity of the Human Subject after Death ' 420 Proceedings of the Royal, Geological, and Zoological Societies ; of the Royal Institution, and the Cambridge Philosophical Society . .' , 426 CONTENTS. VU Page Gresham College : Prof. Pullen's Lectures on Astronomy .... 454 On the Influence of Heat, &c. on the Circulation of the Chara 457 Oxalo-Nitrate of Lead 459 Action of Iron at a high Temperature on Benzoic Acid : Benzin 460 Action of Iron at a high Temperature on Camphor 460 On Chloride of Tungsten, by M. Heinrich Rose 461 Fall of Meteoric Stones in Brazil 462 On the Adulteration of Carmine, by C. G. Ehrenberg 462 Meteorological Observations 463 NUMBER LXXVIL— JUNE. Gustave Rose on the Formation of Calc Spar and Arragonite 465 Prof. R. Hare's Observations on Sulphurous ^ther, and Sul- phate of ^therine (the true Sulphuric ^ther) 474 Prof. Johnston on a supposed Analogy in Atomic Constitution between the Earthy Carbonates and Alkaline Nitrates 480 Mr. Potter's Reply to the Observations of J. H. Wheeler, Esq., on the Method of computing the Results of Experiments with the Comparative Photometer 484 Mr. Laming on the primary Forces of Electricity. 486 Mr. J. Hogg's Specimen of a Thermometrical Diary kept abroad in the Years 1824, 1825, and 1826; and compared with a corresponding one made in London during the like Period 498 Mr. T. Wright's Observations on Dr. Buckland's Theory of the Action of the Siphuncle in the Pearly Nautilus 503 Proceedings of the Geological, Royal Astronomical, Zoological, and Linnsean Societies ; of the Royal Institution : Friday Evening Meetings : Mr. Brayley on the Theory of Volcanos. . 508 New Books : — Description d'une Collection de Miner aux, form^e par M. Henri Heuland, et appurtenant d, M. C. H, Turner. ... 536 On the Electrical Currents produced during the Processes of Fermentation, by Mr. J. Blake 539 On the Decomposition of Water by Thermo-Electricity, by Mr. F. Watkins 541 Discovery of the North-west Passage, under the Instructions of the Hudson's Bay Company, by Messrs. Dease and Simp- son 542 African Discovery 543 Meteorological Observations 543 NUMBER LXXVIII.— SUPPLEMENT. Prof. Forbes's Researches on Heat. Second Series 545 Prof. Johnston on the Composition of certain Mineral Substances of Organic Origin 560 Proceedings of the Geological, Zoological, and Meteorological Societies 564 Viii CONTENTS. Page New Books : — J. R. Young's Analytical Geometry 602 Tartaric and Paratartaric Acids, etc 605 M.T. de Saussure on the Action of Fermentation on a mixture of Oxygen and Hydrogen Gases 607 The Action of Sulphate of Ammonia upon Glass 608 Index 609 PLATES. I., and II. Illustrative of Dr. Falconer and Capt. Cautley's Paper on Fossil Quadrumana, and of Col. Colvin and Mr. Peinsep's Notice of additional Fragments of the Sivatkerium. III. and IV. Illustrative of Dr. Schleiden's Memoir on the Develop- ment of the Organization in Phaenogaraous Plants, and of Mr. F. Watkins*s Paper on Electro-magnetic Motive Machines. ERRATA. Page 12, equations {7) for n in both places read n,,. Page 13, line 21,/or (1 — - sin {71, t — kx)) read (1 -- sv^?{n^ t — kx). Page 46, line 5, /or latter read former. 23 /or -?r read t. ar a^ Page 28, 29, for Walgon read Watson. We have been kindly furnished by Dr. Schleiden with the following errata which occur in the translation of his paper. Page 175, line 6, for their points, read the extreme point of the axis Ibid, in the note, line 6, the plumula in this family becomes envelopedhy means of an elevation of the cotyledon perfectly closed Page 177, line 4, after disproportionately large, — what in the expanded flower has been called pale« sin (nt—kx-^b) ; then A )) = a sin {n t — k x — k A jf) — a sin{w^ — ^ jr) = fl5(cos/i: Ax— 1) sin {nt^kx) — as'mk^x cos {nt—kx)-. also, A), = a sin {nt—kx — h—k£^x-\-b)'-a sin {nt—k x—b^b) = a {cos(^A^ — 6)-— cos^} sin {nt^kx^b) — a {sin (^Aar— 6)-f sinij. co%{nt — kx—b). In like manner we find, A? = pflsin {nt—kx—b — k ^x)—f)a sm{nt—kx — b) = pa (cos^ Ax — l) sin [ni—kx^b)— p a sin k i^xcos [nt—kx—b) : also, A? = pa {cos(^ Aa: + Z>)— cos/;} sin (;?/—^.r) — pa {sin {k ^x-\-b)—smb^ cos {nt—kx). Now put m 5'. {4)(r)+^Kr) Aj/«} (cos ^Ax— 1) = 5, 7W X. {4> (r) + ^Kr) A2^} (cos^A.r-1) = 5', m S. {^{r) + ^{r)Af} sin^Ao- = s^, mS,{{r)+^(r)Az''}sinkAx=:s\, m H ,^ (r) At/ Az { cos (k A x — b) — cos b] — s^y VI X.^ (?•) At/ A z { cos (k A X -{-b) — cos b} = s'^ , 7n X .^ (r) Aj/ Am {sin (A: A j:— />) + sin />} = ^3, mS ,^ (r) A 2/ A 2 {sin (A: A ,2? + ^)-- sin ^} = s'.^; and substitute, in the equations (1.), the values of jj, ?, Arj, A ? ; C2 12 Mr. Tovey's Researches in the Undidatory Theory: taking, for the first equation, the values of A t) and A ? which involve the arc {nt — kx), and for the second equation, the values involving \n t—kx—b). We shall then have («« + 5H-ps'2) sin {nt-k x)—(s,-\- p s'^ cos{nt-k x) = 0, (p[n^^^)-\-s^)sm{nt''kx—h)-{ps^^\■s.^)cos{nt — kx-'b)=0\ and since these equations are true for all values of / and x^ they resolve themselves into 71^ + 5 + ^52 = 0, p(w^+s')+52= 0, ,, V ^5/ + .93 = 0. These equations may be satisfied by means of the four ar- bitrary quantities n, p,k,b\ the last two being contained in them implicitly. From the first and second of these equations we derive Let .,.^ 4 then the two values of n^ will be n^ =z — s— s, W/« = - 5' + « ; (5.) and those of p f. = ^. P.= -^- (6-) These values being substituted in the assumed expressions for >) and ?, we have >j = a^ sin (n^ t—k x) + a^^ sin {n t—k x) , .^ x i^^=p^a^sm{n^t — kx—b)+p^Ja^^{nt — kx^—b), ^ '^ It has been seen (at p. 501 of your 8th vol.) that any func- tion of X and t may be expressed by a series of which each term has the form {psmk x -^-q coskx) ; where p and q are functions of t, and k a constant quantity. P'or the same rea- son any function of t may be expressed by a series, each term having the form A sin w ^ + B cos n t^ where t is the only variable. Therefore, iot [p ^m k x-^q cos k x) we may write ( A sin w ^ + B cos w /) sin A: or + { A sin w ^ + B cos n t) cos k x, which, by the rules of trigonometry, may be reduced to the ^o™ asin{nt--kx'-b) + a'sm{nt-^kx'-b^); On the Cause of Elliptical Polarization. IS and this, when the waves move only in the direction of x po- sitive, becomes ^ gin {nt-kx^b). Now the equations(l.) being of the first degree, may be satis- fied not only by the second members of the equations (?.)» but by the sum of any number of functions of the same form. It follows, therefore, from the observations just made, and from the circumstance that the origin of x is arbitrary, that the complete integrals of the equations (1.) may be expressed by yi— X {a^s\n (njt—kx) + «^^ sin (n^^t—kx)} , ^ = :§' {pia^s\n{nit — kx — b)-^p^^aiiSin{nfit—kx—b)}: ^ '^ provided that the waves travel in the direction of x positive, and that the displacements ij and ^ are functions of x and t. Suppose the arbitrary coefficients in the equations (8.) to be all zero except a^ , then >j = a^ sin {n^t-kx), . . ^ = p^ a, sin (n^t—k x—b) ^ '' = p^a^ {sm {n^t— k x) cos b-^smb cos {n^t—kx)} ', therefore (J— Pi «; sin (n^t-^kx) cosbf =z p^^ a^'^ sin^bcos^ {n,t—kx) = §/ a^* sin® b ( 1 — sin {n,t—kx)): hence we have an equation to an ellipse of which >j and ? are the coordinates. Consequently, when the system is in a state of motion which can be expressed by the equations (9.)> every molecule de- scribes an ellipse round its place of rest ; and the equations (8.) show that the general motion of the system is equivalent to a number of coexisting motions of the same kind. In a future paper I purpose to apply these formulae to the case of elliptical polarization produced by quartz crystaL I am. Gentlemen, yours, &c. Litdemoor, Clitheroe, Nov.24, 1837. John TovEY. P.S. To justify our neglect of the displacements f, it may be well here to observe, in addition to what has been re- marked (vol. ix. p. 421.) that when x is taken, as we have supposed, perpendicular to the wave- surface, neither the dis- placements >3, ^, nor their differences A>), A ?, cause any change of density in the medium; but the differences Af imply a change of density. If then we suppose the force by which 14 Mr. A. Kennedy's Observations upon the aether resists compression to be so great that in the mo- tions producing light it may be regarded as incompressible, the differences A ^ vanish, and the last two of our general equations (3.) of vol. viii., p. 9, become the same as the equa- tions (1.) of this paper. The reason assigned by Mr. Kelland (vol. ix. p. S^ 1 .) why the displacements ^are insensible, or, in other words, why there is no vibration in the direction of transmission, cannot, 1 conceive, be the true one; because it implies a state of unstable equilibrium. (See Pratt's Mechanical Philosophy, art. 508.) I believe the ingenious Fresnel considered the true reason to be the one which we have just supposed. in. Observations upon the (Economy of several Species of Hymeno}itera found in a Garden at Clapton, By A. Kennedy, Esq,^ p-TAVING had leisure this spring and summer to devote ^^ more time than usual to my favourite pursuit, entomo- logy, 1 have paid considerable attention to the oeconomy of various insects inhabiting a summer-house in my father's grounds, made of the stumps of trees, and having a thatched roof, which has afforded me much amusement from the num- ber of different species oi Hymenoptera which nidificate either in the posts or thatch. The following is a list of the insects I have observed, and I shall make a few remarks upon the ceconomy of each species, some of the facts relating to which I believe have not before been recorded. Fam. DiPLOLEPiDiE. 11. Pemphredon raorio, VanL. 1. Cratomus megacephalus, JF'. 12. unicolor, ia/. Fam. SAPYGiDiE. 13. Psenatratum, Pz. 2. Sapyga 4-guttata, F. Fam. Vespid^. 14. Odynerus quadratus, Don. Fam. Crabronid^. 15 bidens, L. 3. Trypoxylon figulus, Lat, „ A.— clavicemm, 5-^ i?'. ,^ „ , Fam. Andrenid^. 5. Crabro spinipectus. Shuck. ? ^^' "ylaeus signatus, Pz. 6. Stigmus troglodytes, Van L. Fam. kviDM. 7. Diodontus insignis, VanL. 17. Chelostoma florisomnis, L, 8. gracilis, Curt. 18. Osmia bicornis, L. 9. corniger, Shuck. 19. spinulosa, JC. 10. Pemphredon liigubris, F. 20. Heriades campanularum, K. 1. Cratomus megacephalus, Fab. I have observed four or five specimens of this insect settling • Commuiiicated by the Author. the (Ecofwrnj/ of several Species o/* Hymenoptera. 15 upon the posts of the summer-house, but I have not ascer- tained any thing of its oeconomy. 2. Sapyga Ai -guttata*^ Fab. The oeconomy of this insect, 1 believe, is not known. I have taken two or three specimens flying about tlie posts. The male is much rarer than the female. 3. TrypoxylonJlg2dus\y Lat. This insect entombs spiders for the supply of its young ones. I have often watched it carrying the spiders into holes in the posts, and also into straws in the thatch. On splitting open one of the latter I found a number of cells filled with spiders and separated from one another by partitions of clay. Between each cell, there was a space left of about a quarter of an inch, so that there were two partitions between each cell, and be- tween the last cell and the outside. There was one egg iii each cell attached to the abdomen of a spider near the bottom of the cell. The Trypoxylon sometimes buries very large spiders compared with its own size, so that it can hardly jam them into its hole. I was one day much amused with a male, who when the female was absent often came, entered, and remained at the entrance with his antennae just projecting as if he was keeping watch to keep out parasitical insects^ and once when I placed my hand over the hole so as to prevent the female entering, after repeated attempts she flew away, and returned with the male as if to ask his advice respecting the obstruction to her nest. The number of spiders in the cells of course differs accord- ing to their size, there sometimes being only two if very large, and sometimes as many as twelve or more if small. The Trypoxylon does not appear to be partial to any particular species. The female makes a buzzing noise when she is con- structing the clay partitions. I believe the oeconomy of this insect has never been distinctly ascertained before. 4. Trypoxylon claxncerumX^ St. F. The habits of this insect are similar to those of T.Jigulus^ only burying very small spiders, and not leaving any space between the cells. I believe that Mr. Shuckard and another gentleman are the only persons who have taken it besides myself. Its oeconomy has not been noticed before. 5. Crahro spinipectus, Shuck. ? The male of this insect is common about the posts of the summer-house, but I have not been able to discover the fe- male. • Curt. Brit. Ent., p. 532. f Ibid. p. 652, J Ibid. 16 Mr. A. Kennedy's Observations upon 6. Stigmus troglodytes. Van L. I have taken four or five females of this insect and one male. On the 22nd of July I saw a female enter a straw with its prey in its mouth, and on splitting the straw open I found a great many minute insects, which appeared to be the larvae of a Thrips, I should think there must have been at least fifty in one cell. There were two cells, separated from one another by partitions which appeared to be made of the scrapings of the inside of the straw cemented together. I also noticed a female with its prey enter a hole in one of the posts. I do not think the oeconomy of this insect has ever been noticed before. 7. Diodonttis insignis, Van L. The males of D, insignis were common about the summer- house from the beginning of July to the end of the same month, but 1 have not been able to find one female. 8. Diodontus gracilis^, Curt. The female supplies its young with aphides, which I have noticed it take from the leaves of the ivy. It makes its cells in the straws of the thatch, and separates them by partitions made apparently of the same materials as those o( D,corniger. I have not taken any males. 9. Diodontus corniger. Shuck. The male of this insect I first took on the 3rd of July, and the female on the 8th. The females were tolerably common towards the end of the month, but I have only taken six or seven males. The female provides aphides for the food of its young, and it appears to take them from the holes of other insects. I have often watched it entering holes in the posts and returning with aphides to its own hole. It carried them one by one in its mouth; and what was very curious, in going from its own to the other hole it ran straight along the post, but in returning with an aphis, although the holes were not half a foot apart, it flew off some distance before it conveyed its prey home. No other insect appeared to inhabit the holes from which it took the aphides. The partitions between each cell are made of a sticky transparent substance laid over with small fibres of wood. I have watched the female closing the orifice with the same material. After she had completely closed it with the propolis she went into another hole, and re- turned with small fibres of wood, which she plastered over, and this when dry became hard and strong. The habits of this insect have not been noticed by any one else, and I believe Mr. Shuckard is the only person who has taken it before myself. • Curt. Brit. Ent., pi. 49G. the (Economy of several Species of Hymenoptera. 1 7 10. Pemphredon lugubris, Fab. I have watched this insect burrow into the wood and throw out the saw-dust. It appears to prefer decayed wood for making its cells, in which it deposits aphides. 11. Pemphredon Morio, Van L. I am not quite certain whether I took this insect at the summer-house or not, but 1 think I did. 12. Pemphredon unicolor'*, Lat. The ceconomy of P. unicolor is, I believe, well known. I have taken it carrying an aphis, but have not examined its cells. 13. Psen atratumf, Pz. This insect has been exceedingly numerous this year, using the straws in the thatch to deposit its prey in, in some of which I have counted as many as a hundred aphide. The partitions appear to be made of the scrapings of the inside of the straw cemented together. The egg is wliiteand semitrans- parent, and is attached to the abdomen of an aphis near the bottom of the cell. The males first appeared the beginning of July, flying about the thatch and the neighbouring shrubs in thousands. They disappeared about the end of the month. The females did not become numerous until the 10th. 14. Odynerus quadratusX, Don. This insect entombs small green caterpillars having sixteen feet; six pectoral, eight abdominal, and two anal. On cutting open a post where I saw the female enter with its prey, I found a tunnel of about four inches in length running parallel with the sides of the post, and divided into three or four cells by partitions of clay. In each of these cells were about ten caterpillars closely packed, and a long white egg attached to the side of the cell near the bottom. I first noticed this insect the beginning of June, and it was abundant during the whole of that month. 15. Odynerus bidens, Linn. I observed a female of Odynerus bidens burrowing into a post the beginning of July, and a day or two afterwards I cap- tured her while conveying her prey, which appeared to be the larva of a Chrysomela, On opening the post the end of July I found a tunnel two inches in depth, divided into three cells by partitions of clay. In the first cell the Odyneius was in the pupa state, and in the two lower ones in that of larva. Each of the cells contained the remains of larvae, and in one of them was a small dipterous insect quite perfect. • Curt. Brit. Ent., pi. 632. f Ilnd., fol. 25. J Ibid., fol. 137. PhiU Mag, S. 3. Vol. 1?. No. 71. Jan, 1838. D 18 Mr. G. Bird's Observations on induced Electric Currents, 16. Hylarus signatus*, Pz. I noticed a female of this insect enter a straw in the thatch, and on spHtting it open I found at the bottom a quantity of some sweet substance, which I suppose was honey. It smelt exactly like the leaves of Verbena triphylla-y and what is re- markable, I have taken many of the insects which had the same smell themselves, particularly when crushed. Yet 1 can- not think that they obtained it from that plant as we have none in the garden. 17. Chelostoma florisomnis\, Linn. On the 5th of June I watched this insect boring into one of the posts and throwing out the saw-dust with her hind legs. On the 6th she had finished boring and was collecting the pollen and honey to deposit her eggs in. I also watched her bringing small pellets of clay in her mouth to form the parti- tions. This continued until the 30th, when she closed the orifice with clay and small stones. There are generally eight or ten cells in the tunnels nearly filled with pollen, &c. ; and the egg^ which is long, white and semitransparent, is deposited in the midst at the top. The males I took flying about the posts where the females nidificated. 18. Osmia bicornisX^ Linn. The oeconomy of this bee seems nearly similar to that of the last. It is found about the same time, but the males ap- pear some time before the females. 1 9. Osmia spinulosa, Kirb. This bee forms a paste of pollen, &c. for its young, appa- rently similar to bicornis, but the partitions are of a green co- lour, and seem to be made of clay and the parenchyma of leaves kneaded together. 20. Heriades campanidarum §, Kirb. I have taken this insect settling upon the posts of the sum- mer-house, but have not observed any thing of its oeconomy. Upper Clapton, Aug. 22, 1837. A. Kennedy. IV. Observations on induced Electric Currents, with a Descrip- tion q/' a Magnetic Contact-breaker. By Golding Bird, F.L.S.,F.G,S., 6)C,,Lccturer on Experimental Philosophy at Guy's Hospital, SfC; in a Letter to Richard Phillips, Esq. F.E.S., 4c My dear Sir, NE of the most important of the very numerous discoveries of Dr. Faraday is undoubtedly that of electrodynamic • Curt. Brit. Em., fol. 373. f Ibid., fol. 628. t Ibid., fol. 222. § Ibid., fol. 504. o mth a Description of a Magnetic Contact-breaker. 19 induction, by wliich we are enabled to render the electricity naturally present, but previously latent, in a coil of wire, ob- vious, by allowing a current from a small voltaic pair to circu- late through a second coil placed in a direction parallel to the first. Perhaps the best mode for effecting this is the follow- ing, which my own experiments have induced me to adopt: Wind on a reel with a hollow axis, three inches in length, about 60 feet of copper wire -^^ inch in diameter, covered with cotton thread for the purpose of insulation. Allow the two ends of the wire to project from the reel, and call them A and B. Over this coil, wind a second insulated copper wire -^-Q inch in diameter and about 1500 feet in length; let the two ends of this second coil be called C and D. It is now evident from the law of electro-dynamic induction that on connecting the ends A and B of the thick coil with a single pair of plates, a current of electricity is set in motion in the thin coil ; and on breaking contact, a second current in another direction traverses the same coil, sufficient in intensity to communicate an energetic shock to any person grasping the ends C and D of the long helix ; and by very rapidly break- ing contact a rapid series of intense shocks may be communi- cated to any conducting body connecting the ends C and D. As it is exceedingly inconvenient to effect the rupture of contact with the battery by raising the end of the thick coil with the hands, various modes have been proposed, depend- ing all however upon the same principle, viz. that of a spring pressing against a revolving cog wheel, or some modification of this arrangement. These instruments all present the same objection, that of the hands of the operator being employed in turning a wheel for the purpose of breaking contact when they are required elsewhere to direct the induced current through any conducting body he pleases; this difficulty may, it is true, be obviated by causing an assistant to turn the wheel, but even this is highly inconvenient when currents are required for electrolytic purposes during half an hour, or even a less space of time. For these reasons, together with many others depending upon the irregular rotation of a cog-wheel, I have disused instruments depending upon this principle for the last ten months, and have adopted one which appears to me to be quite free from the above objections, and is certainly an ex- ceedingly simple and convenient one, by the aid of which a series of induced currents may be passed through any con- ducting body for almost any length of time. This instrument consists of a base-board about eight inches in length and three in breadth, furnished at both ends with a D2 20 Mr. G. Bird's Observations on induced Electric Currents z piece of hard wood, A and B, each having two holes excavated in it for the purpose of holding mercury: each of these holes communicates by means of thick copper wires, D D\ with that opposed to it in the other piece of wood at the opposite end of the board. Midway between these receptacles for mercury is a wooden support, so contrived that a piece of soft iron wire J inch in diameter and 5 inches in length may oscillate be- tween the cheeks cut in its upper part, with as little friction as possible, the iron wire being supported by milled-headed screws. Around this iron wire E F, are wound two helices of thin insulated copper wire, in the same direction, (from right to left,) in such a manner that the two ends of one helix may terminate in the copper points G H, and the ends of the other helix in the points K L. Two small horse-shoe mag- nets (not shown in the figure) are then fixed on proper sup- ports, so that they may each be placed near an end of the iron bar E F in a vertical plane just posterior to it, so that on depressing the end F of the bar it may be opposite one pole (say the south) of one magnet, and consequently the end E will be opposite the other pole of the second magnet. On elevating the end F, the contrary will of course take place, and for this purpose it is hardly necessary to say that the similar poles of the magnets should be in the same direction. From this description it is evident, that on connecting the cups of mercury in A or B with the two plates of a single voltaic battery, the bar E F will become a temporary magnet if the ends of either helix are allowed to dip in the mercury ; and if connection with the battery is properly made, the ends or poles of the temporary magnet will be repelled by the poles of the permanent magnet to which they are opposed ; the bar will consequently move, and so cause the immersion of the ends of the second helix in the other cups of mercury, repulsion will again occur, and so on : about 300 oscillations of the iron bar can be thus obtained in a minute. On connecting the ends of the thick helix of the coil before described by tlie battery isoith a Description of a Magnetic Contact-hrcaher. 21 of a single pair by means of this apparatus, a series of in- duced currents may be obtained from the extremities of the longer helix capable not only of communicating a series of intense shocks, but of exerting powerful electrolytic action. This connection is best made in the manner shown in the ac- companying figure, in which R represents a section of the reel, 8 one end of the short helix connected with a cup of mercury in the piece of wood B, Z the other end of the short helix connected with one plate of the battery, whilst the wire C connects the other cup of mercury in B with the other plate of the voltaic couple. It is scarcely necessary to state that the intensity of the induced current may be increased by inserting in the hollow axis of the reel a bar of very soft iron, or what will be still better, a bundle of soft iron wire, which becoming magnetic, will considerably increase the dynamic power of the coil. In this case, indeed, the sparks produced when the ends of the helices round the iron bar E F leave the mercury are very brilliant, accompanied by a loud snap- ping noise and a vivid combustion of the mercury, clouds of the oxide of that metal being copiously evolved. If the ends P R of the long and thin coil are furnished with platinum points and immersed in water acidulated with sul- phuric acid, rapid electrolytic action ensues, torrents of minute bubbles of oxygen and hydrogen being evolved. If instead of water the points are pressed upon paper moistened with iodide of potassium, electrolytic action ensues*, iodine and oxide of potassium being separated. Solutions of sulphate of potass and soda, chloride of potassium, sodium, antimony and copper are also rapidly decomposed. In these experi- ments it will be found that the great majority of the electro- positive elements (for example) appear constantly at one ter- mination of the coil, cceteris paribus^ but not all, for it must not be forgotten that on making as well as breaking contact with the electromotor an induced current takes place in the long coil, although of far weaker intensity than the latter, to which it is opposed in direction, and consequently in electro- lytic effects. If the ends P R of the long coil are furnished with copper cylinders for handles and then grasped even with the un- • If whilst the oscillating bar of the contact-breaker is vibrating rapidly, we fix a piece of well-burnt charcoal on one of the terminations of the fine coil, and draw the other termination lightly over it, a rapid succession of minute but brilliant sparks are obtained. These sparks depend entirely upon the induced current, as the fine coil has no connection with the electromotor. For the exhibition of this, as well as of the electric light of an energetic arrangement, I find pencils of that kind of artificial gra- phite found lining the interior of the iron cylinders used for the distillation of coal in otir gas manufactories very far superior to box-wood, or indeed any other form of charcoal. 23 Sir D. Brewster on a singular Developitient of moistened hands, the intensity of the rapid succession of shocks will be found absolutely intolerable, even when the battery used consists of but two plates presenting each 6 or 8 square inches of surface. This magnetic contact-breaker will, 1 flatter myself, be found eventually of service to the chemist for electrolytic purposes ; whilst as affording a ready mode of applying voltaic electricity for medical purposes, I think it will be considered of con- siderable service as dispensing with manual labour, and afford- ing currents ot far greater intensity than can be obtained from several dozen, or even a far greater number of pairs of plates excited by strong acids, a process equally inconvenient and expensive. In conclusion, I ought to observe that the application of a permanent magnet to effect the rupture of contact without manual labour is by no means original with me, although in justice to myself 1 must state, that when I first contrived the above-described instrument I was not aware of a similar prin- ciple having been adopted for this purpose. In the last num- ber of Prof. Silliman's Journal is a paper by Dr. Page de- scribing several pieces of apparatus to be used with Dr. Henry's gigantic coils ; one of these contrivances, ill-described however, consists of a bar of iron covered with a helix oscil- lating between the poles of a single permanent magnet, con- stituting, from my own experience, a very ineffective arrange- ment. To Dr. Page, however, must in justice be accorded the originality of the application of permanent magnets for the purpose of breaking contact. I remain, my dear Sir, yours truly, 22, Wilmington Square, Nov. 2, 1837- GoLDING BiRD. To Richard Phillips, Esq., F.R.S. L. ^ E., Sfc. N.B. The contact-breaker described in this letter was con- structed for me by Mr. Neeves, of Great St. Andrew's Street, Holborn. V. On a singular Development of Polarizing Structure in the Crystalline Lens after Death ; and. on the Cause, the Pre- vention, and iheCure of Cataract. By Sir David Brewster, K,G,H,, V.PKS.Ed.* TN examining the changes which are produced by age in -■- the polarizing structure of the crystalline lenses of animals, I was induced to compare these changes with those which I • From the Report of the Sixth Meeting of the British Association : Transactions of the Sections, pp. 16, 1 1 1 . Sec Lend, and Edinb. Phil. Mag., vol. viii. pp. 193, 416. Polarization in the Crystalline Lens after DeatJi, 23 conceived nii^ht takie place, after d^ath, when the lens was allowed to indurate in the air, or was preserved in a fluid me- dium. After many fruitless experiments I found that distilled water was the only fluid which did not affect the transparency of the capsule, and my observations were therefore made with lenses immersed in that fluid. The general polarizing struc- ture of the crystalline in the sheep, horse, and cow, consists of three rings, each composed o^ four sectors of polarized light, thjs two innermost rings being positive like zircon, and the outermost negative, like calcareous spar. In other cases, especially when the lenses were taken from older animals,ybMr rings were seen, the innermost of which was positive as before, and the rest negative and positive in succession. I now placed a lens which gave three rings, in a glass trough containing distilled water, and I observed the changes which it experienced from day to day. These changes were such as I had not anticipated; but though I have observed and de- lineated them under various modifications, I shall confine myself at present to the statement of the general result. There is a black ring between the two positive structures or lu- minous rings. After some hours' immersion in distilled water, this black ring becomes brownish, and on the second day after the death of the animal, a. faint blue ring of the first order makes its appearance in the middle of it, and its double re- fraction, as exhibited by its polarized tint, increases from day to day, till the tint reaches the white of the first order. Si- multaneously with this change of colour, the breadth of this new ring gradually increases, encroaching slightly upon the inner positive ring, but considerably upon the second positive ring; so that the black or neutral ring which separates the two positive structures, and in the middle of which a new lu- minous ring is created, divides itself into two black neutral rings, the one advancing outwards, and diminishing the breadth as well as the intensity of the second series of positive sectors, and the other advancing inwards, and diminishing the breadth and intensity of the inner or central sectors. While these changes are going on, the outer luminous or negative ring ad- vances inwards, encroaching also on the seco7id positive ring. Upon examining the character of the new luminous ring, the development of which has produced all these changes, I found it to be negative, so that at a certain stage of these va- riations we have a positive and a negative doubly refracting structure succeeding each other alternately, from the centre to the circumference of the lens, such as I have often observed in lenses taken from animals of greater age, and examined immediately after death. ^4 Sir D. Brevvstei' 07i the Cause, the Preventw??, After this stage of perfect development, when there is a marked symmetry both in the relative size and polarizing in- tensities of the four series of sectors, the lens begins to break up. The new negative ring encroaches so much on the two positive ones, which it separates, that the outer one is some- times completely extinguished, while the breadth and tint of the inner sectors are greatly diminished, so that the highest double refraction exists in the newly developed ring. In a day or two this ring also experiences a great change of di- stinctness and intensity, and the lens commonly bursts on the fifth or sixth day, sometimes in the direction of the septa or lines where its fibres have their origin and termination, and sometimes in other directions. In order to give a general idea of the cause of these singu- lar changes, I may state that the capsule which incloses the lens is a highly elastic membrane — that it absorbs distilled water abundantly — and that, in consequence of this property, the lens gradually increases in bulk, and becomes more glo- bular, till the capsule bursts with the expansive force of the overgrown lens. That the reaction of the elastic capsule contributes to modify the polarizing structure of the interior mass, cannot admit of a doubt, as it is easy to prove that that structure is altered by mechanical pressure; but I cannot conceive how such a reaction could create a new negative structure between two positive ones, and produce the other phaenomena which I have described. I have been led there- fore to the opinion, that there is in the crystalline lens the germ of the perfect structure, or rather the capability of its being developed by the absorption of the aqueous humour ; that this perfect structure is not produced till the animal frame is completely formed ; and that when it begins to decay the lens changes its density and its focal length, and some- times degenerates into that state which is characterized by hard and soft cataract. The results, of which I have now given an exceedingly brief notice, appear to me to afford a satisfactory explanation of those changes in the lens which terminate in cataract, a dis- ease which seems to be more prevalent than in former times. Accidental circumstances have led me to study the progress of this disease in one peculiar case, in which it was arrested and cured; and I am sanguine in the hope that a rational method of preventing, and even of stopping the progress of this alarming disease, before the laminae of the lens have been greatly separated or decomposed, may be deduced from the preceding observations. As the experiments, however, and views upon which this and the Cure of QUaract. 25 expectation is founded, are more of a physiological than of a physical nature, I am desirous of submitting an account of them to the Medical Section, that they may undergo that strict examination which they could receive only from the experience and science of that distinguished body. On the Cause, the Prevention, and the Cure of Cataract, Having submitted to the Physical Section an account of a singular change of structure produced by the action of distilled water upon the crystalline lens after death. Sir D. Brewster was desirous of communicating to the Medical Section some views which this, and previous observations, have led him to entertain respecting the cause and the prevention and cure of cataract. " The change of structure to which I have referred consists in the development of a negative polarizing band or ring be- tween the two positive rings nearest the centre of the lens ; the gradual encroachment of this new structure upon the original polarizing structure of the lens ; and the final burst- ing of the lens after it had swelled to almost a globular form by the absorption of distilled water. " As the crystalline lens floats in its capsule there can be no doubt that it is nourished by the absorption of the water and albumen of the aqueous humour, and that its healthy condition must depend on the relative proportion of these in- gredients. When the water is in excess the lens will grow soft, and may even burst by its over absorption ; and when the supply of water is too scanty, the lens will, as it were, dry and indurate, the fibres and laminae formerly in optical contact will separate, and the light being reflected at their surfaces, the lens will necessarily exhibit that white opacity which constitutes the common cataract. o " This defect in the healthy secretion of the aqueous hu- mour, as well as the disposition of the lens to soften or to in- durate by the excess or defect of water, may occur at any period of life, and may arise from the general state of health of the patient; but it is most likely to occur between the ages of 40 and 60, when the lens is known to experience that change in its condition which requires the use of spectacles. At this period the eye requires to be carefully watched, and to be used with great caution ; and if any symptoms appear of a separation of the fibres or laminae, those means should be adopted which, by improving the general health, are most likely to restore the aqueous humour to its usual state. Nothing is more easy than to determine at any time the sound state of the crystalline lens ; and by the examination of a small Phil Mag, S. 3. Vol. 12. No. 71. Jan. 1838. E 26 Sir D. Brewster on the Cause of Cataract, luminous image placed at a distance, and the interposition of minute apertures and minute opake bodies of a spherical form, it is easy to ascertain the exact point of the crystalline where the fibres and laminae have begun to separate, and to observe from day to day whether the disease is gaining ground or disappearing. " In so far as I know, cataract in its early stages, when it may be stopped or cured, has never been studied by medical men ; and even when it is discovered, and exhibits itself in white opacity, the oculist does not attempt lo reunite the se- parating fibres, but waits with patience till the lens is ready to be couched or extracted. " Considering cataract, therefore, as a disease which arises from the unhealthy secretion of the aqueous humour, I have no hesitation in saying that it may be resisted in its early stages, and in proof of this I may adduce the case of my own eye, in which the disease had made considerable progress. One evening I happened to fix my eye on a very bright light, and was surprised to see round the flame a series of brightly coloured prismatic images, arranged symmetrically and in re- ference to the septa to which the fibres of the lens are related. This phaenomenon alarmed me greatly, as I had observed the very same images in looking through the lenses of animals partially indurated, and in which the fibres had begun to se- parate. These images became more distinct from day to day, and lines of white light of an irregular triangular form after- wards made their appearance. By stopping out the bad parts of the lens by interposing a small opake body sufficient to prevent the light from falling upon it, the vision became per- fect, and by placing an aperture of the same size in the same position, so as to make the light fall only on the diseased part of the lens, the vision entirely failed. " Being now quite aware of the nature and locality of the disease though no opacity had taken place so as to appear ex- ternally, I paid the greatest attention to diet and regimen, and abstained from reading at night, and all exposure of the eyes to fatigue or strong lights. These precautions did not at first produce any decided change in the optical appearances occasioned by the disease; but in about eight months from its commencement I saw the coloured images and the luminous streaks disappear in a moment, indicating in the most unequi- vocal manner that the vacant space between the fibres or laminae had been filled up with a fluid substance transmitted through the capsule from the aqueous humour. These changes took place at that period of life when the eye undergoes that change of condition which requires the use of glasses, and Mr. R. Hunt 071 Triiiodtde of Mercuri/. 27 I have no doubt that the incipient separation of the laminss would have terminated in confirmed cataract had it not been observed in time, and its progress arrested by the means al- ready mentioned. Since that time the eye, though exposed to the hardest work, has preserved its strength, and is now as serviceable as it had ever been. *'If the cataract had made greater progress, and resisted the simple treatment which was employed, I should not have hesitated to puncture the cornea, in the expectation of chan- ging the condition of the aqueous humour by its evacuation, or even of injecting distilled water or an albuminous solution into the aqueous cavity." VI. On Tritiodide of Mercury. By Mr. Robert Hunt*. ¥ AM not aware that any one has observed more than two combinations of iodine and mercury, the yellow iodide and the scarlet biniodide; therefore a short account of a third may not be uninteresting. If with a saturated solution of the iodide of potassium we unite as much iodine as it will dissolve, and then add a sufficient quantity of the bichloride of mercury to separate the iodine of the salt, instead of the scarlet biniode, a purple-brown powder will be precipitated, which will be found to be one proportional of mercury combined with three proportionals of iodine, or Iodine 72-11 . ,^^ Mercury.. ^^.^ | m 100 parts. Three equivalents of iodine being 126x3 = 378 One equivalent of mercury 202 580 is its equivalent number. The tritiodide of mercury is soon resolved by exposure to the air into the biniodide, as it is also by alcohol, which se- parates one proportional of iodine. Heat likewise drives off a portion of the iodine, and the binary compound results. But if it is exposed in a strong glass tube filled with carbonic acid or the vapour of aether, and hermetically sealed, to the heat of a spirit flame, it sublimes in deep amber- colon red aci- cular crystals, which are tolerably permanent in the air. It is soluble in hot chloride of sodium, from which on cool- ing black fibrous crystals form, which I suspect to be a compound of chloriodic acid and soda ; but I have not yet had an opportunity of properly examining this compound. * Communicated by the Author. E2 2ff Mr. Walgon*s Mode of exhibiting the Colours of thin Plates. I find the addition of a little hydrochloric acid to the solu- tion of the bichloride of mercury renders the precipitated triliodide of mercury more permanent in the air. Robert Hunt. " ■ ' ' ' ■ ~~ " " " ' =^-^ VII. A simple Mode of exhibiting the Colours of thin Plates. By Mr, James Walgon. To the Editors of the Philosophical Magazine and Journal, Gentlemen, ALTHOUGH Newton's rings have often been described, I believe they have been but rarely seen. The reason is, because few persons have lenses, clamps, and screws suit- able for Newton's experiment. In your Journal for the month of March in the present year, (L. & E. Phil. Mag., vol. X. p. 183,) there is an article by the late Dr. Ritchie, en- titled, " A simple mode of exhibiting Newton's rings." Two circular pieces of thin plate glass, separated at the circumfe- rence by a single gold-leaf, are to be used instead of lenses ; but in order to bring the glass plates to touch in the centre, we must have " a rectangular frame of iron or brass, and a screw." I am afraid, therefore, that Newton's rings, as an ex- periment for illustrating the colours of thin plates, are not likely to be often visible, except in diagrams. I shall now proceed to describe a very simple mode of ex- hibiting the colours of thin plates by means of an experiment which requires no expensive apparatus. We have all seen the brilliant colours which are reflected from the narrow cracks in mica, and there are little concen- tric coloured rings in this mineral, which may be found by using a magnifier. It occurred to me lately that possibly these splendid colours might be made to appear in the mineral whenever required. To effect this I obtained a thin plate or film of air, by introducing a lancet into the edge of a clear plate of mica, carefully separating the laminae to the extent of about one inch square. Then holding the plate of mica with both hands, and pressing the middle finger of the right hand just under the spot where the film of air was made, I was much gratified by the appearance of several beautiful curved lines or bands of different colours, which followed the direction in which I moved my finger. These curved lines or bands in their forms very much resemble those of a fortification agate. The perfect rings are small, but they expand or contract ac- cording to the degree of pressure. The colours also change with the pressure of the finger, and when the finger is al- M. Simon oti Jervine^ a neiio Vegetahle Base. 29 together withdrawn, these beautiful tints all vanish in a mo- ment. We have then in this easy experiment a palpable proof that it is the distance between the surfaces only which determines the colours of thin plates. The plate of mica which we employ should be about the size of a page in an octavo book*, and about the thickness of a card. This size is convenient to hold with both hands, and the circumference of such a plate of mica will admit of several distinct plates of air. Films should be made between differ- ent laminae of the mineral, by which means we shall possess films of air, covered with plates of mica of different degrees of thickness. The colours may be seen very well with the naked eye, but they appear more beautiful when examined with a mag- nifier. The plate of mica should be held near a window, so as to reflect the light. Looking over your Number for October, p. 375, I saw Dr. Readers paper " on a permanent soap-bubble." I soon made this beautiful experiment, and beheld the splendid colours as described. In Dr. Readers permanent soap-bubble we have a liquid film, and in my experiment a film of air. I am, Gentlemen, yours, &c., London, Nov. 1, 1837. James Walgon. VIII. Jerviney a new Vegetable Base, By Edward Simon of Berlinf, I HAVE been so fortunate as to discover in the roots of the Veratrum album (Radices Hellebori albi), along with ve- ratria, a new vegetable base possessing some very remarkable properties. The alkaline extract from the root is boiled several times with water, which has been acidulated with muriatic acid, and the clarified acid liquid precipitated by a solution of pure carbonate of soda. It is necessary that the carbonate of soda be free from any mixture of sulphate of soda. The precipi- tate is dissolved in alcohol : the solution is then decolorated by means of carbon, and is separated almost, but not completely, from the alcohol by distillation. The residuum consolidates on cooling into a crystalline mass. This is then subjected to pressure, by which it is freed from the greatest part of the uncrystallizable veratria. If the pressed cake be once more moistened with alcohol and pressed, we obtain the new base tolerably pure. * Such plates of mica may be had of Knights, Fos^tcr Lane. "t From PoggcndoifTs Annalen, vol. xlix. p. 569. so M. Simon 07i Jervine, a new Vegetable Base, The expressed liquid contains both bases, namely, the new one and veratria. In order to separate the one from the other, the liquid was evaporated to dryness, and the residuum ' boiled with diluted sulphuric acid. The new base forms with sulphuric acid a salt of very difficult solution, which on cooling is precipitated, while the sulphate of veratria remains dis- solved. The treatment with sulphuric acid is again repeated with the residuum. This combination of the new base with sulphuric acid, so difficult of solution, is decomposed by boiling it with a solution of the carbonate of soda. The most suitable name for the new base would perhaps be veratria, if we might give to what has hitherto been called veratria the name of sabadilline, from its occurring in the seeds of sabadilla, which contain none of the new base. But the name veratria is so generally received for the base from saba- dilla seed, that it would be wrong to change it. We could not well term the new base helleborine, since by this means the confusion which already prevails between hellebore and Ve~ ra/rum might be further increased, and it is also possible that a peculiar base may be discovered in some species of helle- bore. I have given to the new substance the name of Jervine, because Caspar Bauhin, in his Pinax Theatri Botanici, p. 186, states, that the Spaniards call the poison from the Hellehorus albus de Balastera, or de Jerva, Jervine has some very peculiar properties. The most re- markable is, that it forms combinations with sulphuric acid, nitric acid, and muriatic acid, which are not very easily dis- solved in water. Of these the combination with sulphuric acid is the most difficult of solution. By an excess of acids these salts do not become much more soluble. If, however, the combination with sulphuric acid be boiled with much water, it is dissolved ; on cooling it again separates itself. The acetic and phosphoric acids form with this base combinations easily soluble in water. The base is precipitated from these solu- tions by the addition of the three above-mentioned mineral acids. By alcohol, the salts of the base which are difficult of solution, are rendered soluble ; the solubility, however, in alcohol is not so great as in the salts of the other organic bases. It has previously been mentioned, that the combina- tions of the base which are hard to be dissolved, for instance those with sulphuric acid, are decomposed by boiling them with alkaline carbonates. [M- Simon is evidently unacquainted with the sabadilline described by M. Couerbe, in Ann. de Chim. el dc Phys., vol. lii., p. t37fi ; a substance closely allied to that v hich he has noticed, if not identical with it — Edit.] 31 IX. On a Method of Anali/sifig Organic Compounds. By Robert Rigg, Esq,, M,RJ,* To Richard Phillips, Esq., RR.S. Dear Sir, tJAVING been so frequently solicited by those who have ■*• ^ seen me analyse organic compounds to make an early and more public communication than I have yet donet of the method which I adopt, I beg the favour of your inserting in the Philosophical Magazine the following brief account of my very simple apparatus, premising that if at any period I should publish my researches altogether, I shall then go into detail upon this department of chemical manipulation. The analytical apparatus consists of two small glass tubes connected by a caoutchouc collar, as shown below. C_3= l_Ji A. A tube, in which is placed the organic compound to be analysed, and which for the analysis of one grain is from seven to ten inches in length, and from three to four tenths of a cubic inch in content. B. A caoutchouc collar, about an inch in length, in which is put a little dry amianthus or cotton wool. C. A bent thermometer tube for conveying the gaseous pro- ducts to the receivers standing over mercury. The compound to be analysed, a portion of it having been burnt in a platinum spoon with a view to determine the quan- tity of residual mailer, is mixed in the usual way with black' oxide of copper X, varying in quantity from thirty to fifty grains for each cubic inch of carbonic acid gas that will be formed, and varying also with the quantity of water that will be formed. This mixture is put into the clean and dry tube, and upon it * See p. 422 of our last volume. — Edit. •f A diagram and description of the apparatus was laid before the Royal Society about two years ago ; and the apparatus itself, together with a tube for measuring minute quantities of nitrogen, before the Chemical Section of the British Association in September last. I The black oxide, which 1 prepare by burning copper turnings, and not from nitrate of coppery is exposed to a white heat for an hour at least, and well stirred. I afterwards spread it on a plate, where it lies from ten to twelve hours; put it into a bottle, shake it well, and then accurately de- termine the quantity of air and moisture it has condensed ; these remain stationary, when it is kept in stoppered bottles, during the use of two or three pounds of oxide so prepared. [See Dr. Prout*s observations on this subject in Phil. Mag. and Annals, vol. iii. p. 35. Edit.] 32 Mr. Rij^g on a Method of analysing Organic Compounds, an inch or more of the same kind of oxide : the tube is then filled up with from fifteen to twenty-five grains of dry amian- thus, and which, during the process of decomposition, con- denses tlie vapour of water, and dries the gaseous products. The part of the tu])e which includes the amianthus is then heated, so as to drive off all moisture and decomposable mat- ter that may be combined with it, and allowed to cool, when it is weighed, and attached lo the bent tube by the collar, as shown in the diagram. The bent tube is placed in the mer- curial trough, and the analysing tube rests on the frame or cradle, made of two pieces of strong wire bent at both ends at right angles, and connected together in an oblique direction by slender wires, as represented in the subjoined diagram. A spirit lamp upon the principle invented by Mr. Cooper, and which can at pleasure be made to give off a flame from one to six, or from one to ten inches in length, and about six inches in height, is what I use. A flame, about an inch in length, is first applied to that part of the tube where no organic com- pound lies ; so soon as this part of the oxide is brought to a red heat, the flame is gradually but very slowly increased in length, until all that part of the tube, where the compound and black oxide are, is at a white heat. During this period the tube is turned round in the flame, the caoutchouc collar ad- mitting of this being done at pleasure. At no time is the de- composition of the substance under analysis quick, but, on the contrary, very slow. The ignited part of the tube being kept at a high temperature, we insure perfect combustion, and pre- vent the formation of carbonic oxide, which is in all proba- bility the source of much error in quick processes. During the latter part of the process, and when it is certain that all the atmospheric air has been expelled, a portion of the gaseous products is collected in a separate small tube gra- duated to hundredths of a cubic inch. When no more gas passes over, the flame is extinguished, and the contents of the tube are shifted by raising and lowering it with a view to that end, and without removing the bent tube from the mercurial trough. The whole being arranged again as at the commence- ment, that part of the tube which contained the compound under analysis is submitted to a higher temperature, if pos- sible, than before. The analysing tube is now detached from the other, al- lowed to cool, and weighed, and the weight lost is found to be / . Mr. Rigg 071 a Method of analysing Organic Compounds, 33 that of tiie gaseous products which have passed from it, all the water having been absorbed by the amianthus. The bent tube is at this time filled with the gaseous pro- ducts of the analysis, and when the analysing tube is cooled, about -,3- of its interstices are also filled with the same, and this I take into account in calculating the products. On heating the analysing tube again, driving off all the moisture, allowing it to cool, and then weighing it, I have the total loss in weight to the yo^o ^* ^ g''^i"» ^^^ the contents of the tube in a dry state. I remove the carbonic acid gas by liquid potassa, and the residual gas, which is left in the small tube which is filled during the latter part of the process, is first transferred into the upper part of the graduated tube represented in the margin *, and where its volume can be read to t-oW of a cubic inch. This I calculate for as nitrogen. The other residual gas is then transferred into the same tube, and the volume of the two read in the centre part to the 2^0 of ^ cubic inch. If no nitrogen is present in the compound under examination, the volume of the residual gas is less than that of the atmospheric air in the oxide, together with that which had filled the interstices of the analysing tube, the caoutchouc col- lar, and the bent tube, and contains less oxygen. The nitrogen obtained from the gaseous products which are collected in the small tube, serves as a term of comparison for verifying the results of the experiments which I make expressly for the purpose of determining the quantity of that element; and where its existence is doubtful, as, for instance, in sugar, starch, &c., I first fill the tube with carbonic acid gas, use black oxide of copper which has not been exposed to the air, apply the ^oxne^first to the end of the analysing tube, and am especially careful that no carbonic oxide is formed. The weight of water, and also that of carbonic acid gas and nitrogen, together with their volumes, being known, this mode of conducting ultimate analysis enables me to determine ac- curately the quantity of water by weight, and the quantity of carbon and nitrogen, both by weight and by volume, in any given compound. And, further, I have the data for a very ac- curate recapitulation of all the products, so as to be able to speak with tolerable certainty as to the correctness or incor- rectness of any experiment so made, and also for testing the correctness of data already received as regards the weight and volume of the different [elements contained in the com- pound under analysis. The experiments that I have made with this simple ap- * Several tubes of this kind are required in order to measure the quanti- ties of nitrogen contained in different compounds. Phil Mag. S. 3. Vol. 12. No. 71. Jan. 1838. F 34 Dr. Falconer q?td Capt. Cautley on additional paratus are very numerous. I have before me at this time more than five hundred substances, which I have analysed with a view to discover the chemical changes which occur during the preparation of the earth for thegrowth of vegetables, the germination of seeds, the vegetation of plants, the for- mation of vegetable products, the renovation of the atmo- sphere as regards both nitrogen and oxygen, and the various decompositions of vegetable matter; and many additional experiments will be required to complete the course of analysis which I find to be necessary to the purposes I have in view. The whole inquiry has reference more particularly to agricul- ture, to horticulture, and to some of those manufactures in which vegetable products are employed. Robert Rigg. Walworth Road, Dec. 6, 1837. X. On additional Fossil Species of the Order Quadrumana from the Sewalik Hills, By H. Falconek, Esq.^ M»D., and Captain P. T. Cautley.* [With Figures : Plates I. and II.] 1 N the November number of the Journal, (of the Asiat. Soc. of -■■ Bengal,) vol. v. p. 739, Messrs. Baker and Durand have an- nounced, in the discovery of a quadrumanous animal, one of the most interesting results that has followed on the researches into the fossil remains of the Sewalik Hills. The specimen which they have figured and described comprises the right half of the upper jaw, with the series of molars complete; and they infer that it belonged to a very large speciesf . In the course of last rains we detected in our collection an astragalus, which we referred to a quadrumanous animal. The specimen is an en- tire bone, free from any matrix, and in a fine state of presei*- vation from having been partly mineralized with hydrate of iron. It corresponds exactly in size with the astragalus of the Senmopithecus Entellus or Langoor, and the details of form are so much alike in both, that measurement by the callipers was required to ascertain the points of difference. We have forwarded the specimen with a notice to the Geological So- ciety of London, after keeping it some months in reserve, having been diffident about resting the first announcement of fossil Quadrumana on any thing less decisive than the cranium or teeth J. This astragalus, in conjunction with Messrs. Baker and Durand's specimen, satisfied us of the existence of at least two distinct fossil Quadruma?ia in the Sewalik Hills. We have lately become possessed of several fragments, more or • From the Journal of the Asiatic Society of Bengal, vol. vi. p. 354. t For Lieuts. Baker and Durand's paper, see Phil. Mag., vol. xi. p. 33. J See our report of the proceedings of the Geological Society, p. 393 of our liuit Yolume,<— '£pix. Xoruixnv^JEdinlf. FML. ^^tCa^- Vol :XIT. TUl. Foj^iL. Fi^.jil- jFoJsiZ. Fi^. S. ^cale, ^ e?fjyiri. siXA. f"^lpl/^C£uMe}r, ori^. JYinted^ iy J. Sasire^. Fossil Species of Quadrumana from the Sewalik liills. S5 less perfect, belonging to the lower jaws of two species, both smaller than Messrs. Baker and Durand's fossil. These we shall now proceed to notice. The principal specimen is represented in fig. 1 . [PI. I.] It consists of both sides of the lower jaw ; a great portion of the right half is entire, with the whole series of molars ; the left half is broken off to the rear of the antepenultimate molar. The two middle incisors are present, and also the left canine broken across at its upper third. The right canine and the lateral incisors had dropt out, leaving but the alveoli. The molars of the left side are destroyed down to the level of the jaw. The right ramus is wanting in more than half its width, together with the articulating and coronoid processes, and a portion of the margin at the angle of the jaw is gone. The specimen is a black fossil, and strongly ferruginous ; the spe- cific gravity about 2*70. It was incased in a matrix of hard sandstone, part of which is still left adhering to it. The jaw had belonged to an extremely old animal. The last molar is worn down so as to have lost every trace of its points, and the three teeth in advance of it have been reduced to hollo wed-out discs, encircled by the external plate of ena- mel. The muscular hollow on the ramus for the insertion of the temporal muscle is very marked, being *S5 inches deep upon a width of '55, The dimensions contrasted with those of the Langoor or Semnopithecus Entellus and the common Indian monkey, or Pithecus Rhesus, are as follow : — Dimensions of the Lower Jaw. ■5 S 11 2 w 3 3 to Z. 1. Extreme length from the anterior"! margin of the ramus to the mid- \ die incisors J 2. Extreme length of jaw (calculated ) in the fossil) j 3. Height of jaw, under the second 1 molar measured to the margin of V the alveoli J 4. Ditto at the rear molars 5. Depth of symphysis 6. Space occupied by the molars 7. Interval between the first molars . . 8. Antero-posterior diameter of thel canine / 9. Width of jaw behind the chin un- 1 der the second molar J inches. 3-6 5-3 1-35 1-2 1-9 2-3 •9 •5 115 inches. 2-85 105 11 1-4 1-9 •75 •4 1-05 inches. 2-5 3-6 •85 •95 M 1-5 •65 •3 •95 3-2 3-02 4 31 3-6 3- 4 33 4 3-2 4 3-2 4 3^7 30 Dr. Falconer arid Capt. Cautley on additioiial As in all other tribes of animals in which the species are very numerous, and closely allied in organization, it is next to impossible to distinguish an individual species in the Qua- drumana from a solitary bone. In the fossil, too, the effects of age have worn off those marks in the teeth by which an ap- proximation to the subgenus might be made. It very closely resembles the Semnopithecus Entellus in form, and compara- tive dimensions generally. The differences observable are slight. The symphysis is proportionally a little deeper than in EntelluSi and the height of the body of the jaw somewhat greater. The chin, however, is considerably more compressed laterally under the second molar than in the Entellus, and the first molar more elongated and salient. So much of the canine as remains has exactly the same form as in the Entel- Itis, and its proportional size is fully as great. As shown by the dimensions, the jaw is much larger than in the full-grown Entellus: in the former the length would have been about 5*3 inches, while in the latter it is exactly 4 inches. The fossil was a species of smaller size than the animal to which the specimen described by Messrs. Baker and Durand be- longed, but less so than it exceeds the Entellus. Our limited means for comparison, restricted to two living species, besides the imperfection of the fossil, and the few characters which it supplies, do not admit of affirming whether it belongs to an existing or extinct species ; but the analogy of the ascertained number of extinct species among the Sewa- lik fossil mammalia, makes it more probable that this monkey is an extinct one than otherwise. There is no doubt about its differing specifically from the two Indian species with which we have compared it. The next specimen is shown in fig. 5. [PI. I.] It is a fragment of the body of the right side of the lower jaw, containing the four rear molars. The teeth are beautifully perfect. It had belonged to an adult, although not an aged animal, the last molar having the points a little worn, while the anterior teeth are considerably so. The dimensions, taken along with age, at once prove that it belonged to a different and smaller spe- cies than the fossil first noticed. The dimensions are as follow : — Dimensions of the Lower Jaw. Smaller fos- sil Sewdlik species. Larger fossil Sewalik spe- cies. Semno- pithecus Entellus. Pithecus Rhesus. 1. Length of space occu- pied by the four rear molars J 2. Height of jaw at the > third molar / inches. 1-48 •95 inches. 1-7 inches. 1-48 M 1-25 •9 Fossil Species of Qjiadrwnanafrom the Se*mdlik Hills. S7 The length of jaw, therefore, estimated from the space oc- cupied by the teeth, would be 4 inches, while in the larger fossil it is 5*3 inches, a difference much too great to be de- pendent merely on varieties of one species. Besides, we have another fragment, also belonging to the right side of the lower jaw, and containing the last molar, which agrees exactly in size with the corresponding tooth in the figured specimen*. This goes to prove the size to have been constant. The fos- sil, although corresponding precisely in the space occupied by the four rear molars with the Entellus, has less height of jaw. There is further a difference in the teeth. In the En-- tellus the heel of the rear molar is a simple flattened oblique- surfaced tubercle, rather sharp at the inside. In the fossil, the heel in both fragments is bifid at the inside. The same structure is observable in the heel of the rear molar of the common Indian monkey P, rhesus. It is therefore probable that the fossil was a Pithecus also. It was considerably larger, however, than the common monkey, and the jaw is more flat- ■ tened, deeper, and its lower edge much sharper than in the latter. This difference in size and form indicates the species to have been different. It would appear, therefore, that there are three known spe- cies of fossil Quadrumana from the Sewalik Hills : the first a very large species, discovered by Messrs. Baker and Durand ; the second, a large species also, but smaller than the first, and considerably larger than the Entellus; the third, of the size of the E?itellus, and probably a Pithecus; and further, that two of the three at least, and most probably the third also, belonged to the types of the existing monkeys of the old Con- tinent, in having but five molars, and not to the Sapajous of America. There are at present upwards of 150 described species of existing Qiiadrumana, and as the three fossil ones all belonged to the larger-sized monkeys, it is probable that there are several more Sewalik species to be discovered. We have some specimens of detached teeth, of large size, which we conjecture to be quadrumanous ; but their detached state makes this conjecture extremely doubtful. Besides the interest attaching to the first discovery in the fossil state of animals so nearly approaching man in their or- ganization, as the Quadrumafia, the fact is more especially in- teresting in the Sewalik species, from the fossils with which they are associated. The same beds, or different beds of the same formation, from which the Quadrumana came, have yielded species of the camel and antelope, and the Anoplo^ [* We presume that fig. 4. of PI. I. represents this third fragment.— Edit.] 38 Dr. Falconer atid Capt. Cautley on additional therium posterogenium^ (nob.): the first two belonging to genera which are now coexistent with man, and the last to a genus characteristic of the oldest tertiary beds in Europe. The facts yielded by the reptilian orders are still more in- teresting. Two of the fossil crocodiles of the Sewaliks are identical, without even ranging into varieties, with the Croco- dilus hiporcatus and Leptorynchus Gangeticus, which now in- habit in countless numbers the rivers of India; while the Testudinata are represented by the Megalochdys Sivalensis (nob.), a tortoise of enormous dimensions, which holds in its order the same rank that the Iguanodon and Megalosaiir^us do among the Saurians, This huge reptile (the Megalochdys) — certainly the most remarkable of all the animals which the Sewaliks have yielded — from its size carries the imagination back to the «era of gigantic Saurians. We have leg bones derived from it, with corresponding fragments of the shell, larger than the bones in the Indian unicorned rhinoceros ! There is, therefore, in the Sewalik fossils a mixture in the same formation of the types of all ages, from the existing up to that of the chalk ; and all coexistent with Qimdrumana. P.S. Since the above remarks were put together, we have been led to analyse the character presented by a specimen in our collection, which we had conjectured to be quadrumanous. The examination proves it to be so incontestably. The speci- men is represented in figs. A, B, and C [of PI. II.] It is the extra-alveolar portion of the left canine of the upper jaw of a very large species. The identification rests upon two vertical facets of wear, one on the anterior surface, the other on the inner and posterior side, and the proof is this. The anterior facet b has been caused by the habitual abrasion of the upper canine against the rear surface of the lower one, which overlaps it, when the jaws are closed or in action. This facet would prove nothing by itself, as it is common to all aged animals in the carnivora and other tribes in which the upper and lower canines have their surfaces in contact. The second facet c must have been caused by the wear of the inner and rear surface of the canine against the outer surface of the first molar of the lower jaw. But to admit of such contact, this molar must have been contiguous with the lower canine, without any blank space intervening ; for if there was not this contiguity, the upper canine could not touch the lower first molar, and consequently not wear against it. Now this continuity of the series of molars and canines without a diasteme or blank interval, is only found, throughout the whole animal kingdom*, in man, the Qtiadrumana^ and the * Ciivier, Ossemcns Fossiics, tome iii. p. 15. Fossil Species of Qiiadrumanafrom the Sewdlik Hills. 39 Anoplotherium, The fossil canine must therefore have be- longed to one of these. It were needless to point out its dif- ference from the human canine, which does not rise above the level of the molars. In all the species of JJnoplotherium described by Cuvier, the canines, while in a contiguous series with the molars, do not project higher than these, being ru- dimentary, as in man. Of the Sewalik species, Anoplothe- rium poste?'ogenium (nob.), we have not yet seen the canines ; but it is very improbable, and perhaps impossible, that the fossil could belong to it. For if this species had a salient canine, it must have been separated from the molars by an in- terval, as in the other Pachydermata ; otherwise the jaws would get locked by the canines and molars, and the lateral motion required by the structure of the teeth, and its herbi- vorous habit, would be impracticable ; and if there was this interval, the upper canine could not have the posterior facet of wear. The fossil canine must therefore have belonged to a quadrumanous animal. This inference is further borne out • by the detrition of the fossil exactly corresponding with that of the canines of old monkeys. The dimensions are: — Length of the fragment of canine . . 1*75 inches^ Antero-posterior diameter at the base . '8 Transverse ditto . ,. . . . •? Width of the anterior facet of wear . -6* The two diameters are greater than those of the canine of the Sumatra Orang-otang described by Dr. Clarke Abel* as having been 1\ feet high. The Cynocephali have large and stout canines, more so comparatively than the other QiiadrU" mana. But to what section of the tribe our fossil belonged, we have not a conjecture to offer. We may remark, how- ever, that the tooth is not channeled on three sides at the base, as in the Entellus. Does the fossil belong to the same species as the jaw discovered by Messrs. Baker and Durand, or to a larger one ? Note by the Editor of the Journal of the Asiatic Society, — We have sketched" Dr. Falconer's highly curious fos- sil tooth in position with the lower jaw of the Sumatran Orang-otang from the Society's Museum, in fig. C [of PI. II.] There is a third facet of wear at the lower extremity d, which on reference we find Dr. Falconer attributes, like c, to attrition against the first molar, being observable, he says, in many aged animals. The worn surfaces c and d are uni- formly polished, and have evidently originated from attrition against a tooth ; but with regard to the principal facet b, we * Asiatic Researches, vol. xv. p. 498 ; [or Phil. Mag. and Annals, N. S. vol. i. p. 219.] 40 Mr. Prinsep and Col. Colvin's Notice of confess we have a degree of scepticism, which can only be re- moved by a certainty, that the fossil had been seen extracted from the matrix. In the first place, the great extent of the worn surface and its perfect flatness could hardly be caused by attrition against the lower canine, which should produce a curvature measured by the length of the jaw as radius. In the next place, the enamel of the tooth is less worn than the interior and softer part of the fossil ; and, thirdly, on exami- nation with a magnifier, numerous scratches are visible in divers directions : all these indicating that the facet may have been produced o?i the fossil, by grinding it on a file, or some hard flat surface. On showing the fossil to Madhusudana, the me- dical pandit of the Hindu College, he at once pronounced that the tooth had been ground down to be used in medicine, being a sovereign specific in the native pharmacopoeia. This circumstance need not necessarily affect the question, for it is probable that the native druggist would commence his rub- bing on the natural plane, if any presented itself to his choice ; but Dr. Falconer and Captain Cautley, to whom we have re- turned the fossil with a communication of our doubts, assure us in reply that the fossil tooth was brought in along with a large collection, so that there is every improbability of its having been in possession of a native druggist. At any rate, it is not on the front wear that they so much rest their f.rgu- ment of its origin, as on the posterior abrasion, which could only happen in the jaw of a quadrumanous animal. In fact, they have recent quadrumana showing precisely similar wear on a small scale, and no other head will do so. We find only one exception in the Society's Museum, viz., the tapir, whose right upper incisor (or non-salient canine) falling be- tween the two lower ones, is worn nearly in the fashion of the fossil ; but it is less elongated. XI. 'Notice of additional Fragments of the Sivatherium,* [With Figures : Plate II.] BEFORE Colonel Colvin's departure for Europe, we re- quested permission to take a cast of the beautifully pre- served lower jaw of the Sivatherium which he exhibited at the Government House scientific party in January last [1837]. In further token of his zeal for science, and of his ever-readiness to oblige, he has, even in the hurry of embarkation, favoured us with the accompanying lithographic drawings of the same jaw, and of the larger fragment of the occiput, also on its way to adorn some cabinet of fossil osteology in his native • From the Journal of the Asiatic Society of Bengal, vol. vi. p. 152 j being a communication by the Secretary, James Prinsep, Esq., F.R.S. j:orulorv:EeiLn2> ThzZ. ^Moj^. voljni. TLIL Ttg. 3. 'is of ^CCUiToL^lXe. jy of*/ntiuraZ ^z^. CdL^0?lrito* C 42 ] XII. Meteorological Observations for Portions of the Years 1836 and 1837, made at Bermuda; and a Notice of an Aurora Bor calls seeti in low Latitudes, By Lieut, -Col. A. Emmett, Royal Engineers, To the Editors of the Philosophical Magazine and Journal, Gentlemen, nPHE great attention now given to meteorology induces me -*■ to forward for the Philosophical Magazine asummary of the observations taken by me within the period of twelve months*. Every attention has been given to their accuracy ; and from the character of the instrument-maker, Mr. Newman, I think they may be received with confidence. I am well aware that the observations of twelve months are insufficient for establish- ing'many data, yet there are two or three points which merit attention, particularly that of the horary changes. I shall not at present trespass further on your pages than to notice that a most splendid aurora borealis was seen here on the 25th of January, as also even down to the tropics, re- specting which I transcribe an extract from the journal of Captain Willis of H.M.S. Cruiser, which he was kind enough to send me from Jamaica : " In lat. 22° north, long. 57° west, at 8 p.m., the aurora borealis was observed very brightly ; it began at 8 by a red flush suddenly spreading itself over a great part of the northern hemisphere, extending in altitude to about S0« ; then a number of streamers showed themselves shooting upwards with great brilliancy. They continued about fifteen minutes, then ceased, leaving that part of the sky for a time blood red." The appearance here was very similar, but more extensive and of longer continuance. I remain, &c. Bermuda, Julv 1 1 , 1837. A. Emmett, Lieut.-Col., R. E. P.S. This aurora appears to have been seen over a large extent of North America. ♦ Lieut.-Col. Enmiett's observations for the period from July 1 to Sep- tember 30, 1836, having already appeared, in the paper prepared by Dr. Dalton, inserted in our last volume, p. 44.0, we have omitted them in the tables which follow; retaining, however, the means for the entire six months, from July 1 to December 31, 1836.— Edit. ^ :: 0< §«r .5 c ^ J= w a 00 00 f— t 1-3 to a ^'m ^i j -spuiAV 5? «3 G 0! '^ ^ o< --H o< c/^:?; •saiBO ^ ^ "•I^ ©t *&> J0 8UU01S ^^ 1— 1 CO S o CO ^ 05 •f^ ^ ^» CO g:^ ^ CO CO "^ 1 G^ c . 00 CO ©< o CO o •3 1, o io CO •♦«» « g "^ m CO to a 1 ;o !>► t* CO 's^ tJ »^ !>. o Oi t>« 2 a 2 ^ ■* c^^ Ol Q> > O "^ "T tp o § § = op jT £ «l Tf ■"T" ■^ ". E e9 kO o< •^ ^ .<" S ob CO o 1^ H t>« t^ t^ t->. "^i Q C i^ >o o OS to CO 1 CO to o • •««« t^ «o CO t>» "««» § ^ 00 o © to f* o Oi CX) ^ Q o t>. »>. s OS • • ►^ o "^ o o o • a :3 w CO ■^ CO «*»4 a t>. to 00 l->. ■1 a o s _i^_ § OS 0^ ©^ o ^ to z Ji 00 o< O) !>• Q 03 ©< CO CO CO <;j 1 ;i o o o o CO CO CO CO 00 o o O) c t^ en »o -rt* S 05 05 o S § -^- o CO o CO 1 > o ^ o /^ Q £*»*-' ca . W 0; C ^ u c < ,0 Q, • "^ fcC 43 c o 'cS '5 p.S ^•- S-rt R ^ '-' > ji. ^ «« c O . O 13 S O -^ en S (1> § cft 'O <« -Q • Ci) 52 feo = -^ ^ « ^ . — , O ^ ^ c cc .^ cc-S O « O w O ^ r- - ^ S « o ? ^ G-1 Cf °^ C a ^ C CO ti ca ^-^^ S . O *= G *G S !f G (y > to W) ^ ^^ ^^ M^,. si^ mw --^OiCO s •spuiM 2;^ '/5 C 5l r-1 Q^ CO c *3 •sapo |i o CO •^ E 0^ o E CO •^ Tf CO „. oo rt« wo CO CO CO ©» rrs ©* ^ ^ -^ CO o t^ 00 •^ CO OS CO CO H CO CO -^ CO CO 00 t^ ©i J^ o c ©< ©I ©I »o *; «o CO 00 (^ CO . CO CO t^ '5 •a 2 o CO CO s op ©< CO CO ©» CO « CO ^ CO 00 ^ 00 !>. Tt* CO 00 ©J CO ©> 00 rt a »o CO !>. o • CO ^ Q CO CO ^ t^ ■"^ 00 ^ s >4 ^ u. 5 CO ?> CO o» -"f Ol »o J(>^ lA a, ©< (^ CO «J0 t>» 00 OS 00 CO (U ff '^ ■^ TJ- lO CO ''T XTj ^ to "f^ £ ? > * * * ' • o CO bO ^c 05 ^ ©t t>. 00 !>. r>» 00 ^ X =£ 0^ Tt< CO CO _H t^ t>« ■^ t^ o lO »o lO lO CO CO xCi CO uo CO ^ •Bssjoajn^ ^ Tt* rfi ©* ©t CO ©« 00 t^-^ ^1 <^ E OS o 2 -Bjaduiax CO ;o coco coco coco CO !>. i l>« s ^ hi •O lO in CO OS CO CO Q o ,_ ,_, CO CO CO CO Tfl CO kO ^ o< G^^ '"' *"* ""^ '"' r-l ■s a uo >jO "5 CO CO «p »o 3 § t>. t>. CO lO 00 CO ■^ ©J ■^ 00 { a ""f "t "5 lO liO CO »o CO »o U3 ^ £ 1 00 ■4" f* iO OS ©t CO H to CO CO *>. t>. !>. !>. !>. t>. t>» S . 9 ^ 05 CO -'t -* § ^ 00 do CO OS 00 ©* OS ©? CO CO CO- CO ^ "5 »o CO CO !>. CO o. CO CO CO o CO ©> rp 00 ,_, lO ,^ CO iB 00 lO !>. CO ©^ CO CO »->. n op l>» op « "T ^ !>. CO 1^^ CO ©I "^ o* ■^ 00 CO o< -* o "* , , 05 CO ■^ OS CO CO -"^ CO Tt^ o i 1 CO !>. ■^ »c OS !>. CO l^ CO t~^ § Oi OS OS OS OS OS OS OS OS ©< c^^ ©i o» ©^ ©< ©« ©< ©< © o^ o o o o iC KO »o to gij • 00 00 o< CO lO OS t^ *^ t>. t^ < .9, i;^ ©< Tt< CO T^ CO CO CO CO CO CO CQ 3 o o o o o o o o o o CO CO CO CO CO CO CO 1 CO 1 CO CO o* •o OS OS OS § CO ©< CO t>. 1 • ;o CO OS 00 CO OS •^ cs ,_^ 1 t^ o OS OS OS o OS o OS o OS OS o ^ OS o OS o •^ 1 0< CO ©* 01 CO ©» CO 1 ©« CO s o 3 4 CI 2 1 J2 < 1 li •"* II 5 Meteorological Observations at Bermuda, 45 Comparison of Barometer at 9 a.m.^ ^ p.m., and 9 p.m. Month. 1836. No. of Observa- tions. 9 A.M. 4 P.M. Diff. No. of Observa- tions. 9 P.M. 4 P.M. higher than 9 a.m. July. 24 30-162 30149 •013 24 30-183 7 August. 23 30-138 30-108 •030 23 30^132 6 Sept. 18 30-140 30107 •033 18 30^1 32 2 October. 18 30066 30-034 •032 18 30053 1 Nov. 26 30062 30031 •031 ... ... 6 Dec. 30 30-224 30-188 -036 27 30-215 5 Mean. 139 30-132 30103 •029 110 30-145 27 1837. \ Jan. / 30 29-892 29-832 •060 24 29865 5 Feb. 27 30-132 30101 •031 14 30-118 7 March. 30 30075 30-032 •043 25 30-048 7 April. 23 30 027 30-007 •020 17 30052 5 May. 22 30136 30-128 •008 6 30104 5 June. 24 30075 30-054 •021 22 30071 5 156 30057 30-025 •032 108 30-043 34 1836 139 30-132 30103 -029 110 30-145 27 1837. 156 30-057 30025 -032 108 30043 34 61 Total 1 Mean. / 295 . 30094 30-064 -030 218 30094 All the observations at 9 a.m. and 4 p.m. were taken on the same days ; those at 9 p.m. not always so. No correc- tions are made. Occasionally, that is in the proportion of 1 to 5, the barometer is higher at 4 p.m. than at 9 a.m. Time at Bermuda is not correctly kept, but during the hot season the critical hours appear to be between 8 and 9, and about 4 ; at other times half an hour nearer noon. The horary difference exceeds in a very trifling degree that at Paris. Various Memoranda, Barometer used, Newman's iron cistern portable. 46 Mdeot'ological Observations at Bermuda, Thermometer, Newman's compared with one furnished as a standard, with his own. Dew-point. The difference between the attached thermo- meter and the moist bulb multiplied by ^, and subtracted from the latter, gives that point nearly; but less depend- ence is to be placed on these columns than on any other. Winds : relative Proportions, 1836. N. NE. E. SE. s. sw. w. NW. July. ... 1 19 9 44 10 10 August. 3 8 1 15 2 39 11 14 Sept. 4 24 8 24 11 10 3 6 Oct. 11 17 1 22 8 25 2 7 Nov. 4 12 4 18 3 10 2 32 Dec. 6 16 4 21 8 21 ... 21 28 77 19 119 41 149 28 90 1837. Jan. ... 3 2 27 10 47 1 3 Feb. 9 5 ... 7 8 22 4 29 March. 19 26 1 ... 4 16 1 24 April. 12 7 3 5 9 28 8 18 May. 4 23 9 19 12 9 8 8 June. 9 6 ... 18 8 24 6 19 53 70 13 56 44 126 37 145 1836. 28 77 19 119 41 149 28 90 81 147 32 169 85 275 65 235 The winds are taken at sun-rise, noon, and sun. set, and collected and classed therefrom. They are often very irregu- lar, and on many occasions have been at every point of the compass within twenty-four hours. They often freshen about 9 a.m., moderate after noon, and again freshen towards sun- set ; but these changes are not general. Calms of 24 or 36 hours occasionally occur in the months from June to September, but not often so long ; but they are frequent for shorter periods, mostly in the afternoon. Mr. Lubbock on the Wave-surface in Double Refract ion, 47 General Observations on the Year. Barometer, Greatest height, corrected and reduced, 30-664; least ditto, 29*414; greatest range, 1*25: highest with NE. and SE. winds; lowest, with NW. and SW. Thermometer. Greatest observed power of common black bulb, 106°; greatest observed heat of ground, thermo- meter barely covered, 142°; sun's greatest force about 1 p.m. ; hour of greatest heat 4 to 4^ in the hot season, and 3 to 3^ at other times. Dew-point, accords with the latter. Clear days, proportion 1 to 4 or 5. Halos, rare. A. Emmett, Lieut.-Col. Royal Engineers. XIII. On the Wave-siirface in the Theory of Double Refraction. By J. W. Lubbock, Esq.^ F.R,S.* ■jl/FR. TOVEY remarks, p. 524 of the last Number, that I "'-*-■- have taken for granted that the differential equations of molecular attraction may be reduced to the form I confess that the reasoning of Fresnel connected with this matter is to me by no means clear, but I presume the reduc- tion will at all events be admitted to be possible in the man- ner pointed out by M. Cauchy in the Nouveaux Exercises, p. 11, the axes of elasticity being the principal axes of the curve of the second order given by the equation (36.), p. 12. Instead of taking I might have taken, in the manner of Mr. Kelland and of M. Cauchy, q = Acos {nt-kr) -^|- = - F^. A^= —Aco^{nt — kr){\ -cos (A: A r)) +^sin (/z^— A:;)sin(A: A r) = — 2 sin^ ( ] ^-\- Asm (n t — k r) sin {k A r). Neglecting the .terms multiplied by sin (k Ar), for the rea- sons given by M. Cauchy, p. 10, if {^ sin^( ■ r + rj, (r) A ^« y y ^ A f = A § cos X A >j = A ^ cos Y A ^ = A g cos 21 ^ = I fl2 cos* X+ 6^ cos^ Y + c' cos^ ;2 i -^f = ^^ •x-# ^^ = «' cos2 X + b'cos^ Y+c cos- ^, ii q ■=. A cos («^— Z^r), this expression represents a wave of light, moving with a velocity v = -r-, the length of the wave In my paper in the last Number, p. 492, 1. 4f,Jbr " a function of those coefficients," read " a function of those constants." XIV. On the peculiar Voltaic Conditions of Iron and Bismuth, By H. M. Noad, Esq, To the Editors of the London and Edinburgh Philosophical Magazine. Gentlemen, T PERCEIVE by the last number of your Journal that I -*- have been anticipated in some of the remarks I had in- tended to make on the " Chemical peculiarity of Bismuth" by Dr. Schoenbein. My last communication which you have re- quested me to incorporate with the present related to phaeno- mena observable when iron wire is exposed under certain cir- cumstances to the action of diluted nitric acid sp. gr. 1*1 4* or 1 "2. The experiments described were these : — Dr. Schoenbein, in referring to a short letter of mine in the Philosophical Maga- zine of April last, (vol. x. p. 276) says, that " the facts there de- scribed are quite the same as those previously described by him- self in a letter to Dr. Faraday ;" but there is this difference be- tween them, — the Professor's experiments were made with a strong acid, mine with an acid much diluted with water ; in the one case, as is now well known, the peculiar state of iron is called forth by a variety of methods, by heat, by oxidation, by previous immersion in very strong acid, by association with platina, palladiuni, gold,&c., and, lastly, as Dr. Schcenbein has shown, by association with peroxide of lead ; but in a diluted of Iron and Bismuth. 49 acid none of these methods have a similar effect : indeed, by associating iron wire with platina, and immersing it in a glass of nitric acid sp. gr. l-l-t, I have frequently observed the action to be increased ; but though the peculiar state is not called forth by direct association with platina, it is when the vf'wQ is connected with that metal in a certain manner through the medium of a galvanometer; in proof of which I beg to call the attention of Dr. Schcenbein and other readers of the Philosophical Magazine who may be interested in the subject to the following facts, by which also it will, I think, be shown, that when in the peculiar state it is absolutely incapable of conducting voltaic electricity in a low state of intensity. 1, 2, 3, represent three glasses half filled with diluted nitric acid : from 1 proceeds a platina wire connected with one of the mercury cups of a delicate galvanometer, and from 3 an iron wire of equal length, and dipping into the other cup ; the glasses are connected by bent iron wires. Now, in acid of this strength (sp. gr. 1*14? or r2), iron wire, however thickly coiled with platina or with any other metal that I have tried, is strongly acted on, the brown oxide being instantaneously and copiously deposited ; neither is the action prevented if the platina is associated with its upper end, and dipped into the acid in such a manner that the point of junction shall be above the surface of the fluid: but if the platina wire is connected with the galvanometer, and im- mersed in the glass of acid, and the iron wire united^rs^ with the instrument^ and then dipped into the acid, it is brought to the peculiar state^ and is not in the slightest manner acted on in any length of time, nor does the galvanometer evince any signs of electrical action. Any other mode of completing the circuit is ineffectual, but 3 or 4 glasses containing a similar acid may be united by bent pieces of wire, as shown in the sketch, with a result similar to that when a single glass is employed. This very interesting experiment is one of delicacy, and without the following precautions will generally fail. 1st, The wire must be in its natural state, any attempt to clean the surface by scraping or filing destroys the peculiarity ; one drop of acid touching the surface previous to immersion does the same. In repeating the experiments lately before a number of persons, I continually failed in exhibiting the phaenomena, till I observed that the pliers with which I cut and bent the Fhil. Mag, 5. 3. Vol. 12. No. 7 1 . Jan. 1 838. H 50 Mr. Noad on the peculiar Voltaic Conditions. wires had become accidentally wetted with the acid, and it was sufficiently evident that this had interfered with the result, for when they were carefully dried the experiment always suc- ceeded. When a wire has been once used, the property is de- stroyed in it, at least for a longtime. The acid should be quite free from nitrous acid vapour, and I have found it better, in order to insure this, to heat it gently for some time, using it when quite cold, after diluting it with the requisite quantity of distilled water. Observing these precautions in all the experiments I shall here describe, I have no doubt that any person who feels inclined to repeat them will arrive at results similar to mine. The iron wire I employed was y^^^h of an inch in diameter, the platina much less. Suppose three glasses arranged, as in the sketch, before a galvanometer, the platina and iron wires immersed in their respective glasses, and connected with the instrument in such a manner that the iron shall be active. Let the iron glass be united to the one next to it by a bent wire; now take another, similarly bent, clean piece, and dip one endjlrst into the iron glass, and then gradually bring the other end into the platina glass, and it will be found inactive. At the moment of immer- sion, a slight deflection of the needle will be perceptible, but this will soon cease ; and after it has taken up its usual position, rapidly break and renew the contact of the platina or iron extreme wire with its cup : not the slightest further oscillation will ensue, which decisively proves that no electrical current is passing, although a strong one is called forth by the action of the extreme iron wire. If a bent platina wire, not larger than a pack-thread, or a strip of any other metal, is made to connect the two glasses, an immediate deflection of the needle takes place, greater or less in proportion as the metal is more or less acted on. I have repeated this curious experiment fifty times in the presence of various persons with the same result, never having been able to trace the slightest electrical current across the inactive wire, and never having met with any other metal beside that refused the passage. If the connecting wire with both ends active is now removed, and another new and clean one substituted, observing the same order in immersing its ends, the extremity nearest the platina glass will be rendered inactive, and the same will result with any number of arrange- ments. The galvanometer I have employed is a very delicate one; the needle is astatic and suspended by a single hair; it was constructed for me by Messrs. Knight of Foster Lane. When the needle of the galvanometer is quite still, let either of the inactive ends be touched at a single point with any metal on which the acid is capable of exerting an action, ' of Iron and Bismuth. SI and it will not only immediately be thrown into action itself, but all the inactive wires in the series after it will turn active also, the needle being strongly deflected; but if it should happen, as it sometimes, but rarely, does, that one termi- nation retains its peculiar state, then there will be no disturb- ance of the needle^ which is an additional and irresistible proof of the utter incapacity of the iron in that state to con- duct weak current electricity. It will be found impossible to render either end of the connecting wires inactive by com- pleting the circuit by dipping into the platina glass Jirst ; nei- ther can the terminal iron wire connected with the galvano- meter be brought into the same state unless both ends of both connecting wires are undergoing chemical action, it being absolutely necessary that there should be a free passage for the slight current which the needle shows to be produced the moment the wire dips into the acid, and on isohich current the development of the peculiar state depends. Again, supposing the terminal iron wire, or one end ofone or of both the connecting wires to be inactive, if the platina ter- minal wire is removed from its glass, and a wire of any other metal on which the liquid exerts chemical action substituted for it, the counter current which that metal calls forth through the liquid instantly destroys the peculiar state of ail the wires in the arrangement : the brown oxide appears as if by magic, and the needle is deflected. From these experiments it appears to me quite clear, that the inactive state of iron is occasioned by a voltaic current of a certain intensity passing through it in a certain direction ; and as it is impossii3le to induce such a state on wire after its surface has been abraded or previously wetted with acid, it is evident that the state of surface over which the current passes is closely connected with the phaenomenon ; it seems that it must bear a certain relation to oxygen, or, in the happy lan- guage of Dr. Faraday, be in a state equivalent to an oxidation. That a current does pass from it previously to its acquiring the peculiar state, is evident from the slight motion of the needle at the moment the wire first touches the acid ; that it afterwards stops the passage of a current altogether, is shown by the subsequent stillness of the instrument even when con- tact with its cups is rapidly broken and renewed ; and that a slight counter current is sufficient to destroy the, inactive state altogether, is shown by touching it at a single point for a mo- ment with any metal on which the diluted acid exerts an action, and in a still more interesting manner by making the extreme platina and iron wire change places. With regard to the " Chemical peculiarity of Bismuth," I H2 52 Mr. Noad ofi the Hydrates of Barytes and Strontia, quite agree with Dr. Schoenbein that it seems to belong to a distinct class of phaenomena. It differs from iron in these particulars: 1st, Platina wire will immediately stop its effer- vescing action in nitric acid sp. gr. 1*2, though it will not pre- vent its slow oxidation, as is proved by its turning black, and also by appeal to the galvanometer : the same metal will not, under similar circumstances, protect iron, as has sufficiently been shown. 2ndly, I have observed, that when bismuth has once had its action with the acid lessened, it does not regain it for a long time, even after the surface has bee?i removed by fling ; but by degrees its original character is restored : and, lastly, when substituted for the bent iron wires, as in the experiments above described, it allows the electrical current to pass quite as freely as active iron wire. These are the principal facts I have thought worth com- municating. I have made many other experiments with vol- taic piles of various sizes, but the results at which I have arrived have in general coincided so closely with those described by Dr. Schoenbein, that I shall not trouble you with a relation of them. In conclusion, however, I would strongly recom- mend those who may have an opportunity of procuring cobalt and nickel in a state of purity, and in sufficient abundance, to repeat these experiments, substituting those metals for the iron ; and I cannot help thinking, from the general chemical analogy between these three metals, that something interesting may thereby be elicited *. I am, yours, &c. Shawford. Dec. 11, 1837. * Henry M. NoAD. P. S. — I take the opportunity which this letter affords me to state, that through the kindness of Mr. J. Denhara Smith I have been furnished with some crystals of the hydrates of barytes and strontia from the specimens on which his experi- ments were made; and it is due to him and to the public to state, that the results of my analysis have agreed so closely with his, that there can be no doubt that the constitution assigned by him to these hydrated metallic oxides is perfectly correct. I have, nevertheless, repeated also the analysis of the crystals I obtained, with the same results as stated in my letter on that subject; and I can therefore only attribute the difference to the extreme difficulty of depriving these hydrates thoroughly of uncombined water. [See Lond. & Edinb. Phil. Mag. vol.ix. p. 87; vol.xi. p. 301.] • It must be recollected, however, that Professors Schoenbein and Degen were convinced, by their experiments, that the peculiar condition cannot be excited either in cobalt or in nickel. See our last Number, p. 547.— Edit. [ r,3 ] XV. A Report of the Progress of Vegetable Physiology during the Year 1836. -Sy J. Me yen, Professor of Botany in the University of Berlin,* [Continued from p. 537.] On the Structure and Growth of the more perfect Plants, IVTOHLf has published a very interesting work on the struc- ^^ ture and development of the bark in the stems of dico- tyledons, in which this subject has been treated comparatively in various plants. The experiments of Mohl are as follows : In the bark of a young branch of the cork-oak (Qiiercus Suber) four distinct layers are to be distinguished. The exterior layer is the epidermis ; it consists, as in other cases, of a simple layer of flat thick-sided cells, and is dotted with star-like hairs. (De Candolle, it is true, observes that the epidermis of trees is never covered with hairs.) The second layer lies close un- der the epidermis, and consists of 3 — 5 strata of thinner-sided cells, void of colour and of granules, which are for the most part deposited horizontally, and are also like the cells of the epidermis, rather compressed (i, e. towards the surface of of the stem). The third layer is a cellular envelope, which appears as a green parenchymatous layer of cells. In this layer of green cells appear single, colourless, rather larger cells, which contain small granules also void of colour ; a circum- stance which is also to be found in many other plants. The inner or fourth layer is the liber or fibrous layer, which how- ever is only recognised as a distinct layer in branches of some years* growth. In branches from two to three years old of this plant we find the above-mentioned layers of the bark scarcely changed : the epidermis and the second layer are un- changed ; the parenchyma, on the other hand, of the cellular envelope is enlarged ; the cells have become thicker, and we find dots on the partitions. First, in the third and fifth year, the epidermis, which can no longer follow the expansion of the bark, and in general of the mass of the young branch, ac- quires small cracks, and now a great change takes place in the layer of cork situated under it. This layer, which at first was so small, enlarges on the inner side by depositions of new layers. The new layers consist, like the old ones, of thin- sided colourless cells, but He with their longer diameter of their length in the direction of the bark. With this continual in- crease in size of the interior layers, the exterior ones split, and * From Wiegmann's Archiv fur Naturgeschkhte, 1837, Part 3. Trans- lated by Mr. Wm. Francis. t Observations on the development of cork, and of the bark on the rind of arborescent dicotyledons. — Tubingen, 1836. 54 Prof. Meyen's Report of the Progress of give to the stem an irregular rugged surface. The sub- stance thus originated is the cork, which, as is well known, is applied to such various uses. We can perceive in every cork that its increase took place in layers; and that at the limits of the two layers the cells become rather smaller, and with thicker membranes, from which circumstance these spots appear darker, just as the external ends of the annual rings of the Conifera;, We may always perceive that the annual rings in the wood of trees also exhibit very various and thick layers, that they are often irregularly deposited in thick masses. In cork this is by far more the case. In the cork-oak the bark falls off' every eight or nine years, and is taken off" some years sooner for useful purposes. De CandoUe is of opinion that it is the cellular envelope which is here developed. With this development of the cork substance in consequence of age, the development of the third and fourth layer goes on at an equal rate ; the cellular envelope however increases but in a small degree, and without the formation of new layers, while the groups of colourless cells, which often contain cry- stals, increase more and more in circumference. The inner layer develops new fascicles of liber, and the cells situated between the fibres are like those of the cellular envelope, in which, as Duhamel had previously stated, they are immedi- ately continued. Dutrochet* has published some observations on the forma- tion of the cork substance ; he especially directs attention to the fact that the increase of this mass takes place towards the interior, as in the corneous tissue of animals. Dutrochet also finds it very necessary to determine closely the external enve- lope of the bark, and in this he follows the statements of Brongniart, since he divides the epidermis into the cuticula and the cellular membrane. I stated my own opinion on this subject in a recent memoir in the second part of this ArcJiiv, The development of the cork substance in Acer campestre is quite similar : here it arrives at perfection even in the first year, immediately after which the epidermis splits at various points. In this case then the development of the cork proceeds very rapidly, but it also ceases sooner than in the cork-oak, and in later years the two other layers of the bark are then developed in such a manner that there gradually re-originates a certain symmetry between the individual layers. In other cases, as for instance in Banksia serrata, we also find four cortical layers ; but here it is especially the cellular en- velope that enlarges, while the cork substance and the fibrous * Formation du Lxkge.—UIrutitut, No. 192. Vegetable Physiology for the Year \^*6Q, S5 layer remain, as in general, quite undeveloped, and here, especially at the base of the trees, the bark is often more than twice as thick as the ligneous body. From these few in- stances we already see that the increase of the bark in thick- ness, even in cultivated plants nearly related to each other, may consist of the predominating development of quite dif- ferent cortical layers. The bark of the birch is well known from its peculiar structure and its various colours. The young annual branches of this tree also possess an epidermis, which is covered with fine hairs : under this is situated a small layer of tabular cells, which represents the cork layer, and directly covers the cellu- lar envelope. This cellular layer appears at the surface as soon as the epidermis falls off (in the second or third year) ; the single cells then become brown, and new layers of cells are deposited on the interior surface of this cellular mass. This mass now forms the well-known birch bark, which con- sists of thin white lamellae, which we can peel off one after the other. Mohl proposes to give this cellular mass the name of Periderma, while the external layer is known by the name of Epiilermis. If we examine the bark from the stem of an old birch we find that it consists of a great number of brown layers, which, as in the leaves of a book, lie one over the other, and are very easily stript off. They are clothed on both surfaces with a white covering, which consists of very thin-sided colourless diametrically deposited cells, which are rather less compressed than those of the brown layer, where the cells are very thick- sided and filled with a brown substance. From the eighth to the tenth year there is for the first time alternately deve- loped in the birch along with every layer of the brown cork tissue, at the same time a white layer, which consists of larger and more delicate cells; until this period the formation of new layers only takes place on the one surface of the Peri- derma, The white and the brown substance of the bark of the birch seem to be more distinct masses than those in the cork, where the borders of each layer may also be distinguished by their different colours. (See the anatomical difference of these layers in the figure which Link has given in his Icon, AnaL Bot. Tab. vi. fig. 13.) Very remarkable is the difference between the cork sub- stance of the cork-oak and the brown whitish layers of the birch bark, since these remain for a long time attached to the stem without cracking, and gradually peel offj while the cork substance splits and falls off. The inner layers of the birch 56 Prof. Meyen*s Report of the Progress of bark consist of the cellular envelope and the layer of liber : the intermediate parenchymatous cells are very thick-sided. (See the figures of the development of the birch bark which Link has given in the Icon, Anat. Bot. Tab. vi. fig. 12, 14-, and 15.) In the very thick bark of old birch stems the afore-mentioned regularity in the position of the brown and white layers is not observable ; but the increase in thickness takes place here and there in a higher or lower degree, by which the previous per- fectly regular concentric laminae are bent and torn in various ways. We have already mentioned those cases which show that the distinct development of the bark consists sometimes in the thickening of the cork substance, at others in the thicken- ing of the cellular envelope ; there are however many cases in which the great development of the bark substance consists chiefly in the development of the layer of liber ; we may cite for instance the beech (Fagus sylvatica). In this tree the bark almost always remains even ; the cellular envelope here always remains very small, even when the bark has become of considerable thickness. The bark also of the plane-tree {Platanus occidentalis) which is found in this country must also be specially mentioned. It exhibits the same structure as the bark of the beech, remain- ing, however, in this state only from the eighth to the tenth year. About this time there forms in the layer of liber, i. e. only at some places, a delicate layer of tabular cells which agree exactly with that of the periderma. This new layer of periderma is so situnted that a part of the bark substance is completely separated by it, which then gradually dries, and after gradual disunion, actually falls off. These new forma- tions of new layers of periderma are repeated, and thus follows the continual delamination, by which the tree still retains a very even bark. The great scales of bark, which fall oiF, consist, however, of the cellular envelope, and of a portion of the substance of the liber. The scales of the bark in Frunus, Pj/rus, Crataegus, Quercus Robur, Tilia europcjea, &c., are said to originate in the same manner as in the plane tree. Mohl, with other botanists, distinguishes these thick inner layers of the bark of the cork, which are formed in quite a different manner, and calls the inner laye: the rugose bark (rhytidoma, from pung a wrinkle). The results of these observations are, that the origin of the scales of the surface of the bark of dicotyledonous plants is not to be sought for in a desiccation of the bark layers, and in a mechanical splitting of them, but that it depends on Vegetable Physiology for the IVar 1836. 57 the later development of distinct cellular layers, which dis* unite the single bark scales, or prepare for their disunion, or even themselves form the scales. Upon the whole, we may suppose two main differences in the later development of the cellular tissue of the bark; in the first case the layers are developed outside the cellular envelope, and in the other, the becoming thicker arises from the development of a stratum of cells under the cellular layer; in the first case it is generally cork substance which is formed in the second bark {rhytidoma). There are besides a number of plants in which anew layer of liber is annually formed, while the old layer dies away and peels off, for instance Vitis xnnifera, Lonicera Caprifolium. The bark of dicotyledons consists therefore, as has been de- monstrated in the cases specially examined by Mohl, of three distinct layers, of very different structure, besides the epider- mis. The exterior stratum of cells, which in many cases change into a thick corky substance, is called by Mohl the cork layery stratum suherosum sen phlceum. Link* calls this layer Epi- jihloeum, outer rind {oberrinde); while he designates the inter- mediate rind Mesophlceum and the inner rind Endophlceum, The latter may evidently be compared with the layer of liber of other botanists, and the intermediate rind with the green cellular layer, the so-called cortical pith of many botanists. Mohlf has also published some very interesting observa- tions on the occurrence of suberose tissue in the stems of monocotyledons. Link and Dutrochet have also in their late works before cited, admitted the occurrence of the su- berose tissue in the rhizoma of Tamils Elephantipes. Ac- cording to Mohl's microscopical observations it appears that the brown layer of cork in Tamus Elephantipes perfectly agrees in its structure with the cork of dicotyledonous trees. The layer of cork on the basis of the stem consists only of a few layers of tabular cells, which form regular rows perpen- dicular to the surface of the stem. The exterior layers are brown, and have died off; the inner layer situated near to the rind is full of sap, colourless or yellowish. The thick layer of cork which surrounds the convex part of the stem is composed in the same manner as the cork of the cork-oak, of thin-sided cells which form regular rows per- pendicular to the basis of the rind, etc. A distinction between the rind and the cork can only be made in so far that the rind is living, whereas the cork on the contrary is dry and dead ; • PhU. BoL, p. 282. I Observations on the Rhizoma of Tamus Elephantipes L. — T'u' bingeuy 183G. Phil Mag,, S.3. Vol. 12. No. 71. Jan. 1838. I 58 Prof. Meyen*s Report of the Progress of the cork does not consist liere, as in the dicotyledons, of a di- stinct hiyer, but rather of the layers of rind which have died off. Many excellent memoirs have again appeared upon the structure and design of the peculiar formations of rind, which are now known under the name of lenticular glands. Mohl* has enlarged his former observations on this subject, and has especially noticed the relation of the lenticular glands to the diJFereiit layers of rind. The lenticular glands are evident on branches of even one year's growth beneath the uninjured epi- dermis ; at a later period, sometimes towards the end of the first year, at other times after some years, the epidermis over the lenticular glands splits open in a longitudinal direction, and the lenticular glands then make their appearance as little warts. Subsequently they extend, artd they then appear as diagonal stripes; where however the rind is thrown off, the lenticular glands also fall off. The lenticular gland, says Mohl, lies between the epidermis and the green parenchyma of the rind, and consists of greenish or colourless cells, (some- times it has a different colour, as for instance, a yellow in Ber^ beris, and a red one in Sambucus nigra) which lie in rows, having a position perpendicular to the axis of the branch, are for the most part smaller than the cells of the green paren- chyma of the rind, and unite towards the interior with it. In many plants the cork layer of the rind, or its exterior paren- chyma, is said to take a collateral part in the formation of the lenticular glands, so that it consists, properly speaking, of two layers, that is to say, of one belonging to the green paren- chyma of the rind, and of one which consists of the exterior parenchyma of the rind, or combines with it. Hence, as well as from various other circumstances, Mohl places the forma- tion of the lenticular glands parallel with the production of cork ; nay, he supposes that the lenticular gland is a partial cork formation, which owes its existence to the concretion of the inner parenchyma of the rind. For my own part 1 cannot agree with these views. Obser- vations on this subject have shown me that the lenticular gland always consists in a concretion of the green layer of rind, and that this concretion is only surrounded by the exterior paren- chyma of the rind ; it is true, however, that there also takes place a disjunction in the parenchyma, which forms the ex- terior, and almost always reflexed margins of this enveloping brown layer of rind. The cells of the lenticular glands, which lie exactly in the middle, and which are distinguished from all others by their length, generally lose by degrees their green • Observations on the Lenticular Glands. — Tubingen ,1836, 4to. Vegetable Physiology for the Year 1836. 59 colouring, and at last become quite white, as the green con- tents gradually disappear. These middle cells stand with their extended longitudinal axis quite horizontal ; whereas the cells of the lenticular gland, which form its exterior layers, generally retain not only their usual form, but also more or less their green colouring. If the entire formation gradually dries, its cellular membranes become more or less coloured ; and in this colouring only has the tissue of the lenticular glands any resemblance to the formation of cork. Mohl once more notices in this memoir the opinion which De Candolle has diffused so generally, that the lenticular glands were to be considered as it were root-buds, an opinion which we find in almost all the recent popular writings on vegetable physiology, although this position ought long since to have been abandoned. Unger also, in his very interesting dissertation on the design of lenticular glands*, states that these organs only occasionally stand in connection with the cortex ; but they are not in any respect, according to Unger, " espe- cially theexterior flat-pressed cells of the cortex only, i. e., those which are united by a gelatinous mass (materia inter cellular is) to a kind of integument (z. e, the external layers of the cortex) those which take any part in this metamorphosis," but the whole formation proceeds from the green layer of cortex, and breaks right through the external integument, just as Unger has cor- rectly figured it in the above-mentioned memoir. Unger thinks that the first momentum of the formation of the lenticular glands is a concretion of the wide-pressed cells of the exterior layer of cortex. The concretion begins with the increase in size of the single cells ; the increase in size causes a loosening of the concretion, and its final consequence is a complete separation. A nominal increase of cells is said to take place from the intercellular matter (!), and in this may principally be the proximate cause of the bursting of the upper layers of cells. Unger has very well observed that the cells which form the interior of the lenticular gland separate from one another, and seem as it were to make themselves independent. (Where then in this case has the intercellular matter remained, which is said to inclose these cells?) When the concrete masses are very great, and do not pulverize, they form great warts, such as we can point out on JLuonymus verrucosus and others. Unger enumerates various other vegetable formations, where he recognised an analogue to the formation of lenticular glands, in order perhaps in this way to be able to unravel their real design. In the first place are mentioned as such analogous formations, those remarkable organs which Von Martius dis- * Flora of 183G, pp. 577 to 604. 12 60 Prof. Meyen's Report of the Progress of covered on the stems of the tree ferns, and of which mention was made in our Year's Report for 1834, in which I already suggested that it was possible to explain the cells of these or- gans as impel feet nuclei [?J, (Brutkorner.) In the Lichens it is theSoredicCy and in thejungermannice the leaves bearing the re- productive granulations, which are regarded as formations ana- logous to the lenticular glands of the more perfect plants. "The design of the lenticular glands evinces itself," says Unger, "un- doubtedly in the clearest manner in the formation of the im- perfect buds of the Jungermannice, and hence we might form the supposition of explaining the lenticular glands as efforts to con- tinue on the cortex of dicotyledons the formation of imperfect buds." Unger however thinks that a far greater design lies at the bottom of all this; he observed that the lenticular glands de- velop themselves on young shoots oi Prunus Padus and Si/ringa indgaris exactly at those places where the stomata rarely occur, and therefore the lenticular gland may stand in some way in con- nection with the respiratory process ; nay, he would even con- sider them as obliterated respiratory organs. 1 must also ex- press a similar opinion as to the design of the lenticular glands ; I consider them not as obliterated respiratory organs, but as formations, by means of which an open communication is made, intermediate between the exterior air and the intercel- lular passages of the green layer of cortex. In this latter tissue intercellular passages are very frequent; but the firm combination of the cells in the exterior layers of cortex do not allow in the old state of the plant of any uninterrupted communication. Link* also contends that the lenticular glands belong tcf the cortical formation, that the temporary roots, on the con- trary, originate from subjacent wood ; yet it cannot be denied that they break out for the most part near to these warts, as also do the shoots. Very interesting is an observation of Eudes-Deslongchampsf on theefFect which the circular decortication produces upon the vegetation of a tree ; similar experiments it is true have been previously made with the same results ; but the present one of Eudes-Deslongchamps, which was performed on a beech, has been observed very carefully. The wound of the cortex which went round the whole circumference of the stem was nearly a foot wide, and the vigorous tree seemed not to suffer in the least by it. On the surface of the decorticated vood were to be seen many irregular exudations which had • Elcm.Phil.Bot.,^.2H\. t I^els de la decortication circulaire sur uti Heire. — VInstitut de 1836, p. 314. Vegetable Physiology for the Year 1886. 61 a similar appearance to the cortex. The upper edge of the wound exhibited towards the end of the summer a large swell- ing, while that of the lower Q(\gQ. of the wound had consider- ably diminished. In the next year the leaves developed themselves earlier on this tree than on such as had not been wounded. In the beginning the tree was still very strong, but in the course of the summer it shrunk, the leaves remained small, and the development of the shoots was very inconsider- able. The exudations on the surface of the decorticated lig- neous body became drier, and in the third year were quite dry. In the beginning of the third year the tree once more shot forth, but the leaves remained small, etc. In the begin- ning of the fourth year the tree was dead. I have made the same observation on the hardy stem of an alder tree, which also died in the fourth year, but did not exhibit any exuda- tions on the cleansed surface of the ligneous body, which seems chiefly to take place when the decortication has been performed very late, for instance in July*. Dutrochetf has published some new observations on the growth of coniferous stems ; the notices, however, on this subject which we have seen in the journal cited are too short for us to be able to judge of it with any certainty. We hope that Dutrochet will soon describe this interesting subject more in detail. HenslowJ has described two cases in which the dead ligneous bodies of dicotyledons have been gradually inclosed by new annual rings, similar to those cases which have been described by Du Petit- Thouars and Lindley. In one of the cases described, namely, in the stem of a poplar, it was only one half of the surface of the stem, which had probably died from decortication, and the ligneous layers of the next annual ring had gradually deposited themselves laterally over the decorticated place, so that so soon as the fifth year the wound was closed, and the new ligneous ring again surrounded the whole stem. Cases of this sort are however extremely frequent, especially in willows, when in trimming, some branches are cut off, the ligneous body of which is then covered with new ligneous layers by a side branch. Some new observations of Giron de Buzareingues § on the * A notice of Mr. Nevin's recent experiments on the same subject was given in our last volume, p. 553. — Edit. f Accro'issement en diametre du Pin us picea. — VInstitut de 1836, p. 427. \ On the disunion of contiguous Layers in the Wood of Exogenous Trees. Jardine's, Selby's, and Johnston's Magazine of Zoology and Botany. Lon- don, 1 836, i. p. 32. § Mem. sur V accroisscment en grosseur des Exogenes. — Cojnpt. Renducs, 1836. 6$ Prof. Meyen*s Report of the Progress of composition of the young ligneous layer have been published, the results of which I cannot exactly determine; we shall however notice this more fully after the publication of the en- tire memoir. Corda* has published a general treatise on the stem of plants : ^' the work," says the author, " was written in the year 18iJ3, and laid before the Royal Academy of Sciences of Berlin in the beginning of 1834. It originated from MohPs splendid work on palms, and from the truths disclosed in this, compared with my previously (!) made observations." Corda received from the Royal Society of Berlin the honourable request to demonstrate how, and in what manner, palms and the plants related to them grewf . In order to solve this ques- tion Corda proposed to himself a series of problems, which he has endeavoured to answer one after the other in the present memoir. For the solution of the first question, whether the externally evident formations and anomalies of the stem are continued towards the interior, or whether and how the inner condition exercises any influence on the formation of the ex- ternal form ; Corda treats of the growth of Coniferce, Cycadece^ and ferns, etc. He compares the ligneous body in very dif- ferent anamorphoses of the dicotyledonous stem, and also finds that it agrees in structure. Corda does well in re- marking how in Cactus RogeniX a ligneous cylinder originates from a blending of the ligneous bundles, similar to that in the stems of arborescent ferns, which was fully mentioned in our last year's report. Corda thinks he is able to say of Pelargo- nium zonale, that the ligneous body of the youngest branches is similarly constructed to that of the herbaceous ferns, that of the older branches to that of firs, and that of the basis of the stem to that of deciduous trees. I would however here ob- serve, that the ligneous body in young coniferous stems, or in young branches of these plants, is circumstanced exactly as in the young branches of Pelargonium ; for the single ligneous bundles stand in both perfectly separate. Corda, after having referred in Dracana^ Elais and other palms to a ligneous cy- linder similar to that in Coiiifera, formed by a blending of the ends of the ligneous bundles, answers the first question negatively. The second question, whether all forms of vegetation can occur in one and the same plant, Corda answers quite as we should expect, and shows that in all plants a peripherical and * On the structure of the vegetable Stem. Prague, 583G. f In our last volume, p. 553, will be found a notice of some experiments, to ascertain the internal structure of the wood of palms, by Mr. Gardner. — Edit. I It takes place in all woody Cactecs, Meyen. Vegetable Physiology for the Year 1836. 6S terminal vegetation takes place. This however was known to Mohl, since he represented i\ievegetatio terminalis as different from the vegetatio 2^sripherica ; and he took these ideas quite in a different sense from that indicated by Corda ; Mohl ap- peared merely to err in so far as he ascribed only a vegetatio terminalis to the Cycadece, whilst they are circumstanced ex- actly as the ConifercE, The third question, what relation does the shoot of one year bear to the stem of many years' growth, and the fourth question, whether all annual and perennial plants of the same class grow similarly, have found their answer in the preceding ones. The fifth question, whether all exogenous or peripherically growing plants push forth the new-formed parts like new plants, between the liber and the ligneous layer of the older, is treated very fully, and the answer is: " All plants growing peripherically push forth their new parts in a fissure of the liber, and never between the liber and the wood ; the side of the liber (the inner side of the fissure) produces new liber ; whilst a part of the old liber becomes actually part of the wood, and produces new wood on its exterior side." In re- gard to this statement, I would refer only to the demonstra- tions of some celebrated phytotomists, that the structure of the cells of the liber and that of the cells of the wood is very different, and that hence alone this position falls to the ground, whilst it can be positively refuted in various other ways. The sixth question? whether the young stem or part thereof grows differently from the old ; and the seventh, whether and how the terminal vegetation of Mohl exists and goes on, are also answered in the first replies; yet the eighth question, whether a consistent and universally applicable distinction of the vegetation of monocotyledonous and dicotyledonous plants can be demonstrated, is answered negatively; The ninth question. How do mosses, lichens, algae, and fungi grow, and can the above questions be in any degree ap- plied to them, has also been previously answered in part ; and Corda remarks, that every new cell is formed at the exterior surface of the older ones, which, however, as I have in the beginning of the present memoir explained, is not correct. Finally, Corda has formed thirty conclusions, which he offers to physiologists for their opinion and critical examination. I will here only mention those which differ from the present prevalent views, as, 1. All wood must be formed in a parenchymatous tissue, which tissue is separated, by means of the originating ligneous mass, into two parts, at first alike, subsequently of an opposite nature, the interior one of which we call wood, the external one cortex. 64- Prof. Meyen's Report of the Progress of 2. All wood consists of a combination of liber and vessels which belong to the air-productive system. The liber is the osseous system, the spiral and dotted vessels are the tracheal system of the vegetable organism. 3. The liber is always formed earlier than the vessels. 16. It has also been supposed and taught, that the wood of ConifercE consists in the older annual rings entirely of vessels ; however, we find in each, even in the oldest annual ring, a very thin layer of liber, which has been overlooked on account of its thinness. 19. Liber and wood independently, and the combination of both parts in their yet soft condition, is called alburnum. 20. There also originates, with every new ligneous layer, a new thin stratum of parenchyma, at the exterior surface of the new liber and interior side of the old, which at first is full of sap, and subsequently passes over into suberose tissue, and imparts to the dead rind the brown colour; whence we also find in the cortex layers formed, which consist alternately of liber and cork, &c. Link * has published a series of excellent observations on the uninterrupted and interrupted growth of wood in the stem, as also on the growth of the leaves and root, which conclude with a treatise on the anamorphoses of the stem and of the root, which forms one of the most excellent parts of this new edition of the Philosophia Botanica. This subject has nev^er been treated of so specially and with such a profound knowledge. In a beautiful work also of G. Meneghinif several species of monocotyledonous stems are anatomically characterized with great accuracy, and explained by figures. I must how- ever content myself with calling attention to these treatises, as their contents are too voluminous to be given in this place. I will here only give in full the results from this work of Meneghini, which he himself has given in p. 77—86. '' Two ascertained facts," says the author, " in the vital ac- tivity of monocotyledons, led me, in the observation of their structure, to the conclusions, 1st, that, where certain currents of vital saps exist, there also are vascular fibres formed ; and that, 2ndly, certain curvatures are impressed on the interior vascular fibres, by means of the displacements of the append- ages of the stem from which these fibres are suspended." Meneghini proposed to himself for solution the following problems : 1. Which is the arrangement of the vascular fibres that is common to all monocotyledonous stems ? • Elem. PhU. Bot. Ed. alt., p. 288—299. t Ricerche sulla Struttura del Caule nelle Piante Monocotiledoni. Padua, 1836, fol. niin. Vegetable Physiology for the Year \?>^Q, G^ In every monocotyledonous plant there may be detached from the basis of each leaf a greater or smaller number of vascular bundles, which run, in their manifold, slanting and extended course, near to any point of the axis, and from thence, separating from one another towards the horizontal side, continue to descend right and left with various contortions, continually returning in a slanting direction towards the peri- phery. They end by taking a perpendicular course, which allows of their condensing themselves into a peripherical zone of various firmness and thickness, in which, however, the same r)rder of superposition is always retained ; in return for which the most recent bundles are always placed upon the others. 2. What invariable laws govern this general arrange- ment? Since each leaf, at its origin from the stalk, comes forth with a circular basis in the middle of the bud, and is carried in its growth like a spiral line to a higher and peripherical spot, as it continues to surround the whole circumference of the stalk; and since, in consequence, it can only embrace a gradually smaller arc, it necessarily must follow that the lower course of each vascular bundle represents the place which it occupied during the time when the leaf was still inclosed in the bud ; and the upper organized course, during the progression of the leaf itself, gradually depends on the conditions, as modifica- tions of an invariable law, which are observed in this process. 3. To what particular modifications can the general and constant type of this organization be subjected? The bud, which gives origin to new individuals, ceases to develop itself as soon as it has arrived at a certain limit, or continues in an indefinite manner its progressive development. The limit of the first is fixed by the terminal position of the inflorescence, which in the second is an axillary one. The florescent part of the stalk is held fixed by the upper courses of the vascular fibres, and enjoys therefore the conditions in- herent in them, which are -those of endogenitiveness. The centripetal or centrifugal characters of the inflorescence itself cause in the structure of the inflorescent part only a slight mo- dification, which is still less evident in the lower parts of the stalk, and is connected with the period of the development of the axillary bud, whence originate the inflorescent branches. The separation and displacement of the leaves is effected as it were in a single or in two spiral lines, which run round at the same time in opposite directions. The greater or less per- pendicular distance, and the greater or less lateral divergence of the leavesj (setting aside the relation of the basis to the Phil. MafT, S. 3. Vol. 12. A^o. 71. Ja?i. 1838. K 66 Prof. Meyen's Report of the Pjogress of circumference of the stalk,) uniformly retained or gradually diminished, and the constant order of their succession round the stem, are properties which modify by their change these two general cases. The greater the perpendicular distance of the leaves is, the less is the slanting course of the vascular bun- dle. If the proportion of the basis of the leaf to the periphery of the stalk has remained, then the horizontal inclination of the fibre only is uniformly and constantly impressed at the very time of the displacement of the leaves. But when the insertion is limited to a single arc, this inclination becomes by so much the greater as that is lessened ; since the fibres must deviate, some to the right, others to the left, while they remain diffused with the lower courses over the whole peri- phery. The shorter however the insertion is, and the smaller the vertical distance, the less is the lateral divergence of the leaves, which even goes so far as to imitate a whorl, and even to form one. If, on the contrary, the original proportion is preserved, the lateral divergence depends only on the per- pendicular distance, and then the distichous arrangement often remains, which is the natural one in the monocotyledons. Thus it happens in the case of the double spiral lines, and the changes of this peculiarity alone afford proof of the diversity of the structure from the continuous stem to the articulated, from the solid culm to the tubular. 4. What part do the branches take in the structure and growth of the stalk ? The branches that constitute the axillary inflorescence, and which originated and grew at the same time with the leaves, have their vascular bundles also in the same direction, and contribute very little to the growth of the common stem. The scanty data which science possesses respecting the rami- fications of Pandanus justify the supposition that they have the same origin as the inflorescence. If, however, a fresh system succeeds the first, on account of the terminal inflores- cence, whether it be that it proceeds from a single branch or from several kinds around the same horizontal surface, it in- clines itself upon the old one, and there forms all around a layer, which may be compared with the annual vegetation in dicotyledonous stems. Independent of this, branches may originate on the already developed parts of the stem, in regard to which two different properties may be noticed. For it may happen that the vege- tation of the main axis is completed or interrupted, and the productions of these branches externally belong to the fibrous ligneous body of the old stem ; or that this continuous grow- ing and the new productions combine and interlace with those Vegetable Physiology for the Year 1836. 67 of the branches. These several kinds of ramification also contribute in various ways to the enlargement of the stem. It must be entirely ascribed to this, if they follow the already completed vegetation of the main axis; they only take a small part in it, when they rise from the inflorescence to the angle of the leaves then present. We must establish similar distinctions with regard to the roots ; for when they hang down from the basis of the stem, their vascular bundles are continued ; when, on the other hand, they break out from the lateral parts, they send forth their formations of vascular bundles between the ligneous body and the exterior layer of cortex. 5. What new distinctive characters are established by means of these organic properties between the stems of the two great classes of phanerogamic vascular plants ? A parenchymatous cellular tissue, through which vascular bundles run longitudinally, forms the organization of the stem of a dicotyledonous, as well as of a monocotyledonous plant in the first periods of life. The internal structure and the relative arrangement of these fibres must remain subjects of comparison. As to the structure, Mohl proved that it is the same in both classes. We find in the monocotyledons as in the dicotyledons, on the inner side of the vascular bundle, which is directed towards the axis of the stem, a chain of vessels, which form a part of what is called by Hull corona ; by botanists of the present day medullary sheath in the wood of dicotyledons. The exterior side of the bundle is on the other hand occupied by prosenchymatous cells, and these are those which in dicotyledons form the liber. Lastly, be- tween the inner ligneous layers and the exterior bundles of liber is another bundle of distinct vessels, which in its pro- portion is variable, and at times is even wanting in dicotyle- dons. In this the indicated structure is still the same in the whole course of the single ligneous bundles; different, how- ever, in the various progressions of its course in the stems of monocotyledons. The direction also of the ligneous bundles in these plants is different at different points of the stem, while in the dicoty- ledons they descend perpendicularly, and always parallel with one another. Great diversity may however be remarked during the progress of vegetation. In the monocotyledons the constant isolation of the fibres allows of every one of them re- peating, with each fibre, in their two courses, the same pecu- liarity reversed ; the more recent the upper course, the nearer K2 68 Prof. Mey(?n\s lieport of the Progress of is 4t placed to the axis of the stem, and the lower to the peri-* phery. In the greater number of dicotyledons the isolation of the vascular bundles is retained, and consequently the integrity ot the original proportions only up to a certain period. Ac-r cording to the genera each bundle ends more or less quickly, in such a manner that they arrange themselves with their sides upon each other, and the circle of vascular bundles becomes now a firm tube, which is traversed solely by radial laminae, formed by series of horizontal cells. The new bundles, which continue to be organized, after this tube is closed, increase its size, so long as the vegetation of the year continues. If, there-? fore, we divide the apex of a young germ, we see that the vas- cular bundles which pass into the leaves constantly proceed from the internal layer of wood. These fibrous vascular formations were distinguished by Girou de Buzareingues ac- cording as they belonged to the leaves of the young germ, or to the buds which are developed in the angles of those leaves. He showed that these buds, notwithstanding their apparently more interior position to that of the leaves, rise out of the summit of a more projecting medullary production; and that their vascular bundles, allowing a passage to those of the leaves, descend on the exterior side of the first fibrous body. Both of the two zones, therefore, are formed by several small concentric layers; those of the external ring are always ar- ranged so that those that Jire for the most part peripherical belong to the lowest buds ; the most interior, on the contrary, to the highest ones. Thus it is also with the central zone in annual plants in the shoots of the Rhizocarpcu, and for the greater part also in the new shoots of trees ; but in some of the latter the arrangement is just the reverse, by which the fibres of the upper leaves are exteriorly over the others, ^nd those, above all, nearest to the central point, are those which belong to the inferior leaves. The column of pith in this c«nse takes an obverse conical form, while it has that of a straight cone in the first instance. Mohl does not distin- guish these two cases, nor the two zones as distinct and exclusive productions of the leaves and of the buds. He concedes tliat in the aj)ex the lecent fibres are organized in the interior of the older ones ; and he brings forward various data in order to overthrow Alph De Candolle's explanation of the crampons (?) (Wurtzcl-fasscns)^ which would jireserve, on that ground only, to the monocotyledons the name of Endogens. But in the inferior parts, heib\nid in the dicotyledons a nature so . X -\^ cos

the =" to the extremity thereof must be fl?"- r^ (cos cof b^ r' (cos <^f c^ r^ (co: a^ _ r^ "^ 6^ -r' '^ c' - when o), ^, ^^ denote the < es between the radius vector r, and the axes of j:, y, z, so that the =^ may be written a' x^ b' v' a^ _ r^ ^ b^ -r^^ = 0, which has been found to be that of the wave-surface. But we have seen that „. = e^(eos(4-')y+a'(sinCii-')y .-. the =" to the wave surface may be written where <, iy< denote the < es between the radius vector v and the two lines which would be the optic axes if at, b, c were changed into — , -,-, — so that if e be the inclination of either to the mean axis of elasticity Phil. Mag. S. 3. Vol. 12. No. 71. Jan. 18S8. L 71 Mr. Sylvester's Analytical Development / (W "" ^\ a // fc2 - cs \ sm . = ^ I -,— P I = - y ( -^— ^) These lines I shall call by way of distinction the prime radii*. Cor. (1.) If r, 7-2 be the two values of r corresponding to the same values of ^^ »y, we have sm (, . sm I. which proves the celebrated problem of two rays having a common direction in a crystal. Cor. (2.) The intersection of any concentric sphere with the wave surface is formed by making r constant. Hence */ i *// becomes constant, and .*. ^ ij :t '^ ^ii — constant. Hence the curve of intersection is the locus of points, the sum or dif- ference of whose distances from two poles when measured by the arcs of great circles is constant ; the poles being the points in which the prime radii pierce the sphere. In three cases these spherico-ellipses or spherico-hyperbolse become great circles: 1°. When »^ -j- * = the angle between the two poles, in which case the curve of intersection is the great circle which comprises the two poles. 2^. When »^ — i = 0 when the locus is a great circle per- pendicular to the former and bisecting the angle between the optic axes. 3°. When i, + * = 180 when the locus is a great circle perpendicular to the two above, and bisecting the supple- mental angle between the two axes. Various other properties may be with the greatest simplicity deduced from the radio-angular equation. The hurry of the press leaves me time only to subjoin the following Proposition. "To find the inclination of the radius vector to the tangent plane, in terms of the angles which the radius vector makes with the prime radii." ♦ Upon the authority of Professor Airy I have appropriated the term optic axee to the linei normal to the fronts of single velocity. of Fresnel's Optical Theorif of Crystals. 75 Let O be the centre of the wave-surface O A, O B the two prime radii, O P any radius vector. Let O P = u, P O A = <^, P O B = i^p and let the inclination of the planes P O A, POB = /x , ,(-i"^)' (-^)' then -5- == r^ a* c (taking only the positive sign for the sake of brevity.) Let O Q, O R be the two adjacent radii vectores, so as- sumed that QOA = POA QOB = POB + 8*/, ROB=POB ROA=POA-f8i; and let p^ q, r, a, b be the projections of P, Q, R, A, B on a sphere of which O is the centre, then it is clear that qpa=z9(f rpbzrz 90° draw q m perpendicular to pb , then p m = li^ pm and .*. pq = . = ^ ^ smpqm In like manner pr = Now the angle Q P O ^ -1 r.POQ ^ =-(^-^)(-'"^')(~H^) p m sina pb siiiju. 8'/ sm/x -1 r . pq ' d,7' .8,, d «y^ dr rd T* /I 1 \ .•.cot.QPO = ~ . y^- -^)sin(»;-f *).sin|ic In like manner cot. RPO = — . y-^ --^jsin(i^ + 0-sin^ .-. Q P O = R P O. L2 76 Mr. Sylvester's Analytical Development Also it is clear that rpq=apb=fj^. And to find the inclination of O P to R P Q, we have only to describe a sphere of which P is the centre, and in- ^' tersecting P Q, P R, P O in Q', R', O'. Then F O' Q' = /it, and O' Q' = O' R' Draw O' N perpendicular to R' Q', then O' N measures the in- clination of the radius vector to the tangent plane *. And Q' CK N = 4 .-.cos 4 =tanO'N.cotO'Q' •. cotO'N = cot . O Q' cos -' and .-. cot O' N= i r\ [^ - ^ sin ^ . sin (,^ + ,^,), let A O B the angle between the optic axes = 2 ^, then by mere trigonometry "° "o" = V/ • : i V sm /^ . sin i^^ .'. the tangent of the inclination between the radius vector and the normal \u c* / V g,n i^ . sin i^, Q . E . F. In like manner the inclination between the same radius vector *ind the normal at the other point of the wave-surface pierced by it = i (r.)'(\ - -t) «i" ('/ - '.) • V — ^^ - ^-^ '^ ^ '' \ tt* c* / ^ ' '"^ V sm I, . sini^, * O' is the projection of the ray and R' O' of the tangent plane. There- fore O' N being perpendicular to R' Q' represents their inclination. o/* Fresnel's Optical Theory of Crystals. 77 We may, in the same way, find the inclination of the tan- gent plane to either of the prime radii, and to the plane which contains them both, in terms of i^ and i^; the former by a re- markably elegant construction ; but the final expressions do not present themselves under the same simple aspect. If we call 4> the angle between the ray and the front, we may still further reduce by substituting for r^ its values in terms of i^ ^^^ and we shall obtain 2 (c^ - a^) cot = — ^ ' ea.tan^^4-^'+fl^cot^^ ysi„(. + '^±^')si„(.-'-^). cosec .'. tan P O I = sin i jtA . OPx = tan rfOP sin/u* ^TOP cos I /A ^1. d I, and O I = O P . sec POL Also the position of the plane P O I is known, and .*. the radius is completely determined in magnitude and position. It may be worth while also to remark that the above construc- tions enable us to form a series of equations between the magnitude of the radius and its inclinations to the two prime perpendiculars. In fact, if we call ^t^ tt^, the two inclinations in question cos TT^ = cos P O I cos i, + sin P O I sin /^ . sin -i- cos IT// = cos P O I COS in -}- sin P O I sin €rhaps the fourth magnitude being seen through it." [See Lond. and Edinb. Phil. Mag., vol. x. pp. 206, 494.] 02 100 Hoyal Irish Academy » suing year : — President, Rev. Bartholomew Lloyd, D.D * ; Trea- surer, Tliomas Herbert Orpen, M.D. ; Secretary, Rev. Joseph Hen- derson Singer, D.D. j Secretary to Council, Rev. Richard Mac Donnell, D.D. ; Secretary of Foreign Correspondence, Sir William Betham ; Librarian^ Rev. William Hamilton Drummond, D.D. Committee of Science. — Rev. Franc Sadleir, D.D., Rev. Richard Mac Donnell, D.D., Sir William Rowan Hamilton, Rev. Humphrey Lloyd, James Apjohn, M.D., James Mac CuUagh, Esq., Captain Portlock, R.E. Committee of Polite Li^em^wre.— The Archbishop of Dublin, Rev. Joseph Henderson Singer, D.D., Andrew Carmichael, Esq., Samuel Litton M.D., Rev. William Hamilton Drummond, D.D., Rev. Charles Richard Elrington, D.D., William West, M.D. Committee of Antiquities. — Rev. James Henthorn Todd, Thomas Herbert Orpen, M.D., Hugh Ferguson, M.D., Sir William Betham, George Petrie, Esq., Rev. Caesar Otway, Dean of St. Patrick's. Professor Kane read a paper, entitled *' Researches on the Com- binations derived from Pyroacetic Spirit." In order to understand the relation between the following bodies and pyroacetic spirit, the atomic weight of the latter must be consi- dered as representing four volumes of vapour, and its formula written C(5 Hg Oy. It has been found to give a series generally analogous to that of ordinary alcohol, and Professor Kane proposes for it the name Mesitic Alcohol. By means of sulphuric acid there is obtained a colourless fluid, of an alliaceous odour, boiling at 276. F. and having the composition Cg H4, to which is given the name Mesitylene. By acting on mesitic alcohol with perchloride of phosphorus there is gQnQr?i\.^ phospo-mesitylic acid, and a compound fluid heavier than water, which has the formula Cg H5 C/j and, by the decomposition of the latter by means of potash, a body Cg H^ O. These may be considered either as containing Mesitylene, or a hypothetic radical Mesityl, thus : CgH4 + HO.Hydrate of Me- sitylene. CgH^ + O. Oxide of Mesityl. Cg H3 + CI. Chloride of Mesityl. Cg H4 + H CI. Muriate of Mesi- tylene. By the action of phosphorus and iodine on mesitic alcohol, there is produced an iodide of mesityl, having the formula Cg H^ I. Oxide of Mesityl unites with sulphuric acid in two proportions, forming the sulphate and the bisulphate of mesityl ; both of these are acid, and unite with bases forming well characterized salts. The salts of the former are called sulphomesitylates, and of the latter persulphomesitylates ; and a very anomalous character in these salts is, that the quantity of the inorganic base is such as could neu- tralize the whole of the sulphuric acid which they contain. Thus the sulpho-mesitylate of lime has the formula ♦ Dr. Lloyd having since deceased. Sir W. Rowan Hamilton has been elected President in his place. Royal Irish Academy. 101 SOs + CeH^O + CaO + HOj and the persulphomesitylate of lime 2S03 + C6H30 + 2CaO + HO. . When an excess of phosphorus is used in the process for making iodide of mesityl, there is obtained in ihe retort a white matter in silky crystals, which dissolves in water, is very acid, and forms well characterized salts, which, when heated, take fire and burn with a well marked flame of phosphorus. This acid is termed hypopfiosp/iomesi- tylous acid 'j and the formula of the hypophosphomesity late of baryta \s P^O + CgH^O + BaO + HO. In the decomposition of mesitic alcohol by perchloride of phospho- rus there is obtained an acid which gives a soda salt crystallizing in rhombs which contain water of crystallization. Their formula is P.O. + NaO + CgH.O + SHO. Professor Kane stated that he had obtained also the aldehyd of of the mesityl series, as well as bodies procured by the action of chlo- rine and iodine on mesitylene, and the acids which are generated by the oxidation of mesitic alcohol, the history of which bodies shall form the subject of another paper. The empyreumatic oil, which is produced in small quantity when mesitic alcohol is prepared by distilling acetate of lime, has been sub- mitted to analysis by Professor Kane, and its composition found to be C,o Hg O. It therefore belongs to the family of which oil of tur- pentine is the base, and is polymeric with camphor, and the pinic, sylvic, and copaivic acids*. Dr. Apiohn read a paper " On the Specific Heats of the Aeriform Fluids." ^ The first part of this communication was an analysis of, and some critical remarks upon, the labours of those who had preceded the author in the same investigation, particularly those of Dulong. Dr. Apjohn's own method was then detailed. In a paper read by him before the Academy in April, 1835, the equationf/"=/— 1?^ + -^ was proved to include the solution of the dew-point problem. But the factor a in this expression, which is obviously equal (when the air or gas is dry, or in other words, when/"=0) tO'Z-^ x — , is the spe- 4Sd p cific heat under a given volume of the gas which is supposed to be the subject of experiment. Hence if/' and d be determined for the various aeriform fluids by observation, their relative capacities for ca- loric can be compared. Such is the principle of the method. Two distinct series of experiments were then detailed, from the second of which, as comprehending those which he conceives to be most accurate, the author has deduced the following table of specific heats : * In this abstract the atomic weights are taken, Hydrogen = 1. Oxygen = 8. Carbon = 6- 13. t d=t—l' the difference of the temperatures shown by a wet and dry thcrmonioter, and/' is the elastic force of vapour at temperature t'. 102 Royal Irish Academy. Specific Heats of equal Volumes. Atmospheric Air, I '000 Nitrogen, 1-048 Oxygen, (by calculation,) -808 Hydrogen, 1 '459 Carbonic Acid, 1*195 Carbonic Oxide, -996 Nitrous Oxide, I'193 Dr. Apjohn conceives himself justified in drawing from his researches the following conclusions : 1°. All gases have not under equal volumes the same specific heat. 2°. This law is not even true of the simple gases. 3°. There does not appear to be any simple relation between the specific heats of the gases, and their specific gravities or atomic weights, A paper was then read '^ On some remarkable Salts, obtained by the action of Ferrocyanide of Potassium on Sulphovinates and Sul- phomethylates." By William Gregory, M.D., F.R.S.E., &c. When ferrocyanide of potassum is added to sulphovinate of lime, a precipitate appears, which, when heated, gives off hydrocyanic aether. This salt (called A) contains iron, calcium, potassium, cyanogen, and the base of aether. The mother liquid is found to contain a salt B, very soluble in water and alcohol, which also, on being heated, yields hydrocyanic aether. The ingredients of B are sulphuric acid, potash, aether, and cyanogen. In order to avoid the confusion which might result from the use of a salt of lime, (as Mosander has shown that ferrocyanide of potas- sium produces in the salts of lime, generally, a precipitate consist- ing of iron, calcium, potassium, and cyanogen,) the author next tried sulphovinate of potash. By the action of ferrocyanide of potassium on this salt he got a salt C, corresponding to A, but different j and another salt D, identical with B. When sulphomethylate of lime was employed, two salts E and F were obtained, exactly analogous to A and B : and by employing sulphomethylate of potash he got G, corresponding to E, and H, identical with F. As it seemed likely that the study of any one of these reactions would explain all the rest, the author began with the analysis of G and H, of which he had a larger supply than of the others. G is lemon yellow, transparent, soluble in vwter, insoluble in al- cohol, crystallizing in square tables much resembling those of ferro- cyanide of potassium. By exposure to a heat of 212°, it loses 13*5 per cent, water of crystallization, and becomes opake. More strongly heated it is decomposed, giving oft' hydrocyanate of methy- lene, = Cc2 H3 Cy or Me Cy. The analysis corresponds with the for- mula 4KCy, 3 Fe Cy, M Cy, 8 Kq. H is white, very soluble in water and alcohol, crystallizing in square shining tables. It closely resembles sulphomethylate of potash. Royal Irish Academy. 103 but differs from it in being anhydrous, in containing cyanogen, and in yielding hydrocyanate of thylene when decomposed by heat. Its analysis agrees with the formula 6 SOgjSKO, MO,MCy If 3 equivalents of ferrocyanide of potassium be supposed to act on 3 of sulphomethylate of potash there is the following equation : 3 equiv. Ferrocyanide 3 equiv. Sulphomethylate 6KCy,3FeCy + 6SO,3KO,3MO = 1 equiv. G 1 equiv. H =4KCy,3FeC2/,MC^ + 6 S 0^,3 KO, M O, M Cy + 2 K O. i. e. 2 equiv. potash. In conformity with this explanation, the liquid in which G crystallizes is alkaline. If this explanation be admitted, it will of course apply, mutatis mu- tandis, to the salts A B, C D, E F. The author, however, is not yet satisfied that the salts which he analysed may not have been mixtures, perhaps in definite proportions. No doubt can be entertained that new salts have been formed, but the close resemblance between their properties and those of the salts which yield them, renders the task of purifying and analysing them one of great difficulty. April 10. — A paper was read '* On a new variety of Alumn," by James Apjohn, M.D., M.R.I.A., Professor of Chemistry in the Royal College of Surgeons, Ireland. This paper commenced with a brief description of the physical cha- racters and chemical properties of the mineral in question, which was found about GOO miles to the north of the Cape of Good Hope, near Algoa Bay, where it occurs in strata whose aggregate thickness is about twenty feet. The specimen described is composed of transpa- rent threads or fibres, exhibiting a beautiful silky lustre, and in ap- pearance closely resembling satin-spar or the finer forms of amianthus. In taste, solubility in water, and other properties, it corresponded with ordinary alumn. It was also easily shown to contain sulphuric acid and alumina, but in addition it contained a base which, though precipitated like alumina by potash, was notredissolved by an excess of the alkali. This, upon examination, turned out to be protoxide of manganese. There was no alkali, but about one per cent, of sul- phate of magnesia. In the first attempt at effecting the analysis of the mineral it was foimd that alumina and protoxide of manganese could not be sepa- rated perfectly by potash, as some of the oxide was taken up by the alkali, while a considerable quantity of alumina was left behind with the oxide. The author explained a method of overcoming this diffi- culty, the particulars of which are given in detail in the paper. Tiie following are the results — the numbers in column (2) being the quotients got by dividing those incolumn(l) by the respective atomic weights : (1) (2) (3) Sulphuric Acid, 3279 '8 i 7 4-000 Alumina, 10-65 -414 2026 Oxide of Manganese, 7*33 '205 1*003 Sulphate of Magnesia, 1-08 Water of Crystallization, .... 48-15 5-350 26-315 100 104' Royal Irish Jcadcmj/. The numbers in column (3) being almost exactly the integers, 4, 2, 1, and 26, show that the substance analysed is a true alumn, having, as respects its acid and bases, the same formula (0SO3, AL O3 + SO3, MnO + 26HO) with all the known species of that genus, and the same number of atoms of water with soda alumn. It differs from all those previously known in containing no alkali, this being replaced by protoxide of manganese. As an additional peculiarity Dr. A. observed that it did not appear susceptible of assuming the octohedral lorm. The paper concluded with some remarks upon the probable exist- ence of an alumn containing no metal but manganese, and upon certain difficulties in the doctrines of isomorphism, suggested by some of the varieties of this class of salts. Captain Portlock brought under the notice of the Academy some peculiar habits of the Otus Brachyotos or short-eared owl, lately ob- served by Captain Neely, whilst collecting for the Ordnance Survey of Ireland. This species of the sub-genus Otus being migratory, is much rarer than the Otus vulgaris or long-eared owl, and it differs from it in many striking respects, such as the small size of the elongated feathers, commonly called ears, (which in this species can only be discerned when the bird is living,) and in its tendency to diurnal habits. But in the instance now recorded it exhibits other peculiarities of habit which afford a still more remarkable line of distinction. The point of Magilligan, forming the Derry side of the opening of Lough Foyle to the sea, is studded at its extremity with numerous sand hillocks, in which the rabbits burrow and the sheldrakes lay their eggs, as in other similar localities. But here a new occupant for the burrows of the rabbits appears in the Otus brachyotos. These birds are regular their autumnal appearance, and are seen to sit at the openings of the burrow-holes, and to run into them when disturbed. Captain Portlock having directed further attention to the fact, and pointed out the necessity of guarding against any source of fallacy, the truth of the first statement was fully established, more than one having been shot on emerging from the holes, and another actually caught in a trap at the mouth of a hole when endeavouring to make his escape, 'i'his interesting fact naturally recalls to recollection the Striv cunicularia of America, described by Say ; and Captain Port- lock pointed out the great value of characteristic traits of habit in elucidating classification, and suggested the peculiar importance of those described in his paper, in affording a link of resemblance be- tween the Strix cunicularia and the Otus brachyotos, and thereby faci- litating the determination of the true place, in natural classification, of the former, hitherto considered doubtful. The Secretary communicated the substance of a paper " On the Conic Sections ■" by James Booth, Esq. The methods hitherto adopted in deducing the central and focal properties of the conic sections, from arbitrary definitions, having appeared to the author defective in geometrical elegance, he has en- deavoured in this paper to derive them from new definitions, of which the following may be considered the principal : Royal Irish Academy, 105 1. If two spheres be inscribed in a right cone touching the plane of a conic section, the points of contact are called/oci. 2. The radical plane of these two " focal spheres " intersects the major axis in a point called the centre. The property from which the definition of a focus here given is de- rived, although known for several years, has not been hitherto ap- plied further than to show that this point is identical with the focus as usually defined. By the help of the above definitions, and of the simplest elemen- tary principles, the central and focal properties already known have been deduced, generally in one or two steps, and several new theorems have been likewise discovered in the development of the method. A paper '* On Fluorine;" by G. J. Knox, Esq., and the Rev. Thomas Knox, was read by Dr. Apjohn*. The authors having taken a summary view of all the researches on fluorine up to the date of the commencement of their experiments in April, 18.36, proceeded to describe the vessels of fluorspar which they used in their first experiments, and exhibited those which were lat- terly found best adapted for examining the gas. These vessels were of fluor spar lapped with iron wire for the purpose of equalizing the temperature, so as to prevent the vessels from splitting on a sudden application of heat. In place of a flat cover for the vessels, fluor spar receivers were used, the cavities of which were filled with ground stoppers of the same material. On moving the receivers over the mouth of the vessel the stoppers fall in, and their places are occupied by the gaseous contents of the vessel. On the top of each of the vessels is placed a flat slab of fluor spar, which answers the purpose of a table, upon which the receivers of the gases can be moved. On the slab are four small depressions, in which are placed the substances upon which the action of the gas is to be observed, and over which the receivers when filled with the gas, can be slid. In opposite sides of these receivers are drilled holes, into which are fitted, air-tight^ clear crystals of fluor spar, through which the colour of any gas in the receiver may be distinctly observed. The vessels are supported on a stand over a lamp. On heating pure fluoride of mercuryin these vessels with dry chlorine the authors obtained a colourless gas, (as seen through the fluor,) having a heavy smell not pungent or irritating, and thereby easily distinguished from chlorine or hydrofluoric acid. When exposed to the air it does not fume, as would be the case were the slightest trace of hydrofluoric acid present. The inside of the vessel is found coated with crystals of corrosive sublimate. The gas does not extinguish ignited phosphorus or red-hot iron wiref , and consequently is (as Sir H. Davy conjectured) a supporter of combustion. It detonates • SeeLond and Edinb. Phil. Mag., vol. ix. p. 107- t The non-extinction of ignited iron-wire in a gas cannot give evidence of its capability of supporting combustion. — Edit. Vhxl, Mag, S, 3. Vol. 12. No. 71. Suppl. Jan. 1838. P 106 Royal Irish Academy. with hydrogen, forming hydrofluoric acid. Placed over water, the solution (if such) has all the properties of hydrofluoric acid, i. e. acts on glass, reddens litmus, and gives precipitates with lime andbarytes. Placed over dry litmus and Brazil wood paper, the former is reddened, and the latter turned yellow 3 in no instance are they bleached. When a receiver of the gas is placed over wet glass, the glass is strongly acted upon ; when the glass is carefully dried, the action is not so strong as before. When a small piece of dry glass is placed in a perforation in the interior of the receiver, the glass is acted upon, but not more so than when fluoride of mercury alone is in the vessel, from which they conclude that fluorine does not act on perfectly dry glass. To ascertain the action of the gas on metals they found it necessary to try the separate effects of hydrofluoric acid, sublimed fluoride of mercury, and bichloride of mercury, in order to distinguish the action of fluorine from that due to the vapour of these substances. For this purpose bismuth and palladium at a moderate heat, and gold at a high temperature, aftbrded distinguishing tests. To determine the relative attraction of fluorine for those metals upon which it does not act except at high temperatures, they used as positive poles of a bat- tery of sixty pairs of plates, moistened fluoride of lead, palladium, pla- tinum, gold, and rhodium. The palladium and platinum were always acted upon, the gold occasionally, and the rhodium never ; from which they suppose that fluorine might be obtained in an insulated state, by electrolyzing fluoride of lead in a tube of fluor spar, using rhodium as the positive pole. They were unable to repeat M. Baudrimont's experiments in glass or fluor spar vessels*. Supposing that the gas he obtained was an oxide of fluorine, they heated in a dry glass tube iodic acid and flu- oride of mercury ; supposing that since iodine decomposes fluoride of mercury, the oxygen and fluorine being set free from their combinations with oppositely electrical bodies (iodine and mercury), would be in the most favourable condition for combining. On the application of a moderate heat a pale yellow vapour rose in the tube, which did not act on the glass, and bleached litmus. Mr. Mallet read a paper " On an hitherto unobserved Structure discovered in certain Trap Rocks in the County of Galway." The town of Galway is built upon a part of an immense trap dyke, which extends under the sea and to a considerable distance up Lough Corrib. Large excavations for a dock are now making in this rock at Galway, and aftbrd a convenient opportunity of examining its structure. It separates the limestone on the east (which it tilts up) from the syenite of Cunnemara on the west, (which it overlies or min- gles with.) Many fragments of both adjacent rocks are found in an altered state imbedded in the trap 5 which with the tilting of the limestone, prove the deposition a true dyke. The mass of the rock consists of greenstone, Sp. gravity 2*87, of a * See Lond. and Edinb. Phil. Mag., vol. ix. p. 149. i Royal Irish Academy. 107 dark green, but frequently veined and mixed with many other mi- nerals. In the centre of the exposed portion of the dyke rises a large vein of nearly white hornstone, presenting very interesting characters. It contains no imbedded minerals, and is homogeneous in structure, but with a lamellar or pseudo-crystalline arrangement. Its planes are vertical, and at its junction with the trap it is moulded to it, but not adherent, and appears to have been formed from rocks at a greater depth than the trap, and ejected through it. The minerals found imbedded in this trap rock are various ; specimens have been obtained of mica, chlorite, felspar, albite, olivine, augite, amphibole, epidote, apatite, adularia, chalcedony, sulphate of lime, probably anhydrite, baryto-calcite, arragonite, calcareous spar, fiuor spar, galena, iron pyrites, sometimes magnetic. Epidote is found also on Mutton Is- land. The general mass of this trap rock possesses a hidden nodular structure, only developable by blasting. The nodules consist of pre- cisely the same material as their matrix, and having the same cohe- sion, they cannot be detached by the hammer. The nodules are from eighteen inches in diameter to the size of a nut J they are sometimes found pressed together in masses with flat sides, like bubbles. Crystals occurring at the surface of a nodule do not pass into the matrix, but are truncated thereby. In some cases the nodular structure is gradually obliterated, and the usual homo- geneous one replaces it. This nodular formation is essentially different from any hitherto described, — as the orbicular granite of Corsica and South of France, the onion stone of the causeway, &c., in which the nodule and the matrix are of different materials. The present structure would appear to have been produced by the ejection of the trap in a fluid state under the sea ; masses of which cooling in their passage fell again into the liquid bed, and being enveloped, were heated nearly to the temperature of the mass, and so adhered without losing their outline. Where several fell together, and were exposed to subsequent pres- sure, they would present the flattened appearance before described ; and when more deeply enveloped, and thus subjected to a higher temperature, the nodular structure would again vanish by their com- plete fusion. It is even conceivable that the most capriciously varied parts of this and other trap rocks may owe their origin to the soldering to- gether of nodules of heterogeneous matter, projected from different depths, or at different times, or subjected to successive coolings and heatings. Professor Kane read a paper entitled ** Researches on the Com- pounds derived from Pyroacetic Spirit." (Second Series.) When dry chlorine gas is passed into pure mesitylene, Cg H4, mu- riatic acid is given off and a compound body, solid, in white prismatic crystals, is formed, giving on analysis the formula Cr, H3 Cl. A yellow substance obtained by the action of iodine on nascent mesitylene, but in too small a quantity for analysis, is considered to be Cg H3 1. P2 108 Royal Irish Acade7ny. When mesitylene is tietUed with nitric acid copious red fumes are given off, and a very heavy thick fluid obtained which gives on analysis the formula C<; H^ O^. This fluid absorbs ammonia, and forms there- with a compound soluble in water, and giving with most metallic so- lutions insoluble precipitates. If pure mesitic alcohol be heated with nitric acid, there is a very violent reaction, and an explosive decomposition, if distillation be attempted ; but by diluting with water a heavy fluid is produced, which gives on analysis, unsatisfactory results, owing, in the first place, to its decomposing with an explosion when heated, and secondly to its being always mixed with some of the substance last described : the results obtained indicate however as very probable the formula C6H3NO,. To connect the above results, Professor Kane proposes to assume as radical the body Cg H3, to which he gives the name of pteleyU Then Cg H4 = Cg H3 + H. Hydruret of pteleyl or mesitylene. Cg H3 CI = Cg H3 + CI. Chloride of pteleyl. Cg H3 1 = Cg H3 + I. Iodide of pteleyl. Cg H4 0.2 = Cg H3 O + H O. Hydrated oxide of pteleyl, the alde- hyd of the mesitic series. Cg H3 N 0^= Cg H3 O + N O3. Hyponitrate of pteleyl. The compound heavy liquid produced by the action of chlorine on mesitic alcohol, was found to differ but little from the description given by Liebig. Its formula, as given by Dr. Kane's analysis, is Cg H3 O2 C/2 ; and by the action of bases it yields a metallic chloride, and a salt of a new acid named by Professor Kane Pteleic Add. This has not yet been analyzed, but theory indicates for its composi- tion the formula Cg H3O4. By the action of permanganate of potash on mesitic alcohol, there is generated a neutral salt of potash containing an acid, to which is given the name of the Perpteleic, whose salts generally decompose themselves with facility into carbonates, and a salt of another acid to which the name of the Acetonic Acid has been applied. The consti- tution of these last three acids remains yet to be fixed by other expe- riments, the author confining himself in the present paper to the suggestion of that view of their composition, which, in the absence of positive analyses, seems to him most likely to be true. Professor Kane exhibited to the Academy a balance made by a German artist, having some peculiarities of construction and ad- justment. April 24.— A paper was read by Professor Kane ** On Dumasine, a new Fluid Substance isomeric with Camphor." This fluid is obtained in very small quantity in the distillation of acetate of lime for preparing mesitic alcohol. It boils at 24-8°, is colourless, and of a powerful resinous smell. Its composition by ana- lysis is C,o Hg O. Thus : Royal Irish Academy, 109 Experiments. Theory. Carbon, =78-82- 7930] Hydrogen, = 10 46 - 10-35 > 10000 Oxygen, = 1072 - 10*35 J The specific gravity of the vapour of this liquid was found to be 5-204, air being 1. The theoretical density from the formula above given is 5-315, and one atom forms two volumes of vapour. It has, therefore, the same density as camphor, and like it may be considered as consisting of 1 volume of vapour of oil of turpentine, = 4*7643 I volume of vapour of oxygen, = 0*55 13 1 volumeof vapour of dumasine, =5*3156 Professor Kane read some passages of a letter from M. Dumas, of which the following is an extract: '•**** The researches, of which you have given me an account*, promise the happiest results for science, I cannot too much encou- rage you to complete them j you will see by the journals that I have communicated your letter to the Academy of Sciences, where it met with the most honourable reception. Allow me to add, that M. Peligot and myself had obtained the carbo-hydrogen, Cg H4, as well by sulphuric acid as by anhydrous phosphoric acid. We had found that potassium gave the product C^ H3 O, which you have obtained in another manner, but we were stopped by the composition of the sulpho- mesitylate of baryta, of which you have given the explanation. These researches have been made some time, but other matters caused us to neglect them, and I do not now regret it, since they are in such good hands. * * * * " ****** I announced yesterday to the Academy the existence of tlie carbo'Vinate of potash, which is C0.,+ C4H,0 + C0,. I also obtained, conjointly with M. Peligot, the carbo'tnethylate of baryta, which is Ba. OCO^ + C.HgO-f-CO^. In these bodies the acid changes very readily into carbonic acid and alcohol, or pyroxylic spirit ; and it is remarkable, that to form them it is sufficient to pass carbonic acid into a solution of baryta in spirit of wood, or of potash in ordinary alcohol. I do not doubt but that similar bodies can be obtained with pyroacetic spirit, but I shall leave to you the pleasure of isolating them. * * * * *'****! shall communicate next Monday to the Academy, some observations which may interest you more than any other person ; I mean on compounds very analogous to double chlorides, and which I have obtained by means of urea and the alkaline chlorides. Such bodies appear to me decisive on the theory of the amides. * * ♦ * " Sir William Betham read a paper" On the Affinity of the Phoenician and Celtic L-anguages, and on the Cabiri and their Mysteries." * On pyroacetic spirit. See Lend, and Edinb. Phil Mag., vol. x. p. 488, and the proceedings of the Academy for April 10 above. Prof. Kane's First Series of Researches on the same subject will be found at large in vol. x, p. 45 et ^cy.— Edit. 110 British Association, Sir William Betham then added a short notice of a Hindoo Legend from a paper in the Asiatic Researches, by Captain Wilford, showing that the Cabiric mysteries existed in India, under the names Cubear or Cuvera, Asyoruca, Asyotcerso, Cashmala and Carmala ; and that these deities or genii superintended mining and metals. Professor Mac Cullagh read a paper *' On the Chronology of Egypt." BRJTISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE : MEETING OF 1837, AT LIVERPOOL. Section of Mathematical and Physical Science, Sept. 12. Dr. Robinson, of Armagh, read a Report of the Determination of the Constant of Lunar Nutation from a discussion of the Greenwich Observations. The author commenced by giving a sketch of the commencement of accurate astronomy, under the auspices of Bradley, by his brilliant discoveries of the aberration of light and the nutation of the earth's axis, demonstrating, that a degree of precision, until then deemed unattainable in astronomical observations, was perfectly possible. The impulse then given has not since ceased to effect the movements of astronomical discovery. Yet from this day, it must be acknow- ledged, that, in regard to both aberration and nutation, nothing was added to the researches of Bradley, until within a few years, when Struve, Brinkley, and Richardson resumed the inquiry. He then sketched the progress of each of these, and stated, that the constant of nutation deduced by Brinkley was that generally adopted by Bri- tish astronomers. In Germany, however, the authority of Bessel had introduced and given currency to a different value for this important element of calculation, deduced from the calculations of Von Lin- denau; and although the two values differ only one-fourth of a se- cond, which is less than the millionth part of the length of the tele- scopes generally used in observing, yet such is the accuracy required in the modern researches of astronomy, that even this evanescent quantity of error is considered as a disgrace. This stigma, he trusted, was now removed by the work which the aid of the British Association had enabled him to perform, and of which he now intended to give a brief notice. Dr. Robinson then referred to the labour of reducing observations, as actually taken, in consequence of the refraction of light, tlie aber- ration of the stars caused by the progressive propagation of light, the proper motions of the stars, and the united effect of all the movements impressed with the earth upon the actual place of the observer. Of these, the impressions upon the axis of the earth are pre-eminent, and the largest of them in amount has been long known under the name of the Precession of the Equinoxes — this is well known both as to its laws and amount ; the remaining three are termed Nutations, of which one completes its course in a fortnight, and is never so large as one-tenth of a second — the theory of this is sufficiently known j a second completes its cycle in half a year, and when greatest may British Association, 111 amount to half a second, and has been separately determined by the admirable observations of Dr. Brinkleyj the third is the largest in amount, being about 9", and completing its cycle in the time of a complete revolution of the moon's nodes, or about eighteen years, rather more : the exact determination of this vi^as the object of the discussion of the observations of which he was now giving an account. He then proceeded to give a general description of the method of employing the observations, and the kind of observations to be se- lected for this determination, showing that it was most important to have a complete series of observations extending through the entire period of the moon's nodes, made with the same instruments, and if possible, by the same observer, or at least with the same system of observation. The observations made at Greenwich under the super- intendence of the late Mr. Pond were those selected. The tables of Bessel were usedj his values of declination, nutation, and proper motion were used, but Dr. Robinson had used his own values of aber- ration and refraction. Upwards of 4000 observations of the pole- star above were used, and in the results more than 2000 above and below were combined to give the zero of polar distance ; the others were used to watch for and detect any change in the instrument. He then stated the principle on which the other stars were selected, viz. that their altitudes secured them from uncertainties in refraction, and that they should be such, that at least two-thirds of the nutation should exist in the direction of their polar distances -, of such stars fifteen were in the Greenwich Observation, but some of these could not be used. They afforded about 8000 results, but 6000 only were used J an accident which occurred to the instrument in 1820 ren- dered useless about 1000 of these. The mean results of these ob- servations being taken with the precautions which the paper pointed out at length, the results of some required that the value of Lindenau which is 8"*977 should be increased, while others required that it should be diminished ; on the whole an increase of 0"'257 was ac- quired, giving the result 9"*234, which differed only by sixteen thou- sandths of a second from the number selected by Mr. Baily, and used in his invaluable Catalogue. The learned author then proceeded to notice and remove certain objections which he anticipated might be made to the details of his method of reduction ; in the course of these he stated, that as the corrections of Bessel's proper motions which his work has given are all, except in one instance, negative, he in- ferred that the Greenwich circle was undergoing some progressive change of figure, making it show polar distances too great for about 30° south of zenith. If this were so, he observed, the sagacity of Mr. Airy would not permit it to be long undetected. He then read a table from these observations, showing that the declinations as ob- tained from his calculations, though they differed materially from those given by Pond himself in the Nautical Almanac for 1834', yet agreed closely with those of Bessel, thus showing, that the difference between these Catalogues arises solely from the different methods of reduction, and exciting the wish, that the British Association might lend its aid in reducing the whole of the Greenwich observations made by Pond. 112 British Association, Mr. Baily congratulated Dr. Robinson on the successful termina- tion of his labours. He stated, that it was a curious fact, that Busch, of Berlin, had, from a series of observations made by Bradley at Wan- stead, before he removed to Greenwich, computed the nutation, and given its value 9"'2347, thus differing by only 7 ten-thousands of a second from the value deduced by Dr. Robinson, although the cycle of observations was different, the instruments and places of observa- tions and the observers were all different : this was a coincidence scarcely to be equalled in the annals of science. — Sir William Hamil- ton asked some questions regarding the manner in which the obser- vations of the pole-star were used by Dr. Robinson as contrasted with the method adopted by Lindenau, and seemed satisfied with the answers which were given. He stated, that he felt great gratification at what he might almost call the complete solution of this important problem, and expressed his concurrence in the conclusion to which Dr. Robinson had come in consequence of the discrepancies between the calculated declinations and those given in the Nautical Al- manac. Mr. Russell then presented the Report of the Committee on Waves. — Mr. Robison and Mr. Russell, of Edinburgh, had been appointed at the Bristol Meeting of the British Association a Committee to prosecute an inquiry concerning the Mechanism of Waves, in which Mr. Russell had been previously engaged, and to extend their obser- vations to the determination of the effect of the form of channel and of the wind upon the tidal wave. Mr. Lubbock and Mr. Whewell had already determined by their investigations the laws of the propa- gation of the oceanic tide, but it still remained to assign the law of propagation of the tide in those shallow seas and rivers where the bottom and sides of the channel exercise the principal influence on the propagation of the tidal wave. For the purpose of determining the effect of these circumstances upon the form, magnitude, and ve- locity of the tide wave, Mr. Russell had made in September, 1836, a series of observations on the River Dee, below Chester, where that river has a form and dimensions admirably suited to the purpose. It appears that for more than five miles in length the banks of the Dee are perfectly straight, quite parallel to one another, while the depth of the channel at low water is nearly uniform throughout the whole of that length. Now, in this river there is a tidal wave of from six to fifteen feet, forming, in fact, a tidal canal of large dimensions. On this part of the river the first series of observations was made. A second series of observations was made upon the River Clyde in April and May, 1837, under peculiar advantages. On the application of Sir Thomas Brisbane, a former President of the Association, the Trustees of the River Clyde offered to Mr. Russell all the assistance at their disposal, and every facility for making observations, which they conceived to be equally useful to practical navigation as to the advancement of abstract science j and their engineer, Mr. Logan had contributed much to the success of these observations. Accurate trigonometrical surveys of the channel of the river, with correct levels and transverse sections, were obtained, and a series of simultaneous British Association. 1 1 S observations made at nine different stations on the river. A series of observations had also been made on the waves at the surface of the sea, and the series had terminated by a course of experiments made in artificial channels of different forms, for the purpose of determining the nature of the mechanism of the generation and propagation of waves, so as to determine the identity of their nature with the tidal wave. Of this series of experiments and observations the following are some of the results : — It appears that there exists a species of wave different from all the others, and which Mr. Russell calls *• The Great Primary Wave of Translation," which is generated whenever an addition is made to the volume of a quiescent fluid, in such a manner as to affect simulta- neously the whole depth of the fluid, and this species of wave is ex- actly of the same nature as the tide wave. In a rectangular channel this primary wave moves with the velocity which a heavy body would acquire in falling through half the depth of the fluid, so that In a channel about 4 inches deep, the velocity of the wave is nearly 2 miles an hour 12 2 feet deep 5|^ 3 6i 4 7f .5 8| 6 9A 7 10^1 -5th 8 11 9 jji 10 12V5th 15 15 30 20 &c. &c. It also appears that the breadth of the channel, when the depth is given, does not at all affect the velocity or form of the wave -, and Mr. Russell then proceeded to assign a general rule, by means of which the velocity of the wave might be assigned d priori for a chan- nel of any form, however irregular. The manner in which the wave was observed, was by successive reflections from opposite surfaces, so as to make it pass and repass a given station of observation, the interval being noted by an accurate chronometer j and it was stated that in many cases above sixty tran- sits of the same wave had been observed, so as to give a high degree of accuracy to the observations. The instant of the wave's transit had been observed by the reflection of a luminous image thrown down by a series of mirrors, so as to cross micrometer wires with perfect precision. For a mode of determining the length of the wave Mr. Russell acknowledged himself indebted to Professor Ste-^ velly, of Belfast. '■[ These observations having determined the laws of the propagatibri of waves on a small experimental scale, were then extended to the Phil. Mag, S.3. Vol. 12. No. 71. SuppL Jan. 1838. Q 114 British Association, analogous phaenomena of the great tidal wave. In his observations on the River Dee, Mr. Russell found that the tide wave followed pre- cisely the same laws as those in his experimental channel ; that its velocity was exactly proportioned to the square root of the depth of the fluid, that its form changed in the same manner, and the exist- ence of the same law was sufficient to account for the different rate of propagation of different tides between two given places, because a tide of fifteen feel deep would travel from one place to another at the rate of fifteen miles an hour, while one of ten feet deep would only pro- ceed at the rate of twelve miles an hour ; so that if the places were thirty miles apart, the one would receive the former tide two hours later, and the latter tide two and a half hours later than the other. The creation of a tidal bore in some places was also accounted for on the same principles j and it was evident that the means of improving the navigation of tidal rivers might be satisfactorily deduced from these principles. Similar observations had been made on the tidal wave of the River Clyde, which was found to move in strict conformity with the laws of the great wave of translation, as determined by Mr. Russell's previous experiments. The effect of the wind upon the tidal wave had been eliminated by Mr. Lubbock from the Liverpool observations, and had been denied by Monsieur Daussy in his discussion of the Brest observations. Mr. Robison and Mr. Russell had directed their observations to this also, and had ascertained that its effects were of the most decided character. It was, however, probable that during the ensuing year they would be able to determine the nature and the measure of these effects with still greater precision. Mr. Whewell asked several questions of Mr. Russell respecting the method adopted for taking the level of the rivers in the Dee and in the Clyde. — Mr. Russell replied, that the level of mean tide was used in the Dee, and a fixed line was taken for many miles along the Clyde. Mr. Whewell also asked how the depths were taken, and how the agitation arising from the pressure of the waves was deter- mined at various depths. — Mr. Russell replied, that the depths were taken by actual measurement, but that the pressures at various depths had only been taken on the small scale of the models. Mr .Whewell expressed much gratification at the methods of experimenting adopted by Mr. Russell ; and although some of his conclusiona seemed at present to be scarcely reconcileable with the theoretic views held on the subject, yet he anticipated that the utmost advantage would re- sult from researches so ably conducted, and trusted that Mr. Russell would continue and extend them. — Sir William Hamilton fully con- curred in the expressions of approbation which had fallen from Mr. Whewell. Prof. Powell read a paper * On Von Wrede's Explanation of the Absorption of Light by the Undulatory Theory.' Von Wrede supposes the particles of a transparent body placed re- gularly at equal distances (6), and the ether being diffused between them, a ray of light is propagated directly through the medium, but British Association, 115 a portion of each wave encounters some of the particles, and is re- flected backwards, then forwards again, and emerges along with the direct ray ; and from the retardation it has undergone it may interfere 80 as to produce darkness, if the retardation amount to an odd mul- tiple of the half-wave length (A), but brightness if an even multiple of that quantity. These effects may be confounded together in white light, and by prismatic analysis they will be seen as dark bands. The author investigated a formula for the intensity of the light so resulting. It was deduced from the ordinary view of undulations, and brought into a form including certain constant terms, together with 2 6 the factor cos 2 it — , which is so involved, that the intensity is a A maximum when the cosine is = + 1 or when 2 tt — is an even mul- A tiple of a semicircumference j and a minimum when the cosine == — 1 , or when the arc is an odd multiple of a semicircumference. Hence, if the medium be such that 2 6 = - for any ray, that ray will be de- ficient. If 2 5 be less than the value of - for the violet ray, which is its least value, there will be no absorption : if greater, some ray will be at a minimum. Let us suppose 2 6 = w A, then passing from one end of the spectrum to the other, there will be changes of intensity dependent on the changes of the cosine between the limits cos litn and cos 2*71 — ; maxima when cos= + 1, and minima when — I : the number depending on (n,) that is, on (6), which may be supposed as large as we please. This investigation applying to a simple medium, the author showed that the expression for a compound of several media, with different values of (6), will still preserve the condition of depending on the changes of the cosine, and each medium will retain its own set of maxima and minima, which will be superposed in the spectrum. Thus far the successive reflections had been considered as taking place only between two sets of particles or reflecting surfaces : the case was then investigated where several such were taken into ac- count, and a formula resulted which was more complex, but whose maxima and minima depended on exactly the same conditions. The author showed that the more regular phaenomena of absorption are completely explained by this hypothesis, and, in one instance, even proceeded with success to a numerical comparison. He pointed out also an experimental imitation of the supposed process, which was perfectly successful.* Sir David Brewster conceived that the theory of Von Wrede was entirely inadmissible. He stated many cases of absorption where there was not an appearance of reflection, as in the case of nitrous gas, which by mere changes of temperature became as black and as im- * A translation of the original memoir on this subject by M. Von Wrede will be found in the Scientific Memoirs, vol. i. p. 477. Q2 116 British Association. penetrable to light as charcoal. Sir John Herschel had also noticed many cases of absorption without any trace of reflection ; and only in the cases of some vegetable colours did he ever experience the contrary. — Professor Lloyd asked whether the changes might not re- sult from partial changes of density caused in the substances by changes of temperature ? — Sir David Brewster stated that it was im- possible there could be any change of density in the case of the ni- trous gas, as the changes in its temperature took place while its vo- lume was secured from enlargement by its being sealed up in glass tubes. At one time he was inclined to think that some chemical change might have been effected upon the glass, but the phaenomena did not long warrant this conclusion. The phaenomena of absorption could be all had from plates of partially decomposed glass, such as that which had been long buried in the earth, but this w^as a case of real opalescence. — Sir W. Hamilton conceived that the views of Wrede required the confirmation of more exact numerical exami- nation before they could be adopted; and he trusted that Sir David Brewster would give the inquiry the advantage of his great skill and experience. Sir W, Hamilton then gave an account of his Exposition of the argument of Abel respecting equations of the fifth degree. Sir Wil- liam stated that the celebrated young Swedish philosopher, Abel, whose labours (unfortunately for the cause of science) had lately terminated with his life, had at one time supposed that he had found a method of solving generally equations of the fifth degree, but soon finding that this solution was illusory, it occurred to him that perhaps under the conditions of ordinary algebra such a solution was an im- possibility ; as soon as he had started this thought he pursued it through a most intricate argument, and at length achieved what any one upon first hearing it would be apt to consider most chimerical — an H priori argument to prove that the solution of an equation of the fifth degree was, under the limitations of ordinary algebra, an im- possibility. The argument of Abel consisted of two principal parts ; one inde- pendent of the degree of the equation, and the other dependent on that degree. The general principle was first laid down, by him, that whatever may be the degree noi any general algebraic equation, if it be possible to express a root of that equation, in terms of the coeffi- cients, by any finite combination of rational functions, and of radicals with prime exponents, then every radical in such an expression, when reduced to its most simple form, must be equal to a rational (though not a symmetric) function of the n roots of the original equation 5 and must, when considered as such a function, have exactly as many values, arising from the permutation of those n roots among them- selves, as it has values when considered as a radical, arising from the introduction of factors which are roots of unity. And in proceeding to apply this general principle to equations of the fifth degree, the same illustrious mathematician employed certain properties of func- tions of five variables, which may be condensed into the two follow- ing theorems : that if a rational function of five independent variables British Association. 117 have a prime power symmetric, without being symmetric itself, it must be the square root of the product of the ten squares of differ- ences of the five variables, or at least that square root multiplied by some symmetric function ; and that if a rational function of the same variables have itself more than two values, its square, its cube, and its fifth power have each more than two values also. Sir William Ha- milton conceived that the reflections into which he had been led were adapted to remove some obscurities and doubts which might remain upon the mind of a reader of Abel's argument ; he hoped also that he had thrown light upon this argument in a new way, by employing its premises to deduce, a 'priori, the known solutions of quadratic, cubic, and biquadratic equations, and to show that no new solutions of such equations, with radicals essentially different from those at present used, remain to be discovered : but whether or not he had himself been useful in this way, he considered Abel's result as established : namely, that it is impossible to express a root of the general equation of the fifth degree, in terms of the coefficients of that equation, by any finite combination of radicals and rational functions. What appeared to him the fallacy in Mr. Jerrard's very ingenious attempt to accomplish this impossible object had been already laid before the British Association at Bristol, and was to appear in the forthcoming volume of the Reports of that Association. Meanwhile, Sir William Hamilton was anxious to state his full conviction, founded both on theoretical reasoning and on actual experiment, that Mr. Jer- rard's method was adequate to achieve an almost equally curious and unexpected transformation, namely, the reduction of the general equa- tion of the fifth degree, with five coefficients, real or imaginary, to a trinomial form ; and therefore ultimately to that very simple state in which the sum of an unknown number (real or imaginary) and of its own fifth power is equalled to a known (real or imaginary) number. In this manner the general dependence of the modulus and amplitude of a root of the general equation of the fifth degree on the five moduli and five amplitudes of the five coefficients of that equation, is reduced to the dependence of the modulus and amplitude of a new (real or imaginary) number on the one modulus and one amplitude of the sum of that number and its own fifth power ; a reduction which Sir William Hamilton regards as very remarkable in theory, and as not unim- portant in practice, since it reduces the solution of any proposed nu- merical equation of the fifth degree even with imaginary coefficients, to the employment, without tentation, of the known logarithmic tables, and of two new tables of double entry, which he has had the curiosity to construct and to apply. It appears possible enough that this transformation, deduced from Mr. Jerrard's principles, conducts to the simplest of all forms under which the general equation of the fifth degree can be put j yet Sir M^illiam Hamilton thinks that algebraists ought not absolutely to despair of discovering some new transformation which shall conduct to a method of solution more analogous to the known ways of resolving equations of lower degrees, though not like them dependent entirely upon radicals. He inquired in what sense it is true that the general 118 British Association. equation of the fifth degree would be resolved, if, contrary to the theory of Abel, it were possible to discover, as Mr. Jerrard and others have sought to do, a reduction of that general equation to the binomial form, or to the extraction of a fifth root of an expression in general imaginary? And he conceived that the propriety of considering such extraction as an admitted instrument of calculation in elementary algebra, is ultimately founded on this : that the two real equations, x^ — lQofi y^ -{■ 5 xy*= a, bx^y — XOx'^y^ -\-y^ = b, into which the imaginary equation resolves itself, may be transformed into two others which are of the forms . 5r— 10t3 + r^ f ^ = r, and — — — = t, so that each of these two new equations expresses one given real number as a known rational function of one sought real number. But notwithstanding the interest which attaches to these two particular forms of rational functions, and generally to the analogous forms which present themselves in separating the real and imaginary parts of a radical of the nth degree. Sir William Hamilton does not conceive that they both possess so eminent a prerogative of simplicity as to entitle the inverses of them alone to be admitted among the instru- ments of elementary algebra, to the exclusion of the inverses of all other real and rational functions of single real variables. And he thinks, that since Mr. Jerrard has succeeded in reducing the general equation of the fifth degree with five imaginary coefficients to the tri- nomial form above described, which resolves itself into the two real equations following, x''> — 1 0 j:3 y2 _|_ 5 jp ^4 _|_ ^ _« Q^ 5 x^ y — \0 x'^y^ ^ y'^ -\- y = by it ought now to be the object of those who interest themselves in the improvement of this part of algebra, to inquire whether the depend- ence of the two real numbers x and y in these two last equations on the two real numbers a and 6, cannot be expressed by the help of the real inverses of some new real and rational, or even transcendental functions of single real variables j or (to express the same thing in a practical or in a geometrical form) to inquire whether the two sought real numbers cannot be calculated by a finite number of tables of single entry, or constructed by the help of a finite number of curves : although the argument of Abel excludes all hope that this can be accomplished, if we confine ourselves to those particular forms of rational functions which are connected with the extraction of radicals. Mr. Peacock observed that the Section were scarcely aware of, and could not be too strongly impressed with the value of an at- tempt like that of Sir W. Hamilton to render this celebrated argu- British Association. 119 ment of Abel Intelligible to beginners, and even to advanced students in algebra. The constitution of most minds was such that they were anxious to run away from those subjects on which their labours could be profitably employed, and to engage themselves in the pro- secution of curious and sometimes almost useless difficulties. He exemplified the celebrated resolution of the Academy of Sciences of Berlin, that they would in future receive no more communications on the subject of squaring the circle, as a remarkable proof of the extent of this morbid state of mind ; for it was a fact that the average number of communications on this subject, when taken for many years, amounted to four annually. The rage for resolving mere al- gebraic difficulties was pretty much the same, and he, therefore, for one, felt that the gratitude of men of science was due to Sir W. Hamilton for thus giving an <$;?non argument, the obvious tendency of which was to save the laborious exertion of talent in fruitless re- search J a labour, for the employment of which such vast regions were at present opening before us in rich profusion. As it occurred to him, the chief advantage which he expected from the method adopted by Sir W. Hamilton was this : that whereas from its very intricacy the argument of Abel would be inaccessible to the ordi- nary algebraist, and a doubt therefore would always remain on his mind of the validity of the conclusion, and consequently he would be tempted even still more strongly to essay the difficulty for him- self,— the method of Sir W. Hamilton, besides making the principle and many of the steps of the argument intelligible to all, and there- fore giving a high degree of probability to the conclusion, has this peculiar advantage; that by applying the very same mode of arguing to quadratic, cubic, and biquadratic equations, it has not only proved that they are soluble by precisely the modes by which we at present resolve them, but it proves further, that they are insoluble by any other purely algebraic device. This seems to be conclusive, and must carry conviction to every mind. Sept. 13 — Prof. Lloyd read an " Account of the Magnetical Ob- servatory now in course of erection at Dublin." In bringing this subject under the notice of the Section in its pre- sent stage, Mr. Lloyd said, that he trusted little apology was required. The establishment of permanent magnetical stations has been urged by the powerful recommendation of the British Association ; and he was sure that that body would view with interest the progress of an undertaking, the importance of which was sanctioned by its au- thority. The magnetical observatory, now in progress at Dublin, is situated in an open space in the gardens of Trinity College, and sufficiently remote from all disturbing influences. The building is forty feet in length, by thirty in depth. It is constructed of the dark-coloured argillaceous limestone, which abounds in the valley of Dublin, and which has been ascertained to be perfectly devoid of any influence on the needle. This is faced with Portland stone j and within, the walls are to be studded, to protect from cold and damp. No iron whatever will be used throughout the building. With reference to 120 British Association, the materials. Professor Lloyd mentioned, that in the course of the arrangements now making for the erection of a Magnetical Observa- tory at Greenwich, Mr. Airy had rejected bricks in the construction of the building, finding that they were in all cases magnetic, and sometimes even polar. Mr. Lloyd has since confirmed this obser- vation, by the examination of specimens of bricks from various lo- calities ; and though there appeared to be great diversity in the amount of their action on the needle, he met with none entirely free from such influence. The building consists of one principal room, and two smaller rooms, — one of which serves as a vestibule. The principal room is thirty-six feet in length by sixteen in breadth, and has projections in its longer sides, which increase the breadth of the central part to twenty feet. This room will contain four principal instruments, suitably supported on stone pillars : viz. a transit instrument, a theo- dolite, a variation instrument, and a dipping circle. The transit in- strument (four feet in focal length,) will be stationed close to the southern window of the room. In this position it will serve for the determination of the time; and a small trap-door in the ceiling will enable the observer to adjust it to the meridian. The theodolite will be situated towards the other end of the room, and its centre will be on the meridian line of the transit. The limb of the theodo- lite is twelve inches in diameter, and is read off by three verniers to ten seconds. Its telescope has a focal length of twenty inches, and is furnished with a micrometer reading to a single second, for the purpose of observing the diurnal variation. The variation instrument will be placed in the magnetic meridian, with respect to the theodolite, the distance between these instru- ments being about seven feet. The needle is a rectangular bar, twelve inches long, suspended by parallel silk fibres, and inclosed in a box to protect it from the agitation of the air. The magnetic bar is furnished with an achromatic lens at one end, and a cross of wires at the other, after the principle of the collimator. This will be ob- served with the telescope of the theodolite, in the usual manner j and the deviation of the line of collimation of the collimator from the magnetic axis will be ascertained by reversal. The direction of the magnetic meridian being thus found, that of the true meridian will be given by the transit. It is only necessary to turn over the transit telescope, and, using it also as a coUimator, to make a simi- lar reading of its central wire, by the telescope of the theodolite. The angle read off on the limb of the theodolite is obviously the supplement of the variation. This use of the transit has been sug- gested by Dr. Robinson j and it is anticipated that much advantage will result from the circumstance, that the two extremities of the arc are observed by precisely the same instrumental means. With this apparatus it is intended to make observations of the absolute va- riation twice each day, as is done in the observatory of Professor Gauss, at Gottingen, — the course of the diurnal variation, and the hours of maxima and minima, having been ascertained by a series of preliminary observations with the same instrument. I British Association. I2i A dipping circle constructed by Gambey will be placed on a pijiar at the remote end of the room ; and will be furnished with a^ needle, whose axis is formed into a knife-edge, for the purpose of observing the diurnal variations of the dip. Gauss's large appara- tus will also be set up in the same room, and will be used occasion- ally, especially in observations o^ the absolute intensity y made ac- cording to the method proposed by that distinguished philosopher.* The bars are too large to be employed in conjunction with other magnetical apparatus. It is intended to combine a regular series of meteorological obser- vations, with those on the direction and intensity of the terrestrial magnetic force just spoken of; and every care and precaution has been adopted in the construction of the instruments. In conclusion, Mr. Lloyd said, that he felt it a duty to allude to the liberality and zeal in the cause of science which had been evin- ced by the Board of Trinity College on this occasion. The proba- ble expense of the building and instruments is estimated at 1000/. ; and that sum was immediately allocated to the purpose, when it ap- peared that the interests of science were likely to be benefited by the outlay. Mr. Peacock congratulated the Section upon the prospect held out to the scientific world, of having fixed magnetical observatories erected in such places as would afford the surest promise of success- ful co-operation, particularly when they would be placed under the superintendence of gentlemen so eminently qualified for the task as Professor Lloyd. He informed the Section, that an observatory for magnetical observations had been erected at Greenwich, and that little doubt need be entertained of the rapid advances which the interesting investigations connected with this important science would now receive. — Mr. Ettrick conceived, that bricks would be a very improper material for the construction of a magnetical ob- servatory. He considered the use of metals in any part of the building as highly objectionable ; even copper as fastenings or hinges to doors would not be free from injurious effect. He made some inquiries as to the mode of reading off, proposed by Professor Lloyd. — Prof. Stevelly said, that Mr. Ettrick was unquestionably right in the ob- jection urged against the use of bricks, but Professor Lloyd had dis- tinctly stated, that bricks were not to be used, and that experiments had been made to ascertain the precise magnetical influence, if any there was, of the kind of stone which it was proposed to use. It was well however, that Mr. Ettrick's observations should go abroad, for the guidance of persons not conversant with these subjects* Bricks, when built into large edifices, such as the chimneys of fac- tories, were well known to have acquired magnetic polarity : the ma- terial from which they were made must be largely impregnated with iron : the mud of rivers was the detritus from hills, whose rocks were often highly magnetic. The engineers employed on the trigo- nometrical survey of Ireland had erected a mound of stones com- • Prof. Gauss's description of hi? apparatus and mode of observing vill he fomul in Lond. & Edinb. Phil. Mag., vol. ii. p. 29L Phil. Mag. S. 3. Vol. 12. No. 71. Suppl. Jan. 1838. R 1 22 British Association, posed of basalt, to sustain thesignal-staft" whicli they had erected on tl)e highest hill, near Belfast ; the effect of that heap of stones on the magnetic needle was so great, that in walking round it the needle would veer round to every point of the compass. Prof, de la Rive having read a paper on the interference of electro- magnetic currents, in which, among other facts, it was stated that when wires of platina are employed to transmit the magneto-electric cur- rents into any solution, the abundant evolution of gas which is at first observed diminishes, and after fifteen or twenty minutes disappears j Professor Andrews, of Belfast, observed, that there was one por- tion of the detail upon which he thought he could throw some light, by mentioning a fact with which he had lately become acquainted. If the poles of a galvanic arrangement of low tension, say a single pair of plates charged with weak acid, were made to communicate with two broad slips of platina immersed in water, no action what- ever would take place; but if one of the broad slips, was replaced by a fine wire, the pole which it represented would give off" the appropri- ate gas, whether oxygen or hydrogen; but the broad slip at the other pole would give off none whatever — or whichever pole it might be connected with. Now the appearance of the gas at one pole was a clear proof that water was decomposed ; and therefore the gas which must be developed at the broad slip must be dissolved in the liquid, or otherwise prevented from assuming the gaseous form. Persons not acquainted with this fact might infer, that there was no decom- posing action exerted; when, in fact, as appeared plainly upon a more extended view of the phaenomena, there was. — Mr. Lubbock inquired, from Professor Andrews, whether the hydrogen disap- peared as well as the oxygen ; for, although water can condense oxy- gen in considerable quantities, he was not aware that any consider- able quantity of hydrogen could be so condensed. — Professor An- drews replied that either would be given off at the fine platina wire, according to the pole you made it to represent, and neither would appear at the broad plate, showing that each would in turn be dis- solved, or otherwise detained in the fluid.* M. de la Rive read a second paper * On an Optical Phaenomenon observed at Mont Blanc' When the sun has set at Geneva, it is observed that Mont Blanc remains illuminated by its direct rays for a much longer time than the surrounding mountains. This phaeno- menon is owing to the great height of Mont Blanc. But after it has ceased to be illuminated the summit of Mont Blanc sometimes reap- pears at the end of ten or fifteen minutes, less intensely enlightened than at first, but nevertheless in a manner very decided, and often very brilliant. This phaenomenon takes place especially when the at- mosphere is very pure — highly charged with aqueous vapour in an in- visible state — and consequently very transparent. The author has satisfied himself (by the exact observation of the time which elapses between the two successive illuminations of the mountain, combined • On this subject see Mr. Faraday*s observations, Lond. & Edinb. Phil. Mag., vol. iv., p. ^1. k British ^Association, 123 with the calculation of the sun's progress) that the phaenomenon is due to the rays of the sun whfch traverse the atmosphere at a dis- tance from the earth less than the height of Mont Blanc, but greater than half that height, and which arrive at rarer regions of the atmo- sphere under an incidence so great that they are reflected instead of refracted. This interior reflection is facilitated by the humidity of that part of the atmosphere which the rays traverse until they reach the point of incidence. The reflected rays falling on the snowy sum- mit of Mont Blanc produce this second illumination; and the humi- dity (by augmenting the transparency of the air) renders the illumi- nation more brilliant. Sir D.Brewster stated that he had witnessed a similar effect, though on a less magnificent scale, on the Grampian Hills ; but he had always observed that on such occasions the sun set in a red west, and that all the clouds in that quarter of the heavens were then red. — M.de la Rive replied, that the pbanomenon he spoke of only appeared wher» the sky was quite free from clouds, and, in truth, it was most brilliant when the air was very transparent in consequence of its being loaded with vapour in its elastic state. — Professor Lloyd said that the dis- tinctness and vividness with which distant objects were seen in some states of the atmosphere was quite astonishing : on one occasion he had seen from the neighbourhood of Dublin the Welsh hills from their very bases, and brought so near apparently, that he could absolutely see the larger inequalities of the surface upon the sides of the moun- tains. That the atmosphere was at the time very much loaded with vapour in a highly transparent state, was obvious from the fact that immediately after a very heavy fall of rain took place, and continued for a considerable time. — Professor Stevelly wished to confirm what had fallen from Professor Lloyd and M. de la Hive by stating that whenever the Scotch hills appeared with that peculiar vividness and distinctness, from the Lough of Belfast, the fishermen always looked upon it as a sure precursor of heavy rain and wind. A friend had in- formed him that on one occasion he had noticed this appearance while standing on the beach at Hollywood, and pointed it out to an old fisherman ; the old man immediately gave notice to all his friends to whom he had access, who instantly set about drawing up their boats and placing their small craft in more secure places ; early the next morning a violent storm came on, which did much damage upon the coast to those who had not been similarly forewarned. Thus we find that the most interesting pursuits of the man of science, and the most important concerns of man in the practical details of life, fre- quently approach, and each may lend important aid to the other. — Mr. Lubbock was of opinion, that the principal fact mentioned by M. de la Rive would receive a simple solution, if we admit the theory of Poisson regarding the constitution of the atmosphere. That eminent mathematician conceived that analysis led irresistibly to the conclu- sion that the upper portions of the atmosphere were, by the extreme cold there existing, condensed into a liquid or even into a solid : if this were so, we could easily conceive how the reflection of the light from its under suiface would re-illuminate the top of Mont Blanc after the direct light of the sun had ceased to reach it. — Sir David R2 124 British Association. Brewster expressed much surprise at hearing for the first time of this theory of Poisson, and that he should feel much obliged to Mr. Lubboclv if he would give some details of it in a separate communica- tion to the Section ; and he had little doubt but that it would be as new and as acceptable to many gentlemen as to himself. He thought that the near apparent approach of distant objects in certain states of the air, as mentioned by Professor Lloyd and Professor Stevelly, might perhaps be accounted for by supposing that on these occasions the intervening air became actually converted into a large magnifying lens. Section of Chemistry and Mineralogy, Sept. 1 3. Dr. Apjohn next exhibited a new variety of Alum, upon the sub- ject of which he had lately read a paper before the Royal Irish Aca- demy.* This mineral, which he received from Mr. Atherton, an Afri- can gentleman, was found on the eastern coast of the African conti- nent, about midway between Graham's Town and Algoa Bay. It occurs in fibrous masses very similar to asbestos, having a beautiful satiny lustre, and splitting into threads which would appear to be quadrilateral prisms. In taste, solubility in water, and relation to several re-agents, it closely resembles ordinary alum, but is distin- guished from it by containing protoxide of manganese instead of an alkali, and by not assuming the octahedral form. In symbols it is represented by (3 S 0 + Al 0) + (S 0 + Mn 0)-f 25 H O, 3 2 3 3 a formula identical with that which belongs to the entire genus of alum salts. Dr. Apjohn briefly alluded to the other varieties of alum, both those in which the alkalies replace each other, and those in which the alumina is replaced by the deutoxide of iron, chrome, or manga- nese ; and pointed out the theoretical possibility of an alum contain- ing no metal but manganese. This communication gave rise to much discussion. Dr. Fara- day stated, that a specimen of the mineral in question was given to him in London, that he had found it to contain oxide of manganese, and that on this account, and because of the absence of an alkali, he hesitated to admit it as a true alum j and that supposing, as conjec- tured by Dr. Apjohn, a double salt should be formed, in which the alumina and alkali of ordinary alum were replaced by equivalent quantities of the deutoxide and protoxide of manganese, he could not admit it to be considered as an alum at all.^ — Dr. Clarke took up a difl'erent ground, and objected to the term alum being applied to the salt in question, inasmuch as it could not be made to assume the oc- tahedral form. — To the first objection Dr. Apjohn replied, that he considered the mineral he had examined to be an alum, because, ac- cording to his analysis, its composition accorded with the general for- mula for alum ; and to the second, that the other well-known alums presented other difficulties of as great magnitude as respects the laws of isomorphism. That e. g. soda alum crystallizes as an octahedron, ♦ See p 203. British Association. 125 though soda is not usually considered isoniorphous with the other aU kalies ; and that, though the different varieties of alum assume the same form, they are not by all chemists considered to contain the same amount of water of crystallization. — Professor Johnston concluded the discussion by suggesting, that the difficulties which had arisen might be easily surmounted, simply by gentlemen agreeing upon a definition of what did or did not constitute a true alum. Section of Geology and Geography, Sept. 13. A paper by Mr. Henwood was read, *0n some of the Phae- nomena of Mineral Veins in Cornwall.* This gentleman has for several years examined these phaenomena in that important mining district, often at great personal risk, and has from time to time communicated to the geological world many extraordinary facts which he had determined. He brought before the Section his present statement, in the shape merely of a question for solution, as important to the Cornish mining interest. In mines veins are often heaved out of their regular course, and are traversed by cross courses, causing further irregularity. It was a desideratum of the first importance, that a law should be determined by which a heaved vein could again be discovered ; and the opinion of geologists vvas requested on this point. In Cornwall, it is also the opinion among miners, that veins are of contemporaneous formation with tie rocks containing them, which opinion is opposed to that of geologists in general, who consider veins, in most cases, as caused by disruption from mechanical force. Mr. Henwood exhibited a diagram of heaves in the mines of Dolcoath and Huel Prudence, which he submitted to the Section for solution by means of mechanical movement. He him- self was inclined to consider the veins in these mines as of contempo- raneous origin with the rocks in which they are found. The heaves he hud ascertained to be in one and the same direction ^ and he con- ceived that, had they been caused by a mechanical force, they would be found in different directions. Mr. Hopkins believed there was no difficulty in solving Mr. Hen- wood's question, by reference to the operations of mechanical force, but several data were necessary at the outset. He was fully aware of the difficulty of miners recovering lost veins, and that it was highly desirable to have rules laid down for doing so. He entered into a dis- quisition upon the formation of veins in general, and first stated the theories that had been proposed to account for them. One was, that of the Cornish miners, as above stated. Another, that fissures in the rocks had taken place after their consolidation, which fissures had be- come filled subsequently with mineral matter: these fissures being either open cracks, or simply discontinuities of the strata. Mr. Hop- kins referred to his paper in the Transactions of the Cambridge Philo- sophical Society, where tliesubject vvas treated mathematically.* He considered the idea of the contemporaneous origin of veins as having no claim to the name of a theory, from it assigning no physical cause — it does not even call in the aid of electric agency. Suppose even ♦ Mr. Hopkins has subsequently given a view of his researches in Lond. and Edinb. Phil. Mag., vol. viii. p. 227- 126 British Association, that a small mass of matter were acted on and modified by fire, it might present veins within it ; but still no theory is assigned why these veins are so produced : here there is the action of fire, and con- sequently, after being acted on, the phaenomenon may be regarded as eflPected by igneous agency;— yet how can this explanation be ap- plied to sedimentary rocks r — to say, therefore, contemporaneous formation, is to use an unmeaning term. Suppose it may be ascri- bed to molecular attraction, still the cause is wanting; and although it might be of some avail in explaining the formation of globular masses, yet it is of no use in the present case, as we have to do with masses occurring in planes. In order to solve Mr. Henwood's ques- tion, we must know the angles which the veins make with each other, and also with the horizon, and the relative height of the strata on each side of the lines of dislocation. Mr. Hopkins considered that Corn- wall was an unfavourable countyfor explaining these phsenomena, as its rocks were generally unstratified ; and he would ))refer a county like Derbyshire, where the regularity of the stratification offered much fa- cility in finding the necessary data. — Mr. De la Beche considered Cornwall as perfectly suited for explaining these phaenomena on Mr. Hopkins's theory. In this county there exists a fossiliferous system, which has manifestly been upheaved by the granite, and is penetrated by the same granite veins which traverse the primary rocks. — Mr. Phillips said that we should not restrict the term contemporaneous, the real point urged by the Cornish miners being, that there was no displacement. Still we must seek for explanation in other di- stricts. In these, the mechanical theory must be at once acknowledged to be true, when we see the disturbance in fossiliferous rocks, in some cases even in an intersection of their organic remains. But this theory ought not only to explain the direct phaenomena, but must ac- count for the exceptions ; and in such cases, as in Cornwall, we must regard the structure of the rocks — their regular divisions and joints, which are independent of stratification, — veins may even occur in these divisions. In the north of England, the contents of veins are found to vary according to the containing rocks ; and he considers the circumstance of spar stuff occurring in the Cornish veins as not opposed to the idea of mechanical force, but as dependent upon elec- tric agency. — Mr. J. Taylor, jun. stated, that, in the course of his expe- rience in practical mining, he had observed certain conditions neces- sary for the profitable working of metals. In the oldest, or scar lime- stone, he had observed that the miner was not remunerated ; but in newer lead measures he had a better chance of success, as in grits and shales. The best chance was in altered rocks. In Cardiganshire he had observed a remarkable case in a slaty rock : where very schis- tose, the workings were poor ; but where the rock was diced, as the workmen call it, they were certain to be rich ; the strike of the altered rock being N. and S.,and that of the veins E. and W. He had seen remarkable proofs of the mechanical theory in North Carolina, espe- cially in the rich veins of iron ore of that country. — Mr. Sedgwick instanced the discussion now before the Section, as a proof of how much one branch of science was assisted by another: we here saw the application of Physics to Geology j he could record also the as- lieviews and Notices respecting New Booh. 127 distance rendered by Geology to Physics. This same Dolcoath mine, whose phaenomena of veins were so singuhir, was the one selected by Prof. Airy for determining the density of the earth. Mr. Sedgwick remarked, that fissures caused by crystallization were, in general, very small ; and that joints seldom coincided with rents ; — that in districts where granite approaches slate rocks, we may be certain of finding the richest metalliferous deposits. Practical miners had often whimsical ideas of the origin of metals. One of them had once gravely informed him that they were caused by peat^ and had shown wiiat he conceived to be a convincing proof, namely, their existence under a peat bog in his neighbourhood, and occurrence nowhere else in the same vicinity. — Sir W. R. Hamilton testified also to the impor- tance of new applications of mathematico-physical science. Not only would new views open, but even new methods of analysis would arise to assist the investigator. Dr. W. H. Crook made some observations on the unity of the Coal Deposits of England. The object of this communication was to show that the coal-fields of England and Wales were not distinct basins, but that the supposed basins were only portions which had been de- tached and elevated by the agency of syenitic and trap rocks, of a much larger deposit, spread over the greater part of the districts now covered by the new red sandstone. Of the vegetable origin of coal there is now no doubt : the only question unsettled is, did the plants supplying it grow on the spots where it is found, or were they trans- ported ? Dr. Crook inclined to the latter opinion, and conceives that this view may be extended to the coal of Belgium, of the north of France, and the north-west of Germany 3 the carboniferous beds of those countries having originated, in his opinion, in a drift of vege- table substances from countries lying to the east or E.S.E. of them ; and he also thought, that the extent and richness of the English coal- fields, especially in the Midland counties, arose in a considerable degree from the impediments ofl'ered to the transit of the drifted matter by the slate and other ancient formations of Wales and Cumberland. He considered, that the Charnwood Forest rocks had elevated the coal- field near it, and a similar elevation had taken place at Nuneaton. Mr. Greenough considered the idea of Dr. Crook as very probable; but observed, that the deepest of our coal basins had been found to be in South Wales. — Mr. Young, from Nova Scotia, stated, that large deposits of coals had been found in that country. — AtheneBum, No.b\7. XX. Reviews and Notices respecti?ig New Books, Electricity ; its Nature^ Operation, and Importance in the PhcEnomena of the Universe. By W. Leithead, Secretary to the London EleC' trical Society. London, 1837, V2mo. WE had occasion to notice lately an observation by a distinguished foreign contemporary, in which the writings of some of our coun- trymen in the department of electricity were treated as having contri- buted but little to its advancement. We have since, however, in addition to a Journal of Electricity, had the establishment of an 1 28 Reviews and Notices respecting New Booh, Electrical Society of London ; and the work now before us being' announced as the production of the Secretary of that Society, we oj)ened it with anxious expectation, to see how the national honour would be sustained by a personage placed in so conspicuous a station. Every one would of course not merely give credit to such a person for knowing something of what he was writing about, but expect from him some addition to our stock of knowledge ; public attention having been directed to the work by advertisements, fortified by the following eulogium, from no unfriendly hand, in the Atlas : " This treatise exhibits the first attempts to call attention to the extraordi- nary relations between the electrical conditions of the atmosphere and the human body " [most extraordinary indeed, as we shall find] ; " audit combines the rapid spirit of composition with the accuracy of cautious research, vigour and eloquence of expression with the strength of deep thinking." Of one of these subjects of panegyric, " the rapid spirit of composition," it might seem that only the author himself could well be cognisant ; but as it has been our fortune to ob- tain a glimpse of Mr. Leithead's method, we shall give our readers the benefit of it. They will no doubt recollect, as we happened to do while perusing Mr. Leithead, the excellent treatise on electricity by Dr. Roget in the Library of Useful Knowledge, making two numbers, or 64 pages, out of which we cannot help suspecting that the worthy Secretary has manufactured the first 120 pages of his book. At least the coincidence between the two is throughout nearly as remark- able as that which the following collation exhibits. Library of Useful Knowledge. Mr. Leithead. (§63) From what has already been P. 49. From what we have already said explained of the general laws of electri- respecting the general laws of electri- city, the mode in which these machines city, the modus operandi of these ma- act will readily be understood. The chines will be readily understood. By friction of the cushion against the friction between the cushion and the glass cylinder produces a transfer of glass a transfer of the electric electric fluid from the' former to the fluid takes place from the former to the latter; that is, the Cushion becoming latter; the cushion becoming negatively, and the glass positively, elec- negatively, the glass positively, elec- tiifled. The fluid wliich thus adheres trifled. The fluid which adheres to the glass, is carried round by the to the glass, is carried round by the revolution of the cylinder; and its revolution of the cylinder; its escape is at first prevented by the escape being at first prevented by the silk flap, &c. silk flaps, &c. To exemplify further his modus operandi (a favourite expression with the Secretary), we give two other sections from Dr. Roget, in- terlining them with a few alterations of phrase here and there, which if substituted for what stands under them in the text, will give us precisely the product of Mr. Leithead's " rapid spirit of composition, accuracy of cautious research, vigour and eloquence," &c. &c. &c. Library of Useful Knowledge. Leithead, ip. 61. electricity along " (§. 86.) The passage of (the electric fluid through) a perfect con- It when the ductor is unattended with light. (Light) appears only (where there lievieivs and Koikes lespectivg New Books. 129 course of the electric fluid is impeded by are obstacles in its path by the interposition of) imperfect conductors ; of its passage, under such circumstances, and such is the velocity ( with which it is transmitted, ) that the light is visible (sparks appear to take place) at the very same instant along the This may be illustrated by pasting a row whole line of its course. (Thus if a row of small fragments) of tin- discs of a small size (fig. 18.) foil (be pasted) on a piece of glass (fig. 19.)" [Here the figure is copied, and so are many of the others, only re- versed, or slightly altered.] Library of Useful Knowledge. Leithead, p. 28. Now it must be remembered these cases " (§ 105) (It should be recollected) that in all (the changes we have thus traced as the eflfects of induction, there has been) no transfer of the electric fluid has taken place between (electricity) (from either of ) the bodies (to the other); which is the experiment in which (as was suflficiently) proved, (indeed,) by (their taking place equally the glass plate is if ) (a plate of glass be) interposed. Another proof is afforded by the circumstance that the mere removal of the bodies to a distance from each will its own (one an)other, (is sufficient to) restore each of them to (their) original in as positive a state state. The globe remains (as positively electrified) as before ; the resumes state there cylinder (returns to) its (condition) of perfect neutrality ; (nothing) no loss, no gain has been (lost, ) (and nothing gained) on either side. The experi- over and over again, the phaenomena ment may be repeated (as often as we please,) (without any variation will not vary. the eflfects would be difi'erent in the phaenomena). But (this would not be the case) if the cylinder was (were) divided in the middle, and one or both of the parts were remo- ved separately, while they still remained under the influence of the globe." The above are at any rate very amusing specimens of the art of ringing the changes upon words and sentences, sometimes at the ex- pense of style and grammar ; but how insufficient for the purpose of disguising wholesale piracy will be quite evident to any who may be disposed to follow up the comparison from page to page throughout the first part of the work, and to admire the gravity with which our Secretary struts about in his borrowed feathers. With the ** accu- racy of cautious research," he discovers the two above-mentioned sixpenny Nnmbers in Paternoster llow, and with " the strength of Phil. Mag. S. 3. Vol. 12. No. 71. SuppL Jan. 1838. S 130 Intelligence and Miscellaneous Articles. deep thinking" he makes with his pen the erasures and interlinea- tions which we have exhibited above. The first 120 pages being made up in this way, whence the other portion of the book is derived we have not taken the trouble to ascer- tain. Before we turn to the second part, we will just quote a passage from the Preface : " That it has no pretensions to the title of a scien- tific treatiseis self-evident — (who will doubt this ?) — the author's ob- ject in the first part of the work, being simply so to explain the se- veral varieties of electrical action as to enable the non-scientific reader to understand the modus operandi (!) of the electric fluid in producing the different phsenomena which are treated of in the se- cond part." Some may be rather curious to know now of what the second part is made up, after the statement of " one so humble in the ranks of science" ; and they will no doubt be astonished to learn that it treats of nothing less than cholera morbus, phsenomenaof disease, inflammation, fever ; the modus operandi of the electric fluid in im- parting their forms to vegetables and animals ! and that it is neither more nor less than an electrical dream of Mr. Leithead's fancy. And all this for non-scientific readers, in a treatise on electricity. The cholera morbus is made to depend on aurora borealis, shooting stars, &c, ; and the vital principle to be probably identical with the elec- tric fluid. Mr. Leithead, moreover, sees " no reason why water should not be composed of hydrogen and oxygen in the planet Mercury, as is the case on our earth," for he conceives " that the degree of force with which an atom retains its electro-polarity on any of the heavenly bodies, will bear some exact ratio to their distance from the sun." — p. 397. We have nothing further to say of this notable production ex- cepting that its price is eight shillings, whilst the two numbers of the Library of Useful Knowledge are sold for sixpence each. XXI. Intelligence and Miscellaneous Articles, ABSORPTION OF WATER BY EFFLORESCENT SALTS. MR. HUGH WATSON in a paper read before the Philosophical Society of Manchester, observes, " Hitherto I have considered those salts which are usually described as efflorescent salts, to be such as would effloresce whenever they were left exposed to an atmosphere not saturated with vapour, but capable of evaporating water ; and I believe that the same idea is generally entertained on the subject. Now the result of my investigation furnishes the proof that such an idea is not a correct one ; it shows that the crystallized sulphate and carbonate of soda, which are generally considered as very efflo- rescent salts, may be left exposed to the atmosphere for any length of time without efflorescing in the least, or losing a single particle of water of crystallization, though that atmosphere be dry and capable of evaporating water, so long as its evaporating poxuer isjiot allowed to extend beyond a certain point ; this point differs for each salt. In order to find how much water pure anhydrous carbonate of soda is capable of absorbing, 1, on the 20th October, 1835, put 474< grains = 1 atom (supposing the atom of soda to be 28, and that of Intelligence and Miscellaneous Af tides, ISl the carbonic acid to be 194) prepared by calcining the bicarbo-. nate into a watch-glass of known weight, and left it exposed to the atmospliere in a room in which no fire was kept. By frequently weighing the glass and its contents 1 found the gain of weight to be as follows : Oct. 21 22 23 24 25 26 Weight gained. 3-3 grains. Oct. . 6 1 . 91 ,. 11-8 . 13'8 ,. 161 Weight gained. 27 .... 18-6 grains. 28 .... 211 29 .... 23-6 30 .... 26-6 31 .... 28-6 The salt having concreted into a rather hard mass was now broken up, so that it might the more readily acquire more moisture. Weight gained. Weight gained. Nov. 1 .... 31*6 grains. Nov. 3 .... 386 grains. 2 34-1 4 40-8 The salt was now removed from the watch-glass, crushed and spread over the surface of a dinner plate, so that the process might be sooner finished. Weight gained. Weight gained. Nov. 6 .... .56*1 grains. Nov. 16 78*6 grains. 11 .... 77-6 21 .... 78-6 14 .... 78-6 1 left it exposed to the atmosphere till the 4th December, when I found it to be of the same weight as on the 21st November. It was therefore evident that no more water could be absorbed. Now the 78*6 grains of water absorbed are only 1 '4 grain short of being equivalent to ten atoms *, and it is probable that a waste of that quantity of salt may have been made in the numerous weigh- ings. If this be granted, the author says he is right in concluding that the anhydrous carbonate acquires water until it is of the same constitution as the crystallized carbonate, if exposed to such an atmosphere as he made use of, one in which the temperature ranged from 53° to 43°, and whose vapour point is not more than 7° below the temperature nor less than 5°. The vapour point was ascertained by the aid of an hygrometer on tiie principle of Leslie's, and de- scribed by the author at the meeting of the British Association at Edinburgh. On the 20th of October, 100 grains of crystals of carbonate of soda were exposed in the same room as that above alluded to; by one day's exposure 2^ grains were lost, and no further loss occurred although the expo.sure was continued till the 4th of December. Mr. Watson therefore concludes that the water was merely adherent, and not combined. In a room in which a moderate fire was regularly kept Mr.Watson exposed 20 grains each of crystals of sulphate of soda, of crystals of [* Onlv 04 gr. short of 10 atoms, if the usual equivalents are adopted, 47-4: 78-6: ;54 . 89-6.— Edit.] S2 132 Intelligence and Miscellaneous Articles* carbonate of soda, and of anhydrous sulphate of soda; the first from the 3()th of October to the -l-th of December, and the two last from the 31st of October to the 4 th of December. The crystals of sul- phate of soda began in one day to effloresce, and on the 9th of De- cember they had lost 9| grains; and Mr. Watson concludes that if the exposure had been continued they would have become anhy- drous. The anhydrous sulphate gained no weight. On the 1st of November, the crystals of carbonate of soda were found neither to have lost weight nor to have effloresced in the slightest degree ; on the 5th, some of the outside crystals were slightly effloresced, which appeared to be in consequence of the lowness of the vapour point on the 2nd (11° below the temperature), and also on the 4th (lO'* below the temperature); on the 11th, these crystals were no more effloresced than they were on the 5th ; by the 10th December, how, ever, efflorescence was considerably more apparent, though even then it had not made a great advance ; in the interval between the 11th of November and the ^th of December, the vapour point had several times been 10° and IP below the temperature, which was undoubtedly the cause of this further efflorescence. The conclusion drawn by Mr. Watson from the above and other similar experiments is, that the crystals of carbonate of soda begin to effloresce at the temperature of 58°, when the vapour point is at 48°, and that the crystals of sulphate of soda begin to effloresce at the temperature of 58°, when the vapour point is at 49°; and there- fore, that the carbonate may be left exposed to the atmosphere at the temperature of 58° when the vapour point is not lower than 49°, and the sulphate when the vapour point is not lower than 50*', with- out any of their water of crystallization being lost ; and since the atmosphere in those states of dryness is capable of evaporating un- combined water, we have beautiful means afforded of providing ourselves with the salts in question free from any water not belong- ing to the constitution of the crystals, but at the same time, with all that does belong to it. As the crystals of sulphate of soda only begin to effloresce at the temperature of 58° when the vapour point is 49°, Mr. Watson considers that when the vapour point is only at 50° then the affinity of space for vapour is just equal to the affinity of this salt for its water of crystallization. The ordinary phosphate of soda appears to possess the same efflorescing property as the carbonate. — DETECTION OF COMMON SALT IN CHLORIDE OF POTASSIUM. Mr. Watson in the paper from which the above extract is made, ob- serves that it is sometimes a desideratum to ascertain if and to what amount muriate of potash [chloride of potassium] (an article much used in the manufacture of alum) is adulterated with common salt. The means, he observes, which would hitherto be used to accomplish that object are tedious. Jf, however, a solution of a sample of the kind in question be treated with sulphate of ammonia till all the chloride is converted into sulphate, and the resulting mixture be evaporated to dryness, and calcined till all the ammoniacal salt is dissipated, the residue will be the anhydrous sulphate of the alkali or alkalis of the sample; by placing this under an exhausted re- Intelligence and Miscellaneous Articles, 133 teiver along with a vessel of water, we shall be able to ascertain whether it is pure sulphate of potash or mixed with sulphate of soda; if it be the former it will gain no permanent weight however long the experiment may be continued ; but if there be any of the latter present, it will gain weight till that portion becomes of the same constitution as it is of when it exists in the crystallized state. I NEW ACETATE OF LEAD. M. Payen produced to the Academy of Sciences a regularly cry- stallized specimen of a new acetate of lead. It is composed of three atoms of neutral acetate and one atom of trisacetate ; its for- mula is represented by 3 PbO, C« H« 0=»+ 3 (PbO, C« H^ O^). It is distinguished from the neutral and trisacetate by its crystalliza- tion in hexagonal plates, which form slowly, by exposing the solu- tion, in radiating mamellated crystals; it crystallizes very abun- dantly so as to become almost a mass on cooling, whilst the trisace- tate crystallizes with difficulty. Its solubility in water and of alco- hol of various strengths, both cold and hot, is much greater than that of the two other acetates ; thus at 65° Fahr. water dissolves about four times as much of it as of the neutral acetate and six times as much as of the trisacetate. It has an alkaline reaction ; it is more stable than the first acetate and less so than the second. A saturated aqueous solution dissolves either of the other acetates, and acquires by so doing the consistence of a syrup, and thus re- tards or prevents all crystallization. An equal volume of anhy- drous alcohol does not decompose this solution, whereas it causes the other acetates to appear in their respective solutions. When heated it suffers igneous fusion only, while the neutral acetate un- dergoes two successive fusions and the trisacetate does not fuse at all. It does not lose any of its acid in a dry vacuum, whereas the neutral acetate loses a portion of it on cooling. Carbonic acid de- composes an atom of the trisacetate of lead, and converts it entirely into neutral acetate. This new acetate can, on the contrary, dis- solve hydrated or anhydrous oxide of lead and become complete trisacetate. By the addition of ammonia, according to the propor- tion and temperature, the new acetate yields either trisacetate, or anhydrous protoxide of lead, or crystallized hydrate. This acetate is prepared by dissolving three atoms of neutral ace- tate in a solution of one atom of trisacetate; after due evaporation the solution is to be allowed to crystallize, and this occurs in three or four days after the solution has become cool ; the crystals are to be drained, pressed in blotting paper, and dried in vacuo 3 a syrupy solution remains. M. Payen observes that the existence of this new acetate explains why several authors have stated that the subacetate of lead is more soluble than the acetate, while others have shown the contrary : this has happened because the former have observed the solubility of the new acetate or of its mixtures, while others have operated on the trisacetate. It also appears why the neutral acetate effloresces, and by losing a portion of its acid in the air acquires an alkaline reaction, then .1 34- Intelligence and Miscellaneous Articles, combining gradually with carbonic acid is gradually converted into this new subsalt, and then into carbonate. This alteration, the first step of which occurs even in air deprived of its carbonic acid and in vacuo, explains the difficulty which all chemists have experienced in obtaining a solution of neutral acetate which is not precipitated by carbonic acid. Lastly, it is owing to the formation of the subsalt by the spontaneous disengagement of the acid, which occurs in the manufactories of acetate of lead, that the mother waters are rendered uncrystallizable, and this would occasion great loss, if an excess of acetic acid was not employed. It is evident that the disappear- ance of only one part of acid renders a solution of about 20 parts of acetate syrupy. — V Institute Nov. 1837. [As the symbols merely and not the analysis of this new subace- tate appear in the above extract, the exact composition of the salt is not very easily arrived at. I suspect that it is a compound of 4< equivalents of acid +5 equivalents of oxide, which are equal to 3 equivalents of acetate and 1 eq. of diacetate of lead. — R.P.] SULPHURET OF AZOTE. M. Soubeiran obtains sulphuret of azote by the action of ammo- nia upon chloride of sulphur; the dried ammoniacal gas is passed into a large receiver, in which there is placed a capsule containing a small quantity of chloride of sulphur, which is renewed when the action is over ; a dirty green flocky matter is formed, which is ex- posed for 24 hours to an atmosphere of ammonia; the product of this operation is a mixture of hydrochlorate of ammonia and sul- phuret of azote ; it is treated with water, which dissolves the ammo- niacal salt only. The success of this operation requires several precautions ; the chloride of sulphur must be saturated with chlorine ; the tempera- ture must be prevented from rising by the action of the ammonia upon the chloride of sulphur; on this account a large receiver should be used, and small quantities of chloride of sulphur must be em- ployed at a time ; the ammonia must always be in great excess ; the mixture of sulphuret of azote and hydrochlorate of ammonia should be quickly washed ; the sulphuret of azote must be dried, first by pressure between folds of blotting-paper and afterwards in vacuo. The following are the principal properties of sulphuret of azote; it has a lemon yellow colour ; is inodorous; at first it is tasteless, but it soon imparts a very distinct acrid taste. It detonates vio- lently by percussion, or by the sudden application of heat. If it be mixed with some inert body it decomposes quietly, at about 284° Fahr.^ into sulphur and azote. It is slightly soluble in water ; but it is gradually converted by heat into hyposulphate of ammonia; it is more soluble in alcohol and tether than in water. When the aether is very pure and dry, after its evaporation, it leaves crystallized sul- phuret o^ azote. The alkalis convert it quickly into ammonia and hyposulphate ; with the acids it yields ammonia, sulphur, and sul- phurous acid. Sulphuret of azote is formed of two atoms of azote (two volumes) and three atoms of sul})hur. It corresponds, in the series of the sulphurets, to the acid of the nitrates in the series of Intelligence and Miscellaneous Articles. 135 oxygenated bodies; it is nitrous acid, in which oxygen is replaced by sulphur. Sulphuret of azote possesses the general character of the amides ; by combining with water it changes into ammonia and an acid. — L'Institut,'biov.}831. XANTHOPHYLLE, — THE COLOURING MATTER OF LEAVES IN AinUMN. Berzelius immersed the lemon-yellow autumnal leaves of ihePi/rns communis, immediately after they were gathered, in alcohol of sp. gr. 0*833, and they remained in it for 48 hours. The alcohol be- came of a yellow colour, but the leaves were slill yellow, though paler than at first. The alcohol was decanted, and the bottle was kept for some time inverted : the leaves, whenever they were acted upon by the air, became brown, whereas the parts of the leaves in contact with the bottle retained their yellow colour. Alcohol was repeatedly poured upon the leaves, and was each time rendered yellow ; and lastly, the leaves were boiled in alcohol : it still ac- quired a slight yellow tint, but became gelatinous on cooling. The various alcoholic solutions were mixed and distilled to l-8th ; there was then deposited agranular and somewhat crystalline substance; after this was separated, the distillation was continued, until there remained only the water of the vegetation of the leaves. On this yellowish brown liquor there floated a soft, yellow, greasy sub- stance, which appeared identical with the grains containing the yel- low colouring matter of the leaves. These grains do not appear when examined by the microscope to possess any crystalline struc- ture; when rubbed by the hnger they become a yellow unctuous greasy matter; this is mixed with a small quantity of fat oil, which could not be separated with any certainty, with another greasy sub- stance also ; the greater portion of tiie former may be separated by digestion with potash, which saponifies the oil and dissolves but little of the yellow grease ; the yellow fat acids are precipitated from the alkaline solution by hydrochloric acid ; and by redissolvir.g them in water containing in each ounce about five or six drops of ammonia, and again precipitating, they may be obtained colourless. In order to deprive it of the solid fatty matter, it must be treated with cold alcohol, in which it is not soluble. It was not possible to separate these two fatty matters. As it was procured it was a yel- low unctuous fat, readily fusible and liquefying at 108°Fahr. j it then concretes, becomes transparent and yellowish brown ; it cannot be volatilized without decomposition, and when distilled it yields a brownish fat, which is slightly soluble in alcohol, and leaves a residue of carbon. It is insoluble in water, but if when melted, hot water be poured upon it, it becomes transparent, swells slightly, assumes a paler yellow colour, as if water had chemically combined with it. When sprinkled with water and exposed for a long time to the air and light it becomes colourless, and a fatty mutter is formed which is with difficulty soluble in alcohol, and when dissolved in it by heat it precipitates light white flocks as the solution cools. The yellow fat is also but slightly soluble in alcohol. It does not sensibly become colourless in the solution, in the same time that it 136 Intelligence and Miscellaneous Articles, bleaches with water. The alcoholic solution is decomposed by wa- ter; it then has a pale yellow milky appearance, which it is difficult to render clear, and it retains this appearance after the evaporation of the alcohol. By spontaneous evaporation it separates from the alcohol in the state of a granular crystalline mass, ^ther dissolves it in large quantity, and it remains, after the evaporation, transpa- rent and of a yellow colour. When mixed with sulphuric acid it becomes brown; a small quantity, altered in properties, is dissolved; the solution is yellowish brown, and is precipitated by water of greyish white. By caustic potash it is but very slightly dissolved, and the solution when exposed to air and light becomes colourless; acids throw down pale yellow flocks from the potash, which when properly washed do not redden litmus. It is but little, if at all so- luble in carbonate of potash, and is insoluble in caustic ammonia, to which, however, it imparts a yellow colour. This yellow colour- ing matter is then a peculiar fatty matter, intermediate as to the fat oils and the resins, which may be bleached and retain its property of dissolving in alcohol with difficulty. It may be called Xantho- phylle (from lavQos^ yellow, and ^vWov, foliage). Berzelius thinks that there is every reason to suppose, that during the disappearance of the green colour of leaves, and its conversion to a yellow colour, this is derived from the green, by means of some change in the or- ganization of the leaf, effected by cold, which modifies the organic action ; he tried in vain to reproduce the green colour from the yellow, nor could he convert the green to yellow. There is nothing in common between the brown and the yellow colour of the foliage; the former is produced by an extractive principle which is at first colourless, and which after the disorganization of the epidermis of the foliage, becomes brown by the action of oxygen ; it then com- municates to the fibre of the skeleton of the foliage a brown colour, which cannot be removed even by digestion in caustic potash, nor destroyed by long treatment with sulphuretted hydrogen. — Journal de Pharmacies July 1837. DETECTION OF METALLIC CHLORIDES IN BROMIDES AND IODIDES. BY M. HENRY ROSE. It is very easy to discover small quantities of soluble bromides and iodides in great quantities of metallic chlorides ; but on the contrary, it is very difficult to discover minute quantities of metallic chlorides in large quantities of metallic bromides and iodides. After many experiments, M. Rose succeeded in discovering very small quantities of chloride in bromide of sodium; when bromide of sodium is mixed with excess of chromate of potash, and the mixture is distilled with concentrated sulphuric acid, pure bromine only is given out, which dissolves in excess of ammonia, forming a solu- tion which is perfectly colourless. If chloride of sodium be treated in the same manner, there is obtained chromate of chloride of chro- mium, the colour of which very much resembles that of pure bro- mine, but which, when dissolved in ammonia, forms a solution of a deep yellow colour, in which the usual tests easily discover the pre- sence of chromic acid. Intelligence and Miscellaneous Articles. 1 37 In order to detect a chloride in a metallic bromide, it must be mixed and powdered with bichromate of potash ; this mixture is to be put into a small tubulated retort, to which a receiver containing a sufficient quantity of solution of ammonia is adapted by a cork j there is then poured upon the mixture an excess of fuming [con- centrated ?j sulphuric acid, and the retort is to be heated. In employing only 0*012 of a gramme of chloride of sodium mixed with 0*640 of a gramme of the bromide, indications of chro- mic acid were obtained in the ammonia, but in this case it was not by the colour that it was recognised ; it was detected by evapo- rating the ammoniacal solution to dryness and exposing the residue with a phosphate to the flame of the blow-pipe upon charcoal; heated to redness. But if greater quantities of a mixture contain- ing a smaller proportion of the chloride be employed, a yellowish ammoniacal solution may be obtained ; this was done with a mixture of 0053 gramme of the chloride with 0580 gr. of the bromide. M. Rose endeavoured, but without success, to determine the quantity of the chlorine by this process. If iodide of potassium be mixed with excess of chromate of potash, and heated with sulphuric acid, iodine only is disenjraged ; if a mixture of iodide of potassium with chloride of potassium or sodium be treated in the same manner, no chromate of chloride of chromium is obtained, but chlorine is first evolved, and afterwards vapour of iodine, so that no chloride of iodine is formed. It is only when the proportion of metallic chlo- ride is greatly in excess, that chromate of chloride of chromium is procured ; 12 parts of iodide of potassium with 60 parts of the chlo- ride impart a slight yellow colour to the ammoniacal solution ; but 12 parts of iodide with 20 or .'^0 of chloride, did not yield a trace of chromium to the ammoniacal solution. On account of this sin- gular property ii is not possible to discover the presence of the chloride in the iodide of potassium, by the same process as that by which it is detected in the bromide. The best method of detecting small quantities of metallic chloride in the iodide of potassium is that proposed by M. Gay Lussac, founded upon the very slight so- lubility of iodide of silver in ammonia. Add a solution of nitrate of silver to a solution of the salt, until no further precipitation takes place, then add ammonia in excess. If after agitation and filtering, only opalescence occurs in the liquor on supersaturating it with nitric acid, it is a proof that the iodide of potassium contains no chloride or but a trace ; this last salt would be discovered by the precipitation of chloride of silver when supersaturated by nitric acid. — Journal de Pharmacies October 1837. ON THE EMPLOYMENT OF METALLIC SULPHURETS IN ANALYSTS. BY MONS. E. F. ANTHON- It is well known that certain oxides possess the property of pre- cipitating others from their solutions, by combining with the acid of the dissolved oxide ; and this process has been adopted for the separation of certain metallic oxides. Phil. Mag, S. 3. Vol. 12. No. 71. SuppL Jan. 1838. T 138 hitellisence and Miscellaneous Articles. 'to Metallic sulphurets, prepared in the usual way, may be employed in the same way as the oxides, for precipitating oxides from their solutions 'j the latter are then converted into sulphurets, whilst the raetal of the sulphuret continues in the state of oxide with the acid, previously united with the metal precipitated ; this action of the sulphurets frequently possesses advantages in chemical analysis. The results obtained by employing eight metallic sulphurets will be stated j they were prepared either by precipitation with sulphu- retted hydrogen or an alkaline hydrosulphate. In operating on the solution of a salt by a sulphuret, the sulphuret was always used in excess, and the mixture was exposed to a boiling heat for about a quarter of an hour. Sulphuret o/'Leat;? precipitates nitrate of silver, sesquichloride of iron, nitrate of copper j it does not precipitate nitrate of cobalt, ni- trate of cadmium, nitrate of manganese, sulphate of nickel. Sulphuret of Cobalt precipitates acetate of lead, sesquichloride of iron, sulphate of cadmium, sulphate of copper, nitrate of nickel, nitrate of silver; it does not precipitate sulphate of manganese. Sulphuret of Iron precipitates nitrate of lead, sulphate of cad- mium, sulphate of copper, nitrate of silver ; it does not precipitate nitrate of cobalt, sulphate of manganese, nitrate of nickel. Sulphuret of Cadmium precipitates nitrate of lead, sulphate of copper, nitrate of silver; it does not precipitate nitrate of cobalt, sesquichloride of iron, sulphate of manganese, nitrate of nickel. Sulphuret of Manganese precipitates acetate of lead, nitrate of cobalt, sesquichloride of iron, sulphate of cadmium, sulphate of cop- per, nitrate of nickel, nitrate of silver. Sulphuret of Copper precipitates nitrate of silver ; it does not pre- cipitate acetate of lead, nitrate of cobalt, sesquichloride of iron, sulphate of cadmium, sulphate of manganese, nitrate of nickel. Sulphuret of Nickel precipitates acetate of lead, sesquichloride of iron, sulphate of cadmium, sulphate of copper, sulphate of silver; it does not precipitate nitrate of cobalt, sulphate of manganese. Sulphuret of Silver does not precipitate acetate of lead, nitrate of cobalt, sesquichloride of iron, sulphate of cadmium, sulphate of copper, sulphate of manganese, nitrate of nickel. It will be observed on examination that sulphuret of manganese decomposes all the solutions of raetaUic oxides tried, while the sul- phuret of silver did not decompose any one whatever j it results from these facts that if silver has the strongest and manganese the weakest affinity for sulphur, all the other metals are intermediate as to these, and arranged according to their degrees of affinity for sulpliur; they stand thus: silver, copper, lead, cadmium, iron, nickel, cobalt, manganese. The metals are here so arranged that any one of them in state of sulphuret does not act upon a solution of the metals following: thus for example, the sulphuret of nickel precipitates the salts of silver, copper, lead, cadmium, and iron, but effects no change in those of cobalt and manganese. There is only one exception, it is that the sulphuret of iron pre- Intelligence and Miscellaneous Articlesl 139 't> cipitates the nitrate of lead, whilst the sesquichloride and pernitrate of iron are only partially precipitated by the sulphuret of lead, — Journal de Pharmacies October 1837. ON THE FERMENTATION OF SUGAR OF MILK. BY M. HESS. It has generally been admitted by chemists as an indisputable fact, that sugar or milk is incapable of fermentation. Pallas endea- voured, but in vain, in his collection of historical facts respecting the people of Mogol, (St. Petersburgh, 1776, vol. i. p. 33), to con- trovert this generally received opinion, by objecting that the people of Asia prepared an intoxicating liquor from milk; although this fact was known to many persons, and has often been quoted re- specting milk, the idea has nevertheless remained, that sugar of milk is not susceptible of the alcoholic fermentation, and it has been proposed to expunge it from the list of sugars, and to give the name of lactin. In order to elucidate this subject by some experiments, M. Hess fermented cow's milk in wooden vessels ; the fermentation occurred spontaneously and without any addition ; it is necessary only that the vessels should be sufficiently deep and exposed to a sufficiently high temperature ; it is of no consequence whether the milk be pre- viously skimmed or not. The fermentation continues for a long period ; it is accompanied with a disengagement of gas, perceptible even by the ear. The gas collected was examined by solution of potash, which absorbed it within y^ part, which could be nothing but atmospheric air ; the fermented liquor was passed through a flannel, to separate the ferment, and afterwards distilled. The product of the distillation was acid ; it was saturated with carbonate of lime, and several times redistilled, taking care to receive each time only one-fourth of the liquid. The liquor thus obtained was mixed with excess of dry carbonate of potash, which combined with the water, and an alcoholic liquor floated on the saline one ; it was separated by repeated distillations from the salts which it contained; then, in order to have it pure, it was rectified from lime ; it always possessed a peculiar odour. By analysing O'^S of this liquid there were obtained 0*827 of carbonic acid, and 0*561 of water_, which gives for 100 parts : Carbon 47"64 Hydrogen 1 2*96 Oxygen 39*4'0 100* and as 4?7'64? of carbon indicate 90*46 of alcohol, which are equal to Carbon l-7'64 Hydrogen 11*66 Oxygen 31*16 90-46 there remain 13 of hydrogen, which indicate 1181 of water, from which there results an excess of 2*27 in 100. As M. Hess performed this analysis with care, and believed he was sufficiently guarded from the usual source of error, that is, of hygrometric moisture, he pre- T2 140 Intelligence and Miscellaneous Articles. sumed that there was present in the hquor some combination con- taining more hydrogen than alcohol does; and it is proved by the experiments of Doebereiner that ammonia is formed during fermen- tation. A solution of chloride of platina produced so abundant a precipitate in the liquor of amraonio-chloride of platina, that the author almost suspected an accidental error. The experiment was then repeated with a certain quantity of alcohol recently prepared from milk ; the precipitate was collected on a filter, dried and then heated to redness in a glass tube. The large quantity of muriate of ammonia obtained, left no doubt on the subject in question. M. Hess also determined that the peculiar odour was derived from an admixture of ammonia. Then in order to obtain pure alcohol, he first separated the water by lime and then distilled it with a salt wa- ter bath, at a very low temperature, with a ^tivf drops of sulphuric acid. The liquor obtained had however a weak aethereal odour j 0*513 gave 0*993 of carbonic acid and 0 596 of water, which give for 100 parts: Carbon .. 53*4'3 but alcohol contains 52*66 Hydrogen 12-90 .. .. 1290 Oxygen. . 33-67 . . . . S**^^ 100- 100* The aethereal odour sufficiently explains the cause of the slight ex- cess of carbon, and it appears, in fact, that the alcohol obtained is identical with common alcohol, but in order to be quite certain of this, M. Hess mixed it with an equal weight of sulphuric acid, and he obtained by distilling the mixture common sulphuric aether. As all kinds of milk are susceptible of fermentation, and as no other kind of sugar but sugar of milk has been discovered in them, these facts prove that it must be fermentable. The author is of opinion that two facts have especially contributed to lead observers into error; first, it is quite possible that the usual ferment (yest) is not sufficiently powerful to decompose sugar of milk, which requires for its decomposition the action of its natural ferment (caseum); se- condly, the extreme slowness of the fermentation. — Journal dePhar" maciet October 1837. FORMATION OF NITRE IN EXTRACT OF QUASSIA. BY M.PLANCHE. The ashes of quassia are slightly alkaline and cold water dissolves about 25 per cent, of them, composed of potash, lime, carbonate of potash, carbonate of lime, chloride of sodium, nitrate of potash, and traces of sulphate. The insoluble residue yielded a little sulphate of potash and of lime to boiling water ; the remainder consisted principally of carbonate and sulphate of lime. There are few vege- table ashes which contain so small a quantity of alkali, and the ex- istence of nitre in a product which has been subjected to a red heat is also remarkable. Not only is nitre contained in the ashes of quassia, but it exists in the extract, and the quantity increases by exposing it to the ac- tion of air and moisture. An ounce of extract of quassia (A) recently prepared, and of a consistence fit for pills was put into an earthen Intelligence and Miscellaneous Articles, 141 vessel, capable of holding four ounces ; it was furnished with a cover j it was kept in a place which was perfectly dry at all times. An equal quantity of the same extract (B) was put into a similar vessel covered merely with linen j this vessel was placed on a stand, at about four feet above ihe ground in a place used occasionally for distillation, and in which large quantities of water were evaporated, so that the air contained more or less moisture; in the same place and by the side of the extract of quassia, and in a similar vessel also covered with linen, an ounce of extract of gentian was placed (C), which is well known to contain no nitre. All the vessels thus placed were kept so for a whole year, at the expiration of which the three extracts were examined. The extract (A) was rather dried and had lost ^7 grains, Treated repeatedly for half an hour, with boiling alcohol of sp. gr. 837, it yielded 8 grains of nitrate of potash. The extract (B) was much softened and had increased 90 grains in weiglit, it was heated in a salt water bath, in order to restore it as nearly as possible to its original consistence, it was then treated like the foregoing. It yielded 10^ grains of nitrate of potash. Lastly, the extract (C), that of gentian, had increased 38 grains in weight. Submitted to the same treatment as the preceding, it did not yield an atom of nitre. Thus in the extract (B,) which was exposed to moist air, the increase of nitrate of potash was 2| grains, in the space of a year, whilst the extract (C), which had been placed in the same circumstances, and in which there exists no azotized matter like that of quassia, no por- tion of nitre was formed. M. Planche concludes that after these re- sults it is difficult not to attribute the newly-formed nitre in the ex- tract of quassia to the azotized matter which it contains. — Journal de Pharmacies November 1837. METHOD OF DISSOLVING IRIDIUM. BY M. FELLENBERG. M. Fellenberg remarks that by Wcshler's method of separating iridium there is obtained a double alkaline chloride of iridium, whereas by his process, which is as follows, a simple chloride is ob- tained which is very soluble in water- This process is founded on the fact that chlorine converts the greater number of metallic sul- phurets into corresponding chlorides. Iridium, separated from the ore of platina, containing osmium or not, is to be reduced to the finest powder in an agate mortar; upon this, the success of the process mainly depends. This powder is then to be mixed with three times its weight of flowers of sulphur, six times its weight of carbonate of potash or dry carbonate of soda, then heated in a well closed porcelain crucible, and kept in a strong red heat till no vapour of sulphur or of sulphurous acid is percep- tible. When the crucible is cold, the mass, which is of a black-brown colour, is reduced to powder, and washed with boiling water till it ceases to produce any effect upon a solution of lead. The sulphuret of iridium is easily separated from the liquor by simple decantation ; it is then to be thoroughly dried and reduced to a fine powder. This is to be placed in a tube with a bulb, which is to be con- H2 Intelligence and Miscellaneous Articles, nected with an apparatus, evolving dry chlorine gas : the apparatus is first filled with this gas, the sulphuret of iridium is heated in the bulb by a double-wicked spirit lamp. By the gradual action of the heat, sulphur and its chloride are volatilized ; the mass which has hitherto been black, crystalline and brilliant, becomes brown and afterwards yellowish red. When no more chloride of sulphur ap- pears, the heat is to be raised so as to render the bulb strongly red hot, chlorine is again to be passed in until no further change appears. The experiment is then finished ; the lamp is to be removed, and the apparatus is to be allowed to cool, full of chlorine. The chlo- ride of iridium then forms an orange-coloured mass, which imme- diately dissolves, without residue, in cold distilled water ; the solution is transparent and of a deep orange-red colour. This is the chloride of iridium, it has sometimes a purplish tint, and it then possibly contains some sesquichloride. If any residue remain it is either metallic iridium or sand, or white brilliant spangles of osmo-iridium, which has escaped all the previous reactions ; they may easily be separated by washing. If the iridium contains osmium the same process is employed, but the chlorine is used moist ; when the chloride of sulphur has dis- tilled, white thick vapours appear, which when sublimed into a cool tube, give a crystalline mass of fine white osmic acid, while all the iridium remains in the bulb. If the chlorine were dry, chloride of osmium would sublime, which condenses with greater difficulty than oxide of osmium, and is easily carried away by excess of chlo- rine. But by the aid of moist chlorine, the osmic acid is obtained isolated, and it may be conveniently collected in a long and large tube, drawn out and kept cool at the end, while all the chloride of iridium remains iu the bulb ; by this process the two metals may be separated. M. Fellenberg learnt by chance that moist chlorine favours the separation of osmium and iridium ; he observed, that in a parallel experiment as soon as the tube which contained the chloride of cal- cium for drying the gas, was moist, and that all the chloride of sul- phur had distilled, white vapours of oxide of osmium were formed, which were received in a long cold glass tube ; these were recog- nized by their crystalline form, their action upon sulphurous acid, and on tinctura of galls. With perfectly dry chlorine, no trace of oxide of osmium is ob- tained, but only chloride which condenses in the state of a reddish brown crystalline powder, the greater part of which is carried off and may be collected in a bottle containing distilled water. — Jour- nal de Fharrnacie, November 1837. ON LACTIC ACID IN SOUR-CROUT. BY M. LIEBIG. Sour-crout contains an acid which is not volatile and which is not destructible by digestion, for it continues to act in a peculiar manner on the intestines. It appeared probable that it was lactic acid J it is formed, in fact, by a peculiar fermentation, to which the name of the viscous fermentation has been properly applied. Meteorological Observations, 14- 3 M. Liebig heated several pounds of sour-crout with water to the boiling point, and he added carbonate of zinc until no further eflPer- vescence nor any acid reaction was perceptible. The liquor, de- canted and filtered, deposited after evaporation to the consistence of a syrup, a great quantity of crystals, which after decoloration by charcoal were of a brilliant whiteness, and possessed all the pro- perties of the purest lactate of zinc. On precipitating the mother- waters by alcohol, a large quantity was also obtained ; no other or- ganic acid but the lactic was obtained, without even any notable quantity of acetic acid. Sour-crout contains acetic acid in so great quantity, that it may be recommended as a very good substance for its preparation. The lactate of zinc thus obtained has been ana- lysed by M. Thomson with results which show its constitution to be Carbon 24*72 Hydrogen 541 Oxygen .. .. 4.2-98 Oxide of zinc 26*89 The formula is . C6H16 O^ +ZnO = C6 H'oO^ + ZnO + 3Aq. It is extremely probable that the acid of sour turnips, cucum- bers, &c., is merely lactic acid. There are many other plants in which peculiar acids have been discovered, the composition of which is yet unknown ; it may be maintained, with great probability, that if all these acids were ex- amined according to their best characterized chemical relations, they would be reduced to a very small number. M. Liebig invites pharmacians to the investigation of the subject, calling to their re- collection the fact that the acid of fruits changes according to the period of maturation, for example, the fruit of the mountain-ash contains in the first months tartaric acids, then tartaric and citric acid, and lastly, malic acid alone. The preparation and examina- tion of these acids in many fruits, would lead to the most interest- ing conclusions respecting the connection of the organic acids. — Journal de Pharmacie, Nov. 1837. « METEOROLOGICAL OBSERVATIONS FOR NOVEMBER 1837. Chiswick. — Nov. 1. Stormy and wet. 2. Boisterous, with showers. .3. Overcast : clear with lightning at night. 4. Frosty : fine : clear and cold. 5. Overcast : fine. 6. Very clear : fine : slight fog. 7—9. Frosty and foggy. 10. Hazy. 11. Cloudy and fine. 12. Fine. 13. Over- cast: rain. 14.Fine: rain. 15. Clear and cold. 16.Fine. 17. Frosty: fine. 18. Frosty : hazy : drizzly. 19. Overcast: rain. 20. Clear: slight rain. 21. Cloudy. 22. Slight rain. 23. Densely overcast. 24. Cloudy. 25. Clear : frosty. 26. Frosty : rain. 27. Very fine. 28. Cloudy. 29. Clear and frosty. 30. Rain. Boston.— Nov. 1. Rain. 2. Cloudy. 3, 4. Fine. 5. Cloudy. 6, 7. Fine. 8. Foggy. 9—11. Cloudy. 12, 13. Fine. 14. Rain. 15. Fine. 16. Cloudy : rain early a.m. 17. Fine. 18, 19. Cloudy. 20. Fine: rain p.m. 21. Fine. 22. Stormy : rain early a.m. 23. Stormy: 24. Cloudy. 25. Fine. 26. Cloudy : rain p.m. 27. Fine. 28. Cloudy. 29. Fine. 30. Cloudy. r3< p . "^e* . -- O " s=' ^ ^" ^ ^ i ^* i ^ E St is' sJ &' i ^' K ;^ „• ^ ^ ^ ^ . . • ^- S te • « ■■* ^ -^ ^ i£ » !« «• I ^ K ^ S:' . ^ Sr' ^ i «5 Z tn (« tj co^TtvbocDOO-^'OobO'^rNdbt^— -« vpip OOOcoco•Qo6^6^>• cooc^cOJ-oi op i>t^9 r^ci Ttr^cocoo 0*01000 t^t^n■^lpo — ^0V0'0^^lp■rfcr>fp>-^^r)t^O00^■-'cn aooooo OiO^O^O o^o^c^o^o^o^o^c^o^o^o^o^o^O^o^o^o^o^o^o^Q0 o^o^ «S(N-Tj<^ -< o^ocoa^^>•co'^a^•^^<|>.■<*Tfo^o^ooGo '-Ofoa> OTflOOONC^OI"^— C*:»*0(Nco»OtO — C0C0'-' — O 0\0\0\ O o O o o o^o^o o^o^0^0^o o o^c^l0^0^0^0^o^o^6^c^o^G^l CCOC^7i0999--r9ao9a^QOO'^oioror--r^ 0^0^OOOOOOo6^ooa^ooc•OO<^o6^c^ooc)a^0^a^c^ C<ookoo«-^t^ (NC-oo* o^ d ^* H fa 02 OS H ^ H &^ c» ©S H ^ H fa 03 OS cH ^' H fa w 0^ H ^' H « O s^ ^ T M E LONDON AND EDINBURGH PHILOSOPHICAL MAGAZINE AND JOURNAL OF SCIENCE. [THIRD SERIES.] FEBRUARY 1838. XXII. On a neix) Property of Nitre. By H.F.Talbot, ^55'., i^.2?.S.* 5. 1. 'T^HE property of nitre, of which I purpose to commu- -■- nicate a short account, is one which appears to me to have an immediate bearing upon the fundamental doctrines both of double refraction and of crystalline structure in ge- neral ; and I think it requires that some modifications should be made in the received theory on those subjects. In general, crystals are formed by successive depositions of layers of particles on a small primitive nucleus. For in- stance, when a hot solution of some salt grows cold, we ob- serve the crystals grow and extend themselves in a manner analogous to vegetation. Or if the crystals have geometrical figures, these appear at first of the smallest size and gradually increase in all their dimensions. The crystalline structure may be destroyed by igneous fu- sion. For instance, it is stated that quartz which has been fused is destitute of the double refraction which characterizes it in its natural state. I have not tried this experiment myself, but I believe that it is the received opinion, that the structure not only of this, but of all crystals, is destroyed by fusion, so as oot to be recovered in growing cold. Nevertheless the following experiment decisively shows that this opinion is erroneous. Put a drop of a solution of nitre on a small plate of glass, and evaporate it to dryness over a spirit-lamp ; then invert the glass, and hold it with the salt downwards and in contact with the flame. By this means the nitre may be brought into * Communicated by the Author. Fhil Mag, S. 3. Vol. 12. No. 73. Feb. 1838. U 146 Mr. H. F. Talbot on a new Property of Nitre, a state of fusion, and it will spread itself in a thin transparent film over the surface of the glass. Removed from the lamp it immediately solidifies, and the film in cooling cracks irregularly. As soon as the glass is cool enough, let it be placed beneath the microscope (the polarizers being crossed, and the field of view consequently dark). We shall observe the following phaenomena. In the first place the nitre appears very luminous; a proof that it is in a crystalline state, and not amorphous, as (after fusion) we might have expected to find it. For if it had lost its crystalline structure it would produce no more effect when laid beneath the microscope than a thin sheet of glass would do, that is to say, it would be absolutely invisible, and the field of view would remain dark. If its crystalline structure were imperfectly restored on cooling (so as to present a confused assemblage of minute crystals) the field of view would appear also imperfectly and irregularly luminous, according to the accidental positions of the small crystals. Neither of these results however takes place, but an entirely different one, which would hardly have been anticipated. For the crystalline structure of the fused nitre is perfect ; that is to say, that the film appears very luminous, and imiformly so, 'as if it were a thin slice which had been taken from a large crystal of the substance. In order to see how perfectly it is crystallized, select any portion of the film for observation, and turn it slowly round in its own plane upon the stage of the microscope. Its brightness will be seen gradually to fade, and finally, in a cer- tain position, to be altogether extinguished. Now when this happens it will be seen to be uniformly dark over its whole surface, and the smallest irregularity in this respect would of course immediately manifest itself by contrast with the rest. Consequently every part of it acts together, as if it were a portion of one and the same crystal. But this does not continue indefinitely; for if we carry the eye over the whole of the dark surface which I have described, and which frequently extends in breadth over a space double or triple of the field of view, we shall come abruptly to its boundary, and shall see it succeeded by another portion of the crystalline film which is luminous. If now we darken this second portion (by again turning round the glass plate to a certain extent), in proportion as we do so we shall see the first portion recover its light. Proceeding in this manner, we shall find that the whole crystalline film which is spread on the glass consists of ten, Mr. H. F. Tnlbot on a new Property of Nitre. 147 twenty, or a greater number of these separate portions, each of which is a perfect crj^stal in itself, but altogether uncon- formable to the remainder. Moreover we shall easily per- ceive that the cracks which took place in the film during its cooling are the boundary lines which separate these diiferent portions ; and that after each crack commences a new crystal, which has no connection whatever mth respect to the position of its axis^ with the preceding one. These successive cry- stalline spaces are however, of course, in the most perfect juxtaposition; and their general appearance and effect may be compared to a sort of mosaic pavement formed of slabs of black and white, or coloured marbles, very irregular in form and outline, but accurately fitting each other. It appears then to follow as a consequence from this expe- riment, that the crystallization of melted nitre does not take place in the usual way by the formation of a primitive nucleus and the deposition of layers of molecules upon it; but that we have here a new sort of molecular action brought into evidence, by means of which considerable portions of crystal are formed at once, and pass from the fluid state into that of a crystalline solid with an axis in a determinate direction. We also see that whatever be the nature of the force which determines this direction, it often extends to a considerable distance. But since other portions of the fluid are disposed in solidifying to assume another direction of axis, this different tendency causes the film to crack at the point where the opposite forces counterbalance each other, and to separate into several inde- pendent crystals. §. 2. 1 now come to relate another property of nitre equally remarkable with the foregoing; and as these experiments are generally successful, and easily exhibited, I trust they may be considered as some accession to our knowledge of molecular action. Let a film of fused nitre be obtained in the manner already mentioned, and then let it be allowed to cool during three or four minutes. The plate of glass should be turned round upon the stage of the microscope until the crystalline film is darkened as accurately as possible. Things being thus ad- justed, let the observer touch the film with the point of a needle, while he is observing it in the microscope. He will perceive that the touch immediately produces a lu- minous spot on the dark surface, and this spot will slowly ex- pand itself in all directions like a luminous wave. This is a very curious object, but difficult to describe. Its motion is ex- tremelyirregular, its outline continually shifting and changing, and assuming different colours, until finally in four or five U 2 148 Col. Francis Hall's Meteorological Observations minutes it overspreads every part of the field of view, which by this singular process has been metamorphosed from a space ahnosl entirely dark, into a luminous one, mottled with all manner of colours. Should the observer happen to have quitted his instrument in the mean while, and during his absence this change have taken place spontaneously, he would hardly be able to persuade himself that his adjustments had not been deranged, and some new object placed before the microscope. Tins very beautiful phaenomenon no doubt arises from the following cause, viz. that the crystalline state or arrangement of particles which nitre assumes at the temperature at which it first solidifies after fusion, is no longer suitable to it when grown perfectly cold ; so that its condition is then one of un- stable equilibrium which the slightest force is capable of sub- verting. By touching it with a needle a disturbance is pro- duced, which propagates itself from the disturbed point throughout the entire mass. But even if it is not touched the same change will take place spontaneously a few minutes later. If however we touch it prematurely, as, for instance, during the first minute after it has become solid, this change does not take place. We may then trace lines or letters upon the darkened film with the point of a needle, and these lines will appear lumi- nous, in consequence of the crystalline particles which the needle displaces being thrown into such positions as to de- polarize the light. But this does not disturb the rest of the field of view, which remains quiescent for several minutes after, and then changes spontaneously, as I have endeavoured to describe. XXIII. Meteorological Observations made during a residence in Colombia between the Years 1820 and 1830. By the late Colonel Francis Hall.* ¥F the materials of science could be gathered only by the *■ scientific, the following collection of observations would be a useless labour; but it frequently happens that in distant countries the opportunity of observing natural phenomena falls to the lot of those very ill-fitted in most respects to profit by it. The genius of a Humboldt, like an incantation of sci- ence, descends upon the New World but once in a series of ages. The most that can be done by an ordinary observer is to offer his mite, a single stone towards the pyramid of know- * Communicated by Prof. William Jameson, of Quito, to Sir W. J. Hooker, F.R.S., and by him to Phil. Mag. made in Colombia between the years 1820- Cfw^ 18S0. 149 ledge, in the hope that he may casually prove useful, and with such humble pretensions can scarcely be deemed importunate. Should even this apology barely extenuate the sterility of a ten years' residence in a country so admiral)ly varied and rich in natural phaenomena as Colombia, something further may be urged in excuse of" the military traveller, obliged frequently to hurry through the most interesting parts, and to vegetate whole years in others of minor importance ; without books, without instruments, without resources; fettered too often by the chain of his own daily wants and sufferings, and fallen on a time when every species of local or traditional informa- tion, every glimmering of philosophic research, had been buried and obliterated amid the storms and struggles of the revolution. The geographical features of Colombia have been portrayed by Humboldt with an accuracy which renders further descrip- tion superfluous. It is however impossible to traverse this ex- tensive territory without being struck by the physical phae- nomena of a country where height produces the effects of latitude, and where the changes of climate, with all the con- sequent revolutions of animal and vegetable lile, are brought about by localities, to which we find litde analogy in Europe. The equatorial seasons, as is well known, are merely the wet and dry ; and though the Spaniards, influenced by European recollections, have given the former the name of winter " in- vierno" it is during this period that nature revives from the vegetable torpor which the scorching tropical heats produce in the low-lands, in almost an equal degree with the frosts of northern climates. In the vast plains which extend to the south and east of the great chain of the Andes, the rainy sea- son observes an invariable order. The Orinoco begins to rise in April, and attains its maximum of increase in July and August, when the immense savanas which extend to the base of the Andes are converted into the appearance of an inland ocean. It decreases from this period, and the summer is reckoned from October to April. In the mountains, on the contrary, the rains commence about the former month, and predominate, with intervals of fair weather, till May or June. The winter of the low-lands to the west and north of the Cor- dillera, both on the Pacific and Atlantic coast, is governed by that of the mountains, but with several curious local va- rieties. Thus, the rainy season of Guayaquil is nearly as regular as that of the plains, being reckoned from the middle of December to the middle of May; while the thick forests which, further to the north, cover the provinces of Esme- raldas, Barbacoas, and Choco, produce by their constant eva- poration an almost perpetual deluge. Wherever, on the con- 150 Col. Francis Hall's Meteor olo<:ical Observations trary, the Cordillera recedes to some distance from the coast, as is the case with parts of the Venezuelan chain, the inter- mediate country is parched by a drought often of several years. Maracaybo, and a considerable part of the province of Coro, are instances, where sandy plains, scantily shaded by Mimosas and thick plants, afford shelter and subsistence only to flocks of goats and asses. The coast of Rio Hacha is equally dry and sterile till it approaches the foot of the isolated ridge of Santa Marta ; while the Goagira territory, interposed between Rio Hacha and Maracaybo, is regularly inundated every year, and consequently, though destitute of streams, maintains considerable herds of cattle and horses, a circum- stance to be ascribed to the vicinity of the Ocana branch of the Andes, which extends, with its clouds and thick forests, almost to the confines of this province. The whole Peruvian coast from Payta to Lima is an additional instance of the same fact, where the recession of the Andes from the coast is marked by sandy deserts, which the industry of the Incas had rendered productive by artificial irrigation. In the valleys, and on the table lands of the mountains themselves, the cul- minating summits produce great variations in the distribution of moisture. The city of Caraccas, situated at the foot of the Silla, has the benefit of a regular, though mild rainy season; while within a league there are spots which suffer several years of drought. Popayan, placed at the head of the sultry valley of the Cauca, and surrounded by lofty paramos^ has nine months of continued rains and tempests, attributable to the clouds which are driven in opposite directions from the moun- tains, till they encounter the hot ascending air of the valley. In that part of the ancient kingdom of Quito now called the Department of the Equator, the mass of Chimborazo inter- rupts the passage of the clouds from south to north, so that while the western slopes are deluged with rain, the elevated plains of Riobamba to the east recall to the imagination of the traveller the deserts of Arabia Petraea. Following the same mountain-chain towards the city of Quito, we observe the storms arrested between Cotopaxi and Pichincha over the valley of Chillo, while two leagues further to the north the climate of the village of Pomasqui is so dry as to have given it tnfe name of Little Piura. The manner in which rain is formed and precipitated at various elevations seems to illustrate and confirm the theory of Leslie. In the regions oi paramos, i. e. from 12,000 feet upwards, the encountering aerial currents, unless in the case of some strong agitation of the mass of the surrounding atmo- sphere, are of a low and nearly equal temperature. The rains, inconsequence, assume the form of thick drizzling mists, made in Colombia bet-ween the years 1820 and 1830. 151 known by the name of Paramitos, On the elevated plains we find the showers more or less sudden and violent, according to localities which give rise to a mixture of currents more or less variably heated. Quito, for example, is situated on what may be called a ledge of the lofty mountain of Pichincha, and overlooks the valley of Chillo or Guaillapamba, furrowing the adjacent table-land, in which the therujometer often rises to 80° in the shade. The encounter of portions of the atmo- sphere thus variously heated produces showers as sudden and heavy as those which generally distinguish tropical chmates. On the slopes of the Cordillera the rains are generally vio- lent, for the sam^ reason. Looking to the hygrometrical state of the atmosphere, as it results from observations made on the table-lands of the Equator and the coast of the Pacific, we find it to vary from 0° in the damp forests of Esmeraldas to 97°*1 on the elevated plain of Cayambe; the experiments in both places being made during June and July, the summer months both of the coast and mountains. The average medium for the low-lands is 23°*85 ; for the Cordillera 44°*36 of the hygrometer con- structed upon Leslie's principle; but we are in want of suffi- cient data for those elevations which approach the limit of perpetual snow. To judge however from a small number of observations made on the mountain of Cayambe, at 12,705 and 14',217 feet of elevation; and at the hut of Antisana at 14,520 feet, where the hygrometer was found to give 16°*5, 13°-9, and 30°-3, it would not seem that the dryness of the atmosphere increases in ratio of the elevation, at least in the neighbourhood of snowy mountains where a continual moi- sture is exhaled, and heavy mists sweep over the soil towards the evenings even of the fairest days. To estimate the general distribution of temperatures through the vast territory of Colombia, we may conveniently consider it as divided into five zones. 1. That of the level, or nearly so, of the ocean. 2. That of small elevations, from 500 to 1500 feet. 3. That of the slopes of the Cordillera, from 2000 to 7000 feet. 4. That of the elevated plains, or table- lands, from 8000 to 10,000 feet. 5. That of the Paramos^ from 11,000 to the limit of perpetual snow. 1. The degree of heat at or near the level of the ocean is modified by a variety of local circumstances, which may be ranged under the following heads ; Proximity of the sea ; of great rivers or lakes ; of lofty ridges of mountains ; of ex- tensive forests; of contiguous elevations, which impede the circulation of air and produce reflected heat. The various combinations of these circumstances may be considered as affording a rule of the increase or diminution of temperature. 152 Col. Francis Hall's Meteorological Observations o Thus, La Guayra, situated on a sandy beach backed by a precipitous wall of rocks, has no counterpoise to the excess of heat but the sea breeze, and the remote influence of the ridge of the Silla, which nowhere reaches the limit of per- petual snow. Humboldt considers it in consequence as the hottest place on the shores of the New World, (Personal Narrative, vol. iii. p. 386) the mean annual temperature bein«r 82^*6 ; yet the observations I made during some months' re- sidence in Maracaybo, give an annual mean of 84'^*63 ; nor is this surprising, when we consider the localities of both places. In Maracaybo the sun's rays are reflected from a barren sandy soil, scantily sprinkled with Mifnosas, and prickly plants; the mountain chains are too remote to have any influence on the atmosphere, so that several years frequently pass without any regular fall of rain. The vicinity of the lake, no doubt, acts slightly as a refrigerant, but the city is built on the border of its outlet to the vsea, where it is both narrow and shallowest, and is consequently heated nearly to the temperature of the incumbent atmosphere. Add to this the small sandy eleva- tions to the north, which intercept the partial effect of the sea breezes, so that they are scarcely felt, except in the months of December and January, when the thermometer sometimes sinks to 73°*0 ; yet the medium even of these two months is not less than 81°-0, while that of La Guayra from November to December at noon is, according to Humboldt, 75°*8, and at night 70°*9 (Pers. Nar., vol. ii. p. 387). Rio Hacha is situated on a sandy beach ; the sea breeze blows with such violence that boats can scarcely land between ten in the morn- ing and four in the afternoon : these winds however, sweep- ing over the hot plains of Coro and Maracaybo, have but a partial effect in lowering the temperature, the annual mean of which is l°-98 less than that of Maracaybo. I never saw the thermometer lower than 75°-0, nor above 89°'0. In Santa Marta the average of the coolest months is 82°*25. The thermometer however never rose during my residence there above 87°'0. The soil is sandy, and the city is surrounded by bare rocky heights to the north and south, which counter- poise the cooling influence of the Sierra nevada (snowy moun- tains), from which it is but a few leagues distant. The tempe- rature of Barranquilla, a village situated on the river Magda- iena, about 18 miles from its mouth, is nearly the same with that of Santa Marta ; for if on the one hand the air is re- freshed by the evaporation from a damp soil covered with luxuriant forests, and the vicinity of a large river ; on the other it is beyond the reach of the sea breeze, and the in- fluence of the mountains which operate in Santa Marta. The made in Colombia between the years, 1820 and 1830. 153 annual mean is 82°*20 ; that of Cumana is, according to Humboldt, 81°-0. The breezes which sweep from the gulf of Paria over the wooded Birgantine chain probably contribute to lower the temperature. We have thus, on a calculation of six points on the Atlantic coast of Colombia, a mean annual temperature of 82°'56*. The shores of the Pacific, as far as the latitude of Payta, are subjected to other influences, being almost entirely covered by damp luxuriant forests; while the ocean itself is cooled, as Humboldt observes, by the winds which blow constantly from the south. This, however, is more perceptibly the case from latitude 8° to 13°, where the air is cooled to an average of 71°-8. Betwixt 9° north latitude and 3° south latitude, if we may trust to observations made at the five points of Panama, Esmeraldas, el Morro, the island of Puna and Guayaquil, the annual mean is 80°* 11, being 2°-45 less than the mean of the Atlantic coast. A notable difference also arises from the su- perior elevation of the Pacific chain of the Andes, and its more immediate vicinity to the coast ; while the Venezuelan branch, with the exception of the Santa Marta ridge, is both lower and more inland. 2. On penetrating into the interior of the country and ex- amining the temperature of small elevations, we may take as forming an aggregate specimen of the whole country, 1st, the damp wooded valleys of the Orinoco and Magdalena; 2nd, the forests which border on the Pacific; and, 3rd, the immense plains of Venezuela, alternately flooded and parched with excessive heat. Humboldt assigns to the valley of the Orinoco a mean temperature of 78°*2 The small number of observations I have made on that of the Magdalena, would give a mean of nearly 83°, which I should scarcely think too high, considering the localities of the river, which flowing from south to north, affords no channel to the sea breezes. Its mass of water is also much less considerable than that of the Orinoco, while its numerous sinuosities, and the low ridges which border it in the upper part of its course, contribute to render the air stagnant and suffocating. The temperature of Honda, at 1200 feet of elevation, is as high as that of any part of the coast, except Maracaybo. The unbroken forests which extend from the roots of the Quitenian Andes to the shores of the Pacific have a much lower temperature, caused by the proximity of the snow-capped Cordillera, and the hu- midity which prevails throughout the year. Accurate observa- * I have not included Cartagena, because the number of observations is, perhaps, too limited to draw a conclusion as to the yearly temperature. If we take them into the calculation the annual mean would be 82°-86, which is probably too high. 154" Col. Francis Hall's Meteorological Observations tions give an annual mean of 76°'78, or l°-42 lower than the valley of the Orinoco, and 6^*22 lower than that of the Mag- dalena. The mean temperature of the plains of Venezuela is reckoned by Humboldt at 88°-4 [De Distribute Geog. PL, p. y2.) yet several reasons may induce the belief that this calculation is excessive. This illustrious traveller performed his journey during the summer season, when the atmosphere is heated by the reverberations from a parched and naked soil. Persons who have resided near the Apur^ state the climate in rainy weather to be cool, and refreshed by a con- stant breeze. It is only on the coast of the Pacific that the rainy season is the period of the greatest heat, when the air is still and undisturbed by those electric explosions so com- mon on the mountains and in the interior. The observations I made at Varinas and San Carlos, towards the beginning of the winter season, give a mean of 81°*0; and averaging the dry season at 88°*4, we have a yearly mean of 84°*7, which is probably the extreme or something bej^ond it. There is no doubt it is in the plains of the interior that we find the greatest heat during the dry season. In the level country called the valley of Upar, between the mountain ridges of Santa Marta andOcafia, I found the thermometer in the shade several times above 100°, and once as high as 108'^*0. The average of nine- teen observations, made at different points of this district, is 89^*09; but we must allow a considerable decrease during the months when the soil is covered with thick vegetation, and drenched by continual rains. As a general mean of the interior at small elevations, we may take 80°*67j or nearly that of Cumana. 3. The temperate mountain region lies nearly between the elevations of 3000 and 7000 feet. Below this may be con- sidered as a hot climate : such for instance is Valencia and the valleys of Aragua in Venezuela, the height of which is from 1500 to 2000 feet, and its mean temperature 78°, or 0°- 14 above that of Guayaquil on the Pacific; but the soil, stripped by cultivation of its ancient forests, imbibes freely the solar rays, which are besides reflected from the rocky ele- vations which everywhere surround the cultivated districts. The temperature of Caraccas (elevation 2904 feet) was fixed by Humboldt in his essay, De Distribute Geograph.PL, p. 98. at69°'6 ; but in his Personal Narrative, b. iv. c. xii. (vol. iii. p. 460) he considers 17°'2 of Reaumur = 70°*40 of Fahrenheit, nearly as the true yearly mean. My own observations during a residence of some months give 71°'40. The preference would be certainly due to Humboldt's calculation, but for some col- lateral circumstances deserving of attention. I heard it ge- nerally remarked in the city^ that the seasons had grown hotter made in Colombia between the years 1820 and I8S0. 155 since the earthquake of 1812. It would be difficult to ex- plain how the temporary evolution of volcanic gases, sup- })osing such to have taken place, could operate any permanent change on the surrounding atmosphere; yet other causes may have produced an effect falsely ascribed to the phaenomena most impressed on the imagination of the inhabitants. On looking over Humboldt's collection of observations for De- cember and January 1799, we find the thermometer seldom rise to 75°, and often sink to 59°, so that the mean of these months is about 68°. During the same months in 1821 the daily range was from 65° to 76°. I never observed it lower than 61^°, and on one occasion at 5 a.m. it stood at 71°. The mean of these two months is 70°'21, or 2°'21 higher than the estimate of Humboldt. The clearness and beauty of the sky during almost the whole period of my residence is also a cir- cumstance opposed to Humboldt's " Ccelum saepe nubibus grave quae post solis occasum terras appropinquant." {De JDistrib, Geog. PL, p. 98.) I remember but once to have seen a fog in the streets of the city. Future observations will show whether any change of climate has really taken place, or whether the differences observed be only such variations as may be frequently remarked in the same places between one year and another. The mean of the whole temperate moun- tain region may be reckoned at 67°*80, that is if we limit ourselves to the districts partially cultivated and inhabited. The declivities of the Andes, still covered with vast and humid forests, have probably their temperature proportionally lower. Thus the village of Mindo, on the western declivity of Pi- chincha, embosomed in humid forests, at 3*932 feet of eleva- tion, has a medium temperature of 65°'5, the same with that of Popayan. 4. The elevated plains of the Andes between 8000 and 11,000 feet, on which were anciently united the most power- ful and civilized indigenous nations beneath the dominion of the Lipas of Tunja and Bogota, and the Incas of Quito, and v/here the great mass of Indian population is still to be found, have a general medium temperature of 59°*37, modified how- ever by local circumstances, and particularly by the proxi- mity of the nevados. Thus the village of Guaranda, placed at the base of Chimborazo, though nearly 500 feet less elevated, is at least l°-0 colder than the city of Quito, sheltered on all sides by the ramifications of Pichincha. The city, again, is above 1°*0 warmer than its suburbs on the plains of Aiia- quito and Turupamba to the north and south. Riobamba is about 200 feet below Quito ; yet its situation in an open plain bordered by the snowy mountains of Chimborazo, Tungura- gua, and La Candelaria renders the climate colder and more 156 Col. Francis Hairs Meteorological Observations variable; while the town of Ambato, only 300 feet lower than Quito, but built in a nook of the river which runs near it, and shut in by dry sandy elevations, has a climate about 2°*0 milder, so that sugar-cane is cultivated in its immediate vici- nity. The treneral uniformity of temperature, which spreads a certain monotony over tropical regions, is joined, at great elevations, to a daily variability, which must exercise a consi- derable influence both on vegetable and animal life. The thermometer, which often sinks at night to 44°-0, rises in the sun, wherever there is reflected heat, frequently to 120°'0, be- ing equal to the heat of Jamaica ; while in the shade it seldom exceeds 65°*0 : so that, on passing from shade to sunshine, one is immediately exposed to a difference of above 50°'0, and in the course of twenty-four hours to nearly 80°'0. The shade, in consequence, even on the hottest days, imparts a feeling of chilliness, while the solar rays seem to scorch like the vapour of at heated oven. The same difference is per- ceptible on the Paramos. At the foot of the Nevado of Santa Marta, I observed the thermometer at 5 a.m. sink to 22'^-0, and at 9 a.m. it rose to 73*°0 in the sun. On the height of Pichan, between Quito and Esmeraldas, elevation 12,986 feet, the thermometer stood at .53°*0 in the shade, and 83°'0 in the sun. On Antisana the difference was 22°*0 at the same time, but 34°-0 between 6 a.m. and 3 p.m. : when the atmosphere is calm it is much more considerable. 5. Although at great elevations, i. e, from 12,000 to 16,000 feet, it is difhcidt to form a series of meteorological observa- tions, such is the yearly equality of the temperature that a single day may be safely taken as a sample of the whole year. Nay more, a collection of observations made at similar heights, though in different places, will give a similar result to a series taken on the same spot. Thus, in the following table, there is little difference between the result of seven observations, made on seven different mountains, and the six made on that of Antisana. 1. 2. 3. 4. 5. 7. Paramo of Santa Marta Paramo of Cayanibe Paramo of El Altar Mine of Conderasto Volcano of Pichincha Mountain of Atacaso Nevado of Cayambe 15,000 ft. 12,705 12,986 14,496 15,705 14,820 14,217 22'' h\ a.m. 31 6 „ 42 8 „ 45 12 „ 46 1 p.m. 41 43 \\ „ Mean Paramo of Antisana General mean. . 14,520 39°-42 38 -58: six observ. 39 -87. made in Colombia between the years 1820 ajid 1830. 157 General Table of Temperatures and Elevations, Elevations. Places. Temper, ature. Ditto of Humboldt. Hygrom. Lat. Observations. 0 0 0 0 0 0 Cumana La Guayra *.. Maracaybo Rio Hacha Santa Marta Baranquilla '84°-63 82-65 82-28 82-21 81° 82-6 The Elevations here indicated by Zero are such as are too small to influence the tem- perature. Mean of the Atlan- tic Coast 82-56 81 -8 0 0 0 Panama Esmeraldas Guayaquil 81 -14 79-65 77-26 21°78 27-01 Mean of the Pacific Coast 79-35 500ft. 650 522 543 600 Valley of the Ori- noco 78-2 83" 84-7 81 -15 76-78 78-2 88-4 22-77 Valley of the Mag- dalena Plains of Venezuela San Carlos in ditto Canigue Forests of the Pacific Mean of the Inte- rior 80-61 83-3 1527 Valencia 78-25 2903 5823 6782 Caracas Popayan Loxa 71 -68 65-40 66-6 70-40 65-6 66-6 Temperate Moun- tain Regions ... 67-71 67 17 8694 9514 9724 Bogota Quito 60-49 60-47 58-75 57-25 60 8 59 40-98 42-03 Suburbs of ditto ... (Jayambe • Elevated Plains ... 59 24 59 9* 14,520 12,457-1 to • 15,727 J Antisana Farm ... Paramos of Cayam- be. El Altar, Pi- chincha, and San- ta Marta 38-58 39-16 30-3 Mean Temperature of the Paramos 38-87 * Humboldt ascribes to this region a yearly mean temperature of 54°, while the result of the mean temperatures of the various places he has instanced is 6064°. [ 158 ] XXIV. Sequel to anEssay on the Constitution of the Atmosphere, published in the Philosophical Transactions for 1826; *ix)ith some Account of the Sulphurets of Lime. By John Dalton, D.CL,, F.R.S. Sfc* IN an essay of mine on the constitution of the atmosphere, which was printed in the Transactions for 1826, I signified my intention of following it with a sequel of experiments to ascertain if possible which of the two views therein developed was most countenanced by facts. I now proceed to give an account of such investigations relating to this subject as have engaged my attention during a long period of years. It may be needful to premise certain facts which are, I be- lieve, universally admitted as indisputable; namely, that the atmosphere consists principally of two elastic fluids, azote and oxygen, either mixed by some mechanical law, or otherwise combined by a chemical principle in proportion nearly as four parts of the former to one of the latter in volume ; that the two elastic fluids may be obtained separately in a state of purity; that when thus obtained they may be mixed in all possible proportions; and that the aggregate volumes in such cases are just equal to the sum of the two volumes of the ingredients ; also, that any body which has a chemical affinity for either of them, so as to combine with it in a separate state, will also combine with it in the mixed state. It is also pretty generally admitted that oxygen and azote are capable of chemical combinations in five or more definite proportions, namely, 2 vol. of azote with 1 vol. of oxygen — forming 2 vol. of nitrous oxide. 1 vol. of azote with 1 vol. of oxygen— forming 2 vol. of nitrous gas. 1 vol. of azote with 1| vol. of oxygen — forming I^ vol. of hyponitrous acid. I vol. of azote with 2 vol. of oxygen — forming 2 vol. of nitrous acid vapour. 1 vol. of azote with 2^ vol of oxygen — forming 2| vol. of nitric acid. There does not appear to be a doubt of the reality of five combinations, but all chemists are not agreed as to the pro- portions of the volumes being precisely as above specified, chiefly because no general law has been found to obtain in such gaseous compounds. These compounds are never formed nor decomposed with- out manifest chemical agency; they all contain oxygen, but • From the Philosophical Transactions, 1837, Part ii. : an abstract of Dr. Dalton*s former paper will be found in Phil. Mag., First Series, vol. Ixvii., p. 310. Dr. Dalton oji the Constitution of the Atmosphere. 159 no portion of it can be abstracted from any one of them with- out some chemical operation; whereas nitrous gas will im- mediately seize the oxygen from any of the afore- mentioned mixtures, the same as if it was alone, whatever may be the proportions. Atmospheric air itself, or any artificial mixture of the two gases in the same proportion as common air, is equally affected by nitrous gas and by every other agent. Waving at present any consideration as to the nature and properties of the above chemical compounds, I shall now pro- ceed to state the means by which the proportions of oxygen and azote in mixtures of these two gases may best be deter- mined. Having been engaged in this investigation occasion- ally for more than forty years, I may be entitled to give my opinion on this important subject in practical chemistry. Various methods of analysing common air have been dis- covered in the last fifty years. I have principally directed my attention to three, namely, (1.) by the use of Volta's eudio- meter and hydrogen, or (2.) by nitrous gas, or (3.) by quadri- sulphuret of lime, to abstract the oxygen from the azote. First Method, by Voltas Eudiometer. Mr. Cavendish was one of the first to investigate the changes produced by firing mixtures of hydrogen and common airs in various proportions. (Vid. Philos. Trans. 1784.) The fol- lowing table will exhibit a lasting monument of his skill in effecting such an investigation. Many have attempted since to improve the methods of analysis, and have brought out re- sults widely differing from those to be derived from his table ; but it is now universally allowed that his results are nearer approximations to the truth than most of those we have seen since. His method was to take 100 measures of common air and mix them with various proportions of hydrogen, beginning with upwards of 100, and gradually descending till about 20 ^ then, firing each mixture by an electric spark, he marked the diminution of the mixture each time as under. The following results are extracted from Mr. Cavendish's Table, except the last column, " Amendment," which I have attached, for reasons assigned below. Exp. Common Air. 1. ... 100 measures mixed with 124-1 2. ... 100 3. ... 100 4. ... 100 5. ... 100 6. ... 100 Inflammable Air. Diminution on firing. Amend, ment. h 124-1 ... 105-5 ... gave ... 68-6 .. ... 64-2 .. . 66-3 . 65-8 70-6 ... 42-3 ... ... b-47 .. ... 61-2 .. . 64-9 . 60-6 331 ... 20-6 ... ■__: ... 47-6 .. ... 29-4 .. . 47-4 . 29-& 160 Dr. Dal ton on the Constitution of the Atmosphere, In the first three experiments no oxygen was found in the residuary gas; in the fourth a trace of oxygen was found; and in the fifth and sixth, considerable quantities of oxygen were found in the residues. It is obvious that Mr. Cavendish began intentionally with an overdose of hydrogen, probably expecting the diminution to be a constant quantity till the hydrogen became deficient, and then of course the diminution must be lessened; this was not the case exactly; but the reason is easily discovered, and it proves the accuracy of the observations. Hydrogen gas is rarely obtained quite pure : it frequently holds two or three per cent, of common air, detached from the water through which it bubbles and by other means; this air increases as more water enters the hydrogen bottle, till sometimes it amounts to ten per cent, at the last, as every one knows who has had a due share of experience. Now as Mr. Cavendish does not mention the purity of his hydrogen, we must try it by the means now generally known, as the re- ported results will guide us in the investigation. On looking at the column headed " diminution on firing " it is easy to see there is a discrepancy in the first three ex- periments in that column; if the hydrogen used contained any oxygen the diminution on firing ought to have continually decreased, whereas it was greater in the third than in the se- cond experiment. This it must be allowed is a proof of in- accuracy in one or both of the experiments ; but it is no greater error than usually occurs if we trust to a single experiment with any gaseous mixture. The average of two or three ex- periments on mixtures of the same proportions should be taken. The fourth experiment clearly shows that the hydro- gen contained oxygen as well as azote ; for a diminution of 61*2 would denote the union of 20-4' oxygen with 40*8 hydro- gen ; hence there must have been 1*5 common air in the hy- drogen. I have formed the column "amendment" by as- suming the hydrogen in ail the experiments to contain 4^ per cent, common air. If we combine the results of the third and fourth experiments, either by assuming Mr. Cavendish's diminution or that of the amendment, we shall obtain a very good approximation to the quantity of oxygen in atmospheric air, the former experiment giving too great diminution by reason of the excess of hydrogen and that containing some oxygen, and the latter giving too little diminution for want of the requisite quantity of hydrogen ; the former will give 20-98 per cent, oxygen, and the latter 20*92 per cent, oxygen in atmospheric air. If any doubt should remain as to Mr. Cavendish's hydrogen containing oxygen, it is removed by and on the Sulphur ets of Lime, 16 J the consideration that his first experiment would indicate 22*9 oxygen per cent, in air, which cannot be allowed ; and his last experiment that 8*8 oxygen must have combined with 20*6 hydrogen instead of 17*6, which is equally inadmissible. Since the period 1784? it has been found by various che- mists that in mixtures of oxygen and hydrogen, as well as in other similar ones, the electric spark does not always cause an explosion, and when it does a complete combination does not always take place, but that in the residue sometimes por- tions of both the ingredients may be found. The limitations and restrictions are now pretty generally known ; and with regard to the mixtures of common air and hydrogen, I pub- lished a letter in the 10th volume of the Annals of Philosophy, (New Series) page 304, in which I showed the limitations found by my own experience to be as under : Common air and hydrogen in which the oxygen is only yVth, or from six to seven per cent, of the whole mixture, do not explode. Common air and hydrogen in which the oxygen is only y^th, or seven per cent, explode imperfectly, leaving both oxygen and hydrogen. Common air and hydrogen in which the oxygen is from -j^^^th to T^.^T-th, or from eight to fourteen or fifteen per cent., fire leaving hydrogen and azote only. Common air and hydrogen in which the hydrogen is ^^Vu^^ to |th, or from fourteen to thirty per cent., fire and leave oxygen and azote only. Common air and hydrogen in which the hydrogen is Jth to y^^th, or from eight to twelve per cent., fire imperfectly, and leave oxygen, hydrogen, and azote. Common air and hydrogen in which the hydrogen is y^jth or less than seven per cent., do not explode. It should be observed that when one of the gases is so far deficient as not to allow of an explosion by a single spark, the effect may be obtained by a current of sparks for a longer or shorter period, accompanied by the requisite diminution of volume. In such instances where the effect is produced only by A current of sparks it may be proper here to suggest the reason. When mixtures explode perfectly but feebly, we see the flame, lighted by the spark, to run down the eudiometer till it reaches the water; when they explode still more feebly, the flame runs perhaps half-way down the tube and is extin- guished before it reaches the water. There scarcely can be a doubt that the extinction must be occasioned by the cooling effect of the eudiometer and of the intermixture of the mass of air which has to be heated by the feeble flame. Another Phil. Ma^r, S. 3. Vol. 12. No. 73. Feb, 1838. X 16^ Dr. Dalton o?i the Constitution of the Atmosphere^ spark in its passage will re-alight the flame, to suffer a quicker extinction, and so on till at length the combustion is com- plete. This reason will also explain the excessively slow combustion of azote by the electric spark, as ascertained by Mr. Cavendish, and as I have found by repeated experience. Query, might not this experiment succeed better by heating the eudiometer? From what we have stated it must be obvious that in order to secure the complete abstraction of either oxygen or hydro- gen from mixtures by Volta's eudiometer, we should avoid too near an approach to the limitations we have pointed out ; or if that cannot be, we should carefully examine the residue for both gases. The best test for very small portions of oxy- gen is undoubtedly nitrous gas ; for somewhat larger portions of oxygen or hydrogen, additions of those gases might be made so as to bring the mixtures into proportions capable of being exploded. Second Method, hy Nitrous Gas, The nitrous gas eudiometer is of singular utility on many occasions. No other can exceed it in accuracy when mixtures contain very little, as one or two per cent, of oxygen ; or on the other hand when nearly the whole of the gas is oxygen. But when the mixture of gases contains from twenty to eighty per cent, of oxygen, as in the case of common air, it is not the best when great exactness is required. The reason is well known ; when oxygen and nitrous gas combine, the combina- tion is not like that of oxygen and hydrogen, in uniform pro- portion. We may take one third of the diminution for oxy- gen, when mixed over water; but this can be considered only as a first approximation. One hundred parts of oxygen may combine with 1 30 or 360 parts, or any intermediate quantity of nitrous gas, according to circumstances. When only 1 or 2 per cent, of oxygen are expected I put in 5 or 10 per cent, of nitrous gas, and take one third of the diminution for oxy- gen. When the oxygen (freed from carbonic acid) is judged to be 90 or more per cent, pure, I put 100 parts of nitrous gas of known purity (say 98 + ) to 100 of the oxygen, and mark the diminution ; I next put in 40 nitrous and mark the diminution, and so on, till there is manifestly a slight portion of nitrous left; then this is to be removed by a small portion of oxygen; finally, knowing the quantity of azote which was in the nitrous gas, the rest must have been introduced by the oxygen. In this way I find a perfect agreement, whether the nitrous test or the hydrogen is used ; but with common air the residue and on the Sulphurcts of Lime, 163 is so enlarged with azote as to render the measuring of it not so accurate. Third Method,^ hy Quadrisulphuret of Lime, Quadrisulphuret of lime is an excellent test for oxygen, and may be applied to common air or to other mixtures of which oxygen is a part, up to the purest oxygen. As this and other similar compounds seem to me destined to act an important part in chemical operations, it may not be improper here to give some account of their origin and their constitution, as far as actual experiments have demonstrated. The alkalies and the alkaline earths that are soluble in water have been long known to combine with sulphur, both in the dry and humid way. In the last century they went by the name of hepar stdpkurisy or liver of sulphur, from their colour. Scheele was the first to use the quadrisulphuret of lime to abstract oxygen from atmospheric air. Lavoisier also made use of the same article ; but it was to De Marti of Spain we owe the most successful attempt with the quadrisulphuret of lime to abstract the oxygen from atmospheric air. His me- moir, printed in 1795, and reprinted in the Journal de Phy^ sique^ vol. lii. 1801, may still be read with interest*. All the heparSf when dissolved in water, have usually gone by the harsh name of hydroguretted sulphurets in our English works of chemistry since the commencement of the present century. In 1798 BerthoUet published an essay on the nature and combinations of sulphuretted hydrogen, with reference to the part it acts in the sulphurets. Proust afterwards controverted some of Berth oUet's opinions in the 59th volume of the JbwrwaZ de Physique i 1804?. Gay-Lussac, in the 78th volume of the Annates de Chimie, 1811, gives some important results on the mutual action of metallic oxides and alkaline hydrosulphurets ; he finds amongst other results that no sidphates are formed, that water is formed, that sulphites or sulphuretted sulphites, and often metallic sulphurets are formed ; and that conse- quently it is not possible to obtain the simple metallic bases of hydrosulphurets by means of hydrosulphurets of their oxides ; and that when a sulphuret is dissolved in water, no sulphate is ever formed, as is commonly imagined, but sul- phites and sulphuretted sulphites. Some proofs are after- wards given-j-. Vauquelin, in the 6th volume of the An7iales de Chimie et de Physique^ 1817, presents us with a laboured [* A translation of De Marti's Memoir appeared in Phil. Mag., first series, vol. ix. p. 250. — Edit.] t See also vol, Ixxxv. p. 11)9. X2 164 Dr. Dalton on the Constitution of the Atmosphere, series of experiments on the alkaline sulphurets, the chief ob- ject of which is to ascertain the state of the alkali in the sul- phuret, whether it is that of a metal or of an oxide. After many experiments on the sulphurets of potash, soda, and lime in the dry way, and one on sulphuret of lime in the humid way, the author sums up, and notwithstanding his leaning to the opinion that the alkalies exist in sulphurets in the state of metals, he is obliged at last to acknowledge " that it is pro- bable, hit 7iot yet demonstrated, that in all the sulphurets formed by means of the alkaline oxides by a red heat, these last lose their oxygen, and are united to sulphur in the metallic state as is the case with the other metals." Gay-Lussac, in the sequel of the same volume, page 322, in a memoir, ani- madverts on the before-cited paragraph; and allowing that sulphuric acid is formed when a sulphuret of potash made by a red heat is dissolved in water, he contends, according to a suggestion of BerthoUet, that the acid is formed in the instant of solution from the reciprocal action of the sulphuret .and the water, rather than from the oxygen of the potash and sulphur. This opinion is countenanced by several combina- tions of a similar nature, which he has adduced, and which are worth the attention of chemists. Without adverting at present to my own experiments, I may observe that Sir JohnHerschel,in an essay in the first volume of the Edinburgh Philosophical Journal, 1819, was the first writer who published an atomic view of the class of salts called sulphuretted sulphites, or hyposulphites, that accorded with what I had long entertained and demonstrated by reiterated and decisive experiments*. In the above-mentioned essay he showed clearly that the hyposulphurous acid is composed of two atoms of sulphur and two of oxygen, which united to one atom of base, as potash or lime, compose an atom of hy- posulphite. The formation of thojie of lime, potash, soda, barytes, and some metallic oxides is more particularly ex- plained. A saturated solution of hyposulphite of lime at 50° he found to be 1 '30 specific gravity f . In the 14th volume oi tXiQAnnales deChimie et de Physique, Gay-Lussac has given the principal results of HerscheFs essays on the hyposulphurous acid with some judicious re- marks, but he leaves the subject as one requiring further in- vestigation. ♦ See New System of Chemical Philosophy, vol. ii. Preface, and p. 105. t Dr. Thomson, in a paper on the compounds of chromium in the Trans- actions .of the Royal Society for 1826, disputes the accuracy of this con- stitution of hyposulphuroua acid. 1 have never had any doubt concerning it since 1815. and on the Sulphur ets of Lime » 165 In 1822 Berzelius published a memoir on the alkaline sul- phurets. The results of his experiments seemed to him con- firmatory of the previous notion of Vauquelin. Those ex- periments were on the sulphurets of potash and lime made in the dry way ; he made only one on lime, which agreed very well with the theory; but this very delicate experiment was not enough to establish so important a law of combination, and I do not find that any one besides has obtained the same re- sult *. Though I am not prepared to deny that sulphurets of po- tassium and calcium can be obtained by the process of Ber- zelius, I am quite satisfied that sulphurets of potash and lime, &c. may be easily procured in the dry way: of that of lime I have had numberless instances. As the compounds of sul- phur and the alkaline earths have been very little subjected to investigation by chemists in general, we find great vacancy in the accounts grven of them by the modern compilers of chemical books. For this reason I shall introduce here a few of the results I have obtained in a long series of experi- ments on this branch of chemical inquiry. Sulphuret ofLime^ in the dry way. In 1806 I formed, for the first time, the protosulphuret of lime by heating 50 grains of fallen lime with 50 sulphur in a covered crucible not quite air-tight, so that the escape and combustion of the excess of sulphur might be allowed ; when raised to a red heat an addition was made to the weight of the lime ; by repeating the dose of the sulphur and heating, a further addition was made to the weight ; but repeating the operation a third time seldom made any further addition. The weight of the compound was 65 grains ; it was a white powder with a tinge of yellow, not caustic, but bitter to the taste. In 1809 I examined this powder more minutely, and found it was best made by mixing equal weights of pure hydrate of lime and flowers of sulphur, putting the mixture into a covered crucible and heating it slowly to red ; when the escape of the sulphur fumes ceases, cool the contents, and again mix them with the same weight of sulphur as in the first operation, and again heat it as above ; at last it will be found that 32 parts of hydrate of lime = 24- lime have combined with 14 of sul- phur, or one atom to onef. In the work referred to I have stated that pounded lime and sulphur scarcely form any union by this process, and carbonate of lime and sulphur still less. * Annals of Philosophy, 1822. t See New System of Chemical Philosophy, vol.ii. pages 99 and 102. 166 Dr. Dalton on the Constitution of the Atmosphere, An ingenious pupil of mine, Mr. William Barnett Watson of Bolton, has succeeded in uniting lime and sulphur by heat; instead of taking pounded lime, which has a harsh gritty feel, he takes hydrate of lime, and expels the water by a red heat continued till 32 parts of hydrate are reduced to 24? ; this is a fine soft powder; when 24? parts of this pure and finely di vided lime freed from water are well mixed with 24- parts of sulphur and heated red in a covered crucible, a partial com- bination takes place, and an increase of weight to the lime ; this operation is to be repeated till the additional weight be- comes 14 grains, after which no further addition can be ef- fected. Mr. Watson found it require several repetitions. I have since found it may be effected by two or three only. This sulphuret is not used in eudiometry. Quadrisulphuret of Lime, in the humid *way. When sulphur and hydrate of lime in almost any propor- tions are boiled together in water, quadrisulphuret of lime is formed and dissolved in the water ; the solution is of a deep yellow colour, and has a very bitter taste. 1 have not seen in any author the proportion that ought to be used, nor the quantity and specific gravity of the liquid solutions. These are subjects which have engaged my attention. If lime is in excess, the liquid consists of lime-water holding in solution quadrisulphuret of lime. If sulphur is in excess, the hquid consists of water holding in solution quadrisulphuret of lime. I have long known that the ceconomical proportions to be used are 32 parts of dry hydrate of lime by weight with 56 of sul- phur, that is, one atom of lime with four atoms of sulphur. If more lime than that above be used, it will be found preva- lent in the residue; if more sulphur, then the redundant sul- phur will be found in the residue. A few ounces of the mixed ingredients may be gently boiled in an iron pan for an hour or more, stirring the liquor occasionally, and covering the pan with a lid to prevent the too free admission of atmospheric air. Or, in order to prevent the action of oxygen on the liquid, a flask may be substituted for the pan ; the materials may be put into the flask nearly filled with water, and the flask loosely corked may be immersed in a pan of boiling water so as to be almost covered by the water. The liquor to be pre- served should be kept in green glass bottles, nearly full, and having ground stoppers. After the boiled liquor has cooled and the sediment subsided, the clear liquor may be decanted, if it be strong or deep coloured the sediment may be washed with a little water, and another quantity of the liquor obtained and on the Sulphur ets of Lime, 167 of inferior strength. The sediment may be dried if necessary, and subjected to analysis, as I have mostly done. The quan- tity and specific gravity of the clear liquors should then be ascertained. The first quadrisulphuret of lime I made was in 1804-; it was very weak, since it only absorbed one fourth of its bulk of oxygen gas; the next that was made took its bulk of oxy- gen. The next, made in 1806, took 2^ times its bulk of oxygen. In these no account was taken of quantities or re- sidues of lime and sulphur. After this I saw the necessity of investigating, (1.) the quantities of lime and sulphur mixed; (2.) the quantity and specific gravity of the liquid obtained ; and (3.) the quantity and proportion of the materials left in the residue, in order that the rationale of the changes effected might be explained. From 1806 to the present time (1837) I have made no quadrisulphuret of lime without attending to all those particulars. In this period I have made it 23 times, six of which were in flasks, and the rest in iron pans covered as mentioned above ; the difference of the two methods I found to be very little : it consisted chiefly in traces of sulphuret of iron being found in the residues when pans were -used. A few trials of the various liquids obtained soon furnished me with a formula for ascertaining the quantities of sulphur and lime in a liquid of given specific gravity ; namely, mul- tiply the three leading decimals in the specific gravity of the liquid by 1 3, and the product will give the aggregate weight in grains of sulphur and lime in 1000 water grain measures of the liquid; of this aggregate y^^th will be sulphur, and j^^th lime. With regard to the residue after boiling and its analysis, it is obvious the residue must consist chiefly of sulphur and lime, which for want of due continuance of the ebullition have escaped combination ; and there may be some impurities in the sulphur, or the hydrate of lime may not be free from car- bonate, &c. ; but when the residue is comparatively small no material disturbance of proportions in the quadrisulphuret car^ take place. If the residue be chiefly sulphur, its quantity may be approximated by ignition ; but if lime is in excess, it may be estimated by the quantity of muriatic acid required to saturate it. The following table exhibits a selection of the principal varieties in the proportions of ingredients and products ob- tained so as to illustrate the foregoing statements. 168 Mr. Lubbock o;^ the Divergence of the numerical Coefficients Table of Proportions in Quadrisulphuret of Lime. 1 Quantities of hy- drate of lime and sulphur mixed. Proportions of lime and sulphur. Quantity of liquor obtained in water grain measures, and quantities of lime and sulphur in it. Measures of oxygen required to saturate 100 liquid. Quantity of residue when dried. Hvdrate. 120 = 90 lime -1-210 sulphur. Lime. Snlph. 4 : 9f aiOOof 1-056 containing 70 lime -1- 156 sulph. 900 56 = 16 lime + 40 sulph. 2 50 =37ilime -|- 50* sulphur. 4 : 5f 2200 of 1-0240 contain^ 21 lime -f 47 sulph. 400 20 = 12 lime -j- 4 sulph. + loss 3 150= 112§lime -1- 200 sulphur. 4 : 7+ 1450 of 1-146 containing 85 lime -f- 190 sulph. 2350 f 20 = 7 lime + 13 sulph. 4 96 =72 lime -\- 168 sulph.f 4 : ^ 2800 of 1-056 containing 63 lime -|- 141 sulph. 900 § 34 = 9 lime -f- 25 sulph. 5 35 = 26 lime -f- 140 sulph. 4 : 21-6 1600 of 1-037 containing 23-7 lime-l-53-3 sulph 600 § 83 all sulph. [To be continued.] XXV. On the Divergence of the numerical Coefficients of cer- tain Inequalities of Longitude in the Lunar TJieory. By J. W. Lubbock, Esq., F.E.S.\\ nPHE divergence of the numerical coefficients in the lunar -*- theory, made manifest by M. Plana's development of the expressions according to powers of m, presents a difficulty in a complete numerical solution of the problem, that is, a solu- tion intended to embrace all quantities which are sensible in practically ascertaining the moon's place v^ith the accuracy required for comparison with the best observations. But the following questions naturally occur : Is there any method of approximation which will serve to select the more consi- derable terms, rejecting others ? Is the divergence due chiefly to the development and expansion, according to powers of ?w, of the divisors introduced by integration? In the latter case the difficulty might be easily avoided ; but I fear that each of these questions must be answered in the negative. In order to illustrate this point I have selected indifferently two terms in the longitude amongst those in which this diver- gence is met with, and I propose to examine their construc- tion without introducing details which do not bear imme- diately upon the point referred to. * Boiled in a flask loosely corked. t Lost some of the ingredients by boiling over ; hence a deficiency. i Boiled in a flask with great care. § The oxygen was determined by especial care in these two cases. II Communicated by the Author. oflnequalitks of Longitude in the Lunar Theory, 169 X denotes the moon*s longitude, f and f ^ the mean anoma- lies, e and Cj the eccentricities of the moon and sun. X = Xi4^^^sin(f-f,) + Ai5^^^sin(2T-f + y + &c. ± = ri4 e e, cos (J-f,) +^5^^,003 (2 r-f + f/) +&c. f-f^ = cniJ-mnif 2T-? + g, = 2nif-w n^— en/ I find from the equation ("21 1065 o 12615 Q . 0 > Ti ■ '7 o 1 Ai4 = {■^^'^ + ^2" ^^ + ~6^^ +^'-| L^^"^"^ ^ ^'+&c.] 21 1233 g , 15333 ... = 4■^+"32-^+'-§r^+^^• 15 15 53 3^49321 ^3 , ^_ 1 T, . ».. . ^' ^i5=:r~T^-32^+-38l- TW^ + Sccj ["1+?^^+ ^ +&C. 1 15 173 2^4.8325 3 . Lubbock on the Lunar Theory, p. 193. 15333 It is evident that the divergence of the coefficients and ~7 is not due chiefly to the quantities 1 -J- tw + — w^ and l4-m^+ —- which arise from the expansion of divisors introduced by integration, nor is the expansion of these divi- sors according to powers of m a step attended with labour or difficulty, and on that account desirable to be avoided. The 12615 49321 diverging quantities - ■ and arise from the sum- mation of the following quantities in the value of — p-; 12615 __675 315 _^_^.^. 1687 64 "^ 32 "^ 64 4 32 16 8 49321 __ 9 39 ^ 63 13 49277 91 384 "" 16 16'"*' 4 "^32 16 384 24' 1687 49277 The principal terms are evidently and ~-^^^ : these arise from the coefficients r^^ and r,5 belonging to the same 170 Mr. Lubbock on the Divergence of the iiujuerical Coefficients arguments in the reciprocal of the radius vector ; so that with respect to these only, and to terms of the same nature in other arguments which 1 have examined, a tolerably approximate value would be obtained from the expression = tA{"} ri4 and r^^ are thus deduced from the well-known equation d^.r^ u. a ^ r^ T^ ^'^R Ti-ATy — — + — + 2/d R + -J— = 0 2d^=^ r a '^ dr If — =1+7) a^n^ = lu r^ a® 3 — -= -— -a'^ f -~a*p2-2a5 2'3 + &c. if p = XrnEnCos(int + q) t= ^ s? j)^ -2 o? j)^ ■\- &c. '^ dr a The differential equation gives for determining n at foot being the index of the argument. 21 , 1113 , , . 3 , .o 15 17 ri5 = — -g TO — g^ Wi2 + ^j5 7n3 + &c. - 2 I [2+«z+m*+&c.] { |-«^2+ ^»^^+ ^w^^+&c.} + 24 W4 + &c. i- . Lubbock on the Lunar Theory, p. 177. r 5 « 1 f 3 „ 221 , , 6133 ^ , „ i f r o ~] r 9 , 3 , , 12289 . , g "I - 2 j L2+'»;+wi'+&c.J j- g-w2— ^7»H ^56"^ +&c.| - ^ Wi4 + &c. j 33 of Inequalities of Longitude in the Lunar Theory, 171 Equating coefficients, 4221 1113 ^ . _8049__267, _9 _9265__759_3 l28~"l28" '*~"'"64" 16 "^ 8 32 32 2 3015 485 _ 6133 , ?21 _ 15 _ 12289 , 3 , 9 , 87 128" 128 -^^1^ - 384 "^ 16 8 64 "*" 4 "^ 4 "*" 16 1687 J _ 49277 In order to judge of the relative magnitude of these several fractions, I divide the numerators by the denominators, and retaining only whole numbers, I get _32_8 — 2^14 = 125 — 16+1—289 — 23—1-48 - 23 - 3 - 2 ^,5 = 17 + 13 — 1 — 192 + 0 + 1 + 6 Au = 105 ^15 = 64. The leading terms --289 and —192 arise from the deve- lopment of R, and virould be included in the following ex- pression : d^a^Sl . -j-^ -ix8- + 4^ = 0. cfr ^ r This approximation would save the calculation of some quantities, but it evidently could not be safely adopted, and it would still leave the calculation of i?, which is extremely troublesome. Very little trouble would be saved by not de- veloping the divisors introduced by integration, or the quan- titles in square brackets. Ihe quantities - and , which belong to the development of R, arise as follows, from a multitude of diverging fractions, andl think it would be impos- sible to give any safe rule for selecting the principal terms. 9265 _ 1161 __ 243 525 ,^__63 ^.^.j- ?^11 _ 1^ T28"~ 128 256"^ 128 "^ 4 8 8 "^ 8 "*" 256 128 4"^"8"+ 8 - 519^ 128 + 357 64" 693 64 33 5523 64 + 128 51 64 + 64 , 231 + 64 + 105 ^ 32 128 + 3483 256 +1+ 8 ^ 513 128 4- 3 3 8 4 + 3699 128 122^__ 81^ 3483 1 27 5]I3_ 3^ _3 _3^ 3699 15 256 " 128+256 + 4 + 8 + 128 16+8 4 + 128 16 5523 The term -^-- arises from the combination of the term 1 ^o 263 -— ?»* e sin (2 T— f ) in the longitude (5 a) with 172 Dr. Schleiden on the Development of the 21 9 . ,,, ^. . di2 -, ,1 , 3699 . — m^ Cf sm (2 i — ^J in ^ — and the term j— arises from 1233 the combination of ---- tr^ee^ sin (f — fy) in the longitude (S X) with -— m* sin 2 t in --^ — . These are the most consider- able, but it would evidently be impossible to employ with safety any rule of approximation which did not embrace other terms. In this and in other cases in the Lunar Theory it will be found that coefficients, when formed correctly, are made up by the addition of numerous small terms, which come from various sources : hence the danger of attending only to the leading or principal terms which may occur upon an incomplete exami- nation, hence also the extreme practical difficulty of the pro- blem in whatever manner it be approached. In the method which M. Plana has adopted, first, as is well known, the mean longitude of the moon is obtained in terms of the true longitude, and the true longitude is afterwards found in terms of the mean longitude by reversion. But the divergence of the numerical coefficients exists equally in the former expression, and does not arise in the operation of re- version. XXVI. Scrnie Observations on the Development of the Organic nation in Phcenogamous Plants. By Dr. M. J. Schleiden.* [With a Plate.] Nullo modo generationem explicasse judicare possum eos, qui ne ullam quidem partem, ne uUum attributum quidem corporis ex tra- ditis suis principiis explicuerunt, sed sermones saltem de ea re fecisse, utcunque doctos, vercs et elegantes. C. F. WoLFFy—Theo)ia Generationis. ALTHOUGH it must be granted that Linnjeus had a to- lerably clear idea of the metamorphosis of plants, yet the introduction of this doctrine and its reception into the higher botany takes its date from Goethe. Long, however, before Goethe, the ingenious C. F. Wolff had shown how fruitful this idea could be rendered ; but his work was little read by the botanists of the time, not at all understood, and soon forgotten. Thus the science, to its prejudice, did not gain possession of this doctrine through Wolff, in whose hands it would probably have become so fertile, but through Goethe, and owing to the manner in which it was introduced * From Wiegmann's Archivfur Zoologie, Part IV., Berlin, 1837. [The Editors are indebted to the kindness of Dr. Wood, of Bristol, for the translation of this paper.] Lond AEdin.Phil. Mag. Vol XH PL 3 Tig 5 J Bmit«, litK Organization in Phanogamous Plants, 173 by him, it has hitherto been of comparatively but little service. If we understand by the term metamorphosis the principle that a plant has only a certain limited number of different fun- damental organs, and that all other organs distinguish them- selves from these potentially, only inasmuch as the tendency exists in them of allowing a certain peculiar degree of develop- ment and variety of form, which, however, is not so absolute but that it can be suppressed under certain circumstances, allowing the usual form of the organ to manifest itself, — I say, if we lay down this principle as a foundation, it is clear that this doctrine must furnish the most important results for the science, and give it an internal unity which no other branch of empirical natural science has hitherto obtained ; that is, if this idea can be substantiated by fact ; and it must only be received so far as it can be proved, since as much as does not actually exist in nature and cannot be perceived by the senses, is no longer an object of natural science and can never serve to ex- tend our knowledge of the material world. C. F. Wolff adopted the only correct plan, that of the study of the development, and proved the identity of the greater part of the foliaceous organs quite satisfactorily. He was, however, not at all appreciated, and Goethe was the first who introduced the doctrine of metamorphosis, but not as an in- duction arising out of practical consideration of the process of development, but as the speculative result of the comparison of the different forms of the developed organ. Now such a comparison may certainly lead us to conjecture the existence of such a law, but can never lead to its absolute establishment. Goethe says in another place : *' Alle Gestalten sind ahnlich, doch Keine gleichet der Andern j Und so deutet der Chor auf ein geheiraes Gesetz." Analogy pervades all forms, — yet all unlike; The whole thus indicate a hidden law. Thus it was that the botanists received this important doc- trine, one which was capable of yielding such valuable results, Under a wrong light, since it was presented to them only as a philosophical idea, and indeed it seems as if a tolerably gene- ral conviction prevailed that the demonstration of what was true in the theory was not possible. At a later period Fran- cis Bauer, who like Wolff was no botanist, again had recourse to the only correct method, inasmuch as he traced the indi- vidual organs to their original forms, in order to explain their proper nature ; his investigations have, however, unfortunately become too little known and have been used to advantage by scarcely any one else than Robert Brown. 174? Dr. Schleiden o?t the Development of the In this manner has the doctrine of metamorphosis or the morphological design of the organs of plants gradually formed itself into a peculiar department of scientific botany j and at the same time that it has offered a field for the exertions of the most celebrated men, upon which they have obtained lasting honour, it has become the appropriate theatre for all friends of enigmas, dreamers, and dealers in paradoxes, and has served for the display of the most vi^onderful things, which have been unhesitatingly dignified with the proud name of Philosophy or Speculation. Speculation, however, is only admissible where our means of observation fail us ; and if it thrusts itself forward, desirous of taking the place of observation, we should do wisely to get rid of it as a tire- some guest. How much might we be in advance of our pre- sent position, even in the speculative sciences, were it not that speculation devoted itself to objects, which, consuming its best time and best powers, not only did not require it, but would even have been better without it I It is precisely in the history of development that examples of this sort are particularly frequent. If therefore the prosecution of this branch of science shall attain importance and become established in all its parts, it will not suffice that investigations be commenced on a bean or something of that sort which may conveniently be dissected with a penknife ; a much earlier period must be chosen, that of the first origin of the embryo. A ripe seed presents the young plant already provided with such manifold organs, that a wide field is here opened to mere speculation sufficiently extensive to render subsequent inves- tigations vague and unprofitable. Upon its first appearance the embryo is recognised as a mem- branous cylinder (PI. III., fig. 9 & 13) rounded and closed su- periorly, but open inferiorly, since the membrane constituting the embryo is invariably continued into the sac containing it (appearing indeed to be merely a reduplication of that sac) and filled with an organizable, for the most part pellucid fluid mass, which becomes gradually converted into cells, begin- ning from above downwards, (fig. 6 & 10) during which pro- cess the cellular nuclei also become apparent (fig. 12 & 24), which appear at all times to perform a principal part in the formation of cells. At this point a leading phaenomenon in vegetable life finds its explanation. The embryo originally consists of axis alone, and being closed superiorly, only al- lows a further development from within outwards, but is not limited inferiorly ; and by the secretion of organizable matter becoming transformed into cells, admits of unlimited prolong- ation ; whence not only the direction but the mode of growth Organization in Phccnogamous Plants, 175 of the stem and root, differing as they do, become intelligible. During the second stage of the development the upper end of the germ expands in a globular form, (fig. 6, 7, 11, 12, l^, & 15,) and from the sides of this globular extremity, in dicoty- ledonous plants, the two rudimentary cotyledons become de- veloped as cellular projections, their points being more or less free* (fig. 16 & 17). In these, as also in the stem it- self, the elongated cells and spiral vessels are not formed until a much later period : the mode in which this growth takes place was in its principal features described with per- fect accuracy by C. F. Wolff. In the monocotyledonous plants, on the other hand, an asymmetrical elevation is form- ed at the summit of the cylindrical embryo (fig. 8), which ultimately constitutes the cotyledonous leaf surrounding the stalk, and which also subsequently incloses more or less the terminal bud {-plumula) f . This process offers the second and greatest difference to which a plant can lay claim, namely, the antagonism between vertical longitudinal formation and horizontal superficial extension. All subsequent development of the plant, and every later formed organ, are only modifications of these two portions of the axis, the stem\ and of the lateral organs, the leaves. This an- tagonism therefore appears to be something original; indeed the axis is formed at an earlier period than the cotyledons, from which may be seen the great error of that opinion which consi- ders the stem to consist of adherent leafstalks, and the terminal bud to be an axillary one, as for instance Agardh does. The most important points of difference in the cotyledons are again repeated in the leaves also, which are indeed only after-forma- tions of those organs: thus for example we find in the Stapelice, in • Punctum vegetaiioniSf according to C. F. Wolff. f It will be seen from this descripdon of the process of development that every monocotyledonous embryo possessed originally a plumula exserta^ and that wherever this is inclosed, there must invariably be a fissure present, however fine it may be. The grasses have been usually understood to belong to the families with ^plumula exserta^ but quite incorrectly, since the-phirmila in this family becomes ^er/ec^ by means of an elevation of the cotyledon closed with the exception of a very fine slit (the outer closed leaf of botanists), and this portion of the cotyledon, like every other of its peculiarities, becomes repeated in the subsequent leaves in the analogous formation of the ligula, whilst the scutelluvi^ constituting the principal portion of the cotyledon, corresponds to the leaf itself. Some- times the cotyledon folds itself together once more, as in Zea Mays,vih\ch. formation has been falsely compared to the fissure of the cotyledon in the Aroidecc'f or it sometimes forms on its anterior surface small protuberances, which however cannot be considered as second cotyledons, since they are in connexion with the axis at a point lower down than the cotyledon itself j and a second leaf cannct possibly be formed beneath the earlier one. 176 Dr. Schleiden ofi the Development of the which the cotyledons are very small, that the leaves are also rudimentary, and in Cuscuta the absence of the cotyledons in the embryo even points to the subsequent habit of the plant. The close agreement between the cotyledon of grasses and the leaves has already been alluded to in the preceding note. The investigation of the laws of position of the leaves forms a very interesting section of this inquiry ; the manner in which the varying relations of foliage become developed out of the originally opposed and perfectly cotemporaneous cotyle- dons, until nature often appears to return at the extremity of a plant to the original type of two opposite leaves. The consideration of this subject would however lead me too far beyond the limits of these brief remarks. It will be unnecessary that I should make any remark as to the calyx and corolla being foliaceous organs, since that is universally received. I will merely remark that in all mo- nopetalous calices and corollas, those parts which at a later period are joined together, forming the single leaf, are in the earlier stages without exception so independent as to render all discussion as to the number of the individual parts superfluous, since it is a matter of investigation to be established by actual evidence. Every flower then has in its earliest development a regular construction, and the supposed abortions which some- times appear in the arrangement of the leaves, and which have often been so completely misunderstood, especially whilst the diversity of the laws as to number was disregarded, are therefore entirely unfounded, wherever they cannot be actually proved. The Euphorhicje have with injustice been denied the bene- fit of their original structure. Their involucrum is not form- ed out of five leaves, but out of two quintuple verticils, of which the outer one develops the glands ; these even exhibit earlier than the five inner leaves a middle nerve with evident spiral vessels, which cannot therefore be considered to be vasa recurrentia from the other. There can nowhere be found a better example of the original regularity of structure of the flower than in the grasses, in which the flower becomes at a later period so contorted by unequal development, adhesions, and suppressions of individual parts that every possible ex- planation has been offered excepting that which nature herself offers. For instance in Secale cereale, the spicula consists of a lateral rachis, on which about five alternating flowers are formed. The superior three of these, together with that por- tion of the axis which appertains to them, remain in a rudi- mentary state, whilst on the other hand the two inferior are at first perfectly regular in their development. In the axilla of every bractea {gluma auct.) we find a flower consisting of a Organization in Phceiiogamoiis Plants, 177 calyx ofthreeparts, each leaf of which is completely dividedfrom the others, equally large, and standing at the same height; the two inner leaves become gradually united, and form with the external one, which has grown disproportionately large, the later developed palece auct. Of course under these cir- cumstances the inner one possesses the two central nerves of the formerly separate leaves. With these parts belonging to the calyx there alternate three corollary leaves [squamnlce auct.), forming an inner circle, and in like manner stand- ing at the same height; of these, that which is directed to- wards the axis becomes at a later period abortive through pressure. We find also further, three stamina alternating re- gularly with these corollary leaves, the two inner of which, although at a later period, are thrust by the lateral press- ure towards the side of the ovarium ; lastly, the basis of the entire flower, the very short pedunculus, cannot, on ac- courlt of pressure, extend itself horizontally upon the se- condary rachis, and is therefore forced to ascend upon the inner side, by which means that part of the flower which is directed towards the rachis spiculcc assumes an apparently greater elevation than the outer does. In this manner proba- bly we may be able to explain in a simple manner the appa- rently complicated development of the flower in the Graminece. We will now pass to the consideration of the stamens. These are more deserving of attention, since some (among others Agardh, following Wolff", whom, however, he does not quote, although he is otherwise well acquainted with him,) have appeared disposed to give them the character of buds ; the opinions also concerning the formation of the anthers are not yet unanimous. It is evident likewise from the study of their development that the stamens are modified leaves, for they constantly ap- pear at a later period than the petals (although they after- wards develop themselves more rapidly) ; they stand at first higher up upon the axis than the preceding circle of corollary leaves, and alternate invariably with them; by this means, and from the smallness of the individual parts, the relative propor- tions can be much easier observed*, and for this reason they cannot be axillary buds of the calyx. * In some families the petals and sepals, (as is frequently the case with the stamens) or indeed other pcrigonial parts, consist of more than one circle of leaves, as, for instance, in the Berberidecc of 2-3 leaved, in the ThymelecB of 2-leaved circles; we can here therefore speak of opposition with as little correctness as in the LUiacces. Whenever actual opposition of the outer circle of stamens towards the inner circle of petals occurs, it will always be found that an intermediate circle of stamens has become abortive. Pltil. Mag. S. 3. Vol. 12. No. 73. Feb. 1838. Y 178 Dr. Schleiden 07i the Development of the The incorrectness of Agardh's view is also made evident by aconsiderationofthose flowers, in which the internode between petals and stamens is perfectly developed, as in some Cappa- ridece. The regularly formed leaf consists of a central rib, on each side of which there is a twofold cellular tissue, between which the nerves take their course. In this manner is the anther naturally formed, whose superior and inferior cellular tissue* is converted into pollen on both sides of the principal nerve ; thus is formed the anther with four cells, which we find to be the general law. I have found the anther before its bursting quadrilocular in more than one hundred families ; amongst these I may name Graminece, CyperacecE, Liliacece, Labiatcc^ Borraginea^ Scro- phularinece^ Synantherecc, Umbelliferce, RanunculacecB with its allies, Rosacece (Juss.), and the Leguminosce^ which alone constitute almost one-half of the entire vegetation of the globe. It has been often asserted that the anther could not originally be quadrilocular, since it springs open with two fissures only ; that is as much as to consider two chambers as one, because they have not folding doors, but simple doors placed close together. Properly speaking every anther really bursts open with four fissures; they appear however only as two because each pair lies at the sides of the common septum. The difference between quadrilocular and bilocular anthers of descriptive botany, (here however the Anthercc dimidiatce and some few others must be excepted,) consists in this alone : whether the valves detach themselves from the septum earlier or later, in the close observation of which we may distinguish every state of transition. Sometimes, though rarely, the original middle layer is not developed, and in this case of course the division into two lateral cells is not found. Still more rarely is the one lateral half of the leaf only developed into an anther, the other retain- ing its leafy character ; this condition is the type of the Maran- iacece, and occurs frequently as monstrosity in the conversion of the floral leaves into stamens, or of stamens into petals. In both cases, however, the course of the epidermis proves * The normal leaf, as is well known, exhibits upon its upper surface cellular tissue, different in structure from that on the under; to this we find that the pollen of the anterior and posterior cells of those compart- ments corresponds. It may perhaps be possible, and certainly not unin- teresting, to ascertain by experiment, whether or not the pollen of one of these compartments only possess the external characters of pollen, and likewise different functions in the process of imj)regnation, or whether in Dioecious plants one kind would produce male, the other female em* bryos. Organizaticyfi ifi Vhccnogamous Plants, 179 jncontrovertibly (what is likewise established by the study of development) that the pollen forms itself in the interior of the leaf, and that therefore the anther cannot be considered as a leaf rolled up either backwards or forwards, which produces the pollen upon its surface. If we carry back our investigations of the anther as far as its first appearance, we find that in every family it goes through just the same conditions, and that all the apparently deviating characteristics of this organ in the Orchidecc^ Asclepiadea;, Cu-- curhitacece^ Stylidece^ &c., are merely later unfoldings of the same fundamental type, and are only physiologically unim- portant modifications of the same plan, which nature, here as everywhere else where external differences of form only are concerned, has made the subject of so great and wonderful variety. The formation of the pollen takes place in this manner : the four groups of cells intended for the pollen separate them- selves from the remaining tissue of the leaf, their individual cells continually increasing, and in the interior of each proba- bly for the most part four other cells are formed, in each of which a grain of pollen is produced, upon which the original cells become entirely reabsorbed. The four pollen grains often appear to be developed in one cell, if we decline the assuming that the delicate cells, closely surrounding them, have been over- looked. SometimeSj although seldom, there are only two grains of pollen found in the larger original cell, for instance, in Po- dostemo7i ceratophyllum^ which in that case afterwards remain adherent one to the other, (figs. 29 and 30). Yet the quadru- ple number is undoubtedly the general rule, which explains the frequent occurrence o^polle?i quaternarium. If, however, the reabsorption of the original cells does not take place, or is not perfect, a very peculiar arrest of develop- ment occurs, which being the constant type in the OrcJiidecs and Asclepiadece, has afforded botanists abundant occupa- tion, whilst the entire peculiarity consists in this, that the pol- len stops short at an earlier point in its development. This same condition may be seen as a temporary stage in the de- velopment of the flower of Picea and Abies in January and February, in Finns in February and March, in which a loose waxy pollen-mass may be found imbedded in each division of the anther. At a somewhat later period we may see the four cells in Picea and Abies, in which the four grains of pollen lie closely united, and it ofiers a very pleasing spectacle when we observe under the microscope each grain expand itself by the absorption of water until it bursts its case in order to Y2 180 Dr. Schleiden on the Development of the escape, leaving the four cells emptied of their contents (figs. 25 to 28). In this way we are enabled to recognise in the formation of the anthers only a stage in the development of the lateral or- gans of plants. If we proceed further we next meet with the ovarium, the object and aim of the entire vegetable organization. In this we find all the constituent parts so closely condensed that their distinction appears very difficult, and it is here that the most extended stage has offered itself for hypotheses of all descriptions ; indeed many have advanced the most extrava- gant speculations, relying upon their powers of guessing more than upon their talent of observation, by which it cannot be denied some fortunate hits have been made ; of such Agardh's Organographie offers a series of capital examples. According to the general, and at present commonly re- ceived view, the ovarium consists of buds {ovula), which de- velop themselves on the borders of leaves (carpella). If we examine this view upon the usual grounds, we detect unfortunately a logical incorrectness in the reasoning which alone can be advanced and asserted in its support. And this is not the only case in which an entirely unfounded assumption has crept into science long ago, and which supported by tra- dition has been esteemed sacred and impregnable, so that no one has ventured to deprive the assumed deity of its veil, and show that this adoration had been prostituted before a vain puppet. We observe continually a sort of dread for the high authorities which first introduced such a doctrine ; whilst in natural science nature herself should be the only lawful au- thority, and it is only in cases where she cannot be made sub- servient to our inquiries that any other testimony should be tolerated. If we contemplate the entire range of the vegetable world we shall recognise this universal law, that a bud never forms itself on a leaf but from the axis of the plant or its derivative organs alone. If therefore the ovula are considered as buds, we must, as matter of course, conclude that the placenta is an altered axis. But what are the grounds which have been ad- duced in order to controvert this simple and necessary con- clusion ? 1 . The well-known phsenomenon in Bryophyllum ; and 2. A monstrous development of gemmae on the leaf of a Malaxis and an Ornithogahim observed twice. The latter case is an abnormal product, and therefore least of all suited to establish a general rule, which is in con- tradiction to all known phaenomena, and which will, as well as Organization in Phcenogamous Plants. 181 the other case, be presently explained. The first case consti- tutes, however, a singular exception. But I cannot help expressing a doubt as to its being really an exception, and would ask if the said leaf may not perhaps be a foliaceous ex- panded stalk. How long have such grounds been deemed sufficient to overturn a general rule, naturally deducible out of the principle of unity ? It is further a recognised axiom in logic, that an hypothesis is by so much the more allowable, the easier it explains all phaenomena connected with it, and the less it stands in need of other hypotheses for its support. Now I ask, in order to take an extreme case, what abnormal assumptions are not rendered necessary in the explanation of the true placenta centr^alis libera according to the usual mode, as, for instance, in the Plumbaginece (figs. 20 to 23) ? Here the five carpellary leaves would have been bent inwards, have uni- ted by their edges, then have separated themselves once more from their edges, would have again expanded, and then have united to one another anew ; and lastly of at least ten ovula, nine would be abortive, the remaining one having in addition taken a remarkable position upon the summit of the central pillar ; and be it remarked, all this would occur without the possibility of discovering even one step of so complicated a process in the plant itself. It would indeed be universally necessary to have recourse to the supposition of an abortion in all uniovulate ovaries, a circumstance not in the least corro- borated by an appeal to nature. The second and opposite case is however almost more dan- gerous still as respects the usual view; for when the entire surface of the carpellary leaf bears ovules, as is the case in the Gentianece^ Nymphccacece^ Butomecc, &c., I know of no tenable explanation of this phaenomenon deducible through the common hypothesis. This has made it necessary to have recourse to many explanations ; sometimes the ovula are re- presented as formed on the edge of the carpellary leaf, some- times on the central nerve*, and sometimes on both. * Thus in a work by a M. Eisengrein, entitled " Die Familie de)- Schmet- terlingsbluthigen mit besonderer Hinsicht auf Pflanzen-Physiologie,^'* it is advanced as a law that in the LeguminoscB the ovules are formed on the middle nerve. Independently of the circumstance that the position of the different parts of the flower shows that in this family the convoluted bor- ders of the leaf are the seat of the ovules, M. E. might easily have convinced himself of the uselessness of his lengthy observations, had he taken the trouble to examine a bean-bud with a tolerably strong magnifying glass. I feel indeed disposed to consider the book altogether as a pathological symptom of the spirit of the age. It combines the most barren trifling with empty comparisons, in the style of a modern, but already expiring school, and this is put forth as philosophy ! The book discloses as little investi- 182 Dr. Schleiden on the Development of the In this manner an extravagant view has been thrust upon the science, founded upon the weakest possible grounds, the circumstance itself been loaded with difficulties, and the na- tural condition most completely neglected. We shall see further on how easy is the explanation of the only apparently contradictory fact of the placenta parietalis, by the assumption that the placenta is a formation of the axis [Axcngehilde\ which indeed may be proved, without the assistance of hypothesis, from the well-known modifications of the stalk. But if we pass over to the investigation of nature, we find — to commence with the most simple conditions — that each individual carpel- lum is at first quite isolated, constructed similarly to every young leaf or lateral organ of the plant. It is not until a much later period of their development that it begins to di- rect its edges inwards when the carpellum is closed, or to ad- here to the neighbouring edges when the pistil is unilocular and many-leaved. Amongst those families which in this respect again deviate from the ordinary plan, must be included the Graminece and CyperacecE. In both families their development shows that the ovarium consists of 07ie carpel only. In both families the two anterior* stigmata for the carpel are merely a further de- velopment of the ligula ; the posterior, however, which is so often abortive in the grasses, is analogous to the surface of the leaf, and the ovarium itself to the sheath of the leaf. We can now take a reviev/ stage by stage of the entire de- velopment of the pistil, from its first appearance as a flat foli- aceous organ, until it becomes divided into ovary, style, and stigma. This will enable us to obtain a correct idea of these parts, for which little has hitherto been done, as organs whose use and function, completely different, have received the same name. The ovarium then is that portion of the leaf which incloses the omda ; the style, that portion which is rolled up and does not develop ovula^ whose object is to conduct the prolonga- tion of the pollen tubes; and lastl}^, the stigma is the free termi- nation of the superior part, whose object is to receive and hold the pollen. This result is attended again with manifold consequences. We find in the nomenclature of organs, for instance, that en- tire families to which styles had been ascribed, as the grasses, gation of living nature as of the "physiological principles" paraded in the title ; and the author shows himself to be at least thirty years behind the most common-place botanical works of the present day, and even not au niveau with such men as Grew and Malpighi. * If the ovarium be viewed in a direction from the axis. Organization in Phcenogamoiis Plants* 183 possess stigmata sessilia only. Some few species belonging to these families, as Lygeum and Zca^ possess an actual style. It has always appeared singular to me that the same botanists who, on the one hand, have advanced the position that the styles offer the surest means of determining the number of the carpels, because every carpel has its corresponding style, should, on the other hand, have ascribed only one carpel to the grasses, although they at the same time speak of several styles. A true style occurs equally seldom in the majority of the i^i- \m\y Etiphorbiacece ; indeed in Euphorbia, Ricinus, AndracJmc, Crozophora, &c., in which more than one style ha^ been de- scribed, there is either none at all, but merely stigmata sessilia bifida, or only one style present, as for instance in Euphor^ bia, in which three carpellary leaves are united superiorly so as to form a tube, although a short one. We find the style also to be deficient in most of the Alismaceco, Malvacece, Phytolacea ; they possess only stigmata : in some of these plants, for instance Ricinus and Phytolacca, the so-called sur- face of the stigma sinks down with its papillas as far as the basis of the carpeKleaves. It is equally incorrect to speak of 7'ami styli in the Composites, which are in fact only forms of the double-lobed stigma. Hitherto litde more than a tradi- tional meaning has been applied to the words style and stig- ma, and this has been still more corrupted by means of pre- tended logical distinctions. It will, however, be easily seen that if botany is to be treated in a really scientific manner, the terms must be based upon ideas, which being derived from the nature of the vegetable structure, imply certain actual organic differences, and can be adopted in a sense so strict as to avoid the possibility of including the most various things under the same term ; or on the other hand of separating iden- tical organs by giving them different terms. The prosecution of the inquiry into the process of development also very sim- ply settles the old dispute as to whether the style possesses a canal or not. Since each style is formed either by the rolling together of a single leaf (apocarpous fruit, Lindl.) or through the union of the edges of many leaves (syncarpous fruit, Lindl.), it must always possess a canal, which certainly cannot be always recognised as a cavity upon making a section of the style in the open flower, since the internal layer of cellular tissue ( Tissu conducteiir, Brongniart, properly speaking the epidermis of the upper surface of the leaf,) becomes so ex- panded through alteration in the form of the cells and the ex- udation of mucus in the intercellular spaces, that the indivi- dual cells become completely detached from their connection, 184f Dr. Sclileiden oji the Development of the and lie loosely imbedded in the mucus, as for instance in the Orchidcce^ many Liliacea^, &c. These are then the important points from which nature does not deviate in the vegetable organization, whilst she manifests the greatest possible variety in regard to the external differ- ences of form. The form of the stigma exhibits the most wonderful variations of shape, and upon this account has been of all parts that most frequently misunderstood. The style also, and even the carpel-leaf, offer many varieties, especially the latter, from the formation of spurious septa by cellular ex- crescences, as in the Aroidecc. We find further that the car- pel leaf in the Coniferce is not closed ; in the Resedacece three are united to form one open basin, strictly closed in most families, frequently bent inwards towards the axis, and then turned backwards again, so that the placental portion forms a belly, and the style ajypears to spring from the base, where the transitions of development may be studied, beginning with the Euphorbiacece^ through the Phytolacece, Alismacece as far as the Borraginecc^ and Labiatce^ and lastly in the en- tire family of the Dryadece, The young ovarium in the La- biatce andBorraginecr, for instance, is usually a two-leaved car- pel (fig. 2), whose edges however are very soon joined to form the style; and by the development of the ovulum the part inclosing it becomes expanded both above and below, whilst the style, the upper end of the leaf, is incapable of this eleva- tion and distention. The fruit of the palm presents a very similar appearance, in which the embryo stands at first erect soon after impregnation has taken place ; as the seed however advances to maturity, the inner side of the ovarium does not enlarge with it : thus the point of the embryo becomes fixed and serves as a central point, about which the radicula de- scribes a quadrant, to which figure it is limited by its partial development : in this manner is formed the embryo horizon- talis lateralis. There has been a great deal of time lost in the discussion of such apparent abnormalities, which would not have been the case had surmise not taken the precedence of investigation. If wenowturn to the placenta and ovulum, and, which will be the most advantageous course to pursue, commence with the simplest form, we shall select that where no carpellary leaf is present, which is without doubt the one of all others that pre- sents the most insurmountable difficulties if attempted to be explained according to the usual theory. This state is found in Taxus, for instance, where the entire female flower is no- thing else than the terminal leaf-bud of the axis to which it Organizaiio7i in Phcenogamous Plants, 185 belongs. The leaves are arranged in the customary spiral direction, even to the extreme summit, and no one leaf implies in the slightest degree an adaptation to the female part more than another (fig. I). The axis, as is customary, terminates here also in a small protuberance (the 2)unctwn vegetationis of Wolff'), and this is the nucleus of the ovule. Thus the axis forms the second antagonistic power [differenz) of the plant, forming as it does the female portion, and we are now in a condition to perceive that impregnation and fructification consist in the conjunction and balancing of the two most im- portant antagonistic forces the plant possesses, viz., those of the horizontal and vertical structure. We will however calmly prosecute the course of our inves- tigation further. The terminal portion of the axis constitutes therefore the nucleus of the ovule, and is the onlij actual and never-failing portion of the entire female organ, whilst all other parts are or may be partially deficient; some in this plant, some in that. Now this end of the axis is frequently found bent, so that its point becomes reflected upon itself (ovulum anatropum\ and adheres to that portion which retains its proper direction [r'apJie), a process which may be easily recognised on inspection. In this condition {ovulum ex nucleo nudo constans) we find the ovule in many families, as for in- stance in the SantalacecE, Rubiacece^ Dijpsacecs^ Cuscutece, As' clepiadecB, &c.* There is indeed no reason why the nucleus may not be de- veloped without suffering this reflexion of its axis, (as ovulum atropum ex nucleo nudo co7istans,) although I have never yet met with an instance of the kind. The formative power concentrates itself in such a manner around this extreme point of vegetation that what subsequently appears as separate lateral organs is here consolidated in the shape of a sheath-like envelope. These leaves inclosing the stalk of the last bud are termed ovular membranes, and are di- stinguished by the total absence of spiroidal vessels, which are proper to the raphe, or that portion of the ovulum which is not divided into nucleus and integument; the presence of these vessels therefore would show that the membrane under exami- nation was only an apparent ovular membrane. Still it some- times happens that at a much later period — after fructification * R. Brown includes the ApocynecB also under this head ; but they have a simple integument. In these, as well as in the AsclcpiadecSy it is not the nucleus which becomes developed in the interior after impregna- tion, but the sac of the embryo, which becomes at an early period filled with opaque albumen, which is visible after impregnation as a dark kernel perceptible through the integument. 186 Dr. Schleiden on the Development of the has taken place — vascular bundles may be detected in the ac- tual integuments; this is, however, very rare indeed. Now such a simple envelope [integumentum simplex mihi)* is found under these circumstances : 1. Without the axis being bent (ovulum atropum cum in- tegumento simplici) in Tax2is at the flowering time, in the CtC' prcssinecCi Juglandecc^ and Ceratophyllece, 2. Or else the axis suffers the reflexion above described, whereby the envelope becomes adherent to the prolonged axis {raphe) ; (ovulum anatropum cum i?itegume?ito simplici). To this class belong the Abietinecc, Synantherece^ Lioheliacece^ Campanulacea;, Goodenoviea, Lentihularicc^ Scrophularinece^ Oroba7ichece, Gesneriecje, Sesames, Labiatce^ Bignoniacece, Pole- moniacece^ Co?ivolvulacece, SolanecE, Borraginea, Gentianecu, (including the Menyanthece^ which have likewise only one in- tegument ; for the external hard covering, separable from the ripe seed, is nothing more than the epidermis of the integu- ment, whose cells have become much lignified) ; further the Apocyiiecjo^ XJmhelliferce^ JRanunculacecc^ Loasece, &c. Lastly, there is a second covering formed, which incloses the point of the axis {integumentum externum et internum mihi), and here also both modifications may occur. 1. The axis remains straight, as for instance in the Poly^ gonede (fig. 4), Cistinece, Urticece, and a portion of the Arnidece, 2. Or else the axis becomes bent upon itself, adhering to the external integument (figs. 20 to 23). In the remainder of the family of" the Aroidea^ may be observed all possible states of transition, from an elongated axis, the reflected portion of which, with its integuments, hangs free (as is also the case in Rajffiesia according to R. Brown), to the complete adherence, in which case the unreflected portion of the axis appears as raphe. Further, we must include amongst these all remain- ing monocotyledonous plants. R. Brown has not indeed ex- pressed himself in positive terms on this point with respect to the Orchidece ; they possess, however, decidedly both integu- ments, which are only to be observed in their earliest stages (fig. 5), since the embryo sac having been very early developed has at the time of impregnation almost entirely compressed the micleus, so that one would be induced to consider the very thin integument as the memhrana nuclei, I will content myself with adducing the following among the dicotyledons as exam- ples, to avoid occupying too much room with the mere enu- * I feel myself obliged to abandon the usual terms testa and memhrana interna and others which are taken from the ripened seed, and are nowhere applicable, and which would only tend to confuse ideas of things on account of the many errors historically attached to them. Organization in Pha^nogamous Plants, 1 B7 meration of names, Nympheeacece and Cahomhece^ the Plumha- ginece, Rcsedacecc^ Passiflorce, Caryophyllcce^ and Cruciferce. Mirbel was the first who published any detailed account of the general formation of these integuments of the nucleus ; but although he has partially observed the phaenomena ac- companying their formation, he has evidently been far from understanding them, and could not therefore clearly explain the process ; and it is indeed scarcely possible to collect from his own words what was his real opinion of the matter. We are indebted to R. Brown, who has struck out so many new paths in this and every other department of botany, for the first correct account of their mode of formation in the Orchi- dece in 1831, and at a later date (in 1834?) in his dissertation on the female flowers of the Uaffiesia^, in which he extended his observations to many other families. Fritsche has how- ever furnished the most detailed account of this subject in Wiegmann's Archiv, but he has confined his observations en- tirely to one species, and that the least favourable to such an investigation on account of its compressed growth and ana- tropous ovule. He has also neglected to take accurate mi- crometrical measurements, a point of the utmost importance here, by which alone he would have been able to avoid some errors. Thus, for instance, the expansion of a cylinder un- derneath a given line, and its contraction above it, are cir- cumstances which can only be ascertained in objects so minute by means of comparative measurements, since, of course, every stage of the process cannot undergo examination at the same time, and these differences are of the greatest importance to the true appreciation of the subject. In this manner Fritsche has fallen into the error, on the one hand, of supposing that both integuments are a simultaneous formation produced by the inflexion of the first fold into the body of the ovule, and on the other hand he has viewed the formation of the inner integument in too confined a manner, as a mere fold of the epidermis nuclei. The plan which nature adopts is simply this : — The exam- ple I shall select is that of the atropous ovule, for instance of the Polygonecc (fig. 4), as being the most simple. At a certain distance below the apex of the original protuberance an ideal line may be recognised, intended as the basis of the nucleus (fig. 4? Z>.), which does not afterwards increase in thickness. Above this line the apex forms itself into the nucleus^ and be- low it the substance of the axis expands and forms a protu- berance (fig. 4 Z>.), which extending itself as a kind of mem- [* Account of the results of Mr. Brown's researches on these subjects will be found in Phil. Mag. and Annals, N. S. vol. x. p. 437> and Lond. and Edinb. Phil. Mag., vol. v. p. 70.— Edit.] 18S Dr. Schleiden on the Development of the branous fold gradually covers in the nucleus, (Integumentum jyrimum aut internum mihi ; Secondine Mirb. ; memhrana in- terna auct.) Sometimes soon after, and indeed almost contem- poraneously with this, sometimes later*; sometimes immediate- ly below the first protuberance, at other times at some distance from it (as for instance in many PolygonecE and Cistinece)^ we may next observe a second protuberance, which, as the second integumentf, covers in the first. {Integumentum secundum sive externum mihi ; Primine Mirb. ,♦ Testa auct.) The first- formed integument certainly does frequently consist only of a fold of the epidermis of the 7iucleus; nevertheless we do find a tolerably thick parenchyma taking part in its formation in almost all those families which form no second integument, and also in some which possess both coverings, as, for instance, in the Euphorbia ceco, Cistinecn, and Thymelece. In the case of these three families, a peculiar process takes place, namely, upon the seed becoming ripe the external integument is gra- duall}' absorbed, until nothing but a thin membrane is left, usually described as epidermis testce, or in the Euphorbiacece it has been given as arillus ; and on the other hand, the actual modified epidermis testcc has also been described as the aril- lus^ for instance, in the Oxalidece, The apex of the original papilla, which develops itself as nucleus, varies exceedingly in its size in proportion to the entire ovule, if examined in the different families. It often forms a long and nearly cylindri- cal body, as in Loasa and Pedicularis\ in many cases it is shorter, so that that portion of the ovule in which no distinction has taken place between nucleus and integument (the whole being like a fleshy distended stalk), is by far the more predo- minant, as in all the Synantherece^ Canna^ Phlox^ Polemomium : it consists again, in some instances, merely of the extreme point of the papilla itself, as in Convolimlus ; or nothing more than an ideal point remains, which can no longer be distinguished as an independent body, above which, however, a protube- rance develops itself, and thus forms a micropyle, as in the Dipsacece, Of course the process I have been describing becomes con- siderably modified in individual points, either through the uni- lateral development of the o\\\[e{ovulum campylotropum Mirb.), * This is most conspicuous in Taxus, in which the second integument (fig. 1 b.) does not exist until after impregnation has taken place {cupula auct). t I observed this to occur very distinctly in Hydrocharis and Val- lisneria ; and, as Richard's analysis shows, all other true Hydrocharidecs have atropous ovules. Endlicher's attribution of an anatropous ovule to this family {Genera Plantarum^ p. 160) is probably derived from a partial in- vestigation of Stratiotes (which perhaps does not belong here), and which has been extended to the remainder of this family. Organization in Phcenogamous Plants. 189 or through the reflexion above described {ovulum anatropum). I should however be far exceeding the limits assigned me were I to insert here a detailed account of the numberless in- dividual peculiarities which I have met with in the course of my observations. I will content myself with remarking that the Quartine of Mirbel does not exist : what he describes is nothing else than a temporary endosperm in those families, in which the embryo sac displaces the entire nucleus at an early period, although it is not destined to form albumen at a later period by means of a permanent endosperm. These integuments experience manifold changes during the ripening of the seed, so that the original number can seldom or never be recognised in the ripe seed. Sometimes all the integuments become consolidated so as to form but one ; at other times, and this is more frequently the case, the integu- ments become separated into different layers of cellular tissue, of various degrees of development, in which case the homo- geneous tissue can easily be separated from the heterogeneous. In this manner the integument of the ripe seed may sometimes be divided into as many as five layers, although only one or two membranes, or, as in Canna^ no complete integuments were originally present. But since it frequently happens that the greatest variety may occur in the ripe seed in this particular in one and the same family*, as has been already related of the group Menyanthece ; whilst, on the other hand, the entire absence, or the presence of one or two integuments in the ovule appears to be very constant in the different families and groups, it may possibly be more advantageous to return entirely to the old terminology of Richard, and only speak of an episperm in the ripe seed, the different positions of which may then be more minutely characterized, whilst at the same time greater accuracy maybe observed in the description of the ovule. Many interesting results may probably be ascertained when these investigations shall have been extended over all the families ; already the small circle of my own observations has afforded many hints. It is remarkable, for instance, that not a single monocotyledonous family possesses fewer than two integuments, and the first impression caused by a review of the different families given above is, that amongst the dicoty- ledonous the majority of the monopetalous families is furnished with but one integument, whilst the polypetalous generally possess two. * Indeed in the same genus. Thus one portion of the Salvia; possesses spiral cells in the epidermis of the integument of the seed, and in the re- mainder they are absent. [To be continued.] 190 XXVII. On ElectrO'7nag7ietic Motive Machines. By Mr, Francis Watkins. [With a Plate.] To the Editors of the Philosophical Magazi?ie and Journal, Gentlemen, pERMIT me in the pages of your next number to describe -*- two or three modifications I have made in electro-magnetic motive machines, for 1 am incHned to think that any new ar- rangement of the working parts will interest those of your readers who hope to see realised the expectations which have been so confidently held out of successfully employing electro- magnetic power for propelling machinery. We are indebted to Professor Joseph Henry, New Jersey College, Princeton, for the first hint, and for the first con- trivance wherein electro-magnetic power is made to produce continuous motion. In one of Silliman's American Journals for 1831 will be found Professor Henry's original description of his electro- magnetic motive machine, and as I believe it is not very ge- nerally known, I venture upon a brief description of it in this place. It consists of an electro-magnetic beam, supported horizontally on an axis passing through its centre of gravity, with two permanent steel bar magnets arranged vertically, one under each pole, of the horizontal electro-magnet, with their north poles uppermost. Without entering into the details of the method of changing the polarity of the mobile hori- zontal electro-magnet, the working of the machine will, I conceive, be sufficiently understood when it is stated, that by a timely alteration of the magnetic polarity (which is effected by changing the direction of the electric current inducing the polarity) of the horizontal electro-magnetic beam, an alternate series of attractions takes place between its poles and the poles of the vertical permanent steel magnets, and thus a recipro- cating rectilinear motion is obtained by the vibration of the horizontal electro-magnetic beam. Since Professor Henry's publication several modified forms of apparatus have been produced for exhibiting the electro- magnetic power. In England, as far as my knowledge ex- tends, little as yet has been achieved beyond the construction of some very ingenious trifling machines or toys for exhibiting continued rotatory motion by this agent. Several philosophers on the Continent have published ac- counts of experiments, and of machines made by them, their Lond.&Eain.PlxLlMag:Vol.X[I ^^^<^ A ^^s-^- MTWaikiriss Electro Ml. /'I, '^^ AfotireMachinej- Mr. Watkins on Electro-magnetic motive Machines, 191 object being the practical application of electro-magnetic at^ tractive force, and one of them supposed he obtained a power equal to that of half a man. I refer your readers for an account of their labours to Part IV. of Mr. Taylor's new and highly useful quarterly publication, entitled '* Scientific Memoirs." The public have also been recently favoured with notices of a small electro-magnetic machine, said to per- form wonders, on the other side of the Atlantic ; but in spite of the talent already brought into play, it must be acknow- ledged that it is yet reserved for some happy genius to hit upon the right arrangement which shall economically employ this electro- magnetic power on a sufficiently large scale to be used with the desired success. In the August number of your valuable Journal for 1835 (Lond. and Edinb. Phil. Mag. vol. vii., p. 107,) you favoured me by noticing an arrangement of the electro-magnetic mo- tive machine which I had then contrived. This machine, like all others that I am acquainted with, was founded upon the fundamental principle of Professor Henry's, namely, that of varying at a particular period the polarity of the trans- ient electro-magnet, thus obtaining a succession of magnetic attractions. It is true that Henry only obtained an alternate rectilinear motion, while his followers succeeded in producing continual rotatory motion; still the principle remained the same. Henry's principle being universally adopted, it is clear that all those who attempted to carry out the idea of obtaining a motive power by this principle are only entitled to the credit of those modifications of the arrangement which may emanate from their mechanical ingenuity, and to such credit only do I aspire in the present communication on my machines, which I will now describe. Fig. 1. (Plate IV.) is a representation of a working model of an electro-magnetic motive machine ; «, «, «, a, are four vertical cylindrical permanent steel magnets suspended by two mahogany cross stages Z>, Z>, which are themselves upheld by two mahogany columns c, c. The electro-magnets d^ ', Z>', two soft iron electro-magnets with their bent parts underneath the board ; c, c, c', c\ and d, d, d', d'^ are four flat bent per- manent steel magnets, arranged like the arms of a windmill, and attached to a norizontal moveable axis, which is supported on a hollow wooden column e. The arrangement of the axis could not be shown in the Mr. Watkins oft Eledro-mametic motive Machines. 193 •b figure, but it has a contrivance of points dipping successively into the mercury in a divided wooden cup. One partition of the cup is connected with one element of the battery, while the other partition is in communication with the other element of the battery. The communicating wires from the division in the cup proceed down the hollow wooden column to the coil of wires surrounding the soft iron, while the battery wires pro- ceed up the column, but not in contact, and finish by being connected to two separate cups with mercury, in which revolve two small circular discs of platinum affixed to the axis, one on each side of the divided cup, and supported by two wood arms from the top of the column. The dipping points are so in- sulated and arranged on the axis that they reverse the direction of the current in the wire coils, and so effect the order of po- larity in the soft iron magnet : this being accomplished at the right period the motion of the permanent steel magnets is obtained. Two pullies are attached to the axis, bands from which will urge trifling pieces of machinery. I have constructed a more simple form of motive machine than that of fig. 2. Plate IV. It has only one electro-magnet and two permanent steel magnets. The axis or shaft is of the same description as that with the four magnets : it works re- markably well, and the axis having only to carry one system of magnetic arms revolves with great velocity, and raises nearly an equal ^weight in the same time and distance as that with the four magnets. The batteries I employ for obtaining the electrical currents are small, and constructed upon the plan proposed by Pro- fessor Daniells, King's College, London, and called by him the constant battery. This plan of the battery I consider to be original and the best devised for constant action and conveni- ence of manipulation. When we reflect that magnetic attractive force is the funda- mental principle upon which the motive machines act, the limited space through which this force operates to a working amount, and our imperfect means of developing its powers, it may be excusable if we pause before giving in the present state of our knowledge an unreserved assent to the ultimate success of employing its agency as a prime mover on an extensive scale. I have mentioned that many trifling machines or philoso- phical toys, in addition to those I have just now described, have been constructed, and plenty more, I have no doubt, will be brought forward and work very successfully ; and when they operate by continued rotatory motion of the shaft, carry- PMLMag. 6'. 3. Vol. 12. No. 73. Feb. 1838. Z 194* Mr. Watkins on Elcctro-mamdic motive Machines, Q- ing delicately suspended mobile magnets, the shaft and mobile magnets may be made to revolve with considerable velocity. Many hundred revolutions in a minute have been assumed as the rate of speed of some of the already constructed re- volving shafts and mobile magnets ; but is it imagined that magnetic attractive force alone actuates the machine so many times within that period, and causes the great velocity? for such a condition of things, I respectfully submit, cannot exist. We certainly have mechanical arrangements which enable us to alter many hundred times in a minute the direction of the inducing electric current about the soft iron ; but the polarity of the soft iron cannot be changed so rapidly if Herschel and Babbage*s law be just, for they say ^Hime is an essential ele^ ment of induction-^" and it is by the induction of the electricity in the wire coils embracing: the soft iron that the magnetism in the soft iron is induced, and thereby an attractive force gained. I am not aware that it has yet been determined what is the exact time necessary for the full development of the in- ductive process, yet experiments tend to prove that it is within the limit of many hundred times in a minute; and as it is ne- cessary for the constant employment of the magnetic attractive force in its full effects that the polarity of each of the opposing poles of the fixed magnets should be in opposite states to the advancing poles of the mobile magnets, it is clear that if the time has not transpired necessary for the transient magnet to acquire its full and proper polarity, there will not be the whole effective magnetic attractive force gained. What is it then that aids the rapid revolution of the mobile magnets and carrying shaft when they are light and very free to move, unless it be, their own inertia, when they have acquired a certain velocity, kept up, and contributed to at in- tervals in the revolution by the original prime mover, viz. magnetic attractive force? Now this inertia is a power that is soon overcome by additional friction, as may be observed when a very small portion of weight is added to a shaft which without the additional weight revolves rapidly. The diminution of velocity is immediately perceptible ; and supposing that the slight extra weight thus counteracts the advantage gained by the inertia, then under such circum- stances we have only the primitive magnetic attractive force of the machine left for mechanical purposes. I find these conditions maintained in my small models, and also in one on a much larger scale which I have made; for on augmenting the size of the machine you augment the size of the revolving shaft and its magnets ; friction increases conse- [* See Pbil, Mag., First Series, vol, Ixvi. p. 98.~Edit.] k Mr. Wotkins on EledrO'tnagnetic motive Machines, 195 quently in a very rapid proportion, while the space gained through whicii the magnetic attractive force operates is in- creased comparatively in a very small degree. It is truly surprising how limited is the ratio of improve- ment in the power of a machine by enlarging its magnets, as we then unfortunately increase the weight of the moving parts. I have noticed before, that the model with one pair of steel magnets, with four arms, and one electro-magnet, raised a weight through a certain space in a given time. Now when the model with two pair of steel magnets with four arms and two electro-magnets was experimented with, it was found that the latter was not so much more powerful than the former as we might have been led to expect. It should be remembered that the means employed to change the direction of the current and the weight of the axis or shaft in both cases were exactly alike ; therefore I conceive it was the extra friction of the axis caused by the extra weight of the additional pair of steel magnets that decreased the inertia of motion, and thus prevented the available power increasing to the amount anticipated. I have not remarked upon the resistance of the air to the revolving arms, for that must be a retarding action in all cases of revolution. Besides the arms cut the air edgewise, there- fore they are under the most favourable circumstances as re- gards that point. It has been suggested as the means of gaining more power o multiply the number of fixed and moveable magnets, and so contrive that the forces should conspire to produce their sum at the working point, and we may infer that an advantage to a certain degree may be gained by a skilful arrangement ; but if my views are correct, the power gained could be ob- tained on a large scale from other sources more oeconomically. I am well aware it frequently occurs in the application of a philosophical principle or a mechanical arrangement that there is a considerable difference between a model and that of a large working machine ; it therefore behoves all persons experimen- tally engaged in the application of a principle or a power to bear this in mind, and not to decide too hastily because they fail several times with models. And I am also aware that my arrangement is faulty, and not the most judicious that could be contrived, although one of them is very simple ; yet it does appear from the nature of the force we employ, and its small distance of working action, that we must look forward and hope for a better knowledge of the nature of the mysteri- ous and invisible agent which is to actuate our machines before complete success crown our endeavours, Z2 196 C. H. Matteucci's Researches relative to the Torpedo^ Human perseverance has achieved wonders ; and as the subject engrosses considerable attention just uovf, and v^^e rejoice to find by the periodicals that the Emperor of Russia has placed at the disposal of M. Jacobi and a scientific com- mittee 500/. for the purpose of making experiments, we may indulge in the hope that before long some successful results will be the fruits of their labours, and that a new method of employing magnetism will be discovered ; for from the present mode, if my notions be correct, we have little to hope for on a large scale, and playdiings are not worth the mechanician's notice. I remain, Gentlemen, yours, &c., Francis Watkins. XXVIII. Physical, Chemical, and Physiological Researches re- lative to the Torpedo ; and some Remarks on the Contractions of the Frog, By C. H. Matteucci {read before the Prench Academy by M. Becquerel)*. IVf MATTEUCCI has presented to the Academy a Me- -'-*-*■• moir on the electrical phaenomena of the torpedo, as also several notes relative to the contractions produced in the frog by the contact of the muscles with the nerves. These having been submitted to the examination of a committee composed of MM. Breschet and Pouillet and of myself, we have the honour of laying before you an account of these va- rious researches. The sensation which the torpedo causes when it is touched has long ago attracted the attention of physicists and physio- logists, on account of its analogy with that produced by an electrical battery, but it is only a few years since that it has been decidedly proved that both were owing to the same cause. Although all the principal circumstances of this phaenomenon had previously been carefully studied, yet no one had succeeded in demonstrating its electrical origin from the want of suitable apparatus. John Davy made known in a paper published in 1832 a great number of important data, such as the action of the dis- charge upon the magnet needle, and the chemical compounds; but the direction of the electrical current produced on this occasion was not well known until after the experiments made at Venice, 1835, by two of your members, and from which it resulted that the superior part of the electrical organ gives positive electricity, and the inferior part negative electricity. Matteucci has confirmed with the galvanometer and frogs * Translated by Mr. Francis from the Comptes Kendus, No, S3, Dec. 1837. a7id Remarks on the Contractions of the Frog. 197 prepared after the method of Galvani the observations which we had made respecting this point, as well as others also re- lating to the torpedo, for which we are indebted to various philosophers; at the same time he has demonstrated some new facts, of which the following is a short account. He commences by showing that when the torpedo lances its discharge no change of volume is observed in its body. When the animal is possessed of great liveliness the sensation is felt at whatever point of the body it may be touched, but when its vitality is considerably diminished the discharge is no longer felt, except by touching the electrical organs at two different points. Matteucci establishes the general laws of the distribution of electricity in this manner: — 1. All the points of the dorsal part of the organ are positive relatively to the points of the ventral part; a fact already known. 2. The points of the organ on the dorsal surface placed above the nerves which enter it are positive in respect to the other points of the same dorsal surface. 3. The points of the organ situated on the ventral surface corresponding to the points which are positive on the dorsal surface are negative in respect to the other points of the ventral surface. 4. The intensity of the current varies with the extent of the platina plates which terminate the galvanometer, and with which the two surfaces of the organ are touched. When the torpedo is very excitable the current may be compared to that of a pile consisting of a great number of pairs charged with a good conducting active liquid ; whilst, on the other hand, when its liveliness is weak, the electric current resembles that of a pile composed of a small number of elements. The spark which accompanies the discharge in the electri- cal fishes was remarked for the first time by Walsch in the Gymnotus; many vain efforts have been made since to repro- duce it; MM. Matteucci and Linari have succeeded in ob- taining it in every case from the torpedo ; both these philoso- phers claim the priority of the observation. It appears from the notices which we have gathered that Matteucci was the first who had the idea of employing for this purpose Faraday's apparatus of the extra current, which M. Linari did not make use of until after it had been pointed out to him by his countryman. Matteucci has since succeeded in obtaining the spark by placing the torpedo upon an isolated plate of metal, and pla- cing another plate of metal above it, then fixing to each of them a gold leaf separated the one from the other by the distance 198 C. H. Matteucci*s Researches relative to the Torpedo^ of half a millimetre. By slightly moving the upper metallic plate the animal became irritated, and at the same moment the two leaves approached one another and the report of the spark was instantly heard. Matteucci has carefully studied the internal and external causes which influence the discharge of the torpedo ; among the external causes we may distinguish, besides the mechani- cal excitement, heat, in water at 18° Reau. The torpedo seldom lives more than five or six hours, preserving all its electrical power ; on diminishing the temperature this power instantly ceases. On heating the water the discharges begin afresh, but if the temperature is increased to + 30° Reau., as we ourselves also observed, the animal after several dis- charges suffers violent contractions and dies in a sort of te- tanic state. Matteucci having analysed the air contained in sea-water, has determined the variations which result from this with re- spect to the respiration of the torpedo. According to the ob- servations which he has made relative to this point, when the torpedo is tormented it respires more than that which is not ; and what is most singular, if the fact be true, is that the for- mer produces under the same circumstances less carbonic acid than the other : it would seem in general that the intensity of the electric function is in proportion to the force of the circu- lation and of the respiration. The action of the most energetic poisons produce the fol- lowing effects : — Hydro-chlorate of strychnia introduced into the mouth and stomach of a torpedo produced almost imme- diately violent contractions in the vertebral column accompa- nied with powerful discharges, afterwards of weaker discharges, and the animal expires in violent convulsions. Hydro-chlorate of morphine produces in eight or ten minutes after its intro- duction into the animal very powerful discharges; it some- times gives more than sixty discharges in ten minutes. The current of an electrical apparatus composed of eight pairs directed from the mouth to the branchiae, and to the epider- mis of the interior of the organ, produces strong discharges. Electricity acts in this case probably only as a violent excitative. Matteucci having cut the half of the organ either in a hori- zontal or in a vertical direction, and having placed between the divided parts a plate of glass, the discharge still took place; this was the case also even when the organ held to the ani- mal only by a nervous fibre : the effects did not cease before the substance of the organ became coagulated by the action of the acids or of the boiling water. We may remark with respect to this, that several philosophers, and especially Gal- and Remarks on the Contractions of the Frog, 199 vani, have made similar experiments ; they found, for instance, that if the four nerves of one of the organs are severed, the discharge immediately ceases in this organ, while it manifests itself continually in the other ; and that if only two or three nerves are cut, the sensation is limited to points corresponding to the nerves which have remained intact: they concluded from their observations that the brain and the nervous trunks exercise an influence which determines the electrical faculty of the torpedo. Matteucci has arrived at the same conclusions, but he has determined better than any one had done before him the extent of this influence, as will be seen. If we tie the nerves, the same effects are produced as on cutting them. When the nerves have been severed, if one of the nervous trunks which branches in the organ is drawn forth with pincers, we still obtain some discharges. If the brain is laid open, and certain parts be irritated with any body whatsoever, the discharge is instantly evident. The first lobes (the cerebral) may be irritated, severed, and even destroyed without the dis- charge disappearing; the same is the case with the third lobe. As to the fourth, it may be touched without producing power- ful discharges ; on destroying it, even when the others are left whole, the electrical power of the animal is entirely de- stroyed. This observation, which is very remarkable, will certainly be of great interest to physiologists on account of its singularity. When the animal is in such a state of torpidity as not to give any more discharges, when the ordinary excitatives are employed, if we then lay open the brain and touch the elec- trical lobe, the discharges appear with force going indifferently from the back to the belly, and from the belly to the back, whilst no effect is produced on irritating the other parts of the brain ; if we employ electricity as the excitative we obtain a similar result. We think it our duty to mention in this place that M. Flourens had already proved by direct experiments, published in 1825, that the last lobe of the brain is in fish in general the special encephalic organ of respiration. If one side of this lobe is cut away, the movement of the operculum of this side is immediately destroyed ; the movement of the operculum of the opposite side continues. If the lobe be entirely taken away, the play of the two opercula ceases suddenly. Flourens more- over proved that the action of the last lobe (of the lobe situ- ated behind the cerebellum of the brain) upon the opercula continues complete after the taking away of all the other parts of the encephalus, as after the taking away of the spinal mar- row, whether these two removals (that of all the other parts of 200 C. H. Matteucci's ResearcJies relative to the Torpedo^ the encepbalus, and that of the spinal marrow) be made sepa- rately or simultaneously. M. Matteucci having entirely separated from a great tor- pedo one of the electrical organs, without detaching the epi- dermis, one of the plates of the galvanometer was inserted in the organ near the outward edge, the other plate was put in communication with one of the four nerves : the needle devi- ated four degrees in the common direction of the discharge of the torpedo; on tying the nerves there was no longer any deviation ; this result appears to us very remarkable. The above observations, which we have not been able to confirm from the wantof torpedos,goto prove, 1, that the elec- tricity which produces the discharge proceeds from the last lobe of the brain, and is transmitted by the nerves to the or- gan ; 2, that the discharge ceasing under the influence of the electric current, when the nerves are tied, must, in order to be transmitted, find in the nerve a particular molecular dis- position ; a conclusion to which the electro-physiological phaenomena of the frog equally lead, as one of us (M. Bec- querel) has indicated in various places in his treatise on elec- tricity. Since the ever-memorable epoch when Gal vani demonstrated that the contact of two different metals in communication with the muscles and nerves of a frog sufficed to make it contract, the experiments have been varied infinitely in the hope to discover in this phagnomenon the cause which constitutes life in animated bodies. The most remarkable fact, for which we are also indebted to Galvani, is that which relates to the con- tractions produced by the simple contact of the muscles and nerves without the intermediary of metallic armatures. It is now nearly demonstrated that this action does not proceed from a chemical action, but from the inherent current of the frog, which has been indicated with so much sagacity by M. Nobili. On the other hand, Ritter and several other philosophers* have remarked that the irritability in those parts which are separated from the body of the frog does not at the same time cease in the entire course of the nerve; it begins by leaving off* at those parts nearest to the brain and ends by those which are most distant. Miiller moreover maintains that a nerve tied oY compressed ceases to be a conductor of the agent which circulates in the nerves, whichever it be; it re- mains nevertheless a good conductor of electricity. Matteucci noticed a similar fact in the torpedo, as we have remarked ; • MUller's Manual of Physiology, p. 603. and Remarks on the Contractions of the Frog, 20 1 but it is chiefly on the frog that these observations afford with respect to this great interest. Wlien the nerve is tied, a sim- ple electro-chemical current passes through the ligature and ceases to cause the frog to contract much sooner than its own current ceases to act ; the ligature does not in the least alter the conductibility of the current, however feeble it may be. In the living animal when the muscles are brought into con- tact with the nerves, the contractions are more feeble than those produced by the inherent current of the frog after death ; the contractions grow weaker and discontinue when the parts have been well wiped ; and if the animal remains still, the current generally ceases to take place. If we place the frog between two pieces of glass for ten to twelve seconds, and then withdraw it, the inherent current no longer exists. On introducing oxygen into the mouth the animal instandy becomes agitated, jumps, and the peculiar current re-appears, and then vanishes, as Matteucci has ob- served in the torpedo. When the thighs and crural nerves brought into contact no longer produce any contraction, if the nerves near to the spinal marrow are then cut, and if touched immediately with the thighs, contractions immediately take place. When all sign of the inherent current has disappeared, if we draw forth the sciatical nerve of the thigh and bend it on the mus- cles of the leg or of the other thigh, the thigh corresponding to the nerve touched will become contracted ; this latter fact belongs to the law indicated by Ritter, which this physicist had remarked with the help of an electric current. These observations go to prove, as has been admitted by several philosophers, that there exists an electric current con- tinually circulating in the nerves and in the muscles of the living frog, by means of a complete arc, which can only be rendered perceptible by our apparatus when the animal is in a state of excessive excitation; whilst by preparing the frog after the manner of Galvani the integrity of the arc is destroyed and we easily recognise the inherent current. The facts we have thus laid before the Academy, and of which many have been verified by us, throw some light on the electro-physiological phaenomena of the torpedo and frog, and will not fail to interest the Academy. We therefore pro- pose that the several communications of M. Matteucci be in- serted in the Becueil des Savans Etrangers*, * This was agreed to after a long discussion respecting the question of priority between Matteucci and Linari as to the production of the spark. See p. 197. Our readers are referred to an interesting notice connected with the subject of this paper in page 223. — W. F. [ 202 ] XXIX. Notices respecting New Booh, A Practical Treatise on Warming Buildings hy Hot Watery tvith some remarks on Ventilation. By Charles Hood, Esq., F.Il.A.S., illus- trated by numerous Wood-cuts, 8vo. London, 1837. This is a practical and scientific treatise on an important subject, which is every day attracting more and more public attention. The inquiry is pursued in a popular manner, in order to render it intelli- gible to all readers j all abstruse calculations and scientific techni- calities have been avoided as much as possible. The merits of the various kinds of apparatus employed are carefully considered, their philosophical principles pointed out, and their utility displayed in a practical manner, and illustrated by well-executed diagrams. One of the most important chapters is that on ventilation, showing the deleterious efiects upon the human frame of atmospheric air which has been changed by the process of respiration, or by subjection to the action of heat, or in any other way; and the necessity of suffi- cient and good ventilation. " It has been proved by experiments," says the author, p. 173, *' that air which has been once inhaled loses about 10 per cent, of its oxygen, or nearly one half that it contains, and acquires from 8 to 8^^ per cent, of carbonic acid gas. This gas, it is well known, is as destructive to animal life as the oxy- gen is necessary for its preservation, and, therefore, air cannot be breathed a second time without serious inconvenience. For, as it is found impossible to make atmospheric air contain more than 10 per cent, of carbonic acid gas, it follows, that, if breathing a quantity of air once impregnates it with 8i per cent, of this gas, if it be breathed a second time, it can only receive H per cent. ; and there- fore the remainder must be left in the lungs, where it exerts a most deleterious effect. The noxious qualities of this gas are well known ; the foul air of wells, which causes death in so many instances, con- sists of this deleterious matter ; and it is extraordinary that the heart and muscles of any animal that has been deprived of life by breathing it, entirely lose their irritability, and become insensible even to the powerful stimulus of galvanism." We have great plea- sure in recommending this work to the attention of the public in general. A Guide to an Arrangement of British Insects. By J. Curtis, Esq., F.L.S., Author of British Entomology, 2nd edit., 8vo. London, 1837. In order to remedy the great inconvenience which students in Entomology must have experienced of not having a compact printed Catalogue of British Insects, Mr. Curtis has published this useful work, with a view to enable them to arrange their cabinets systematically ; to mark oft' their own insects so as to know instantly whether they have a species or not, by which means their desiderata will be shown, and they will be enabled to enrich their cabinets by mutual exchanges ; to form labels for cabinets, and save much time that would be required for writing them. It is also a systema- Bibliographical Bulletin, 203 tic index to Mr. Cuitis's British Entomology, a reference being given to every genus illustrated in that valuable and splendid work, which now contains more than 700 beautiful and accurate coloured repre- sentations of insects, and nearly as many of indigenous plants. The numerous additions that have been made to our British collections of late having been embodied in the present edition, it is far the most complete catalogue of the present day, comprising nearly 15,000 British species, and cannot fail to be highly serviceable to those for whose use it is designed. Bibliographical Bulletin. Poggendorff's Annalen, 1837, Nos. 8 and 9. Contents.— On the nature of uric acid ; by Liebig and Wohler. — Jervin, a new vegetable basis ; by E. Simon. (See for a translation of this paper pres. vol. p. 29.) — On oenanthic acid and oenanthic acid aether ; by Liebig and Pelouze.— On the oil in liquors distilled from grain ; by G. J. Mulder.— New preparation of chrome alum ; by F. Marchand.— -On the aether sul- phates; by the same.— Detection of sulphuric acid in cases of medical jurisprudence; by J. Simon.— Occurrence of arsenical copper in Chili; by Zinkem. — Observations on the influence of crystalline surfaces on reflected light ; by F. E. Neumann. — On Becquerel's simple series, whose current is said to originate from the combination of acids and alkalies ; by F. Mohr. (We hope to be able to give a translation of this paper in our next number.) — On the production of electricity in chemical combinations ; by P. Dulk. — Method of separating the oxides of cobalt and nickel, as also the protoxide of manganese, from the oxide of iron and from arsenic and arsenious acid ; by Th. Scheerer. — On the simple and double Ajan metals; by Rammelsberg, — On a series of organic combinations which contain arsenic as a constituent; by Bunsen. — Paton, Marsh, and Simon's methods of detecting arsenic, with remarks by Berzelius. — Reduction of sulphuretted arsenic by means of sil- vered carbon ; by F. Runge. — On the combination of azote with metals, for instance with copper when in a state of red heat ; by PfafF. Neue Notizen von Froriep, vol. iii. Contents. — No. 2. Magnets without cohesion. — Experiments on the pro- cess of respiration ; by Th. Bischof. — No. 3. Further microscopical obser- vations on the primitive fibres of the nervous system of the Vertebrata ; by R. Remak. — No. 4. Natural classification of polypi. — No. 5. On the blood and lymph globules ; by Prof. Mayer in Bonn.— No. 8. On some parasitical animals and organic products of the common rain worm. Journal fur praktische Chemie. By 0. L. Erdman, Part 7 — 10. Contents. — Description of two new minerals from Siberia ; by Aug. Breil- haupt. — On the alkaline reaction of various carbonate salts. — Analysis of Agalmatolite. — On the fabrication of straw paper ; by Piette. — On the application of the pith of the mangel wurzel to the fabrication of paper. — Description of some new minerals; by Breithaupt. — Method of preparing Atropia and Atropic acid ; by W. Richter. — Action of animal charcoal on salts of iron. Flora. No. 25, etc.. 1837. Contents. — On the symmetry of plants ; by H. Mohl. — On the generic characters of trees ; by G. Liegbl. — Plantaj qusdam novaj vel minus cog- nitae in .Egypto a cl. Acerbi, in Nubia a eel. Brocchi cletectae.— Martins, Herbarium Florie Brasiliensis. [ 204^ ] XXX. Proceedings of Learned Societies* ROYAL SOCIETY. [Continued from vol. xi. p. 196.] Nov. 16, *' "TAESCRIPTION of a new Barometer, recently fixed 1837. -^-^ up in the Apartments of the Royal Society ; with remarks on the mode hitherto pursued at various periods, and an account of that which is now adopted, for correcting the observed height of the mercury in the Society's Barometers." By Francis Baily, Esq., Vice-President and Treasurer, R.S. The barometer, here alluded to, may in some measure be consi- dered as two separate and independent barometers, inasmuch as it is formed of two distinct tubes dipping into one and the same cistern of mercury. One of these tubes is made of fiint glass, and the other of crown glass, with a view to ascertain whether, at the end of any given period, the one may have had any greater chemical effect on the mercury than the other, and thus affected the results. A brass rod, to which the scale is attached, passes through the framework, between the two tubes, and is thus common to both : one end of which is furnished with a fine agate point, which, by means of a rack and pinion moving the whole rod, may be brought just to touch the surface of the mercury in the cistern, the slightest contact with which is immediately discernible ; and the other end of which bears the usual scale of inches, tenths, &c. ; and there is a separate vernier for each tube. A small thermometer, the bulb of which dips into the mercury in the cistern, is inserted at the bottom : and an eye- piece is also there fixed, so that the agate point can be viewed with more distinctness and accuracy. The whole instrument is made to turn round in azimuth, in order to verify the perpendicularity of the tubes and the scale. It is evident that there are many advantages attending this mode of construction, which are not to be found in the barometers as usu- ally formed for general use in this country. The absolute heights are more correctly and more satisfactorily determined ; and the per- manency of true action is more effectually noticed and secured. For, every part is under the inspection and control of the observer ; and any derangement or imperfection in either of the tubes is imme- diately detected on comparison with the other. And, considering the care that has been taken in filling the tubes, and setting off the scale, it may justly be considered as a standard barometer. The pre- sent volume of the Philosophical Transactions will contain the first register of the observations that have been made with this instru- ment. Mr. Baily then enters into a description of the several corrections that are required for the various kinds of barometers, in order t6 make them comparable with one another ; and treats of each of these in their order. First as to the correction for temperature, both of the mercury and of the scale ; next for capillarity ; and afterwards for the height of the barometer above the level of the sea. A table Mr. Daily on a New Barometer, 905 is given for the first of these corrections ; and a convenient formula for the latter : the correction for capillarity is constant, and of very small magnitude. The author next describes the mode in which the observations of the barometer have, from time to time, been recorded in the Meteor- ological Journal of this Society ; and points out several inaccu- racies which have occasionally been committed in this depart- ment, for want of an uniform plan of reduction. Now this state of confusion and uncertainty he remarks ought not to exist in a me- teorological journal emanating from this Society, more especially as the true values are as easily attainable as the approximate ones. And although, in a general point of view, the minute differences caused by such errors may be unimportant, yet as appeals are fre- quently made to the barometer of this Society, as a standard, by persons engaged in important researches, the most scrupulous accu- racy ought to be adopted and pursued, and the fullest explanation placed on record. And Mr. Baily says that notwithstanding the de- tails which he has given may create some doubt respecting the ac- curacy of the past, yet he is persuaded that the system now pursued will inspire more confidence for the future. It is on this account that he has entered thus at large on the subject ; trusting that what he has stated will not only tend to preserve for the future a more correct and uniform system, but also justify the Council in directing that the register should henceforth contain the daily observations uncorrected, and thus prevent the possibility of any similar confusion and mistakes hereafter. Mr. Baily then adverts to the height of the Society's barometer above the mean level of the sea ; a subject of much interest to many persons engaged in various pursuits, but which appears, from the notes attached, at different periods, to the meteorological journal of this Society, to be involved in some confusion and uncertainty. Thus, prior to the year 1823, the cistern of the barometer is said to be 81 feet above the level of low- water spring tides at Somerset House ; but without any information how this was connected with the sea. From 1823 to 1825, both inclusive, it is said to be 100 feet above the same level. And from 1826 to 1836, both inclusive, the above indication is omitted, and the height is said to be 83 feet 2^ inches above a fixed mark on Waterloo Bridge ; or " above the mean level of the sea (presumed about) 95 feet." The discordance between the 81 feet and the 100 feet is easily accounted for by the fact that the old barometer, prior to 1823, was fixed up in the Council-room of the Society, or the contiguous ante-room : but when Mr. DanieU's barometer was finished, at the end of the year 1822, it was fixed up in the closet adjoining the library, on the floor which is immediately over the Council-room ; the assumed difference in the elevation of the two floors (namely, 19 feet) having since been ascertained to be correct. With respect to the new reference of altitude, namely, the fixed mark at Waterloo Bridge, much doubt has frequently been expressed about its existence, since no person had been able to discover it. The fact is that there is no mark, in the common acceptation of the 20G RoTjal Society : — Prof. Faraday's Experimental term ; but the intended reference is nevertheless more conspicuous, more durable, and more convenient than any mark that could have been inscribed by hands. This standard mark, or level, was fixed on by Mr. Bevan in the year 1827, at the request of the Council of this Society : and it is the surface of the granite pedestal at the base of the columns, at the north abutment of the bridge, and on the eastern side ; which is about 5 feet above the lowest platform, or landing, at the stairs. Nothing therefore was wanting but the dif- ference of level between this mark and the one made by Capt. Lloyd at London Bridge, the height of which above the mean level of the sea had been determined by him*. This has been recently done by Sir John Ilennie, at the request also of the Council : and the result of the whole is, that the cistern of the barometer is 97 feet above ^he mean level of the sea. The author concludes his paper with some remarks on the pro- priety of the position of the several meteorological instruments of the Society. With respect to the barometer, he says he is not aware that any objection can be offered ; and as to the hygrometer, the ob- servations have been found, by recent trials, not to differ materially from some expressly made in another position, at King's College, which was considered to be more favourable for such experiments. It therefore only remains to speak of the external thermometer and of the rain-gauge ; of which all that can be said on the subject would be merely a repetition of what was justly said sixty years ago by Mr. Cavendish on a similar occasion (Philosophical Transactions, 1776), namely, " that, on the whole, the situation is not altogether such as could be wished, but is the best the house affords.'* Nov. 23. — "Magnetical Observations made in the "West Indies, on the Coasts of Brazil and North America, in the years 1834, 1835, 1836 and 1837." By Sir James Everard Home, Bart., Com- mander Royal Navy, F.R.S,, the Observations reduced by the Kev. George Fisher, M.A., F.R.S. The observations for the dip were made with an instrument of modern construction, by DoUond. Each observation consisted of an equal number of readings of the position of the needle, before and after the inversion of its poles, and a mean of all the readings taken for the true dip. Tables are subjoined, containing the dips ob- served at each place ; the times of making a hundred vibrations of five horizontal needles, and the mean horizontal forces computed therefrom ; and likewise the results estimated in the direction of the dipping needle, compared with direct experiments made with the dipping needle itself. A paper was also read in part, entitled " On Low Fogs and Sta- tionary Clouds." By William Kelly, M.D. Communicated by Capt. Beaufort, R.N., F.R.S.f Jan. 11, 1838. — The reading of a paper, entitled " Experimental Researches in Electricity," Eleventh Series, by Michael Faraday * See Phil. Mag. and Annals, vol. ix. p. 357; and Lond. and Edinb. Phil. Mag., vol. i. p. 187. + An account of the Anniversary Proceedings of the Royal Society, and of the p&perg read at the meetings prior to January 11, will appear in our next. Researches in Electricity : Eleventh Series, 207 Esq.,D.C.L., F.R.S., FuUerian Professor of Chemistry at the Royal Institution, &c., was resumed and concluded. The object of this paper is to establish two general principles re- lating to the theory of electricity, which appear to be of great im- portance ; first, that induction is in all cases the result of the actions of contiguous particles ; and secondly, that different insulators have different inductive capacities. The class of phenomena usually arranged under the head of in- duction are reducible to a general fact, the existence of which we may recognise in all electrical phaenomena whatsoever ; and they involve the operation of a principle having all the characters of a first, essen- tial and fundamental law. The discovery which he had already made of the law by which electrolytes refuse to yield their elements to a current when in the solid state, though they give them forth freely when liquid, suggested to the author the extension of analogous ex- planations with regard to inductive action, and the possible reduction of many dissimilar phaenomena to one single comprehensive law. As the whole effect upon the electrolyte appeared to be an action of the particles when thrown into a peculiar polarized state, he was led to suspect that common induction itself is in all cases an action of contiguous particles, and that electrical action at a distance, which is what is meant by the term induction, never occurs except through the intermediate agency of intervening matter. He considered that a test of the correctness of his views might be obtained by tracing the course of inductive action ; for if it were found to be exerted in curved lines it would naturally indicate the action of contiguous particles, and would scarcely be compatible with action at a distance. More- over, if induction be an action of contiguous particles, and likewise the first step in electrolyzation, there seemed reason to expect some particular relation of this action to the different kinds of matter through which it was exerted ; that is, something equivalent to a specific electric induction for different bodies ; and the existence of such specific powers would be an irrefragable proof of the dependence of induction on the intervening particles. The failure of all attempts to produce an absolute charge of electricity of one species alone, in- dependent of the other, first impressed on the author the conviction that induction is the result of actions among the individual and con- tiguous particles of matter, having both forces developed to an ex- tent exactly equal in each particle. The author describes various experiments, with the view of show- ing that no case ever occurs in which an absolute charge of one spe- cies of electricity can be given. His first experiments were conducted on a very large scale : an insulated tube, twelve feet in the side, consisting of a wooden frame, with wire net- work, every part of which was brought into good metallic contact by bands of tin foil, had a glass tube, containing a wire in connexion with a large elec- trical machine, passed through its side, so that about four feet of the tube entered within the cube and two feet remained without ; but it was found impossible in any way within this apparatus to charge the ftir with the least portioa of either electricity. 208 Royal Society*, — Prof. Faraday's Experimental For investigating the question whether induction is an action of contiguous particles, and for deciding that of specific inductive capa- city, the author employed, in conjunction with the torsion balance of Coulomb with certain variations and additions (such as an electro- meter), a new apparatus, constructed for the express purpose. This apparatus consisted of two hollow brass spheres, of very unequal diameters, the smaller placed within the larger and concentric with it ; the interval between the two being the space through which the induction was to be effected. The apparatus had a tube in the lower part, furnished with a stop-cock, by means of which it might be con- nected with an air-pump or filled with any required gas. In place of the lower hemispherical shell of air, occupying the interval be- tween the two spheres, any solid dielectric, of the same form, such as shell-lac, glass, or sulphur, might be substituted. Two of these instruments, precisely similar in every respect, were constructed, and the author ascertained that the inductive power was the same in both by alternately charging each and dividing the charge with the other, and finding that, in all cases, the charge remaining in the one, and also that received by the other, was very nearly half the original charge. The experiments on which the author principally relies, in support of the correctness of his views relative to induction being exerted in curved lines, are the following : a brass ball being laid on the top of an excited cylinder of shell-lac placed perpendicularly, the charge which a carrier ball received when brought to different points near to the brass sphere was measured by means of the electrometer, and it was inferred, from the characters of the electricity, that the charge was one by induction, and from its measure, that it proceeded in curved lines. By substituting for the brass sphere a disc of metal, above the shell-lac cylinder, it was found that when the carrier ball was brought near to the middle of the disc no charge was communicated, although a sensible one was obtained at the edge of the disc, and also at a point above its centre, further removed from the excited cylinder. Corresponding and very striking results were obtained when a brass hemisphere was placed on the top of the cylinder of lac. The charge communicated at the centre of the hemisphere was only one third of that obtained at the edge of its periphery ; but by taking it at a point at some height above the centre, and consequently much further removed from the inducing cause, the charge was nearly equal to that of the periphery. Here, the author remarks, the in- duction fairly turned a corner, exhibiting both the curved lines or courses of its action, when disturbed from their rectilineal form by the shape, position and condition of the metallic hemisphere ; and also a lateral tension, so to speak, of these lines on one another ; all depending on induction being an action of the contiguous particles of the dielectric thrown into a state of polarity and tension, and mu- tually related by their forces in all directions. In the foregoing ex- periments the dielectric was air, but they were afterwards varied by substituting a fluid, as oil of turpentine, and likewise a few solid dielectrics, namely, shell-lac, sulphur, carbonate and borate of lead, Researches in Electricity : Eleventh Series, 209 flint-glass, and spermaceti, and with these, corresponding results were obtained. These results, the author considers, cannot but be admitted as arguments against the received theory of induction, and in favour of that which he has put forth. In the course of these experimental researches, some effects due to conduction, which had not been anticipated, and which were si- milar to the residual charge in the Leyden jar, had been obtained with such bodies as glass, lac, sulphur, &c. If the inductive appa- ratus, fitted with a hemispherical cup of shell-lac, after having re- mained charged for fifteen or twenty minutes, was suddenly and per- fectly discharged, and then left to itself, it would gradually recover every sensible charge ; the electricity which thus returned from an apparently latent to a sensible state being always of the same kind as that given by the charge. This return charge is attributed to an actual penetration by conduction of the charge to some distance within the dielectric at each of its two surfaces, and several experi- ments are adduced in support of this view. With shell-lac and sper- maceti the return charge was considerable ; with glass and sulphur it was much less ; but with air, no decided effect of the kind could be obtained. As this was an effect which might interfere with the results, in the method the author adopted for deciding the question of specific inductive capacity, and as time was requisite for this pe- netration of the charge, its influence on these results was guarded against, by allowing, between the successive operations, as little time as possible for this peculiar action to arise. The author thus states the question of specific inductive capacity which he had proposed to investigate : — I suppose A an electrified plate of metal suspended in the air, and B and C two exactly similar plates, placed parallel to and on each side of A, at equal distances, and un-insulated, A will then induce equally towards B and C. If in this position of the plates, some other dielectric than air, as shell- lac, be introduced between A and C, will the induction between them remain the same ; or will the relation of C and B to A be altered by the difference of the dielectrics interposed between them ? The experiments of Coulomb, from which it appeared that a wire surrounded by shell-lac took exactly the same quantity of electricity from a charged body, as the same body took in air, seemed to the author to be no proof of the truth of the assumption, that, under such variation of the circumstances as he had supposed, no change would occur. Entertaining these doubts of the conclusions deduci- ble from Coulomb's result, he had the apparatus previously described constructed, as being well adapted for this investigation. After re- jecting glass, resin, wax, naphtha, oil of turpentine, and other sub- stances, as unfit for the purpose in view, he chose shell-lac as the substance best calculated to serve as an experimental test of the question. For the purpose of comparing the inductive capacities of shell-lac and air, a hemispherical cup of shell-lac was introduced into the lower hemisphere of one of the inductive apparatus, so as to nearly fill the lower half of the space between the two spheres ; and their charges Phil. Mag, S. 3. Vol. 12. No. 73. Feb, 1838. 2 A 210 "Royal Society, were divided in the manner already described ; each apparatus being used in turn to receive the first charge, before its division with the other. As the two instruments were known to have equal inductive powers when air was contained in both, any deficiencies resulting from the introduction of the shell-lac would show a peculiar action in it, and if unequivocally referable to a specific inductive influence, would establish the point in question. The air apparatus being charged, and its disposable charge being 290°, this charge was divided between the two. After the division the charge in the lac apparatus was IIS'^, and in the air apparatus 11 4^^. From this it appears that whilst by the division the induction through the air lost 11 Q°, that through lac gained only 113°. As- suming that this diflference depends entirely on the greater facility possessed by shell-lac of allowing or causing inductive action through its substance than that possessed by air, then the capacity for electric induction would be inversely as the respective loss and gain ; and as- suming the capacity of the air apparatus as unity, that of the shell- lac apparatus would be yro or 1*55. When the shell-lac apparatus was first charged, and then the charge divided with the air apparatus, it appeared that the lac appa- ratus, in communicating a charge of 118°, only lost a charge of 86°. This result gives 1-37 as the capacity of the lac apparatus. Both these results, the author considers, require a correction ; the former being in excess, the latter in defect. Applying this cor- rection, they become 1*50 and 1-47. From a mean of these and se- veral similar experiments, it is inferred that the inductive capacity of the apparatus having the hemisphere of lac is to that with air as 1-50 to 1. As the lac only occupied one half of the apparatus containing it, the other half being filled with air, it would follow from the foregoing result, that the inductive capacity of shell-lac is to that of air as 2tol. From all these experiments and from the constancy of their results the author deems the conclusion iiTesistible, that shell-lac does ex- hibit a case of specific inductive capacity. Similar experiments with flint-glass gave its capacity 1-76 times that of air. Using in like manner a hemisphere of sulpliur, it appeared that the inductive capacity of that substance was rather above 2*24 times that of air, and the author considers this result with sulphur as one of the most unexceptionable. With liquids, as oil of turpentine and naphtha, although the re- sults are not inconsistent with the belief, that these liquids have a greater specific inductive capacity than air, yet the author does not consider the proofs as perfectly conclusive. A most interesting class of substances, in relation to specific in- ductive capacity, the gases or aeriform bodies, next came under the author's review. With atmospheric air, and likewise with pure oxygen, change of deasity was found to occasion no change in the inductive capacity. Zoological Society, 211 Nor was any change produced, either by an increase of temperature or by a variation in the hydrometric state. The details are then given of a very elaborate series of experiments with atmospheric air, oxygen, hydrogen, nitrogen, muriatic acid, carbonic acid, sulphurous acid, sulphuretted hydrogen, and other gases, undertaken with the view of comparing one with another under a great variety of modifications. In conclusion, the author remarks, •* Thus induction appears to be essentially an action of contiguous particles, through the interme- diation of which the electric force originating or appearing at a cer- tain place, is propagated to or sustained at a distance, appearing there as a force of the same kind and exactly equal in amount, but oppo- site in its direction and tendencies. Induction requires no sensible thickness in the conductors which may be used to limit its extent, for anun-insulated leaf of gold may be made very highly positive on one surface, and as highly negative on the other while the induction con- tinues without the least interference of the two states. But with regard to dielectrics, or insulating media, the results are very differ- ent ; for their thickness has an immediate and important influence on the degree of induction. As to their quality, though all gases and vapours are alike, whatever be their state, amongst solid bodies, and between them and gases, there are differences which prove the existence of specific inductive capacities." The author also refers to a transverse force with which the direct inductive force is accompanied. The experimental proof of the ex- istence of such a force, in all cases of induction, is, from its bearing on the phsenomena of electro-magnetism and magneto -electricity, of the highest importance, and we cannot but look forward with the greatest interest to the promised communication in which these and other phsenomena relating to this subject will be reviewed. ZOOLOGICAL SOCIETY. [Continued from vol. xi. p. 474.] January 10, 1837. — A paper was read, entitled " Observations on the Phosphorescence of the Ocean, made during a voyage from England to Sydney, N.S. Wales.'* By George Bennett, Esq., F.L.S., Corresp. Member of the Society. The author commences this paper with adverting to the very slight progress which naturalists have made in their attempts to elucidate the history of the phsenomena connected with the phosphorescence of the ocean, and notices some of the imaginary advantages which former observers have attributed to its presence ; among others that of its indicating to mariners the existence of shoals and soundings, a circumstance which his own experience has not enabled him to confirm. He then proceeds to remark, that the sea, when phospho- rescent, exhibits two distinct kinds of luminosity, one in which its surface appears studded with scintillations of the most vivid descrip- tion, more particularly apparent as the waves are broken by the vio- lence of the wind or by the passage of the ship through them, as though they were electric sparks produced by the collision, and which 2A2 '212 Zoological Society, scintillations he considers are probably influenced, in some measure, by an electric condition of the atmosphere, as at those particular times they were observed to be much more vivid and incessant than at others. The other kind of luminosity spoken of has more the appearance of sheets or trains of whitish or greenish light, often suf- ficiently brilliant to illuminate the vessel as it passes through, being produced by various species of Salpa, Bero'e, and other Molluscs, while in the former case the scintillations, which adhere in myriads to the towing net when drawn out of the water, probably originate in animalcules so minute that the only indication of their presence is the light which they emit. The author remarks that " the luminosity of the ocean is often seen with greater constancy and brilliancy of effect between the la- titudes 3° and 4° north and 3° or 4° south of the equator, than at any other part of the tropical regions. This circumstance, which I have observed myself, if found to be borne out by repeated obser- vations, may be occasioned by the eddies arising from currents, for it is a curious fact worth noticing, that where currents are known to exist, the luminosity of the ocean has been observed to assume a higher degree of brilliancy. Now the westerly current is supposed to run between those parallels of latitudes from 20° or 22° west lon- gitudes towards the Brazilian coast perpetually, and it is not im- probable that nearly at the termination of the north-east trade wind a current joins with a similar current carried by the south-east trade wind ; both uniting in forming the westerly current may thus cause a greater assemblage of the various tropical molluscs and crustaceous animals, a number of which possessing luminous properties may im- part by their presence a higher degree of phosphorescence in that particular portion of the ocean than is observed in other situations except from similar causes. That the diffusion of the phosphoric light possessed by these molluscs does not solely depend on the creatures being disturbed (such as the passage of the ship through the water, or other somewhat similar causes,) is evident, as a lumi- nous mass may frequently be observed to gradually diffuse its bril- liant light, at some distance from the ship, without any apparent disturbance ; and often during calm nights a similar glow of light is diffused over the water, without there being any collision of the waves to bring it forth ; and if a light breeze springs up during the same night, the passage of the vessel leaves no brilliant trace in its wake, although the same spontaneous diffusion of light is observed in the water at some distance to be repeated as before ; the phosphoric light being confined apparently solely to the occasional groups of molluscs, which when we succeeded in capturing them in the towing net, resembled for the most part pieces of crystal cut into various fantastic forms, round, oval, hexagonal, heptagonal, &c. From the bodies of these a faint or a bright light (according to the greater or less duration of time the animal may have been removed from the water, that is, we may say, by the intensity of its light we can judge of its healthy or vigorous state,) would be seen to issue in mi- nute doti.; Ircin various parts; and on the examination of both large Mr. Martin on the Felis Darwinii. 213 and small specimens, the large with the naked eye and the small under a powerful lens, I could not detect any one peculiar secreting organ for this luminous excretion. " It has often occurred during the voyage that the ocean became suddenly brilliantly luminous, and at other times merely a constant succession of scintillations were visible. Again, it was remarked that no luminosity of the ocean was visible except what proceeded from the wake of the ship, the other parts of the ocean exhibiting no phosphorescence. " On the 15th of April, 1835, in lat. 8° 45' north, and longitude 21° 02' west, during the day large quantities of a beautiful pink Medusa were taken in the towing net, which species I was pre- viously aware possessed luminous powers, and as expected, at night the ocean was brilliantly luminous, which luminosity continued until about 8 P.M., after which time it had almost totally disappeared. During the time the phosphorescence was visible, the Medusa before mentioned was captured in large numbers, but on the disappearance of the luminosity no more were caught, evidently showing that the phosphorescence of the sea this evening was occasioned by their l)resence. I have frequently remarked that when the ocean appears brilliantly luminous, besides the animals producing the phosphores- cence, several crustaceous animals and a number of small fish are usually taken in large quantities : the presence of these may proceed from their being attracted by the phosphoric light. Sometimes during heavy rains within the tropics the sea would become suddenly luminous, as rapidly passing off again, and the effect of the sudden transitions was exceedingly splendid to the beholders. During its continuance luminous species of Salpa, Bero'ty Pyrosoma, and other molluscs were captured in the towing net if the weather admitted of its being placed overboard." On placing some of these luminous Medusa in a bucket of water, Mr. Bennett observed that the phosphoric light is not emitted from any one particular part of the animal, but commences at different points, gradually extending over the whole body, sometimes suddenly disappearing, and at others slowly dying away. Upon squeezing the animal the hands became covered with a profusion of the luminous secretion, which could be communicated from one object to another. In conclusion several additional instances are related, occurring in different latitudes, of the beautiful and varied appearances presented by the phaenomena of marine phosphorescence*. Mr. Martin directed the attention of the Meeting to three speci- mens of the genus Felis, recently presented to the Society by Charles Darwin, Esq. One of these appeared to be a cat of the domestic race, shot in a wild state at Maldonado, differing only from our common cat in the elongation and greater size of the head. Tlie second was the ** Chat Pampa " of Azara, Felis Pajeros of Desmarest, shot at • On the subject of this paper see Prof. Macartney's Memoir in Phil. Mag., First Series, vol. xxxvii. p. 24; Mr.D. Sharpe's notice in Phil. Mag. and Annals, N.S., vol. ix. p. 144; also Mr. Brayley's paper in Lond. and Edinb. Phil. Mag., vol. vi. p. 241. 214? Zoological Society, Bahia Blanca in latitude 33. The third and most interesting speci- men, which had been shot at Buenos Ayres, Mr. Martin was dis- posed to consider as the Yagourondi or a closely allied species, since it agrees with that animal in its elongate form, stout limbs and small head, but differs from it in the greater proportionate length of tail, and also in its entire dimensions, as recorded by Desmarest, who gives the following : ft in* lin. Length from nose to the root of the tail . Ill 0 Length of tail 1 1 9 Length from nose to the ear 0 3 2 In the present specimen, which is evidently adult, the measure- ments were found to be as follows : ft. in. lin. Length from nose to root of tail » . 2 2 0 of tail 1 8 0 — — — from nose to ear 0 3 9 Height at shoulders. 0 11 6 at haunches 1 0 6 Length of ear 0 1 2 Breadth of ear 0 I 6 From nose to eye 0 1 2 The hair is black, annulated with ochre, and sometimes with whi- tish yellow; each hair is pale brown at the base and then alternately black and yellow, the colours being repeated two or three times. Upon the head the yellow colour is most prevalent. The under fur is thick and of a pale brown colour. The hair is about the same length or rather shorter than in the domestic cat, and much harsher to the touch. The hind feet are black beneath from the heel to the toes, and there is a streak of black about an inch and a half in length, passing upwards from the front paw on the outer side. The hair of the tail is long and bushy ; the legs thick and moderately long; the general form is slender ; the head small in proportion to the body, and considerably arched above. The region of the ante- rior angle of the eye is black, with a yellowish white spot immedi- ately above it. The eyes are very small; the ears short, broad, and obtusely pointed, thickly covered with hair, which on the outside is of a similar colour to that on the top of the head, excepting at the tip, where it is margined with black. Inside the ears the hair is of a paler hue. The under parts of the body are of the same general hue as the sides. The tail is of the same general colour as the body, but the hairs become gradually less annulated towards the tip, their basal portions being brown and the apices black ; the under side is of a somewhat paler hue than the upper. The lips and nose are black. Mr. Martin remarked, that there was some reason for supposing two species were confounded under the same name, for he was aware of the existence of a cat with a shorter tail, agreeing very closely with Azara's description of the Yagourondi. Without, however, being in possession of more ample materi£ds he did not like to characterize Zoological Society. 215 the present siDCcimen as a new species, but in the event of its ulti- mately being considered distinct, he proposed that it should be called Felis Darwinii. Mr. James Reid read some notes on several quadrupeds, also from the collection of Mr. Darwin, including a new species of Opossum, which he characterized as Didelphis hortensis. He also noticed a very young specimen of the Viscache, Lagostomus trichodactylus of Brooks. This example, not much larger than our common Rat, dif- fers from the adult in wanting the ridge of stiff black hairs over the eyes so conspicuous in old specimens, and in wanting also the grooves on the teeth. Mr. Gould exhibited from Mr. Darwin's collection of Birds, a series of Ground Finches, so peculiar in form that he was induced to regard them as constituting an entirely new group, containing 14 species, and appearing to be strictly confined to the Galapagos Islands. Mr. Gould believed the whole of these Birds to be un- described, and remarked that their principal peculiarity consisted in the bill presenting several distinct modifications of form, while the general contour of the species closely assimilated. He proposed to characterize them under the separate generic appellations of Geo- spiza, Camarhynchus, Cactornis, and Certhidea. Their characters will be found in No. xlix. of the Proceedings. Mr. Gould then resumed the exhibition of a portion of his own collection of Birds from Australia, and characterized as a new spe- cies Hemipodius melanogaster, the characters of which are given in the Proceedings. Mr. Gould also exhibited a new and interesting species of Parrot, presented to the Society by Mr. John Leadbeater, and which he cha- racterized on behalf of the donor, a.s Platycercus Ignitus, its characters being given in the Proceedings. January 24, 1837. — Mr. Gould exhibited the 'Raptorial Birds in- cluded in the collection recently presented to the Society by Charles Darwin, Esq., and after some general observations upon the geogra- phical distribution of the known species, proceeded to characterize the following as new to science : PoLYBORUs galapagoensis. Were I not assured by Mr. Darwin that the habits of this bird strictly coincide with those of the Caracara {Polyhorus Brasiliensis), its mode of flight and cry being precisely the same, I should have been induced to regard it as rather belonging to the genus Buteo than to Polyhorus ; but as I have satisfactorily ascertained by a close investigation, it forms a beautiful intervening link between these genera, as is evidenced by the scaling of the tarsi and the produced form of the beak; while its habits place it within the limits of the latter genus. It is on the authority of Mr. Darwin also that I rely for the as- surance of the two birds above described being the male and the female of the same species, so great is the difference between them both in size and colour. 2 1 6 Intclltfjrence and Miscellaneous Articles* 'to PoLYB. (Phalcobsenus) albogularis, I have some doubts as to whether this bird may not eventually prove to be a variety of Phalcohcenus montana, D'Orb. The prin- cipal difference between this bird and the one described and figured by M. D'Orbigny is, that the throat and chest of the latter are brownish black, while the same parts in this bird are white. BuTEO var%us2iXsABut. ventralis; Circus megaspilus and OTUs(Bra- chyotus) galapagoensis. On the last-named bird Mr. Gould observes : lliis species belongs to that section of the homed owls which comprehends the short- eared owl of England, and numerous other nearly allied species which are distributed universally over the globe, from all of which it may be distinguished by its smaller size and darker colouring. I am led to regard the members of this sec- tion as possessing characters of sufficient value to justify their being separated into a distinct genus, for which I propose the name of BracUyotus, XXXI. Intelligence and Miscellaneous Articles, PREPARATION OF PROTOXIDE OF TIN. OWING to the great difficulty of preparing protoxide of tin accord- ing to the directions generally given in chemical works, I was led to make some experiments on the subject. I find the following process to be that which yields the purest oxide. Prepare a solution of pro- tochloride of tin by dissolving the metal in hydrochloric acid, taking care always to have a great excess of the metal ; the solution is then evaporated to dryness, together with a lump of tin to prevent the formation of perchloride. The tin is then separated, and the chlo- ride weighed, and rubbed in a mortar with its equivalent, or rather more, of crystallized carbonate of soda ; the mixture soon becomes fluid ; it is then put into an evaporating dish and heated on the sand- bath, frequently stirring, till it becomes thoroughly black ; it is then removed and well washed with boiling water, filtered, and dried at a gentle heat on the sand-bath. The oxide thus prepared is of a beau- tiful blue-black or slate colour ; it is very soluble in hydrochloric acid, and when heated to dull redness in the air, it takes fire and burns, and is converted into peroxide. St. Thomas's Hospital, January '3rd, 1838. S. A. Sandall. PREPARATION OF BICARBONATE OF POTASH, BY PROF. WCEHLER. Carbonate of potash, both in the dry state and in solution, com- bines very slowly with the second equivalent of carbonic acid to form the bicarbonate of potash. By means of charcoal in a finely divided state the combination may be made to take place very easily. It can be performed in the following manner : bitartrate of potash is to be heated in a covered crucible, the burnt mass to be moistened with water, put into a receiver, and carbonic acid passed through it. The absorption takes place with such rapidity that the mass becomes Nedo Arsenical Copper, 217 strongly heated, so much so that it is necessary to surround the re- ceiver with cold water to prevent the reconversion of it into carbon- ate of potash. Tlie saturation is complete when it ceases to give out heat. It is then dissolved in the smallest possible quantity of water at the temperature of 100° to 120° Fahr.; upon the cooling of the filtered solution, the greater part of the bicarbonate separates in fine crystals. — Poggendorffs Annals. NEW LOCALITY OF ARSENICAL COPPER IN CHILI, BY VON ZINKEN. Amongst some Chilian minerals from San Antonib, near Copiapo, was some massive native silver, accompanied by a tin-white substance, which, when broken, has somewhat the appearance of copper py- rites ; this locality also furnishes native copper, native silver con- taining copper, polybarite, and calcareous spar. The fracture of this new mineral is uneven ; it occurs tabular, kidney-shaped, and mas- sive ; it scratches calcareous spar, but is scratched by fluor spar and a knife ; its specific gravity is not easily determined, as it is always accompanied by native silver. Exposed to heat in an open tube, it gives out arsenious acid, then a white vapour, (oxide of antimony ?) ; upon increasing the heat it is converted into a red scoriaceous mass, which attacks the glass, and imparts to it the colour of oxide of cop- per ; the fumes also smell of sulphureous acid. The roasted mineral fused with soda gives a button of copper not containing silver. Melted with borax, it gives a red and yellow scoriaceous mass, and a bead of copper. It is acted upon violently by nitric acid, which dissolves it, leaving a black flocculent residue recognisable as sulphur, mixed with a little arsenic. This mineral is therefore a compound of arsenic, sulphur, antimony, and copper, and is somewhat similar to condurrite, an arsenical copper found at Condurrow, near Camborne, Cornwall. — Poggendorff's Annals, vol. 41, p. 392. DEFINITE COMBINATION OF OXIDE OF SILVER AND OXIDE OF LEAD, BY PROF. WCEHLER. When a salt of silver is contained in a solution of a salt of lead, caustic alkali throws down a yellow precipitate, — a reaction which is of great interest in analytical chemistry. This yellow precipitate is insoluble in excess of caustic alkali ; but by digestion in the latter, any free oxide of lead precipitated with it may be separated. This yellow substance, according to analysis, is a combination of 1 equiva- lent of oxide of silver, and 2 equivalents of oxide of lead ; and 100 parts consist of 34*23 oxide of silver, and 65*77 oxide of lead. Upon exposure to the light it turns black. Upon heating to redness it gives a mixture of metallic silver and oxide of lead. In hydrogen gas it is reduced to an alloy with a very gentle heat. It is easily soluble in nitric acid. In a mixture of a salt of silver with a salt of protoxide of manga- nese, a caustic alkali throws down a black precipitate. This appears to be a very intimate mixture of metallic silver with peroxide of manga- nese. It is dissolved by acids without ihe disengagement of any gas 218 Intelligence and Miscellaneous Articles, and therefore without the decomposition of the acids, because the silver is oxidated by the oxygen of the peroxide of manganese. — Poygendorff's Annals, v. 41, p. 344. A NEW METHOD OF OBTAINING CHROME ALUM, BY R. F. MARCHAND. When bichromate of potash is dissolved in hot hydrochloric acid, upon cooling, the crystallized compound, discovered by Peligot, of chromic acid with chloride of potassium is formed, and there remains in the mother liquor chloride of potassium and chloride of chrome. If, instead of the bichromate, the chromate of potash is substituted, no compound of chromic acid with chloride of potassium is formed, but a mixture of chloride of chrome and chloride of potassium is ob- tained ; the latter salt may be completely separated by crystallization. If to the hydrochloric acid about one-eighth of its weight of sul- phuric acid is added, one half of the chromic acid is converted into oxide of chrome, which combines with the sulphuric acid and the sulphate of potash, and the double salt of chrome alum is obtained ; at the same time there is formed chloride of potassium, which, if sulphuric acid is added in excess, is converted into sulphate of pot- ash, and bichloride of chrome is formed, which, upon evaporation, disengages chlorine with the production of chloride of chrome. Fischer's method of preparing chrome alum by means of bichro- mate of potash, alcohol, and sulphuric acid, is so simple and advan- tageous, that any other method of procuring it is rendered unneces- sary ; but still the formation of oxide of chrome from chromic acid, by this method, is not altogether without theoretical interest, even if, in practice, it cannot be turned to account. — Poggendorff's An^ nals, p. 594. EXAMINATION OF MALT LIQUORS. Professor J.N. Fiichs of Munich has devised the following method of examining malt liquor with regard to the ingredients contained in it, which he calls a " Hallymetrische Bierprobe." It is founded on the solubility of common salt in water; 36 parts of salt che- mically pure being dissolved by exactly 100 parts of water. A graduated tube is previously prepared, called a ** Hallymeter." It consists of two glass tubes, one narrow, the other wide, joined to- gether, somewhat funnel-shaped, of a capacity rather more than suf- ficient to hold the required fluid and the undissolved salt. The smaller and lower part of the tube is so graduated as for the larger divisions to contain 5 grains of prepared salt with space between each division, so that it may be divided into tenths : it is graduated with powdered salt in a saturated solution of salt, the salt being pre- viously sifted through a fine sieve. First process. — 330 grains of common salt are added to 1000 grains of the beer under examination in a covered glass vessel. It is heated in warm water to the temperature of 100° Fahrenheit ; the salt is thereby dissolved in about five minutes. It is cooled, and by care- fully blowing through it, all the carbonic acid is expelled. The so- Prof. Fiichs 07i the Examination of Malt Liquors, 219 lution is weighed, and the loss of weight is the carbonic acid, which suppose to be 1^ grain, which is about the quantity contained in good beer. The contents of the glass vessel are poured into the '* Hallymeter," taking care that no portion of the undissolved salt is left behind ; the undissolved salt must be brought into the smallest possible space by being shaken down until it will not sink any lower in the tube, which will require 15 minutes. By referring to the graduated scale on the tube, it will show how much salt remains undissolved ; this quantity, deducted from the quantity first taken, will give the quantity dis- solved. Thus 330 grains of salt added to 1000 grains of beer, gave, by trial, 17*3 grains of salt undissolved; therefore 17*3 from 330 give 312*7 grains dissolved, which is equal to 868'61 grains of water, (36 grains of salt being dissolved by 100 of water) ; this 868*61 grains, deducted from the 1000 grains of beer under examination, leaves 131*39 grains as the whole of the ingredients contained in the beer. Second process {for ascertaining the weight of the extract only). — Another portion of 1000 grains of beer is taken and evaporated down to one half, by which means all the spirit of wine is driven off; it is cooled and weighed, and treated with a proportionate quan- tity of salt as before. In ordinary cases it is advisable to add 180 grains of salt to the evaporated solution ; thus, if to the 500 grains 180 grains of salt have been added, and there remain 21*3 grains of salt undissolved, then 158*7 grains have been dissolved, which is equal to 440*83 grains of water; this, deducted from 500 grains, gives 59' 17 for the extract ; now add to the extract 1*5 for carbonic acid (as by first process), and deduct this amount 60*67 from the quantity found by the first process, 131*39; there remains 70*72 grains for the spirit of wine. The 1000 grains of beer therefore consist of 868*61 water, 70*72 spirit of wine, 59*17 carbonic acid, 1*50 extract. 1000* As it is necessary that the common salt should be chemically pure, Mr. Fiichs has given the following process for obtaining it from ordinary salt. Purification of Common Salt. The salt is dissolved in lime-water, or if it contains much mag- nesia, in very weak cream of lime. To the clear solution muriate of barytes is added as long as any precipitate falls ; it is then filtered, and carbonate of ammonia, with a little caustic ammonia, is added, by which the lime and excess of barytes are precipitated. After stand- ing 24 hours, it is tested by oxalate of ammonia ; and if no cloud- iness ensues after two hours, it is free from lime. The clear solu- tion is then evaporated, and the residue submitted to a low red heat ; a saturated solution, exposed to a temperature of about 50° Fahren- heit, [query 30°,] deposits crystals of pure salt. 220 Litelligencc and Miscellaneous Articles, ON SOME NEW COMPOUNDS OF CHLORINE. BY MONS. H. ROSE, Hitherto the composition of the volatile compounds of chlorine has been determined by means of the known composition of the ox- ide or oxacid, formed by the decomposition of water, at the same time as hydrochloric acid. Since, however, the discovery of chro- mate of chloride of chromium, (2 Cr + Cr Cl^)*itis no longer pos- sible to apply the same mode of determination to the composition of all the volatile compounds of chlorine, and it became necessary to submit to a quantitative analysis such of these combinations, in the formation of which a substance containing oxygen was employed. M. Rose, proceeding on this principle, has discovered that the two bodies which are formed by the reaction of chlorine gas upon the oxides of tungsten and molybdena, the chloride of tungsten and the chloride of molybdena, possess a composition analogous to the chro- mate of chloride of chromium. As they are converted into hydro- chloric acid, and tungstic or molybdic acid, when treated with water, it was supposed that their composition was analogous to that of the two last acids. In fact, during the preparation of chloride of tung- sten there is obtained, besides the chloride, another more volatSe chloride corresponding to the oxide of the same metal, and also a tungstic acid which is not volatile. The same products, formed by the decomposition of the chloride, appear when it is suddenly exposed to a strong heat. Thus, it is not entirely composed of tungsten and chlorine, but must contain oxygen ; the volatile compound cannot, however, be obtained perfectly free from excess of tungstic acid, which mixes with it during its formation. The same happens with hyperchloride of molybdena as with chloride of tungsten ; their com- position may therefore be represented by 2 W + W Cl^ and by Mo C13. The chromate of chloride of chromium, above described, is the result of the reaction of chromate of potash, chloride of sodium, and sulphuric acid. If, instead of employing chloride of sodium, bromide of sodium or potassium be substituted for it, bromine is obtained quite free from chromium. This difference of reaction admits of the detection of slight traces of a metallic chloride in large quantities of metallic bromides, which would otherwise be extremely difficult. If bromide of potassium or sodium be submitted to distillation with chromate of potash and sulphuric acid, and if the product of the dis- tillation be received in ammonia, no trace of chromium will be found in it, if the salt was quite free from chloride of potassium or sodium. — Journal de Chimie Medicale, December 1837. NEW ACID FORMED BY THE COMBUSTION OF ALCOHOL AROUND AN INCANDESCENT TLATINA WIRE. M. Leroy states that this acid is liquid, and of a consistence similar to that of the oil of sweet almonds or olives, and that it is perfectly limpid. It is greasy and unctuous to the touch ; it spots paper like. • See Mr. Walter's paper, p. 83 of our last number. M. Trommsdorff 072 Gentianin, 221 a fat substance, and the spot remains for shorter or longer time, ac- cording to the temperature. It has a slight smell when totally freed from acetic acid. This odour is peculiar, and not at all aromatic ; it has a bitter taste ; its after taste is sharp, and resembles that termed metallic. Its specific gravity at 47° Fahr. is 1*13 15; it is slightly volatile, and reddens litmus paper strongly. The chemical properties of this acid are, that it boils between 122^ and 13P Fahr,, and gives off pungent vapours which affect the eyes. It is, however, less volatile than water and concentrated acetic acid ; it becomes more viscid at a few degrees below 32°, and is nearly as thick as soft butter. Light does not appear to act upon it ; the ac- tion of the air is but little known. This acid, when kept in half- filled bottles, appears to be converted into very concentrated acetic acid, and a volatile product. Do these result from the absorption of oxygen ? It combines with water in all proportions : *the solution reddens litmus paper strongly. When mixed with liquid ammonia, it does not at first appear to suffer any alteration ; but if the mixture be heated to 80'' Fahr., it soon becomes of a brown colour ; if the temperature be raised to IGO**, the colour becomes deeper and deeper; if it be then suddenly cooled, a glutinous product is obtained, which is of a dark colour, and in which numerous crystals may be perceived. This production of this colour, says the author, I had attributed to the action of the heat ; but having taken fresh portions of ammonia and the acid in the same proportions, and left them exposed to the atmosphere in a watch- glass, it became coloured in twenty-four hours, but no crystals were formed. This mixture is volatile. Does this acid contain aldehyde } Are the crystals the ammonaldehyde of Liebig ? In the absence of proof, opinion should be suspended. I thought, at first, the brown- coloured product the aldehydarz of Liebig: I then threw it into water, and it dissolved totally without the slightest residue. When this acid is put into contact with fine crystals of nitrate of mercury, the mixture becomes milk-white ; but if heated to a tem- perature between 140° and 160°, ebullition occurs, vapours are given off which affect the eyes very powerfully, and a globule of a greyish- blue colour soon forms at the bottom. This globule, says M. Leroy, seems to be cemented by a fatty matter, and on examining it with a strong glass, small brilliant points were perceptible, which appeared to be globules of mercury. When a lighted taper is presented to this acid, it burns with a white flame. — Journal de Chimie Medicale, December 1837. ON GENTIANIN. BY M. TROMMSDORFF. MM. Henry and Caventou, in 1821, first separated a crystalli- zable substance from gentian root. They attributed all the bitterness of the plant to it, and CEdled it gentianin. This substance was a mixture. According to TrommsdorfF, it may be obtained pure by the following process. Treat two pounds of gentian root with aether till it ceases to dissolve anything ; the greater part of the aether is to be separated by distillation, and the remainder is to be treated 222 Intelligence and Miscellaneous Articles, with alcohol. The evaporation of the filtered liquor gives a deep yellow-coloured residue of a crystalline appearance, and containing much resin ; to deprive it of which it is to he repeatedly washed with small portions of cold aether. In this operation, the aether acquires a yellowish-brown colour, and is most intensely bitter : by evaporation it leaves an uncrystallizable residue. The gentianin thus obtained has a decidedly bitter taste, derived from a small quantity of resin. It is to be dissolved in a small quan- tity of alcohol, to be crystallized, and again washed with cold aether. The crystals, after each washing, are to be pressed between filtering paper. Two pounds of gentian yielded only about 120 grains of gentianin. Gentianin is in the state of fine silky needle-form crystals, and of a sulphur-yellow colour ; it is but very slightly bitter, and this bit- terness is entirely got rid of by repeated solutions in, and crystal- lizations from alcohol, after which it is insipid, even when in solution. Gentianin is insoluble in cold water, very slightly dissolved by boiling water, and much more soluble in alcohol and aether. When heated to a temperature of above 212°, it sublimes entirely, and con- denses into silky yellow crystals. The subacetate of lead and nitrate of silver do not precipitate it from solution. The chloride of iron and the salts of copper give a precipitate. It strongly resists the action of acids. Some very con- centrated mineral acids only appear to decompose it. Some seem also to render it more soluble in water. It does not act upon litmus paper. The most remarkable circumstance is, not only that it dissolves with the utmost facility in alkaline solutions, and becomes of a bright golden colour, but it combines with the alkalies in several definite proportions. These compounds are yellow, crystallizable, and pos- sess an alkaline reaction. This acid (for it is one) decomposes the alkaline carbonates, expelling the carbonic acid.-— Jbwr^a/ de Chimie Medicate, December 1837. ON QUASSIN. Wiggers gives the name of quassin to the bitter principle of the Quassia amara and Quassia excelsa. The following is the process which he employed to obtain it ; boil the wood, cut into thin slices, in water; filter and evaporate the solution to three quarts ; afterwards allow it to cool, and add some lime water to it, and leave them together for a day. The lime separates the pectin and the other substances. Filter and evaporate to drj^ness, and add to the residue about 80 or 90 per cent, of alcohol. This menstruum dissolves the quassin, a little chloride of sodium, nitrate of potash, and an organized brown- ish matter. By distillation a residue of a light yellow is obtained ; this is to be treated with a mixture of absolute alcohol and aether, until the quassin appears pure. A little water is to be added to this solution, and it is to be allowed to evaporate in the air. A fresh quantity of quassin may be obtained by collecting the substances separated by the rether, and by treating them afresh with absolute Meteorological Observations. 22 3 alcohol and sether, as already described. The quassin has the form of small white prisms ; it is very slightly soluble in water, 100 parts dissolving only 0*45. The aqueous solution of quassin is precipitated white by tannin ; chlorine and iodine produce no effect upon it. It is scarcely soluble in a;ther ; alcohol is the best solvent, the action of which is greater the more highly rectified it is, and as the tem- perature is higher. All its solutions are colourless. ITie quassin is a neutral body ; the sulphuric and nitric acids dissolve it, but do not combine with it, nor are they neutralized by it ; heat separates them and leaves the quassin pure. It is composed of Hydrogen 6-827 Carbon 66'912 ^ Oxygen 26-261 100- '^Journal de Chimie Medicate, December 1837. NEEDLES RENDERED MAGNETIC BY THE NERVES. The Compte Rendu for January 2, 1838, which we have just re- ceived, contains the following important notice : M. Becquerel made the following communication to the French Academy from a letter he had received from M. De La Rive : " Dr. Prevost, of Geneva has succeeded in magnetizing very delicate soft-iron needles, by placing them near to the nerves, and perpendicular to the direction which he supposed the electric current took. The magnetizing took place at the moment when on irritating the spinal marrow a muscular contraction was effected in the animal." — [W. F.] METEOROLOGICAL OBSERVATIONS FOR DECEMBER 1837. Chiswick. — Dec. 1. Clear: very fine: frosty at night. 2 — 5. Dense fog. 6. Cloudy and cold : snow at night. 7. Sleet : hazy. 8. Foggy : showery. 9. Foggy. 10. Hazy: very fine. 11 — 13. J'ine. 14. Frosty: very fine. 15, 16. Fine. 17. Rain. 18. Stormy and wet. 19. Over- cast : rain. 20. Boisterous with rain. 21. Cloudy: very fine. 22. Drizzly. 23. Slight haze. 24. Hazy. 25. Very fine. 26. 27. Hazy and mild. 28—31. Very fine. Boston. — Dec. 1. Fine : rain early a.m. 2. Fine. 3, 4. Foggy. 5. Cloudy. 6. Cloudy : snow p.m. 7. Cloudy : rain p.n. 8. Cloudy : rain early A.M. 9. Cloudy. 10, 11. Cloudy: rain early a.m. 12. Fine: rain p.m. 18, 14. Cloudy. 15, 16. Fine : rain p.m. 17. Cloudy. 18. Cloudy : rain early a.m. 19. Cloudy : rain p.m. 20. Rain : hur- ricane with rain p.m. 21. Cloudy. 22—24. Cloudy : rain early a.m. 25. Fine : rain early a.m. 26— 29 Cloudy. 30. Fine. 31. Fine: rain early a.m. e> ! I 60 « ft? I ^ CO •: J 3 ^ o o o • o • rO-^ VD lO to . <0 0> "O 00 >-0 . 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a' db da da db da db d.lE d, a) _ d(p dt d(p dt ds d^' dt ~~ db da da db da db ds d Address of the President, 2'73 tions in oriental literature and oriental science. In the course of a few years there appeared from his pen many profound dissertations in the Asiatic Researches, on the Vedanta System of Philosophy, on Sanscrit and Pracrit Poetry and Grammar, on the Indian Classes, on the Origin and Tenets of the Mahometan Sects, on the Jains, on the Indian and Arabian Division of the Signs of the Zodiac, and on the Notions of the Hindu Astronomers on the Precession of the Equinoxes and the Motions of the Planets ; to which must be added the first volume of a very elaborate Sanscrit Grammar, the translation of the Peostra, a Sanscrit Dictionary, and two extensive Treatises on the Hindu Law of Inheritance, together with editions of the AmeraCosha, a Sanscrit Vocabulary, and of the Hitopadesa, or " Salutary Instruction", which had been translated by Mr. Wil- kins, and which is more commonly known under the name of the « Fables of Pilpay". It was some time after Mr. Colebrooke's return to this country that he published, in 1817, a translation of the Lilawati and Vija- Ganita, Sanscrit treatises on arithmetic, algebra and mensuration, to which was prefixed a dissertation on the early history of algebra and arithmetic in India, Arabia and Italy, which is equally remarkable for its profound knowledge of Hindu and Arabian literature and its correct views of the relations of oriental and ancient and mo- dern European science. He was also the first person who main- tained, from his own observations on the plains of Hindostan, the superior elevation of the Himalayan mountains above the Andes of America, in opposition to the opinions generally entertained at that period, and which had been sanctioned by the great authority of Humboldt's theory of the range of the curve of perpetual congela- tion. The complete confirmation which his opinion afterwards received, from accurate barometrical and trigonometrical measure- ments, was always referred to, in his later years, with particular sa- tisfaction and triumph. Mr. Colebrooke continued the steady pursuit of his oriental and scientific studies until nearly the close of his life, ^nd even when the progress of his infirmities confined him almost entirely to his bed. He was one of the founders of the Asiatic and Astronomical Societies, and a short time before his death he gave to the library of the India House his incomparable collection of Sanscrit and Asiatic manu- scripts, which had been collected at an expense of nearly 10,000/., with the noble view of preserving them for ever from the danger of dispersion by the fluctuating accidents of inheritance. Mr. Colebrooke was probably, with one single exception, the greatest Sanscrit scholar of his age ; and when we take into account his great acquirements in mathematics and philosophy, and in almost every branch of literature, combined with the most accurate and severe judgement, and also his great public services in situations of the highest trust and responsibility, we shall not hesitate to pro- nounce him one of the most illustrious of that extraordinary suc- cession of great men who have adorned the annals of our Indian Phil. Mag, S. 3. Vol. 12. No. 74. March 1838. 2 E 274? Royal Society, empire, the deaths of so many of whom it has been my misfortune to record in my recent addresses from this chair. Dr. John Latham reached the extraordinary age of ninety-seven years, having enjoyed the full possession of his faculties and almost unbroken health until within a few days of his death : he was the father of the Royal and Antiquarian Societies, and it is sixty-seven years since his first paper, on a medical subject, was published in our Transactions. He was the author of many papers on antiquarian subjects; but his favourite study throughout life was natural history, and particularly ornithology. He published, in 1781, his General Synopsis of Birds, in six volumes quarto, and afterwards two supplementary volumes. In 1792 he published his Index Ornithologicus, a complete system of ornithology, arranged in classes, orders, genera and species, in two volumes quarto. At the age of 82, he commenced his General History of Birds, a magnificent work in eleven volumes quarto. He was a man of very systematic habits and most amiable character, the tran- quil course of whose long life was neither disturbed by scientific orpro- ' fessional jealousies, nor embittered by the want of those enjoyments which competence and domestic happiness and virtue alone can confer. Dr. Tiarks was born at Jever in Oldenburg, and came to England in 1810, when he was appointed Assistant-Librarian to Sir Joseph Banks, through whose influence he was nominated Astronomer to the Commission for settling the North American Boundary, under the authority of the Treaty of Ghent. After his return to England, in 1822, he was commissioned by the Admiralty, at the request of the Board of Longitude, to ascertain, by means of a great number of chronometers, the difierence of the longitudes of Falmouth and Madeira, and subsequently of Falmouth and Dover, the results of which were detailed in a very able paper in our Transactions for 1824, in which he pointed out and explained the origin of an error of nearly 4" of time in the longitudes of all the stations of the Tri- gonometrical Survey*. He was afterwards sent on a similar mission to Heligoland and various stations in the North Seas, and on the last occasion he was accompanied by Sir Humphry Davy, who wished to try the effect of his protectors on the corrosion of the copper sheathing of ships. In 1 825 he was recalled from Germany to resume his astronomical surveys in America, where he was em- ployed to ascertain the position and extent of the north-western boundary'' of the Lake of the Woods, an operation in the execution of which both he and the party who assisted him suffered the great- est hardships and privations. He published various reports of his surveys, and was necessarily much employed and consulted in the difficult and embarrassing negotiations which have attended, and unhappily still attend, the settlement of the important question of the North American boundaries. Dr. Tiarks died in the forty- eighth year of his age, at his native place, in consequence of a fever which attacked a constitution already shattered and broken by the severe labours and privations which he had endured. He was a * See Phil. Mag., First Series, vol. ixiii. p. m^ 378, Aniizversar?/ of IS3^, Address of the President 275 mathematician of no inconsiderable attainments, a very careful and efficient practical astronomer, and admirably qualified for the very important and responsible duties which he was appointed to dis- charge. Dr. Edward Turner was a native of Jamaica, and studied medi- cine at Edinburgh, and chemistry at Gottingen under the instruc- tions of the celebrated analytic chemist Stromeyer. He became a lecturer on chemistry at Edinburgh in 1824, and his first publica- tion was a short introduction to the study of the laws of chemical combination and the atomic theory. He obtained the Professorship of Chemistry in the London University at its first establishment in 1 828, a situation which he continued to hold to the end of his life. His Elements of Chemistry have enjoyed an uncommon degree of popularity, and are remarkable for clearness and precision both in the description of his experiments and in the deduction of his theory*. He was the author of two papers in our Transactions ; the first "On the Composition of the Chloride of Barium," and the second containing " Researches on Atomic Weights," both written with a view of impugning the theory which had been promulgated by some English chemists of high authority, " that all atomic weights are simple multiples of that][of hydrogenf ." In the year 1835 Dr. Turner was compelled by the declining state of his health to suspend all original researches, confining himself simply to the duties of his professorship ; and he died in February last, in the fortieth year of his age, to the deep regret of every friend of the progress of chemi- cal science. He was a person of most engaging manners and ap- pearance and of most amiable character; and his body was fol- lowed to the grave, with every manifestation of respect and affection- ate attachment, by the whole body of the pupils and professors of the institution of which he had so long been a principal orna- ment. Dr. William Ritchie was originally Rector of the Royal Academy of Tain in Inverness-shire, where he contrived, by extreme frugality, to save a sufficient sum from his very small annual stipend to attend a course of the lectures of Thenard, Gay-Lussac, and Biot at Paris, and also to provide a substitute for the performance of his duties during his temporary absence from Scotland. His skill and ori- ginality in devising and performing experiments with the most simple materials, in illustration of various disputed points of natural phi- losophy, attracted the attention of the distinguished philosophers whose occasional pupil he had become : he had also communicated, through Sir John Herschel, who took a strong interest in his for- tunes, to the Royal Society, papers " On a new Photometer," " On a new form of the Differential Thermometer," and " On the Permea- bility of transparent Screens of extreme tenuity by Radiant Heat," * This work was reviewed in Phil. Mag. and Annals, N.S., vol. L p. 379. t Dr. Turner's paper on the chloride of barium was given in Phil. Mag. and Annals, N.S., vol. vHi. p. 180 ; and abstracts of his Researches on atomic weights in L, & E. Phil. Mag., vol. i, p. 109; iii, p. 448. 2E2 276 Royal Society. whiqh led to his appointment, through the recommendation of Major Sabine, to the Professorship of Natural Philosophy at the Royal In- stitution, where he delivered a course of probationary lectures in the spring of 1829 : he became, from this time, a permanent resident in London, and was appointed to the Professorship of Natural Philo- sophy at the London University in 1832. He subsequently commu- nicated to the Royal Society, papers " On the Elasticity of Threads of Glass, and the application of this property to Torsion Balances ;" and also various experimental researches on the electric and che- mical theories of galvanism, on electro-magnetism and voltaic elec- tricity, which are more remarkable for the practical ingenuity mani- fested in the contrivance and execution of the experiments, than for the influence of the views which they display on the progress of their theory, which was so fully and so happily developed by the contem- porary labours of another illustrious chemist and philosopher. Dr. Ritchie was subsequently engaged in experiments, on an exten- sive scale, on the manufacture of glass for optical purposes, for the examination of the results of which a Commission was appointed by the Government, with a view to their further prosecution by a public grant of money, or by affording increased facilities of experiment by a relaxation of the regulations of the Excise. A telescope of 8 inches aperture was made by Mr. DoUond from Dr. Ritchie's glass, at the recommendation of this commission ; but it is generally understood that its performance was not so satisfactory as to sanction a further expenditure in the extension of these experiments. Dr. Ritchie died in the autumn of the present year, of a fever caught in Scotland ; and though the traces of an imperfect and irregular education are but too manifest in most of his theoretical researches, yet he must always be regarded as an experimenter of great ingenuity and merit, and as a remarkable example of the acquisition of a very extensive knowledge of philosophy under difficulties and privations which would have arrested the progress of any person of less ardour and determination of character*. Mr. Joseph Sabine was educated in the University of Dublin, and devoted himself, from a very early period of life, to the study of botany, ornithology, and other branches of natural history, to the neglect of those professional studies which his friends designed him to pursue. One of 'his earliest labours was the formation of a col- lection of British birds of almost unrivalled extent and completeness. He became secretary to the Horticultural Society at the period of its first establishment ; and though his connection with it was after- wards very abruptly and perhaps very harshly terminated, he must always be considered as the chief author of its successful and com- plete development. To the Horticultural Transactions he contri- buted 64 papers, the most important of which are those on the ge- • Abstracts of Dr. Ritchie's papers read before the Royal Society will be found in Phil. Mag. and Annals, N.S., vol. vi. p. 52 ; viii. 58 ; x. 226; xi. 448; and L. & E. Phil. Mag., vol. iii. pp. 37, 145 ; x. 220; xi. 192. Papers communicated by him to the Philosophical Magazine have appeared in nearly every volume of the present series. Anniversary of 1837 » Address of the President, 277 nera Crocus^ Dahlia^ and Chrysanthemum ; and he was also required to re-write the greatest part of the communications which were ad- dressed to the Society by gardeners and practical men, which were rarely sent in a fit state for publication, but which frequently em- bodied very important information on the various processes of hor- ticulture. Mr. Sabine was likewise an active and valuable member of the Zoological Society, whose gardens are chiefly indebted to his taste and knowledge for the introduction and systematic arrangement of those splendid flowers and shrubs which have added so greatly to their beauty and interest. Mr. Sabine held, for the greatest part of his life, the situation of Inspector-General of Taxes, and was called upon by his official du- ties to make periodical visits to almost every part of the kingdom ; he never omitted any opportunity which his various journeys afforded him, of acquiring or of communicating practical knowledge of hor- ticulture and of botany ; and few persons have contributed so much, by their personal exertions, to add to the decorations of the cottage and the park, to increase and improve the produce of our gardens, and thus greatly to extend the sphere of the innocent enjoyments and luxuries of all classes of society. The Rev. Dr. Joseph Hallett Batten was a native of Penzance in Cornwall, and was elected a Fellow of Trinity College, Cambridge, in 1801, after attaining very high academical honours. He was ap- pointed Classical Professor at the East India College at Hayleybury at the period of its first establishment, and became Principal of the college upon the retirement of Dr. Henley, a situation which he con- tinued to retain until within a month of his death. He was a man of cultivated taste and of very extensive attainments, both in theo- logy and general literature ; and in every way worthy, by his intel- lectual powers and character, of presiding over an establishment which has been so justly distinguished by the very eminent men who have been, and now are, connected with it. Dr. John Johnstone was the sixth son of the celebrated Dr. James Johnstone of Worcester, and received his education at Merton Col- lege, Oxford. He was for upwards of forty years a very distin- guished physician at Birmingham and its neighbourhood, and made his first appearance as an author in a defence of his father's claim to the first discovery of the disinfecting powers of muriatic acid gas, which had been claimed by Dr. Carmichael Smyth. Though ear- nestly attached to the study and practice of his profession, he re- tained throughout life a fondness for classical literature, and lived on the most intimate terms with some of the most distinguished scholars of the age, including amongst their number the justly cele- brated Dr. Parr, whose life and voluminous correspondence he pub- lished, a work full of interesting literary anecdote and classical re- search; and his Harveian oration, pronounced in 1819, and which has been recently published, with a short memoir of his life, by his friend the Bishop of Lichfield, is a model of spirited and correct Latinity. Dr. Johnstone was a man of very warm affections and of 278 Royal Society^ great independence of character, and he was universally respected in the great manufacturing city in which he resided, for his great pro- fessional skill and services, and for the active support which he gave to every benevolent and useful institution. Sir John Soane received his early architectural education under Mr. Dance and Mr. D. Holland, and was afterwards sent, by the especial bounty of King George the Third, as a student of the Royal Academy, to pursue his professional studies at Rome. After his return he gradually obtained extensive employment, both as an ar- chitect and a surveyor, and finally succeeded in securing almost every important and honourable appointment which is connected with the exercise of his profession in this country. In later life, when in possession of an ample fortune and public honours, he became a most munificent patron of public institutions, and more particu- larly of those which are connected with the advancement of the fine arts; and in 1835 he bequeathed his house in Lincoln's Inn Fields, and the magnificent collection of works of art which it contained, to the nation, and secured the accomplishment of this noble project by an Act of Parliament ; he continued to pursue his usual course of public munificence until his death, which took place on the 20th of January last, in the 84th year of his age. Sir John Soane was profoundly acquainted with the great prin- ciples of his art, and many of the interiors as well as exteriors of his buildings are remarkable for skilful construction and for rich and harmonious effects; but he was unfortunately disposed, in some cases, to seek for novelty rather in new forms and decorations of architec- tural members, than for originality in the combination of those which have been sanctioned by the concurrent voice of the most cultivated of ancient nations and the greatest masters of modern art ; it is for this reason that many of his works appear somewhat capricious and extravagant, and fail to produce that undefinable feeling of pleasure and satisfaction which always attends the contem- plation of those great productions of architecture which have been celebrated for correct proportions, or for beautiful and appropriate decoration. In connexion with this distinguished professor and patron of art, I feel myself called upon to allude to the name of the venerable Earl of Egremont, whose very recent loss we have to deplore. He was a nobleman distinguished by his active yet discriminating be- nevolence, and by his princely use of a princely fortune ; but it is as a judge and patron of art that his loss will be most severely felt beyond the precincts of his own family and the numerous poor who were the immediate partakers of his bounty. He was equally ju- dicious in the selection of subjects for artists to execute, and liberal in rewarding them when done. Mr. J. D. Broughton, Surgeon of the Life Guards, had served with great distinction as a medical officer during a great part of the Peninsular war and at Waterloo. He was an eminent physiologist, and devoted a great portion of his time and attention to the study and improvement of the science of medical jurisprudence, and more Anniversary of 1 8 3 7. Address of the President. 279 particularly to experiments on the effects of poisons, and to the best and most unerring tests for detecting their presence after death. His death, which followed a serious operation, rendered necessary by a long-neglected accident, was deeply lamented by a large circle of friends, by whom he was equally respected and beloved for his great professional talents and for his honourable character. Mr. John Davidson, the last known victim to the cause of African discovery, was formerly a partner in the house of Messrs. Savory and Moore, the well-known chemists, but was induced to quit it in 1826, partly with a view to gratify his passion for foreign travel, and partly from other causes. He afterwards visited North and South America, India, Palestine, Turkey, Greece, Italy, Germany, and France ; and the lectures which he gave at the Royal Institu- tion and elsewhere, after his return, on the pyramids of Memphis and Mexico, on Thebes and the temples of Egypt and Jerusalem, afforded a sufficient proof both of his activity and of his accurate observation. The spirit of enterprise and travels, when once ex- cited, is not easily allayed, and Mr. Davidson devoted himself, almost from the period of his return to this country, to a course of preparation for a' journey to Timbuctoo, which had already proved fatal to so many adventurers. He was accompanied on this journey by Abu-Bekr, an enfranchised African slave, who had been a prince in his own countrj^ when young, and was well acquainted with the Arabic language. He had penetrated from Wadnoon to within twenty-five days' journey of Timbuctoo, when he was murdered by the El Hareb tribe, who were suspected to have been hired for that purpose by Moorish merchants, who, from not being able to under- stand or conceive the real motives of such an undertaking, con- ceived that its success would be injurious to their interests. Mr. Davidson was a man of great activity and strength, in the full vi- gour of life and health, and able to endure the severest labours and privations ; but personal accomplishments the most calculated to se- cure success in ordinary attempts of this nature, serve only to aug- ment the suspicion and to stimulate the cruelty of those savage tribes, who tyrannize over these inhospitable and almost impenetrable regions, and who are described by his companion, Abu-Bekr, " as full of envy at a stranger's goods ; they lie in wait to plunder him of every thing, as a lion lieth in wait for the cattle ; they have no mercy on the stranger ; even if a stranger were to strip off his skin and to give it to them, they would seize upon it." The only Foreign Members whom the Society has lost during the last year are Dr. Adam Afzelius, of Upsala, and Professor Morichini, of Home. Dr. Adam Afzelius was born at Larg in West Gothland in 1750, and was one of the last surviving pupils of Linneeus. In 1777 he was appointed Reader of Oriental Literature, and in 1785 Demonstra- tor of Botany in the University of Upsala, and he made his first ap- pearance as an author by the publication of a short supplement to the Flora Sttecica of his master, in the Transactions of the Academy of Stockholm for 1787. In the years 1792 and 1794', he made bo- 280 Royal Astronomical Society, tanical expeditions to Guinea and Sierra Leone, and a considerable part of the collections which he formed in those countries passed subsequently into the herbariums of Sir Joseph Banks and Sir James Edward Smith. In 1797 he was made Secretary of Legation to the Swedish Embassy in this country, and in the following year he was elected a Foreign Member of the Royal Society on the ground of his great knowledge of botany and zoology. Upon his return to his own country, he became Professor of Materia Medica and Diaetetics, at Upsala, situations which he retained for the remainder of his life. He was the author of a learned paper in the Linnean Transactions for 1791 on the genus Trifolium*, and also of two works entitled Hemedia Guinensia and Stirpium in Guinea medicinalium species : he edited likewise the botanical Correspondence of Linnaeus. He was a botanist of great learning and acquirements, and highly esteemed by the leading founders of the Linnean Society ; but I am unable to connect his name with any considerable advancement in natural knowledge. Professor Morichini, of Rome, was elected a Foreign Member of the Royal Society in 1827, and is chiefly known for his experiment on the magnetizing influence of the violet rays in the solar spectrum. His experiment was repeated by Configliachi at Pavia, and by Berard at Montpellier, without success, and in consequence doubts were expressed of the accuracy of his results, which appeared to be finally removed by the successful repetition of it by our justly cele- brated countrywoman Mrs. Somerville, in the summer of 1 825. I am not aware however that any other philosopher has succeeded in a similar attemptf . [To be continued.] ROYAL ASTRONOMICAL SOCIETY. Nov. 10, 1837. — Among the numerous presents to the Library, laid on the table this evening, was the magnificent work of Struve, on the micrometrical measures of double and multiple stars, made at the Dorpat Observatory, from 1824 to 1837, with Fraunhofer's great telescope ; accompanied with a Report to the President of the Impe- rial Academy of Sciences at St. Petersburg, detailing the nature of the work, and the principal results which, had been deduced. The following communications were read : — On the Parallax of a L)Tae. By the Astronomer Royal. The author commences with stating, that after the discussions as to the sensible annual parallax of a Lyrse, which have been con- ducted with so much ability and ardourj, and in which the opposite * Prof. Afzelius was the author of another paper in the Linnean Trans- actions, vol. iv., entitled '* Observations on the genus PausuSj and Descrip- tion of a new Species.^' — Edit. t See Phil. Mag,, First Series, vol. liii. p. 269 : Mrs. Somerville's paper was given in vol. Ixviii., p. 168. I Mr. Pond's paper on the Parallax of ec Lyrae was inserted in Phil. Mag., First Series, vpl. Ixii. p. 292. The Astronomer Royal on the Parallax of a Lyrcc, 281 opinions have been founded on so many well- chosen observations, it would be useless now to express an opinion, except it were based on more numerous and more excellent observations, reduced with greater attention to accuracy than in former instances. He states , therefore, that the whole number of observations employed was 184, made entirely in the year 1836, and, in general, distributed uni- formly over the year (with the exception of the month of February, in which no observations could be obtained) : that the obsenations were divided equally between the two circles, and that nearly half of them were by reflection : that the telescopes have been in the same position on the circle during the whole year, with the exception of a few days at its commencement : that the zenith points have been determined independently every day ; and that the six microscopes of each circle have been read for every one of these observations, as well as for every observation assisting to determine the zenith point. He then states, as an innovation on the practice of Mr. Pond, that a correction for runs has been introduced, determined from examinations made every week ; the necessity for which arises from the circumstance that it is practically impossible to adjust the microscopes, so that five turns of their micrometers shall correspond exactly to the interval between two divisions on the limb, and whose importance in this investigation depends on its periodic character varying with the temperature, and (with some regularity) with the season of the year. The author states his belief that, with this cor- rection, the only appreciable defect of the mural circle is removed ; and that it is thus superior to any other instrument which has been employed in this investigation. The author then gives the results in the form of equations, founded each on the mean of a group of observations ; each set of observations (Troughton, by direct vision ; Troughton, by reflection ; Jones, by direct vision ; Jones, by reflec- tion) being divided into four groups, and an equation being obtained from each group, expressing the polar distance in terms of the cor- rection of the coefficient of aberration, and the coefficient of paral- lax. Taking the mean of the results, with each circle, by direct and reflected vision, the coefficient of parallax from Troughton's circle appears to be -f 0"*2 ; and that from Jones's circle — 0"*1. The author concludes from this, that the annual parallax is too small to be sensible to our best instruments. The coefficient of aberration (20" "3 6) appears, from the observations with Troughton's circle, to require no sensible alteration ; from the observations with Jones's circle, it appears to require the increase 0""4. The north polar di- stance of a Lyrse, for Jan. 1, 1836, deduced from the whole of the observations, is 51° 21' 53"-73. The constant quantity of the Moon's Equatorial Horizontal Pa- rallax, deduced from observations made at Greenwich, Cambridge, and the Cape of Good Hope, in 1832 and 1833. By Professor Henderson, Astronomer Royal for Scotland. An abstract of this paper will be found in the Society's "Monthly Notices " ; but it is proper to state here, that the most probable 282 Royal Astronomical Society, value of the constant of parallax deduced from Mr. Henderson's ob- servations is 57' 1"'8 ; the corresponding value of the moon's mass is —^ ; and that of the coefficient of lunar notation 9"' 28. List of Moon-culminating Stars observed at the Royal Observa- tories of Greenwich and Cambridge, in the month of June, 1837. This list also will be found in the Monthly Notices. December 8, 1837. — The following communications were read: Observations of the Solar Eclipse of May 15, 1836, at the Obser- vatory of San Fernando. By M. Cerquero. Moon Culminating Stars observed at San Fernando in 1835 and 1836. By M. Cerquero. List of 285 Stars of the Society's Catalogue which are Double. By Mr. Holehouse. On a very ancient Solar Eclipse observed in China. By R. W. Rothman, Esq. This is the famous eclipse which has been so much discussed by the Jesuit Missionaries, De Mailla and Gaubil, which has l)een vaunted as an irrefragable proof of the antiquity of the Chinese empire and science ; and for failing to predict which, the unluckly astronomers. Ho and Hi, were punished with death. The particulars are given in the Histoire Generate de la Chine, translated from the Chinese, by Moyriac de Mailla, and the Ohserva^ tions Mathematiques, &c., published by Souciet. It seems that a cer- tain Chinese history, the Chou King, said to be of the highest anti- quity, but without date, contains a statement to the effect that, to- wards the beginning of the reign of Tchong-Kang, on the first day of the third moon of autumn, there was an eclipse of the sun in the constellation Fang (Scorpio). Another chronicle, less ancient, but of which the date is still anterior to 460 b.c, states that the eclipse took place in the fifth year of Tchong-Kang, on the first day of the ninth month, and adds cyclic characters for the day and year, correspond- ing, according to some of the chronologers, to October 13, 2128 b.c. The chronologers, however, are not agreed with respect to the year of the eclipse. Some refer it to 2159 B.C.; others, as just stated, to 2128 ; and Gaubil, by whom the eclipse was calculated, and who cites the calculations of three other Jesuits in proof of the accuracy of his own, says it took place on the 1 2th of October, in the year 2155. Freret, on the authority of the calculations of Cassini, refers it to the 23rd of September, 2007. On account of these discrepan- cies, and the uncertainty occasioned by the imperfections of the tables employed in the former calculations, Mr. Rothman undertook to cal- culate the eclipse anew, from the more accurate tables now existing. He states, that for the sun he employed Delambre's tables, and for the moon the elements of Damoiseau ; and that he has found the eclipse took place on the 13th of October, 2128 b.c, the instant of the greatest phase being 12^ 8"^ 47^ mean time from midnight at the place of observation, and the magnitude 10'5 digits ; — ^a result agree- ing entirely with the indications of the Chinese chronicle. The reader may see the arguments for and against the authenticity M. Reich on the mean Demity of the Earth, 283 of this observation, in Delambre, Histoire de VAstronomie Ancienne, torn. i. p. 350, et seq. On the Repetition of the Cavendish Experiment, for determining the Mean Density of the Earth. By the President. It is well known to most of the Members of the Society, that the Council has long had it in comtemplation to repeat the celebrated and interesting experiment of the late Mr. Cavendish for determining the Mean Density of the Earth, and that a Committee was appointed more than two years ago to consider of its practicability. The object is now in a fair way of being accomplished. Her Majesty's govern- ment having been jileased to "grant the sum of 500^. towards defray- ing the requisite expenses. The apparatus is, at this moment, in the course of being erected, and as soon as it is completed, the ex- periments will be commenced. During the time, however, that the subject has been in agitation in this country, it appears that the same experiment has been un- dertaken by M. F. Reich, Professor of Natural Philosophy in the Academie des Mines, at Freyberg, in Saxony. The details of the experiment are given in a memoir, read by him at the German Sci- entific Association, which met at Prague in the month of September last. Whether this memoir has yet been published, the Author has been unable to ascertain ; but an abstract of it has appeared in some of the foreign journals, from which the following particulars are collected. The method followed by M. Reich appears to have been exactly the same as that of Cavendish. The apparatus was erected in a large room under the buildings of the Academie, the windows of which were carefully closed up, and other precautions taken to pre- serve a uniform temperature. The torsion-balance, carrying two small leaden balls at the extremities of its arms, was encased in a wooden box, of dimensions just sufficient to allow room for the oscillations. To avoid currents of air, the oscillations were ob- served by means of a ^telescope fixed outside the door of the room in which the apparatus was placed, and directed on a mirror at- tached to the extremity of the arm, and illuminated by a lamp, also placed outside the room. The masses, whose attraction was to be measured, were spheres of lead, weighing 45 kilogrammes, or 695,061 grains. They were suspended by brass rods to a beam, moveable about a vertical axis ; and which by means of cords and puUies, the observer, without entering the room, could bring into any required position, with reference to the direction of the arms of the torsion-balance. It was found, however, most convenient, to use only one of the spheres. The principal correction required is for the moment of the arm of the balance. This was computed by a method similar to that which was employed by Gauss for de- termining the moment of inertia of his magnetic bars. Nearly two years were consumed in the necessary preparations ; but when completed, M. Reich was enabled to perform the experi- ments during the three months of June, July and August, 1837. Each observation required the determination of three quantities :— 284? Geological Society, the distance of the centres of the large and small spheres, the time of the oscillations, and the deviation of the arm of the balance. The distance varied from 6*62 to 7 49 inches ; the duration of the oscil- lations, from 6"™ 4P, to 6"^ 50«; and the deviation from '236 to •315 of an inch. The greatest source of error is in the determina- tion of the deviation ; the position of the arm being subject to some anomalous variations caused, probably, by slight currents of air in the interior of the wooden case. This source of error could only be eliminated by increasing the number of observations ; but the dif- ferences of the partial results actually obtained were so small that the mean result may be regarded as sufficiently approximate. The number of observations was 57. The mean of the whole gives the density equal to 5*44, a result which is almost identical with that of Cavendish. M. Reich also used for the attracting mass a sphere of cast-iron, of the same diameter as the leaden one, and weighing 30 kilogrammes, or 463,373 grains. Five observa- tions with this sphere gave the density = 5 '43. The public will look with much interest for further particularsi respecting these experiments, in order that they may be examined more in detail. The only innovations on the method of Cavendish appear to have consisted in using only one of the great spheres in the same experiment, and in the mode of observing the deviation of the arm of the balance. The arm itself appears to have been nearly of the same length as that used by Cavendish, but we are not in- formed of its weight, nor of the weight of the small balls. The large spheres, however, were much inferior to those of Cavendish, their diameters being only 7|- inches, and weight less than 2-7ths of those used by Cavendish. The employment of the cast-iron sphere is a new feature in the experiment, but it does not appear that the small balls were changed. Mr. Baily concludes with remarking that, though these experi- ments are, on the whole, confirmatory of the general result obtained by Mr. Cavendish, they do not interfere with the plan the council of the Society had in contemplation, which was not merely to repeat the original experiment in a precisely similar manner, but also to extend the investigation by varying the magnitude and substance of the attracting masses, by trying their eff'ect under considerable dif- ferences of temperature, and by other variations that may be sug- gested during the progress of the inquiry. A Catalogue of Moon- culminating Stars observed at Greenwich, Cambridge, and Edinburgh, in the months of July, August, and September, 1837. This catalogue appears in the Monthly Notice of the Society, No. 10. of vol. iv. GEOLOGICAL SOCIETY. Nov. 15, 1837. — A Letter from Walter Calverly Trevelyan, Esq., F.G.S., to Dr. Buckland, V.P.G.S., on " Indications of Recent Elevations in the Islands of Guernsey and Jersey and on the coast of Jutland, and on some Tertiary Beds near Porto d'Anzio" was first read. Geological Society, 285 On the shore near the point where the road descends towards the rock or islet of Lihou, on the east of Guernsey, may be seen a sec- tion, in which, above the present high-water mark, the granite rock bears evident marks of having been worn by the action of the waves, previously to the deposition on it of a bed of gravel, which now covers the granite and fills up the inequalities of its surface. The gravel, which is firmly bound together by a ferruginous sand, consists of pebbles of the neighbouring rocks, also of chalk flints, some not much rounded, and extends to about 8 feet above the present high- water mark, and apparently ranges a little inland. On the gravel is a bed, about 3 feet thick, of disintegrated granite, mixed with angu- lar fragments of that rock, and covered by the surface soil. On the N. W. of the island, near Fort Doyle, there occurs, near the shore, a similar bed of gravel, aboutSfeet above high-water mark, rest- ing on the surface of the syenitic rocks of a low cliff, which bears evi- dent signs of disturbance from subterranean agency. Here the gravel, previously lying upon the rock, has fallen into and filled up the fissures which have been created, and has even been forced under some parts of the rock, which seem still to be in connexion with their original masses. In St. Catherine's Bay, Jersey, the author also observed a section which affords evidence, though to a small extent, of an elevation of the old beach. The author then calls attention to a fact regarding the elevation of land bordering on the Baltic, which he conceives has not before been noticed. On the coast of Jutland, near Frederickshavn (not far from the Scaw), the author observed, that the country abounded with sepulchral tumuli, except on a low and extensive tract bordering the sea, where none occurred. He therefore supposes, that the latter has been elevated since the period when the above mode of burial was disused in that country, which he believes was about the eighth or ninth century*. The author concludes his letter with some account of a visit paid to Porto d'Anzio (the ancient Antium), and of some extensive ter- tiary (pliocene) beds found there. These deposits form cliffs about 50 feet high, and contain numerous shells, but little altered, and apparently of the same species as those now inhabiting the neigh- bouring sea. Pecten Jacobmis and P. opercularis, not at all water- worn, are the most numerous, often forming considerable beds in a loose or indurated calcareous sand. The dip of the strata is consi- derable and to the south-east. The deposit may b^ traced some way into the interior, and to elevations of 200 or 300 feet above the sea, where there are quarries worked in ancient times; and on the east to Nettuno, about a mile and a half from Antium, at which point the upper beds rise to the surface. Passing thence to the west, and beyond Antium, lower beds successively crop out for about a mile, • A similar inference was drawn by Dr. Forchhammer with respect to Bornholm in a paper "On some changes of level during the historical period in Denmark", read May 31, 1837. See Proceedings of Geological Society, vol. ii. p. 555, or L.& E. Phil. Mag., vol. xi. p. 310. 286 Geological Society, when the lowest, a sandy clay, appears, and continues for some di- stance, nearly horizontal. It is overlaid in part by a bed of sand, containing a layer of gravel in the lower part, and the two strata form together a cliff 30 or 40 feet high. In the clay the fossils are not so abundant, but are apparently of the same species as in the upper beds. About two miles from Antium, a thin bed of tertiary sandstone, con- taining abundance of the same fossils, begins to make its appearance resting on the clay, and it gradually increases in thickness to about 20 feet; but then gradually thins out again to the west, extending altogether between a quarter and half a mile. Below it, 20 feet of clay are exposed, and above it, a ferruginous sand, about 15 feet thick, through the lower 6 feet of which, some fine siliceous gravel is interspersed, like the flint gravel of the plastic clay of England, and agreeing in character with that of the present beach. The masses which iiave fidlen on the shore, from above, look, when washed by the waves, exactly like a rock abandoned by the sea for merely a few tides, in consequence of the fresh appearance of the shells and corals with which they are covered. In the tertiary rock of the neighbourhood, specimens were met with, in which the calcareous matter of the shells had been replaced by sulphur, and the author conceives the change to have been ef- fected through the percolation of water, of which a stream exists, con- taining a strong solution of sulphate of iron with excess of acid. Near this spot, called Solfarata, are some pits, apparently in the upper sand, and from which sulphur is dug in winter. A letter from Sir Robert Smirke was then read, forwarding an- other from Mr. Edge to himself, in which the latter states, that when engaged in erecting some works in the neighbourhood of St. Peter's, Guernsey, he found it necessary to have a well dug. At the depth of 45 feet from the sui^ace, the workmen came to a block of granite, which they were forced to blast, and ascertained to be 6 feet in thickness. A few feet beneath the granite, they were surprised at finding a small quantity of peat, with several pieces of fossil timber (specimens of which have been sent to the Society) in the state of bog-wood, and conceived to be oak. The reading of a paper was afterwards commenced " On the Geo- logy of the Eastern Portion of the Great Basaltic district of India," by J. G. Malcolmson, Esq., F.G.S., of the Madras Medical Establish- ment. Dec. 16, 1837. — Mr. Malcolmson's paper on the eastern portion of the Great Basaltic district of India, begun on the 15th of Novem- ber, was concluded. The principal objects of this paper are to describe the eastern boundary of the great basaltic formation of India, with its associated stratified deposits, and to arrive at a proximate conclusion respecting the age of the basalt. Extent of Country. — The region noticed generally in the paper, is included between the 14th and 21st degrees of north latitude, and the 75th and 82nd degrees of east longitude ; but the districts more particularly described, are those watered by the Pennar river (lat. 14°), Geological Society, 287 the pass of the Sichel hills, near Neermul (lat. 19° 18', long. 79° 33'), and the plains extending from the northern base of that chain to Nagpoor. Physical Features of the Country. — The region forms part of the great, elevated plateau which includes all the countries to the south of the Nerbudda (lat. about 22° N.), and connects the provinces watered by the southern branches of the Ganges with the Deccan. It is traversed on the north by the Sichel or Shesha hills, locally called the Neermul range, which extends from the junction of the Wurdah and Godavery rivers (lat. about 18° 48', long. 80°), till lost in the gradual rise of the country near Lonar (lat. 20°, long. 76° 30'). The principal rivers which traverse the region are the Wurdah, the Godaver}% the Kistnah and the Pennar. The first flows north and west of the Sichels, the second south of that chain, till its waters unite with those of the Wurdah. when it takes a south-easterly di- rection to the Indian ocean. The Kistnah flows nearly W. and E., between the parallels of 16° and 17° ; and the Pennar traverses the southern portion of the region (lat. 14° 30'). In the part watered by the last river, a marked feature is presented in the horizontal sum- mits of many of the ranges of hills, which appear to have been once connected, though they are now separated by extensive plains. Geological Structure. — The formations consist of granite, gneiss, mica and hornblende slates, trap, argillaceous limestone, red sand- stone, with diamond breccia, and tertiary freshwater strata. The granite forms apparently the base of the country, and the trap pene- trates all the formations, including the granite and the freshwater beds. In addition to these regular deposits are considerable accu- mulations of travertine and kunkur, which are scattered over the whole surface of the country. Granite. — This rock is frequently displayed in all the rivers of southern India, and is occasionally visible as the substratum of the other formations. In the table-land of the Mysore it attains an ele- vation of 3000 feet above the sea. In the Deccan, between the Kistnah and the Godavery, it is traversed by greenstone dykes, sometimes porphyritic, and ranging, for the greater part, from S. by E. to N. by W., a direction not very difl^erent from that of several of the basaltic mountains in the northern part of the region ; but on approaching the Godavery, from the south, the granite is penetrated by dykes, which strike N. and S. Beyond Nagpoor the granite has burst through the red sandstone, which is converted into quartz rock; and, still further north, granite veins intersect the argillaceous limestone, which has lost its stratified structure. Granite veins also penetrate the neighbouring hills of gneiss and mica slate. Gneiss, Mica and Hornblende Slates. — ^These formations appear to be of limited extent. Hornblende slate was noticed by the au- thor only in the neighbourhood of Deemdoortee, 20 miles E. of Neermul, where it contains the magnetic iron ore used in the manu- facture of Damask steel. Gneiss and mica slate are mentioned only at the locality alluded to above, a few miles N. of Nagpoor. Trap, — Mr. MalcoUnson distinguishes the trap of the dykes from 288 Geological Society, that which constitutes the great basaltic ranges, by the absence of olivine in the former, though it is common in the latter. The great masses of basalt are also distinguished by being amygdaloidal and more crystalline. When en masse the trap overlies the granite, as well as the stra- tified deposits. In the form of veins it traverses the granite, lime- stone, and sandstone, and the freshwater strata are often imbedded or entangled in it. In sinking a well near Hutnoor, (lat. 19°38'N., long. 78°30'E,) seams of pure white, pulverulent limestone were found beneath layers of basalt, and calcareous depositions appear to accompany the formation almost universally. With recpect to the minerals con- tained in the amygdaloid s, Mr. Malcolmson is of opinion, that they have not been produced either by infiltration or sublimation, but by molecular attraction, because calcareous spar is much more rare than siliceous minerals, though carbonate of lime abounds throughout the basalt. Argillaceous Limestone . — Organic remains have not been noticed in this rock. It consists, in the lower part, of thin strata of compact blue or white limestone, and generally, in the upper, of blue, red, green and white schists, or slaty clay. Siliceous matter occurs in both the limestone and schist. Where the formation is in contact with the trap, the limestone is sometimes crystalline, and loses its stratified structure ; and at the Pindee Ghat, in the Sichel Hills, the argillaceous and siliceous ingredients appear to have separated, and the latter to have collected in bands, having partly the aspect of chalcedony, and in black chert. In some districts the limestone is cavernous, and it is often penetrated by circular cavities, which, the author conceives, were formed by the extrication of gaseous fluids, in the same manner as similar cavities are now produced in the mud by the escape of carbonic acid gas. A jointed structure, dividing the beds into rhombs, prevails in the limestone, the schist, and the overlying sandstone. The strata are often inclined, apparently the result of dislocation. At Jumulmudagur (lat. M" 50', long. 78^ 30') the limestone con- tains layers of muriate of soda ; and Mr. Malcolmson is of opinion, that the salt which is found in the alluvial matter, is obtained solely from this formation, as he did not discover a trace of it in the sand- stone. The limestone and shale are well displayed in the Pennar district, also between the northern foot of the Sichels and Nagpoor ; and the author has no doubt that they belong to the same system of strata as the limestone of Bundelcund, described by Major Franklin*, though the red sandstone of that country is stated to underlie the limestone, while in the region examined by Mr. Malcolmson it overlies. Red Sandstone. — This formation is distinguished by containing the breccia in which are situated the diamond mines of Golconda, * Geol. Trans., 2nd Series, vol. iii., part i., p. 191 et seq., also Asiatic Researches, vol. xviii. p. 24, et seq. An abstract of Major Franklin's paper appeared in Phil. Mag. and Annals, N.S., vol. iv. p. 294. Geological Society. 289 on the banks of the Kistnah, and those on the banks of the Pen- nar. Where the sandstone rests upon the limestone schist, a gra- dual passage occurs. The rock is more or less compact, and its prevailing colours are red and white. The diamond breccia is con- sidered by the author, as only a variety of the sandstone in which • fragments of older rocks have been imbedded. Ninety miles S.W. of Nagpoor traces of coal were noticed, and in the hill of Won (lat. 20° 6', long, nearly 79°) Mr. Malcolmson found the cast of ap- parently a hollow vegetable, the only trace of an organic body ob- served by him. The sandstone, as already noticed, partakes of the same jointed structure as the subjacent limestone. It is penetrated as well as overlaid by trap, and near Nagpoor veins of granite have converted it into quartz rock. In the district drained by the Pennar, the sandstone attains the height of 3000 feet, forming the horizontal or flat summit of the mountains ; but in the same district, and at no great distance, it occurs on a level with the plain. Tertiary Strata. — Masses and fragments of differently coloured chert, a tough, white, argillaceous stone, and a greyish blue crystalline rock, all containing freshwater shells, either project from the trap in which they are entangled, or are scattered over its surface for consider- able areas in the Sichel hills. In a precipitous descent, on the northern flank, the author also noticed ahorizontal bed of white limestone, 12 ft. thick, containing freshwater shells and resting on granite, but covered by basaltic debris. The organic remains, brought to Europe by the author, have been examined by Mr. James De Carle Sowerby, and as- certained to belong to two species of Gyrogonites, two of Cypris, two of Unio, with numerous specimens of Paludinse, Physse, and Limneae. The greater part are siliceous casts, but some retain their original calcareous matter. Silicified portions of palm woods, and fragments of vegetables, in a charred or carbonized state, also occur. In ac- counting for the diiferent state of preservation of the shells, Mr. Malcolmson suggests, that the lime being in some instances retained, may be explained on the supposition, that the shells were perfectly dry at the time they were acted upon by the basalt. With respect to the origin of this singular rock, the author is of opinion that the basalt, when it was irrupted, changed the features of the country, and, destroying pre-existing lakes, entangled in its substance the debris and shells which had accumulated at the bottom of the bodies of water, and converted the loose sand into chert or si- liceous rock. Of the age of the formation, he does not pretend to offer a precise opinion. None of the shells have been identified with those now inhabiting the rivers of India ; and he is, therefore, in- clined to consider them as extinct, and to refer them to the tertiary sera. This fossiliferous chert was noticed by the author over a surface extending 140 miles N. and S. ; but shells considered to be identical with those collected by him, were found by Dr. Spilsbury, iB miles E. from Jubalpore (lat. 23° 45' N., long. 78° 53' E.), in a block of in- durated clay, resting on basalt* ; by Dr. Voysey, in the Gawilghur • .Journal of the Asiatic Society of Bengal, vol. ii. pp. 205 and 583 PhU, Mag. S, 3. Vol. 12. No. 74. March 1838. 2F 290 Geological Society. range (near the table-land of Jillan)* ; by Dr. Spry, in a bed of limestone, overlaid by trap, near Saugorf (lat. 24° 15' N., long. 79° E.) ; by Dr. Voysey, in a siliceous rock in the hills of Medcondah and Swalpigapah south of the GodaveryJ ; also at Jirpah, N. of the sources of the Taptee (about lat. 22° N., long. 78°E.)§. Comparative Age of the Formations. — On this head few observations are necessary. North of Nagpoor the granite has been shown to be more recent than the sandstone. The trap in the form of veins pene- trates the granite, and affects, en masse, the limestone and sandstone, and entangles in its substance the fossiliferous chert. If therefore, the last belongs to the tertiary period, part at least of the basalt of the Sichel hills, forming the eastern boundary of the great basaltic re- gion of India, cannot be assigned to one more ancient. Of the age of the limestone and sandstone Mr. Malcolmson offers no positive opinion, but he objects to their being considered the equivalents of the new red sandstone and lias of England || , because their order of superposition in the district examined by himself, is inverted, the limestone underlying the sandstone; and he only ventures to suggest, that they may belong to the older secondary, or younger transition systems. Travertine and Kunkur. — Springs charged with carbonate of lime prevail throughout the country, and in the bed of some of the rivers, calcareous matter is so abundantly deposited as to cement the peb- bles into a hard rock. " It is impossible," says the author, •* to ex- amine these accumulations without immediately perceiving the origin of the nodular limestone or kunkur, which is so extensively distri- buted in India." Thermal Springs and Mineral Waters. — At Kair (lat. 19° 55', long. 78** 56') and Urjunah, springs having a temperature of 87°, and charged with carbonic acid gas, issue through the limestone ; and one, at the former locality, contains also a little muriate of soda, a minute quantity of sulphate of lime, and much carbonate of lime. At Byorah (lat. 17° 57', long. 80° 20') is a spring, the tem- perature of which is 110°; and at Badrachellum, (lat. 17° 43', long. 80® 79') one possessing a temperature of 140°, and containing sulphuretted hydrogen, and sulphates and muriates of soda and lime. A minute description is given of the mineral waters of the Lonar Lake, (lat. 20°, long. 76° 30') and of the natron which is deposited in a layer beneath its muddy bottom. The water of the lake is clear, its specific gravity is 1027*65, and it has no unpleasant smell ; but the mud at its bottom is highly charged with sulphuretted hydrogen. The salt under the mud accumulates slowly, and is extracted only • Asiatic Researches, vol. xviii. p. 192. f Journal of the Asiatic Society of Bengal, vol. ii. pp. 376, 639. I Asiatic Researches, vol. xviii. p. 193, and Journal of the Asiatic So- ciety of Bengal, vol. ii. p. 304. § Journal of the Asiatic Society of Bengal, vol. i. p. 247. II See Major Franklin's memoir on Bundelcund, &c., in the Geol. Trans., 2nd ser., vol. iii. p. I9I, etseq., also Asiatic Researches, vol, xviii. p. 24, €t ieg. ; and Phil. Mag, and Annals, N.S., vol. iv. p. ^94. Meteorological Society. 291 once in several years. It consists of carbonic acid 38*, soda 40*9, water 20*6, insoluble matter '5, and a trace of a sulphate ; and thus corresponds in composition with the Trona, or striated soda from the Lakes of Fezzan, analyzed by Mr. R. Phillips*, and approaches somewhat nearer to the equivalent numbers of the sesquicarbonate established by that analysis. The water of the Lonar lake contains, besides a little potash, muriate of soda 29 grains, sesquicarbonate of soda 4*2 nearly, and sulphate of soda '1, in 1,000 grains of water. No lime was detected in it, nor any magnesia. The absence of the former Mr. Malcolmson says, is easily accounted for, as the sesquicarbonate of soda and the water itself precipitated the sulphate and muriate of lime, notwithstanding the mutual de- composition they undergo when in a semifluid state. In account- ing for the production of the natron, he adopts the theory of Ber- thollet for the formation of that salt in the lakes of Egypt, viz., a mutual decomposition of the muriate of soda and carbonate of lime, when in a pasty state; but as the natron of Fezzan and the Lonar lake contains half an equivalent more of carbonic acid than can be furnished by carbonate of lime, he proposes a modification of that theory, and suggests that the carbonic acid by which the lime is held in solution in the mud, furnishes the acid, and perhaps indicates the existence of an unstable sesquicarbonate of that substance. * ' Where- ever," adds the author, " 1 have met with natron, or obtained de- tailed accounts of its occurrence, muriate of soda and carbonate of lime existed in the soil, and the natron was found on the surface of the moist earth or mud." METEOROLOGICAL SOCIETY. Jan. 9, 1838. — A paper on the meteorology of the Island of Teneriffe, lat. 28° 37' N., long. 16° 15' W., by Lieut. Grey (Asso- ciate Member of the Society) in charge of the Australian expedition, was read. " The island of Teneriffe," says Lieut. Grey, " is of volcanic origin; and as its famed peak is at the present moment, and has been siijce the island was known to Europeans, in a state of solfatara, I en- tertained a hope that if a series of observations had been made they might possibly throw some light upon the influence that volcanic action exercises upon atmospheric phsenomena." Lieut. Grey ascertained that the late Dr. Saviiion of Laguna, a town on the island of Teneriff^e, about 1 800 feet above the level of the sea, and three miles from the shore, had made a series of ther- mometrical observations during a period of eight years (from 181 1 to 1818 inclusive) without an interruption of a single day, from which observations a mean of the whole year was obtained of 62'^" 75 Fahr., and 68°-75 Fahr. the mean of July, the month of Lieut. Grey's visit to the island. Lieut. Grey immediately caused two sets of observations to be * Journal of the Royal Institution, vol.vii. p, 294. 2F2 292 Intelligence and Miscellaneous Articles, made on board H. M. ship Beagle at Santa Cruz, the vessel lying at the time a quarter of a mile from the shore. One set was made in the cabin of Captain J. Wickham, R.N., and the other upon the quarter deck in the shade. During the stay of the vessel, v^rhich was only five days, the mean temperature (from these two sets of observations, taken three times a day, and in the unusually warm month of July,) was found to be 76°Fahr., a difference of less than eight degrees, which serves fully to corroborate Dr. Savinon's obser- vations, if we consider that one series of observations was made at an altitude of 1 800 feet, and through an uninterrupted period of eight years, and the other at the level of the sea, and during a pe- riod of only five days. The quantity of rain which fell at Teneriife in 1812 was 19*33 inches, of which 5*24 inches fell in January in twenty-four hours. In 1813, 25-22 inches. In Dr. Savinon's MSS. the following particulars are recorded of a tempest of wind and rain which visited the Canary Islands in the night between the 7th and 8th of November 1826. In the Island of TenerifFe alone (though much damage was done in all the islands) there were 311 houses destroyed and 114 houses ruined, 243 per- sons killed, and 1042 animals destroyed. Thus may be seen the fury with which these storms sometimes rage*. XLV. Intelligence and Miscellaneous Articles. ** In order to. meet any objections which may be made by those who have had no opportunity of examining these subjects more closely, I will just remark, en passant, that Corda's- history of the develop- ment of the Coniferce, \Acta Leop. Carol., xvii. pars 11,) coincides with Nature in the fewest points possible. It has caused me much pain, on account of some eminent men, who, having neither oppor- tunity nor time to examine into the case, and judging of others by their own conscientiousness, have allowed themselves to be led into a precipitate admiration. It is however, in this case, impossible to absolve them from all blame, since the memoir exhibits its character openly enough. For in the first page it is stated ; * Since the appear- ance of Robert Brown's writings, and his journey through Germany, every one is acquainted with the general results of his observations, so that I consider it superfluous to give, in this place, an accurate account of them.' Now it is well known that Mr. Brown had already published, in 1832, his discovery of the entrance of one or more pollen tubes into the micropyle ; and those persons who had • Further particulars of this tempest will be found in Mr. Alison's paper on the Peak of Teneriflfe, in Phil. Mag. and Annals, N.S. vol. viii. p. 26 ; and tables of meteorological observations made in the island at p. 439 — 441 of the same volume; in which also Mr. Alison discusses the decrement of temperature as observed in his ascent of the Peak, p. 248.— Edit. Intelligence and Miscellaneous Articles, 293 the good fortune to meet with Mr. Brown, during his journey through Germany (in 1833), will remember that he carried with him impreg- nated ovaria in spirits, and with his accustomed kindness showed the entrance of the pollen tubes into the ovulum to every one who took any interest in the subject. Notwithstanding this, Corda, a few- lines lower down, affects an unpardonable ignorance of this fact, in order to arrogate to himself a discovery which Amici (already in 1830) and Mr. Brown had made long before him Inconsist- encies are also evident in the figures. Fig. 14j for instance ; the embryonal sac is termed nucula, (should be nucleus,^ and the pollen tubes enter it in order to produce, by their emissions, heaven knows what kind of an imaginary figure. Fig. 22: here the embryonal sac is even called embryo (E), and the pollen tubes run around it. But it would be an herculean task to follow, step by step, this memoir. It will here suffice to observe that, with the exception of a few points of minor importance, everything almost surpasses the limits of pos- sible error, and does not in the least represent nature. I refer every one, who has even but little practice in such examinations, to na- ture herself, as the observations are not of the most difficult kind." ON THE DEVELOPMENT OF AN ELECTRIC CURRENT ACCOM- PANYING THE CONTRACTION OF THE MUSCULAR FIBRE. BY DR. J. L. PREVOST. About fourteen years ago we published, together with M. Dumas, a memoir on the muscular fibre, in which we determined that the contraction of the muscles was owing to the sinuous flection of the fibres ; we attributed the flection to the attraction of the nervous reticula, which placed at short distances from one another and per- pendicularly to the direction of the muscular fibres, approached each other when an electric current, emanating from the cerebro-spinal system, passed through them. Our observations having been made with a microscope inferior in goodness to those constructed by Amici, the true (Hsposition of the motive apparatus escaped us, and our assertion was considered an ingenious hypothesis deficient in the investigations requisite for its confirmation. Last summer I again resumed this subject with better means, and the following is one of the results which I obtained. If we observe the muscles of a frog with a magnifying power of four hundred, we perceive that they are composed of small cylinders, the diameter of which varies from five to twenty hundredths of a millimetre : these cylinders are connected with each pther by the cellular tissue, through which pass from one cylinder to the other the nerves and vessels. The fibres arranged thus parallel to one another, fix themselves, without separating, either to the tendons or to the aponeuroses which correspond to their extremities, the latter becoming round and disposing themselves in a small cavity placed on the tendon to receive them. ITie muscular cylinders, which we shall call fibres, are themselves composed of fibrillac, the diameter of which amounts to about ^tt 294? Intelligence and Miscellaneous Articles. 'to of a millimetre. They are placed in juxtaposition in the cylinder and united so closely that they appear to a common observer to form a homogeneous mass. At the surface of the muscular fibres just described, we perceive some rings, which surround their entire circumference like small ribands ; they are about ^^ of a millimetre apart from each other upon the fibre when it has lost all its irritability, closer on the living fibre : these rings belong to the enveloping membrane. If this latter becomes fissured longitudinally, which at times occurs, we observe the longitudinal fibrillse which form its mass, project in the fissure. The torn portions of the rings enable us to observe the ends of the reticula of which they are composed, and which cannot be seen in the normal state. On illuminating the muscular fibres by means of a mirror which reflects the light upon their upper surface, we observe that the nervous reticula which ramify on the muscle enter the linings of the fibres ; they thus appear to surround them similar to a series of circularly curved handles (ansae). The fibres in their quiescent state 'are not straight but slightly curved. When they act, every portion of the broken line which they present gravitates the one against the other, and the muscular contraction results from the shortening produced by this action. Such are the facts which every one may observe with a good microscope. Now let us apply to this highly remarkable anatomical arrange- ment, the doctrine of electric currents along the nervous reticula. It is evident that in this case each fibre becomes a little magnet with a flexible joint, the various parts of which would tend recipro- cally to attract each other, and would produce the eff^ect which we observe in the muscular contraction. But how detect these currents ? Hitherto they have been sought for only with the electrical multi- plier ; and we could not expect to find anything, as we had to do with closed circuits, and knowing at the same time that a divided nerve does not transmit any action. There was nothing left there- fore but the magnet that could point them out to us. To employ the magnetic needle was rather a difliicult affair : I had recourse to a diff'erent means. If a needle is placed in contact with some finely divided filings, such as we obtain from a file and soft iron, be it ever so slightly magnetic, it is perceptible from the arrangement which the particles of iron take at its surface : they plant themselves as little needles, which arrangement is easily perceptible with a magnifier. We must not confound this action with the attraction by which minute bodies remain attached to a bar with which they are touched. I ran a very fine needle not magnetized into the thigh of a frog, following the direction of the fibres ; the point projected and dipped into the filings. At the moment when I excited a violent contraction by wounding the spinal marrow, I saw the small particles of iron arrange themselves at the point of the needle as they do when it is magnetic ; they dis- appeared with the irritation of the muscle. By further investigating this phsenomenon I hope to render it very Intelligence and Miscellaneous Articles, 295 evident, and I should have deferred the publication of it until then, had not Professor de la Rive advised me to join it to the preceding obsei-vation, [Matteucci's Researches on the Torpedo, vide last and present Numbers of Phil. Mag.] and ]to record its date in our So- ciety.— Bibliotheque Universelle, November 1837. ON THERMO-ELECTRIC PH^INOMENA. BY CH. MATTEUCCl. Every time that a copper wire attached to a galvanometer and well-brightened (decape) is brought into contact with a second cop- per wire equally well cleaned, but heated by a lamp, we obtain an electric current, which passes from the hot end to the cold end. If we repeat this experiment with well-cleansed iron wires we obtain a contrary current which proceeds from the cold end to the-hot one; the same takes place also with zinc and antimony. This difference is observed whatever be the temperature to which one of the wires is heated. Now if instead of touching the wires we immerse them in pure mercury contained in two capsules united by a siphon full of mercury, one of which is hot, the other at the common tempera- ture, we have still a current, but which proceeds in the same direc- tion with copper, iron, zinc, and antimony. ITie mercury has here no influence by the thermo-electric currents which it might deve- lop, for the same results are obtained, if the two wires, always well- brightened, are immersed one after the other in the same heated cap- sule. It is therefore the action of the heat and of the air which pro- duces an alteration at the surface of the metal : and in fact, if a copper wire is heated exposed to the air in the flame of an alcohol lamp, and afterwards immersed in the mercury where the other wire is, the same difference is still observed as when the unequally heated wires were placed one on the other. I endeavoured to obtain thermo-electric currents with mercury by employing three capsules united by means of two siphons. In the outer capsules were plunged the wires of the galvanometer. I take away one of the siphons, heat the middle capsule and replace the siphon. I thus bring the hot mercury into contact with the cold. In this manner, however, I obtained but very feeble and doubtful deviations. Although the wire of the galvanometer was rather long, yet I doubt of there having been any development of thermo- electric currents on the mercury. An amalgam of bismuth (1 of bismuth, J of mercury) which is very crystalline, is endowed with a very considerable thermo- electrical power. If a heated plate of bismuth is touched with the two extremities of a galvanometer, very powerful currents are obtained. If the bismuth be melted and we still retain the two ends immersed in the fluid metal, the currents cease ; at times there are still some, but we at once easily perceive that either some of the bismuth has so- lidified, or that the two ends of the wire are unequally heated. With a larger melted mass in any sort of a vessel these currents entirely cease. If we then discontinue the heating, and allow the mass to become cold, at the instant when it solidifies the needle indicates 296 Intelligence a?id Miscellaneous Articles, deviations. The amalgam above-mentioned produces this i)haeno- menou exceedingly well. If the amalgam, although still capable of becoming solid, loses its property of crystallization from the presence of a lai'ger proportion of mercury, the phsenomenon no longer takes place. We obtain the same phaenomenon with antimony. One might be inclined from this to conclude that thermo-electric currents take place only on solid metals, especially since it appears to be well de- monstrated that it is by the effect of a chemical action that the contact of hot water with cold develops electric currents. — Biblio' thcque Universelle, November 1837. ON CETRARIN. BY M. HERBERGER. This name of cetrarin is given to the bitter principle of the cetra- ria or liverwort. M. Herberger first procured this product ; the pro- cess by which he obtained it is as foUoM^s : boil coarsely-powdered liverwort in four times its weight of alcohol, of specific gravity '883 for half an hour, and let it remain ; in order that no alcohol may be lost, it is strained and pressed ; to this liquor there is to be added, for each pound of liverwort employed, three drachms of hydrochloric acid, which is to be diluted with four times its bulk of water ; the mixture is to be allowed to remain for twelve hours in a stopped glass vessel ; the supernatant liquor, of a deep yellow colour, is then to be poured oiF from the abundant deposit formed ; this is impure cetrarin, and is of a green colour of greater or less intensity. It is to be collected on a strainer, and when it ceases to drop, it is to be pressed. Cetrarin is to be purified by separating it into small portions, and washing it while moist with alcohol or with aether, which deprive it of its colouring matter ; it is afterwards to be treated with twice its weight of boiling alcohol, which dissolves it, and allows it to preci- pitate on cooling. A further quantity may be obtained by evapo- rating the alcoholic solution. Cetrarin is sometimes a white powder resembling magnesia, and at other times it is in small globules united in the form of arboriza- tions, which exhibit no appearance of crystallization, even when ex- amined by the microscope. When pressed it has a silky lustre ; it is light, unalterable in the air, inodorous, with a decidedly bitter taste ; it is not entirely fusible ; it begins to become brown at 257° Fahr. At a higher temperature it yields a reddish-yellow acid oil, which becomes solid at 320" Fahr. It then blackens and leaves a great quantity of light charcoal, which burns readily in the air. It is soluble in boiling absolute alcohol, 100 parts of which take up 1-70; at 60° it dissolves only 0-28. The use of cetrarin in medicine is but recent, and it is impossible to say how far it may be employed ; it has, however, been exhibited as a febrifuge. The formula being, Cetrarin 2 grains. Gum arable .... 2 grains. Sugar 12 grains, Intelligence and Miscellaneous Articles. 297 for a dose, and it is recommended that it should be repeated every hour. — Journal de Chimie Medicate, November 1837. ACTION OF CHLORINE ON OTHERS. M. Malaguti finds that dry chlorine, while acting in the dark upon oxacid aethers, always attacks, and in a uniform manner, the sul- phuric aether which is the base of them. If the acid of the compound aether be represented by X, the formula, after the action of the chlo- rine, will always be X, C" H^ CI* O, that is, 4 atoms of hydrogen replaced by 4 atoms of chlorine. The action of potash on the compound chloridized aethers is also constant and uniform : the residts are always chloride of potassium, acetate of potash, and an organic salt with a base of potash, the acid of which is that which existed in the compound chloridized aether. Although the action of the chlorine is constant and uniform, the phaenomena which accompany it are not always the same. Thus the camphoric and oenanthic ethers, during the action of chlorine, give out only hydrochloric acid. The acetic and formic aethers, during the same action, disengage hydrochloric acid, and acetic or formic and hydrochloric aether. It sometimes happens that the acid of the com- pound aether is attacked by the chlorine, and presents, in its turn, the phaenomena of substitutions ; but the action of chlorine upon the sulphuric aether, which serves it as a base, is not modified, and re- mains independent. Sulphuric aether, subjected to the action of chlorine under the same circumstances as the compound oxacid aethers, among the numerous products which may be foreseen, yields a liquid, the elementary composition of which is C^ H<^ C^ O. This liquid is changed by the action of potash into chloride of potassium and acetate of potash. The aethers which M. Malaguti subjected to the action of chlo- rine are the camphoric, oenanthic, acetic, formic and benzoic. Some other compound aethers, as the mucic and pyrotartaric, appeared to him not to be attacked ; but he is going to resume these experiments, and to extend them to other aethers. At present, the agreement whicli the fore-mentioned facts prove to exist between the action of chlorine and the compound oxacid aethers, and the action of the same agent upon sulphuric aether, induce him to think that it is very pro- bable, when any other compound oxacid aether may be acted upon by chlorine, four volumes of hydrogen will be replaced by four volumes of chlorine in the base, allowing for modifications which the acid may undergo. — Journal de Chimie Medicate, November 1837. CAMPHORIC ACID. According to M. Malaguti, the formula for camphoric acid is thus written : Anhydrous acid C^" H'* O^ Hydrated acid C'^<> H'* O^, H^ O, Camphorate of silver, &c C-o H^^ O^, AgO. The acid, yielded by the action of nitric acid upon camphor, is 298 Intelligence and Miscellaneous Articles, -b the hydrated acid ; when it is sublimed, as first shown by M. Gui- bourt, it becomes anhydrous. M. Malaguti obtained the anhydrous acid in a different manner ; by decomposing camphovinic acid by distillation, he converted it into anhydrous camphoric acid and cam- phoric aether. He has also verified the composition of camphoric acid by analysing camphovinic acid, camphoric aether, camphorate of ammonia, silver, &c. He has observed that hydrous and anhy- drous camphoric acid produce salts sensibly different from each other, although dissolved in water, in the same manner as phosphoric and pyrophosphoric acid. He has also observed that camphoric acid in solution does not form a neutral ammoniacal salt ; that, in order to obtain this salt, it is requisite to expose the crystallized hydrated acid to ammoniacal gas until absorption ceases, in the same manner as performed by M. Robiquet with gallic acid. M. Laurent has also obtained results perfectly similar to those of Malaguti, respecting the composition of camphoric acid ; but they were not published so soon. — Journal de Chimie Medicale, November 1837. ON THE COLOURS OF METALS. BY MONS. R. BOTTIGER. It has long been known, that when very fine copper filings are put into a vial, and they are covered with a saturated solution of hydro- chlorate of ammonia, in 24 hours a colourless solution is obtained, provided only one-third of the vial contains air, and that it is well stopped and frequently shaken ; this solution, when exposed to the air, instantly becomes of a fine sky-blue colour, and is again ren- dered colourless by being again strongly shaken in the vial with the copper filings. This liquid is a solution of ammoniacal chloride of copper ; and if a slip of polished platina be put into it, no change is perceptible ; feut if, at the same time, it be touched with a piece of zinc, its sur- face, whatever may be its extent, becomes then completely covered with a very thin stratum of copper, and this disappears quickly, as soon as the platina is separated from the zinc. This fact is readily explained when it is remembered that the liquor contains a consider- able quantity of free ammonia. If also, instead of exposing the coated platina to the action of the ammoniacal liquid, it be immersed in a vessel of water, as soon as the coating of copper appears, it re- mains fixed on the platina, notwithstanding it may be agitated in the water. If, instead of removing the platina from the contact of the zinc as soon as the copper appears, this action is suffered to continue for a longer time, for example, during one or two minutes, bubbles of gas are given out, and copper is deposited in spite of its electro-positive state, the colour of which is no longer red, but, on the contrary, ap- pears black. At the same time, the red colour of the shp of platina, derived from the deposit of copper, which was at first fixed upon it, disappears, and in its place there arise various shades of all colours possessing remarkable beauty. Some are yellow, others green, others Intelligence and Miscellaneous Articles, 299 again red or brown, but the greatest number are black. When it is desired to fix these colours on the metal employed, it is sufficient to withdraw it from the liquid as soon as the last colours begin to pre- dominate, and to allow them to dry spontaneously in the air. By employing this simple and easy process, M. Bottiger succeeded in fixing the most incompatible tints on the same metallic surface, the aspect of which was, nevertheless, as soft as possible. — L Institute September 1837. ON THE ACTION OF PROTOXIDE OF IRON ON PROTOXIDE OF COPPER. M. Levol remarks that it is well known that the persalts of iron are reduced to protosalts by the protochloride of copper ; whilst the protosulphate of iron produces no such effiect with the salts of cop- per, aj; least with the sulphate ; this fact being known, superior affi- nity would, from analogy, be assigned to dioxide of copper over protoxide of iron ; but the facts which M. Levol states prove that this is not the case under all circumstances. If a mixture of sulphate of copper and protosulphate of iron be dissolved in water, no chemical action, as is well known, takes place, and the two oxides will remain mixed in solution, that is, under the most favourable circumstances for reaction without any occur- ring ; if, however, the oxides be precipitated by an alkali, the case is no longer the same, and experiment shows that peroxide of iron and dioxide of copper are obtained, instead of the oxides which ex- isted in the two salts ; the iron, therefore, is peroxidized at the ex- pense of the oxide of copper. The affinity of the two protoxides for sulphuric acid, the impossi- bility of forming a sulphate of dioxide of copper, and even of the existence of dioxide of copper in the presence of sulphuric acid, are causes which unquestionably oppose the reaction of the oxides in the two sulphates ; it appears, therefore, that half an equivalent of oxygen, separated from the protoxide of copper, leaves it in the state of dioxide ; and this, added to the equivalent of oxygen in the prot- oxide of iron, converts that into sesqui- or peroxide. That this is the case, is also shown by dissolving an equivalent of each sulphate in water, and adding ammonia to the mixed solutions. When kept from the contact of air, a colourless solution of ammoniuret of diox- ide of copper will be formed, and peroxide of iron precipitated, con- taining scarcely a trace of copper. If an equivalent and a half of sulphate of copper and one equi- valent of sulphate of iron be similarly treated, peroxide of iron will also be precipitated ; but blue ammoniuret of protoxide of copper will also be formed ; when, on the contrary, the proportions were reversed, a colourless solution was obtained which contained prot- oxide, both of iron and copper ; and by exposure to the air it con- sequently became of a blue colour, and precipitated peroxide of iron. Potash produces the same precipitation of dioxide of copper and peroxide of iron. 800 Intelligence and Miscellaneotis Articles, From the foregoing experiments M. Levol concludes : First. That when ammonia is employed as a reagent, it may hap- pen that the presence of copper, even in large quantity, may escape detection, if the solution also contains protoxide of iron, especially if it be supposed that this oxide is either partially or totally in the state of peroxide. It is not even requisite for this that the operation should be conducted in a close vessel, if the iron preponderates ; because, when once solidified, the pellicle of oxide formed at the upper part of the solution preserves the rest from further oxidize- ment. Thus, in an analysis, or to discover by ammonia copper mixed with iron, it is requisite first to peroxidize the iron entirely. Second. As no suboxide of nickel exists, it cannot occasion the same reaction ; and therefore a new method of distinguishing it from copper results, when in the state of a double ammoniacal salt. This is effected by pouring an excess of solution of a protosalt of iron into the ammoniacal solution, which immediately decolorates it if copper, and not nickel, be held in solution, operating out of the contact of the air. — Annates de Chimie et de Physique, July 1837. ON THE GASES CONTAINED IN THE BLOOD, AND ON RESPIRA- TION. BY M. G. MAGNUS. M. Magnus remarks that it remains a question whether carbonic acid is formed in the lungs by the oxidizement of a part of the car- bon in the blood by the action of the air, or whether venous blood, when it reaches the organs of respiration, contains carbonic acid ready formed, which is merely separated from it. M. Magnus passed hydrogen gas through a solution of potash to deprive the gas of any carbonic acid which it might contain, and when it gave no precipitate with lime wate he passed it into the blood of a healthy man ; the gas afterwards made to go through lime water o-ave a plentiful precipitate of carbonate of lime. Azotic gas simi- larly employed produced a like effect; and M. Magnus concludes, from these experiments, that carbonic acid exists ready formed in the blood, and consequently that it is not formed in the lungs. Car- bonic acid was also separated from blood by means of the air-pump. By using Liebig's apparatus M. Magnus found that blood contained about one- fifth of its volume of carbonic acid gas, and when it had been kept 24 hours, without emitting any bad smell, the quantity was larger. The results were confirmed by employing atmospheric air instead of hydrogen gas. M. Magnus then ascertained the nature and proportions of all the gaseous contents of the blood. He found that 100 volumes of the arterial blood of a horse yielded Carbonic acid gas 4*32 vols. Oxygen r52 „ Azote 2- ,, Total 7-84 vols. The venous blood of the same horse, drawn 4 days afterwards, gave Intelligence and Miscellaneous Articles, 301 Carbonic acid gas 4*29 vols. Oxygen , 1*12 „ Azote '54 „ Total 5-95 vols. ITie arterial blood of the calf contains more, and the venous blood less oxygen, than that of the horse. M. Magnus observes that these experiments, and others which we have not copied, appear to show that the gases contained in the blood of the animals, amount to about one-eighth or one-tenth of the quantity employed. He admits however that the experiments are not absolutely precise, because they were not all continued the same length of time, &c. But he observes, that as the proportions between the oxygen and carbonic acid are invariably the same, these results may be regarded as satisfactory. With regard to the theory of respiration all experimentalists agree as to the reciprocal proportions between the carbonic acid expired and of the oxygen absorbed ; while however some of them are of opinion that those quantities are always equal, as must happen if the oxygen gas were employed merely in the formation of carbonic acid in the lungs, there are chemists whose results show that more oxy- gen is inspired than carbonic acid expired. Messrs. Allen and Pepys observed that this was constantly the case when the same air was repeatedly respired. M. Magnus adds, that this fact, so inexplicable by other theories, is an immediate consequence of the hypothesis founded on the law, that a liquid holding a gas in solution parts with it when it comes in contact with another gas. Another circumstance noticed by Messrs. Allen and Pepys is as in- explicable as the preceding, namely, that by the respiration of oxy- gen, or by a mixture of oxygen and hydrogen, azotic gas is constantly expired, the volume of which is proportional to the bulk of the ani- mal ; this proves that it cannot at all be attributed to the air. It now remains to be shown that the carbonic acid extracted from the blood is in sufficient quantity to account for the whole of that which the lungs expire. The results obtained on this subject are discordant ; those of Messrs. Allen aud Pepys evidently exceed what they should be ; for Berzelius has shown that, if correct, it would require six pounds and a quarter of solid nourishment in 24 hours to produce the quantity of carbon consumed. Taking then the results obtained by Davy as a mean of those of Lavoisier, Allen and Pepys, although perhaps a little too high, we shall have 13 cubic inches as the quantity of carbonic acid gas ex- pired by a man. If it be further admitted, that at each pulsation of the heart an ounce of blood arrives at the lungs 75 pulsations in a minute would convey live pounds of blood in the same time. This is the minimum quantity which can be admitted ; for it is very pro- bable that five pounds of blood pass through these organs every mi- nute : these five pounds produce 13 cubic inches. It has been already mentioned that the blood contains at least one-fifth of its volume of carbonic acid; and as a pound is equal to 25 cubic inches, each pound of blood would contain at least 5 cubic inches of carbonic S02 Intelligence and Miscellaneous Articles. acid. It will be observed that no circumstance opposes the proposed theory, hence the experiments prove, that the quantity of carbonic acid contained in venous blood, is more than sufficient to furnish the quantity expired. — Journal de Chimie Medicale, November 1837. ON THE LOW TEMPERATURE OF JANUARY 1838, BY MR. F. WATKINS. To the Editors of the Philosophical Magazine and Journal. Gentlemen, As my own residence is so unfavourable for meteorological obser- vations, I have had for many years, in the Blackheath road, a series of instruments under the charge of a gentleman of high scientific acquirements, and devoted to the study of the various phaenomena which occur in the aerial regions. From his observations a diagram has been formed, showing the maximum and minimum thermometric curves for the month of January as compared with the mean. The beginning of the month was mild, both curves being above the mean temperature of Greenwich, deduced from twenty years' observations. Towards the 8th both curves descended far below the mean, and continued so till, on the 20th, just at sun- rise, the ther- mometer stood at 4^ below 0 or zero, or 40° below the mean of the period. This low degree of temperature lasted some hours, for at 9 a.m. it was —2°, at 10 a.m, -f 1J° at 11 a.m. +4^ and at noon only 4- 7°, after which it rose many degrees, and the wind veered from the east to south. On the 22nd both curves ascended above the mean, and on the 23rd descended as abruptly below, accompanied by a strong easterly gale, which continued until the end of the month. • Two things may be here remarked, as being unprecedented in the annals of meteorology in this country : 1st, the thermometer below zero for some hours ; and 2ndly, followed, almost immediately after, by a variation of nearly 50 degrees. It should be noticed however from general observation that thaws commonly succeed very unusual low degrees of temperature. My friend informs me, that before last month the lowest degree of temperature he has ever registered during thirty years, is +4°, and that only once, and it was very transient. The temperature of the month had been gradually preparing us for an extreme of cold, for on the 12th the minimum was 12°*2, on the 13th 90-6, and on the 15th 6o-5. From the 18th to the night of the 19th, on which day there was only a maximum of 21", the approach of an unusual degree of severity was indicated ; the radiator on the snow at 6 p.m. marked 9° : the evening proved cloudy with a variable temperature from 15° to 12°. The lowest mean tempera- ture for the month (for twenty years) falls about the 16th. Finally, the average degree of cold on our very severe night is 16°; therefore the thermometer on the night of the 19th departed 20° lower than this, a circumstance, happily for us, of rare occurrence in this climate. I remain, Gentlemen, yours, &c., 6, Charing Cross. Fkancis Watkins, Meteorological Observations for January 1 838. 303 Just published, No. I. New Series, Annals of Natural History, or Magazine of Zoology, Botany, and Geology. (Being a Continuation of the * Magazine of Zoology and Botany/ and of Sir W. J. Hooker's ' Companion to the Bo- tanical Magazine.') Conducted by Sir W. Jardine, Bart., P. J. Selby, Esq,, Dr. Johnston, Sir W. J. Hooker, Regius Professor of Botany, Glasgow, and Richard Taylor, F.L.S. METEOROLOGICAL OBSERVATIONS FOR JANUARY 1838. Chisunck. — Jan. I. Fine: slight rain: very fine. 2. Cloudy and fine. 3, 4. Very fine. 5, 6. Dense fog. 7. Bleak and-fiold. 8, 9. Frosty : slight snow. 10 — i;i. Frosty. 14. Snowing. 15 — 18. Continued severe frost. 19,20. Most intense frost. 21. Overcast: thawing. 22. Fine. 23. Hazy and cold. 24 — 27. Frosty : bleak and cold. 28 — 30. Fine. 31. Hazy and cold. On the night of the 19th and morning of the 20th, the frost was more intense than has been the case fOr at least the period since the commence- ment of the present century. The registering thermometer in the Arbo- retum of the Horticultural Society's garden was 4 degrees below zero of Fahrenheit's scale; and some thermometers in the neighbourhood, in more exposed situations, indicated 6 degrees below zero. The destruction of subjects of the vegetable kingdom has in consequence been unprecedented in this country, within the memory of any now alive. — R.T. Boston. — Jan. 1. Fine: beautiful morning. 2. Cloudy. 3. Cloudy: rain early a.m. 4, 5. Fine. 6. Foggy. 7. Cloudy. 8, 9. Snow 10, 11. Cloudy: snow a.m. and r.M. 12. Cloudy. 13, Snow. 14. Fine 15, 16. Cloudy. 17. Fine: snow early a.m. 18. Fine: large fall of snow early a.m. 19. Cloudy. 20. Cloudy: Ther. 12, 5 p.m. 21, 22. Cloudy. 23, 24. Stormy. 25—28. Cloudy. 29. Rain : snow early a.m. rain p.m. 30. Foggy: rain p.m. 31. Cloudy. Penzance. — Jan. 1. Fair and clear. 2. Very stormy, rain, fair at night. 3. Cloudy, showers. 4. Fair and clear. 5. Fair with clouds. 6, 7. Cloudy, a shower. 8. Cloudy. 9. Clear and fair. 10. Snow. ll.Sleet, fair at night. 1 2. Misty, fair and clear at night. 1 3. Stormy, sleet. 14. Cloudy, clear at night. 1 5. Rain, evening fair. 1 6. Sleet, fair at night. 1 7. Fair and clear, snow shower. 18. Fair and clear. 19. Cloudy, snow. 20. Cloudy and stormy. 21. Misty. 22. Fair and clear, evening a shower. 23. Fair with clouds, evening fair and clear. 24. Very stormy. 25. Cloudy, showers, stormy. 26. Cloudy, heavy showers at night. 27. Showers. 28. Fair with clouds, showers in the evening. 29. Fair and clear. 30. Cloudy. 31. Fair with clouds. The early part of the month was mild though stormy; the thermometer reaching as high as 49°. Cold commenced on the 8th, and continued to increase in severity till the morning of the 19th, when the thermometer stood at 23", the wind blowing from E.S.E. On the 20th the tempera- ture had risen to 45", the wind still continuing to come from the eastern quarter; the mercury in the instrument kept advancing till the29th,when it arrived at its maximum, 50° ; the wind suddenly veering to the W., but proceeding from that direction for only twenty-four hours, when it again moved round to the E., which produced a consequent depression of tem- perature. Though the barometer gradually fell in the space of ten days (from the 18th to the 28th) more than an inch, yet the rain in the gauge did not amount to an inch. The anemometer during this period marked E. to E.S.E. This month must be considered a remarkably fine one, though cold for this part of England. 11 «9^ to •ZU3J O lO ,-300 o : :^ : ' 6 .8 o ' 6 o CO 6 6 ' 6 o o o o •U0»80a -a «« w g g g' w w S » ^* ^ i^ ^ >^ ^ ^ g S I ^ I g S g I g H - « g g s - , S5 « « (^ H M CO (M O 00 t^ O CS 0'*COTl.'^iO^O. to •^•<*-^-^COCOCOCOO»rNOI«MCNO«CI»cOcocO'^COCO In •as oooc^'^QpcoocpprNqpt^Qpoo^rrc^•^c^^pQOC^^^Tfoo•^•<*lOoooooo ■rCco.^.^"" .Qp co-vooco'^cpcp"^r^9 900900 ipop-^r^t^OQp t>-Qp op (N >o»b"«rol^>ooo■^lpTtcoco«_oo<«;<09co-^r^ ICNCp a^a^o^o^o^o^o o o o^o^o o o^3^o^6^6^6^c^6lC^6^6^6^6^6^o^6^G^6^ (MC^C<CN(N(NCI(NCl n t^00C0(MC0CSVOO-00tO'-'lr^i0C00l-rti0M0t0Ot^C0 o^«toa^o^o^coc^-^o^oo^o^ooa^(^^o^ o -^r^c coo^•r}'0^oo dCTitO-rf-NlOCriQOfN 00 OM^r^r^tr^TTcoco 0^ On On on On On on on on rNCOOI(NCN(NrNC« (N (N f«ClVOOCOI>- (Nco'^toot^oooNO — otco-^trsvo r--oo <^c> ^ r:^ r^'rr\o^ x>-co 0'\0 "^ — -.-H-. — — — -4 — — CiCNOIC«O«OI 6 11*5 to max. of 4th 2nd to 4th 3rd } } } 7-5 3-5 to 4th From minimum 1 of 1st order > 6 8'5 to min. of 4th 2nd to 4th 3rd 4-75 to 4th In all such experiments the most troublesome part consists in having to wait in each instance until the apparatus has cooled down to the same temperature, before commencing. This and numerous other precautions are not here dwelt upon, as they will soon suggest themselves to those who may be induced to enter upon such experiments. XLIX. On the Nature and Properties of Teriodide of Chro- mium. By Mr. Herbert Giraud, F.B.S.E,, Mem. Med. Soc, Edin. To the Editors of the Philosophical Magazine and Journal, Gentlemen, A LT HOUGH the remarkable and beautiful combinations '^ of chromium with chlorine and fluorine are well known to every chemist, yet I am not aware that any iodide of chromium has hitherto been formed; therefore a short ac- count of one which I have recently produced may not be un- interesting. When we consider the relative electro-chemical condition of iodine compared with that of chlorine or fluorine, we are led to conclude that if any combination can be effected be- tween chromium and iodine, such a combination would be held together by weaker affinities than those which are exerted in the analogous compounds of chromium with chlorine or fluorine ; accordingly we find that the compound we are about to describe is subject to decomposition from slight causes. Th^ Phil. Mag. S.3. Vol. 12. No. 75. April 1838. 2 H 322 Mr. H. Giraud on Teiiodide of Chromium, method adopted for the production of this compound was similar in character to that which is generally made use of for the formation of the terchloride or terfluoride of chro- mium, 33*5 grains of chromate of potassa were intimately mixed with 165*45 grains of dried iodide of potassium (the quan- tities being in the proportion of 3 equivalents of iodide of potassium to 1 of chromate of potassa); these materials were then introduced into a tubulated retort, to which a receiver was adapted; about 70 grains of fuming sulphuric acid were then poured upon the materials in the retort ; this instantly gave rise to intense chemical action, accompanied by the evolution of much caloric and the production of heavy gar- net-coloured fumes, which constitute the iodide of chro- mium in a state of vapour : the elevated temperature already induced was sustained by means of a spirit-lamp, and the fumes continuing to come over were condensed in the neck of the retort and in the receiver. A small proportion of free iodine and also of sulphuric acid were carried into the re- ceiver : the products remaining in the retort were sulphate of potassa and green sulphate of the oxide of chromium. In every attempt which I have made to procure this sub- stance, with varied proportions of the materials, I have never been able to obtain it quite independent of a small proportion of free iodine and sulphuric acid ; it therefore appears, that it is not essential that the materials should be employed in the exact proportion of their equivalents. The essential changes which occur in the formation of this substance are expressed by the following formula : 3 KI, (KG + CrO^) and 4 SO^ = 4 (KO + SO^) and Cr F. The teriodide of chromium, like the other compounds of that metal, is remarkable for the brilliancy of its colour, which is of a deep garnet hue; it is a fluid of an oily consist- ence, heavier than water, converted into a dense vapour, possessing the same colour as the fluid, at a temperature of about 300° Fahr. ; when exposed to the air it attracts moi- sture, and thence gives rise to watery fumes; by mixture with water it is resolved into chromic and hydriodic acids ; it de- stroys organic substances, gives a black colour to paper and wood, stains the skin of a deep and permanent brownish-red colour, and destroys the cuticle; it is also destructive of animal and vegetable life. If the teriodide could be obtained free from adhering sul- phuric acid, its analysis would be easily effected and its com- position determined by means of a soluble salt of lead, a so- Prof. De Morgan on certain Relations in a solid Figure. 323 lution of which being added to the teriodide of chromium gives rise to iodide of lead and chromate of the oxide of lead, which are readily separable, the iodide being soluble in boiling water, while the chromate is insoluble; but sulphate of lead is formed, which^is also insoluble. It unfortunately happens that the degree of heat required for the formation of the ter- iodide always causes a small quantity of sulphuric acid to be carried over with it. The proof, however, which we have that this compound is indeed a teriodide of chromium, is afforded by the fact of its being resolved into the chromic and hydriodic acids by the action of water. I am, Gentlemen, yours, &c., Edinburgh, Feb. 5, 1838. HERBERT GiRAUD. L. On the Belation between the Number' ofFaces, Edges, and Corners in a Solid Polyhedron. By Augustus De Morgan, Professor of Mathematics in U?iiversity College.* T^HE remarkable relation which exists between the number -*■ of edges, faces, and corners (or solid angles) in a solid figure, namely, that the number of faces and corners together always exceeds the number of edges by two, is usually de- monstrated by reference to the celebrated expression for the area of a spherical triangle. The theorem was given by Euler, in the Petersburg Acts for ] 758 ; but not having access to that work, I cannot tell whether he employed the method just alluded to, or not. However, since Legendre has derived the theorem by means of the spherical triangle, as well as every other elementary writer with whom I am acquainted ; and since an equally simple relation which exists among the edges, corners, and faces of a portion of a solid figure has been little if at all noticed, I conjecture that the following demon- stration is new. At any rate, it is more simple, and derived from more elementary principles, than the one commonly given, and is therefore worthy of notice. Let there be a number of polygons, so placed that each has a common edge with one or more of the others. Let every angular point be called a corner (whatever may be the number of lines which meet there) ; every line joining two corners, an edge ; every unsubdivided portion of space, a face. Then the number of faces and corners together will always exceed the number of edges by one. For this is evidently true of a single polygon, while for every polygon which is added, the number ot new edges is one more than the number * Communicated by the Author. 2H2 324« Prof. Johnston on the received of new corners. But the additional polygon is one new face ; therefore the addition of each new polygon increases the faces and corners together as much as the edges ; consequently the initial relation, namely, No. of faces + No. of corners = No. of edges + 1 remains undisturbed. The preceding is equally true if the faces be not all in one plane, and consequently it is true of any portion of a solid figure which is not the whole. It is true then of a solid figure from which one face is omitted, the edges of that face answer- ing to the exterior contour in the preceding theorem. Con- sequently, including the face just omitted, and thus com- pleting the solid, we have No. of faces + No. of corners = No. of edges + 2. LI. On the received Equivalents of Potash, Soda, and Silver, By James F. W.Johnston, AM., F.RS. L.Si'E., Professor of Chemistry, University of Durham.* TN the progress of the sciences of observation it is interesting -*- to remark how the establishment of every new principle is opposed by certain apparent exceptions or anomalies, yet how these anomalies all ultimately disappear, and how the removal of each is necessarily preceded either by some cor- rection of received opinions, or by fresh additions to our ac- tual knowledge. The researches of Dulong and Petit into the specific heats of the metals rendered it extremely probable that the atoms or equivalents of these elementary bodies had the same spe- cific heat. This relation was found to hold with remarkable exactness in the case of a considerable number of metals ; but to bring silver, gold, and mercury into conformity with the law, it was found necessary to reduce by one half the atomic weights of these metals as generally received among chemists. The result of these beautiful researches therefore, though they pointed to and rendered probable the existence of a very simple relation among the specific heats of the metals as a law of nature, yet being opposed by so many apparent exceptions, have not been generally received with that confidence to which they may ultimately prove to be entitled. Chemists have been unwilling to alter the received atomic weights of so many metals for the sole purpose of bringing them into conformity with a relation still considered hypothetical. • Communicated by the Author. Equivalents of Potash^ Soda, and Silver, 325 In the progress of discovery, however, other facts were ob- served, which though at first appearing to oppose the law in question, have yet been preparing the way for the removal of the exceptions which opposed its general reception. Among the admirable observations of Mitscherlich on the isomorphism of analogous compounds was the identity of form of the sul- phate and seleniate of silver with the anhydrous sulphate and seleniate of soda from which the isomorphism of silver and sodium was deduced; and as the same quantity of sulphuric acid existed in these compounds in union with the received atomic weights of the soda and oxide of silver, the opinion was strengthened that these weights were correct. Professor Gustav Rose more recently established the identity of form of silver and gold; and though his analyses of native gold from different localities did not confirm those of Boussingault, that the two precious metals in native crystals replaced each other in atomic proportions, yet their isomorphism connected those metals by another link, and tended to strengthen the received opinion in regard to the equivalent weights of both. Thus far the progress of discovery was opposed to the results of Dulong and Petit. When by the sagacity and elaborate researches of Berze- lius the doctrine of the sulphur salts was established to the satisfaction, at least, of the German chemists, who understood it best. Professor Henry Rose entered upon the study of the various compound metallic sulphurets which occur so abun- dantly in the mineral kingdom. The results of this inquiry, while they confirmed the beautiful doctrine of Berzelius, threw an unexpected light on the nature of these sulphurets, and gave a simplicity to their constitution wholly unthought of; and while they made known the existence of many isomor- phous relations which were to be anticipated from those al- ready observed among the analogous oxygeri compounds, they brought to light others also which could not even be suspected to exist. To one of these only, having reference to the atomic weight of silver, it is necessary at present to ad- vert. The sulphuret, oxide, and chloride of silver are composed respectively of Silver. Sulphur. Oxygen. Chlorine. 1 Atom each 13*5 2-0116 1-000 4-4265 The analogous compounds of copper consist of Copper. Sulphur. Oxygen. Chlorine. 1 Atom each 7*9 2-0116 1-000 4-4265 and the disulphuret of 1 5-8 + 2-0116. 326 Prof. Johnston on the received Now in certain compound metallic siilphurets the sulphuret of silver is replaced by the disulphuret of copper, and not by the native sulphuret consisting of 7*9 copper + 2*0116 sul- phur. Thus in Fahlerz (gray copper), for which the general for- mula is R4 ft + 2 Cu4 R^or R^ ]S' + 2 Ag^ R, the first representing the copper and the second the silver Fahlerz, we have identity of crystalline form and identity of chemical formula, if it be admitted that the compound Ag is capable of replacing the disulphuret Cu, and that these two minerals are varieties of the same species. It is so far fa- vourable to this view, that though native crystals of disulphuret of copper (Cu) occur in rhomboids of 71° 30' nearly, yet that by fusion of the artificial as was first observed by Mitscherlich, or of the native sulphuret as observed by G. Rose, this com- pound can be obtained in octohedrons like native sulphuret of silver (Ag). The occurrence of two substances in any form belonging to the regular system does not, it is true, prove them to be isomorphous, yet in the present case, the several circumstances connected with the forms and apparent mutual replacement of these two compounds are such as to have in- duced some distinguished chemists to consider their isomor- phism as certain. It has however been placed almost beyond doubt by the discovery at Riidelstadt of a sulphuret of cop- per and silver in the rhomboidal form of the sulphuret of copper (Rose, Pogg. xxviii. p. 427), and consisting according to Sander (Ibid. xl. p. 313) of equal atoms of either sul- phuret (Cu + Ag).* But the isomorphism of two compounds generally implies an analogy in their atomic constitution, — that they are both sulphurets of the same order. If the compound of copper be » a disulphuret Cu, that of silver is most probably a disul- phuret Ag, and if so the atomic weight of silver must be re- diuced one half, or to 6*75. We have here therefore an argu- ment in favour of the old result of Dulong and Petit. * In stating that it is placed almost beyond doubt, I take for granted that the crystals f'rona Riidelstadt, of which the analysis is published by Sander in Poggendorff's Annalen for 1837, part ii. p. 313, are different from the imperfect crystals measured by G. Rose, and of which an account is given in his crystallography published in 1833, p. 158. Equivalents of Potash^ Soda, and Silver* 327 The introduction of this change, however, would render necessary a like change in the received atomic weight of sodium, with the oxide of which in anhydrous sulphate of soda (Thenardite) that of silver in sulphate of silver is isomorphous. Soda, common salt, and sulphuret of sodium must be represented by Na, NaCl, Na. Nor can the change stop here. Several years have elapsed since Mitscherlich announced the very interesting fact, that the nitrates of potash and soda were isomorphous respectively with arragonite and calc spar, and that they presented the same cleavages (Pogg.Ann. xviii. p. 173.) ; to which Mar after- wards added that the rhomboids of nitrate of soda possessed the doubly refracting structure in a higher degree even than calc spar [Jahrbuch dei- Chim.und Phys., xix. p. 165). From these observations it was natural to infer that some relation existed between the two alkaline nitrates analogous to the re- lation between the two forms of carbonate of lime ; that like carbonate of lime the nitrates of potash and soda might each be capable of assuming two forms isomorphous each with each, though in ordinary circumstances of temperature, &c. the class of form preferred by each did not correspond ; the nitrate of potash generally aiFecting the right rhombic prism, the nitrate of soda the rhomboidal form. The probability of such a re- lation was strengthened by a comparison of the analyses of chabasie from different localities and by different chemists, from which there appeared strong reason for believing that potash and soda were capable of replacing each other in equi- valent proportions. The alums however presented an anomaly. Nothing posi- tive in regard to isomorphism could be inferred from potash and soda occurring indifferently, and in equal atomic propor- tions, in similarly constituted crystals of the regular octohe . dral and cubical forms ; they might occur indifferently in such crystals without being isomorphous : but supposing them really to be isomorphous, there appeared an inconsistency in the alleged existence of 26 equivalents of water in soda alum, while potash alum contained only 24 atoms. This objection has been lately removed by Professor Graham, (London and Edinb. Phil. Mag., vol. ix. p. 26,) who has shown that soda alum when perfectly dry contains only 24 atoms of water, and that the potash and soda alums therefore have the same con- stitution*. But all doubt has at length been removed from the relation between the forms of potash and soda by a beautiful observa- [• The identity of constitution of the potash and soda alums had been previously shown we believe by Dr. T. Thomson. — ^Edit.] 328 On the received Equivalents of Potash, Soda, and Silver. tion of Frankenheim (Pogg. xl. p. 44?7). He has found that when a saturated solution of pure nitrate of potash is left in small quantity to spontaneous evaporation two sets of crystals are formed ; one in prisms, the other in rhomboids ; the former the common arragonitic form generally assumed by nitrate of potash, the latter that of calc spar, commonly assumed by nitrate of soda. The rhomboidal crystals are microscopic and pass into the prismatic form by friction, by pressure, or by contact with a prismatic crystal, and hence when the salt is crystallized in large masses they entirely disappear*. It may therefore be considered as demonstrated that the nitrates of potash and soda are at once isomorphous and dimorphous, or isodimorphous ; and since the potash and soda replace each other in certain mineral compounds, the alkalies also, perhaps the metallic radicals themselves, may be considered isodimor- phous. Whatever change then we adopt in regard to the atomic weight of silver the same must be adopted for potash and soda. If we halve the atom of the former, potash and soda must be represented as dioxides. Kg O and Nag O : and if we consider the united observations of Boussingault on the com- position of the native alloys of gold and silver from South America, and of G. Rose on the crystalline forms of the native metals in a state of comparative purity to be sufficient evi- dence of the isomorphism and replacing powers of gold and silver, we must also halve the received equivalent of the former metal ; or for the four metals in question we must adopt the equivalents Gold -—— Totassmm ... -- — 2 2 oM 13*5 ^ ,. 2-912^ Silver -—— - Soamm — - — f of which the former two are the multiples indicated by the researches of Dulong and Petit. I leave it to British chemists to judge how far the reasons here stated are sufficient to authorize the introduction of the proposed change. In compiling the second part of my tables of chemical constants it has been necessary to subject many points of this nature to a critical examination ; and if in these tables I should find it necessary to adopt the smaller multiples for the equivalents of the metals above mentioned I am an- xious that the cultivators of chemical science into whose hands they fall may have an opportunity of estimating the united [* See Mr. Talbot's Observations, p. 147 of the present volume. — Edit.] t For easy reference I have copied these weights from Turner's Che- mistry. Oji the Path of the " Boomarang:' 329 force of the several reasons by which I may have been influ- enced in doing so*. Durham, September 1837. Note, — It may be in the recollection of many of the readers of this Journal, that Dr. Clarke of Aberdeen, in a letter to Professor Mitscherlich published in the Records of Science, endeavoured to show that the atoms of one or more of the alkaline metals should be doubled; in a subsequent paper I propose to consider the principle on which his reasoning is founded. LIl. On the Path of the projectile Weapon of the Native Australians called the " Boomaran^^ or " Kylee." By a CoRRESPON DENT, t To the Editors of the Philosophical Magazine aiid Journal, Gentlemen, A SHORT time since my attention was directed to the " Boomaran^^ or " Kylee^^ known for a considerable time to the scientific world, and at present become a very general source of exercise and amusement. You must be aware that when thrown in a certain direction, it will return to, and sometimes far beyond, the spot from which it was projected. Curiosity induced me to devote some attention to the subject ; and unable to see any insufficiency in the following simple causes, by which I have endeavoured to account for this curious property, 1 am surprised that none of your learned correspondents has favoured the public with any explanation of it. Should the following observations appear worthy of the attention of your readers, I am sure you will not refuse them an early insertion in your excellent Journal. I. To explain the principles on which the kylee ascends, and afterwards returns to the place from which it was pro- jected, it will be necessary to consider the various forces which act on it, from the time it is projected until its return to the earth. These forces appear to me to be five: first, that of projection ; secondly, that of gravity ; thirdly, the re- sistance of the air to its plane or level side ; fourthly, that re- sistence to its curved side ; and fifthly, to its edge. The last three forces, though distinct in their effects, are but one in their nature or cause. In enumerating these forces, I have supposed your readers to be perfectly acquainted with the form or shape of the body. Let us now examine the effect [* How will this subject be affected by the application of the mode of determining true atomic weights pointed out by Mr. Faraday, in his {Seventh Series, par. 851 ; or L. and E. Phil. Majr., vol. v. p. 430? Edit.] t A notice of a paper on the Boomarang will be found in our report of the Royal Irish Academy's Proceedings in a future page. 330 On the Path of the projectile Weapon produced by each of these forces separately, and we shall be better able to estimate with precision their conjoint effects. 2. Before the body is projected, it must be observed, that there are a variety of angles with the horizon, at each of which it might be thrown ; but, for the present, we shall confine our- selves to two, I mean the angles of projection and inclination. By the former, I understand the angle which the plane of the horizon makes with the direction in which the body is pro- jected ; and by the latter, I mean the angle which the plane side of the body makes with the horizon. These two angles should be accurately attended to, as they are quite distinct. 3. When the body is projected in any direction, and at any angle of inclination, say 40° or 50°, the effect of the first force, viz. projection, will be to impel it forward; that of the se- cond, viz. gravitation, to cause it to descend : but the effect of the third force, I mean that which acts on the plane side, will be, first, to counteract and nullify the fourth force, which acts on its curved side, and by this means, becoming itself 5wpmor for a time to gravitation, its ultimate effect will be to bear the body upwards in a curvilinear direction. Finally, it will co- operate with the fifth force, (the effect of which, inasmuch as it acts on the edge of the body, is scarcely estimable,) in causing the body to gyrate around its axis. This axis is ob- viously an imaginary line at right angles to the plane surface of the body, and passing through the point on which the body would balance itself, in the position in which its plane surface would be parallel to the horizon ; i. e. if the body be supposed for a moment to rest on the paper on its level side, and if the paper be parallel to the plane of the horizon, the position of the axis is a perpendicular to the horizon passing through the centre'of gravity of the body while in this position. 4. It is easy to perceive that the body will ascend in a curvilinear direction, if the five forces above mentioned are ca- pable of producing the different effects which I have attri- buted to them. That the projectile force will impel the body forward, and that of gravity downward, cannot be questioned. Not so the effects ascribed to the other three. I shall there- fore proceed to explain whatever may appear not sufficiently satisfactory in my assertions regarding them. The third force above mentioned is the resistance of the air to the plane or level side of the body. This force, if not twice as great, is at least much greater than the force acting against the curved side. This truth will appear evident, if we consider atten- tively the following facts. 5. If a globe and cylinder of the same diameter move in an uncompressed fluid in the same direction, viz. that of the axis of the cylinder, the base of the cylinder suffers twice as much of the Native Australians called the " BoomarangJ* 331 resistance as the globe. See Sir Isaac Newton's Principia, lib. ii. prop. 34 ; also Vince's Hydrostatics, prop. 29. From page 1 1 of App. to last-mentioned work, it appears that ex- periments prove the resistance aforesaid to be even in a greater ratio than theory teaches, viz. in the ratio of 2*23 : 1 nearly 2^: 1, i. e. 9:4. Also, from the same page, we learn that the resistance to the plane side of a semiglobe is greater even than the resistance to the base of its circumscribed cy- linder. Hence we may infer that the resistance to a plane surface moving in a fluid is considerably increased by the cur- vature of the back part of the body. 6. From a careful attention to these facts, we can have no difficulty in admitting that the plane surface of the kylee suf- fers a resistance, if not twice as great, at least much greater than the curved side ; and consequently, since the forces acting on its two sides are in opposite directions, whatever may be the extent of the resistance to the curved side, it is altogether counteracted and nullified by the superior resistance to the level side. And not only this, but we may also see, as I will show immediately, that the excess of the more powerful over the weaker force remains a free agent, unexhausted, and there- fore capable of bearing the body upwards for a time in op- position to gravitation. 7. I stated above (3.) that the force which acts on the plane side is for a time superior to gravity ; and before I prove the correctness of this assertion, I may remind you, in connection with this point, of the principles by which is explained the cause that makes a boy's kite hover for hours suspended in the air, notwithstanding its greater specific gravity. You are aware that the kite, by constant tension of a cord attached to it, is made to act on the air, the particles of which, since action and reaction are equal and in opposite directions, react on the kite in a contrary direction, and thus support it against gravi- tation as long as the cord is held tight. 'T is the same prin- ciple which enables a bird to support itself on its wings; and it is worthy of remark, that there is a very striking resem- blance in the shape of a bird's wing to the figure of the body in question. 8. I shall now proceed to show that the force acting on the plane surflxce is for a time Superior to gravity, or, which is the same thing, that it acts upwards. When the body is projected in any direction, its plane side making with the horizon an angle of 40° or 50^^, and the projector holding the plane side off*, and the curved side towards himself, the plane side, by impinging on the first volume of air, generates, as we have seen (5.), a certain resistance to itself, which is in some ratio to the velocity with which it moves (generally admitted to be 332 On the Path of the projectile Weapon as the square). And since both the plane and curved sur- faces of the body act simuhaneously on the air, and are, there- fore, simultaneously reacted on by it ; and since this reaction is so much greater (5.) against the plane than the curved side, it follows manifestly that there remains an excess of force act- ing on the plane side, which will cause it to deviate from the direction of its first motion. And in what direction will it be turned ? Evidently in the direction imparted to it by the force acting on it. To ascertain this direction, we must bear in mind, that the body was projected with its plane surface ma- king with the horizon an angle of 40° or 50° ; and if we esti- mate, as we may, (see Wood's Mechanics, Comp. and Res. of Forces,) the total efficient resistance in a direction perpendi- cular to its plane surface, it is manifest that the direction of the force in question will be a line making with the horizon an angle of 40° or 50°, or in other words its direction in the first instant after projection will be that angle with the plane of the horizon which is the complement of the angle of in- clination. Therefore, as this force acts at an angle of 40° or 50° with the horizon, it is an upward force. The same pro- cess will be gone through in the second instant, and so on until the velocity of projection is spent ; and then the up- ward impulse, depending for its existence on the continuance of the projectile force, will also cease. Hence this force is, as I said, superior for a time to gravitation, 9. I said that we may estimate the total efficient force which acts on the plane side in a direction perpendicular to that side (8.). Should this be objected to, we may ascertain its real direction. It cannot be forgotten that the pressure on the plane surface is much greater than on the curved ; and the particles of air are acting on it in every direction, but cer- tainly not with equal force in every direction. For the par- ticles that impinge on the plane surface with the greatest effect, are those that act on it at an angle of something about 54° with the direction of its motion. My reason for this assertion is, because it is proved (Vince's Fluxions, Max. and Min. p. 24, edition 5.) that the greatest effect produced by the wind on the sails of a windmill is when the wind acts on them at an angle of 54° 44'. Since it is the same thing whether the body moves against the fluid or the fluid against the body (see Principles of Hydrostatics), it follows, that when the body is in motion, those particles which impinge on it at the aforesaid angle with the direction of its motion, resist it more powerfully than any other particles acting on the same side, and conse- quently have the same tendency to make it deviate from the line of projection as the causes already explained. 10. I have now, as briefly as I could consistently with per- oj the Native Australians called the ^^Boomarang" 333 spicuity, endeavoured to develop the causes by which the body is made to ascend ; and before I explain those which effect its return, I shall, with the aid of the annexed diagram, enumerate them, and their effects, for the satisfaction of some of your readers. The figure is a parallelipipedon. Let the body be projected from A in the direction A D with a velocity which would carry it to D in the same time that it would descend by gravity to R. Also let A N represent in quantity and direction a third force, acting on the body for the same time, and equivalent to the force so often mentioned already as acting on the plane side. I need not say that A N is composed of all the successive forces acting on the plane side of the body, during its motion over dif- fereht volumes of air in the same time that the projectile force would carry it to D, and gravity to R. The fourth and fifth forces spoken of (1.) are already ac- counted for, and not estimable here (3.). Since these three forces act on the body at once, it will be found at the end of the given time at I (see Comp. and Res. of Forces,) the solid angle of the parallelipipedon opposite to A ; and, because the forces are not uniform, it will not have described the diagonal A I, but a curved line, as A O I. It is evident that the ele- vation of I, and consequently of the body, will depend on the magnitude of the angles which A D and A N respectively make with the horizon. By drawing the diagonal A P, which is equivalent to the forces of projection and gravity, (see Me- chanics, Comp. and Res. of Forces,) we may see that gravity contributes to augment the resistance to the plane side; for combined with the force of projection, it increases the action of, and thereby causes greater reaction to, the plane side. 1 1. I shall now mention what appear to me the causes of its return. When arrived at its greatest elevation the force of projection has ceased, and with it the forces generated by it. It is evident, however, that although the projectile force is spent, the gyration on its axis will not instantly cease, but continue for a few seconds (First Law of Motion). The only force now acting on the body is gravitation. You may not be aware that the angle of inclination, i. e. the angle which the plane side makes with the horizon, has increased very much, so much indeed that if it was projected at 40° or 50° it may have become 60° or 70°, the cause of which I may have occasion, perhaps, to explain in a future communication. Should it increase so far as to become a right angle, it is ob- vious that the body would instantly descend by gravitation. S34 On the projectile Weapon of the Native Australians, for in that case there would be no supporting power. But let it be granted that it has become only 60° or 70°, and we may easily perceive the effect that will follow. 12. When gravity begins to act on the body in these cir- cumstances, its plane surface impinges on the column of air beneath, the particles of which immediately react on the plane surface, and by this means cause it to deviate from the per- pendicular to the horizon, down which it had commenced to descend by the force of gravity. And because the plane sur- face is, at this juncture, removed from the projector, and that the resistance is against the plane side, the direction of its deviation from the perpendicular will be towards him. This occurs in the first instant of descent, the same in the second, and so on, until its return to the earth ; with this exception, that the body descends with a velocity increasing at every pointy as it retires from the highest (see Mechanics, Oscilla- tions of Bodies). Hence the amazing velocity with which it moves immediately before reaching the earth. I need scarcely add, that since the two forces causing its return are not uni- form, the line of its descent must be curved. 13. An additional cause of its returning is the direction (relative to the line of its motion, and relative to its plane side,) in which those particles impinge on its plane side, which pro- duce a greater effect than any of the other particles acting on the same side. The direction to which I allude is the angle of 54° 44?' mentioned above (9.). The annexed figure will render this much clearer than lan- guage can do. B E R is the curve through which it moves ; and each of the lines n a, r d, &c. will represent the angle 54° 44' at which the most powerful particles already spoken of act on the plane side of the body ; for when by the impact of the first series of the most powerful particles on the plane side, the position of that side becomes altered, it is manifest that a change will also be ef- R'b fected in the position, not in the magnitude of the angle, at which the next series of most powerful particles will act on the same side. And because this process continues in the manner represented in the figure, their tendency is evidently to make it return. 14. It will be observed that as the body descends, the angle of inclination gradually decreases, until the plane side becomes parallel to the horizon. The reason of this, and some other observations, which I intended to offer on the na- Mr. A. Smith on the Equation to FresnePs Wave-Surface, 335 ture of the ascending and descending curves, and on the angle at which the body ought to be projected, in order to return, I must defer, as I have already trespassed too far on your very valuable space. Should any of your readers misappre- hend my meaning, or look upon anything I have said as re- quiring explanation, I shall feel happy in affording any addi- tional elucidation in my power. Belfast, Jan. 20. 1838. B. D. LI 1 1. Method of finding the Equation to FresnePs Wave- Surface, By Archibald Smith, Esq,^ Fellow of Trinity College^ Cambridge, To the Editors of the Philosophical Magazine and Journal, Gentlemen, f WILLINGLY comply with the request of your Corre- -■■ spondent, that I should communicate to your Magazine the method of finding the equation to FresnePs wave-surface, which was published in the 6th volume of the Cambridge Transactions*. I shall do this as briefly as possible, indicating the principal steps; the intermediate steps will, I believe, offer no difficulty. If V be the length of the perpendicular from the origin on a tangent plane of the wave- surface and Im n its direction- cosines, a^, 6^, c^ the coefficients of elasticity ; the equation to the tangent plane is Ix + my -\- nz =: V (1.) and we have the two relations Z2 + 7^2 + n^ = 1 (2.) V m" n^ __ ^;2_a« + v^-b^ "^ v'^-c^ ■" ^ ••• ^^-^ To find the equation to the wave-surface we differentiate these equations, making /, m, w, v vary. Eliminating the differ- entials by the method of indeterminate multipliers, we get the following equations : A 7 B^ ^^ = ^^+ ^^2 (M y=.Am+^~j^^ (5.) Bw , , z = kn + ^_-^2 («.) -B.{(^.)%(^.)V(^.r} (7.) * See p. 78 and 261 of the present volume. 336 Mr. A. Smith 07i the Equation to Fresnel's Wave'Surface, From these seven equations the six quantities /, m, n, v, A, B are to be eliminated, and the resulting equation will be that to the wave- surface. Such an elimination would in general be quite impracti- cable ; in the present instance, and in many others of the same class, it is facilitated in a remarkable manner by the forms of the equations. The equations (4.), (5.), and (6.) multiplied by /, 7W, n re- spectively and added, give w = A (8.) The same equations squared and added, give T> If we put r^ for x'^ + 2/^ + ^^ j and for A the value just found, we shall find B = w (r*— i;^) (9.) If these values of A and B be substituted in equation (4'.) it may easily be put under the form — (Ir^^x v^). The same substitution made in (5.) and (6.) will give two similar equations ; and if these three equations be multiplied by ^5 2/, z respectively, and added, the right-hand side will be found equal to zero; and thus we get finally as the equation to the wave-surface. There is another form of the equation which is rather more easily obtained than the above, which will be found in a paper inserted by Mr. Gregory in the first Number of the Cambridge Mathematical Journal. The form I have given has this ad- vantage, that we may derive from it immediately the construc- tion by means of the ellipsoid ; for this I may refer to an article in the second number of the Journal just mentioned. Jordanhill, near Glasgow, Arch. Smith. March 6, 1838. t 337 ] LIV. Description of two Calculi composed of Cystic Oxide, By Thomas Taylor, M,R.C,S, To the Editors of the Philosophical Magazine and Journal, Gentlemen, T^HE unfrequent occurrence of calculi composed of cystic oxide, induces me to believe that a description of two specimens of that substance would not be unacceptable to some of your readers. They were found amongj a number of un- examined calculi in the museum of St. Bartholomew's Ho- spital, which, by the kindness of Mr. Stanley, one of the sur- geons of the establishment, and the anatomical lecturer, I was permitted to examine and arrange. The larger specimen weighed 740 grs. ; it was of an oval figure, somewhat flattened, measuring one inch nine tenths through the long axis, and respectively one inch four tenths and one inch one tenth through the two short axes. When sawn through it exhibited the confusedly crystallized struc- ture characteristic of this species; the crystals apparently radiated from the centre, their summits projecting at its ex- ternal surface ; these were not however sufficiently defined to render their form evident. The whole had a light yellow colour, its sp. gr. = 1*13. When heated before the blow- pipe, it emitted the peculiar odour of cystic oxide, and left a small ash, which was partially fusible. In all its other che- mical relations it entirely agreed with that substance. Ten grains of the sa wings yielded by analysis : Cystic oxide 9*10 Phosphate of lime 0*38 Phosphate of ammonia and magnesia... 0*10 Animal matter and loss 0*42 10-00 Uric acid could not be detected in it. As far as I am aware this specimen is the largest and finest upon record. Of the other the museum possessed only one half; it was of a lighter colour, and the crystalline structure was not so well marked. Crystallization appeared to have taken place from three points. It measured one inch seven tenths by one inch three tenths. Its exterior was coated in parts by a thin layer of the fusible calculus mixed with a little cystic oxide. Its chemical characters corresponded with the other, but when burnt, it left a much smaller residue, which was alkaline. Unfortunately no history has been preserved of either of these calculi, although there are strong grounds for believing Phil, Mag, S.3. Vol. 12. No, 75. April 1838. 2 I SS8 Prof. Johnston 07i Hatchetine, that the larger calculus was taken from the bladder of a young man after death, who during life had exhibited no symptoms of any affection of the urinary organs. Should this meet with your approval, its insertion in your ensuing Number will much oblige. Gentlemen, yours, &c., March 13, 1838. Thomas Taylor, New Bridge Street, Blackfriars. M.R.C.S. LV. On the Composition of certain Mineral Substances of Or- ganic Origin, By James F. W.Johnston, M.A., F.R.SS., L, and £., F. G.S., Professor of Chemist?'!/ and Mineralogy, Durham*. II. Hatchetine, T^HIS mineral is known to occur, though rarely, in con- -*- nection with the iron ores of the coal measures in Gla- morganshire, and in some of the Midland counties of England. The specimen to which the following description and analysis applies was from the former locality,' and I have been in- debted for it to the liberality and kindness of Sir David Brewster. It is transparent, yellowish, consists of thin laminae of a nacreous lustre, has the consistence of soft wax, is greasy to the touch; at ordinary temperatures has no perceptible smell, but when heated emits a fatty odour. Its specific gravity at 60° Fahr. is 0-916, and it melts at about 1 15° Fahr. I am in possession of too small a quantity to enable me to ascertain its boiling point. By a cautious application of heat it appears to distil over without change. Exposed to the air for a length of time it blackens on the surface, and becomes opake, and it is found in most cabinets in this state. When melted, the black particles, probably charcoal from the slow decomposition of the mineral, float in the fluid and exhibit much lustre. Boiling alcohol dissolves it very sparingly, and from the so- lution it is nearly all precipitated on cooling, ^ther in the cold also dissolves a very small quantity ; in boiling sether it is more largely soluble. On cooling, the solution coagulates into a mass of minute fibres (prisms), from which the aether may be separated by agitation or compression, and which have a crystalline nacreous lustre. In recent specimens the mineral is said sometimes to occur in large crystals, with the form of which I am unacquainted. After repeated boiling with aether there remains still a minute portion undissolved, • Communicated by the Author- MM. Pelouze aiid Richardson on Cyanogen. ?^39 mixed with the particles of charcoal by wMch its surface had been blackened. Concentrated and boiling sulphuric acid chars and decom- poses it. In boiling nitric acid it undergoes no apparent change. According to Sir David Brewster it polarizes light in patches. Of an uncoloured portion selected for analysis from the centre of the mass, 5* 14- grs. gave 15*97 of carbonic acid, and 6*765 of water. These quantities are equal to Experiment. Theory. 1 atom of carbon = 76*437 = 85*910 85*965 1 atom of hydrogen =12*479 = 14*624 14*035 88*916 100*534 100* The excess of hydrogen is to be attributed to the unusual quantity of moisture left in the oxide of copper, which the vo- latility of the substance prevented me from heating sufficiently high to permit the water to be wholly driven out. This substance therefore belongs to the group of which olefiant gas is the best known type, and it differs from pa- raffine chiefly in its tendency to crystallize, and to decompose and blacken by long exposure to the air, or by the action of concentrated sulphuric acid. In the last two properties it agrees with theMiddletonite described in the preceding Num- ber of this Journal, p. 261. Durham, March 1838. LVI. Researches upon the Products of the Decomposition of Cyanogen in Water*, By MM. Pelouze and RicHARDSON.f /CHEMISTS have possessed up to the present time but ^^ very incomplete notions respecting the alteration which an aqueous solution of cyanogen undergoes when exposed simply to the action of light. M. Vauquelin, who was occupied with this subject in 1818, found that besides ammonia, and a peculiar black matter, there was formed, by the action of cyanogen upon the ele- ments of the water, three distinct acids, viz. carbonic acid, * This note is the first part of an examination which we have under- taken upon the alteration which several azotized bodies undergo by the action of water, heat, «&c., and upon the state of the azote in charcoals of animal origin. t Communicated by Mr. Richardson. 2 I2 540 Products of the Decomposition of Cyanogen in Water. prussic acid, and a new acid which he considered as com- posed of cyanogen and oxygen. The opinion of M. Vauquelin upon the nature of this latter substance was solely founded upon theoretical views, for he had neither isolated his new acid, nor studied any of its com- binations. The experiments which we proceed to detail, authorise us to say, that M. Vauquelin had deceived himself in an- nouncing the formation of cyanic acid by the decomposition of cyanogen in water, and that the matter which he had con- sidered as cyanate of ammonia was a mixture of urea and ox- alate of ammonia. A solution of cyanogen in water, prepared in the ordinary manner, was exposed to the action of light, till all odour of cyanogen had disappeared. The new liquid had a strong smell of prussic acid; its colour was slightly yellow, and its reaction ijeutral. A black, flocky, light substance had fallen to the inferior part of the solution. It was collected upon a filter, and freed from all foreign soluble matters by washing with distilled water. After this purification it was slightly soluble in water and alcohol, insoluble in aether; soluble, on the con- trary, in acetic acid and the caustic alkalies, and possessed the property of forming true salts with the various bases. The small quantity at our disposal did not permit us to submit it to an examination as rigorous and extended as we could have desired. However, from the analysis of its com- bination with the oxide of silver we have reason to believe that its true composition may be expressed by the following formula : Ns C, He O4. A part of the liquid was boiled, and the vapour disengaged was conducted through lime-water. An abundant precipitate of carbonate of lime was formed, leaving no doubt that car- honic acid was formed during the decomposition of the cyano- gen in water. The remainder of the liquid disengaged during its concentration a quantity of ammonia and prussic acid. The dry residue had a slight yellow colour, and a saline, sharp taste. Treated with alcohol, it was divided into two nearly equal parts. The portion soluble in the alcohol pos- sessed all the characters oiurea. The residue, insoluble in alcohol, was oxalate of ammonia. From the analysis of these two substances and the minute examination of their properties, there can be no doubt re- specting their production in the spontaneous decompositicm of cyanogen dissolved in water. If M. Vauquelin had pur- sued the examination which he had commenced of the pro- Prof. Sylvester's Notes on the Optical Theory of Crystals, 341 ducts of this decomposition, he would, perhaps, have been the first to make the beautiful discovery, which fifteen years after- wards was made by M. Wohler in the artificial production of an animal matter; but the small quantity of matter upon which he operated, did not permit him to analyse completely a sub- ject to which he never afterwards returned. It is exceedingly curious to see a substance of such a sim- ple composition as cyanogen, a substance which is placed by its characters in the system of chemistry, not at the side, but in the very middle of the elements, giving birth, in reacting- upon water, to so many different products. In admitting for the black matter the formula Ng Cg Hg O4, we can explain the decomposition of cyanogen in water by the following equation : ' 1 atom urea N4 Cg Hg O^ 6 atoms prussic acid Ng Cg Hg 4 atoms carbonic acid C4 Og 2 atoms ammonia N^ Hg 1 atom oxalate of ammonia Ng Cg Hg O4 1 atom black substance Ng Cg Hg O4 ^22 ^22 Hag O18 LVII. Notes to Analytical Development^ S^c, By J. J. Syl- vester, of St. John's College Cambridge, Professor of Natural Philosophy in University College, London,'^ Note 1. IN the paper above adverted to, I showed that the meridian plane, i. e. the plane contaming the ray and normal, always passed through ^a line of vibration in the corresponding point. Now the line of force called into action by a displacement in the line of vibration clearly lies in this very plane; for the re- solved part of it lies in the line of vibration itself. Harmony and analogy concurred in making me suspect that as two of these four lines are perpendicular to each other, so are also the other two, or in other words, that the ray is always perpendicular to the direction of unresolved force. The following investigation verifies this conjecture. Let a:,y, z be the coordinates of a point taken at distance unity from the origin and in any line of vibration ; then the cosines of the angles made by the line of force with the axes are as a~ x: b^y: c'^ z respectively. Let a be the inclination between the line of vibration and the line of force, then * Communicated by the Author: see vol. xi. p. 461 etscq. and present volume, p. 73 et seq. 342 Prof. Sylvester's Notes to his Analytical Development cos 60 = — ^ "" ^/a'^x'^h^f^-c'^z^ Let 4/a*^2 + ^*/ + c*;s^ = P, then P^^ = u^ (sec co)^ Now let a, /3, y be the angles of inclination between the coordinate planes and the front in which the line of vibration lies, and A. some quantity to be determined. I have shown in proposition (3.) that if A. cos a, ■=: {a} — v^) x then will A cos /3 = (h^ — v^)y and X cos y — (c^ — t;*) z - ^2v''{a'x^ ^ b'^f +c^z^) + t;4 = P^ ~ v\ Again, /Jcosjt)^ (cosj)^ (cosy)n _ ^s . ^. . ^. _ j _ j __. (cos g)^ (cos /3)^ (cos y)^ Now m 4 = TT ~\o. 4^ = -X (cos Oif, p2_u4 u* (sec co) 2— I?* tr ^ ^ And in Mr. Smith's investigation of the form of the wave sur- face (already alluded to*) by great good fortune 1 find ready to my hand (cos a)2 (cos /3)^ (cos yY _ 1 (r) being the radius vector to the point whose tangent plane is parallel to the point in question. Hence (cot c)^ = ^-^,-— ,j = ^;,-^, _ P' (p) being the length of the perpendicular from the centre upon the tangent plane for p = v. Hence (cot oo)^ = the square of the cotangent of the angle between radius vector and normal. • Sec p. 78, 261, and 335. I of the Optical Theory of Crystals, 343 Or, in other words, the line of force is as much inclined to the line of vibration as the ray is to the normal. Now the normal is perpendicular to the line of vibration, and all four lines lie in one plane, .'. the ray is perpendicular to the line of force. Q. E. d. I may be allowed to conclude this long paper with a sum- mary of some of the most remarkable consequences which 1 have extricated from Fresnel's hypothesis. 1. The two meridian planes corresponding to any given radius are perpendicular to each other*. 2. So are the two corresponding to any given normal. 3. Every meridian plane bisects the angle formed by two planes drawn through the radius and the two prime radii. 4. It also bisects the angle formed by two planes drawn through the normal and the two prime normals. 5. Each meridian plane contains one line of vibration and the corresponding line of force. 6. The ray is perpendicular to the line of force. All these conclusions, except the fourth, are, I believe, original. The theory of external and internal conical refraction fol- lows immediately as a particular consequence from the third and fourth combined as already shown ; the same propositions also enable us to draw a tangent plane to any point of the wave-surface by mere Euclidean geometry. May not some of these conclusions serve to suggest to physical inquirers the question. Has the theory been started from the most natural point of view ?t University College, Feb. 24, 1838. Note 2. — Investigation of the Wave-Sufface, Since the appearance of the preceding parts, I have suc- ceeded in completing the self-sufficiency of my method by deducing the equation to the wave-surface from the expres- sions given in Prop. (5.) for the angles between a front and the principal planes in terms of its two velocities. If these angles be CO, ^, 4/ , and the two velocities v^ v^^, we found {a'b^){a''-c'') ^^ ^ /(a^-v,^){a''-v.;' cos cw = \ / ^^ '-L^ IL V {a'b^)(a^-c^) cos ^ = ./WE^nWE^ ^ V (b^-.a^){(^-b^) * 1 have defined the meridian plane to be that which contains radius vector and normal belonging to the same point. f This investigation supplies the step which Mr. Tovey was desirous should appear in the Magazine. 344 Prof. Sylvester's Investigation of the Wave-Surface, Let the tangent plane to the wave surface be written cos «. . cos <^ , cos ^f ^ / \ifc . x-\- . vH a? = 1 (a.) v^ v^ ^ ' v^ ^ • d cos j3/H-(c^-V)C?^ = 1 (3.) From(l.) A?^ + B>jj/= - C?^ (5.) From (2.) A y ^ + ^^ = - ^-^ ^ (6.) From (2.) and (1.) A{a^-c^)£ x + B {b^-c^)Yii/ = J (7. From (3.)and(4.) A{a^-c^-)^ + B(Z>^-c^)^ = c^ (8.) From (3.) and (6.) C^ c^ s^ - B* ^^^ - A^a^a;^ = ABxJ,(a^| + i^l) (9.) • In lieu of v, we might write v^^ in the denominator without affecting the result. ,,hatE£i_^=yit:.!)^-!i^ t Ob.er,e..hat_- = V.l;i^_/_ _,,„,,,„„„ fo, th, „3,. Mr. Jerrard on the Occurrence of the Form g . 345 From (7.) and (8.) C^ - B^ (6^ - c^f - A^ K " <^Y ^^ = AB^3/(-J+ |) x{a^-c'W--c') (10.) From (9.) and (10.) A B {a^-h') {a^-c^) [b^-c^)^y^ ^ a^c''- (a'-c*) (62-c2) C^c'^z'^ -(a\{b^-c^f-b''{a^-c^){b^-c^)) Wy" -.(fl«. [a^^c^f-a" (fl^-c^) (i^-c^)) k^x" r^a^c^-c^z'-c^y^-a^x^ (11.) From (11. )> interchanging («, ^, f) with (J, 3^, ^r) we have A B (6^-fl^) (62 -c^) (a2_c2) xy i-= b^c^-c^z'-c^ x'-b'^y^ (12.) Finally, from (11.) and (12.) we have (a^ c^ - ^2:=^, ^2 __ ^9 ^ ^rqry-qr^) X {b^c^-W^^^.y^-c^a;^ ^y^ + s;^) = («2_c^)(Z,2_^9)^2y i. e. [x" + «/^ + 2^) (a^ a;2 •\-b''y'^ + c" %^) —a^ (b^ + c«) + ^2-Z>^ (a2 + c2) /— c^ (6^ + «') ^^ The = " required. University College, March 5, 1838. LVIII. On the Occurrence of the form ^ in passing from ge- neral to particular Values of certain Algebraic Functions. By G. B. Jerrard, Esq,^ SUPPOSE that we have two equations for determining or, ar*»+A^*^^+ Bx"^-^ + V = 0 (1.) ^ = P + Q^ + R^2 + Lo;^ (2.) so that X- M3/>P>Q>R>-L). so that x^ 4,(3^,p,Q,R, ... D' A, B, C, ... V being constant quantities involved in the mean- ing of the functions <^ and v[/. Let us further suppose that P, Q, R, ... L are in such a manner dependent on certain equations of condition that we are able to foresee that the expression for x will be deter- * Communicated by the Author. 846 Mr. Jerrard on the Occurrence of the Form g, minate when m is general in value. If then it should appear that for a certain value of m the equation f/ = F + P''a: + P'"^ ... + ?("») x'"-'^ which arises from combining the equations (1.) (2.), would take the form 0 = 0 + Oo: + 0a?2,.. _j- Ox*^-\ in what light ought we to regard this result ? The expression for X will most certainly in this case assume the form but ought this to be regarded as the ultimate form for x ? May not the expression —- become interpretable by following the known methods for the treatment of such functions ; or rather, must it not be susceptible of an ulterior form ? To fix our ideas, let 7» = 4, A = 4, also let P=/aS), R=/,(S), Q=/3(S), y=f,{S), T=l. Accordingly we shall have ^ _ *jsi Then if 7^ = 0, F = 0, P" = 0, F" = 0, P'^ = 0, or, /4(S) = 0,/i(S)-D = 0,/3(S)-C = 0,/2(S)=0, S=0; that is to say, if the functions designated by fx^f the three axes of the ellipsoid being and A, B, C, constants, afterwards expressed by certain definite in- tegrals. He then remarks that every ellipsoid which verifies this formula is capable of an equilibrium when it is made to revolve with a proper angular velocity about the least axis ; for, in this case the Mr. Ivory on the Attractions of homogeneous Ellipsoids, 357 centrifugal force will be represented in quantity and direction by a line such that the resultant of this force and the whole attraction of the ellipsoid upon a point in the surface will be perpendicular to the surface. Lagrange had concluded that the equation (1), which re- sults immediately from his investigations, admits of solution only in spheroids of revolution, that is when A = A' and B = C ; but by ex- pressing the functions A, B, C in elliptic integrals, M. Jacobi has found that the equation may be solved when the three axes have a particular relation to one another. In order to ascertain the precise limits within which this extension of the problem is possible, and to determine the ellipsoid when the centrifugal force is given, the au- thor has recourse to the equations of Lagrange, which contain all the necessary conditions, and he deduces the equations A A f = ^-T+T^' /=C-3-p^,. . . . (2.) where / represents the intensity of the centrifugal force at the di- stance equal to unity from the axis of rotation ; and he remarks that these equations coincide with the equations of Lagrange. Substi- tuting for A, B, C certain definite integrals given in the Mecanique Celeste, he deduces three equations expressing the value of g, the ratio of the intensity of the centrifugal to that of the attractive force, one of these being expressed in terms of the density, and the other two in the form of definite integrals ; and then remarks that " these equations comprehend all ellipsoids that are susceptible of equilibrium on the supposition of a centrifugal force." He then applies these equations to the more simple case of the spheroid of revolution, where X = X' = /, and determines the value oil 7=2-5293, and the corresponding maximum value of g = 0*3370, and re- marks that, with respect to spheroids of revolution, it thus ap- pears that an equilibrium is impossible when g, or its value in terms of the density, is greater than 0*3370. In the extreme case, wheug is equal to 0*3370, there is only one form of equilibrium, the axes of the spheroid being A: and A: v/{l + (2*5293)2} or 2*7197 A; but when g is less than 0*3370 there are two different forms of equi- librium, the equatorial radius of the one being less, and of the other greater than 2*7197 k, k being the semi-axis of rotation. The number of the forms of equilibrium in spheroids of revolution, he remarks, is purely a mathematical deduction from the expression of the ratio of the centrifugal to the attractive forces ; and as this has been known since the time of Maclaurin, the discussion of it was all that was wanted for perfecting this part of the theory. Returning to the general equations of the problem, the author deduces the equations d

• M W W fe «• • g W '^ S ^ « S •uo^sog lo uo u:) ooooo-^o^"^"^Ti*oio^oco>o^-H(NOc«irir»oo CO«CN^O^lOO^O^■^lOOOa^'^I:^vo^^>C^Otoco coOcococO'^-^to-^cocO'^CDCOcocoococOTl0'^-<*u:) ■po90r^o©occioco (N-— ^^^^c»6^cb»^p^t^'o■^p

pc^'^•«!^^ b^c<»biocbbcbt^6o cocococorocO'^^'^'^cocococococococococO'^cOrorf'^Tjf'rl'T^ Op COCO coc^op C^OI t^ , c^(^^6t>.6^c^c^■^co<^^ COCOCOpc^^o<^^»pcoco<^^cpop i>qp i>.c» <>i o^db^br^ob 6^ob co«?o>^ uoTtro6>oob r^c^ cooi>oc-oo oooo*ot^r^r^^o^'^o^'*oo^o"oa^-HloO'^oc^oococ^ rN'O^t^^TS.oOrJ-^t^ ioio• C<"^^COCOOtO"-HOCOCO-H b b b b b b b^6^co a^a^6^a^6^6^a^6^6 b b^p^b^o^a3a)^ 2*2* OCOCOCOCOCOCIOirNC< 0, which requires that the resultant of X, Y, Z should be directed towards the interior of the fluid mass. But the pressure at the surface of a fluid in equilibrium does not always equal nothing. For what do we mean by the surface^ when we speak of pressure ? Not the geometrical sur- face, but the external layer of particles. The term pressure implies the contact of two molecules ; and the equation of fluid pressure at any point is deduced upon the supposition, that at the point two molecules are in contact. Therefore un- less we can show that the pressure upon the interior surface of the external layer is an infinitely small quantity, we cannot say that the pressure at the surface is equal nothing. Because there is no pressure at the geometrical surface, (for the con- ception of pressure has no place there,) we must not say that the pressure at the surface equals nothing ; for this would imply thai the analytical expression for the pressure at any point in the fluid becomes zero at the surface, which is not always the case, as we shall now show. In the cases of ordinary stable fluid equilibrium (for ex- ample the external surface in the instance advanced by M. Ostrogradsky), the pressure decreases as we approach the geometrical surface ; and the pressure on the internal surface of the external layer is an indefinitely small quantity, and is smaller the less the thickness of the external layer. Hence, in these cases, it happens, that the function expressing the value of the pressure does become zero at the geometrical surface. But in cases of unstable equilibrium of the nature of that of the internal surface in M. Ostrogradsky's example, the pressure increases as we approach the geometrical surface, and is greater the less the thickness of the outward layer ; but this layer must always have some thickness, for immediately we reach the geometrical surface, the conception of pressure vanishes, and the equation of fluid pressure has no existence. If we could discover a function which would represent both the magnitude of the pressure at any point of the fluid, and the fact that there is no pressure at the geometrical surface, this function would be discontinuous at the geometrical sur- face. This seems to be the explanation of the difficulty. In or- dinary cases of stable equilibrium (as has been shown) there is no actual necessity for these distinctions, though they may be very useful, even in those instances, to clear up our views. March 19, 1838. [ 387 ] LXIII. On the Dimorphisvi of the Chromate of Lead, By James F. W. Johnston, AM., FM.SS. L, ^' E., RG.S., Professor of Chemistry, University of Durham.* "OESIDES those substances which, like the biniodide of ^^ mercury and the carbonates of lime and of lead, are known to be dimorphous as individuals, there are other bodies, simple and compound, known to be dimorphous as groups, though the individual members of these groups have not yet been observed to assume more than one form. The analogous compounds of the tungstic, molybdic, and chromic acids, pre- sent groups of this kind. The tungstate and molybdate of lead and the tungstate of lime occur in square prisms, while the chromate of lead has hitherto been observed only in oblique rhombic prisms ; the general formula for all of them being R R. In my report on the present state of our knowledge in re- gard to dimorphous bodies presented to the last meeting of the British Association, and which will appear in the ensuing volume of their Transactions, I had already attributed this difference of form exhibited by the several members of the above, and many other analogous groups, to the existence of a true dimorphism ; and while I considered that such groups, being chemically analogous, might also be considered as cry- stallographically dimorphous or heteromorphous, I expressed my conviction that further observation would prove the se- veral members of these groups to be also heteromorphous, each individual assuming the forms already observed in any of the others. I am now enabled to confirm these views by a very interesting example. On a late visit to the cabinet of my friend Mr. Brooke, whose skill as a crystallographer is so highly and so de- servedly estimated, he showed me a small specimen of what he called molybdate of lead (crystallographically so) with the colour of the chromate. Of this specimen he has since kindly favoured me with a few minute fragments, in all not exceeding the fifth of a grain, but sufficient to enable me to determine that the beautiful red crystals were not molybdate having the colour of chromate of lead, hui chromate in the form of the mo- lybdate. Fused with borax the mineral gave in both flames a beautiful green bead ; with microcosmic salt a bead which at a high temperature was nearly colourless, as it cooled became reddish brown, and when solid was of a beautiful green, A larger addition of the mineral rendered the glass opake, but did not blacken it. It dissolved without residue in nitric and * Communicated by the Author. 2 M 2 388 Prof. Johnston on the Dimorphism of Chromate muriatic acids, giving with the latter a greenish solution, and on evaporation chloride of lead mixed with a green substance (chloride of chromium ?). From these characters there can be no doubt that the sub- stance is chromate of lead. The specimens on which these minute red crystals occur is from the Bannat. None of the crystals appear to exceed the sixteenth of an inch in length, and they rest on a thin yellow coating which resembles molybdate of lead. Besides the small specimens he possesses Mr. Brooke informs me he has never seen but one other. He has measured two of the crystals, and satisfied himself that in form they are identical with the molybdate. We are justified therefore in including the chromate of lead among known dimorphous bodies, and in more confi- dently anticipating that the analogous tungstates and molyb- dates will prove so also. A strict examination of the speci- mens already existing in cabinets may be expected to fill up several of the gaps. In the following table: Oblique Rh. Prism. Square Prism. Chromate of lead. Tungstate of lead. Tungstate of lime. *Molybdate of lead. Common form. unknown. do. do. Rarer form from Bannat. Common form, do. do. There is another member of this group, the tungstate of iron and manganese (wolfram) which, though represented by the formula Fe Tu + Mn Tu, in which the bases are isomor- phous, yet crystallizes in a form different from either of those above mentioned, l^he two oblique rhombic prisms have in wolfram M, M = 101-5 P, M = 110^50' in chromate of lead = 93° 30' = 99° 10' We have here therefore a third form in which the members of this group may possibly crystallize. As wolfram however is a double salt, it is equally possible that this third form may result from the union of the other two. A square prism of tungstate of iron, with a less oblique prism of tungstate of manganese, may be capable of producing the more oblique prism of wolfram, or the union of the two salts in some other way may produce the third form, without rendering it abso- lutely necessary at present to have recourse to a trimorphism. In a former paper on the dimorphism of baryto-calcitef, 1 • I need not draw attention to the link which this new fact affords for connecting the molybdic with the sulphuric and other analogous acids, f Lond. and Edin. Phil. Mag., vol. vi. p. 1. of Lead ^ and on the Composition of Ozocerite. 389 suggested a similar solution for a difficulty of a similar but less striking character. At the same time it should be ob- served that there is nothing in the idea itself of a bod}' as- suming three or more incompatible forms which should in- duce us to reject it. It is the absence of direct propf of the fact which alone makes it prudent, in the present state of our knowledge, to endeavour to explain away appearances such as that presented by the group we are considering. We should however expect to find wolfram in the two other forms, even if its own special form do not belong to the group of simple tungstates, chromates, and molybdates. It has indeed been met with frequently both at Huel Maudlin in Cornwall, and Schonfeld in Saxony, in square prisms, or octohedrons; but these have generally been considered pseudomorphous, — as mere casts of former crystals of tungstate of lime. I have not seen any of these crystals, and cannot therefore judge of the evidence on which this opinion rests; but as there appears no reason why wolfram should not in favourable circumstances assume the form of the square prism, it is not unworthy the attention of mineralogists to examine how far these supposed pseudomorphous crystals are really and always so, Durham, March 1838. Note, — Since the above paper was written I have seen some of the octohedrons of wolfram from Huel Maudlin, and externally many of them are perfect; internally, however, they are often more or less hollow, exhibit no cleavage, but a structure radiating from the surface inwards, while the in- terior of the hollows is often studded with minute brilliant terminal facets. These characters appear to justify the con- clusion that they are pseudomorphous. Their interior cavity would seem to imply that they are also epigene, and that, as in the case of some of the Chessy malachites, the change has commenced on the exterior of the original crystal. LXIV. On the Composition of certain Mineral Substances of Organic Origin. By James F. W. Johnston, A.M., F.R.SS. Lond, and Ed., F.G.S,, Professor of Chemistry and Mineralogy, Durham.* HI. Ozocerite from Urpeth Colliery, near Newcastle-upon-Tyne. T^^HE attention of chemists and mineralogists has for several ^ years past been drawn to a species of fossil wax found in * Communicated by the Author. 390 Prof. Johnston on the Composition of certain Moldavia*, in sufficient quantity to be employed for oecono- mical purposes, and to which the name of Ozocerite has been given. This substance is of a brown colour, of various shades, has the consistence and translucency of wax, a weak bitumi- nous odour, sometimes a foliated structure and conchoidal fracture, and can be reduced to powder in a mortar. In burning, it emits considerable light, and is said to be used for the manufacture of a species of candles. The chemical and physical properties of this substance were first examined by Magnus [Ann, de Chem. et de Phys., Iv., p. 218) ; more lately by Schrotter [Bibliotheque Univ., May, 18S6); and most recently by Malaguti {Ann. de Chem., Ixiii. p. 390) ; who agree in representing it as a mixture of several substances, differing in their physical properties, yet possess- ing the same ultimate chemical constitution. The occurrence of a fossil body, possessing many of the characters of Hatchetine, and having much resemblance to the fossil wax of Moldavia, in a coal mine in this neighbour- hood, where no doubt could exist as to its origin, has afforded me an opportunity of adding to our knowledge of this class of mineral compounds, while it seems to indicate pretty clearly their common organic origin wherever they may occur. In driving through a trouble in Urpeth Colliery, at a depth of about 60 fathoms from the surface, this substance was found in cavities near the sides of the trouble, and sometimes in the solid sandstone rock; it occurred in considerable quantity, and was sufficiently soft to be made up into balls by the workmen. The specimen sent to me by my friend Mr. Hutton, of Newcastle, is soft, unctuous, sticking to the fingers, and giving a greasy brown stain to paper; semi-transparent; by transmitted light, of a brownish yellow colour ; by reflected light, yellowish green and opalescent ; having a slight fatty odour, more perceptible when the substance is melted. It fuses at 14<0° Fahr., attains its greatest fluidity at about 160°, and begins to boil at 250°. It distils without apparent de- composition, the colourless oil which passes over concreting as it cools into a colourless unctuous mass. As it distils, however, the boiling point of the residue rises very consider- ably, and it becomes darker coloured. Boiled in a retort with * It is found, according to Dr. Meyer, at the foot of the Carpathians near Slanik, beneath a bed of bituminous slate clay, in masses sometimes from 80 to 100 pounds weight. Not far from the locality are several layers of brown amber. It is associated with the gres bigarre, with rock salt, and with beds of coal. Mineral Substances of Organic Origin, No,IIL Ozocerite, 391 water, it is also volatilized in small quantity, and floats like wax on the water which collects in the receiver. Heated over a lamp in a platinum spoon, it takes fire, and burns with a pale blue, surmounted by a white flame, having little smoke, and leaving no residue. It undergoes no apparent change when boiled in concen- trated nitric, muriatic, or sulphuric acid. Alcohol, even ab- solute and boiling, dissolves it very sparingly. The solution is rendered milky by water; and by spontaneous evaporation, deposits the dissolved portion in white flocks, ^ther, in the cold, dissolves about four-fifths of the whole, giving a solution which, like the substance itself, is brown by transmitted light, and by reflected light exhibits the greenish opalescence, ob- servable in the ozocerite of Moldavia. The solution, by spon- taneous evaporation, deposits the dissolved portion in brown flocks, which, at 102° Fahr., melt into a yellow brown liquid. The mass, on cooling, presents the external characters of the original substance, but has less consistence and density. Its specific gravity is 0*885, and it melts at 102° Fahr. A further small portion of the brown undissolved matter is taken up by boiling aether and alcohol. Obtained by evaporation from these solutions, this second portion is colourless, or of a pale yellow ; has the appearance and consistency of wax, and melts at 136° Fahr., — about 16 degrees lower than the fusing point of bees*-wax. The remaining portion, which is almost insoluble in boiling alcohol and aether, has a dark brown colour, and the consistence of soft wax ; its density is 0*965 ; it melts at 163° Fahr., and boils at a temperature above 500° Fahr. The vapour has a peculiar and slightly bituminous odour. It con- stitutes about one-sixth of the mineral mass. As it occurs in nature, therefore, this substance contains at least three several compounds, agreeing in their indifference to acids, but differing in physical properties and in their rela- tions, especially to aether. The following table exhibits a comparative view of the properties of the mixed mineral, — of its three constituent parts — of the specimens of fossil wax from Moldavia, examined by Schrotter and Malaguti — and of the substance obtained from it by the latter on distil- lation. S92 Prof. Johnston on the Composition of certain How obtained, or where. Colour. Consistence. Density. I. Ozocerite Found native in Brown. Hard, brittle. 0-953 at 15° C. (Schrotter). Moldavia. II. Ditto A. Ditto. Ditto. Ditto. 0-946 at 20-50 rMalaguti). B. By distilling A. 0. Ofwai. 0-904 at 17°C. III. Do. from Urpeth. A. Urpeth Colliery. Brown . Of tallow. B. From A, by cold aether. Ditto. Ditto. 0-885 C. From residue, by boiling aether. Yellow. Of soft wax. p D. Residue,after boil- Dark brown. Of wax. 0-955 ing A in aether. The fossil wax examined by Magnus, seems to have been identical with that of Malaguti, only it melted at 82° C. The inspection of this table shows that these mineral pro- ducts contain at least four substances, possessed of different properties, chemical and physical, of which three are present in that from Urpeth Colliery. 1. One charred by sulphuric acid and insoluble in aether. — (//. Malaguti.) 2. One soluble in cold aether. — (/. and IL B.) 3. One soluble in boiling aether, and sparingly in boiling alcohol.— (//. B. III. C.) 4?. A residual portion of greater density scarcely acted on by either of these menstrua. — (///. D.) The different substances composing the ozocerite appear as I have already stated to be identical in chemical constitution, being entirely composed of carbon and hydrogen, in the same proportions as in olefiant gas. That the substance from Ur- peth Colliery contains no oxygen, is proved by its not affect- ing the lustre of potassium, when melted along with it. The carbon and hydrogen were ascertained by burning with oxide of copper. 1. 8*43 grs. of the crude mass, freed by fusion from ad- hering earthy matter, gave 10-69 grs. of water, or 1*187 grs. of hydrogen. 2. 5*4:7 grs. of the matter taken up by aether, gave 6*92 grs. of water, or 0*77 grs. of hydrogen. .*}. 5*84- grs. of the same gave 7*39 grs. of water and 18*32 grs. of carbonic acid. 4. 5*47 grs. of the same gave 6*72 grs. of water and 16*58 grs. ofcarbonic acid. Mineral Substances of Organic Origin. No. III. Ozocerite, 393 Melts at Boils at In iEther. Action of hot sul- phuric acid. 62°C. = 141-6° F. 84°C. = 182°F. 56° to 51° C. = 133° to 134° F. 60°C. = 140°F. 39°C. = 102°F. 58°C. = 136°F. 73°C. = 163°F. 210° C. =410° F. 300OC. = 572°F. 30O°C. = 572*' F. 121° €.=.= 250° F. Above 260° C. = 500° F. Dissolves. Almost insoluble. In boiling aether, very soluble. Largely soluble. Wholly soluble. Soluble in boiling aether. Very sparingly so- luble in boiling aether. Chars a portion of it. ■> 0 0 0 0 These results give for the crude mixed mineral, and for the portion soluble in aether, the same composition. Hydrogen Carbon... 1. 2. 3. 4. 1409 85-81 14-07 85-83 1406 86-80 13-649 83-812 100 100 100-86 97-461 The ratio of the elements in the fourth analysis is that of atom to atom ; the loss I attribute to the pumping out of a portion of the substance from the tube along with the moist- ure contained in the oxide of copper, the sand with which the tube was warmed in this experiment having been too hot for a substance boiling so low as 250° Fahr. The small portion of matter at my disposal prevented me from subjecting to analysis either of the other compounds contained in the crude mass ; the composition of this mass, however, as exhibited in No. I., shows that these also must contain the elements in the same proportion as the matter actually analysed. The following table shows also the identity, in chemical constitution, of these several substances, with the different varieties of Ozocerite from Moldavia. Hydrogen Carbon... Atoms. Equiva. lants. Per cent. Calculated. Ozocerite. | Magnus. Schrotter. Malaguti. Fm.Urpeth. 1406 86-80 1 1 12-479 76-437 14-0349 85-9651 1315 85-75 13-787 86-204 13-95 8607 88-961 100- 98-86 99-991 100-02 100-86 394 Prof. Johnston on the Composition of certain The elementary composition of these different substances, therefore, is identical, and is the same as that of olefiant gas. The ozocerite found in Urpeth Colliery must have had its origin in the coal strata. Emitted, in the form of vapour, and carried along by the lighter gas (fire damp), given off' at the same time, it would pass through the trouble, on its way to the surface, and be partly condensed in the cavities, and other cool places it came in contact with. It is highly probable that the other varieties of fossil wax may have been derived from a similar source. In considering the inflammable and explosive substances existing in coal mines it is usual to limit the attention solely to the permanent gas given off", without adverting to the pos- sibility of other substances, of a volatile nature, being also emitted in the state of vapour. The occurrence of this variety of Ozocerite, in Urpeth Colliery, shows us that the light carbu retted hydrogen sometimes carries along with it other volatile substances, and there is strong reason for believing that the combustible portion of the atmosphere of our coal mines rarely, if ever, consists wholly of this light gas. To show the Proteus-like character of the compounds of carbon and hydrogen, in the ratio of atom to atom, and how little che- mical analysis can avail directly in determining the total abs- ence of these substances, I subjoin a table, exhibiting the cha- racteristic properties of the numerous bodies we are already ac- quainted with, in which the elements exist in this proportion. state at 60 Becomes solid Density of How obtained, or where. degrees. Density. or liquid at Boils at gas or vapour. Sweet oil of wine. In preparing aether. Oily liquid. 0-917 Solid at 31° F. 536° F. p Solid oil of wine. Ditto. Prisms. 0-980 Liq. at 230° 500+ p Solid oil of roses. In oil of roses. Crystalline plates. 9 Do. at 95° 536° to 572° p Paraffine. From wood, coal, and animal tars. Ditto. 0-87 1 o to 111° "i ? Naphtha. From natural wells, and from coal tar. Liquid. 0-75 to 0-78 p 176° to 212° 2-833 Methylene. Exists in wood spirit. Gas. 0-490S ? 9 0-4903 Olefiant gas. By heating alcohol with twice its bulk Gas. 0-9806 of sulphuric acid. 9 9 0-9806 Faraday's light liq. By compres^ oil gas. Ditto. 1'9612 Liq. at 0° Below 32° 1-9612 Cetene. Distilling aethal with phosphoric acid. Oily fluid. ? ? 527° 7-844 Elaene. C Oleene. I Distilling metaoleic Ditto. p 230° 4-488 and hydroelaic acids. Ditto. "> 131° 2-875to3-02 Hatchetine. Found native. Solid 0-916 Liq. at 115° ? ? Ozocerite. Ditto. Ditto. 0-885 to 0-955 Liq. from 102° to 182° 250° to 572° ? Caoutchene. Distill'^ caoutchouc. Liquid. 0-65 at Liq. at 14° 58-2 ? Heveene. Ditto, or from caout- chouc by sulp. acid. Dense do. 0-921 at ? 579° p Mineral Substances of Organic Origin* No. III. Ozocerite. 395 A glance at the second column of this table shows that se- veral of these substances are obtained from the products of the distillation of coal ; and though it has not been demon- strated that any of them actually exist ready formed in the mass of the coal itself, yet the very low temperature at which some of them are given off lends to this opinion a considerable degree of probability. Reichenbach states that bituminous coal, by distillation with water, yields 1 •320,000th of an aethereal oil, which is identical with native naphtha; and he concludes that the naphtha and petroleum springs of Persia, India, Italy, and South America, have their origin in the slow distillation of large beds of coal, by the ordinary heat of the earth. The fossil wax of Moldavia, and the hatchetine of England, are probably derived from vegetable matter by a like agency. Naphtha is a comparatively dense fluid, requiring a tem- perature of upwards of 173° Fahr. to boil it; and, therefore, unless present in large quantity, it will rarely escape from the coal so rapidly, as alone to render the atmosphere combust- ible; but, suppose the very light liquid discovered in oil gas to exist in the coal, it will at once escape as a highly inflam- mable gas, and materially injure the atmosphere. Because such substances have not hitherto been observed in the air of mines, we ought not hastily to conclude that they do not exist, ready formed, in the great laboratory of nature. The diffi- culty of detecting them in a limited portion of gaseous mat- ter will, probably, long present insuperable obstacles to the analytical chemist, while the more we learn of the carbo- hydrogens the more likely it appears that several of them should be occasionally present in the air which circulates through mines of bituminous coal. The common fire damp requires, for its perfect combustion, ten times its bulk, the vapour of Faraday's light liquid thirty times, and that of naphtha forty-five times its bulk of common air. A very small portion of either of the latter, therefore, would render an atmosphere dangerous. The sudden out- burst of a small reservoir would pollute a working previously considered safe, and give rise to an explosion where none was considered possible. In a district of country like the north of England, where rich bituminous coal is so abundant, where mines are worked at the very verge of the inflammable state, and where the most serious accidents from explosions occa- sionally occur, it is of importance, I think, that the probable presence of such substances, in the state of vapour, should be taken into account. Where the coal is richer than usual, and where troubles occur in which these compounds, as at Urpeth, may exist in a liquid or solid state, the rapid escape of com- 396 Prof. Johnston on certain Mineral Substances, ^c. bustible matter may be anticipated ; while the probability of such escape affords a rational explanation of those sudden and unexpected emissions of gaseous matter which have occasion- ally been followed by consequences so disastrous*. An observation familiar to practical men in the English coal fields leads to the same conclusion. In mines where can- dles or open lamps are used, it is by the appearance of the flame that the miner judges of the purity of the atmosphere, and the presence of combustible matter. When little inflam- mable gas is mixed with the air, the flame carries over it a very short pale blue head^ which increases in length as the quantity of the carbo-hydrogen increases, until the whole atmosphere becomes one explosive mixture. But in different coal fields, the length of head, as it is called, which indicates an approach to the explosive state, is very different. In the Newcastle and Leeds coalfields 1 finches indicate danger; in S. Wales 4 or 5 in. are not unusual. The colour of the head is also a criterion by which the miner judges; when blue, combustible matter is present, and an explosion is to be feared ; if brown and muddy, carbonic acid is suspected, and the danger is less. Though no particular conclusions can be drawn from these observations, yet the general result does force itself upon us, that various compounds of carbon are at different times present in the atmosphere of coal mines and in various quantities ; and that sudden explosions may often be caused by the escape from cavities in the coal strata of other compounds than that usually called the fire damp, and to which all the mischief is usually attributed. Durham, March 1838. Note. — I have just seen in the possession of Prof. Graham, of University College, a candle formed of a substance said to be found in considerable quantity in the coal mines near Linlithgow in Scotland. It resembles in every respect the Ozocerite candles of Moldavia. The substance is dull brown, and after fusion almost black, reflected and reddish brown by transmitted light; mass opake but translucent at the edges and in thin layers ; is greasy to the touch (like Hatchetine), easily scratched by the nail, has a conchoidal fracture, and when cold has no perceptible smell. [ may here mention also that the Middletonite described in a former paper, has since been met with in the mass of the coal in the Newcastle coal-field. May not this substance be the resin of the trees of the car- boniferous aera more or less changed ? — April 16. [* Another explanation had previously been given by Mr. Hutton,in fol- lowing up an idea originally suggested we believe by Dr. Paris : see L. and E. Phil. Mag., vol. ii. p. 303 ; and Paris's Life of Davy, p. 395. Both are probably true. — Edit.] [ 397 ] LX V. Sequel to an Essai/ on the Constitution of the Atmosphere published in the Philosophical Transactions for 1826; with some Account of the Sulphurets of Lime. By John Dalton, D,C,U, F.R.S. Sfc, [Continued from p. 168, and concluded.] On the Quantity of Oxygen in the Atmosphere, SINCE the commencement of the present 'century it has been ascertained beyond dispute that the chief constitu- ents of the atmosphere, oxygen gas and azotic gas, are in the same proportion in all countries and at all times, except when influenced by local circumstances; namely, 21 percent, of volume of oxygen, and 79 per cent, of azote, neglecting frac- tions : other elements are found in the atmosphere, but they are comparatively insignificant in quantity, namely aqueous vapour, carbonic acid, &c. The experiments have generally been made on air collected at the surface of the earth ; and it may be remembered that I have endeavoured to prove in various essays that the diffusion of gases one amongst another as well as iii vacuo, is owing to the repulsive powers peculiar to the particles of each particular gas, otherwise we should never have the feeble efforts of carbonic acid and aqueous vapour diffusing those elements against the immense pressure of the atmosphere. The principle I contend for has, I be- lieve, obtained general assent; but I apprehend few have been aware of the consequences. If we suppose a carbonic acid atmosphere of 15 inches of mercury pressure and a hy- drogen atmosphere of the same pressure, together constituting a mixture of the two amounting to 30 inches of pressure, were to surround the earth, I think no one would hazard a con- jecture that these two would be found in equal proportions at every elevation in the atmosphere ; yet a similar supposition seems prevalent with regard to our present atmosphere of oxygen and azote. It has been an object of investigation with me for many years to find how the fact stands in this respect ; that is, whether the oxygen is more abundant relatively in the lower strata of the atmosphere than in the higher, as it ought to be in a stagnant column ; or whether the constant agitation of the atmosphere and the predominant mechanical power of the azotic part of it do not prevent that equilibrium which a stagnant mixture of aerial fluids of different specific gravities would effect. From the experiments about to be related, I have reason to believe that the higher regions of the atmosphere are somewhat less abundant in the proportion of oxygen than the lower, though the reverse might be ex- pected from the enormous consumption of oxygen by daily processes on the surface of the earth, when we know of no 398 Dr. Dalton on the Constitution of the Atmosphere, proportionate consumption of azote. It appears, however, that the disproportion of the two elements at different eleva- tions is by no means so great as theory requires ; and there- fore we must conclude the unceasing agitation of the atmo- sphere by currents and counter-currents is sufficient to main- tain an almost uniform mixture at the different elevations to which we have access. The subject is one involving an important principle. I have kept it continually in view for the last forty years, and have made innumerable experiments with a view to its elucidation. As the value of such experiments depends much upon a thorough acquaintance with the nature of the operations and the several sources of error to which they are liable, it may be needful to point out certain particulars, v/hich, as long ex- perience has taught me, require attention in order to secure a due approximation to accuracy. I allude more particularly to the use of Volta's eudiometer as applied to determine the proportions and quantities of oxygen and hydrogen gases. 1. Hydrogen gas procured over water is sure to contain some common air, whether the water has been previously boiled or not; it arises out of the water and may amount to 1 or 2 per cent. ; the same observation applies to oxygen gas ; the proportion of oxygen and azote is usually that in common air nearly. When a phial of hydrogen gas, by long keeping or by accident, has acquired a portion of common air, and then stood some weeks after, the oxygen seems to diminish, either by slow combustion or by absorption in the water, and so leaves the azote and oxygen in another proportion to that of common air. Before using such hydrogen the oxygen in it should be tested by nitrous gas, and the percentage of hy- drogen by oxygen gas. It is best not to rely too much upon hydrogen taken from a bottle half filled with water. ^. Oxygen gas, and others, will show carbonic acid by send- ing them up through a narroweudiometer tube filled with lime- water, provided the acid gas amounts to | per cent, of the ori- ginal; but it does not show any carbonic acid in this way in at- mospheric air, though the acid is always present to the amount perhaps of y qVo^^ P^^^* '^^^ proportion of pure oxygen in any sample containing from 90 to 100 per cent, of that gas, may be found either by hydrogen gas or nitrous gas; and if great accuracy is required, I recommend testing it both ways, as has already been mentioned under the head nitrous gas. 3. The gradual deterioration of oxygen, hydrogen, nitrous gas, common air, &c. when by use the phial became j, ~, or I filled with trough water, is a circumstance by no means to be overlooked. The entrance of water that has been some- and on the Sulphur ets of Lime. 399 time stagnant in the cistern, though preserved carefully from any material impurities, always affects the remaining air, though the phial be well corked and immersed in a cup of water. The cause is obvious to those acquainted with the laws that regulate the absorption of gases by water. The common air in the water (the quantity of which varies much as to the oxygen part) is continually either making its escape into the incumbent air of the phial, or this last air is entering the water, so that the degree of purity is continually changing in a small degree. This renders it necessary to test the actual state of this gas after it has been some time in the phial, be- fore we recommence the use of it. A phial of air may be pure at first, and only 90 per cent, at its conclusion. I have known samples of common air kept in bottles at first contain- ing 21 per cent, of oxygen, and after some months a small residue was found to contain only 19 per cent. 4. It may not be improper here to relate some unpublished results which I formerly obtained when experimenting on subjects here discussed. In my memoranda for 1816, I find that I took water well boiled (supposed | of an hour or more) and then poured it gently into a Florence flask, filling it up into the narrowest part of the neck, and left it so, exposed to the atmosphere for three days without any agitation. At the end of this, 2700 grains of water imbibed 49 grain measures of atmospheric air by agitation, which is about f of a full share; hence j of a full share must have been, both the air that was left in after boiling, and that acquired from the atmosphere in three days by absorption from the small ex- posed surface. Water boiled in a kettle for three or four minutes, then suddenly cooled and transferred without agitation into a bottle containing 2700 grains, and then agitated with atmospheric air, imbibed 32 measures, which are about half a charge; whence it may be inferred that water boiled for three or four minutes loses about half of its air. I boiled a kettle full of water for a quarter of an hour; let it stand a day or two to cool, then transferred it carefully by a siphon into a cylindric jar of 8 inches diameter and 10 inches deep; afterwards drew off daily by a siphon 2700 grain mea- sures from the middle or near the bottom of the jar, and charged it with air to the full by agitation. The bottle of water imbibed The first day ... 16 measures. The second day 15 measures. The third day.. 12 measures. The fourth day 10 measures. The fifth day ... 10 measures. 400 Dr. Dalton on the Constitution of the Atmosphere, The sixth day 9 measures. The seventh day 4 measures. ( '^^'t ^^^^J ^^^^" "'^^'' •' ( the surface. The eighth day 7 measures. *! These portions taken up The ninth day ... 9 measures. > consisted nearly one The tenth day ... 7 measures. J half of oxygen. The fifteenth day 2 or .? measures. From these experiments it would appear that by boiling water briskly for three or four minutes, about' half of the at- mospheric air previously in the water escapes along with the steam. But it requires much longer boiling and keeping the atmospheric air as much as possible from the surface of the water to get the rest of the air expelled. It is never all ex- pelled by boiling, except in the construction of a good water hammer. Any one air not chemically combined with water is easily and effectually expelled from it by repeatedly agita- ting the water with another kind of air. It also appears that water deprived of its atmospheric air, if kept at rest, acquires the air again slowly, and more so if the surface exposed is small. But if violent agitation of the water, so as to mix the atmospheric air and it intimately together, be used, the full impregnation is effected in one or two minutes, as I have elsewhere shown. Trough waters being mentioned above (3.) it may be well to explain some of the circumstances affecting it. The waters I use for the chemical trough is rain-water ; it is preferable to pump water by its freedom from carbonic acid and earthy salts ; it is slightly coloured at first when drawn from the cis- tern, but it soon becomes clarified by standing : my trough contains about nine gallons when in work. I take great care to put nothing in it which can materially affect its purity ; small portions of lime water and of some iron and other salts are the chief impurities which are admitted ; no sulphurets or hydrosulphurets are allowed to enter, and very little of either acids or alkalies. I examine the state of the water occa- sionally ; lately, after it had been more than half a year in the trough, though not very frequently used, I had the curiosity to examine its state before the trough was emptied. The water was neutral by the colour test; it contained about 50 grains of saline matter in the gallon ; it was transparent, but slightly milky; prussiate of potash gave sensible blue; oxa- late of ammonia, muriate of barytes, and carbonate of soda produced a white precipitate. The taste was like that of earthy pump water. It had its full share of azotic gas, but rather less than half of its share of oxygen gas; that is, it had about 4 or 5 cubic inches of azote in the gallon, and only 1 cubic inch of oxygen. and on the Sulphurets of Lime, 401 In the following train of experiments on the oxygen in the atmosphere I have mostly used from 50 to 70 measures of hy- drogen for 100 air, unless otherwise mentioned. Possibly this may not be thought the best proportion for securing the com- plete abstraction of the oxygen. The limits are, 100 air with 42 of hydrogen for the minimum, and 100 air with 170 hy- drogen for the maximum. In the former case the hydrogen is barely sufficient for the oxygen ; in the latter case the oxy- gen is barely enough to admit of a complete combustion, be- ing only y^^th of the mixture. Perhaps the best proportion would be 100 air to 100 hydrogen to ensure complete com- bustion, because it is about the mean of the two extremes ; but it must be considered that if the hydrogen should contain even a very small portion of oxygen, the whole of it in 100 mea- sures would be included in the atmospheric oxygen, so that in practice it would probably be safest to use a mean between 40 and 100 of hydrogen. I have mostly endeavoured to keep between 50 and 70 of hydrogen for 100 air. Experiments on the Quantity of Oxygen in Atmospheric Air, Air from the Summit of Helvellyn*, July 14, 1824. A phial, containing about half a pint, was filled with water at a clear rivulet on the ascent : this was emptied at the summit and well corked ; the cork was drawn at the foot of the moun- tain in a trough of clear running water, when a quantity of water was found to enter corresponding to the increased pressure of the atmosphere. The phial was then corked and inverted in a cup of water, and the air analysed a week afterwards. Average of four experiments on this air"! 20*70 oxygen with hydrogen, about 50 to 100 air, gavej per cent. Average of four experiments of the common air taken in Manchester at the time of the analysis, and with same phial of hydro- gen and same proportion, gave Average of seven experiments on Helvellyn^ 20*58 oxygen air made a day afterwards, gave J percent. Average of seven experiments, on air from ^ ^- an open place in the town next day with > ^ yg^^ u J I per cent, same hydrogen, gave J ^ * This mountain, situate at the head of Uilswater, separates Cumber- land from Westmoreland ; its height above the sea, which lies to the S.W., and from which it is distant about 20 miles, is upwards of 3000 feet; it is surrounded by other mountains, mostly of less elevation. Phil. Mag, S. 3. Vol. 12. No. 76. May 1838, 2 N ^20*88 oxygen per cent. 402 Dr. Dalton on the Constitution of the Atmosphere^ Average of eight experiments on the country*^ air three miles from Manchester, July [ p, 29, with same phial of hydrogen, which )> ^^78^^ now manifested a very slight trace of ^^^ ^^" * oxygen, gave ...J 1824', November 23. — Barometer 28 inches, very low. Ap- prehending that this circumstance, attended by rain and a high wind S.E., might have some influence on the proportions of the atmosphere, I made the following experiments. Average of six experiments gave 20*75 oxygen per cent. When the remainder of this air had been kept five months in the bottle, it then yielded on an average of three experi- ment 20*67 oxygen per cent. 1825, January 8. — Barometer 30*94, extremely high, after a week of calm weather. Filled a bottle with air from the town. Average of four experiments with two parts air and one hydrogen gave 21*12 oxygen per cent. The remainder of this air, kept till August same year, gave 21*1 oxygen percent. June 8. — Average of four experiments from air in the town gave 20*97 oxygen per cent. ; barometer 29*90. June 10. — Air from a field near the town, barometer being 30*30, thermometer 70°, wind S. W. ; sunny and sultry. Two parts of the air with one of pure hydrogen being mixed, the average of six experiments gave 20*58 oxygen per cent. June 14. — Mixed some pure azotic gas with oxygen gas, which was marked 90 per cent, pure, in such proportions as to make a mixture of 21 per cent, oxygen. On trial with hydrogen the mixture gave, first experiment 21 + oxygen per cent.; the second experiment 20*9 oxygen per cent. November 3. — Air in the town, barometer 28*76, thermo- meter 46°, rainy, with S.W. wind. Average of ten experi- ments gave 20*6 oxygen per cent. Air from the Summit of Snowdon, 3570 feet above the sea, taken by John Blackwall, Esq., May 14, 1826, at 7 p.m. ; wind N.E. light, barometer 26*20, thermometer 42°. May 28. — Average often experiments gave 20*65 per cent, oxygen. Country air three miles from Manchester, analysed the same day, average of six experiments gave 20*8 per cent, oxygen. Again, Snowdon air in six experiments gave 20*66 oxygen per cent. ; but the bottle being now half full of water, I did not examine the rest. Another bottle of air was taken at the summit on another occasion, May 18, by the same gentleman ; wind S.W., light. and on the Sulphurets of Lime. 403 May 25. — Analysed ; average of six experiments gave 20*59 oxygen per cent. Country air near Manchester at same time gave average 20*7 per cent. A second bottle of air from Snowdon, taken at the same time, May 18, gave on an average of four experiments 20*9 oxygen per cent. Air from the town at the same time, on an average of five experiments, gave 21*04« oxygen percent. 1826, July, Air from the Summit of Helvellyn. Average often experiments gave 20*63 oxygen per cent. Average of the town air found at same time was 20*73 oxy- gen per cent. Air taken in an Aerial Voyage over Cheshire. Mr. Grafton was so good as to procure me a bottle of air taken in an aerial voyage over Cheshire with Mr. Green, June 26, 1827; height 9600 feet above the sea*. The air was transferred into two phials. First Phial. June 27. — Average of seven experiments of~\ 20*7 oxygen balloon air gave . . . # . J per cent. Average of seven experiments \ n^.o© on town air gave j July 2. — Average of eight experiments of \ o/^.o. balloon air gave j ' Average of eight experiments on 1 -^ town air gave j The second phial of balloon air was carefully preserved, the phial being filled and having a ground stopper. It was analysed. 1828, May 28. — Average of three experi- \20*70 oxygen ments balloon air gave j per cent. Average of three experi- I oo.ftn ments town air gave J ^ Aug. 5. — Average of thirteen experi- ] ments, being the whole > 20*52 of the balloon air, gave J * Height found as under : Capacity of bottle 10*47 ounces. On drawing the cork under water there entered 2*77 ounces. Left 7' 7 ounces of air. Also height of barometer and thermometer below given. i The whole air in the first phial was spent in these fifteen experiments. The deterioration of the air in the first phial, by being kept half full of trough water for five days, is remarkable. 2 N2 404 Dr. Dalton on the Constitution of the Atmosphere, Average of thirteen experi- 1 20*92 oxygen ments on town air, gave j per cent. On the last-mentioned day I received a bottle of air from the summit of Snowdon through the care and attention of my friend and pupil Mr. John Hall. It was corked and well sealed with wax ; when opened under water a due portion of that fluid entered. The average of the first two experiments gave 20*44 oxy- gen per cent. The rest of the air after these two experiments was divided into two portions, and entered into two phials for examination. These were analysed a week or two afterwards. Average of five experiments with first phial gave 20*25 oxygen per cent. Average of four experiments, which emptied the first phial, gave 19*98 oxygen per cent. Average of seven experiments of second phial gave 20*3 oxygen per cent. ; and a considerable portion was left. Average of the town air was during these experiments nearly 2 1 oxygen per cent. I am not aware of any cause why this air was so much in- ferior in oxygen to that on former occasions. 1831, July 4. — Helvellyn air brought down from the summit by me; wind S.W., with rain and fog. 1. July 21. — Mixed two ounce measures of this air with one of hydrogen, so as to make six separate and successive explosions ; the hydrogen had ^^ths of a grain measure per cent, of oxygen, and this is allowed for in the corrected results. These results on the average gave 20*57 oxygen per cent. ; the highest was 20*68, and the lowest was 20*43. The residues of the six explosions were collected, and found to have 5 per cent, of hydrogen and 1 in 120 of oxygen. 2. Mixed equal volumes of this Helvellyn air and the same bottle of hydrogen used above, and fired the mixture in suc- cessive portions. The average of six experiments gave 20*8 per cent, of oxygen. No oxygen was found in the residue. By comparing the results of 1 and 2, it would seem that more oxygen is reduced from common air by firing equal volumes of common air and hydrogen than by firing one volume of common air with half a volume of hydrogen. August 23. — Mixed 100 measures of town air and 120 of new pure hydrogen; this fired gave 21*5 oxygen per cent.; there was no oxygen in the residue. This would seem to point out ^J^th of oxygen in the hydrogen, yet nitrous gas scarcely manifested so much. and on the Sulphurets of Lime, 405 1832, July 26. — Mr. Green, jiin., and Mr. John Taylor of the Manchester gas works, ascended in a balloon from Man- chester after 6 p.m., a fine, clear, calm evening, barometer being 30 inches, thermometer 65°; the balloon took a south direction, and landed in Cheshire about fourteen miles off. Mr. Taylor took a bottle of air when at the highest elevation, when the barometer stood at 16'8 inches, thermometer 55° \ whence the altitude must have been about 15,000 feet. Capacity of the bottle = 2406 grains of water. On opening it under water in temp. 64° there entered 884 grains of water. The air was soon after its reception on the 27th transferred into two small phials for examination. The first phial was mixed with 60 per cent, of hydrogen, and fired in five portions; it yielded 20*59 oxygen per cent. The second phial, mixed in like proportion, gave 20*65 oxygen per cent. Air from the town the next day, fired with the same phial of hydrogen as the preceding, gave 20*95 on the average of fi\Q experiments. Air from Switzerland, &c. In the autumn of 1835 I was favoured with three samples of air taken in elevated situations in Switzerland by my friend W. D. Crewdson, jun. Esq., of Kendal. Each of these was taken in a two-ounce phial by pouring out the contained water and corking the phial immediately, leaving only a drop or two of water within. The cork was then well closed with sealing-wax. No. 1 was taken on the Mer de Glace, August 21, estimated at the height of 6000 feet above the sea ; the second on the pass of the Simplon, August 29, at the height of 6174 feet above the sea; and the third on the Wengern Alp on the 15th September, at the height of 6230 feet. These airs were analysed in October with the following results. Oxygen per cent. Mer de Glace. — Average of four first experiments 20*2 Average of four last experiments 19*4 Simplon.— Average of four first experiments 19*98 Average of four last experiments 19*53 Wengern Alp. — Average of four first experiments 20*45 Average of four last experiments 20*11 It may not be amiss to subjoin a few experiments on air in close chambers, where a number of people have been congre- gated for two hours, the air being taken at the moment of breaking up. 1802, March 6.— Got a 20-ounce phial filled at the close 406 Mr. Brooke and Mr. R. Phillips ofi an apparent of a congregation of 500 people assembled for two hours with 50 candles burning; the air completely neutralized 150 grains of lime water, but took very little more ; this accords nearly with 1 per cent, of carbonic acid gas. The oxygen was not examined. 1824, November 28. — Examined the air at the close of an ordinary congregation, perhaps 200 people, retained for two hours. Average of five experiments gave the oxygen 20*42 per cent. 1826, March 16. — Examined the air from a crowded con- gregation after two hours' confinement, but some doors open. Average of four experiments gave the oxygen 20*23 per cent. There was a very slight appearance of carbonic acid each time a charge was passed up through lime water, a phaeno- menon never observed in ordinary atmospheric air. The general conclusions, it seems to me, to be drawn from these experiments are, that the proportion of oxygen to azote in the atmosphere on the surface of the earth is not precisely the same at all places and times ; and that in elevated regions the proportion of oxygen to azote is somewhat less than at the surface of the earth, but not nearly so much so as the theory of mixed gases would require ; and that the reason for this last must be found in the incessant agitation in the at- mosphere from winds and other causes. June 6, 1837. LXVI. Note 071 an apparent Case of Isomorphous Substitution, By H. J. Brooke, Esq,, F.R.S. To Richard Phillips, Esq., F.RS, My dear Sir, T SOME time since pointed out the very near identity of *- the forms, cleavage, and angular measurements of zoizite and euclase, but I omitted to refer to their apparently ana- logous chemical composition. Silica. Alumina. ' Lime. Glucina. Protoxide. Zoizite (Klaproth) 43 , 29 , 21 , 3 Euclase (Berzelius) 43-22, 3056, 2178 222 This is apparently a case of isomorphous substitution, but on pointing it out lately to a chemical friend he observed, that the proportion of glucina in euclase was 2 atoms, while the lime in zoizite was only 1 atom, and that the identity of form must therefore be accidental ; but if this be so, may not all other cases of isomorphous substitution ( I do not allude to Case of Isomorphous Substitution. 407 plesiomorphous binary compounds) be equally accidental, or rather are not all these governed by some other at present unknown law ? Can you throw any light upon this difficult subject. Yours truly, H. J. Brooke. LXVII. Observations on Isomorphism^ in reference to the precedi?ig Communication by Mr. Brooke. By R. Phillips, F,n.S, L, 4" Ed. /^N comparing the analyses of zoiziteand euclase quoted in ^^ Mr. Brooke's letter, it is evident that substituting glucina for lime, these minerals may be considered as similar ; but whether this be a case of isomorphous substitution I now propose to inquire. Professor Johnston ( Report of British Association, vol. i. p. 423) states that " binary compounds which replace each other contain not only the same absolute number of atoms, but also the atoms of the two elements in the same relative proportion." According to Berzelius the equivalent of lime is 28*53, and the (double) equivalent of glucina is 77*13; then 28-53 : 21 : : 77*13 : 56*77, the quantity of glucina which on this supposition should replace 21 of lime: if we take the single equivalent of glucina the quantity of it contained in euclase would, of course, be 28*38 ; but the actual quantity is only 21*78, or about three fourths of what it should be, on the supposition most favourable to the doctrine of isomorphism. But another difficulty presents itself in considering lime and glucina as isomorphous ; Prof. Johnston observes, in the paper above quoted, " if in peroxide of iron the iron is to the oxygen in the atomic ratio of two to three, the atoms of alu- minum and oxygen must in alumina have the same ratio, or both bases must be sesquioxides." Similar reasoning will, I presume, apply to other oxides which are supposed to be iso- morphous ; now, according to Berzelius, lime is a protoxide, while glucina is a sesquioxide; these substances, therefore, cannot be isomorphous. There is however every reason to believe that this, and indeed any difficulty whicB is presented to the doctrine of isomorphism, will be readily overcome, when we observe the liberties which the expounders of it take with what appear to be the best established facts. In the Records of Science (vol. iii. p. 433) there is a paper by Professor Clark, in which, on account of " a difficulty in isomorphism," he has proposed to double the atomic weights of certain substances. Addressing Professor Mitscheriich, Professor Clark states : it08 Mr. R. Phillips's Observations " Now the discrepancy I have alluded to is this : The waterless sulphate of soda . . Na S and of course, the isomorphous salts Ag S, Na Se, Ag Se, you found to be of like form, Not with manganate of barytes . . . Ba Mn But with oxymanganate of barytes . . Ba Mn Mn. " This discrepancy, which, occurring iii such a case, appeared to me very startling on the first perusal of your paper, I pro- pose to show, may be removed, by regarding the salts in ques- tion, as we may reasonably do, notwithstanding our precon- ceived notions to the contrary, to be as much alike in constitu- tion as you have proved them to be in form." After some further observations Professor Clark proceeds : ** While abiding by this your doctrine, and proceeding on a like principle to what has just now been illustrated in the case of the oxymanganate and the oxychlorate of potash, it is possible, I conceive, to remove that unlikeness of constitution, so apparent in the following salts of like form : The oxymanganate of barytes . . . Ba Mn Mn The waterless sulphate of soda . . Na S These two salts we may better compare, unswayed by any theory, by regarding them in their ultimate components, thus: Ba Mn Mn = Ba -f 80 + 2Mn NaS =Na + 40 + S But as manganese is isomorphous with sulphur, we can, better still, compare the two salts by taking the ultimate com- ponents of two atoms of sulphate of soda, thus : Ba Mn Mn = Ba + 8 O + 2 Mn oxymanganate of barytes. 2 Na S = 2Na4-804-2S sulphate of soda. Instead whereof I suggest, ^ So+ 80 + 2S" (where So stands for the atom of sodium, being in weight double the received atom, which is represented by Na.) " Comparing together, as we here do, so much of each of the salts as contains eight atoms of oxygen, we find two atoms of manganese substituted, without affecting the form of the com- pound, by two atoms of sulphur." This proposal, as Professor Clark says of the difficulty 071 Isomorphism, 409 which it is intended to overcome is "very startling"; but this is not all, for a theory still more destructive of what has been considered as settled is propounded by the Professor, in order that one difficulty in isomorphism may be got over, where so many exist. After other hypothetical observations Professor Clark ob- serves, " But partiality is unlike a law of nature, and indeed the partiality disappears when we regard the oxygen salts as having metals and not oxides for their bases." " According to this view, when oil of vitriol, regarded as an hydrogen acid (H 2S) acts on an oxide, it is not a simple combination that takes place, but a double decomposition, resulting in a neutral salt and water, precisely as takes place when hydrochloric acid acts on oxides;" and the Professor adds, " if observation, which must be the final arbiter, shall determine one coinci- dence more to accord with the doubled atoms of sodium and silver, then, for aught I can see, the doctrine of oxygen salts having oxides for their bases must be at once abandoned." Thus then because two salts are isomorphous which ought not so to be, according to the received atomic weights of certain bodies, these are not only to be altered, but we are on the brink of losing altogether the numerous class of oxygen salts. It is however some consolation to observe that the cham- pions of isomorphism differ so widely in their opinions, that some chance remains of the permanence of the received doc- trines as to atomic weights and the constitution of oxygen salts. In the last Number of the Philosophical Magazine, p. 324, Prof. Johnston has published a paper, the object of which is to prove that the atomic weights of soda and silver, &c., in- stead of being doubled to reconcile certain isomorphous dis- crepancies, ought to be halved for the same cause. In other words, the opinions of the Professors are as 4 to 1, on a sub- ject in which though fancy has much to perform, observation and facts ought to decide. Professor Johnston observes, " The isomorphism of two compounds generally implies an analogy in their atomic con- stitution,—that they are both sulphurets of the same order. If the compound of copper be a disulphuret Cu, that of silver is most probably a disulphuret Ag, and if so the atomic weight of silver must be reduced one half, or to 6*75. We have there- fore an argument in favour of the old result of Dulong and Petit." This however is not all ; " the introduction of this change, however," continues Professor Johnston, " would render ne- 410 Mr. R. Phillips's Ohse^'vations cessary a like change in the received atomic weight of sodium, with the oxide of which in anhydrous sulphate of soda (The- nardite) that of silver in sulphate of silver is isomorphous. Soda, common salt, and sulphuret of sodium must be repre- sented Na, NaCl, Na N." " Nor," says Professor Johnston, " can the change stop here." Indeed I wish he could point out where it will. " Several years," he continues, "have elapsed" since Mitscherlich announced the very interesting fact, that the nitrates of potash and soda were isomorphous respectively with arragonite and calc spar, and that they presented the same cleavages (Pogg., ^w.,xviii. p. 173) ; to which Marx afterwards added that the rhomboids of nitrate of soda possessed the doubly refracting structure in a higher degree even than calc spar. {Jahrhuch der Chim, und P/ii/s.,xix. p. 166.) From these obser- vations it was natural to infer that some relation existed be- tween the two alkaline nitrates analogous to the relation be- tween the two forms of carbonate of lime ; that like carbonate of lime the nitrates of potash and soda might each be capable of assuming two forms isomorphous each with each, though in ordinary circumstances of temperature, &c. the form pre- ferred by each did not correspond ; the nitrate of potash ge- nerally affecting the right rhombic prism, the nitrate of soda the rhomboidal form. The probability of such a relation was strengthened by a comparison of the analysis of chabasie from different localities and by different chemists, from which there appeared strong reason for believing that potash and soda were capable of replacing each other in equivalent proportions." I wish Professor Johnston had favoured us with the ana- lyses from which he has arrived at the fore-mentioned conclu- sion. I have copied all I can find ; they amount to seven. *1. 2. 3. 4. 5. 6. 7. Silica 43-33 50-65 49'17 4907 48756 48-988 46184 Alumina .... 22-66 17-00 18-90 18-90 17'440 19774 18-423 Lime 3*34 9-73 10-463 4-068 7029 Potash 9-34 1-70 ... 1219 1-458 Soda 12-19 6-066 5967 Oxide of iron ... 0404 0397 Water 21- 19-50 19-73 19-73 21720 20-700 22- 99-67 . 98-58 : 99-99 : 9989 : 99842 . 100- 100- I confess I am entirely at a loss to conjecture on what prin- ciple Professor Johnston finds " strong reason" for believing, • 1. Vauquelin. 4. Arfwedson. 7. Lehunt. 2. Berzelius. 5. Dr. Thomson. 3. Ditto. 6. Lehunt. on Isomorphism. 411 upon the evidence of these analyses, that potash and soda are capable of replacing each other in equivalent proportions ; but I admit there is abundant evidence to prove that they replace each other in proportions which are quite indefinite. The only results which are at all favourable to Professor Johnston's position, are those of Vauquelin and Lehunt; in these I admit that the potash is to the soda nearly as 3 to 2, which are proportional to their atomic weights ; but in one of Lehunt's analyses the quantity of lime is more than twice as great as that in Vauquelin's. According to Berzelius the potash in one specimen amounts to 1*7, and the soda in the other to 12*19 ; according there- fore to the rule which I have admitted, the soda should be only frds the weight of the potash, or 1*12 instead of 12*19; so that here we have one equivalent of potash isomorphized by about 10 equivalents of soda. This is quite at variance with the rule which I have quoted from Professor Johnston, viz. " that binary compounds which replace each other, con- tain not only the same absolute number of atoms, but also the atoms of the two elements in the same relative proportion." After alluding to an anomaly formerly presented by the alums, but now supposed to be explained, respecting the isomorphism of potash and soda. Professor Johnston continues : "But all doubt has at length been removed from the relation between the forms of potash and soda by a beautiful observation of Frankenheim (Pogg., xi. p. 447). He has found that when a saturated solution of pure nitrate of potash is left in small quantity to spontaneous evaporation, two sets of crystals are formed, one in prisms, the other in rhomboids ; the former the common arragonitic form generally assumed by nitrate of potash, the latter that of calc spar, commonly assumed by soda. The rhomboidal crystals are microscopic and pass into the prismatic form by friction, by pressure, or by contact with a prismatic crystal, and hence when the salt is crystallized in large masses they entirely disappear. It may therefore be considered as demonstrated that the nitrates of potash and soda are at once isomorphous and dimorphous, or isodimor- phous ; and since the potash and soda replace each other in certain mineral compounds (chabasie for example) the alkalies also, perhaps the metallic radicals themselves, may be consi- dered isodimorphous." I know not whether in the original paper cited by Professor Johnston it is stated that the " microscopic" crystals were sub- mitted to measurement; if not I confess that I am not ready to admit the case as proved, for it might be easy to confound " microscopic" rhomboids and shortened prismatic crystals. Professor Johnston, in alluding to the researches of Dulong 412 Mr. T. Taylor's Observations on Urinary Calculi and Petit into the specific heats of metals, observes that they have rendered it extremely probable that the atoms or equi- valents of these elementary bodies have the same specific heat; and that the usually received atomic weights of silver, gold, and mercury should be halved. The table in which this comparison is exhibited contains sulphur and 13 metals; and with respect to it the late Dr. Turner remarks, " It will be observed on inspecting the last column of the table, that the product of the specific heat into the atomic weight is very nearly 3 for the first eight substances. Platinum de- viates visibly from the law, and bismuth and cobalt strikingly. The three last metals (mercury, silver and gold) would nearly coincide with the law, were their respective atomic weight estimated at half the number given in the table." Waiving the objections which Dr. Dalton has made to the results of these experiments, it is, I think, requiring too much to ask chemists to reduce the atomic weights of three metals to one half, when of 3 others one deviates visibly and two strikingly from the law. The difficulty with respect to mercury, gold, and silver may, however, I think, be got over in a way which I wonder did not suggest itself to Professor Johnston. If heat com- bines with bodies in definite proportions, it may in some cases like other elements combine in double proportions ; instead therefore of halving the equivalents of these metals, let us suppose that they are combined with two equivalents of heat, and the revolution of atoms with which we are threatened will be rescued from this source of discrepancy. It is an old observation that when things get to the worst they will mend ; I hope therefore that two more Professors may attempt to remove the difficulties of isomorphism, one by multiplying the received atomic weights by 19, or any equally convenient number, and the other by dividing them by the same. LXVIII. Observations on Urinary Calculi, with a Descriptive Account of the Collection in the Museum of St. BartholomeisS s Hospital. By Thomas Taylor, Esq., M.R.C.S. To the Editors of the Philosophical Magazine and Journal, Gentlemen, IITAVING completed the examination of the valuable col- ■■--*- lection of urinary calculi, of which the specimens of cystic oxide described in your April Number, p. 337, form a part, may I request the insertion of the following observations, should you deem them of sufficient interest to merit a place in the Museum of Si, Bartholomeia^s Hospital. 4 1 JJ in your pages? The entire collection consists of 129 speci- mens, of which about one third were unexamined ; the com- position of the others had been pointed out some few years ago by Dr. Hue. It was however necessary to re-examine many of these, as from their not having been divided their internal structure had not been described. In this as in most other collections chemical composition has been taken as the basis of arrangement. This plan would be sufficiently simple and accurate if calculi were always homogeneous, but as by far the greater number consist of layers differing in composition, some additional method is necessary. In the present instance the alternating calculi have been classed according to the number of layers which are present, and these are subdivided with reference to the composition of the nucleus. I am aware that many objections might be urged against this method, and it would no doubt have been more scientific to have grouped together all those in which the layers observe a similar order of succession ; but it was found that such an arrangement would have introduced so many subdivisions as completely to destroy that simplicity which in a museum continually subject to increase it was necessary to preserve. The following table exhibits the relative frequency of each species, together with the order of succession of the' layers in the alternating calculi. Uric acid, nearly pure 11. Urate of ammonia intimately mixed with variable ) proportions of oxalate of lime and the phosphates J Oxalate of lime nearly pure 8. Phosphate of lime 4t. Phosphate of ammonia and magnesia 1. Mixed phosphates 1 10. Ditto deposited on foreign bodies J 3. Cystic oxide 2. Alternating Calculi. Uric acid : Urate of ammonia 4. Oxalate of lime 3. Phosphates 6. Urate of ammonia : Uric acid 2. Oxalate of lime ... 7. Phosphates 13. Oxalate of lime : Uric acid 3. ■ Urate of ammonia 1. • Phosphates ... 13. 8. 414? Mr. T. Taylor's Observations on Urinary Calculi Uric acid; Urate of ammonia : Phosphates ... 3. Ditto Oxalate of lime : Ditto l. Urate of ammonia : Uric acid: Phosphates ... l. — Oxalate of lime: Ditto ... 13. Ditto Uric acid ... 1. ' Urate of ammonia 1. Oxalate of lime : Uric acid: Ditto l. ■ Oxalate of lime 1. Calculi consisting of several layers 8. Uric Acid. — Of these calculi, the greater number has been taken from adults; the finest specimen, which is remarkably compact and crystalline, was extracted by Mr. Lawrence from the bladder of a man aged 72: some few contain a little urate of ammonia, and in these a minute quantity of oxalate and phosphate of lime may be detected. Urate of Ammonia. — In no table that has been given by writers on this subject has urate of ammonia been regarded as forming an independent concretion, and its existence as such has been much disputed. This difference in opinion has arisen from the difficulty of separating this salt, in an unex- ceptionable manner, from the triple phosphate with which it is frequently mixed. The chief chemical evidence adduced in favour of its pre- sence, is the evolution of ammonia when these calculi are treated with a solution of caustic potash. It has been con- tended, on the other hand, that the ammonia is derived from the decomposition of the phosphate of ammonia and magnesia, or of urea accidentally present. When the former is the case I am not aware of any method by which this objection can be set aside, for every plan which I have hitherto tried of separating these salts so as to avoid their reaction on each other has failed. There are, however, many calculi in which the presence of urate of ammonia can be satisfactorily shown, and which con- tain none of the triple phosphate, or which contain it in so small a quantity as to be inadequate to account for the quantity of ammonia combined with the uric acid; and as these calculi possess the same external appearances, and in their general chemical characters correspond exactly with those containing the phosphate of ammonia and magnesia, I think it fair to infer that their composition is similar. Notwithstanding there- fore the deservedly high authorities by which the contrary opinion has been maintained, I must fully concur in the ob- servation of Dr. Prout, that all those calculi which present when broken an amorphous and earthy-looking fracture, con- ill the Museum of St, Bartholomew's Hospital, 415 sist essentially of urate of ammonia. That the ammonia in these calculi is combined with uric acid may be shown in the following manner. Let a small quantity of boiling water be poured over a few grains of the calculus placed in a small paper filter ; the solution will on cooling deposit a copious flocculent white precipitate of urate of ammonia, which from its appearance alone^ may be easily distinguished from the scanty crystalline precipitate which takes place when uric acid calculi are similarly treated: should too much water have been added, it will be necessary to evaporate the solution a little before precipitation of the urate of ammonia will take place. Free uric acid is very frequently present in these calculi, and may be observed in the form of minute crystals mixed with the amorphous precipitate of urate of ammonia, or adhering to the sides of the vessel ; when however the triple phosphate is present this test is of no value, for the mere affusion of hot water over a mixture of pure uric acid and phosphate of ammonia and magnesia will give rise to the formation of urate of ammonia, and thus vitiate the result. This fact appears to add considerable weight to the opinion of Dr. Prout, that uric acid is seldom or ever deposited in a free state together with the phosphates. There is another distinctive character by which these calculi may always be recognised, viz. their decrepitating on the application of heat: in no well-marked specimen has this property been wanting, and I consider it as perfectly characteristic of the species. To what this peculiarity is owing it is not easy to determine, for pure urate of ammonia does not decrepitate when heated. It has been generally referred to the small quantity of oxalate of lime contained in these calculi ; but this is hardly probable, as oxalate of lime calculi undergo combustion silently, and the same property is possessed by those specimens in which the phosphates form the predominating admixture. It may possibly arise from the sudden extrication of ammonia, and its degree of force depend upon the compactness of the body, for in those calculi which from the predominance of the earthy phosphates are porous and friable, this property is considerably impaired or altogether lost. As far as my observation has gone the urate of ammonia in these calculi is never in a state of purity, all of them containing variable quantities of oxalate of lime, the phosphates, uric acid, and in some few instances urate of lime. The quantity of earthy matter however in the compact varieties is very small, seldom exceeding a few parts per cent. 15 grs. of a specimen which was rather disposed to crumble, 416 Mr. T. Taylor's Observations on Urinary Calculi and in which the characters of urate of ammonia began to pass into those of the phosphates, gave on analysis: Uric acid 9*1 Phosphate of lime 1*5 Phosphate of ammonia and magnesia 3*1 Animal matter, ammonia, and loss ... 1*3 15-0 The ash which is left when these calculi are burnt is almost always alkaline and infusible: in three cases only were the phosphates present in such proportions as to render it fusible. By reference to the table it will be seen that urate of ammonia, so far from being rare, as is generally stated, forms in the pre- sent collection the most frequent primary deposit; as out of 82 calculi which have been divided, the proportion as to nuclei is as follows: uric acid 18, urate of ammonia 41, oxalate of lime 23 ; and in those which are homogeneous the proportion of urate of ammonia though less is still very considerable. It has been remarked by Dr. Prout, that this species of calculus generally occurs in children, and the accuracy of this obser- vation is fully borne out by the histories attached to these calculi ; for although unfortunately they are not so perfect as to enable me to institute a strict comparison of the relative frequency of each variety at the different periods of age, yet in the present case by far the greater number are expressly stated to have been taken from persons under puberty. Phosphate of Lime. — Under this head are arranged some small calculi from the prostate gland, and three large irregu- lar concretions from the kidney ; two of these contained car- bonate of lime and some urate of ammonia, the latter being apparently in separate layers. In one a small quantity of the phosphate of ammonia and magnesia was likewise present. Whether the phosphate of lime in these calculi was primarily secreted, or merely coated a nucleus of some other substance, is uncertain, as on account of their figure it was not considered advisable to divide them. The other specimen was examined by Dr. Hue, and consisted of phosphate of lime with a large quantity of animal matter. The term bone earth which is frequently applied to these calculi is faulty, as it conveys the idea that the lime and phos- phoric acid are in the same relative proportions as in the earthy matter of bones ; whereas it has been shown by Dr. Wollaston that the calculi from the prostate gland contain a much larger proportion of acid, forming what is usually termed the neutral phosphate, or more correctly speaking the diphos- in the Museum of St, Bartkoiomew's Hospital, 417 phate. From several facts which I have observed, I am, 'how- ever, convinced that the relative proportions of a^id and base in the phosphate of hme surrounding other calcuh*, whether alone or mixed with the phosphate of ammonia and magnesia, varies considerably : and whether this arises from a mixture of two or more of the already known com- pounds of lime and phosphoric acid, or whether they are definite compounds of which we have at present no know- ledge, I am unable to decide, although I believe the latter may occasionally be the case. In a calculus which consisted of urate of ammonia and oxalate of lime surrounded by the mixed phosphate, was observed among the latter a layer which had an imperfectly fibrous structure and was much harder in texture and more compact than the rest : on di- gesting a portion of this in dilute acetic acid effervescence took place and some lime was dissolved ; the insoluble matter left had a crystalline appearance, and was found to be phos- phate of lime. When dissolved in stronger acid and the so- lution neutralized by ammonia a gelatinous precipitate fell, which after standing about four and twenty hours was wholly converted into a number of small crystals, having undergone similar changes to freshly precipitated uric acid. If these crystals are left for a few days in the solution from which they have been thrown down, they gradually disappear, and are reconverted into an amorphous precipitate, differing only from the former in not being quite so gelatinous. The nature of the changes which take place I am unable at present to explain, although 1 find that when the diphosphate of lime (prepared by dropping a solution of phosphate of soda into one of mu- riate of lime, the latter being in excess,) is precipitated from its acetic solution, the same appearances present themselves : the conversion is, however, only partial. The calculi which contain this phosphate usually partake more or less of the external characters before mentioned ; in some of them it ap- peared to be mixed with the bone-earth phosphate, properly so called. If it be identical in composition with the diphos- phate, which I believe to be the case, the property alluded to is not noticed in any of the chemical works I have consulted. I am informed by Dr. Prout, that he has remarked the same. Only in one instance have I seen the radiated structure noticed by Dr. Wollaston ; it formed a thin layer among the mixed phosphates, surrounding a calculus of oxalate of lime. Phosphate of Magnesia and Ammonia. — This specimen has not been divided; it probably contains a nucleus of uric acid, and should therefore have been arranged among the alter- nating calculi. PhiLMag. 5.3. Vol. 12. No. 76. Mai/ 1838. 5i O 418 Mr. T. Taylor's Observatio?is on Urinajy Calculi Mixed Phosphates, —The calculi arranged under this divi- sion are composed throughout of the phosphate of lime and phosphate of magnesia and ammonia mixed in variable pro- portions. Some of these contain thin layers of urate of am- monia, and this salt is frequently present in the fusible cal- culus. The number of calculi of this description is rather above the usual average, as the phosphates seldom form the primary deposit. It is probable that some of these calculi were formed by the decomposition of urine, which from some cause or other could not escape from the bladder ; such appears to have been the case in two of these specimen?; ; one having been extracted by Mr. Stanley, from a cyst which communicated with a fis- tulous passage leading from the bladder to the perinaeum; and the other having occurred in a patient in whom, on account of an enlarged prostate gland, lithotomy had been performed above the pubes, and through which opening the urine was subsequently expelled. Cystic Oxide. — Of these calculi a full description has been given in the Phil. Mag. for April. Carbonate of Lime. — This salt rarely forms the principal constituent in calculi from the human subject, and no speci- men of the kind exists in the museum ; it is however very frequently present in small quantities, and generally mixed with the phosphates. Purpurate of Ammonia, — Of this singular substance it is not easy to obtain decisive chemical evidence, partly on account of the small quantities in which it occurs, and partly on that of the facility with which it undergoes changes by which its colour is destroyed. I believe I am correct, however, in stating that I have detected it in three instances. In one it formed flesh-coloured layers alternating with the phosphates, in the others it merely coated the calculus. In all of them it was mixed with urate of ammonia. With regard to the alternating calculi the table that has been given expresses nearly all that is worthy of particular notice. It may be observed that in no one instance have the phos- phates either pure or in a state of mixture formed the nu- cleus ; indeed this circumstance is so extremely rare, that it has been laid down as a general law by the highest authority on the subject, " that a decided deposition of the mixed phos- phates is not followed by other depositions." There is, how- ever, one specimen in the museum which must be regarded as presenting an exception to this statement. The calculus in question consists at its centre of urate of in the Museum of St, Bartholomew's Hospital, 4-19 ammonia containing a little oxalate of lime, around this is oxalate of lime nearly pure, a white layer three eighths of an inch in thickness follows, and is followed by a thin stratum of oxalate of lime of a very dark colour; upon this is deposited crystalline uric acid marked with the irregular concentric lines peculiar to oxalate of lime calculi, although it contains but a mere trace of that substance : the whole was coated by urate of ammonia, uric acid, and oxalate of lime irregularly deposited. As in the museum catalogue the white layer was merely described as fusible, and as Dr. Prout (to whom, with the permission of Mr. Stanley, I had the pleasure of showing this specimen,) suggested that it might contain urate of soda, it was carefully examined for that substance, and the result was, that in addition to the mixed phosphates with some carbonate of lime, a small quantity of uric acid and soda was present. The quantity of the latter was, however, very minute; oxalate of lime could not be detected. It is highly probable that in this case the deposition of the phosphates had been caused by the use of alkaline remedies, and that on the discontinuance of these, the former diathesis had returned. If this were the case it can hardly be consi- dered as a fair exception to the law above mentioned. By most writers on this subject, a species of calculus has been noticed, consisting of the different ingredients mixed in- discriminately together, from which circumstance it has been termed mixed or compound. The only specimens which ap- pear to me to deserve this appellation are the mixed phos- phates and the less pure varieties of urate of ammonia. As however there is no calculus which is absolutely pure, and it would be exceedingly difficult to decide what proportion of the dissimilar ingredients should constitute a mixed calculus, this class has not been included in the arrangement. I may, however, remark that with the exception of those layers which occasionally intervene between two different deposits, and which, as has been remarked by Dr. Prout, usually consist of a mixture of the old and new layers, only two specimens have come under my notice at all approximating to the so-called mixed calculus, or in which the slightest hesitation occurred in assigning their proper place : of one of these I have given the analysis under the head of urate of ammonia: the other con- tained a much larger relative proportion of the mixed phos- phates and surrounded a nucleus of uric acid, it was therefore arranged among the alternating calculi. Although in the foregoing observations I have endeavoured to conhne myself to points of general interest or on which a difference of opinion existed, yet I am afraid they have already extended to too great a length, and 1 shall therefore no longer intrude 2 C) 2 420 Messrs. Daniel and Robert Cooper 07i'the upon your notice, merely requesting their insertion at your earliest convenience. I am, Gentlemen, yours, &c. New Bridge Street, April 13, 1838. Thomas Taylor, M.R.C.S, LXIX. On the Luminosity of the Human Subject after Death, with Rema7'ks and Details of Experiments made with a view of determining the nature of the fact. By Mr, Daniel Cooper, A,L.S., Curator to the Botanical Society of London, Sfc, and Mr, Robert Cooper.* /^N the 14.th day of February, 1838, the body of William ^^ Tomkins, aged 88, shoemaker by trade, was received at the Webb-street School of Anatomy and Medicine, Borough, having died of age and debility ; and on the 3rd of March that of Robert Boreham, aged 45, was also received with the fol- lowing history. It appeared that this individual, previous to his death, had been observed in the street in a state of ex- treme poverty, and was accordingly conveyed by a police officer on duty to the Station House, where, from extreme fatigue and exhaustion, the man died on the 26th of February. Being an unclaimed corpse, the parish authorities (according to the regulations of the Act of Parliament for supplying the Anatomical Schools with subjects for dissection) sent it to Webb-street. Previous to the reception of the latter, nearly the whole of the first subject had been dissected, and the only part which exhibited the luminous property was the left leg, which had been removed, according to custom, at the upper third of the thigh. Not having been informed of this phagno- menon until it had been despatched for interment, we had not the opportunity of making experiments with regard to the cause. We were, however, more fortunate with the latter subject, which presented the same appearance, but in a greater degree. Upon examination it was evident that the man had been a muscular and likewise a hard-working individual, if we might be allowed to judge from the appearance of the skin of the palms of the hands. The phaenomenon was first observed by Mr. J. Appleton, (the Curator to the above establishment,) on Saturday the 3rd March, upon taking his accustomed round of an evening to every part of the building previous to retiring to rest. He was greatly surprised at perceiving the extremity before men- tioned to be luminous ; never having heard or witnessed in the whole course of his experience, commencing in 1812, a similar occurrence. * Communicated by the Authors : see the Intelligence and Miscellaneous Articles in a future page. Luminosity of the Human Subject after Death, 4<^1 A few nights after the introduction of Boreham, Mr. Ap- pleton observed this subject to be similarly affected, and the following morning communicated this fact to the Professors of the School. The circumstance having become generally known to the Pupils, several assembled the next evening for the purpose of observing this singular and novel phaenomenon, when it was remarked by Mr. Appleton that the luminosity had considerably increased since its first appearance. This novel fact we consider deserving the attention of phy- siologists, for in no work can we find recorded any notice of the phosphorescent or luminous appearance of the human subject. We are fully aware of its occurrence in many of the lower and even the higher classes of animals ; but we are not aware of the present fact having been heretofore recorded. Development of Light in the Lower Animals, and certain Substances, — Miiller, the celebrated German physiologist, in a late edition of his work on the Elements of Physiology, (translated by W.Baly)makessome observations with respect to animals&c, which possess the power of emitting a phosphorescent light. The following is but a brief abstract from the work. Miiller commences with a description of the animals which produce the phosphorescence of the sea, and enumerates some of the Infusoria, Polipifera, Medusce, Annelides, Planarice, and Mol- lusca, mentioning occasionally some of the leading genera in each group. He then notices some of the leading phospho- rescent crustaceans and insects, and mentions the opinion of Treviranus with respect to the light emitted from insects, viz. that the internal parts of generation are the source of light. He then further alludes to the opinion of Treviranus, viz. that light is derived from matter containing phosphorus, which is formed under the influence of light, but once formed is in some measure independent of light. He then brings forward the opinion of Carradori, Beccaria, and Monti as to the power of certain bodies of absorbing light during the day and emitting it during the evening, as is evidenced by several mineral sub- stances, such as sulphate of barytes mixed with sulphuret of barium, oyster shells heated to redness with sulphur, &c., and also by several organic substances when dried, such as seeds, flour, starch, acacia gum, quills, cheese, yolk of egg, muscle, tendon, isinglass, glue, and horn. We areinformed, accordingto the observations of Mr. White, that he has repeatedly witnessed the luminous appearance of birds when they have been hanging for some time. Whilst we ourselves are aware of the fact, that many animals, such as dogs, cats, &c., which have been killed, and left exposed to the atmosphere in ditches, &c. have emitted a pho^horescent 42S Messrs. Daniel and Robert Cooper on the light ; we have also been informed by Mr. Nazer that he has distinctly observed this luminous property in veal. In order further to verify the fact that it has been observed in several Mammalia, we have made diligent inquiries of several pur- veyors of meat in the metropolis, who have the opportunity of seeing meat in all its stages of decomposition, and we are in- formed, that they have at times perceived it on a dark night to be slightly luminous ; but such a phfienomenon is of rare oc- currence. The common opinion with these individuals with respect to the cause, is, that the meat had been struck by light- ning, it having been generally observed in the summer months. On the parts of the Body most affected. — When the lumino- sity was discovered in Boreham, it was observed to occupy both the interior and exterior of the thorax, and gradually ex- tended to other parts of the body, more especially the bones, tendons and fasciae, and also to the muscles, but in a slighter degree. On Saturday, March 10th, we observed the cartilages and bones of the ribs extending from the fourth to the seventh on the right side, and on the back from the fifth to the ninth dorsal near their point of attachment to their vertebrae : the light in the interior corresponded in situation to the light on the exterior of the thorax ; there was no phosphorescence ob- served on the viscera of the chest or abdomen. It likewise extended over the right and slightly over the left lumbar, sa- cral, and iliac regions as far down as the insertion of the tensor vaginae femoris between the two laminae of the fascia lata, from which fascia we were enabled to remove it with our fingers, and to them it gave a luminous appearance. On the evening of the following Monday we continued our researches. On entering the room we observed it greatly diminished in in- tensity; and upon examining the body we perceived the right knee (the integument of which had that day been removed) to be very luminous. Upon taking a scalpel and scraping the bone, we were surprised to find that the luminosity in no way diminished : although we could remove it by continual scrapings, it seemed to extend into the substance of" the bones. Power of increase, — In order to ascertain whether Boreham had been inoculated with the matter from Tomkins, we placed a portion of the luminous matter taken from the former on the chest of another subject, situated on the opposite side and further end of" the room, on Monday the 12th; and accord- ingly on Wednesday the 14th, as we anticipated, we disco- vered the trunk of the inoculated subject to be luminous to a very great extent. This occurrence clearly proves to our minds, that the matter from Tomkins had inoculated the body of Boreham. iu order to ascertain whether the luminosity Luminosity of the Human Subject after Death, 423 was situated in the moist or dry parts^ we noted in the dark the situation of the luminosity; which upon examination in the light showed it to be the moistened parts. Microscopic Observations. — With a view of elucidating this phaenomenon we submitted a portion of the luminous matter scraped carefully irom the subject to microscopic examina- tion, in the first place, with the idea that from its exceedingly rapid augmentation it was due to an animal very low in the scale of organization. Our first examination led us to suppose, from the peculiar motion of some of the molecules in the fluid, that an animal of extreme minuteness was present : but upon further examination, with the assistance of Mr. Bowerbank's microscope and experience in these matters, we were convinced that no such animal as the Monas existed in the matter. It was not until we had an opportunity of witnessing the various but similar currents in a weak solution of gamboge, that we could reconcile ourselves to the appearance ; for at times we observed small globules starting from one side to the other, and occasionally stemming the current for a considerable dis- stance. Until we had observed the similar motion in the gam- boge, we did not feel perfectly satisfied that no living being there existed. In the course of the examination, Mr. Bower- bank observed a small threadlike body dart across the field of the microscope, which he immediately recognised as one of those hoAies {Vibriones) which are so abundantly seen upon ma- cerating animal matter, such as a mouse, in water for a length of time. The power of the lens under which we observed the above was about 900 ; and speaking in general terms of the size of the molecules before mentioned, as viewed under the above power, they were as near as could be ascertained the 100, 000th of an inch in size ; so small indeed were they, that it was totally impossible to measure them with the finest micrometer as yet constructed. And according to the measurement of certain animals which among others produce the luminosity of the sea, as measured by Mr. Bowerbank at about lOOlh of an inch, these molecules, for we will not give them any higher title, were at least 1000 times smaller. Although not exactly in connection with the present subject we have given the rough estimate of the molecules observed, as compared with the minute animals which are known to give the sea the beautiful phosphorescent appearance so frequently observed. A portion of luminous matter having been placed under the microscope, the light evolved was sufficient to illuminate the field in patches. The luminosity appeared to be emitted from an oilij matter. Experiments with gases. — Having been led to suppose from 424 Messrs. Daniel and Robert Cooper on the the microscopic examinations that there were no traces of ani- mals, we resolved to repeat the experiments of Macartney and Murray, as regards the non-disappearance of the phospho- rescent light emitted from animals in the different gases. For this purpose we prepared in well-stoppered phials the follow- ing gases, viz. oxygen, hydrogen, nitrogen, chlorine, carbonic acid, carbonic oxide, sulphuretted and phosphuretted hydro- gen ; and into a phial filled with each of these gases we intro- duced a portion of luminous muscle, tendon, or fascia for the space of 4?0 minutes, and the following were the results of the experiments : — No effect observed in Slight effect produced in Total extinction in Oxygen "l remained lu- Carbonic acid. Chlorine. Hydrogen l minoiis for Sulphuretted hy- Nitrogen J five days. drogen. Carbonic oxide. Phosphuretted Hydrogen. From the above experiments, we are compelled to disagree with the conclusions of Macartney and Murray as regards the non-disappearance of the phosphorescent light emitted from animals when immersed in the different gases. By perusing the above table, it will be observed that a total extinction of the light takes place when immersed in chlorine and sulphu- retted hydrogen : this took place within the space of two minutes. Appeara?ice in vacuo. — On this point, we cannot coincide with the opinions of Macartney and Murray, having intro- duced an exceedingly luminous portion of flesh under the re- ceiver of an air pump ; and upon exhausting the vessel, the phosphorescence almost entirely disappeared, after having been in vacuo for the space of 1 5 minutes ; but upon the re- admission of the atmosphere, it immediately regained its for- mer brilliancy, which is contrary to the opinions of the above experimentalists. Upon removing the portion of flesh from the phial containing carbonic acid, and placing it beneath the receiver of the air pump, and on first exhausting, it ap- peared to regain its luminosity in a slight degree; further exhaustion however diminished it. Oxygen having been ad- mitted in the place of air, it soon regained its original bril- liancy ; this effect was in like manner produced by the admis- sion of the atmosphere as before, and also by some of the dif- ferent gases above-mentioned. Effect in condensed air. — From the result of the foregoing experiment, viz. the diminution of the brilliancy upon with- drawing the atmosphere, we were led to suppose that a con- trary effect would be produced upon condensing the air : to Luminosity of the Human Subject after Death. 425 eflPect this, we procured a Cavendish bottle, in which a por- tion of luminous matter was placed. Upon using the con- densing syringe, a visible increase of brilliancy occurred. Luminous appearance under water. — Upon taking a portion of luminous flesh, and placing it in a glass of distilled water, it retained its luminosity for the space of from 10 to 15 minutes ; and upon carefully removing the luminous matter from an- other portion of flesh with a knife, and agitating the water with the instrument, small globules of luminous matter were ob- served dispersed throughout the fluid, which remained for the space of 1 minute and a half. Appearance in milk. — Upon treating the matter as in the preceding experiment, it gives to the fluid a very luminous appearance, which lasts from 15 to 20 minutes; the brilliancy dependent upon the quantity of matter introduced. In Oil. — The luminous appearance remains in this medium for the space of three or four days. Upon rubbing the im- mersed flesh against the sides of the glass, it became more vivid. In Alcohol. — Upon immersion in this fluid, it is extin- guished in the space of two minutes. It does not impart to the alcohol the same appearance as is observed in the water or milk. Heat. — Immediately extinguished, upon being placed in boiling water and heated air. Cold. — Upon placing a portion in a glass, and suspending the glass in a freezing mixture, no effect was observed after the lapse of 30 minutes. Effects in the Diluted Mineral Acids. — Strength of solution 6 fluid drachms of acid to 2 fluid ounces of water. Sulphuric Acid. — Extinguished almost immediately. Nitric Acid. — Effect not so immediate as the preceding. Muriatic Acid. — Not so immediate as the nitric. Diluted Vegetable Acids. — Solution same proportions as above. Acetic Acid. — Soon out after immersion. Tartaric Acid. — Not so immediate as preceding. Oxalic Acid. — Requires a longer period than tartaric. Diluted Alkalies. — Ammonia. — Extinguished on immer- sion. Potassa. — In this medium some time is required to extin- guish the luminosity. Muriate of Soda.*— A strong solution of this substance extinguishes it almost immediately. It would be difficult to state the true nature of the cause of this phaenomenon. From oiy* own observations, and the results 426 Royal Society: Prof. Farada^^'s Experimental of the above experiments, we are inclined to believe that it is the effect of a peculiar state of decomposition, totally inde- pendent of atmospheric causes, the luminosity residing (to the best of our belief,) in the oily matter, which we observed upon submitting it to microscopic examination : we hope how- ever, that at some future period, we may have an opportunity of observing the same phaenomenon, and continuing our re- searches. 82, Blackfriars Road, London. LXX. Proceedings of Learned Societies, ROYAL SOCIETY. [Continued from p. 368.] Feb. 15, A Paper was in part read, entitled " Experimental Re- 1838. -^^ searches in Electricity," Twelfth Series, by Michael Faraday, Esq., D.C.L., F.R.S., &c. February 22. — The reading of a paper, entitled, " Experimental Researches in Electricity," Twelfth Series, by M. Faraday, Esq., D.C.L., F.R.S., was resumed. March 1. — The reading of a paper, entitled "Experimental Re- searches in Electricity," Twelfth Series, by Michael Faraday, Esq., D.C.L., F.R.S., &c., was resumed and concluded. Ewperimental Researches in Electricity : Twelfth Series. By Mi- chael Faraday, Esq., D.C.L., F.R.S., Fullerian Professor of Che- mistry in the Royal Institution of Great Britain. The object of the present series of researches is to examine how far the principal general facts in electricity are explicable on the theory adopted by the author, and detailed in his last memoir*, re- lative to the nature of inductive action. The operation of a body charged with electricity, of either the positive or negative kind, on other bodies in its vicinity, as long as it retains the whole of its charge, may be regarded as simple induction, in contradistinction to the effects which follow the destruction of this statical equiUbrium, and imply a transit of the electrical forces from the charged body to those at a distance, and which comprehend the phenomena of the electric discharge. Having considered, in the preceding paper, the process by which the former condition is established, and which con- sists in the successive polarization of series of contiguous particles of the interposed insulating dielectric ; the author here proceeds to trace the process, which, taking place consequently on simple in- duction, terminates in that sudden, and often violent interchange of electric forces constituting disruption, or the electric discharge. He investigates, by the application of his theory, the gradual steps of transition Avhich may be traced between perfect insulation on the one hand, and perfect conduction on the other, derived from the * See our present volume, p. 358. Researches in Electricity ; Twelfth Series, 427 varied degrees of specific electric relations subsisting among the par- ticular substances interposed in the circuit : and from this train of reasoning he deduces the conclusion that induction and conduction not only depend essentially on the same principles, but that they may be regarded as being of the same nature, and as differing merely in degree. The fact ascertained by Professor Wheatstone, that electric con- duction, even in the most perfect conductors, as the metals, requires for its completion a certain appreciable time*, is adduced in corrobo- ration of these views ; for any retardation, however small, in the transmission of electric forces can result only from induction ; the degree of retardation, and, of course, the time employed, being pro- portional to the capacity of the particles of the conducting body for retaining a given intensity of inductive charge. The more perfect insulators, as lac, glass and sulphur, are capable of retaining electri- city of high intensity ; while, on the contrary, the metals and other excellent conductors, possess no power of retention when the in- tensity of the charge exceeds the lowest degrees. It would appear, however, that gases possess a power of perfect insulation, and that the effects generally referred to their capacity of conduction, are only the results of the carrying power of the charged particles either of the gas, or of minute particles of dust which may be present in them ; and they perhaps owe their character of perfect insulators to their peculiar physical state, and to the condition of separation under which their particles are placed. The changes produced by heat on the conducting power of different bodies is not uniform; for in some, as sulphuret of silver and fluoride of lead, it is increased ; while in others, as in the metals and the gases, it is diminished by an augmentation of temperature. One peculiar form of electric discharge is that which attends eleC' trolyzation, an effect involving previous induction; which induction has been shown to take place throughout linear series of polarized particles, in perfect accordance with the views entertained by the author of the general theory of inductive action. The peculiar fea- ture of this mode of discharge, however, is in its consisting, not in a mere interchange of electric forces at the adjacent poles of con- tiguous particles, but in their actual separation into their two con- stituent particles; those of each kind travelling onwards in contrary directions, and retaining the whole amount of the force they had ac- quired during the previous polarization. The lines of inductive ac- tion which occur in fluid electrolytes are exemplified by employing for that purpose clean rectified oil of turpentine, containing a few minute fibres of very clean dry white silk; for when the voltaic circuit is made by the introduction into the fluid of wires, passing through glass tubes, the particles of silk are seen to gather together from all parts, and to form bands of considerable tenacity, extending between the ends of the wires, and presenting a striking analogy to the arrangement and adhesion of the particles of iron filings between the poles of a horse-shoe magnet. * See Lond. and Edinb. Phil. Mag. vol. vi. p. 61. 428 Royal Society. The fact that water acquires greater power of electrolytic induc- tion by the addition of sulphuric acid, which not being itself decom- posed, can act only by giving increased facihty of conduction, is ad- duced as confirming the views of the author. The phenomena of the disruptive electric discharge are next ex- amined with reference to this theory : the series of inductive actions which invariably precede it are minutely investigated : and reference is made to the accurate results obtained by Mr. Harris, as to the law of relation between the intensity of a charge, and the distance at which a discharge takes place through the air. The theory of Biot and others, which ascribes the retention of a charge of electricity in an insulated body to the pressure of the sur- rounding atmosphere, is shown to be inconsistent with various phe- nomena, which are readily explained by the theory adopted by the author. The author then enters into an inquiry relative to the specific con- ducting capacities of different dielectrics. With a view of determining the degrees of resistance to the transit of electricity excited by different kinds of gases, he constructed an apparatus, in which an electric discharge could be made along either of two separate channels ; the one passing through a receiver filled with the gas, which was to be the subject of experiment, and the other having atmospheric air interposed. By varying the length of the passage through the latter, until it was found that the discharge occurred with equal facility through either channel, a measure was afforded of the relative resistances in those two lines of transit, and a determination consequently obtained of the specific insulating power of the gas employed. The circumstances attending the diversified forms of the disruptive discharge, such as the vivid flash or spark, the brush or pencil of light, and the lucid point or star, which severally represent different conditions of the sudden transit of electrical forces through an inter- vening dielectric, are minutely investigated in their various modifi- cations. The spark is the discharge, or reduction of the polarized inductive state of many dielectric particles, by the particular action of a few of those particles occupying but a small and limited space, leaving the others to return to their original or normal condition in the inverse order in which they had become polarized : and its path is determined by the superior tension which certain particles have ac- quired, compared with others, and along which the action is accord- ingly conducted in preference to other lines of transit. The variety in the appearance of the electric spark taken in different gases may be ascribed partly to different degrees of heat evolved, but chiefly to specific properties of the gas itself with relation to the electric forces. These properties appear also to give occasion to diversities in the form of the pencU or brush, which takes place when the discharge is incomplete, and is repeated at short intervals, according to the shape of the conductor on either side, and according to the species of electricity conveyed. The diverging, converging, bent and rami- fied lines presented in these different forms of electric discharge. Royal Society. 429 strikingly illustrate the deflexions and curvilinear courses taken by the inductive actions which precede the disruption ; these lines being not unlike the magnetic curves in which iron filings arrange them- selves when under the action of opposite magnetic polarities. March 8. — A paper was read, entitled, " Proposal for a new method of determining the Longitude, by an absolute Altitude of the Moon," by John Christian Bowring, Esq. Communicated by John George Children, Esq., F.R.S. The method employed by the author for determining the longitude by the observation of an absolute altitude of the moon, was pro- posed, many years ago by Pingre and Lemmonier; and the princi- pal difficulty which stood in the way of its adoption, was its re- quiring the exact determination of the moon's declination reduced to the place of observation. This difficulty the author professes to have removed by supposing two meridians for which the altitudes are to be calculated : and the only remaining requisite is the accu- rate determination of the latitude, which presents no great difficulty, either on land or at sea. Examples are given of the practical work- ing of this method ; showing that if the latitude of a place of obser- vation be obtained within a few seconds, the longitude will be found by means of a single observation of the altitude of the moon. A paper was also read, entitled, " An Inquiry into a new Theory of earthy Bases of Vegetable Tissues," by the Rev. J. B. Reade, M.A., F.R.S. The author, after briefly noticing the results of some of his expe- riments described in two papers which appeared in the Philosophical Magazine for July and November, 1837, and also those of Mr. Ro- bert Rigg in a paper read to the Royal Society*, next adverts to the theory of M. Raspail, detailed in his Tableau Synoptique, and Nou- veau Systeme de Chimie. In opposition to some of the views enter- tained by the latter, he finds that in the bark of the bamboo and the epidermis of straw the silica incrusting these tissues is not crystal- lized, but, on the contrary, exhibits, both before and after incinera- tion, the most beautiful and elaborate organization, consisting of au arranged series of cells and tubes, and differing in its character in different species of the same tribe, and in different parts of the same plant. The observations of Mr. Golding Bird, contained in the 14th number of the Magazine of Natural History, New Series, are then referred to ; and the author states in confirmation, that, by employ- ing caustic potash, the siliceous columns may be removed from the leaf of a stalk of wheat, while the spiral vessels and ducts, which form the principal ribs of the leaf, as well as the apparently metallic cups which are arranged on its surface, remain undisturbed. He proposes, therefore, to substitute, in the description of vegetable tissues, the term skeleton, instead of that of bases, whether saline or siliceous, of those tissues. March 15. — The reading of a paper, entitled, ''Experimental • Sec Lend, and Edinb. Phil. Mag., vol. ix. p. 635. *30 Eoyal Society: Prof. Faraday*s Experimental Researches in Electricity," Thirteenth Series, by Michael Faraday, Esq., D.C.L., F.R.S., &c., was commenced. March 22. — A paper was read, entitled, " Description of a new Tide- Gauge, constructed by T. G. Bunt, and erected on the Eastern bank of the River Avon, in front of the Hotwell House, Bristol, in 1837." Communicated by the Rev. William Whewell, M.A., F.R.S. The principal parts of the machine here described, are an eight- day clock, which turns a vertical cylinder, revolving once in twent}'- four hours ; a wheel, to which an alternate motion is communicated by a float rising and falling with the tide, and connected by a wire with the wheel which is kept constantly strained by a counterpoise ; and a small drum on the same axis with the wheel, which by a sus- pending wire communicates one 18th of the vertical motion of the float to a bar carrjdng a pencil which marks a curve on the cylinder, or on a sheet of paper wrapped round it, exhibiting the rise and fall of the tide at each moment of time. The details of the mechanism, illustrated by drawings, occupy the whole of this paper. A paper was also read, entitled, " On the R6gar or Black Cotton Soil of India," by Capt. Newbold, Aide-de-Camp to Brigadier-Ge- neral Wilson. Communicated by S. H. Christie, Esq., M.A., Sec. R.S. The author states that the Regar of India is found, by chemical analysis, to consist of silica, in a minute state of division, together with lime, alumina, oxide of iron, and minute portions of vegetable and animal debris. Hence it is usually considered as having been formed by the disintegration of trap rocks : the author, however, after examining its numerous trap dykes traversing the formation of the ceded districts, which he found invariably to decompose into a ferruginous red soil, perfectly distinct from the stratum of black regar through which the trap protrudes, was led to regard this opi- nion of its origin as erroneous : and from the circumstance of its forming an extensive stratum of soil covering a large portion of the peninsula of India, he believes it to be a sedimentary deposit from waters in a state of repose. Specimens of basaltic trap and of the Regar soil were transmitted to the Society by the author, for the purpose of analysis. The reading of a paper, entitled, "Experimental Researches in Electricity," Thirteenth Series, by Michael Faraday, Esq,, D.C.L., F.R.S. , &c., was resumed but not concluded. March 29, 1838. — The reading of a paper, entitled, "Experi- mental Researches in Electricity," Thirteenth Series, by Michael Faraday, Esq., D.C.L., F.R.S., was resumed but not concluded. April 5, 1838. — The reading of a paper, entitled, "Experimental Researches in Electricity," Thirteenth Series, by Michael Faraday, Esq., D.C.L., F.R.S., was resumed and concluded. The author, in this paper, pursues the inquiry into the general differences observable in the luminous phenomena of the electric discharge, according as they proceed from bodies in the positive or the negative states, with a view to discover the cause of those dif- Researches in Electricity ; Thirteenth Series, 431 ferences. For the convenience of description he employs the term inductric, to designate those bodies from which the induction ori- ginates, and inducteous to denote those whose electric state is dis- turbed by this inductive action. He finds that an electric spark, passing from a small ball, rendered positively inducteous, to another ball of larger diameter, is considerably longer than when the same ball is rendered positively inductric, and that a similar difference, though to a less extent, is observable, when the smaller ball is ren- dered negative. The smaller ball, rendered positive, gives also a much longer spark than when it is rendered negative ; in which latter case, however, it affords, at equal distances, a luminous brush of greater size, and gives it much more readily than when positive. In order to ascertain the relative degrees of charge which the balls acquire before the occurrence of the discharge, the author employed an apparatus attached to the insulated conductor of the electrical machine, and also to the conductor connected with the discharging train, and consequently uninsulated, consisting, on each side, of a rod branching out in the form of a fork, and terminating, at one of its extremities in a large ball, and at the other in a small one ; the position of the forks being capable of adjustment, so that the large ball of each rod might be brought exactly opposite to the small one of the other : and the distances between each pair admitted of being regulated at pleasure, until the discharges through each interval were rendered apparently equal to one another. From numerous experiments made with this instrument, the author concludes that when two conducting surfaces of small but equal size, are placed in air, and electrified, the one positively and the other negatively, a discharge takes place at a lower tension from the latter than from the former ; but that, when a discharge does occur, a greater quan- tity of electricity passes at each discharge from the positive, than from the negative surface. Experiments of a similar nature were made in gases of different kinds, by enclosing them in an apparatus constructed on the same plan as the former one, but capable of act- ing in a receiver, from which the air could be exhausted, and the particular gas, whose powers in modifying the electric discharges were to be ascertained, could be introduced in its place. The results of various trials are given in a table, from which it appears that different gases restrain the discharge in very different degrees. The discharge from the small ball, through nitrogen and hydrogen gases, most readily takes place when the charge is positive ; and through oxygen, carbonic acid, and coal gas, when it is negative. The author next directs his attention to the peculiar luminous phenomena attending the disruptive electrical discharge, which he terms a glow, and which appears to depend on a quick, and almost instantaneous charge given to the air in the immediate vicinity, and in contact with the charged conductor ; and he enters into a de- tailed account of the circumstances by which it is influenced, and its production favoured ; such as diminution of the charging sur- face, increase in the power of the machine, rarefaction of the sur- rounding air, and the particular species of electricity concerned. The relations which the glow, the brush, and ,the spark bear to one 432 Royal Society. another, as well as the steps of transition between each are minutely investigated ; and the conclusion is deduced that the glow is in its nature exactly the same as the luminous part of a brush or ramifi- cation, namely, a charge of air ; the only difference being that the glow has a continuous appearance from the constant renewal of the same action in the same place, whereas the ramification is occa- sioned by a momentary and independent action of the same kind. The disruptive discharge may take place at degrees of tension so low as not to give rise to any luminous appearance ; so that a dark space may intervene in the line of actual discharge, as is frequently observable between the brush on one side, and the glow on the other. Thus it is inferred that electric light is merely a consequence of the quantity of electricity which, after a discharge has com- menced, flows and converges towards the spot where it finds the readiest passage : and these conclusions are further confirmed by the phenomena which take place in other gases, besides atmospheric air, and which are specifically detailed by the author. The last kind of discharge which is here considered is the con- vective or carrying discharge, namely, that effected by the transla- tion of charged particles from one place to another. The phenomena attending this mode of transference are examined under various aspects as they occur in air, in liquids of various kinds, in flame, and as they are exhibited in the case of particles of dust, which perform the office of carriers of the electricity; and also in that of solids terminated by liquids. Thus all these apparently isolated phenomena comprised under the heads of the electric currents which characterize electrolyzation, of transference through dielectrics by disruptive discharges of various kinds, or by the actual motion of charged particles, and of conduction through conductors of various degrees of power, are assimilated to one another by their being shown to be essentially the result of actions of contiguous particles of matter assuming particular states of polarization. The author lastly considers electric currents, not only in their effects on the bodies they traverse, but also in their collateral in- fluences as producing inductive and magnetic phenomena. The analogies, which connect electrolytic discharge with that by con- duction, are pointed out, as tending to show that they are essentially the same in kind, and that when producing different kinds of mo- tion in the particles of matter, their mode of operation may be re- garded as identical. An attempt is made to connect with these views the lateral or transverse actions of currents, which are most distinctly manifested in their magnetic effects ; these effects being produced equally by the disruptive, the conductive, and the electro- lytic discharges, and probably depending on the transverse condition of the lines of ordinary induction. This transverse power has the character of polarity impressed upon it, and, in its simplest form, appears as attractive or repulsive, according as the currents them- selves are in the same, or in opposite directions. In the current and in the magnet it assumes the condition of tangential force ; and in magnets and their particles it produces poles. The author announces that he intends shortly to develop, in an- Geological Socieli/, 433 other series of these researches, some further views which he enter- tains concerning the nature of electric forces and electric excitation in connexion with the theor)' he has here advanced. . The Society then adjourned over the Easter Recess to meet again on the 26th of April. GEOLOGICAL SOCIETY. Annual General Meeting, Feb. 16*. After the reading of the usual reports, the President presented the Wollaston Medal to Mr. Richard Owen, and, on doing so, said, Mr. Owen, I have peculiar pleasure in presenting to you this Medal, awarded to you by this Society for your services to Fossil Zoology in general, and, in particular, for the description of the Fossil Mammalia collected by Mr. Darwin. I trust it will be a satisfaction to you to receive this our testimony of the success with which you have cultivated that great science of comparative zoology, to which you have devoted your powers. I trust it will add to your satisfaction to consider that the subject which we more peculiarly wish to mark on this occasion, in the study of Fossil Zoology, is one to which the resources of your science were applied, while the subject was yet new, by that great man, John Hunter, whose Museum and whose reputation are so worthily as- signed to your care. I trust also that this Medal thus awarded to you at the outset, if I may so say, of an enlarged series of investi- gations, will convey to you the assurance that, in your progress in such researches, you carry with you our strong interest in your en- deavours, and our high esteem of your powers and your objects; and will convince you that in all your successes, you may reckon upon our most cordial sympathy in the pleasure which your discoveries give. ' Mr. Owen acknowledged his sense of the distinction conferred upon him in the following terms: — I wish. Sir, that I had words adequately to express my deep sense of the honour I have now received ; but I feel assured that you will grant to me the sincerity of my brief acknowledgments. The study of the animal organization has always abundantly repaid me by the pleasure which naturally flows from the contemplation of the mar- vellous skill with which, in the complete frame of existing species, structures are modified and designed in relation to particular ends ; and from the perception of a subordination of the various instruments to one general plan. But since I have pursued anatomical invest: - gations in connection with fossil remains, I have been rewarded by new and extrinsic pleasures. I trace to this source my connexion with the Geological Society, and the possession of some most valued friendships ; and now. Sir, my obligations to the Society, and to Pa- laRontology are increased ten-fold by the unexpected honour I have this day received at your hands. I receive this testimony of your good opinion as a strong stimulus to future endeavours. I cannot * The papers read previously to the Anniversary will be noticed in future numhers. Phil, Mag. S. 3. Vol. 12. No. 76. May 1838. 2 P 434« Geological Society, permit myself to regard it as a reward for the inadequate contri- butions which I have hitherto been able to make to the history of lost species ; and I pledge myself to lose no available time or oppor- tunity which may be applied to further that branch of geological science which has the extinct animals of this planet for its immediate object. The following gentlemen were elected the Officers and Council for the ensuing year. Pre5^c?e/^^.— Rev. William Whe well, M.A.F.R.S. Vice-Presidents. —William Henry Fitton, M.D. F.R.S. & L.S.; Charles Lyell, Jun. Esq. F.R.S. & L.S.; Roderick Impey Murchison, Esq. F.R.S. & L.S.; Rev. Adam Sedgwick, F.R.S. & L.S. Secretaries. — Charles Dar- win, Esq.; William John Hamilton, Esq. Foreign Secretary. — H. T. De la Beche, Esq. F.R.S. & L.S. Treasurer.— iohn Taylor, Esq. F.R.S. & L.S. Council— Rem^ Boase, M.D. F.R.S.; Rev. William Buckland, D.D. F.R.S. L.S. ; Viscount Cole, M.P. D.C.L. F.R.S.; Charles Giles Bridle Daubeny, M.D. F.R.S. L.S.; Sir P. Grey Egerton, Bart. M.P. F.R.S.; G. B. Greenough, Esq. F.R.S. & L.S.; Leonard Horner, Esq. F.R.S. L. & E.; Robert Hutton, Esq. M.P. M.R.LA.; Sir Charles Lemon, Bart. M.P. F.R.S.; Marquis of Northampton, F.R.S.; Richard Owen, Esq. F.R.S.; Sir Woodbine Parish, K.C.H. F.R.S.; John Forbes Royle, M.D. F.R.S. & L.S.; T. Weaver, Esq. F.R.S. M.R.LA. Address delivered by the Rev. William Whewell, M.A. F.R.S. President, Gentlemen, You have heard in the Reports just read, statements which show that the Society is in a state of healthy progress both in respect to its numbers and its funds. The total number of Fellows of the So- ciety, exclusive of Honorary and Foreign Members, at the close of the year 1836, was 709. At the close of the last year it was 738, the increase being 29, after deducting 18 Members deceased or re- signed. A Part of the Transactions has recently been published, which is worthy of its predecessors in the interest of its matter, and which is not inferior to them in its appearance and illustrations. I believe it will be found that improvements have been introduced, especially in the colouring of the maps. Our collections have also gone on increasing, and have, as in pre- vious years, derived great additional value from the labour and know- ledge bestowed upon them by our excellent Curator. But your Council has found itself compelled to attend to the great, and I may say intolerable amount of labour which has fallen upon Mr. Lonsdale, and certain alterations in the Society's arrangements, directed to the object of remedying this evil, are now in progress or in contemplation. When they are completed I shall have the satisfaction of announcing them to the Society. The Council have awarded the Wollaston Medal, as you have al- ready been informed, to Mr. Richard Owen, for his general services Anniversary of IS^S, Address of the President, 435 to Fossil Zoology, and especially for his labours employed upon the fossil mammalia collected by Mr. Darwin in the voyage of Captain Fitz Roy. I need not remind you. Gentlemen, how close are the ties which connect the study of living and of fossil animals ; how much light the progress of comparative anatomy throws upon the inter- pretation of geological characters ; and what important steps in our knowledge of the past condition of the earth are restorations of the animal forms which peopled its surface in former times, but have long vanished away. Since the immortal Cuvier breathed into our science a new principle of life, the value of such researches has ever been duly appreciated ; and the award of the WoUaston Medal last year is an evidence how gladly your Council take that method of congra- tulating the successful cultivators of such studies. I am sure that all who are acquainted with Mr. Owen's labours will rejoice that we have in this manner marked our sense of his success. His earlier researches, those for instance on the Nautilus, have been of exceeding use and interest to geologists. And the first part of his description of the fossil mammalia, collected by Mr. Darwin in South America, contains matters of the most striking novelty, interest, and import- ance. We have there the restoration, performed with a consummate skill, such as fitly marks the worthy successor of Hunter and the disciple of Cuvier, of two animals, not only of new genera, but occupying places in the series of animal forms, which are peculiarly instructive. For the one, the Toxodon, connects the Rodentia with the Pachyder- mata by manifest links, and with the Cetacea by more remote resem- blances ; and thus contributes to the completion of the zoological scale just in the parts where it is weakest and most imperfect ; while the other animal, the Macrauchenia, the determination of which is con- sidered by anatomists as an admirable example of the solution of such a problem, appears to be exactly intermediate between the horse and the camel. But this creature is also interesting in another way, since it closely resembles, although on a gigantic scale, an animal still existing in that country and peculiar to it, the Llama. Thus, in this as in some other instances, the types of animal forms which distinguish a certain region on the earth's surface are clearly reflected to our eyes as we gaze into the past ages of the earth's history, while yet they are mag- nified so as to assume what almost appear supernatural dimensions. The Llama, the Capybara, and the Armadillo of South America are seen in colossal forms in the Macrauchenia, the Toxodon, and the Me- gatherium. I will not omit this occasion of stating that the profound and enlarged speculations on the difFusion,preservation, and extinction of races of animals to which Mr. Darwin has been led by the remains which he has brought home, give great additional value to the trea- sures which he has collected, and make it proper to off*er our con- gratulations to him, along with Mr. Owen, on the splendid results to which his expedition has led and is likely to lead. Mr. Owen and Mr. Darwin are engaged in the restoration of other animals from the South American remains in their possession, and I am able to announce that two or three other new genera have already been de- tected. I am sure I am conveying your feeling. Gentlemen, as well 2P2 i 3 G Geological Society. as my own, when I express a cordial hope that these two naturalists, so fitted by their endowments and character to advance the progress of science, may long go on achieving new triumphs ; and may have the satisfaction — higher even than that which they derive from the honours we so willingly bestow — of finding the great principles which it is given to them to wield, becoming every year more powerful in- struments of discovery; and of seeing, as they pursue their researches, light thrown upon the darkest and widest of the vast problems which they have proposed to themselves. I will now say a few words concerning a few of the most con- spicuous of the names which have been obliterated by death from our list during the year. Among the members of our body, whom we have lost there is one whom we cannot but mention with more than common emo- tion, endeared as he was to many of us by private friendship, and admired by all for his talents, his knowledge, and his services. Dr. Edward Turner, Professor of Chemistry in the London University, filled the office of our Secretary for five years, and subsequently was two years Vice-President, which situation he held at the time of his death in February 1837. Several of you may remember, Gentle- men, that our last anniversary meeting was in some measure clouded by the recollection of this then recent calamity ; and that many of the Fellows of the Society, on that occasion, expressed their inten- tion of testifying their respect and regard for the departed by attending his funeral. Of Dr. Turner's private virtues, and of the charm of his society, I must not here speak. I will not allow myself to dwell upon the admirable clearness and precision of his thoughts as expressed in conversation, — upon the delightful openness and candour of his character, — upon the kind and gentle cheerfulness of his demeanour, the genuine fruit of a deep habitual religious feeling. But I may take this occasion to say, that in him chemistry suffered a loss, not only great, — for that all would at once say, — but much greater and more difficult to repair than may at first sight appear. Dr. Turner entertained a conviction (I am stating the result of many interesting conversations which I have held with him) that the time was come when the chemist could not hope to follow out the fortunes of his science, and to read in her discoveries their full meaning, with- out being acquainted with the language, and master of the resources of mathematics. Acting upon this enlightened view, he did not hesitate to encounter the great labour and exertion of a course of study in the higher mathematics; and he succeeded entirely in making himself a good mathematician. And he was one 'of the very few who, in our country, labour at a branch of chemistry which is of the highest importance to us as geologists ; but which, — we may suppose from its laborious and intricate nature, — appears to repel our most active che- mists ; I mean that portion of chemistry which is connected with mineralogy. Yet this department is, in truth, more inviting than it may at first appear. No doubt in it clear mathematical conceptions are necessary, and perhaps some little training in mathematics ; but there is good An?iiver sari/ of IS38. Address of the President, 437 promise that the labour which this line of investigation demands will be rewarded. I am fully persuaded that there is no portion of the frontier line of our knowledge of which we can so certainly say, " Here we are on the brink of great discoveries." Had Dr. 7 urner been spared to us some years longer, I know no one who was more likely to have had a principal share in such discoveries. Two papers of his, in the Philosophical Transactions,* show that he was able to deal with the atomic theory in a mode which combines the resources of the skilful analytical chemist with the rigour of the mathematical reasoner ; a combination which the right prosecution of that theory requires, but which has not always been found in its cultivators. Dr. Turner lectured on chemistry at the London University from its first foundation in 1828; he was there surrounded by students, whose affection he gained by his kindness, as well as their admi- ration by the clearness of his teaching. He also gave a course of lectures on geology, in conjunction with Dr. Grant and Mr. Lindley, each of those gentlemen taking a division of the subject with which he was most familiar. Dr. Turner was snatched from science at the early age of thirty-nine, having been born in the island of Jamaica in 1796. He studied anatomy at Edinburgh, and chemistry at Got- tingen, under the able chemist Friedrich Von Stromeyer, to whom he dedicated his Elements of Chemistry; a work which has had, as it well deserves, a very wide circulation among students f. In William Parish, B.D., Jacksonian Professor of Natural and Experimental Philosophy in the University of Cambridge, the Society has lost an honorary member, elected as such soon after its original foundation, namely in November 18Q8, and one of a number of our countrymen who were at that period placed upon the honorary list. Professor Parish never employed himself peculiarly in geological pur- suits as we now understand the term ; but it is to be recollected, that within a few years of the date of his election, which I have men- tioned, the investigation of the earth's structure made a rapid progress, and, in consequence, assumed a more fixed and technical form. Pro- fessor Parish's scientific studies were mainly directed to the arts, manufactures, and machinery of the empire ; on these subjects he delivered courses of lectures full of interest and instruction ; and he was thus led to describe our mines, and the mode of working them. But no reference to particular portions of Professor Parish's labours can convey a just notion of the impulse which he gave to the progress of scientific knowledge within his own sphere of influence, by the habit of seizing, with an active and vivid apprehension, upon prominent parts of modern science, and conveying them, in a manner singularly clear and simple, to his audience. Por a long course of years his lectures were more eflficacious than any other circumstance in stimulating the minds of men in his university to philosophical thought on physical • On the Composition of Chloride of Barium, 1829 ; Researches on Atomic Weights, 1833. [See Phil. Mag. and Annals, N.S., vol. viii. p. 180; and L. and E. Phil. Mag. vol. i. p. 109; iii. p. 448.— Edit. t [See also present volume, p. 275.] 438 Geological Society, subjects ; and to this day these lectures are never mentioned by those who attended them at that period, without admiration and pleasure. His merit was well recognised by the university in which he spent his life. He received the highest mathematical honours of that body on taking his degree of B. A. in 1778, was elected Professor of Che- mistry in 1794, and Jacksonian Professor in 1813 ; and at the insti- tution of the Cambridge Philosophical Society in Nov. 1819, he was its first president. I cannot refrain from adding, that although I have here to speak of him principally as a man of science, such pursuits were in his case little more than episodes, in a life the main action of which was di- rected to the ends of religion and benevolence. In his duties, as a minister of Christianity, he was most zealous and indefatigable ; and every attempt to relieve the misery, the ignorance, the unjust restraints of any portion of mankind, found in him a strenuous advocate and ready agent. His childlike simplicity, genuine kindness of heart, and untiring religious earnestness were such as well suited his kindred with Bernard Gilpin, " the Apostle of the North," from whom, through his mother, he derived his descent. He was born at Carlisle in 1759, and died at the age of 78. Henry Thomas Colebrooke, member of the Supreme Council of Cal- cutta, was one of those extraordinary men whom our Indian empire has produced ; and who show the animating effects of the great scene in which they are there placed, by the variety of subjects to which they extend their attention, and by the vigour with which they combine speculative and practical employment. Mr. Colebrooke went to India as a writer in 1782, and about 1792 began to attend pecu- liarly to Sanscrit literature. A little later we find him beginning to enrich the Asiatic Researches with a series of memoirs on the religion, the literature, and, above all, the science of the Hindoos. In this department his labours on the Zodiac of the Indians*, and on their notions of the Precession of the Equinoxes and the motions of the Planetsf, are highly deserving of notice ; as were at a later period the account of the Indian Algebra, given in his translations of the Lilawati and Vijaganita. But Mr. Colebrooke was also ready to con- tribute a share in sciences with which we are more nearly concerned. He took a lively interest in the correction of errors respecting the physical geography of India, and was one of the first to declare (in 1815) his opinion that the Himalaya mountains were higher than the Andes, an opinion soon afterwards fully confirmed. He also was one of the first to enter upon a subject, to which we may now look with the greatest hope. The first part of vol. i. of our New Series of Transactions (published in 1822) contains two papers by him, one upon the geology of the valley of the Sutledge, which had been ex- plored by Lieut. Gerard ; the other upon the north-east of Bengal, where Mr. D. Scott had noticed various rocks, and, among the rest, a deposit which contained fossils, resembling, as he conceived, those of the London clay. I shall have occasion, in the course of this ad- • Asiat. Res., vol. ix. t Ibid., vol. xii. Anniversary of 1858. Address of the President. 439 dress, to refer to a recent repetition of this observation of an identity between the fossils of the east of India and those of the London and Paris basin. I may observe that these, and other contributions to In- dian geology by other writers, contained in the volume of which I spoke, and a preceding one, induced the Secretaries of that time to insert a map, on which the localities of these observations were in- dicated ; and to express in the volume a hope, that these were merely an earnest of the information which might be expected from the activity of British subjects in that quarter*. Among our foreign members deceased within the year, I regret much to have to mention one, to whom is due, in no small degree, a revolution in the mode of treating the subject of geology, which has taken place in our own times, and the formation of a new branch of geology. This revolution consists in the endeavour, now so fa- miliar to us, to identify geological with recent changes, instead of classifying the great past changes in the surface of the earth which its structure discloses to us, as separate from the newer and slighter modifications of which history and tradition gives us evidence ; and the study of the discernible causes of change to which we are thus led, I shall have occasion to speak of under the name of Geological Dy- namics. You are well aware that Mr. Lyell is the person who has, with a bold and vigorous hand, moulded the whole scheme of geo- logy upon this idea ; but the power which he had of doing this was derived in no small degree from Von Hoif's admirable survey of the evidence of those changes which can be proved by tradition. The extent and universality of the facts thus brought into notice, might well forcibly strike a philosopher already seeking to apply such a principle to geology ; and Mr. Lyell has always been forward to acknowledge his obligations to M. Von HofF. Indeed the idea of such an identification of geological with historical changes was by no means new; it had been both expressed and acted on by Deluc ; and must have been present to the minds of those persons who framed the ques- tion which gave rise to Von HofF's book. This question was proposed in 1818 by the Royal Academy of Science of Gottingen. " Consider- ing," they said, **that we have, in the crust of the earth, evidence of great revolutions, which have happened at diiFerent times, in dififerent portions, and of which the period and duration are unknown, we are led to ask whether certain more partial alterations may not lie within the domain of tradition, and give us the means of knowing at what period they took place, and what time the formation of certain por- tions of the earth's crust required ; whereby some light may be thrown on those changes which lie beyond the limits of history." M. Von Hoff's work, — " The history of those natural changes in the earth's surface which are proved by tradition" — appeared (the first part) in 1822, and had the Academy's prize assigned it. This part of the work contained an account of the changes due to the agency of water ; and by the wide range of reading and study which • [Another notice of Mr. Colebrooke has appeared in our present volume, p. 272.— Edit.] 44-0 Geological Society. it included, and the philosopliical manner in which its copious ma- terials were arranged, well justified the distinction which it received. The view presented in it of the great changes which have gone on from the beginning of historical times, — the yielding or advancing of coasts, the disappearing of islands, the union of seas, — appear to give a new face to the globe. But the portion of the judgement of the Academy which the author most valued was, that in which they said that he had used the sources of his information conscientiously. In 1824 appeared the second part, containing the history of volcanos and earthquakes ; and, although the previous labours of Humboldt and Von Buch had done much to connect and generalise facts of this kind, Von Hoff's labours were an important step : " At least," he himself says, " he was not aware that any one before him had en- deavoured to combine so large a mass of facts with the general ideas of the natural philosopher, so as to form a whole." Among other large views, we may see much which, as to kind of change supposed, agrees with the opinions of Mr. Darwin, of which I shall have to speak ; for instance. Von Hoff conceives that the island of Otaheite is under- going a gradual elevation out of the sea.* Finally, the third volume of this work appeared after an interval of ten years, in 1 834 ; in which he considers other causes of change; as rising and sinking of the land; alterations of rivers and seas ; the operations of snow and ice ; and also the geological results to which the whole survey had led him. In this volume he expresses his pleasure at the appearance of Mr. Lyell's work, which had taken place in the intervening period, and by which he had found much new light thrown upon his own speculations. In the interval of time between the publication of the second and third volumes, M. Von HofF published " Geological Observations on Carlsbad," (1825) and " Measures of Heights in and near Thuringia" (1833). In this last work he not only gave a great number of his own barometrical measurements, but discussed all extant measures of the heights of points in Thuringia, to the amount of above 1100. He also employed himself in meteorological observations. Karl Ernest Adolph Von Hoff, Knight of the order of the White Falcon, and invested with several offices of honour and dignity at the Ducal Court of Gotha, died at Gotha the 24th of May last. He was QQ years of age, having been bom in the same city Nov. I, 1771. Besides the history I have mentioned, which must always continue to be a classical work on the subject of which it treats, he was at the time of his death employed in compiling a continuation of his Notices of Earthquakes and Volcanic Eruptions ; and also a new work, which was considered to be an important one, and was to be entitled " Germany according to its Natural Conditions and Political Relations." * Part II. Pref. p. xiv. [To be continued.] I 441 ] ZOOLOGICAL SOCIETY. [Continued from p. 216.] January 24, 1837 (continued). — Mr. Martin described a species of Foa^ brought by Mr. Darwin from the island of Chiloe, respecting which he made some remarks which will be found in No. xlix. of the Proceedings. He characterized it under the specific title fulvipes* . The Secretary read a communication from J. O. Westwood, Esq., describing several new species of Insects belonging to the family of the Sacred Beetles. After noticing the interest which is attached to the family of the Scarabaeidce, not only on account of their curious habits, whence they were raised to the rank of objects of worship by the Egyptians, but also from having led to the publication of the Hora Entomologies by Mr. MacLeay, in which an analysis of the Linnsean Scarahcei was given ; the author gives an abstract of the classifications of this fa- mily respectively proposed by MacLeay, Latreille, (Regne An., 2nd edition), and Serville and Saint Fargeau {Encyclop. Method, vol. x.), with a notice of the genera more recently proposed by various authors referrible or allied thereto. From a review of these distributions in conjunction with the natural economy of the insects of which the fa- mily is composed, the author is disposed to consider the family as divisible into two natural groups, those with long hind legs and those which have their legs short and conical ; and also that the characters of the genus Scarabceus and subgenus Heliocantharus must either be modified so as to exclude the species which are destitute of a distinct spur at the extremity of the intermediate tibice, or that the Ateuchus Adamastor (Enc. Meth.) and the insects subsequently described must be regarded as referrible to the genus Scarabceus, although possessing two spurs at the extremity of the intermediate tibia, agreeing in all other material respects with the true Scarabai. The following is an abstract of the characters of the insects, the descriptions of which were accompanied by figures exhibiting the various essential organs in detail, and by observations upon the structural peculiarities of the two groups. TypUS SCELIAGES. CorpMS latum, subdepressum. CapM^ subtrigonum clypeo trilobato, lobo intermedio vald^ emarginato. Antenna clava subglobos£i, arti- culo 7"™° magno infern^ producto, articulos duos terminales in sinu ejus includente, ultimo 8vo minori. Palpi maxillares breves sub- filiformes, labiales abbreviati 3-articulati, articulis magnitudine de- crescentibus. Thorax abdomine pauUo latior. Tibia anticae magnse, pone medium intus curvatse. Tibice intermediae bicalcaratse. Species, Sceliages lopas, from South Africa. * In order to avoid repetition we will here state that in all cases in which new species or groups are stated to have been characterized, in our reports of the meetings of the Zoological Society, their characters will be found in the" Proceedings" of the Society for the meeting in question. — Edit. 442 Zoological Societtf, Typus Anomiopsis. Pedes elongati, tiM(B intermediae curvatae bicalcaratae, calcaribus mobilibus intemo, elongate acuto, externo breviori spatuliformi, tarsi pedum anticorum obsoleti, quatuor posticorum depress! setosi, un- guibus nullis ; palpi maxillares filiformibus, articulis tribus ultimis longitudine fere aequalibus ; labiales dilFormes, articulo 2do maximo transverso-ovato, ultimo minutissimo intern^ et obliqu^ inserto. Species, Anomiopsis Dioscorides, from Patagonia, and Aniom. Sterquilinus, of unknown locality. Mr. Martin called the attention of the meeting to a specimen of the Dasypus hyhridus, in the collection presented to the Society by C. Darwin, Esq. This animal, the tatou mulet of Azara, has been characterised in all systematic works, as closely related to Dasypus Peba, and as having large ears ; whereas the ears are much smaller than in D. Peha, and but little larger than those of D. minutus. In reference to this species, which he at first was unable satisfactorily to identify, he observed that the vague and unsatisfactory account given in systematic works would, he conceived, justify him in laying before the meeting a more complete and definite description of the animal than he had been able to meet with, the want of which he had himself experienced, which he thus ventured to supply. The description appears in No. xlix. of the Proceedings. Mr. James Reid exhibited to the Meeting, and characterized as new, under the name of Obscurus, a dark- coloured monkey, from the Society's collection, belonging to the genus Semnopithecus. The locality of the particular specimen before the Meeting was unknown. February 14, 1837. — A letter was read from C. R. Read, Esq., a corresponding member, dated Singapore, September 2nd, 1836, an- nouncing a present of 56 skins of birds, and the skin of an alligator of large size, which have been received. At the request of the Chairman, Mr. Waterhouse brought under the notice of the Meeting numerous species of the genus Mus, form- ing part of the collection presented to this Society by Charles Dar- win, Esq., a Corresponding Member. The specimens placed on the table had been collected at various parts of the Southern Coast of South America, viz. Coquimbo, Valparaiso, Port Desire, Maldonado, Bahia Blanca, &c. Most of these numerous species were considered by Mr. Water- house as hitherto undescribed, and drawings were exhibited by him illustrative of the modifications observable in their dentition. The characters, dimensions, and particular habitats of the species above referred to are given in No. I. of the Society's Proceedings, under the following specific names ; viz. Mus tumidus, nasutus, obscurus, longipilis, olivaceus, micropus, brachyotis, xanthorhinus, canescens, arenicola, bimaculatus, ele- gans, gracilipes, flavescens, brevirostris, and Maurus. After giving the characters, &c., of the above new species of Mus» Mr. Waterhouse proceeds as follows : " Though in the foregoing description I have retained the ge- Mr. Waterhouse on new species oJMus, 4-13 neric title Mus, I have here to state that the above species natu- rally divide themselves into several subordinate groups, the characters of which are sufficiently evident, not only between themselves, but also between each group and that to which the term Mus ought, I conceive, to be restricted, and of which our common mouse {Mus musculiis) may be regarded as the type. To these groups I shall here assign subgeneric titles, and at the same time point out their chief distinguishing characters without entering into any minute details respecting them, as I sliall shortly have an opportunity of illustrating my views by means of drawings both of the teeth and of the animals, without which it is impossible to convey a clear idea of the subject/* Subgenus 1. Scapteromys*. Molars with enamel deeply indented in the crown. In the front molar of the lower jaw the enamel is indented twice on the outer margin and three times on the inner; in the second molar the enamel is indented once on the outer margin and twice on the inner ; and in the last molar once on the outer, and twice on the inner. Fur long and soft. Tail moderate, well clothed with hair. Claws long, but slightly curved and formed for burrowing. Fore-feet mode- rately large. Thumb furnished with a distinct claw. Ears moderate, well clothed with hairs. Species Mus {Scapteromys) tumidus. Subgenus 2. Oxymycterus t. Molars with the folds of enamel penetrating deeply into the body of the tooth. Front molar of the lower jaw with three indentations on the inner side and two on the outer ; second molar with two on the outer side and the same number on the inner ; the last molar with one indentation of the enamel on each side. Fur long and soft. Claws long, but slightly curved, and formed for burrowing. A di- stinct claw on the thumb. Tail short, moderately furnished with hair. Nose much elongated and pointed. Species Mils {Oxymycterus) nasutus. Subgenus 3. Abrothrix|. Folds of enamel penetrating deeply into the sides of the molars. The front molar of the lower jaw has three folds of enamel on the inner side and two on the outer ; the second molar has two on the inner side and one on the outer ; and the last molar has one on each side. Fur long and soft. Tail short, well furnished with hair. Thumb vdth a short rounded nail. Ears well furnished with hair. Type Mus {Abrothrix) longipilis. Species 2 Mu^ (-46.) obscurus. .„____ 3 olivaceus. 4 micropits. »______ 5 br achy Otis. 6 xanthorhinus, ' 7 canescens. 8 • arenicola, • Scapteromys, from 2««TT»jg, a digger, and My;, t Oxymycterus, from O^vj, sharp, and Mj/«t»jj, n< X Abrothrix, from ' A/3go^ soft or delicate, and ©g/ m O^vs, sharp, and Mvktvi^, nose. A/3go^ soft or delicate, and ©g/$, hair. 444« Zoological Society. In general appearance these animals resemble ArvicotcB. Subgenus 4. Calomys*. Fur moderate, soft. Tarsus almost entirely clothed beneath with hair. Front molar with three indentations of enamel on the inner side and two on the outer ; second molar with two on the inner and two on the outer ; and the last molar with one on each side. Type Mus {Calomys) bimaculatus. Species 2 Mus (Cal.) elegans. 3 graxiilipes. Mus Tftiaurus and M. brevirostris I regard as belonging to the re- stricted genus Mus. In Mus Jlavescens the dentition differs slightly from that of the ordinary mice. Mr. Gould exhibited, in continuation, the Fissirostral Birds of Mr. Darwin's collection recently presented to the Society, and characterized from among them the following new species : viz. Caprimulgus hifasciatus, and Caprim. parvulus ; Hirundo frontalis and Hirund. Concolor ; and Halcyon Erythrorhynchus : the charac- ters, dimensions, and habits of all which will be found in No. I. ol Society's Proceedings. February 28, 1837. — A notice by T. C. Eyton, Esq. of some oste- ological peculiarities in different skeletons of the genus Sus was read; which has appeared in No. I. of the Proceedings. A letter was read from Thomas Keir Short, Esq., dated Launces- ton. Van Diemen's Land, August 10th, 1836, containing some re- marks upon the Apteryx, two living specimens of which had been seen by the writer. The general correctness of the description pub- lished by Mr. Yarrellf of this bird is confirmed by the observations of Mr. Short, with the exception of its progressive powers, which are stated to be remarkably great. The natives employ two methods of capturing it ; one by hunting it down with very swift dogs, the other by imitating its call at night, and when by this means the bird is decoyed within a short distance, it is suddenly exposed to a strong light, which so confuses it that it is then readily taken. The usual position is standing, with the head drawn back between the shoul- ders, and the bill pointing to the ground. The food is stated to be principally worms and insects, and these birds are strictly nocturnal in their habits, feeding only during the night. Mr. Short remarks, that he has not been able to learn the place in which the Apteryx builds its nest, or the number of eggs which it lays. In conclusion, he promises to use his utmost endeavours to procure specimens for the Society. Mr. Gould resumed the exhibition of his collection of Australian Birds, as also several species, from the same country, forming por- tions of the collections of the United Service Museum, and of King's College, London. Among his own birds Mr. Gould characterized two new species of Meliphagida, constituting a subdivision of that * Calomys, from KeeXo^ beautiful, and VLvc. t See Lend, and Edinb. Phil. Mag. vol. iii. p. 299. Mr. Waterhouse on ntw Rodenlia. 445 family, including Meliphaga tenuirostris of authors. For this new group he proposed the generic title of Acanthorhynchus, and for the two new species the names of A. superciliosus and A. dubius. Acanthorhynchus. (Gen. char.) Rostrum elongatum gracile et acutum ; ad latera compressum ; tomiis incurvatis ; culraine acuto et elevato. Nares basales elongatse et operculo tectae. Lingua ut in Gen. Meliphaga. Alee mediocres et sub-rotundatse, remigibus primis et quintis fer^ sequalibus ; tertiis et quartis intense aequalibus et longissimis. Cauda mediocris, et paululiim furcata. Tarsi elongati, fortes ; halluce digito medio longiore et robustiore ; digito externo medium superante. Ungues curvati. Typus, Certhia tenuirostris, auct. The following species, also in Mr. Gould's collection, were named and characterized ; viz. Pardalotus affinis, Nanodes elegans, Platycercvs Jlaveolus, and HiMANTOPUs leucocephalus. Mr. Gould also characterized under the following names two new species of the genus Stertia, from the collection in King's College, a species oi Cormorant in the United Service Museum, and three spe- cies of the genus Orpheus, from the Galapagos, in the collection of Mr. Darwin. Sterna poliocerca and Stern, macrotarsa; Phalacrocorax bre- virostris ; and Orpheus trifasciatus, 0. melanotis and 0. parvulus. Mr. Waterhouse resumed the exhibition of the small Rodents, belonging to the collection presented by Mr. Darwin to the Society. Among them were three species allied to the genus Mus, but offering some slight modification, not only in the external form, but in the structure of the teeth. They have the fur soft and silky ; the head large, and the fore legs very small and delicate ; the tarsus mode- rately long and bare beneath ; in the number and proportion of the toes they agree with the true rats ; the tail is moderately long, and more thickly clothed with hair than in the typical rats. The ears are large, and clothed with hair. Like the true rats, they have twelve rooted molars ; the folds of enamel, however, penetrate more deeply into the body of each tooth, and enter in such a way that the crowns of the teeth are divided into transverse and some- what lozenge- shaped lobes, or in some instances into lobes of a triangular form. In the front molar of the upper jaw the enamel enters the body of the tooth twice, both on the outer and inner sides ; and in the second and posterior molars, both of the upper and under jaws, the enamel penetrates but once externally and in- ternally in each. In the front molar of the lower jaw the enamel enters the body of the tooth three times internally, and twice ex- ternally. As the above-mentioned characters, in Mr. Waterhouse's opinion, evidently indicated an aberrant form of the Muridae, he suggested 446 Zoological Society, the propriety of constituting a subgenus under the name of Phyllo- tis* for the reception of the species. They were characterized as Mus (Phyllotis) Darwinii, xantho- pygus, and griseo-flavus. For their characters and dimensions, &c. see Proceedings. Two species of small Rodents were next characterized as consti- tuting examples of a new genus, for which Mr.Waterhouse proposed the name of RElTHRODON.f Denies primores f ; inferioribus acutis, gracilibus, et antic^ Isevi- bus ; superioribus gracihbus, antic^ longitudinalitfer sulcatis. Molares utrinque f radicati ; primo maximo, ultimo minimo : primo superiore plicas vitreas duas extern^ et intern^ altematim ex- hibente ; secundo, et tertio, plicas duas extern^, intern^ unam : primo inferiore plicas vitreas tres extern^, duas intern^; se- cimdo, plicas duas extern^, unam intern^ ; tertio unam extern^ et intern^, exhibentibus. Artus insequales : antipedes 4-dactyli, cum poUice exiguo unguiculato : pedes postici 5-dactyli, digitis extemis et intemis brevissimis. Ungues parvuli et debiles. Tarsi subtiis pilosi. Cauda mediocris, pilis brevibus adpressis instructa. Caput magnum, fronte convexo : oculis magnis : auribus mediocribus. *• In the present genus, the incisors, compared with those of the true rats, are rather smaller in proportion, and those of the upper jaw also differ in having a longitudinal groove, a character which exists in Euryotis (Brants), Gerbillus, Otomys (Smith), Dendromys, and some other genera, but not combined with molars similar in structure to those above described, nor yet with similar external characters. In other respects the incisors resemble those of the genus Mus ; that is to say, those of the lower jaw are long, slender, and pointed, and those of the upper are deep from front to back, and somewhat flattened at the sides and in front. The molars gradually decrease in size from the front to the last posterior tooth. The folds of enamel penetrate deeply into the crowns of these teeth, so that those from one side are in contact vnth those of the other; these folds of enamel are each nearly opposed to the salient angles of the opposite side. " In the two species of this genus with which I am acquainted the fur is long, very soft, and consists of hairs of two lengths. The arched form of the head and the large eyes produce in these ani- mals a slight resemblance to young rabbits ; their aflSnity, however, is with the Murida." Mr. Waterhouse then gave the characters of Reithrodon ty pious and Reith. cuniculo'ides. * Phyllotis, from .7\.ov, a leaf, and Owj, urog, an ear. t Tuffpot, a channel ; 03o*, a tooth. Mr. Waterhouse on new Rodeniia. 44<7 In conclusion, two other new Rodents were characterized under the generic name of Abrocoma.* Denies primores f acuti, eradicati, antic^ Iseves : molares utrinque f subsequales, illis maxillae superioris in areas duas transver- sales ob plicas vitreas acut^ indentatas divisis ; plicis utriusque lateris vix aequ^ profundis ; illis mandibulse inferioris in tres partes divisis, plicis vitreis bis intern^, semel extern^ indenta- tis, area prima sagittae cuspidem fingente, cseteris acut^ trian- gularibus. Artus subaequales. Antipedes 4-dactyli, extemo brevissimo, intermediis longissimis et fer^ sequalibus. Pedes postici 5-dactyli; digito intemo brevissimo. Ungues breves et debiles, illo digiti secundi lato et lamellari ; omnibus setis rigidis obtectis. Caput mediocre, auribus magnis, membranaceis; oculis mediocribus. Cauda breviuscula. Vellus perlongum, et moUe. *' The genus Abrocoma is evidently allied on the one hand to Oc- todon, Ctenomys, and Poephagomys, and it appears to me almost as evidently allied on the other hand to the Chinchillida. llie denti- tion, however, differs considerably from either of the above-men- tioned genera, or from either of those of the family Chinchillida, and in fact indicates a new generic form f . From Ctenomys and Pcephagomys the present genus is readily distinguished, by the comparatively large size of the ears, the small delicate claws, and smaller size of the inci- sors; and from Octodon by the uniform length of the hairs on the tail. " In the structure of the feet the genus Abrocoma approaches very nearly to Octodon, not only in the form but in having the soles both of the fore and hind feet (which are devoid of hair) covered with mi- nute round fleshy tubercles. In Octodon, however, the toes have on their under side transverse incisions as observed in the Muridce, a character, however, not found in Abrocoma ; here the under side of the toes is, like the sole of the foot, covered with tubercles. ** The extreme softness of the fur of the animals about to be de- scribed, suggested for them the generic name of Abrocoma. The fur consists of hairs of two lengths, and the longer hairs are so ex- tremely slender that they might almost be compared to the web of the spider. The specific names {Abrocoma Bennettii and A. Cuvieri, applied are those of the distinguished naturalists who first made us acquainted with the two genera Octodon and Pcephagomys, these being very nearly allied to Abrocoma." March 14, 1837. — A paper was read, " On the habits of the Vul- tur aura," by Mr. W. Sells, with notes of dissections of the heads of two specimens, by Mr. R. Owen. • 'A/3/jOf, soft; Kof*vi, hair. t " I may here mention that the folds of enamel in the dentition of the lower jaw very much resemble those in the teeth of the genus Arvicola" 448 Zoological Society, The writer states that this bird is found in great abundance in the Island of Jamaica, where it is known by the name oiJohn Crow ; and so valuable are its services in the removal of carrion and animal filth, that the legislature have imposed a fine of £5 upon any one destroy- ing it within a stated distance of the principal towns. Its ordi- nary food is carrion, but when hard pressed with hunger it will seize upon young fowls, rats, and snakes. After noticing the highly offen- sive odour emitted from the eggs of this bird when broken, Mr. Sells relates the following instances which have come under his own per- sonal observation, for the purpose of proving, that the Vultur aura possesses the sense of smell in a very acute degree. " It has been questioned whether the vulture discovers its food by means of the organ of smell or that of sight. I apprehend that its powers of vision are very considerable, and of most important use to the bird in that point of view ; but that it is principally from highly organized olfactories that it so speedily receives intelligence of where the savory morsel is to be found will plainly appear by the following facts. In hot climates the burial of the dead commonly takes place in about twenty-four hours after death, and that necessarily, so ra- pidly does decomposition take place. On one occasion I had to make a post-mortem examination of a body within twenty hours after death, in a mill-house, completely concealed, and while so engaged the roof of the mill-house was thickly studded with these birds. Another instance was that of an old patient and much-valued friend who died at midnight : the family had to send for necessaries for the funeral to Spanish Town, distant thirty miles, so that the interment could not taJie place until noon of the second day, or thirty- six hours after his decease, long before which time, and a most painful sight it was, the ridge of the shingled roof of his house, a large mansion of but one floor, had a number of these melancholy-looking heralds of death perched thereon, beside many more which had settled in trees in its immediate vicinity. In these cases the birds must have been directed by smell alone as sight was totally out of the question. " In opposition to the above opinion, it has been stated by Mr. Au- dubon that vultures and other birds of prey possess the sense of smell in a very inferior degree to carnivorous quadrupeds, and that so far from guiding them to their prey from a distance, it affords them no indication of its presence, even when close at hand. In confirmation of this opinion he relates that he stuffed the skin of a deer full of hay and placed it in a field ; in a few minutes a vulture alighted near it and directly proceeded to attack it, but finding no eatable food he at length quitted it. And he further relates that a dead dog was con- cealed in a narrow ravine twenty feet below the surface of the earth around it and filled with briers and high canes ; that many vultures were seen sailing in all directions over the spot but none discovered it. I may remark upon the above experiments that in the first case the stag was doubtless seen by the birds, but it does not follow that they might not also have smelt the hide, although inodorous to the human nose ; in the second case, the birds had undoubtedly oeen attracted by smell, however embarrassed they might have been Zoological Society. 449 by the concealment of the object which caused it. I have in many hundred instances seen the vulture feeding upon small objects under rocks, bushes, and in other situations where it was utterly impos- sible that the bird could have discovered it but through the sense of smell ; and we are to recollect that the habit of the vulture is that of soaring aloft in the air, and not that of foraging upon the ground." Mr. Sells's communication was accompanied by the following let- ter from Mr. Owen, addressed to the Secretary, W. Yarrell, Esq. " Dear Sir, — I received the heads of the John Crow, which I sup- pose to be the Vultur aura or Turkey Buzzard, and have dissected the olfactory nerves in both ; as also in a Turkey which seemed to me to be a good subject for comparison, being of the same size, and one in which the olfactory sense may be supposed to be as low as in the Vulture, on the supposition that this bird is as independent of assistance from smell in finding his food as the experiments of Audu- bon appear to show. There is, however, a striking difference be- tween the Turkey Vulture and the Turkey in this part of their organi- zation. The olfactory nerves in the Vulture arise by two oval ganglions at the anterior apices of the hemispheres from which they are con- tinued 1 J line in transverse diameter, and 2 lines in vertical diameter, and are distributed over well- developed superior and middle spongy bones, the latter being twice the dimensions of the former. The nose is also supplied by a large division of the supraorbital branch of the 5 th pair, which ascends from the orbit, passes into the nose crossing obliquely over the outer side of the olfactory nerve, extend- ing between the superior spongy bone and the membrane covering the middle spongy bone, then descending, and after supplying the inferior and anterior spongy bone escaping from the nasal cavity to supply the parts covering the upper mandible. This olfactory branch of the 5th pair is about :J;th the size of the true olfactory nerve. " In the Turkey the olfactory branch of the 5th ner\T is about the same size as in the Vulture, and is superior in size to the true olfac- tory nerve, which is only about ^th the size of that in the Vulture. The olfactory nerve does not form a ganglion at its commencement, but is continued as a small round chord from the anterior apex of each hemisphere, and is ramified on a small middle spongy bone, there being no extension of the pituitary membrane over a superior turbinated bone as in the Vulture. Indeed the difference in the development of the nasal cavity is well marked in the different forms of the head in these two species. In the Vulture there is a space between the upper parts of the orbits in which the olfactory gan- glions and nerves are situated, and the nasal cavity anterior to these is of a much greater breadth and also longer, as well as exhibiting internally a greater extent of pituitary surface, than in the Turkey. In this bird the olfactory nerves are compressed within a narrow in- terorbital space, which would not admit of the lodgement of gan- glions; the olfactory nerves after passing through this space then di- verge to the nasal cavity. " In the Goose the olfactory nerves are developed to the same size as in the Vulture, and expand upon superior spongy bones of similar Phil. Mag, S. 3. Vol. 12. No. 76. Mai/ 1838. 2 Q 450 Zoological Society, form, but placed wider apart, and these supply the middle spongy bones which are longer but not so broad as in the Turkey. The olfactory branch of the 5th pair is double the size of that in the Vulture or Turkey ; it gives, however, not a greater proportion of filament to th^ nose than in those birds, but is mainly expended upon the membrane covering the upper mandible. f'The above notes show that the Vulture has a well-developed organ of smell, but whether he finds his prey by that sense alone, or in what degree it assists, anatomy is not so well calculated to ex- plain as experiment. " I will bring my preparations showing the above at next meeting, and am truly yours, " Royal College of Surgeons, March 7th." " R. OwEN." Mr. Gould brought before the notice of the meeting, from the col- lection of Mr. Darwin, a new species of Rhea from Patagonia, and after offering some observations upon the distribution of the Stru- thionidce, and upon the great interest attending this addition to that family, he remarked that the new species is distinguished from Rhea Americana of authors, in being one-fifth less in size, in having the hill shorter than the head, and the tarsi reticulated in front in- stead of scutellated, and in being plumed below the knee for several inches. It has also a more densely plumed wing, the feathers of which are broader, and all terminated by a band of white. Mr. Gould, in conclusion, adverted to the important accessions to science resulting from the exertions of Mr. Darwin, and to his libe- rality in presenting the Society with his valuable Zoological Collec- tion ; to commemorate which he proposed to designate this interest- ing species by the name of Rhea Darwinii. Mr. Darwin then read some notes upon the Rhea Americana, and upon the newly described species, but principally referring to the former. This bird abounds over the plains of Northern Patagonia and the United Provinces of La Plata ; and though fleet in its paces and shy in its nature, it yet falls an easy prey to the hunters, who confound it by approaching on horseback in a semicircle. When pursued it generally prefers running against the vrind, expanding its wings to the full extent. It is not generally known that the Rhea is in the habit of swimming, but on two occasions Mr. Darwin witnessed their crossing the Santa Cruz river, where its course was about 400 yards wide and the stream rapid. They make but slow progress, their necks are extended slightly forwards, but little of the body appears above water. At Bahia Blanca, in the months of October and September, an extraordinary number of eggs are found all over the country. The eggs either lie scattered about, or are collected together in a shallow excavation or nest; in the former case they are never hatched, and are termed by the Spaniards Huachos. The Gauchos unani- mously afiirm that the male bird alone hatches the eggs, and for some time afterwards accompanies the young. Mr. Darwin does not doubt the accuracy of this fact, and states that the cock bird Royal Institution of Great Britain, 45 1 sits so closely that he has almost ridden over one in the nest. Mr. Darwin has also been positively informed that several females lay in one nest, and altho\igh the fact at first appears strange, he considers the cause sufficiently obvious, for as the number of eggs varies from 20 to 50, and, according to Azara, even 70 or 80, if each hen were obliged to hatch her own before the last was laid, the first probably would have been addled ; but if each laid a few eggs at successive periods in different nests, and several hens, as is stated to be the case, combine together, then the eggs in one collection would be nearly of the same age. Mr. Burchell mentions that in Africa two ostriches are believed to lay in one nest. Mr. Darwin then proceeds to notice the other species of Rhea, which he first heard described by the Gauchos, at River Negro, in Northern Patagonia, as a very rare bird, under the name of Avestruz Petise. The eggs were smaller than those of the common Rhea, of more elongated form, and with a tinge of pale blue. This species is tolerably abundant about a degree and a half south of the Rio Negro, and the specimen presented to the Society was shot by Mr. Martens at Port Desire in Patagonia, (in latitude 48). It does not expand its wings when running at full speed, and Mr. Darwin learned from a Patagonian Indian that the nest contains fifteen eggs, which are deposited by more than one female. It is stated in conclusion that the Rhea Americana inhabits the country of La Plata as far as a little south of the Rio Negro, in lat. 41°, and that the Petise takes its place in Southern Patagonia. Mr. Chambers then brought before the notice of the Society a simple process for taking impressions from feathers, which is effected by placing the feathers between two sheets of paper, the lower one being previously well damped, and the upper covered with printers* ink; both are then passed through the rolling press of a copper plate printer, and on removing the upper sheet perfect figures of the fea- thers will be left, which may be coloured when dry, and will then have the resemblance of feathers placed on paper. FRIDAY EVENING MEETINGS AT THE ROYAL INSTITUTION. Jan. 19, 1838. — Mr. Faraday on Electrical Induction. Jan. 26. — Mr. Brande on the nature of fatty bodies, and on the application of stearine to the manufacture of candles. Feb. 2. — Mr. Goadby on the skeleton of insects. Feb. 9. — Mr. Gray on the formation and structure of shells. Feb. 16. — Dr. Ainsworth on the progress of the alluviums of Babylonia. Feb. 23. — Mr. Faraday on the atmosphere of this and other planets. March 2. — Mr. Carpmael on the manufacture of welded iron tubing. March 9. — Mr. Griffiths on the philosophy and manufacture of the various means for obtaining instantaneous lights. March 16. — Mr. Pereira on the relation between the external form and the optical and other characters of crystals. 2Q2 452 Cambridge Philosophical Society, March 23. — Mr. Cowper on the manufacture of lace by machinery. March 30. — Dr. Grant on the metamorphosis of the Amphibia. April 6. — Mr. Faraday on Mr. Ward's plan of preserving and growing plants in closed vessels and places. CAMBRIDGE PHILOSOPHICAL SOCIETY. A meeting of this Society was held on Monday evening, February 26th, the Rev. L. Jenyns, Vice-President, in the chair. Various presents of books were announced, and the following papers were read : — On some new genera of fossil multilocular shells in the slate rocks of Cornwall, by Mr. Ansted, of Jesus College ; On a question in the Theory of Probabilities, by Mr. De Morgan ; On the Quadra- ture of the Circle, by Dr. CressweU. A meeting of this Society was held on Monday evening, March 12th, the Rev. the Master of Christ's College, the President, being in the chair. Mr. Kelland, of Queen's College, read the first part of a paper On Molecular Attraction. Afterwards Professor Henslow gave an account of the plants brought by Mr. Darwin from the Keeling Islands. These are coral islets of recent formation, lying to the south of Sumatra. They are of the form called lagoon islands, the average height of the land above the water not being more than six feet. These islands have only recently been inhabited by man. The indigenous vegetable species from them are 24 in number, and Mr. Darwin has brought home 22 of these, belonging to 21 genera, and 18 different families. March 26th. — The Rev. Dr. Graham, the President, in the chair. Professor Challis read a paper On the Proper Motions of the Stars. Mr. Airy read the termination of a paper " On the Intensity of Light in the neighbourhood of a Caustic," of which the following is an abstract. Taking V to represent the length of the path from a source of light to any point of a reflecting surface (or, mutatis mutandis, of a refracting surface), and thence to a ■point at which the intensity of light is to be estimated, and putting X for the ordinate of the point of the reflecting surface, -^^ — - has a finite value at all points, except when the point whose dx ordinate is x is the same with the point which, on the ordinary laws of reflexion, would reflect light to the point under consideration ; for that point , = 0. From this the author deduced that, if the dx point under consideration were a conjugate focus, receiving the rays reflected from the whole surface, V must be constant, or the whole series of differential coefficients must vanish ; but if the point under consideration is the focus only for a very small pencil reflected from the point whose ordinate is x, and from neighbouring points, then d (V) rf2 /y) — ^^ — - = 0, and — r— ^ = 0, without any condition for the remam- dx dx'^ ^ ing diflferential coefficients. From the nature of the caustic it is Cambridge Philosophical Society. 453 evident that these equations must apply to every point of the caustic, provided that x have the value corresponding to the point of reflection on the ordinary law ; but it may be shown also that, in dUY) general, J" ^ is finite, and admits of being expressed in terms of the radius of curvature of the caustic and other lines. Having found d (V) rf2 c V) rf3 CV) therefore, that in the caustic — ^ = 0, , ^ = 0, , ^ = C, dx dx'^ dx^ the proper value being given to j?, the author infers that, for a point at the distance $p from the caustic, \ ■ will = A.^o, , ■■ dx ^ dx"^ = B ^p, = C + D . ^p. The values of A and C are easily found. Consequently the value of V, for a point at the distance Bp from the caustic, when measured through a point of the reflecting surface, whose ordinate is x-\-z, is of the form \<+AJp. '- +BJp . ^^(C-^n.ip) — . Rejecting the unimportant parts of the coefficients, and altering z so as to take away the second power, this becomes V + A ? o . «' Q + -— z^^ : the expression for the disturbance of ether is 6 which, observing that / , sin [K^p.z^^ "F'^'^J ^^tween — infinity and + infinity = 0, may in all cases be shown to be proportional to sin ivt —Y] x / cos — {w^—m,w\ the integral being taken from w = 0 to w = infinity, and m being ex- pressed in terms of A, C, Bp, and \. Putting S for the definite in- tegral from w = 0 to w = infinity, the intensity of light therefore is proportional to [nr 12 Sm; cos —■ {w^ — m.w) I . The author then considers especially the case of the rainbow (in- cluded in the general case of the deviation of rays having a maximum or minimum), and shows that it depends on the same expression. An account was then given of the way in which the value of the definite integral had been found for forty-one diiferent values of m (be- ginning with m = — 4*0, — 3*8, &c. and ending with m = -}- 4-0). As far as z^ = 2'0, it was found by summation ; after that, by series. The series possessed the property of diverging indefinitely after some assignable term, yet of having a sum always finite. The pro- cess was one of considerable labour. 454 Intelligence aiid Miscellaneous Articles, From the result of these calculations it appeared that the place of greatest intensity was not at the caustic but on its convex side, or (for the rainbow) within the primary bow : that the intensity was no where infinite ; that it diminished most rapidly on the concave side of the caustic ; that on the convex side, after having increased to a maximum, it diminished to 0, and then increased to a second maximum, whose value M'as about |^ths of the first. The calculations did not extend to the next evanescence of light. The following rule was given for ascertaining the place of the geometrical rainbow (on the theory of emission) : measure the distance between the bright bow and the first spurious bow ; the geometrical bow is exterior to the bright bow by -ir^ths of this quantity. LXXI. Intelligence a7id Miscellaneous Articles, GRESHAM COLLEGE. [As some of our correspondents have formerly endeavoured to call attention to the subject of Gresham College, we have given the following brief notes of Pro- fessor Pullen's admirable Lectures, and have much satisfaction in pointing out to those who are desirous of attending to astronomical and physical studies a means of improvement which is freely open to the pubUc. It is greatly to be wished that the Gresham trustees would second and encourage the efforts of the Professors, by affording the lectures the advantage of the requisite illustrations. The usefulness of Mr. Pullen's would have been very much increased had he been suppUed with diagrams large enough to be seen by the audience.] ON Friday, April 20th, Mr. PuUen the Professor of Astronomy, commenced a course of three lectures on the tides. In the first lecture he explained the general phsenomena of tides according to Bernoulli's, or the Equilibrium Theory. The earth being supposed a sphere covered with water to a certain depth, the attraction of the moon would have the effect of throwing that water into the form of a prolate spheroid, of which the upper pole is raised by the excess of the moon's attraction on the waters immediately subjected to her influence over that on the general mass of the earth ; the lower re- sults from a similar relative effect, the greater attraction of the moon on the mass of the earth subtracting it from the water. This spheroid will follow the moon at a certain interval ; and a spectator on the earth's surface in the course of 24^48"^ (alunar day,) will be sensible of two tides, one by a passage through the upper, another by a passage through the lower pole. An effect similar to that of the moon is produced by the sun, but in a less degree. There will, therefore, be a tidal spheroid at a certain distance from the moon, and another tidal spheroid of greater dimensions following the moon. These eflfects in their combinations give rise to the semimenstrual inequal- ity as well in the height of the tide as in the lunitidal interval. At the moon's conjunction and opposition the two effects are combined, and the result is spring tide ; when the moon is in quadratures, the elevation due to one spheroid is partly counteracted by the depres- sion due to the other, and the result is the phaenomena of neap tides. The lecturer proceeded to show the effect which the monthly varia- Intelligence and Miscellaneous Articles. 455 tion of the moon's distances from the earth, as evidenced by the va- riation of her horizontal parallax from 54' to 61', is calculated to produce both in the height of the tide and in the lunitidal interval ; as well as the smaller effect attributable to the annual variation of the moon's distances. The highest possible spring tide is that which follows a new or full moon in the month of January, the moon being at the same time in perigee. The first lecture concluded with an explanation of the diurnal inequality, or difference in the heights of the superior and inferior tides depending upon the moon's declination, and the consequent inclination of the axis of the tidal spheroid to the plane of the equator. The moon being in the equator the superior and inferior tides are equal; but when the moon is in north declination the superior tide is greater than the inferior in north latitudes, and less than the inferior in south lati- tudes. The contrary effect is produced when the moon has south declination. In the second lecture, the lecturer explained the mode in which tide observations had been conducted, and the manner in which they may be made to exhibit the different inequalities which theory leads us to expect. He particularly instanced the observations made at the London Docks from the year 1808 to the year 1826, from which tables were calculated by Mr. Lubbock, and published in the Philo- sophical Transactions for 1831. Grouping together observations made in different years, but in the same month, and corresponding to the same half hour of the moon's transit, we may eliminate the effects of winds and errors of observation by taking their mean ; and thus a table of lunitidal intervals is constructed for every month of the year, and every half hour of the moon's transit. The variation of the intervals in this table is called the calendar month inequality, and this is eliminated by taking the mean of the horizontal columns. The mean intervals are given under the head " mean," in the last vertical column. Two inequalities explained by theory are involved in this table : 1 . the annual inequality de- pending upon the position of the sun in his orbit; and 2. the in- equality depending upon the moon's declination ; for the sun, occu- pying a definite place in his orbit, and the moon following the sun at a given time, she must necessarily have a certain specific declina- tion. Neglecting, therefore, the annual inequality, the same result will be obtained, whether we compute the times of high water by a calendar month table, or by the column of mean transits and a de- clination table. This table, however, does not exhibit the effects of parallax ; it is therefore necessary to group observations according to the values of the moon's horizontal parallax ; and then by sub- tracting these quantities from the corresponding mean values such effects are exhibited. Tables thus constructed show that the luni- tidal interval is diminished, and the height of the tide increased by the increase of the moon's parallax ; a result to which theory also leads us. The greatest variation in the lunitidal interval at the London Docks is about 38"*, the greatest variation in height about IJ feet. The lecturer then proved that the diurnal inequality is 456 Intelligence and Miscellaneous Articles, also to be discovered by observation. At the London Docks it is small ; but at Liverpool it makes nearly one foot of difference be- tween the superior and inferior tides. This inequality may be seen by inspection of the tables, but it is exhibited more clearly in the zigzag form of the curve traced out by laying down the successive heights of high water as ordinates, and taking the corresponding times as abscissae. A very remarkable peculiarity in the diurnal inequality is, that while the semimenstrual and other inequalities correspond very accurately to the fourth transit of the moon pre- ceding the tide, this inequality corresponds as uniformly to the fifth, a fact which can only be accounted for by supposing (what also appears from other considerations,) that all the circumstances of the tides as observed in the northern hemisphere, depend upon condi- tions existing in the southern hemisphere, and that they are propa- gated from thence northwards, simply by the mechanical laws of undulations in fluids. The third lecture was on the comparison of tidal observations in different parts of the world made with a view of tracing the progress of the tide. This theory is entirely of recent origin, being solely attributable to Mr. Whewell, who has justly remarked in his " Essay towards a first approximation to a Map of Cotidal lines," contained in the Philosophical Transactions for 1833*. that no attempt had till tl:en been made to answer decisively the inquiry which Bacon sug- gested to the philosophers of his time, " whether the high water extends across the Atlantic, so as to affect contemporaneously the shores of America and Africa, or whether it is high on one side of this ocean when it is low on the other." The lecturer first showed what would be the motion of the tide wave on a sphere covered with water, and then considered the manner in which it would be affected by continents and islands, inland seas and bays. He also showed how the tide would be obliterated by the propagation of a series of undulations in opposite directions, differing in their epoch by six hours ; and the modifying effects they would mutually pro- duce when they differed by other intervals. The tides of different ports are compared by a comparison of their establishments. The " vulgar establishment" is the time of high water immediately fol- lowing the new or full moon. This involving the semimenstrual inequality as well as the longitudinal difference of the port, a more correct form is obtained by Mr. Whewell in his second essay (Phil. Trans. 1836, p. 293,) by taking the mean of the greatest and least lunitidal intervals, correcting for the moon's parallax and declina- tion, and her motion in JR, and referring the whole to Greenwich time. The establishment thus corrected is called the cotidal hour of the port. At the instance of Mr. Whewell, a request was made by the British Association for the Advancement of Science, to the British Government to procure a series of simultaneous tide observations to be made on the shores of Europe and America, in order to ascertain accurately the places of contemporaneous high water. In pur- • See p. 354 of the present volume. Intelligence atid Miscellaneous Articles, 457 suance of this object, simultaneous observations were made during twenty days of the month of June, 1835, at about 500 places, ex- tending from Florida to Nova Scotia on one shore of the Atlantic, and from Gibraltar to the North Cape of Norway on the other. At the same time similar observations were made at the several coast guard stations round the British Islands. The lecturer exhibited maps on which cotidal lines, or lines of contemporaneous high water, were laid down. These maps to a great extent verify the conclu- sions at which we arrive by theory. The tide wave raised in the southern ocean is propagated up the Atlantic northward ; it then pursues its course round the northern coast of Scotland, and along the eastern shores of England, till it finally arrives at the mouth of the Thames. At the same time derivative tides are propagated through St. George's and the British Channels ; so that these tides meeting with those which arrive from the north of Ireland in the one case, and the north of Scotland in the other, produce inter- ferences of various degrees and forms. It appears from observation that the tide coming up the British Channel turns off to the Dutch side of the German Ocean, while the tide coming from the north- ward is flowing on the coast of England in the opposite direction. On the coast of Jutland it appears that the tides are almost en- tirely obliterated by interference. A remarkable fact exhibited by the accurate tide observations of 1835, is the great retardation of the tidal wave produced by the shores along which it is propagated. In some places the cotidal line instead of being inclined to the coast at a considerable angle is almost parallel to it ; and so it happens that while it is high water at two promontories bounding a bay at a certain time, it will be high water considerably later in the bay itself. Thus in the British Channel the 10 o'clock cotidal line runs from the eastern shore of the Isle of Wight, touching Beachy Head, Dungeness, the headlands between Dover and Ramsgate, and extends into the mid-channel off the North Foreland, while on the other side it is pretty nearly parallel to the French coast, touching Cape Blanc Nez, and the pro- montory of St. Valery westward of Dieppe. Hence, it is high water at Brighton later than at Beachy Head, at Folkstone later than at Dover, at Dieppe and Boulogne later than at Calais. The same effect is exhibited in numerous instances as the tidal wave travels northward along the coasts of America and Spain. At the end of the lecture the lecturer announced his intention of taking the figure of the earth as the subject of his next course, which will commence on the 4th day of next term. May 26. ON THE INFLUENCE OF HEAT, ETC ON THE CIRCULATION OF THE CHARA. M. Dutrochet read a paper before the Royal Academy of Sciences at Paris, on the circulation of the Chara ; giving an account of his experiments, showing the influence of temperature and mechanical irritation ; and the action of salts, acids, alkalis, narcotics and alcohol upon the circulation of the Ghara flexilis. 458 Intelligence and Miscellaneous Articles, 1st. Influence of temperature. — The circulation exists at the freezing point of water, but is slow. If the water in which the plant is placed be gradually heated, the circulation is accelerated as the tempera- ture increases ; at Qb° to QQ° Fahrenheit it becomes very rapid. It then diminishes, and at 80° it is very much slackened. If the tem- perature of 80° is continued the circulation after some time increases in quickness and soon becomes very rapid. If the temperature be then increased first to 94° and then to 104°, the same effect takes place, that is, the circulation after a diminution in quickness is by degrees accelerated; at 11 3° the circulation is stopped, and does not return. It may be observed therefore that the plant which has been exposed to a temperature below 113° first experiences a torpor, but that this torpor disappears by degrees. Whenever the plant is submitted to a sudden change of temperature of about 77° the rotary motion is completely stopped, but begins again some time afterwards. In ge- nerad a depression of temperature diminishes the quickness of the circulation, while the elevation of temperature, provided it does not exceed certain limits, augments it ; beyond that temperature a slack- ening takes place. Cold produces the same phsenomena : it tends to slacken the circulation, but the vital reaction restores to this cir- culation a quickness which is far from attaining that which it ac- quires under the influence of the action of increase of tempera- ture. 2nd. — Influence of Light. — Light only acts upon the circulation of Chara in its quality of agent to determine its chemical actions of nutrition and respiration ; but in regard to its action upon the exist- ence, and upon the quickness of the circulation, it has no influence ; the temperature being the same, there is no difference in the quick- ness of the circulation either during the day or the night. 3rd. Influence of mechanical irritation. — Compression by means of ligatures has a primitive and direct effect, producing a suspension, or simply a diminution of the motive action of the circulating fluid ; but this action is soon re-established by the vital reaction. Incisions produce the same effect : if the verticillated leaves are cut, situated on the two opposite joints of a stem, the circulation in the central tube is stopped, and does not begin again for some minutes. Punc- tures produce also the same effects, provided they do not penetrate into the cavity of the central tube ; in this case the circulation is en- tirely stopped. 4th. Influence of chemical agents. — A stem of Chara placed in water containing one-thousandth part of its weight of caustic potash or soda in solution stops the circulation after two or three minutes, without return. With a solution containing but one two-thousandth of alkali, the circulation at the expiration of five minutes becomes extremely slow ; five minutes afterwards reaction begins, and the movement becomes very rapid. After 25 minutes the circulation again becomes very slow, and at the end of 35 minutes it entirely ceases, without returning. Lime water destroys the circulation in two or three minutes. A solution containing 50 parts of crystallized Intelligence and Miscellaneous Articles, 459 tartaric acid entirely destroys it in ten or twelve minutes. If the solution contains only one part of tartaric acid in 1000 water, at the end of three minutes the circulation is very much retarded, but after five minutes it is accelerated ; at the end of three quarters of an hour it is again retarded, and after one hour's immersion it altogether ceases. The circulation is immediately destroyed by water holding ;^th of its weight of marine salts in solution ; the liquid makes a disorderly movement, the range of green globules are dissociated and become confusedly dispersed. In a solution containing g^^th of its weight of marine salt the cir- culation is stopped at the end of four minutes, and slight convulsive movements are manifested ; after eight minutes the circulation is re- established and accelerates gradually, continues for eight days and then definitively ceases. A solution of one part of a watery extract of opium in 144 parts of water destroys the circulation in six minutes. In a solution of one part in 288 parts of water the circulation is sus- pended at the end of eight minutes, but ceasing for ten minutes, it begins again and becomes more rapid than it is naturally ; it lasts thus during eighteen hours, then diminishes its quickness, and after twenty two hours it ceases altogether. Water containing -^Q^h. of its volume of alcohol, of 36 degrees strength, considerably diminishes the quick- ness of its circulation at the end of five minutes ; then after ten minutes the movement recommences, accelerated by the vital reaction, and becomes very rapid ; it ceases altogether at the end of 42 hours, after gradually diminishing in quickness. — L'Institut, No. 223, Janu- ary 1838. OXALO-NITRATE OF LEAD. M. Dujardin describes a new double salt, formed of two acids united to one base, which he has obtained, and calls an oxalo- nitrate of lead. It may be formed by dissolving, by the aid of heat, oxalate of lead in weak nitric acid ; the liquid on cooling deposits brilliant white crystals in the form of rhomboidal plates, which appear to be de- rived from the right prism. It remains unchanged upon exposure to the air, is decomposed by heat, which drives off two atoms of water of crystallization, and disengages afterwards a mixture of ni- trous and carbonic acids in red fumes. Water decomposes it, dissolving the nitrate of lead, and leaving the oxalate in the state of a white powder ; but if nitric acid is added and slightly heated the oxalate is redissolved and the double salt reproduced. This salt is composed of one atom of nitrate of lead, one atom of oxalate of lead, and two atoms of water. This is the only double salt of this kind which has been obtained ; the other insoluble oxalates do not form combinations with the corresponding nitrates. Oxalate of manganese is even entirely decomposed by warm nitric acid, whilst oxalate of cerium simply dissolves and crystallizes on cooling ; oxalate of copper is neither dis- solved or decomposed. M. Dujardin also remarks that the double salts described in che- mical treatises, as composed of phosphate and nitrate of lead, cannot 460 Intelligence and Miscellaneous Articles, be obtained by dissolving the phosphate in nitric acid. The cry- stals thus obtained are octahedrons of the nitrate, modified in appear- ance by an excessive elongation of four opposite faces, which [there- fore] might be mistaken for prismatic crystals. — L'Institut, January 1838, No. 223. ACTION OF IRON AT A HIGH TEMPERATURE ON BENZOIC ACID: PRODUCTION OF BENZIN. M. Felix D'Arcet passed the vapour of benzoic acid over red hot iron : by this he obtained a yellowish fluid oil which had an empy- reumatic odour mixed with that of bitter almonds. This oil was rectified on a salt water bath, and left a pitchy resi- due ; the distilled product was very fluid and colourless ; it had a peculiar odour, boiled at 185°Fahr., and congealed at 21^*. By de- composition with oxide of copper it was found to consist of Hydrogen 7-935 Carbon 92*065 100- This liquid is therefore benzin, composed of 6 equivalents of hy- drogen and 12 equivalents of carbon ; its production is attended with the formation of carbonic acid, and supposing hydrated benzoic acid to have been used, the action must have been thus : Hydrogen. Carbon. Oxygen. Benzoic acid 6 14 • 4 Carbonic acid separated 2+4 Benzin obtained .... 6 + 12 When the temperature is too high, then oxide of carbon is ob- tained ; but when it is merely low red, then only carbonic acid is produced. Benzin may also be obtained, according to M. D'Arcet, by distil- ling a mixture of benzoic acid and arsenious acid. — Ann, de Chim. et de Phys., Ixvi. p. 99. ACTION OF IRON AT A HIGH TEMPERATURE ON CAMPHOR. M. F. D'Arcet also passed the vapour of camphor over iron heated to redness ; he obtained in the receiver a very fluid, yellowish, olea- ginous liquor. When subjected to the heat of a salt-water bath no portion of it came over ; but when the temperature was raised to about 293°, a slightly yellow coloured liquid distilled ; it was lighter than water, had a peculiar aromatic odour, not at all resem- bling that of camphor, if the operation was slowly conducted. Analysed by means of oxide of copper, it gave Hydrogen 7*65 Carbon 92*35 100- This product, therefore, like the preceding, is equivalent to a com- pound of 12 hydrogen + 6 carbon, and therefore resembles benzin Intelligence and Miscellaneous Articles, 461 in composition ; but its properties are very different, for it boils at 284° Fahr. instead of 185°. When the operation is conducted at a high temperature, then, besides the above-described product, naph-i thalin is also obtained. — Ibid., p. 110. ON CHLORIDE OF TUNGSTEN. BY M. HENRI ROSE. This chloride was discovered by Woehler, who prepared it by heating oxide of tungsten in a current of chlorine gas. The oxide is then converted into chloride of tungsten, which is volatilized and separately obtained, and tungstic acid, which remains in the appa- ratus after the operation is over. The chloride of tungsten has the property of being decomposed by water into hydrochloric acid and tungstic acid ; and it is this property which induced me to consider it as a chloride of tungsten corresponding in composition with tungstic acid. M. Malaguti supposed that he had confirmed this composition by analysis, having found, by quantitative experiments, that chloride of tungsten, obtained by the action of chlorine on oxide of tungsten, was composed of 47 '4 of tungsten, and 54*89 of chlorine. I obtained the oxide of tungsten, which I used for the preparation of the chloride, from tungstic acid, by means of hydro- gen ; managing the heat so as to avoid the complete reduction of any part of the acid into metal. If a current of dry chlorine gas be passed over the oxide thus prepared, chloride of tungsten is obtained mixed with the red chlo- ride of tungsten which corresponds to the oxide of this metal ; at the upper part of the glass bulb in which the oxide of tungsten is heated, and whilst a current of chlorine was passing through it, there was deposited a substance which could not be volatilized, even by heating the glass bulb as strongly as it could bear the heat. By heating slightly the chloride obtained, it is separated from the red chloride, which is much less volatile. If the chloride be too strongly and suddenly heated, red chloride is formed, and a first residue re- mains, similar to that obtained during the prej)aration of the chlo- ride. These two products are tungstic acid. This decomposition caused a suspicion, that the chloride is not entirely composed of chlorine and tungsten, but that it must contain some oxygen. It will afterwards be seen that it is impossible to obtain the chloride free from all admixture of tungstic acid, by at- tempting to free it from the chloride which accompanies it, with a gentle heat. Lastly, small quantities only of the chloride can be prepared, especially if the glass tubes, which are welted to the bulb in which the oxide of tungsten is heated, are not of suflicient dia- meter ; for the chloride of tungsten formed, which collects near the opening of the tube, in the bulb heated by the spirit-lamp, soon de- posits, by its decomposition, so much tungstic acid as to choke the tube, and causes the bulb to burst. Two hundred and thirty-seven and a half parts of the chloride were dissolved in solution of ammonia, the tungstic acid which was mixed with the chloride remained insoluble ; the solution evaporated nearly to dryness, and the mass dried and calcined gave 198*5 parts of tungstic acid, which corresponds to 66*67 per cent, of tungsten in 402 Inielligeyice and Miscellaneous ArticleL the compound analysed. But as the chloride evidently contains oxygen, besides a small quantity of tungstic acid, formed during the preparation, and principally during the purification of the chloride, upon freeing it from the red chloride which accompanies it, the quantity of tungsten obtained evidently belongs to a combination formed (English equivalents) of 1 atom of tungsten = 100, 1 atom of chlorine = 36, two atoms of oxygen =16. This compound is named by M. Rose tungstate of chloride of tungsten ; he considers it as analogous to the chromate of chloride of chromium ; but he observes that it is a remarkable compound, because tungstic acid, which is one of the most fixed substances, is rendered volatile. When this compound is suddenly heated, it is decomposed into tungstic acid, red chloride of tungsten, and chlo- rine. The tungstic acid is deposited in the state of a bright yellow mass, which has sometimes a greenish tint. The apparent sublimate which is formed in the upper part of the glass bulb when strongly heated, arises from the partial decomposition of the tungstate of chloride of tungsten, which is then deposited at the moment of the action of the chlorine on the oxide of tungsten. This tungstic acid is very difficultly soluble, or rather, it is insoluble in ammonia. It is possible that the tungstic acid which remains insoluble in the solution of ammonia, when the volatile compound of chlorine is dis- solved in it, derives this property and its origin from a decomposition occasioned by a high temperature. Oxide of tungsten was prepared by M. Rose by heating a mix- ture of tungstate of soda and hydrochlorate of ammonia. This oxide when subjected to the action of chlorine, furnished a greater quantity of red chloride than the oxide obtained by reduction with hydrogen, probably because it contained metallic tungsten. As it was necessary to heat this tungstate of chloride of tungsten for a longer time than that obtained by the process above described, in order to free it from the red chloride, it contained a greater admix- ture of tungstic acid; it amounting to 68*92 per cent, instead of 66*67, as already noticed. — Ann. de Chim. et de Phys., vol. Ixvi. p. 13. FALL OF METEORIC STONES IN BRAZIL. On the 11th of December, 1836, about half past 11 o'clock in the evening, with a clear sky and a south-west wind, a meteor of un- common size and brilliancy appeared over the village of Macao, at the entrance of the river Assu ; it immediately burst with a loud crackling noise, and a shower of stones fell within a circle of 10 leagues. They came into several houses and buried themselves some feet deep in the sand, but they did not occasion any further damage than killing and wounding a few oxen. The weight of those picked up varied from 1 to 80 pounds. Specimens which have been sent to the Parisian Academy are to be analysed by Berthier. — Compt. Rend. torn. v. p. 211. — PoggendorfF *s Annalen, No. 12. 1837. ON THE ADULTERATION OF CARMINE. BY C. G. EHRENBERG. There occurs in commerce a kind of very fine coloured and very expensive carmine in the form of cakes, which owes its fine colour to Meteorological Observations. 463 an adulteration. Upon being made use of for ordinary painting no dif- ference has been observed, but by the microscope it may be discovered that half of it consists of starch (wheat starch) which imparts to the finely divided carmine a clear ground and a brilliancy highly increa- sing the appearance of the colour. When such carmine is mixed with much water, it diffuses itself throughout, and is for a long time sus- pended ; but upon pouring off the water a white sediment remains similar to white lead. This sediment is starch. Besides this distinct form and size of an amilaceous body when it is examined by its reac- tion upon tincture of sodium, it produces the well-known blue colour. This sediment when heated with water forms a paste. The addition of white lead is detected by its weight, but the addition of starch is not so easily discovered ; by means of the microscope the adulteration may be with certainty recognised, and confirmed by chemical ex- amination. It may be perhaps interesting for the artist to know that few colours of this description mixed with an organic body, al- though generally pretty permanent, yet in a damp atmosphere are very liable to decomposition. In regird to its covering properties starch differs considerably from white lead. It covers less on ac- count of its transparency. — PoggendorfF's Annalen, No. 12. 1837. METEOROLGICAL OBSERVATIONS FOR MARCH 1838. CUswick. — March 1, 2. Rain. 3. Fine : rain. 4. Rain : foggy. 5. Overcast. 6. Clear: cloudy : clear at night. 7,8. Fine. 9. Frosty: fine. 10 — 12. Very fine. 13. Rain. 14. Hazy: fine. 15. Fine. 16. Fine: stormy showers at night. 17. Clear and cold: showery. 18. Cloudy and fine. 19. Drizzly. 20. Boisterous, with showers. 21. Clear, cold and dry. 22. Hazy: rain. 23. Bleak and cold, with slight snow- showers. 24. Fine : rain. 25. Fine. 26. Frosty and hazy. 27, 28, Fine. 29. Foggy: very fine. 30. Fine. 31. Hazy and cold. Boston. — March 1, 2. Cloudy : rain early a.m. and p.m. 3. Cloudy. 4. Cloudy : rain a.m. and p. m. 5. Cloudy. 6. Fine : rain early a.m. : hurricane with rain p.m. 7. Fine: stormy with rain p.m. 8—12. Fine. 13. Rain. 14 — 16. Cloudy. 17. Fine: snow early a.m. 18. Fine. 19. Cloudy. 20. Stormy: rain early a.m. 21. Stormy. 22. Cloudy. 23. Snow a.m. : rain p.m. 24—27. Fine. 28. Cloudy. 29. Fine. 30, 31. Cloudy. Applegarth Manse, Dumfriesshire. — March 1. Soft weather: dull and cloudy. 2. Rain : soon ceased. 3. Rain and sleet : cleared in the even- ing. 4. Fair and mild : chill in the evening. 5. Fine and clear : wet in the evening. 6. Storm of wind and rain. 7. Showery, with wind. 8. Clear, but cold: morning frosty: sun shone out. 9. Frosty: cloudy: raw in the evening. 10. Cloudy : wet afternoon. 11. Soft rain. 12, Fine day, but frosty: sun shone out. 13. Fine rain, but soon ceased. 14. Soft and genial shower. 15. Brisk wind and dry: sun shone out. 16. Hail showers: sleet: wind. 17. Showers of snow : high wind. 18. Frosty: clear: sun shone out. 19. Soft: cloudy: watery. 20. Stormy: wind and rain. 21. Dry and cold. 22. Sprinkling of snow : cold : sun shone out. 23. Frosty : slight snow : sun shone out. 24. Frosty : fine day : sun shone out. 25. Fine day: snow on the hills : sun shone. 26. Drizzling day, but cleared and sim shone. 27. Fine spring day : sun shone. 28. Fog in the morning: cleared: sun shone. 29. Fme and clear : sun shone out. 30. Fog : sunshine for half an hour. 31. Dull and cold : sun shone for a little. 11 ^is O TJ< <-5 CO rn rr t«5 C*3 O CO CO C5 CO rf rf CO C^ CO ift ^ ( 89Lvaina •uojsoa JlojAisiqo 1^^ . . Tf . .0053 . . 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""i CO ^ 0< . *J ^ G< . ^ bi) c- §"5 t-* 5 = >»-.>>«;€ "3 3 (U D oTi:' CDCCCDCOCOCOCOCOCD fti ©i ©< o< ©> ft) o< ot 0» xxxxxxxxx [ 503 ] LXXVIII. Observations on Dr. Buckland's Theory of the Ac" tion of the Siphuiicle in the Pearly Nautilus. By Thomas Wright, M.KC.S* A LTHOUGH the valuable memoir by Professor Owen -*^ on the Nautilus pompilius has thrown a new and im- portant light upon the history and organization of siphonife- rous cephalopods, still, however, much remains to be learned of the singular structure of this interesting group of the Mol' lusca. From the announcement made by Professor Owen in his article " Cephalopoda," in the Cyclopaedia of Anatomy and Physiology, I was led to expect that Dr. Buckland's Bridge- water Treatise would contain a satisfactory explanation of the action of the siphuncular apparatus of these mollusks. Whilst I admire the tone, talent, and highly popular style of the Bridgewater essay, still I am of opinion that the learned au- thor's theory of the action of the siphuncle is at variance with the facts revealed by the dissection of the animal. On this sub- ject Dr.Buckland observes: "The last contrivance, which I shall here notice, is that which regulates the ascent and descent of the animal by the mechanism of \he Siphuncle, The use of this organ has never yet been satisfactorily made out; even Mr, Owen's most important Memoir leaves its manner of operation uncertain; but the appearances which it occasionally presents in a fossil state supply evidence, which taken in conjunction with Mr. Owen's representation of its termination in a large sac sur- rounding the heart of the animal, appears sufficient to decide this long-disputed question. If we suppose this sac to contain a pericardial Jluid, the place of which is alternately changed from the pericardium to the siphuncle, we shall find in this shifting fluid an hydraulic balance or adjusting power, causing the shell to sink when the pericardial fluid is forced into the siphuncle, and to become buoyant, whenever this fluid returns to the pericardium. On this hypothesis also the chambers would be continually filled with air alone, the elasticity of which would readily admit of the alternate expansion and con- traction of the siphuncle, in the act of admitting or rejecting the pericardial fluid f." In order to estimate the value of this hypothesis, it is necessary to inquire whether the nautilus spends the greater portion of its existence at the bed of the sea, or navigates the surface of its waters. The few authen- ticated instances where this mollusk has been seen at the sur- face, when compared with the thousands of its shells which * Communicated by the Author. t Bridgewater Treatises, VI. Geology and Mineralogy, vol. i. p. 325. 504« Mr. Wright*s Observations on Dr. BuQkhmVs Theory are annually imported into Europe, affords prima facie evi- dence that the nautilus is an inhabitant of the silent depths of the sea ; but when we inquire whether the organization of the animal sanctions this inference, we discover in its ana- tomy peculiarities of structure to adapt it to such a mode of life, the function of which it is impossible to mistake. The number and rudimentary condition of the cephalic append- ages, the presence of a ligamento-muscular disc analogous to the foot of gasteropods, and adapted as a locomotive instru- ment for creeping along the bottom, the simple structure and pedunculated character of the eyes, the dense calcareous na- ture of the jaws, the structure of the digestive organs, but above all the contents of the stomach, which consisted, according to Owen, of the remains of a species of crab*, constitute an as- semblage of characters which enable us to pronounce the manor of this mollusk to be the bed of the sea, where it preys upon Crustacea and other invertebrata. But the nautilus has been seen occasionally at the surface of the water, and the question naturally arises, what are the conditions necessary to accomplish its ascent and descent ? 1st. That the animal should be capable of rendering itself specifically lighter and heavier than the ambient ele- ment. 2nd. That the mechanism by which this act is accomplished should be under the control of its will. Now, Professor Buckland's theory allows only of a change of place in the adjusting fluid, from the pericardial cavity into the siphuncle, and vice versa \ consequently the specific gravity of the entire aiiimal remains the same. The accom- panying outline f, from Owen's dissections, shows the relative position of the internal organs : a a is the enveloping fleshy mantle dissected off to expose hb^ the branchiae floating in c, the branchial chamber for the reception of the water ; d is the heart with its large vascular canals surrounded by clus- ters of glandular follicles, e e. The capacious pericardium ff is laid open to show its boundary and relation to the cen- tral organs of the circulation ; it is partially divided internally by thin muscular septa, gg. From the posterior wall of this musculo-membranous bag there proceeds a canal, or siphuncle, 5 5, destined to traverse all the chambers of the shell: the arrow shows the direction of this aquiferous tube. Anteriorly the pericardium communicates • Art. Cephalopoda^ Cyclopaedia of Anatomy, p. 531. f For splendid figures of the animal and shell o^ the Nautilus pmnpiiiusy consult Dr. Buckland's 31st and 34th plates; also Prof, Owen's invaluable memoir. of the Action of the Siphtincle in the Pearly Nautilus, 505 with the branchial chamber c, by two apertures h h, through each of which a bristle is passed to indicate the channels ol conimunication. From this arrangement it is evident that the pericardial bag has three openings, one behind which conducts the fluid into the siphon, and two before which open into the branchial chamber, into which the sea water is constantly flowing to bathe the respiratory organs. With this mechanism before me, I humbly submit whether it is not a reasonable inference to suppose that the sea water alone is the ballast by which the nautilus is retained at the bottom^ and its ejection the means by which the animal is enabled to rise to the surface at pleasure. Thus by relaxing the anterior orifices, h //, that commu- nicate with the common branchial chamber, the water would flow into the pericardial sac, and from thence into the si- phon 5: during this distended condition of the apparatus the animal and shell would be specifically heavier, and the nautilus, in obedience to a prescribed law, would remain at the bottom without any muscular effort on the part of the 506 Mr. Wright's Observations on Dr. Buckland's Theory animal to retain itself in that situation. Let us suppose that it is the will of the animal to rise to the surface; by calling into action the muscular layers of the pericardium, its watery con- tents would be ejected through the two orifices h /i, a partial vacuum would be thus produced, the remaining portion of the fluid which filled the siph uncle would flow into that ca- vity, and from thence be ejected from the body : it is clear, therefore, that the nautilus would be thus rendered specifically lighter, and would consequently ascend to the surface. When it wishes to descend, it has only to admit the water through the orifices h h, the siphuncular apparatus would be again dis- tended, its gravity increased, and its descent to the bottom accomplished*. This explanation of the action of the siphuncle is applicable to the various modifications of structure observed in the me- chanism of that tube, and avoids the many serious objections which may be reasonably urged against Dr. Buckland'^ hy- pothesis : 1st, We have not sufficient evidence to support the supposi- tion that the air contained in the chambers of the shell undergoes compression ; on the contrary, we find that the Nautilus Sypho from the tertiary strata of Dax pos- sessed a calcareous siphon, which passed through the entire chamber and entered the aperture in the adjoin- ing plate ; and it can be demonstrated that the spirula has a calcareous siphon of an analogous structure ex- tended along the concave side of the shell, so that in these mollusks the siphuncle is a continuous calcareous tube incapable of dilatation, and consequently their ascent and descent in the water was accomplished xmthout those conditions on which Dr. Buckland^s hypothesis rests, i. e. the dilatability of the siphon, and compression of the confined air. 2nd, I have already shown that the nautilus is peculiarly adapted for seeking its prey among the myriads of inver- tebrata that crowd the bed of the sea. Now according to Dr. Buckland, " When the arms and body are ex- panded, the 'fluid remains in the pericardium, and the siphuncle is empty, and collapsed, and surrounded by the portions of air that are permanently confined within each air chamber ; in this state, the specific gravity of the body and shell together is such as to cause the • This explanation was proposed in a course of lectures on Fossil Zoology, which I delivered at the Philosophical Institution of this town, (Cheltenham) a report of which the Editor of the Naturalist has kindly inserted in the last number of his valuable periodical. of the ActioTt of the Siphuncle in the Pearly Nautilus. 507 animal to rise, and be sustained floating at the surface*." If this explanation be correct, the nautilus cannot remain at the bottom unless the siphon is distended by the retreat of the animal into the last chamber of its shell. What a prodigious muscular effort must, therefore, be constantly required to keep the nautilus at the bed of tlie sea ! Again, it may be asked, how is the nautihis to seize its prey at the bottom, seeing the instant its head is protruded to search, and its arms expanded to seize it, " the fluid would be forced back again into the cavity of the pericardium, and thus the shell, diminished as to its specific gravity, would have a tendency to risef"? This theory, therefore, is at variance with the inference obtained from an examination of the organization of the nautilus, that it seeks its prey at the bottom, and is but an occasional visitor at the surface : it is opposed like- wise to a well-known law of the animal oeconomy, that mechanical contrivances are always substituted, where long-continued action is required, to ceconomise the ex- penditure of muscular power; a familiar example is af- forded in the Conchifera^ where an elastic ligament is em- ployed to keep open the valvesof the shell, adductor mus- cles being furnished for the occasional closing of the same. If we test the theory by this principle, we find that to keep the tube distended and the air compressed, in order that the nautilus may remain at the bottom, a constant muscular eflbrt would require to be sustained, in order to overcome the elasticity of the confined air, the expan- sion of which is, according to Dr. Buckland, the power by which the siphuncle is emptied of its aqueous con- tents. The explanation which 1 have ventured to pro- pose is in perfect harmony with the oeconomical law alluded to; for whilst the nautilus is at the bed of the sea, the muscular powers of the pericardium would be in a passive state, just as the adductor muscle of the conchifer is in a state of repose when the valves are kept open by the elastic hinge ; no effort 'would be required to keep the animal in its natural situation ; as in the Conchifera^ so it may be in the nautilus ; an effort of the will shuts the valvesof the former, and the contrac- tion of the pericardium, by ejecting the watery ballast from the siphuncle of the latter, would allow it to change its feeding ground, ascend to a higher stratum of the water, or to its surface if required. * Bridgcwater Treatise, vol. i. p. 329 note. f Ibid., p. 330. 508 Geological Society. 3rd, In reviewing the nature of the peculiar glandular ap- pendages that surround the large vascular canals of the nautihis, I deem it an unfair inference to suppose that they are the organs that secrete the fluid which circu- lates in the siphuncular apparatus, seeing that the same modifications of glandular structure exist in the dibran- chiate cephalopods which are destitute of a siphoni- ferous shell: the true function of these follicular bodies is a physiological problem that yet remains to be solved. Nuneham House, Cheltenham, May 8th, 1838. LXXIX. Proceedings of Learned Societies. GEOLOGICAL SOCIETY. Anniversary Address of the Rev. W. Whewell, M. A., Y.W.'^., President. [Continued from p. 440.] TN attempting a rapid survey of the contributions to geological •*• knowledge which have come under our notice during the past year, I may perhaps be allowed to advert to a distinction of the sub- ject into Descriptive Geology and Geological Dynamics ; the former science having for its object the description of the strata and other features of the earth's surface as they now exist ; and the latter sci- ence being employed in examining and reducing to law the causes which may have produced such phsenomena. We appear to be directed to such a separation of our subject by the present condition of our geological studies, in which we and our predecessors have accumu- lated a vast store of facts of observation, and have laboured with in- tense curiosity, but hitherto with very imperfect success, to extract from these facts a clear and connected knowledge of the history of the earth's changes. Nearly the same was the condition of astronomy at the time of Kepler, when the accumulated observations of twenty cen- turies resisted all the attempts of that ingenious man and his contem- poraries to construct a science of physical astronomy. But though checked by such failures, they were not far from success ; and when for the next succeeding century philosophers had employed themselves in creating a distinct science of Dynamics, the science of physical astronomy, full and complete, made its appearance, as if it were a matter of course ; and thus showed the wisdom of separately cultiva- ting the study of causes, and the classification of facts. DESCRIPTIVE GEOLOGY. If we begin with geological facts, our attention is first drawn to that district on the earth's surface within which the facts have been subjected to a satisfactory comparison and classification, which may be considered, in a general way, as including England, France, Italy, Germany, and Scandinavia. The language which the rocks of these various countries speak has been, in a great measure, reduced to the same geological alphabet. The questions of the determination of Amiiversary of \S3S. Address of the President. 509 any member in one country, or the identification of similar members in two countries, are, for the most part, problems admitting of a defi- nite and exact solution. In countries out of this district, on the other hand, we have not only to explore but to classify. We have to divine their geological alphabet ; — to decipher as well as to read. We have not only to discover of what British rocks the observed ones are the equivalents, but we have to ascertain whether there be an equivalence ; and where this relation vanishes, we have to discover what new resemblances and differences of members are most worthy our notice. The great difference in the nature of the geologist's task in these two cases seems to me to make it desirable to employ the familiar division of Home and Foreign Geology in a wider sense than has hitherto been common, including in the former all that re- gion of Europe which has had its order of strata well identified with our own ; this distinction then I shall employ. 1. Home (North European) Geology. — If we attempt, in this part of our subject, to follow an order of strata, we must begin with the oldest stratified rocks, though they are undoubtedly the most ob- scure ; for the same reason which compels the historian of states to begin with the dim twilight of their savage or heroic times ; namely, because at the other extremity of the series there is no boundary ; since the events of past ages and their records form an unbroken series, leading us to the unfinished occurrences and works of to-day. Going then as far back as the historian of the earth can discern any light, and, for reasons which may hereafter be spoken of, shaping our course by the stratified rocks alone, we should first have to ask what addition has been made during the past year to our acquaintance with those formations which have generally been called transition. And here, gentlemen, many of you well know, that if I had had to address you at a period a little later, I might have hoped to be able to point out, among the labours of our members, some which may be considered as events of primary importance in this part of our know- ledge ; — steps which may be described as a new foundation rather than a mere extension of this portion of European geology ; — a sepa- ration and arrangement of transition rocks, which is likely to become the type and classical model of that part of the geological series, as Smith's arrangement of the oolites became the type of that portion of the strata. I speak of Professor Sedgwick's views on the Cambrian rocks, which occupy the north-west of Wales, and Mr. Murchison's on the Silurian formations which cover the remainder of the princi- pality and the adjacent parts of England. Mr. Murchison's work, which cannot but be one of first-rate value and interest, will, I trust, be in our hands in a few weeks ; and I should grieve to think that Professor Sedgwick will be not only so unjust to his own reputation, but so regardless of the convenience and expectations of geologists, as to withhold from the world much longer the views which his saga- cious and philosophical mind has extracted from the accumulated labour of so many toilsome years, on a subject abandoned to him mainly from its diflficulty and complexity. Turning then to the researches which have been laid before us 510 Geological Society. upon the earlier stratified rocks, I am first led to notice the important memoir of the two gentlemen I have just mentioned, ui)on the struc- ture of North Devonshire*. According to the views of these gentlemen, founded upon an extended examination of the county, this portion of England forms a great trough, having an east and west position, in which a series of culmiferous beds rest at their northern and southern extremities upon older rocks. The plants found in the culmiferous beds are said to be all identical with species which are abundant in the coal-fields of the central counties of England, and of the South Welsh coal basin : and it was at first conceived that these plants differed essentially from the scanty and imperfect remains of vege- tables which are found in the older rocks. More recently, how- ever, the same fossil plants which occur in the culm measures are said to have been detected in the subjacent strata. Before this fact was known, the identity of the fossils and the resemblance of mine- ralogical character seemed irresistibly to prove the culm-bearing beds of Devon to be the same formation with the culm or coal-bearing measures of Pembrokeshire on the opposite side of the Bristol Chan- nel. How far this apparent anomaly admits of explanation, and in what manner it is to be allowed to modify the conclusion previously drawn, we may perhaps most properly consider as questions hereafter to be decided. The rocks which support the culmiferous formation on the north are conceived by Messrs. Sedgwick and Murchison to be a series, of which the last ascending term is probably of the date of the lowest portion of the Silurian system. On the south the culmiferous strata rest partly upon the granite, and partly upon the oldest slate rocks of Devon and Cornwall. The same general view of the nature of the transverse section of Devon, and of the age of the culm, has been presented, perhaps I ought to say adopted, by the authors of two other papers upon the same region which have been brought before us, — Mr. Austen and Mr. Weaver f; and also, at least so far as the section is concerned, by the Rev. D. Williams in a communication made to the British As- sociation in September last. Nor am I aware that it has been dissented from by any one who has examined the county in question since this view was made generally known. Resting on the concurrence of so many able observers, I should conceive, therefore, that we may look upon this view as established, so far as the time which has elapsed al- lows us to use the term. No truths should be termed incontestable till a considerable period has been left for the antagonists to show themselves and to try their force. Although this view has thus so good a claim to acceptance, you are aware, gentlemen, that it is entirely different, both as to the form of the section and the age of the members, from that which was entertained up to the time when these gentlemen turned their atten- tion to the subject. Their opinion respecting Devonshire being [* An abstract of this memoir will be found in Lond. and Edinb. Phil. Mag. vol. xi. p. 311.] ft Abstracts of Mr. Austen's and Mr. Weaver's papers will appear in future Numbers.] Anniversary of \^^S, Address of -the President. 511 adopted, along with the views of the same eminent geologists re- specting Cumberland and North and South Wales, one-third of our geological map of England will require to be touched with a fresh pencil. Nor is this wonderful. It is rather a matter of extraordinary surprise, that when the rest of the geological map of England is again drawn, there are scarcely any but microscopic alterations which require to be made. No higher evidence can be conceived of the vast knowledge and great sagacity of its author. Such modifications we must ever expect to have to make of afirst ap- proximation ; and I should think it a misfortune to our researches if we should attempt to elude this necessity by giving up the key of all our geological knowledge of our country, — the doctrine that there is a fixed order of strata, characterized mainly by their organic fossils. If we have not advanced so far as to prove this, what have we proved ? If our terms do not imply this, what is their meaning ? Is it not true, in our science as in all others, that a technical phraseology is real wealth, because it puts in our hands a vast treasure of foregone generalizations ? And if we evade the difficulties which may occur in the application of this phraseology to new cases, by declaring that our terms are of little importance, is not this to deprive our language of all meaning and all worth .f* Do we not thus refuse to recognise as valuable the tokens which we ourselves circulate, and plainly de- clare ourselves bankrupts in knowledge } When certain strata of Devon have thus been identified with the coal measures of other re- gions, can we still term them grauwacke } Either this term implies members having a definite place in our series of strata, or it does not. If it do, it is certain that these strata have not that place. If it do not, it conveys no geological knowledge at all. But if it be used to imply a rejection of such series, it involves a denial of all geological knowledge hitherto asserted concerning the older rocks of this county. The transition downwards from the culmiferous beds of Devon to the older strata on which they rest, is, according to almost all who have studied the subject, wrapt in great obscurity. In this obscurity, if it be true that the fossil plants of the culm measures are found also in the subjacent rocks, there is nothing which need make us mistrust the clear and positive part of our knowledge. And even if this be so, it will not be the less necessary to separate the culmiferous from the subjacent Silurian and Cambrian systems, by a different name in our lists, and by a different colour in our geological maps, if they are to represent the present state of our information. The interest of this question has induced me to dwell upon it longer than I had intended, and I must on that account be very brief in my notice of many other communications. I may observe that the very nature of several of these indicates very remarkably the European character which our geology has assumed, since they have for their object the identification of some members of the recognised series of England, and of France, or Germany. Thus Mr. Mur- chison and Mr. Strickland have attempted to show, by the evidence of 512 Geological Society. organic fossils, now for the first time adduced on this point, that the red saliferous marls of Gloucester, Worcester, and Warwick shires, with an included bed of sandstone, represent the keuper or marnes Iri- shes of Germany; and that the underlying sandstone of Ombersly, Bromsgrove, and Warwick is part of the hunter sandstein or gres bigarr^ of foreign geologists. They are thus led to conclude that though the muschelkalk.which intervenes between these formations in Germany, is absent in the new red system of England, and of a large part of France, its other members may be identified over the whole of the north of Europe*. Proceeding from the new red to the oolite system, we have a me- moir from Mr. Pratt containing an examination of the geological cha- racter of the coast of Normandy, which necessarily implies a compari- son of this series of rocks with those of England. The identification is found to be complete, as had already been believed ; but Mr. Pratt has made some alteration in the received doctrines on this subject; for instance, the Caen stone, which is usually considered to repre- sent the great oolite, he finds to resemble in its fossils the inferior oolite. Ascending still, we have to notice Mr. Clarke's elaborate geological survey of Suffolk, which, of course, refers entirely to the chalk and overlying beds. With regard to the crag of this district, I may re- mark that M. Desnoyers, in a communication made to the Geological Society of France, has endeavoured to identify this formation with. the Faluns of the Touraine. M. Deshayes had referred the latter to the Miocene, and the crag to the Pliocene formations of Mr. Lyell. The point is one of great interest, since it involves the question of the value and right mode of application of the test of the relative number of recent species, on which Mr. Lyell's classification, or at least his nomenclature, is founded. I conceive that in a matter of arrangement any arbitrary numerical character must lead to viola- tions of nature's classifications ; and can only be considered as an ar- tificial method, to be used provisionally till some more genuine prin- ciple of order is discovered! . Mr. Clarke, in his survey, has noted as one division of the diluvium of his district, a clay of a yellowish or bluish hue, containing rolled pieces of chalk. This deposit is of great extent and thickness in East Anglia and the neighbouring parts J; and is worth notice, since this deposit is one main cause of the geological confusion and obscurity in ■which that region is involved. In the neighbourhood of Cambridge this diluvial deposit is called the hrown clay ; and I can state, from my own experience, that the recognition of it as a separate bed at once rendered the stratification clear, where it had long been unin- telligible. [* See Lond. and Edinb. Phil. Mag., vol. ix. p. 318.] [t An abstract of Mr. Clarke's paper was given in Lond. and Edinb. Phil. Mag. vol. xi. p. 110 : see also the papers referred to in note * p. 114 of the same volume, and Mr. Charlesworth's remarks on the subject in his Magazine of Natural History, vol. ii. p. 117.] [X See Mr. Rose's paper in Lond. and Edinb. Phil. Mag., vol. viii. p. 28. Anniversary o/* 1 8 3 8 . Address of the President. 5 1 3 Before quitting our stratified rocks, I may notice thie commu- nications respecting some of their fossils which we have received, particularly that of Mr. Williamson on the fossil fishes of the Lan- cashire coal field, and the establishment of the new genus Tropaeum, separated from the Hamites of the green sand by Mr. Sowerby. In attempting to pursue a stratigraphical order, we are compelled to reserve for a separate head the notice of unstratified rocks, since their age and history are only known by the mode in which they in- terrupt and disturb the rest of the series. We have not had many communications respecting European rocks of this character ; but we cannot but be struck by the subversion of ancient ideas which result from the investigations of Messrs. Murchison and Sedgwick. They have shown that the granite of Dartmoor, and consequently that of Cornwall, formerly considered as one of the earliest monuments of the primeval ages of the earth's history, is posterior to the deposit of the culm measures. Advancing to newer phsenomena, we find the evidences of change still unexhausted. We cannot but reflect how familiar those views of the elevation and depression of portions of the earth's surface are become, which were at first considered so strange and startling. This is remarkably shown by the number of communications concerning raised beaches which we have recently received. When we visit places where these occur, and look at the winding shore, where the sea line is faithfully followed or distantly imitated by terraces, sands and peb- bles a little above it, we wonder that v:e should so long have been blind to this kind of evidence. Such raised beaches have been de- scribed during the past year, by Mr. Prestwich, as occurring in the Murray Frith ; by Mr. Austen, in the valley of the Axe, the Exe, and the Otter. Dr. Forchammer has given us the evidence of recent elevation in the island of Bornholm ; Mr. Trevelyan has given us similar evidence for the coast of Jutland, and the islands of Guernsey and Jersey *. Mr. Morris's paper, describing a series of dislocations in the chalk cliffs to the south of Ramsgate, marked by shifts in a bed of tabular flint, may perhaps be considered as also affording evidence of violent elevation. But since a small derangement of the conditions of sup- port of any stratum might occasion dislocations of the scale of those here described, it would probably be hazardous to consider them as otherwise than local accidents. Among descriptions of the most recent geological phsenomena, I must notice Mr. Clarke's paper on certain peat marshes and sub- marine forests, which occur near Poole in Dorsetshire ; and in his investigation of the causes which have produced the results now visible, we may see by how easy a gradation descriptive geology passes into the other portion of the subject, the study of the processes by which change is produced. Finally, in concluding this survey of our descriptive home geology, I notice, with great pleasure, Mr. Burr's communication of his notes on the geology of the line of the proposed Birmingham and Glou- [• See our present vohime, p. 284.] Phit, Mag. S. 3. Vol. 12. No. 77. June 1838. 2 U 514 Geological Society, cester Railway. In a country like this, in which the order and boundaries of the strata are, for the most part, well ascertained, an additional accuracy of measurement, of great value to us, may be supplied by the operations of civil engineers employed on canals, roads, and the like works. With this persuasion, and acting with the advice of the Council, I wrote letters to a great number of engi- neers, begging them to communicate to us the levels and sections which they might obtain in the course of their professional employ- ments; and I am happy to see so excellent an example as Mr. Burr's paper supplies, of the advantage which may be derived from mate- rials of this class. 2. Foreign (South European and Trans-European) Geology, — In pro- ceeding beyond the Alps, and still more as we advance beyond the shores of Europe, we can no longer, so far at least as geo- logists have hitherto discovered, trace that remarkable correspond- ence of the strata of different countries which we can study so successfully in our home circuit. With the mountain masses of those more distant regions we are, it would seem, hardly author- ised as yet in making any more detailed distinctions than the general one of secondary and tertiary strata; the latter including the strata in which we trace an approach to the existing species of animals, and the former implying a general comparison with our chalk, oolites, and lower strata. Perhaps we may further distinguish in most countries which have been visited, a great mass of transition slates ; but the establishment of such divisions must be the business of geological observers. We have had several valuable additions to this portion of our know- ledge, including, as we must do, Greece and its islands in this foreign district. That the Apennine limestone is the predominant mass of the Morea, had been made known by the researches of MM. Boblaye and Virlet. Mr. Strickland and Mr. Hamilton have told us that the same rock forms a large mass of the island of Zante and other islands in that sea, and of the neighbourhood of Smyrna. They find also tertiary beds, as on the south side of the bay of Smyrna ; on the east side of the island of Zante ; and at Lixouri in Cephalonia, where the tertiary beds are remarkable for the number and beauty of their fossils, some of which have been identified with species existing in the Mediterranean*. Dr. Bell, who travelled from Teheran to the shores of the Caspian, has given us an account of the rocks which he observed in Mazanderan. From the statements made by him, we are led to believe, that a more continued and detailed observation of the country would give the true geological order of the deposits in this region; which might then, perhaps, serve as a connecting link between western Asia and Indiaf- It is among the favourable omens for the geology of India, of which we now see many, that a temperate, spirit of generalization has recently been applied to the examination of her soil ; a spirit [* See present vol. p. 209.] ft Notices of Dr. Bell's paper, and of others referred to by the President, will appear in future numbers.] I A7imversaty of IS3S. Address of the President, 515 which contents itself with such a general reference of the foreign to the home strata as we have described, till by its own labours it has earned the right of asserting some closer correspondence. If to deny the value of our geological terms within the home district, where they mark an order which has been repeatedly verified, would be a suicidal scepticism in geologists, there would be a rashness and levity no less fatsd in applying them to distant regions where no order has yet been ascertained. Captain Grant in his account of Cutch, and Mr. Malcolmson in his description of a large portion of the Indian peninsula, have not ventured to call the strata which they have examined by the names which describe European formations. We may trust that, hereafter, the admirable activity and resource which our countrymen display in that wonderful appendage of our empire, will enable them to com- municate to us a genuine Indian arrangement of secondary strata. In the mean time, Mr. Malcolmson has most laudably employed him- self in determining the age of the wide-spread igneous rocks of the peninsula of India, with reference to the contiguous strata*. And Dr. McCleland, who was associated with Mr. Griffith in the scientific deputation sent under Dr. Wallich into Upper Asam, has, among other geological observations, noted a raised bed, at 1500 feet above the sea level, in which none of the species are identical with those of the Bay of Bengal on the one hand, or the secondary strata on the north of the Himalaya on the other ; but in which a resemblance was at once recognised with the species of the Paris basin. This resemblance between the extinct animal population of regions so remote from each other, is in itself remarkable enough. It is still more curious to observe, that the same coincidence of the ancient animals of France and India has recently been detected in another case ; and what makes the circumstance stiU more remarkable is, that the animal was not only new in both countries as a fossil genus, but involved a transgression of the supposed boundaries of fossil forms. Not only had no human bones been found in genuine strata, but as it had been generally held, no traces of those creatures which most nearly imitate the human form. This rule now no longer holds good ; for during the past year the bones of monkeys have been dis- covered both at Sansan, in France, in the Sewalik Hills in the north of Hindostanf, and more recently under the city of Calcutta. That this is a highly interesting and important discovery, no one who attends to the signification of geological speculations can doubt. I do not know if there are any persons who lament, or any who exult, that this discovery tends to obliterate the boundary between the present condition of the earth, tenanted by man, and the former stages through which it has passed. For my own part I can see no such tendency. I have no belief that geology will ever be able to point to the commencement of the present order of things, as a pro- blem which she can solve, if she is allowed to make the attempt. The gradation in form between man and other animals, a gradation which we all recognise, and which, therefore, need not startle us because [* See present vol. p. 286.] [f See vol. xi. p. 33, and 208.] 2 U 2 516 Geological Society, it is presented under a new aspect, is but a slight, and, as appears to me, unimportant feature, in looking at the great subject of man's ori- gin. Even if we had no Divine record to guide us, it would be most unphilosophical to attempt to trace back the history of man "without taking into account the most remarkable facts in his nature : the facts of civilization, art, government, writing, speech — his tra- ditions— his internal wants — his intellectual, moral, and religious constitution. If we will look backwards, we must look at all these things as evidences of the origin and end of man's being. When we do thus comprehend in our view the whole of the case, it is im- possible for us, as I have elsewhere said, to arrive at an origin homogeneous with the present state of things ; and on such a sub- ject the geologist may be well content to close his own volume, and open one which has man's moral and religious nature for its subject. In order to complete the notice of the contributions to foreign geo- logy, I must mention Mr. Roy's account of Upper Canada : in which country he conceives that he has detected terraces which exhibit the beaches of the lakes when the level of their surface was more elevated than they are at present*. I must refer also to Mr. BoUaert's paper on alluvial accumulations containing large masses of silver ore in Peru. And, finally, I have to direct your attention to the very curious information respecting the geology of South America, which we have received from Mr. Darwin. In a communication made to us, he gave a very striking view of the structure of a large portion of that continent ; and, as I have already had occasion to observe, he has brought to this country the remains of various fossil animals of entirely new kinds, of exceeding interest to the zoologist as well as the geologist. I need only remind you of the gigantic mammifer which has been reconstructed in idea by Mr. Owen, upon the evidence of a fossil skull, and has been named by him the Toxodon Platensisf. This animal, although a Rodent, accord- ing to its dental characters, in other respects manifests an affinity to the Pachyderms ; and also to the Dinotherium, and to the cetaceous order. Many other fossil animals have been discovered in South America ; and all, from their magnitude, fitted to excite our wonder, when we compare the diminutive size of the present races of animals which inhabit that country. The animal remains found by Mr. Darwin comprise, besides the Toxodon, which extraordinary animal was as large as a hippopotamus, — (2, 3, 4, 5, 6.) the Megatherium, and four or five other large Edentata; — (7.) an immense Mastodon ; — (8.) the Horse ; — (9.) an animal larger than a horse, and of very singular character, of which a fragment of the head has been found ; — (10, 11, 12.') parts of Rodents, one of considerable size ; — (13.) a Llama, or Guanaco, fully as large as the Camel. But I should very ill convey my impression of the great value of the researches of Mr. Darwin, by any enumeration of special points of geology or palaeontology on which they have thrown light. Look- [* See vol. xi. p. 201.] [f See vol. xi. p. 205.] Anniversary o/'lSSB. Address of the President. 517 itig at the general mass of his results, the account of which he has been kind enough to place in my hands, I cannot help considering his voyage round the world as one of the most important events for geology which has occurred for many years. We may think our- selves fortunate that Capt. Fitz Roy, who conducted the expedition, was led, by his enlightened zeal for science, to take out a naturalist with him. And we have further reason to rejoice that this lot fell to a gentleman like Mr. Darwin, who possessed the genuine spirit and zeal, as well as knowledge of a naturalist ; who had pursued the studies which fitted him for this employment, under the friendly guidance of Dr. Grant at Edinburgh, and Professor Henslow and Professor Sedgwick at Cambridge; and whose powers of reason and application had been braced and disciplined by the other stu- dies of the University of which the latter two gentlemen are such distinguished ornaments. But some of the principal of these re- sults may be most conveniently mentioned, when we pass from mere descriptive geology, to that other division of the subject which I have termed Geological Dynamics. And this I now proceed to do. GEOLOGICAL DYNAMICS. This term is intended to express generally the science, so far as we can frame a science, of the causes of change by which geological phsenomena have been produced. Without here speaking of any classification of such changes, I may observe that the gradual eleva- tion and depression, through long ages, of large portions of the earth's crust, is a proximate cause by which such phsenomena have been explained : and this class of events, its evidence, extent, and consequence, is brought before our view by Mr. Darwin's investi- gations, with a clearness and force which has, I think 1 may say, filled all of us with admiration. I may refer especially to his views respecting the history of coral isles. Those vast tracts of the Pacific which contain, along with small portions of scattered land, innumer- able long reefs and small circles of coral, had hitherto been full of problems, of which no satisfactory solution could be found. For how could we explain the strange forms of these reefs ; their long and winding lines ; their parallelism to the shores ? and by what means did the animals, which can only work near the surface, build up a fabric which has its foundations in the deepest abysses of ocean ? To these questions Mr. Darwin replies, that all these circumstances, the linear or annular form, their reference to the boundary of the land, the clusters of little islands occupying so small a portion of the sea, and, above all, the existence of the solid coral at the bottom of deep seas, point out to us that the bottom of the sea has descended slowly and gradually, carrying with it both land and corals ; while the ani- mals of the latter are constantly employed in building to the surface, and thus mark the shores of submerged lands, of which the summits may or may not remain extant above the waters. I need not here further state Mr. Darwin's views, or explain how corals, which when the level is permanent fringe the shore to the depth of twenty fathoms, as the land gradually sinks, become successively encircling reefs at a distance from the shcre ; or barrier reefs at a still greater distance 518 Geological Society. and depth ; or when the circuit is small, lagoon islands: — how, again, the same corals, when the land rises, are carried into elevated situa- tions, where they remain as evidences of the elevation. We have had placed before us the map, in which Mr. Darwin has, upon evi- dence of this kind, divided the surface of the Southern Pacific and Indian oceans into vast bands of alternate elevation and depression ; and we have seen the remarkable confirmation of his views in the observation that active volcanos occur only in the areas of ele- vation. Guided by the principles which he learned from my distin- guished predecessor in this chair, Mr. Darwin has presented this subject under an aspect which cannot but have the most powerful influence on the speculations concerning the history of our globe, to which you, gentlemen, may hereafter be led. I might say the same of the large and philosophical views which you will find illustrated in his work, on the laws of change of climate, of diffusion, duration and extinction of species, and other great problems of our science which this voyage has suggested. I know that I only express your feeling when I say, that we look with impatience to the period when this portion of the results of Captain Fitz Roy's voyage shaU be pub- lished, as the scientific world in general looks eagerly for the whole record of that important expedition. And I cannot omit this occasion of mentioning with great gratifi- cation, the liberal assistance which the Government of this country have lent to the publication of the discoveries in natural history which Mr. Darwin's voyage has produced. The new animals which he has to make known to the world will thus come before the public de- scribed by the most eminent naturalists, and represented in a manner worthy of the subject and of the nation. I am sure that I may ex- press the gratitude of the scientific world, as well as my own, for this enlightened and judicious measure. . I may here notice Mr. Darwin's opinion, so ably exposed in a paper read before us, that the change by which a variety of materials thrown on the earth's surface become vegetable mould, is produced by the digestive process of the common earth worm*. I will here also advert to Mr. Fox's paper on the process by which mineral veins have been filled up. This he conceives might be pro- duced by the circulation or ascension of currents of heated water from the deeper parts of the original fissures. The discovery of the causes of the formation and filling of metallic veins, one of the earliest subjects of geological speculation, will remain probably as a problem for its later stages, when our insight into the laws of slow chemical changes is far clearer than it is at the present day. If, from these proximate causes of change of which I have spoken, we proceed to those ulterior causes by which such events as these are produced; — to the subterraneous machinery by which islands and continents appear and vanish in the great drama of the world's physical history ; — we have before us questions still more obscure, but questions which we must ask and answer in order to entitle our- selves to look with any hope towards geological theory. Of late [* See present vol. p. 89.] Anniversary o/' 1 8 38 . Address of the President, 519 years an opinion has taken root among us, that the dynamics of geology must invoke the aid of mathematical reasoning and calcu- lation, as the dynamics of astronomy did, at the turning point of its splendid career. Nor can we hesitate to accept this opinion, and to look forwards to the mathematical cultivation of physical geology, as one of the destined stages of our progress towards truth. But we must remember, that in order to pursue this path with advantage, we have, in every instance, two steps to make, each of which demands great sagacity, and may require much time and labour. These two steps are, to propose the proper problem, and to solve it. Last year an important example of this kind was brought under your notice by my predecessor. The supposition that there are, beneath the crust of the terrestrial globe, liquid or semiliquid masses which exert a pressure upwards, leads to the inquiry what phsenomena of fissure, disruption, and dislocation, this subterraneous strain would produce. The answer to this inquiry must be given by mathematical reasoning from mechanical principles; and Mr. Hopkins, who pro- posed, and to a considerable extent solved this problem, has put forth a set of results, with which, so far as they are definite and decisive, it will be highly important to compare the existing phsenomena of disturbed geological districts*. The same assumption, of an incandes- cent mass existing deep below the earth's surface, has led two other distinguished members of our body to another train of speculations ; which, however, though highly interesting, I should be disposed to consider as only the enunciation of a problem, requiring no small amount of mathematical skill for its solution. I speak of the specu- lations of Professor Babbage and Sir John Herschel, concerning the subterraneous oscillations of the isothermal surfaces of great tem- peraturef. They remark that such oscillations will arise, when thick and extensive deposits take place on any parts of the surface of the earth, (as for instance at the bottoms of seas,) because such deposits increase the thickness of the coating over a given subterraneous point ; and thus removing the cooling effect of the surface, bring a high temperature to a place where it did not exist before. The de- posited strata might thus be invaded by violent heat advancing from below ; and there might result both changes of position arising from extension and contraction, and a metamorphic structure in the rocks themselves. It is highly instructing to have this chain of concei- vable effects pointed out to us ; but we may venture to observe, that in order to render the suggestion of permanent use, it will be necessary to express, in some probable numbers, the laws of the result as affected by the conductivity of the earth's mass, the rate and thickness of the de- posit, and other circumstances. Forinstance, we know that a deposit of one thousand feet thick would be quite insufficient to occasion a metamorphic operation in its lower strata. Would then a deposit of ten thousand or of twenty thousand feet call into play such a [* Mr. Hopkins's view of his researches will be found in vol. viii. p. 227. et neq. — Edit.] [t See vol. xi. p. 212. 214 ; also the report of the Society's proceed- ings in our next Number.] 520 Geological Society, process*? To answer questions like these, of which a vast number must at once occur to our minds, we have many experimental data to collect, many intricate calculations to follow out. And it would be easy to point out problems of a still more abstruse kind, in which we no less require aid from the mathematician, before we can proceed in our generalizations. May we not hope to see some fortunate man of genius unveil to us the mechanics of crystalline forces ? And when that is done, can we doubt that we shall have a ray of new light thrown upon those extraordinary phsenomena of slaty cleavage in mountain masses which have lately been brought under our notice ? Or, recollecting the experiments of Sir James Hall, (a striking step in geological dynamics,) may we not hope then to learn how those crystalline forces are stimulated by heat ; and thus follow the meta- morphic process into its innermost recesses ? These and a thousand such questions lie before us ; — tangled and arduous inquiries no doubt, but connected by their common bearing upon one great subject ; — ' a mighty maze, but not without a plan.' And through this maze we must force our way in order to advance towards any sound geological theory. The task is one of labour and difficulty ; but I well know, gentlemen, that you will not shrink from it on that account. Those who aspire to the felicity of knowing the causes of things, must not only trample under foot the fears of a timid unphilosophical spirit, which the poet deems so necessary a preparation, but they must look with a steady eye upon difficulty as well as violence. They must regard the terrors of the volcano and the earthquake, the secret paths by which hot and cold and moist and dry ran into their places, the wildest rush of the fluid mass, the latent powers which give so- lidity to the rock, — as operations of which they have to trace the laws and measure the quantities with mathematical exactness. And though there can be no doubt that the greater part of us shall be more use- fully employed in endeavouring to add to the stores of descriptive geology, than in these abstruse and difficult investigations, yet we must always receive, with great pleasure, any communications con- t lining real advances in the mathematical dynamics of geology, from those whose studies and whose powers enable them to lay an effectual grasp upon these complex and refractory problems. I have but a single word to add in conclusion. This Society has always been an object of my admiration and respect, not only from the importance and range of its scientific objects, the wide and exact knowledge which it accumulates, the philosophical spirit which it calls into play, the boundless prospect of advance which it offers ; but also for the manner in which its meetings and the intercourse of its members have ever been conducted ; the manly vigour of discus- sion, tempered always by mutual respect and by good manners ; the deep interest of all in the prosperity of the Society, to which, whenever the hour, of need comes, private differences of opinion and resent- ments have given way. To be placed for a time at the head of a body which I look upon with such sentiments, I must ever consider as one of the greatest distinctions which can reward any one who gives fais attention to science. I trust, by your assistance and kind sym- [* See p. 533. of the present Number.] Roj/al Astro7wmieal Soeiett/. 52! pathy, gentlemen, I shall be able to preserve the spirit and temper which I so much admire; — to hand that torch to my successor burning as brightly as it has hitherto done. And there is one con- sideration which will make me look with an especial satisfac- tion upon such a result. I have not myself the great honour of being one of the members of the Society who are connected with it by an early interest in its fortunes, and by long participation in its labours. I may consider myself as only belonging to its second generation. Now if there be a critical and a perilous time in the progress of a volun- tary association like ours, it is when its administration passes out of the hands of its founders into those of their successors. It is like that important and trying epoch when the youth quits the paternal roof. I will say however, gentlemen, for myself and for my fellow- officers, some of whom are in the same condition, that our best cares shall not be wanting that the Society may suffer as little as possible by this change. And among our grounds for hope and trust, the main one is this : that though the offices of the Society may be in younger hands, the parental cares of its founders are not withdrawn. We have to discharge our office with the aid and counsel of those ex- cellent persons to whom the prosperity of the Society up to the pre- sent time has been owing. Surrounded by such men, knowing their generous and ready sympathy for the attempts and exertions of their followers and disciples, I feel a cheerful confidence in the future des- tinies of the Geological Society ; and a persuasion that it will not only preserve but extend its influence as a bond of scientific and social union among its members. ROYAL ASTRONOMICAL SOCIETY. March 9, 1838*. — The following communications were read: — I. Immersion of \ Cancri at Moon's dark limb, March 6, 1838. By R. Snow, Esq. Corrected sidereal time, 13^ H'" 54». II. Extract of a letter from Sir John Herschel to the President, giving an account of a remarkable increase of magnitude of the star -q in the constellation Argo, observed by him at the Cape, Decem- ber 16-17, 1837. ** I have just observed a very remarkable phaenomenon, the deve- lopment of which I am watching with much interest. It respects the nebulous star r] in the constellation Argo, No. 1281 of the Catalogue of the Astronomical Society, marked in that catalogue as of the second magnitude. As such, or rather as intermediate between the first and second, as a very large star of the second mag- nitude, or a very small one of the first, I have always hitherto ob- served it, having, in some cases, equgJized it with Fomalhaut ; in others placed it intermediate between a and /3 Crucis, nearly equal with the latter, &c.; nor have I at any time had reason to suppose its magnitude variable. Tonight, however, being at work on my classification of the southern stars in order of their magnitudes, I * Wc shall notice the communications made at previous meetings at an- other oppurtunity. 522 JRoml Astronomical Society. was much astonished to find its magnitude superior, not only to that of Fomalhaut and a Crucis (with which stars it no longer admits of a moment's comparison), but even to that of Aldebaran, Procyon, a Eridani, a Ononis, and little if at all inferior to that of Rigel. *' This was my own judgement, and that of several persons whom I called to my assistance, in the early part of the night, when rj was low and Rigel high in the heavens. At the time I write, they have about equal altitudes, and the comparison is decidedly in favour of rj, which is, in fact (Sirius and Canopus excepted), the most brilliant star now visible ; a Centauri being too low for fair comparison, and veiled with some degree of haze. " This remarkable increase of magnitude has come on very sud- denly, as my attention has frequently of late been drawn to this star in the lower part of its diurnal circle, while watching with some impatience its progress towards the meridian, at a reasonable hour of the night, that I might resume and complete, before my depart- ure hence, a very elaborate monograph of the wonderful nebula which surrounds it. A few evenings before the full moon just passed, in particular, I remember to have noticed it with this view ; and had it then been what it now is, a star of the first class, it could not have passed unremarked. " Whether it be now at its maximum, and about to decrease by insensible degrees ; whether, like Algol, but in a much longer time, it remains as it were dormant through the greater part of its period, and runs through its phases of increase and decrease in a small aliquot portion of the whole ; or whether, lastly, it be on the point of blazing forth with extraordinary splendour, so as possibly to out- shine its brilliant neighbours, a Centauri and Canopus, it is useless to conjecture, and observation will soon determine." III. Value of the Mass of Uranus, deduced from Observations of its Satellites, made at the Royal Observatory of Munich during the year 1837. By Dr. F. Lamont, Director of the Royal Observatory. In the course of the year 1837, a few favourable nights were em- ployed in taldng observations of the satellites of Uranus, with a view of calculating the value of the planet's mass ; and, though the ob- ject has not been satisfactorily attained, owing to the difiiculty of the observations, and the present unfavourable position of the orbits of the satellites, the result is not without interest, as it leads to the conclusion that the true value of the mass of Uranus is considerably smaller than that which is generally adopted. The instrument used in the observations was a refractor con- structed at Munich, having a focal length of 15 feet, and an aper- ture of IQi inches, Paris measure. The fact of its having served to measure the distances of the satellites of Uranus is sufficient evi- dence of its superior power. Dr. Lamont acknowledges, however, that, notwithstanding the great optical power of the telescope, he has not, as yet, been able to discover more than three of the satel- lites, namely, the second, the fourth, and the sixth*. The sixth * The satellites are named in the order of their distances from the planet, so that those which arc here termed the second and fourth, correspond re- Dr. Lamont on the Mass and Satellites of Uranus, 523 was observed only once, and the observation is of consequence omitted, as being of no use in the present inquiry. The measures were obtained by using a parallel wire-micrometer of Fraunhofer's construction, having the wires, not the field, illu- minated. Instead of the lamps usually employed, a light placed at a distance was reflected on the wires by a small mirror. Dr. Lamont remarks, that the use of a mirror is greatly to be preferred to lamps, because, in addition to its being more convenient, it affords in the measurement of faint objects a peculiar advantage, in enabling the observer to direct the illumination to any part of the wires, and with any degree of intensity that may be required. But, however carefully the illumination may be managed, it would be impossible to bisect with a wire any of the satellites of Uranus, and, accordingly. Dr. Lamont had recourse to another method, which he has frequently adopted in similar cases. Placing the fixed wire so as to bisect the disc of the planet, he moved the micrometer until the satellite appeared exactly in the middle of the space be- tween both wires. The measure being repeated on the opposite side of the fixed wire, in order to eliminate the zero point, the diflference of the two readings gave the quadruple distance of the satellite. The table of observations given by the author contains the sidereal time of each observation ; the mean Paris time, including aberration ; the observed angles of position ; the observed distances, and the number of measures taken at each observation. The number of observations of the second satellite was 11, and of the fourth, 15. Although the observations furnish sufficient proof of the elliptic motion of the satellites, any attempt to investigate the elliptic ele- ments from the few data obtained in the present unfavourable situ- ation of the orbits, would be unavailing. Dr. Lamont, therefore, assumes the satellites to move in circular orbits, in a plane having, as computed by Sir W. Herschel, an inclination of lOP 2' to the ecliptic, the longitude of the ascending node being 165° 30'; and on this hypothesis proceeds to compute from the observations the distances and times of revolution of the two satellites. The results of the computation are as follows : Distance. Periodic Time. Second satellite 31"-35 8^705886 Fourth ditto 40 '07 13 ,463263 Having found the distances and periods of revolution, it remains to compute the value of the planet's mass. It is found, however, that the values derived from both satellites exhibit a considerable difference, as might indeed be expected, when it is considered that spectively to t\ie first and second of Sir W. Herschel. [An abstract of Sir John F. W. Herschers investigation of the motions of the same two satel- lites of Uranus, was given in Lond. and Edinb. Phil. Mag^ vol. iv. p. 381. Sir John observes, that he had, at the period of his communication, no evi- dence of the existence of any other satellites of this planet. — Edit,] 524 Royal Astronomical Society* the mean distances are the result of a small number of observations calculated upon the gratuitous supposition of circular orbits. On diminishing the radius of the second satellite by 0''"79, and aug- menting that of the fourth by the same quantity, in order to make the distances accord with the periods of revolution, the value of the mass of Uranus is found = ni^rr-, being less by one-fourth part than that obtained by M. Bouvard, from the perturbations produced by the planet. Dr. Lamont remarks that, in giving this value he is too well aware of the uncertainty of the data on which it rests to attach any particular weight to it; but, though he considers the measures obtained by him in 1837 as being unfit, until combined with fur- ther observations, to give a value of the mass of Uranus that might, with confidence, be employed in the theory of the planetary motion, there is one purpose they will serve at present, namely, to enable us to judge whether a given value of the mass of Uranus can be regarded as probably true or not by its agreement or disagreement with them. Bouvard's value, which is generally adopted, is TtqTo* Computing from this the mean distances of the two satellites, the distance of the planet from the earth being assumed = 19'223, he finds the mean angular distance of the second satellite = 33"*96, and that of the fourth = 45"*42. The difference of these values from those computed from the observations, is + 2"- 61 and + 5"*35. Now, without entering into the theory of probable errors, it will readily be granted, he conceives, on considering the differences of the indi- vidual errors from the mean, and even allowing a probable error for eccentricity, that scarcely an error of 2", much less one exceeding 5", can be attributed to the distances obtained from observation. The supposition of a constant error in the instrument can scarcely be admitted ; for, on measuring distances that had otherwise been determined with precision, no constant error has been found to exist. In conclusion, the author states that he considers it certain that the value of the mass of Uranus, at present used in the theory of the planetary perturbations, ought to be greatly diminished, though the precise proportion in which this should be done, cannot at present be assigned. Considering the difficulty of the observations, and the small number of nights in which measures of so much delicacy can be made, it will not be possible, within the period of several years, to deduce the true value of the planet's mass from the elongations of the satellites. A table of these stars, giving the dates of observation, the desig- nation of the objects, and the apparent right ascension for each Ob- servatory, will be found in the Monthly Notices of the Society for March. IV. Stars observed with the Moon at the Royal Observatories of Greenwich and Edinburgh, and the Observatory of Cambridge, in the months of October, November, and December, 1837. Royal Aitronomical Society, 525 The anonymous star observed (at Greenwich) on October 12, A. S. C. 79. (Piscium, apparent right ascension at Greenwich 0^ 39"» 53«,52 ; at Cambridge 0^ SQ*" 53»,73 ; at Edinburgh 0^ 39™ 53^,30.), has an erroneous right ascension in the Nautical Almanac, derived from an erroneous right ascension in the Astronomical So- ciety's Catalogue. See the Cambridge Observations, 1831. April 13. — ^The following communications were read : — I. On the Correction of the Mean Distance, Eccentricity, Epoch, and Longitude, of the Aphelion of the Orbit of Venus, by Errors of Heliocentric Longitude, derived from the Cambridge Observations of the Years 1833, 1834, and 1835, and the Greenwich Observations of 1836. By the Rev. R. Main. The author states, that being furnished by the Astronomer Royal with his computed errors of heliocentric longitude of the planet Venus, derived from four years' unintermitted observations, he un- dertook to correct the above-mentioned elements by jneans of them . An abstract of the paper appears in the Monthly Notices for April, giving the ultimate results of the investigation as follows : The combined equations are given separately for each year, to the end that any suspected error may be more readily detected, and the solutions given for each year separately. They are as follow : 1833. 1834. 1835. 1836. Za= +0-0000203 -0-C000047 + 0-0000368 +0-0000236 ^e = -0-0000262 -0-0000223 -0-0000280 + 00000186 ae=- 2"-l - 4"-9 - 3"-6 - 4"-l ^TT = -587 -7 -501 -3 + 328 -4 - 67 -3 II. Moon culminating Observations made at Rio Janeiro and Valparaiso in 1836. By Captain F. W. Beechey, R.N. From these observations, compared with the corresponding ob- servations made at Greenwich, Cambridge, Edinburgh, Paris, and the Cape of Good Hope, and with the Nautical Almanac, Captain Beechey has deduced the following results. Longitude of Fort S. Antonio, Valparaiso. . 7P 39' 36"-7 W. Longitude of Anhatomirim, Brazil 43 09 13 '5 W. III. Times of Immersion of the first and second Satellites of Jupiter, observed at Greenwich Hospital Schools, April 9, 1838. By E. Riddle, Esq. See Monthly Notices. IV. Longitude of the Edinburgh Observatory, computed from the corresponding Moon Culminating Observations made at Edin- burgh and Greenwich, from August 24, 1836,« till the end of 1837. By Mr. Riddle. The number of observations is 62, and the mean of the whole, allowing each observation weight proportional to the number of stars observed, gives the longitude =12™ 44*, 7. In the Notices for March 1837, are given the results deduced from all the corresponding observations of the same class, made at the two Observatories under the direction of the present astronomers, before the date of the first in this list. The mean result of these 526 Zoological Society, preceding observations was 12*" 44^,5, differing only ,2^ from the present determination. V. Eclipses of Jupiter's Satellites, observed at Edinburgh. By Professor Henderson. VI. Lunar Occultations observed at Edinburgh. By Professor Henderson. A table of these, giving the date, true sidereal time, object, phsenomena, and remarks, appears in the Monthly Notices. VII. Immersion of 47 Gerninorum at Moon's dark limb, April 1, 1838. By R. Snow, Esq. Corrected sidereal time, 14^ 25'" 4^73. VIII. The President read an extract of a letter from Mr. Hender^ son relative to the remarkable increase of magnitude, in rj Argus, recently noticed by Sir John Herschel, as mentioned at the last meeting of the Society (ante, p. 521.). Mr. Henderson states that the star is not to be found at all in Ptolemy's catalogue, although the bright stars of the Cross and the Centaur, which culminated as low at Alexandria, are inserted in it. From this circumstance he infers that, at this remote period, the star was not very bright. It is not in Bayer's maps ; and in Halley's catalogue it is said to be of the fourth magnitude, which is less than some of the neighbouring stars that in modern times cannot compete with it. It would thus appear that the star has for a long period been increasing in brightness ; and it will be remarkable if it should surpass the brightest at pre- sent known. ZOOLOGICAL SOCIETY. [Continued from p. 451.] March 28, 1837. — Mr. Chambers read a paper upon the habits and geographical distribution of Humming Birds, and exhibited the nest and eggs of the only species {Trochilus coluhris,) which visits the United States, and which is there very commonly bred in confinement. Mr. Chambers adverted to the probability of success if attempts were made to domesticate these birds in this country. A lady residing at Boston informed him that in that city they are readily reared in cages, and she expressed great surprise on hearing that only one instance had occurred of their being domesticated in England, as the climate so nearly corresponds. The first part of a paper was then read by F. Debell Bennett, Esq., corresponding member, on " The Natural History of the Sper- maceti Whale." Mr. Yarrell then brought before the notice of the meeting " A Synopsis of the Fishes of Madeira," by the Rev. R. T. Lowe, Cor- responding Member of the Society. This synopsis includes all the Fishes hitherto found at Madeira, with observations upon many of the species, and the character of such genera and species as are new. The Author has also drawn up a table, showing the com- parative number and distribution of the British, Mediterranean, and Madeiran Fishes. It appears from this, that notwithstanding the uniformity of its shores, both in structure and materials, occasioning a corresponding uniformity in food and shelter, that the number of marine species found at Madeira equals two thirds the amount be- longing to the British seas. Zoological Society. 527 With the exception of the genus Anguilla, the fresh-water species are entirely absent, the physical structure of the island preventing the formation of lakes and pools, and reducing its streams to the cha- racter of rapid rivulets or mountain torrents. A result indicated by the table just referred to, and which Mr. Lowe particularly notices, is, that Madeira possesses as many species in common with Britain as it has with the Mediterranean, and also that there is a variation in the ratio between the marine Acanthopterygians and Malaco- pterygians proportionate to the latitude. In Britain the marine ^caw- thopterygians are to the marine Malacopterygians as one and a quarter to one ; in the Mediterranean, as two and three fifths to one ; while at Madeira the ratio increases to three and a half to one. The Author's remaining observations principally relate to the particular periods of the year, and to the comparative abundance in which certain species are met with. A Notice by Thomas Wharton Jones, Esq., was then read, " On the mode of closure of the gill-apertures in the tadpoles of Batra- chia." Mr. Jones observes, that when the right gill of the tadpole disap- pears, it is not, as is usually supposed, by the closure of the fissure through which it protrudes, but by the extension of the opercular fold on the right side towards that of the left, forming but a single fissure, common to the two branchial cavities, through which the left gill still protrudes. He also remarks that conditions analogous to those which occur during several stages of this process exist in the branchial fissures of the anguilliform genera, Sphagebranchus, Monopterus, and Synhranchus. April 11, 1837. — The reading of Mr. F. De Bell Bennett's paper " On the Natural History of the Spermaceti Whale" was resumed ; an abstract of which is given in No. Hi. of the Proceedings. Mr. Gould then called the attention of the meeting to a new and beautiful species of Ortyx, a native of California, from the collection of the late David Douglas, and characterized it under the name of O. plumifera. He remarked that this genus was first brought before the Society eight or nine years ago by Mr. Vigors, at which time only five spe- cies were known, but since that period the number had been doubled ; and from the remarkable development of the feathers forming the crest in the species then exhibited Mr. Gould anticipates the dis- covery of others, which shall connect Ortyx plumifera with those species in which this character is less prominently shown. In sup- port of this opinion Mr. Gould directed attention to the genera Larus, Trogon and Caprimulgus, which possess certain characters largely developed ; but the degree of development increases gradually from the species in which it is least apparent to those in which it attains its greatest extent. Mr. Gould then exhibited a new species of the genus Podar- gus, from Java, which he proposes to name P. stellatus. Some observations on the Physalia, by George Bennett, Esq., F.L.S., Superintendent of the Australian Museum at Sydney, and 528 Zoological Society* Corresponding Member of the Zoological Society, were then read. Some specimens of Physalia pelagica having been captured by Mr. Bennett while on his voyage to Sydney, he had an opportunity of observing the action of the numerous filamentary bodies attached to the air-bladder of this animal. The longest of these appendages are used by the Physalia for the capture of its prey, and are capable of being coiled up within half an inch of the air bladder, and then darted out with astonishing rapidity to the distance of 12 or 18 feet, twining round and paraly- zing by means of an acid secretion any smidl fish within that di- stance. The food thus seized by the tentacula is rapidly conveyed to the short appendages or tubes, which are furnished with mouths for its reception. These tubes appear to constitute the stomach of the animal, for upon a careful dissection nothing like a common recept- acle for food could be observed, nor could Mr. Bennett detect any communications between them and the air-bladder, to the inferior portion of which they are attached by means of a dense muscular band. After an examination of an immense number of specimens, Mr. Bennett was unable to discover the orifice usually stated to exist at the pointed end of the bladder, nor could he ever succeed in expelling any portion of the contained ■ air without a puncture being previously made. This organ consists of two coats, the outer of which is dense and muscular, readily separating from the inner, which resembles a cellular membrane. The partial escape of air from the bladder did not at all affect the buoyancy, or appear in any way to incommode the Physalia ; and even when it had completely collapsed, the animal still floated on the surface ; upon removing the bladder entirely, the mass of ten- tacula sank to the bottom of the vessel, and though their vitality re- mained, all power of action was entirely destroyed. A letter was then read, addressed to Mr. Gould, from M. Nat- terer, describing a new species of Pteroglossus, from Para in Brazil, which the writer proposes to name P. Gouldii, in commemoration of the valuable contributions which ornithology has derived from the labours of Mr. Gould. April 25, 1837. — A letter was read addressed to N. A. Vigors, Esq., M. P., from Mr. Henry Denny of Leeds, stating that a fine male specimen of the Snowy Owl had been recently captured at Selby in Yorkshire. • Mr. Gray then exhibited the horn of a Deer supposed to come from India, which he considered as characteristic of a new species peculiar for the elongate acute form of the basal branch, which ap- pears to have been depressed, and directed obliquely across the fore- head of the animal. This horn, which had not attained its full period of growth, agreed with that of the Rein Deer, in being palmate, and in having the basal frontlet depressed, in which latter character it is allied to an Indian species called by Mr. Gray Cervus Smithii, known by a drawing belonging to the collection of General Hardwick in the British Museum. Zoological Society, 529 Mr. Gray then adverted to some observations which he had made on a former occasion during a discussion upon the nature of the re- lation existing between the Argonaut shell and the Cephalopod which inhabits it. On that occasion, one argument made use of by him in favour of the parasitic nature of this animal, was, that the nucleus of the Argonaut shell is larger than could be contained within the eggs which often accompany the Ocythoe. He is now disposed to attach less importance to this circumstance, having re- cently observed that the eggs of some moUusca, as the Buccinum undatum, prior to the period of hatching, are eight or ten times as large in diameter as when first deposited. A paper was then read by Thomas Bell, Esq., entitled ** Observa- tions on the genus Galictis, with a description of a new species." Mr. Bell in 1826 laid before the Zoological Club of the Linnaean Society some remarks upon a living female Grison which had been several years in his possession, and he then proposed to consider the species as constituting a new generic type, to which he gave the name of Galictis, but without assigning its distinctive generic cha- racters. Since that period the examination of a specimen in the collection of the Zoological Society, exhibiting a distinct specific dif- ference from the former, but agreeing with it in the more essential particulars, has confirmed the propriety of establishing this genus ; and in the present communication the author points out the charac- ters and affinities of Galictis, and gives a description of the new species under the name of G. Allamandi, M. Allamand having figured a specimen in the fourth edition of BufFon's Natural History, which may perhaps be identical with this second species. In constituting this new genus of Mustelidce, Mr. Bell has been guided solely by the semiplantigrade form of the foot, for in no other important charac- ter does it deviate from the typical genus of that family. A know- ledge of this character led Thunberg to place it among the Ursidcs under the name of Ursus Brasiliensis, to which group it slightly ap- proximates, and in which it may probably be represented by the genus Ratellus. By Desmarest it is arranged in the genus Gulo, and the name Gulo vittatus given to it by that author has been adopted by the Cuviers, and all other subsequent writers, with the exception of Dr. Traill, who in the third volume of the Memoirs of the Werner- ian Society restores it to its proper family, the Mustelidce, but under the erroneous name of Lutra vittata, for it has no nearer affinity to the Otters than any other genus of that family. By Schreber it was placed among the Viverree, under the name of Viverra vittata, and the name has been retained by Gmelin and others. The characters of Galictis, and the description of the two species which at present constitute this genus, are as follows. Fam. MusTELiDiE. Genus Galictis, Bell. Char. Gkn. Denies molares spurii ^• Rostrum breve. Palmcc atque plants nudae subplantigradae. Phil. Mag. S. 3. Vol. 1-2. No. 77. June 1838. 2 X 530 Zoological Society, Ungues breviusculi, curvi, acuti. Corpus elongatum, depressum. Sp. 1. Galictis vittata. G. vertice, collo, dorsoy afque cavdd Jlavescenti-griseis ; rostra guld etpectorefuscescenti-nigris; fascia a f rente usque ad humeros vescenti-albidd ; pilis longis taxis. Sp. 2. Galictis Allamandi. G. vertice, collo, dorse, atque caudd nigricanti-griseis ; partibus infe- rioribus nigris ; fascia a f route usque ad collum utrinque albd ; corpore pilis brevibus adpressis. Habitat. June 27, 1837. — A Letter was read addressed to Mr. Gould, from Mr. lliomas Allis of York, in which the writer remarks that the scle- rotic ring of the great Podargus does not j^resent the slightest ap- pearance of distinct plates, being simply a bony ring ; the first in- stance in which Mr. Allis had observed this peculiarity. A Letter was also read from His Excellency Hamilton Hamilton, Esq., Her Majesty's Minister at Rio, announcing the present of a Chilian Eagle for the Society's Gardens. Mr. Gray exhibited a specimen of a Paradoxurus from the Ma- layan Peninsula, which had been presented to the Museum of the Society by the President, the Earl of Derby, and for which he pro- posed the specific name of Derbianus. Mr. Gray also brought before the notice of the Meeting some Mammalia, which he had lately purchased for the British Museum from a collection made by the late Colonel Cobb in India, among which was an adult specimen of the Once of BuiFon (Hist. Nat.), on which Schreber formed his Felis uncia, which has been regarded by Cuvier, Temminck, and most succeeding authors as a leopard, but which is a distinct species, easily known by the thickness of its fur, the paleness of its colour, the irregular form of the spots, and especially by the great length and thickness of the tail. Mr. Gray observed that a more detailed description of this animal was unne- cessary, as it agreed in all particulars with the young specimen de- scribed by Buflfon. Two new species of Sciuroptera, which agree with the Ame- rican species in colour, but differed from one another in the size, make, and form of the soles of the feet, were described under the spe- cific names oi fimbriata and Turnbulli. A new species of Fox, nearly allied to Vulpes Bengalensis, but evi- dently larger, Mr. Gray designated as Vulpes xanthur a. In describing this species, he remarked, that it had a large gland, covered with rigid brown hair, on the upper part of the base of its tail, very di- stinctly marked ; and that on looking at the tail of the several other species of this genus, as V. Bengalensis, V, vulgaris, V.fulva, and some others, a similar gland was easily recognisable, though it ap- peared to have been hitherto overlooked. Mr. Ogilby afterwards characterized a new species of Gibbon (//y- lobates), which had been presented to the Society many years ago. Li7incean Society. 531 by tlie late General Hardwicke, and hitherto considered as the female of the Hoolock. A specimen of the latter species had been presented to the Society at the same time, and from the same locality ; but their specific identity was sufficiently disproved, not only by the fact of both specimens being of the same sex, and from our being perfectly acquainted with both sexes of the Hoolock, but likewise by the marked difference of colour and external structure exhibited by the two ani- mals. The greater height of the forehead and prominence of the nose in the new species were pointed out as alone sufficient to distinguish it from all the other Gibbons ; whilst its ashy-brown colour and large black whiskers rendered it almost impossible to confound it with the Hoolock, which has fur of a shining black, and a pure white band across the forehead. Mr. Ogilby observed, that we have had two distinct instances of real Apes from the continental parts of India; and referred to various passages of Pliny, in which the Roman natu- ralist professed to describe different races of human beings from the remote provinces of India, whom he relates to have teeth like dogs, to live among trees, and to converse by frightful screams. These distorted accounts Mr. Ogilby conceives to have been founded upon the vague tales brought back by the few Greek and Roman travellers who at that time penetrated beyond the Ganges, and proposed therefore to call the new Gibbon by the name of Hylohates Choro- mandus, the name of one of the supposed tribes of men described by Pliny. The same gentleman afterwards exhibited and described the skin of anew species of Colobus, or four-fingered monkey from Africa; for which he proposed the specific name of Colobus leucomeros, on account of the white colour of the thighs, the rest of the animal being a deep shining black. Dr. Smith exhibited some small Quadrupeds, forming part of the collection obtained during his recent expedition into South Africa. They consisted of some new or rare species belonging to the genera Macroscelides, Chrysochloris, Pteromys, and Otomys. Dr. Smith en- tered into some interesting details respecting their habits, which will be published in his forthcoming work on African Zoology. LINN^AN SOCIETY. Jan. 16, 1838. — Read a Paper on the Structure of Cuscuia euro* pcea. By Charles C. Babington, Esq., M.A., F.L.S. ITie descriptions and figures of this plant given in the various w'orks on our native plants are very imperfect. Mr. Babington's observations on recent specimens gathered in Sussex, in company with Mr. Bower, confirm the statement of Mr. Brown as to the ex- istence of scales in the tube of the corolla, a fact denied both by Sir J. E. Smith and Sir W. Hooker, who, however, appear to have examined dried specimens. These scales are transparent, closely pressed to the corolla, and very minute, so that they are easily over- looked, even in recent specimens, and in dried ones it is scarcely possible to discern them. They are bicuspidate, erect, and situated at the inner base of the filaments, which they partially inclose. Their form and position appear to have been first accurately described 2X2 532 LinncEdn Societi/. by Raymond, as recorded by Romer and Schnltes. Reichenbaeli describes and figures them as palmate, and as situated at the base of the tube, so that it is probable his plant is different from ours, as Mr. Babington suggests. The nature of these scales is not well un- derstood : by most botanists they are regarded as a vorticil of abor- tive stamens, and by Reichenbach as petals ; but their situation always within the stamens, and opposite to them, appears to refute both these opinions. Analogous scales occur in Hydrophyllea:. Feb. 20. — Read a Paper, by John Hogg, Esq., M,A., F,L.S., on the classification of the Amphibia, The author takes a review of the different modes of arrangement that have been proposed for this remarkable class of animals, and he concludes his paper by suggesting a new classification founded upon the organs of respiration, as the result of his investigation. March 6. — Read a description of the Mosses collected in the journey of the late deputation into Upper Assam, in the years 1835 and 1836. By William Griffith, Esq., Assistant Surgeon on the Madras Establishment. Communicated by R. H. Solly, Esq., F.R.S. & L.S. The discovery of the China tea plant in Upper Assam attracted the attention of the Indian government, and accordingly a deputation, consisting of Dr. Wallich, Mr. M'Clelland, and Mr. Griffith, was sent from Calcutta to investigate the subject. The present paper comprises descriptions of the Musci collected in the journey ; but the greater portion of the species, Mr. Griffith states, was gathered in the Khasya Hills, an elevated tract of country, forming part of the eastern frontier of British India. The climate is described to be excessively moist, which will ac- count for the large number of mosses collected in the journey by Mr. Griffith, forming about one eighth of the entire family, 1324 being the amount of species enumerated by Bridel in his Bryologia Uni- versa. The collection contains Sphagnum ohtusifolium, Polytrichum urni- gerum and aloides, Weissia Templetoni, Dicranum scoparium and glau- cum, Bartramia font ana, and several others familiar to the European muscologist ; but the far greater part of the species have not been previously described. March 20. — Read a description of the Mora tree. By Mr. Robert H. Schomburgk. Communicated by George Bentham, Esq., F.L.S. This tree is a native of the forests of British Guiana, where it at- tains a large size, the trunk often exceeding ninety feet in height, with a circumference of upwards of twenty feet. The trunk pro- duces large buttresses at its base, which from their partial decay afterwards become hollow beneath, and form a chamber capable of sheltering several persons standing erect. The tops of these but- tresses, and the trunk itself, are found clothed with innumerable epiphytes, which greatly add to the singularity of the tree. The tree affords timber of excellent quality, being close-grained, strong, tough and durable, and not liable to split. The Mora tree consti- tutes a new genus of the order Leguminosae, belonging to the sub- lloyal histitution, 533 order C^csalpinete, and tribe CassiecB. Mr. Bentham adopts the na- tive name for the genus, and proposes that of excelsa for the species. The genus is nearly related to Tachigalia of Aublet, and Leptolo- hium of Vogel, but differs from both in the woody texture of the pod, which is moreover naturally dehiscent, in the greater regularity of the parts of the flower, and in the sterility of the alternate sta- mina. April 3. — Read a communication on the existence of Stomata in Mosses. In a letter to R. H. Solly, Esq., F.R.S. & L.S. By Wil- liam Valentine, Esq., F.L.S. The discovery of stomata in mosses was reserved for Mr. Valen- tine, an opinion of their absence from that family having univer- sally obtained amongst botanists. It was in Bryum crudum that Mr. Valentine first detected stomata, and of one hundred and three Bri- tish mosses examined by him, seventy-eight were found to possess these organs. Their situation in this family is very remarkable, be- ing confined, with one exception, to the theca, and the thinness of the tissue will readily account for their absence from other parts. The more common form of the stomata in mosses is similar to that generally found amongst phsenogamous plants. Each consists of two oblong reniform cells, with their concave sides opposed to each other. In Funaria hygrometrica they consist of a single cell in the form of a hollow ring, and in five British species of Orthotrichum (diaphanum, pulchellum, rivulare, anomalum, and cupulatum) they have a raised border of projecting cells which form a cavity above the stoma, re- sembling somewhat those of Marchantia and Targionia. ROYAL INSTITUTION. April 27. — Mr. Grainger on the physiology of the spinal cord. May 4. — Mr. Hickson on vocal music as a branch of education. May 11. — Mr. Brayley on the Theory of Volcanos. The subject was introduced by allusion to the important results which have ensued from the recent direction of the minds of mathematicians to the philosophy of geology, and from the application to the theory of geological phsenomena, both of actual mathematical analysis and of general mathematical reasoning. Mr. Hopkins's researches on the mechanical theory of elevation, recently applied by Prof. J. Phillips to exi)lain the structure of parts of the North of England, and the theory of volcanic action dependent on that of the secular varia- tion of the isothermal surfaces within the globe, in which Mr. Bab- bage and Sir John F. W. Herschel have independently concurred, having been cited as examples of those results, the object of the present communication was stated to be, first, the familiar exposition of that theory ; and, secondly, to offer reasons why the chemical theory of volcanos originally proposed by Sir Humphry Davy, should not be discarded ** as a mere chemical dream," even on the high authority of Sir John Herschel. The foundation of the former theory being the observed augment- ation of temperature, as we descend from the surface of the earth » towards its interior, a brief statement of the general result of the observations hitherto made on that subject was first given, illustrated 534 Royal Inslitutioti. by reference to a table exhibiting the temperatures (on Fahrenheit's scale) corresponding to a variety of depths, from 50 feet to 200 miles below the surface of the earth, on the average (assumed for conve- nience, but corresponding closely v^rith that of observation,) of 1^ of increase of heat for every 50 feet of depth. The theory of the secular variation of the isothermal surfaces of the interior of the globe, considered as a cause of geological phsenomena, w^as then explained ; as it has been enunciated by Mr. Babbage in his paper on the temple of Serapis at Pozzuoli, read before the Geological So- ciety in 1834, and by Sir J. Herschel in letters addressed to Mr. Mur- chison and Mr. Lyell, communicated to that Society in 1837, and subsequently published by Mr. Babbage, together with his own paper, in his work entitled " The Ninth Bridge water Treatise :" the ex- treme generality of the terms in which Mr. Babbage's application of the theory to volcanic phaenomena, properly so called, had been announced, and the main object of his paper having been to explain by its means the pyrometric expansion of rocks as the cause of ele- vation, being assigned as reasons for his views having remained comparatively unregarded, until the more recent promulgation of views identical with them in their leading features, but more ex- plicitly developed in their application to those phsenomena, by Sir J. Herschel. The rise of the isothermal curves on the deposition of fresh solid matter on the earth's surface, their conformation to the sphericity of the earth in its central regions, but to the configura- tion of the surface as they approach it, and Sir J. Herschel's ap- plication of the theory to explain the elevation of continents, the production of the metamorphic rocks, and the origin of submarine volcanos and chains of volcanic vents, were severally noticed, and illustrated by reference to drawings. The attention of the auditory was directed, especially, to the generalization explaining the situa- tion of volcanic chains along lines of coast ; Sir H. Davy, it was re- marked, had assigned a reason why volcanos should only exist in the vicinity of great bodies of water, but it was reserved for Sir J. Her- schel to explain their actual disposition conformably to the coast lines, and also why they should exist at all. As the temperature attained by the bottom of the newly deposited mass of strata would be proportionate to the thickness of that mass, and would be the same as that existing at a depth within the earth equal to that thickness, (viewing the subject in the most general approximate manner, agreeably to the amount of our present know- ledge, and unavoidably disregarding a multitude of considerations which must enter into the discussion of the problem, in order to its exact solution,) the table of temperatures was now again referred to ; for the purpose of indicating, on the one hand, how great a thick- ness of deposited matter would be required for the original surface to rise to even a moderate temperature ; but, on the other, at how insig- nificant a depth (or thickness,) compared to the earth's radius, ade- quate temperatures would occur ; the latter consideration being illus- trated by a diagram exhibitingthe relative magnitudes of various depths corresponding to some of the tcmj)eratures in the table, as referred to a radius of twenty feet, representing that of the earth. Thus, at a Royal Institution, 5S5 depth equal to the height of Snowdon, 3571 feet, upon the average assumed, a temperature of 71" only would be found; at two miles* depth, only the temperature at which water boils at the earth's sur- face under ordinary pressure, or 212° ; and a depth of 30,600 feet, about 5^ miles, (considerably more than equal to the elevation of the highest peak of the Himalayas) must be attained, before we arrive at a temperature adequate to the fusion of lead, or 612° ; whereas the fusion of some of the most refractory earthy substances would be required for the production of volcanic phaenomena. At the depth of about 26 miles, however, which is less than T-J-irth of the earth's radius, a temperature sufficient for the fusion of cast iron would occur (which would of itself be sufficient also for that of many earthy and alkaline compounds) ; at little more than 33 miles deep would be attained the greatest heat of a ffint- glass furnace ; at 37 miles soft iron would melt * ; at 50 miles, a temperature of above 5000° Fahr. would be obtained, and at 100 miles, only ^'„th of the earth's radius, one of nearly 1 1 ,000°, either of which, from all ana- logy, would be more than adequate to the effects required. If the immense activity generated by such heats may be admitted to take place at these depths, there will be no difficulty in conceiving its extension upwards to depths less great, and finally to the surface of the earth. The second part of the subject was commenced by a statement of the chemical theory of volcanos, as originally announced by Sir Humphry Davy, in the Phil. Trans, for 1808, and afterwards re- peatedly advocated ; admitted by him, even when he finally rehn- quished it in favour of the theory of an ignited nucleus of the earth, to be adequate to the explanation of all the phsenomena ; and sub- sequently adopted and expounded in greater detail by Dr. Daubeny. The inference was then draw^n, that if the theory of volcanos depend- ent on that of the secular variation of the isothermal surfaces were true, (and on this point a strong affirmative opinion was expressed) then the chemical theory must also be true, as being necessarily in- volved in the former. This was argued principally on the following grounds : the new deposits formed at the bottom of the sea by de- trital matter must inevitably contain much carbonaceous and other combustible materials derived from organized beings, and these would become distributed, sometimes in a finely-divided state, intimately mingled with earthy bodies, — that is, with the oxides of the earthy, alkaline, and common metals. At the exalted temperatures implied in the theory, many of these oxides, including those of the earthy and alkaline bases, would become reduced to the metallic state ; the ignited water with which the whole would of necessity be saturated, would be decomposed ; its oxygen re-oxidizing the bases, and its hy- drogen being evolved in an uncombined state. Now one of the most abundant elements of all the detrital matter would necessa- * As the expressions of many of these high temperatures in degrees of Fahrenheit difTered from the estimates commonly stated, it may be well to add that they were obtained from the experimental resuhs of Wedg- wood, Prinsep, Prof. Daniel!, and others, all having been corrected agree- ably to the pyrometrical researches of the chemist last named. 5JI6 Notices respecting Nevi Books. lily be oxide of iron, which would thus be presented, in a state of minute division, to incandescent, but enormously compressed free hy- drogen, by which, agreeably to known results of experiment, it would be reduced to the metallic form, water being re- composed. A new affinity would now come into action : finely divided metallic iron being in intimate contact with the earthy and alkaline oxides, they would be reduced, as in the ordinary method of obtaining potas- sium and the process by which Davy and Berzelius first succeeded in de-oxidizing the combustible bases of silica and alumina, and would eventually re-act upon the water still present. By this constant cir- culation of affinities, exerted simultaneously in diflferent portions of the heated mass, according to their respective temperatures and to the local distribution within it of the various substances evolved, (dependent on their respective properties, as modified by the enor- mous pressures to which they would be subject,) chemical equili- brium would alternately be established and subverted ; and all the phsenomena and effects of plutonic and volcanic action would ensue — as originally suggested by Davy; — but as simple consequences of the secular variation of the isothermal surfaces, as explained by Bab- bage and Herschel ; the latter theory being a wider generalization, and including the former as one of its elements. Mr. Poulett Scrope's views of the origin and constitution of lava, &c. hitherto regarded as so anomalous, were also briefly alluded to as other probable truths involved in the new theory ; and the com- munication terminated with some general reflections, including the remark, that the names of Babbage and Herschel united would now descend to posterity associated with the history of geological dyna- mics, as they had already been with the improvement of many branch- es of mathematical analysis, and with the progress of some of the more recondite departments of physical science. May 18. — Mr. Faraday on the solid, liquid, and gaseous state of carbonic acid, illustrated by Thilorier's apparatus. LXXX. Notices respecting New Booh, Description d'une Collection de Min^raux, formee par M. Henri Heu- land, et appartenant a M. C. H, Turner, de Rooksnest, dans le ComU de Surrey en Angleterre. Par A. L4vy, Membre de VUniversite de France, etc. Trots volumes, avec un Atlas de 83 Planches, WE have quite accidentally omitted sooner to notice the above very valuable work on Mineralogy, for such we deem it to be, al- though described merely as a catalogue. Those who are engaged in the examination of minerals, and particularly of their crystalline forms, cannot fail to derive much useful assistance and instruction from this publication. It appears from a notice prefixed to the work, we presume by M. Heuland, that many years had been occupied in forming the collection, and under peculiarly favourable opportunities, for obtaining the finest and most rare specimens of every variety of mineral. The prefatory notice also states that the descriptions were drawn up several years since by M. L^vy, and might, if he had Notices respecting Neit) Books. 557 acted with good faith towards M. Heuland, have been long since published. It is however stated, that after receiving a large sum of money during the progress of the work, that M. L^vy " promettait bien de terminer les planches, mais il promettait toujours, et n'ache- vait rien." It is afterwards even stated that for the completion of the work M. Heuland lies under obligation to the friendship of Mr. J. H. Brooke and his son, and other gentlemen whom he names. The delay has, however, very little, if at all, impaired the useful- ness of the work to the mineralogist, in reference to their geogra- phical relations, and the great variety of their crystals. It is difficult to select, but we would direct the reader's attention particularly to the extensive series of forms of carbonate of lime, sul- phate of barytes, topaz, epidote, pyroxene, and idocrase ; and among the metals red silver, blue carbonate of copper, and other of the less common substances ; and indeed, we cannot but express our sur- prise that so large a collection, containing so great and such a splendid variety of crystals, should be found in any single cabinet ; and if it were not for the full, and, we conclude, accurate descriptions of the specimens given in the work, we should greatly regret that they were rendered less acceptable than the cultivator of mineralogy would desire, by the distance of Mr. Turner's residence from London. To give some idea of the extent of the collection, we may remark, that of carbonate of lime, the substance first mentioned, 513 varieties are described ; the crystalline forms of it occupy ten plates ; these require 158 figures, which are drawn and engraved with great clear- ness and precision : besides these, the crystalline forms of arragonite and magnesian limestone occupy two plates. The analyses and che- mical formulae of each substance are included in its description, and we do not think that we can give a better idea of the manner in which the work is conducted than by copying a portion of it which relates to red silver, of which 55 varieties and 106 specimens are described, with engravings of 39 crystals. The first 14 varieties, all we think it requisite to give, are thus de- scribed ; *' ARGENT ROUGE. ** Caracteres d^finis. Thenard. Formule chimique. " Analyse. Argent 58. 2 A « S^ + 3 A^f S«. Antimoine. . 23,5. Soufre , ... 16. Perte 2,5. 100,0. *' Forme primitive. Rhomboide obtus de 108° 30'. " Clivage. Parall^le aux faces du rhomboide primitif. " Pesanteur sp^cifique. 5,5886... 5,846. Cristaux de Beschert- gluck. " Caracteres indejinis. ** Chimiques, Au chalumeau, dccrepite en repandant une odeur 538 Notices res])ecting Nex^ S5 55 >5' =^' ^* ^* ^ i ^ i i ^ i i » ^ =*. s ^ ^ I ^ > E>) sT M H 5e ? a; >5 ■A ^ % 'A is J5 » «« -^ ococ^TJ•coc^^Oloc»coto^O(^l(^^vo■<*co<^l';fcoo^— < C0C0"^'^rrc0C0C0C0-«3'C0CO'^rl rrcocoCOCO-^COCO-^rtCOCOCOcocOCOCO-'t^'^'^rOCOCOCOCO o«^^QO^OTfln*lOOt^ COCOCOTyTyrf^COrOTf-»^-^ TtTtT}"COCOCOC'3-<:t'rtTtTfTtTt-rJp ip «p in »p ci coTf'^-'^cococococococo-^cooi cococi cococococo-^cocococo (N iO*cococococococo'^'>^coTrcocococo ;^c^'^•^co6■r^<(^r^^bl^co6cb^^'^<^6■rt<^>.^bcoco — cococo"^tr5i/5iO'^'^icuo"^-<*'^Ttn<'«*coco'^-^"^»o-^Tr'^TtrfTtTt co^^a^oa^ — com t^ip CO (^ c^ o^ (M a\ O o^o^o^c^o^0^o^o^o^o^o^0 c^o^c^lO^O^O^C^C^o^o^c^lO^O o^o^o^o^ coOOJOI-NCIOICNOIC^CNCNCOC^C^tNCICNClCNCNOCNOICICOCIC^CICN O r^.-_/ »jvw i^uo— 'C» fTi— ■'I'lOiO tCiOo^O^O^C^O^c^ C<0 O 0^0^0^0^0 O O O O 0^6^0^0^0^0^CT^C^O^O^C^O <^0>om3^ OC0CIC0r0ClCI0lo o LONDON AND EDINBURGH PHILOSOPHICAL MAGAZINE AND JOURNAL OF SCIENCE, SUPPLEMENT to VOL. XIL, THIRD SERIES. LXXXII. Researches on Heat, Second Series, By James D. Forbes, Esq., F.KSS. L. ^ E., Professor of Natural Phi- losojphy in the University of Edinburgh,^ § 1, On the Use of the Thermo- Multiplier, § 2. On the Polar- ization of Heat by Tourmaline, \ 3. On the Laws of the Polarization of Heat by Refraction, § 4. On the Laws of the Polarization of Heat by Reflection, § 5. On the Circu- lar Polarization of Heat, 'T^HE first series of these researches, in the exact form in which they are printed, were laid before the Royal So- ciety on the 19th January 1835 f. The whole of the experiments there described were made, and the paper written and printed, within a space of time little exceeding two months. This haste, unfavourable to composition, I considered as a less evil than postponing for a period of time, which must have been considerable, the publication of a class of facts which might be said almost to embrace a new science. The professional duties which pressed upon me during the whole continuance of those experiments, then called imperatively on my atten-' tion, and during the remainder of the Session my time was devoted to them. The summer I devoted to a foreign excur- sion, some of the results of which I afterwards digested ; and it was not till the commencement of the winter session which has just closedj that I prepared, with a fresh stock of health and spirits, to reinvestigate the whole subject of the Polari- zation of Heat, and to assign numerical values to the effects, whose existence I had before been contented to prove. § 1. On the Use of the Thermo- Multiplier, I have succeeded in rendering the application of the thermo-multiplier considerably easier, and more delicate than formerly. In my last paper, art. 5, I described the application of the telescope to determine accurately the amount of the deviation of the needle of the instrument in- dicating degrees of temperature. I have made the arrange- ment more permanent, placing the instrument on one shelf * Abridged by the Author from the Transactions of the Royal Society, vol. xiii., having been read before the Society May 2nd, 1836. f [Prof. Forbes's First Series of Researches on Heat appeared in Lond, and Edinb. Phil. Mag., vol. vi. p. 134 et seq.'] Phil. Mag, S. 3. Vol. 12. No. 78. Suppl, July 1838. 2 Y 54>6 Prof. Forbes*s Researches on Heat. Second Series, of a solid press, and clamping a little arm carrying the telescope, and centred at a point in the prolongation of a vertical line, passing through the centre of the card of the galvanometer, to a shelf above. The little arm bearing the telescope, therefore, traverses the divided part of the galvano- meter card, just as a micrometer does the limb of an astrono- mical circle. The result of this application of optical power is, that equally accurate conclusions may be drawn within small limits of deviation, as if the deviations were greater, and observed in the ordinary way. This is important on several accounts, 1 . The instrument is not liable to those derange- ments which follow from exposure to considerable heat, — de- rangements difficult to allow for, and which I have not suc- ceeded in obviating. 2. The value of the degrees is more nearly uniform, and less liable to abrupt change; so that (as will presently be seen) within the narrow limits under which I am accustomed to operate, the deviations are almost as the forces. 3. The motions of the needle being much more speedy and certain within small ranges (particularly in its return to zero) much time is saved, and the consecutive observations are more accurately comparative. 4. By the use of the tele- scope all parallax in reading is avoided, and if a diagonal eye- piece be employed, the posture is much less fatiguing than in any other method of observation. Besides using this optical contrivance, I have increased the delicacy of the instrument, by adding a conical reflector so as to concentrate nearly parallel rays upon the surface of the pile. This contrivance is not my own. I saw one in an in- strument made on the model of M. Nobili's, in the possession of M. Quetelet, at Brussels, in 1832, which was the first mul- tiplier I had seen. This reflector increases the sensibility of the pile to heat from a given source seven or eight times, or in a proportion not very different from the area of its aperture to that of the pile"*. The length of the conic frustum which I employ is If inches, and its aperture If inches. It is well known that the deviations of galvanometers are • Suppose that we wish to have a conical reflector A BCD, such that the whole of the parallel rays which fall upon it shall reach some part of the sur- face AB of the pile, which is all that we want, we have .^^---''' this simple construction. ,^---"''' Let the length of the trum- F ^''^^ pet-mouth A E be given. Make F B equal and pa- rallel to it. Join F A, and ^ prolong the line to D, then is DAE the greatest inclination that the sides of the cone can have to answer the purpose intended. Thermo-Multiplier. 547 not, generally speaking, proportional to the forces producing them, and that for the most part angular spaces at greater di- stances from zero correspond to increments of force greater than for equal spaces near zero. Thus to cause the needle to advance from 25° to 30° requires a force greater than to make it deviate from 0° to 5°. Also the force indicated by a deviation of 30° is more than six times the force indicated by a deviation of 5°. M. Melloni has pointed out an ingenious method of comparing the values of the different parts of the scale. This consists in employing two constant sources of heat to affect the opposite extremities of the pile, and after observing their separate effects, noting their joint effect, which will not generally be equal to the arithmetical difference of the others. Thus let one source of heat force the needle in a positive direction to 30° on the scale, and a second source of heat acting separately produce a negative deviation of 25°, the effect of both acting at once will not be a positive deviation of 5° merely, but probably will indicate some greater number, as 6° or 7°. Thus, a true scale of degrees equal in value to those near zero may be constructed. Another mode of estimating the indications of the instru- ment has been used by M. Melloni, and it is one particularly adapted to our researches. It likewise gives much more uni- form results than might have been anticipated. Instead of noting the ^wfl/ or stationary deviation due to any heating cause, it is sufficient if vi^e note the arc through which the needle \s Jirst impelled, and employ a table of reduction, in- dicating the relation subsisting between the dynamical effect or first arc of impulsion, and the statical effect or that of final deviation*. My experiments have given the following results, and the last column indicates the actual intensities corre- sponding to the statical deviation in second column. Dynamical effect, or first Statical effect, or arc passed over. Permanent deviation. Intensity. 1.0 ' 1.2 1.2 2.0 2.3 2.35 4.0 4.5 4.65 6.0 6.7 7.1 8.0 8.9 9.6 10.0 11. 1 12.05 12.0 13.2 14.4 14.0 15.3 16.9 16.0 174 19.35 18.0 19.45 21.75 20.0 21.5 24.3 £• See Scientific Memoirs, vol. i. p. 329. — Edit,] 2 Y 2 548 Prof. Forbes's Researches on Heat* Secoiid Series. The mode of observation by the first impulsive arc I have invariably adopted for obtaining numerical results, and chiefly for these reasons: 1. It saves time, and thus renders conse- cutive observations comparable. 2. It prevents a long ex- posure of the pile to heat, which alters the zero point and in- jures its action. 3. It almost annihilates the effect of con- duction where substances, capable of retaining heat, are placed between the source of heat and the pile. It is a remarkable circumstance, that when both the cor- rections obtained from these tables are applied, we obtain (as far as 20° at least) a measure of intensity increasing, almost uniformly, with the arc first run through. This is found to depend on the circumstance that the curve, expressive of forces, in terms of the stationary deviation, is convex towards the axis, or the forces increase more rapidly than the arcs ; whilst the curve, expressing the stationary in terms of the momentary deviations, is concave to the axis, or the Statical effect increases in a less ratio than the Dynamical effect. The convexity of the one curve, almost compensating the conca- vity of the other, the relation obtained between the first im- pulsive arc and the calorific force is nearly linear. This will be best illustrated by comparing the true ratios of the forces obtained from the above table, with the simple ratio of the first deviations ; and to put it in greater evidence we shall suppose a deviation of 20°, which is greater than we have ever employed in these experiments. First deviations compared. Ratio. Ratio of Intensities. 20Oand 1° .050 .049 20 — 2 .100 .097 20 — 4 .200 .191 20 — 8 .400 .395 20 — 12 .600 .593 20 — 16 .800 .796 Since, therefore, even in this case, we should never have an error amounting to a unit in the second decimal place, I have contented myself in this paper with the employment of the simple arithmetical ratio of the first arcs passed over. It appears, then, that these effects are developed on the whole in a simple and uniform manner; and though such an investigation as we have undertaken of the instrument, was necessary to give us confidence in the numerical accuracy of the results, iA\ facts of importance might be determined with- out it, and even quantitative laws ascertained by a judicious conduct of experiments. Many persons, even though not unaccustomed to physical reasoning, have strangely inaccu- rate conceptions of the limits of possible errors. Nor is there a more important part of the science of experiment than to Polarization hy Tourmaline. 549 perceive where 'physical proof becomes satisfactory, though yet far removed from mathematical certainty. To supply the latter is a humbler and more mechanical task, which may be undertaken at leisure, as in this paper we shall partly attempt to do. § 2. Polarization of Heat hy Tourmaline* On this subject I have little to add. It does not possess the same theoretical importance as in the case of polarization by other methods. Double refraction is better shown by the phaenomena of depolarization by mica, described in my last paper (art. 46 et seq.), and the phaenomena attendant on the absorption of one of the doubly refracted pencils, are so ca- pricious and ill understood, even in the case of light, that it might hold or not for heat without altering our views as to the probable identity of the cause of both those physical agents. With heat from incandescent platinum the effects are extremely well marked. Thus with tourmalines E and F (see First Series, 22) I obtained for the ratio of the quanti- ties of heat transmitted, with axes of crystals parallel, and axes crossed, 100 : 76; or 24 per cent, of the heat was polar- ized (Jan. 19, 1836). When one of these tourmalines was combined with a mica plate, marked G, polarizing by trans- mission (see below art. 20), the proportion was 100 : 62, or 32 per cent, polarized of heat from incandescent platinum. With dark heat incomparably greater difficulty was expe- rienced. Excessively little heat could be obtained through the combined mass of tourmaline and the glass to which it is cemented, and of that little it appeared that but a minute por- tion was polarized, or at least absorbed by the action of the former. At one time I seriously doubted whether any per- fectly dark heat came out of tourmaline polarized in one plane only. I have reason to believe that, in my first experiments, there was a source of error arising from the form of the plates, which was not adverted to formerly. I have, however, satis- fied myself that even dark heat is capable of being acted upon by tourmalines in the same manner as light. In my experi- ments the quantity apparently polarized did not exceed one- seventh or one-eighth of the small quantity transmitted. This was in combination with a polarizing mica plate (marked I). $ 3. On the Laws of the Polarization of Heat by Refraction or Transmission. In my last paper on this subject, I stated the fact of the polarization of all the kinds of heat which I tried by trans- mission through thin bundles of mica placed obliquely. I stated the difficulties which I experienced, and the quantita- 550 Prof. Forbes's Researches on Heat, Second Series. live errors to which the results were liable. I showed at the same time that these errors were of a kind calculated to viask the effects of polarization, but not to produce them. The nu- merical results which I gave (I. Series, art. 44), were intended chiefly to show that, even under all these disadvantages, the effects which I observed were of an extremely important and obvious character, such as no slight or capricious anomaly could possibly have produced. No one who candidly reads the paper, or is aware of the labour of so extensive an inves- tigation in so new a field, can suppose that 1 intended to give these results as to the quantities of heat, of different kinds, polarized by passing through mica bundles, as definitive nu- merical results. I certainly did suppose that the different kinds of heat were polarizable in different degrees under the same circumstances, a conclusion which I am now prepared to establish. The extent to which the former paper had swelled, likewise prevented me from inserting the description of a multitude of precautionary measures, taken to show that errors, of whose existence I was perfectly aware, had no influence in producing the effects which I stated ; nor am I now going to enter into details of manipulation, which the experimentalist must learn for himself, and which would be highly tedious to any other reader. I will content myself with referring to the proofs al- ready stated in this Journal*, in justification of my experiments. The polarizing effect takes place only at the surfaces of plates, — the absorptive effect depends upon their thickness. Hence, to polarize heat effectively, a minute subdivision of mica into thin laminae is essential. This I formerly effected by a pen-knife. I have since, however, discovered a method much more effectual. A piece of mica, thrown into a brisk red fire, is split up, by the expansion of the air between its films, into a multitude of pellicles, which reflect light with almost metallic brilliancy, and polarize it intensely by trans- mission. Such mica plates 1 have used, one pair being marked G and H ; the other I and K. By experiments with both these pairs of plates I have been led to the conclusion, that some kinds of heat are moke po- larizable AT A given incidence THAN OTHERS. Between heat from an Argand lamp, and that from platinum rendered incandescent by the flame of alcohol, there is little difference ; but heat, unaccompanied by light, is much less polarizable than luminous heat, and that apparently in proportion to the lowness of its temperature. I may take the opportunity of giving one or two examples of such experiments. ♦ Lond. and Edinb. Phil. Mag., for November 1835, and March 1836. Polarization by Refraction, 551 Mica Plates I and K. Argand Lamp, with Chimney and Re- Jlector : 16 Inches from Centre of Pile. Dynamical Effect. Mean. Ratio. Parallel 15.6 . Crossed 4.2 i 15.67 . . . 27 : 100 Parallel 15.75^ Crossed 4.4 i 15.85 . . . 28 . 100 Parallel 15.95-' Dark Heat from Brass, warmed by Alcohol: 16 Inches. Parallel 10.55. Crossed 4.05 \ 10.57 • . . 38 : 100 Parallel ..... 10-6 ^ Crossed 3.9 i 10.55 ... 37 : 100 Parallel 10.5 ^ These are given as examples of the usual mode of pro- ceeding with such experiments, the zero point being ascer- tained between each observation, and the dynamical effect reckoned from it. On the whole, I obtained for the propor- tion of heat polarized, or stopped in the transverse position of the plates, the following numbers : Source of heat. Rays out of 100, polarized. Plates I and K. Plates G and H. Argand lamp 72 to 74 82 Incandescent Platinum, 72 79 Brass heated to about 700°, .... 63 68 Heat from the same source transmitted \ ^^ ^r» through glass, ] '-^ "* Mercury in a crucible at 410°, ... 48 Boiling Water, 44 49 It thus appears that the Plates G and H are capable of polar- izing no less than 82 per cent, of some kinds of incident heat : these plates I began to use in the commencement of Decem- ber last. The unequally polarizable nature of different kinds of heat having been controverted, I took several methods of assuring myself that the observed effects were not due to inequalities in the dimensions of the sources of heat employed, or to their variable distances from the pile. A multitude of proofs might be given, but I will content myself with stating one or two of the most decisive. 1. Incandescent platinum and dark hot brass were successively placed at the same distance of twelve inches from the pile ; a thin plate of glass being placed be- tween the latter and the pile, and two thick plates of glass between the former and the pile. The quantities of heat reaching the pile were thus almost equalized, and the result was, that the heat from a dark source, after transmission through glassy became as polarizable as that from incandescent 552 Prof. Forbes's Researches on Heat, Second Series. platinum^ although before nine per cent, less of it was stopped. 2. If heat from boiling water or hot mercury be not really less polarizable than that from luminous bodies, it must appear to be so in consequence of the surface being larger, or closer to the pile, and therefore seen at the pile under a greater angle. To show that this effect, if it do exist, is at least in- significant in relation to the effect due to the variable nature of the heat, I placed the brass heated to 700° at 12 inches from the pile, and caused its rays to be sifted by a plate of glass. I found that 73 per cent, of this heat was polarized by the mica plates I and K. I then removed the glass plate, and withdrew the heated brass from the pile, until the impression on the pile was nearly the same as before. This was at a di- stance of 26 inches, instead of 12. The source of heat was therefore seen under a much smaller angle than before. But instead of the polarization being augmented by this circum- stance, the change in the quality of the heat by the removal of the interposed glass reduced it to 64^ per cent. — an effect which must have been owing to that cause, and to that alone. Another experiment similarly conducted with the mica plates G and H gave 73 per cent, of heat sifted by glass polarized at a distance of 12 inches, and only 68 per cent, of heat from brass at 700° in its simple state, at a distance of 27 inches. In all these experiments it is clear that the result is true, in- dependently of any reduction for the degrees of the galvano- meter, since in each set the deviation is made the same. The general fact that heat from sources of higher tempera- ture is more polarizable by refraction, agrees with the cor- responding case of light. Heat of low temperature is least refrangible, and Sir David Brewster has found that light of less refrangibility is less completely polarized by a bundle of plates placed at a given angle, than the more refrangible rays*. Mica is preeminently adapted for the purpose of polarizing by its considerable diathermancy^ and by the extreme thinness of its laminae. I have, however, succeeded in polarizing heat by transmission through a bundle of rock-salt plates with pa- rallel surlacest. Two bundles consisting of three plates, or six surfaces each, polarized about one-seventh of the heat which passed in the parallel position, the angle of inclination * The question of the unequal polarizability of heat from different sources is resumed and very fully discussed in the Third Series of these Researches^ an abstract of which will immediately follow the present paper. t For a supply of this valuable substance I have been greatly indebted both to Sir Philip Grey Egerton, Baronet, of Oulton Park, Cheshire, and to Dr. Traill. . Polarization by Reflection, 553 lo the incident heat being about 55° ; but when all the six plates were combined into one bundle, and the mica plate I used along with it, not far from a half of the transmitted heat was polarized*. The following is a very convenient mode of mounting the mica plates for polarizing. A cylindrical wooden tube is cut across at an obliquity of 34° to the axis. The plate of split mica is interposed and the parts reunited. The plane of po- larization or analysation may thus be made to shift through any angle by turning the tube containing the mica round its axis, and a small support is provided to preserve it in any position; whilst a graduation may easily be applied to the ex- terior of the tube, so as to mark the angular revolution. The convenience of this construction will afterwards appear. § 4. On the Laws of Polarization of Heat by Rejlection. The general fact of the polarization of heat by reflection was ascertained by me in December 1834-, and I stated the result in my former paper, art. 45. Under any circumstances the experiment is a troublesome one, but I have succeeded in arranging it in perhaps as satisfactory a way as it admits of being done. The great difficulty arises from the minuteness of the quantity of heat reflected, and consequently the large quantity absorbed by the plates, which complicates and ob- scures the effect. This is more particularly true with dark heat, which, at the same time, furnishes the most important case to be examined. The effect of the absorbed heat is to produce a powerful secondary radiation. My first inquiry on resuming the subject was to ascertain the relative order of several different substances as to their power of reflecting heat. This was not proposed to be done with a view to a general inquiry into that important subject, which I reserved to another occasion, but simply to ascertain what reflecting surfaces might be best employed in polarizing by reflection. Several series of experiments gave the follow- ing arrangement of substances according to their power of re- flecting heat, at an incidence of 45°, beginning with the most perfect reflector. Polished speculum metal. Mica, split by the hand into thin plales. Mica, split by heat (see p. 86). Thick plate of mica. * Such plates being equally permeable to every kind of heat, as M. Mel- loni's admirable experiment shows, would probably enable us to polarize cold, or to show the negative effects due to a reduction of temperature. This experiment I have not tried. 55i! Prof. Forbes*s Researches on Heat Second Series, Rock-salt, with a thin coating of varnish. C Polished rock-salt. ^ Glass. (^Alum. The three last substances (so different in their diathermancy) were nearly equal in their reflective power for dark heat (from brass about 700"). The above order did not, however, appear to be changed for heat from incandescent platinum, except that glass seemed to stand above alum and even salt. In a general way, we may consider the measure of metallic reflec- tion to be from two to three times as great as that from mica split by heat, which is also very superior to a single surface of mica. Glass, salt, and alum seem to reflect but a third or a fourth part, or even less, of that furnished by the laminated mica. I did not, as I have said, stop to prosecute these experi- ments; they clearly showed that of the substances which I tried, mica split into thin films afforded the most copious re- flection (next to the metals), and this was the very substance which from the first I had employed. They likewise satis- factorily showed the cause of the failure in former attempts to polarize by reflection, seeing that, for dark heat, glass is almost the worst reflector that could have been used, and as it likewise absorbs almost all the heat, transmitting very little, the effect of secondary radiation is increased. Hence the difficulty experienced by Professor Powell and others in getting any results at all* before the thermo-multiplier wa& devised, and the failure of the attempts of Signor Nobili of Florence even with its aidf . The last-named eminent philo- sopher failed also in obtaining traces of polarization by me- tallic reflection, which was not to be wondered at, as on an- other occasion we shall be able to make to appear. The form of apparatus which I have more recently em- ployed for experiments on polarization by reflection was sug- gested to me by the present astronomer royal, Mr. Airy, after the publication of my first paper. It is represented in section in the figure in the opposite page. AB and CD are two reflecting surfaces of mica fixed to blocks G and H ; the former of which is attached to a board TU, carrying the lamp or source of heat S, and revolving in a horizontal plane round T as a centre ; — the latter (H) is per- manently fixed relatively to the pile P, provided w^ith its conical reflector. The surfaces AB, CD are parallel, and make angles of about 5Q^ with the horizon ; consequently the heat falling * Edinburgh Journal of Science, N. S., vols. iii. and v. t Bibliotheque Universelle, Sept 1834. Polarization hy Rejlection. 555 on AB at an angle* of 34° with the surface, is reflected in the direction EF, which, by the construction, is a vertical line. From the surface CD, on which, at incidence, it also falls at an angle of 34°, it is reflected to the pile, whose opening in- clines downwards at an angle of 22°, so as to receive the rays directly. From this it is clear that the whole apparatus con- nected with the first plate AB may revolve round the vertical line EF as an axis, until the plane of section be perpendicular to the plane of the paper, and that yet the heat shall be cor- rectly reflected to the pile. In this case it is clear that the planes of reflection becoming perpendicular, a minimum of heat will be reflected if polarization take place*. Such appears to be the case with all the kinds of heat that J have tried. The disturbing influence of conduction is here more difficultly avoided, and serves to diminish the apparent effect. The quantities of heat reaching the pile from any non-luminous source are always small. The results, how- ever, are well marked, and seem decidedly to indicate that under the particular circumstances of the observation, dark heat is more completely polarized than the more reflexible * Square tubes of wood serve to inclose the apparatus and facilitate its adjustment. Other means not represented in the figure were also used for preventing direct heat from reaching the pile in any position. 556 Prof. Forbes's Researches on Heat. Second Series, heat from an Argand lamp, whilst that from incandescent platinum was more polarizable than either. The following results were obtained on the 12th March, 1836. The source of heat was in all cases at a distance of six and a half in- ches from the centre of the first reflecting plate, and the whole length of the dotted line PFES was about sixteen inches. The reflecting plates were composed of ten or twelve laminae of mica, split with a pen-knife, and the plane of re- flection was perpendicular to the principal section of the mica. Rays out of 100 polarized. Argand lamp without reflector, .... 55 Dark heat, from brass about 700°, ... 61 Incandescent platinum, 65 A mica-plate placed between the two reflecting surfaces in the figure, perpendicularly to the reflected ray, is capable of de- polarizing the heat, as in the case of heat polarized by trans- mission (17th December, 1835). The fact is simply men- tioned here, as we do not at present resume the subject of de- polarization. I made some experiments, with a view to the determination of the maximum polarizing angle for heat, with a more conve- nient apparatus than the one above described. It is well known that the following law holds for polar- ized light. When lights polarized in any plane^ is reflected from a refracting surface AT the polarizing angle for that surface^ it is "wholly polarized in the plane of incidence. If it be incident at a SMALLER angle than the polarizing anglcy the refected light is polarized in a plane lying on the farther side of the plane of incidence from the plane of primitive polarization. If it be incident at a GREATER angle than the polarizing angle, the plane of polarization will be on the same side of' the plane of incidence as at first. Now, this I have fully verified in the case of heat. Having polarized heat by transmission through a mica bundle, in a plane inclined + 45° to the plane of reflection, which it subsequently under- went at the first surface of a thick mica plate, I examined its state of polarization by another similar mica bundle interposed between the reflecting mica and the thermal pile. I' found that at great incidences the plane of polarization was on the same side of the plane of reflection as at first, whilst at smaller incidences it was thrown to the opposite side. I varied the incidence until the plane of polarization coincided with the plane of reflection, when I concluded that I had reached the polarizing angle. This was found by the quantity of effect when the plane of analysation was inclined -f- 45° and — 45° to the plane of reflection. With dark heat, from brass at Circular Polarization, 557- 700°, I estimated the polarizing angle to be 57° nearly (16th March 1836). By experiment I found that the polarizing angle for the same mica surface and for homogeneous red light was 59°. § 5. On the Circular Polarization of Heat. In my last paper I showed (art. 75) that heat may be circu- larly polarized, like light, by the doubly refracting action of a plate of proper thickness. This circumstance is indicated by an equal quantity of heat reaching the pile in all positions of the analysing plate. Last summer it occurred to me that it was probable that rock-salt, refracting heat almost as it does light, would cause it to undergo total reflection at a proper incidence. Sup- posing this to be the case (and I had afterwards reason to be- lieve that such had been shown to be the fact by M. Melloni), I then foresaw the possibility of trying an experiment of the most conclusive character, as to the nature of heat, — its sus- ceptibility of becoming circularly polarized by means of two total internal reflections, as in the admirable experiment of Fresnel in the case of light. Various circumstances prevented me from trying this expe- riment until the end of January last [1 836], when I procured a rock-salt rhomb, similar to that of glass used by Fresnel, but having its angles calculated by FresneFs formula, for the refractive index for light of rock-salt. I took the smaller of the two angles which the double solution of the quadratic equation gives, on account of the smaller dimensions required for the rhomb. This angle is nearly 45°. On the 1st of February I performed the experiment with complete success, though with an apparatus less perfect than I afterwards pro- cured. When the plane of reflection coincided with, or was per^ pendicular to, the plane of primitive polarization, the heat (whether wholly dark, or derived from incandescent platinum) came out unchanged, that is, on placing the analysing plate in azimuth 0° and 90° relatively to the polarizing plate, the ratio of the effects was the same as if no reflection had taken place. When the plane of first polarization was inclined -f-4:>° or — 45° to the plane of reflection, and the analysing plate was placed in the parallel and rectangular positions to the polar- izing plate, the ratio of the effects was totally changed, and was, in some instances, reduced nearly to unity. I'his took place whether the rhomb or the polarizing plate was move- able. 558 Prof. Forbes's Researches on Heat, Second Series. When the plates I and K were used, the ratio was raised by inclining the plane of reflection 45°, from 37 : 100 to 60 : 100; and when heat from incandescent platinum was em- ployed, from 28 : 100 to 64?: 100. It occurred to me, that, somewhat above the superior angle of total reflection indicated for light, the effect of apparent depolarization would be more perfect, and a ready way of doing this presented itself by the use of two prisms of rock- salt, having angles of 60°, with which I provided myself. The superior angle of total reflection for rock-salt (whose index of refraction is 1*56) is 57° 28' nearly, for light, and since it increases rapidly as the refrangibility diminishes, it was reasonable to expect it to be still higher, or not far from 60° for dark heat (of low refrangibility). The two prisms, ar- ranged as in the figure below (which is a ground- plan), fulfilled the required conditions, the dotted lines indicating the path of the rays of heat through the prisms ; and the result corre- sponded to my expectation. When the plates I and K were used to polarize and analyse, and the planes of total reflection and polarization were parallel, the ratio in the rectangular positions of the analysing plate was 40: 100; whilst, when the plane of first polarization was inclined 45°, the ratio was raised as high (in one series of experiments) as 94*5: 100. With the same apparatus, and with heat from incandescent platinum, the ratio was raised from 29 : 100 to 84 : 100. Thus the astonishing properties of rock-salt enable us most completely to extend the analogies of light even in their most complicated cases to the phaenomena of heat. We are naturally led from the consideration of circular polarization produced by two known methods in the case of light, viz. by transmission through a thin doubly refracting plate, and by total reflection in a refracting medium, to con- sider the third mode in which it has been effected, that is, by metallic reflection. In this case, also, the analogy holds as to the general fact, which I have succeeded in completely esta- blishing under several circumstances. Whilst the copious reflection of heat which takes place at metallic surfaces, ren- ders it easier to obtain distinct results than in some other Circular Polarization. 559 cases, the intricacy of the subject, and some deviations from the Jaws of light, as established in Sir David Brewster's re- markable paper on this subject*, demand a more prolonged investigation than I have yet been able to give to it. In the hope of being able to resume it in another paper, I content myself at present with a reference to the facts respecting Me- tallic Reflection, communicated to the Royal Society of Edin- burgh on the 21st of March 1836, and printed in their Pro- ceedingsf. * Philosophical Transactions, 1830. t The following is the Memorandum on the subject, extracted from the Proceedings of the above date. " I have recently ascertained the following facts respecting heat. " 1st, That heat polarized in any plane, and then reflected from the sur- face of a refracting medium, changes its plane of polarization in a manner similar to what obtains in the case of light. Thus,, with a thick plate of mica, which polarized homogeneous red light most completely at an inci- dence of about 59°, the plane of polarization of reflected polarized heat remained on the same side of the plane of reflection when the incidence was greatf and was on the contrary side when the incidence was small. The limiting angle of incidence was about 57°, which therefore should be the polarizing angle of dark heat for mica. This mode of observing the po- larizing angle offers some advantages above more direct methods. " 2ndly, Metals polarize heat extremely feebly by reflection. I have carried my experiments up to 85° from silver, yet even there but a small share is polarized. The effect is, however, distinctly recognisable through a considerable range of incidences. The effects are such as would indicate the maximum polarizing angle to be even much higher ; perhaps it never attains a maximum. This fact corresponds to that in the case of light, ex- cept that the maximum polarizing angle is 73° (Brewster). Did metals act on light like other bodies, we should conclude, from the polarizing angle being greater, that heat is more refrangible than light. An important re- mark of Sir D. Brewster's, however, shows the statement I have made to be in conformity with the views of the nature of heat which I have pub- lished. He finds the maximum polarizing angle to be greatest for the least refrangible rays. " 3rdly, Heatpolarized in a plane inclined 45° to the plane of subsequent reflection at silver, has its nature changed as in the case of light, and pre- sents the conditions of elliptic polarization, though the ellipse is much more elongated, even at great angles of incidence. " 4thly, T?i;o reflections from silver increase the polarizing effect of metals. This fact has its counterpart in light. Two reflections likewise produce an increased tendency to circular polarization when the plane of reflection is inclined 45° to that of primitive polarization. This effect increases with the obliquity of incidence up to considerable angles. " These observations have been verified in the case of heat from various sources, obscure as well as luminous." [ 560 ] LXXXIII. On the Composition of certain Mineral Substances of Organic Origin, By James F. W. Johnston, y^.M., F.R,SS. Lond. and Ed., F.G.S., Professor of Chemistry and Mineralogy, Durham* IV. Retin Asphalt. T^HE substance described under this name by Mr. Hatchett -*- is well known to mineral collectors as occurring in the wood coal deposit of Boveyf. It is met with in lumps of various sizes, generally of an earthy aspect and fracture, rarely compact and glistening, and of a colour more or less brown. Throughout its substance are frequently observed small por- tions of carbonaceous matter, long, small, apparently pointed, and when broken across exhibiting under the microscope a hollow quadrangular cavity as if they were the remains of slender spines, or of leaves allied to those of the Coniferae. In the air it melts when heated, burns with a bright white light, much smoke, a slightly aromatic odour, and leaves a pure white ash consisting of alumina with a little silica. Alcohol dissolves a large portion of it, giving a dark brown solution, and leaving a light brown residue. This residue still contains a large quantity of organic matter, which appears, however, to possess in common with asphaltum, which Mr. Hatchett supposed it to contain, no other property but that of being insoluble in alcohol. A portion of the retin asphalt carefully burned left 13*23 per cent, of residuum, after ex- haustion by boiling alcohol 32*52 per cent. It consisted, therefore, of Resin soluble in alcohol 59*32') Insoluble organic matter 27*4^5 > 100. White ash 13*23 ) This proportion of the constituents is probably variable. The insoluble matter heated in a tube, blackens and gives off' empyreumatic products. At a red heat in the open air it burns. Resin of Retin Asphalt. Retinic Acid. Evaporated and the residue dried at 212°, the dark brown alcoholic solution leaves a light brown resin largely soluble in ajther, (from which alcohol throws down the greater part,) and less so in alcohol, from which it is wholly precipitated by water. At 212° it emits a peculiar resinous odour, which be- comes more perceptible as the temperature is raised. At 250° Fahr. it begins to melt, and at the same time to lose in * Communicated by the Author. [t Mr. Hatchett's account of this substance will be found in Phil. Mag., First Series, vol. xxi. p. 147.— Edit.] Prof. Johnston on Minerals of Organic Origin. 561 weight ; at 320° Fahr. it is perfectly fluid, and at 400° it gives off' minute bubbles as if slowly effervescing. 6-885 grs. dried at 212"^ raised to 25o" had lost 0*06, to 320° —0-09, and to 400° ~0-24< gr. Dried at 212° and burned with oxide of copper 6*492 grs. gave water 5*11, carbonic acid = 18*045. Heated to perfect fusion 7*i29 grs. gave water = 5*58, car- bonic acid = 20*41 grs. These results are equivalent to Dried at 212°. At SOO^. Carbon = 76*860 77*414 Hydrogen ... = 8*749 8*508 Oxygen = 14*395 14*078 100* 100- Calculated according to the formula C^ H5 O, we have 7 Carbon ... = 535*059 = 76*716 per cent. 5 Hydrogen^ = 62*398 = 8*946 1 Oxygen... = 100000 = 14*338 697*457 100* This formula is beautifully simple, but the hydrogen found by experiment is obviously too little to warrant us in adopting it. The true constitution, therefore, I believe to be Cgj Hj, O3 , giving 21 Carbon ... = 1605*177 = 77*171 percent. 14 Hydrogen = 174*7144 = 8*400 3 Oxygen... = 300*000 = 14*429 2079-8914 100* which allows for the presence of a little moisture in the oxide of copper. This constitution is corroborated by two experiments, in which the combustion was imperfect, but which gave the car- bon and hydrogen respectively, in the proportions of Atoms 3 Carbon to 2*066 Hydrogen. 3 2*143 As the nature of the retinic acid and the circumstances under which it occurs lead us to refer its origin to some tree belonging to the family of pines, we should expect to find some relation between its constitution and that of the colo- phonies, or pine resins of recent production. According to Heinrich Rose, crystallized gum Elemi consists of Coq Hj^j O, and crystallized Colophony of 4 (Cjo Hg) -f 40, Phil. Mag,, 5. 3., Vol. 12, No. 78. SuppL July 1838. 2 Z 562 Prof. Johnston on ike Composition of certain Mineral in which we observe an interesting approximation to the number of atoms of carbon in the retinic acid. In fact if gum elemi were so changed that an atom of carbonic acid should replace two of hydrogen, or colophony so that one of carbonic oxide should replace two of hydrogen, retinic acid would be formed, since c«, H., o, + CO, or c» H.6 o. , + co C,iHi4 03or7(C3H,) + 30 That the resinous matter formed upon or exuding from the trees deposited in the Bovey coal field was ever identical in constitution with recent pine resins, or that if so it has during its long burial undergone a change so simple as that indicated by the formula, it is impossible for us to determine ; neverthe- less researches of this kind are, I think, likely to throw an additional light on the nature and products of the vegetation of remote epochs, correcting or confirming the deductions of the fossil botanist, and it may be suggesting to him new in- quiries. Salts of Retinic Acid, Retinate of Silver, — Alcoholic solutions of nitrate of silver and of retinic acid give a slight precipitate when mixed, which is determined however more fully by the addition of a small quantity of ammonia. It is of a brown colour, but speedily blackens by the action of the light. It is soluble to a considerable extent in alcohol, giving a dark brown solution. It is washed therefore with difficulty, and is in great part car- ried through the filter before the purity of the remainder can be depended upon. The filtered solution on standing gradually deposits a black precipitate containing more silver, due in all probability to a decomposition of the acid and re- duction of the silver, or to the presence of some foreign re- ducing substance. The small quantity which falls on the ad- mixture of the two alcoholic solutions, previous to the addi- tion of ammonia, contains also an excess of silver, which may be due to a similar cause. Heated to 300° Fahr., this and all the other retinates give out the peculiar resinous odour of the acid, and at a higher temperature the metallic salts melt, give off combustible pro- ducts, and leave a bulky charcoal. Three different portions, prepared by different processes and more or less perfectly washed, left on burning metallic silver equivalent to 4.1-780, 42-822, 4.3*585 per cent. Substances of Organic Origin, No. IV. Retin Asphalt. 563 of oxide of silver respectively. According to theory we should have C21H14O3 = 2079-8914 = 58-895 AgO = 1451-607 = 41-1()5 I 3531-4.984 lOO'OOO This exhibits a considerable difference from the experi- mental result. The third portion analysed was precipitated by a sohition of the acid in a?ther; it is quite possible, there- fore, that the error may be owing to the presence of reduced silver. At ail events the approximation is sufficiently close to show that the equivalent of the acid is represented by the same multiple of the elements as we have above deduced from direct analysis. Retinate of Lead. — An alcoholic solution of acetate of lead gives with one of retinic acid a dark brown precipitate, which on drying is of a light umber colour. Heated in the air it behaves like the silver salt, and when burned leaves oxide of lead mixed with a greater or less portion of metallic lead. It is nearly insoluble in alcohol, and therefore may be fully washed; but partly owing to the impossibility of burning it without loss of lead by volatilization, or to some other cause which has escaped me, I have not been able with specimens of this salt prepared by different methods, to obtain nearer approximations to the theoretical per centage than those fur- nished by the analysis of the silver salt. It is unnecessary, therefore, to insert the numerical results. Retinate of Lime is precipitated very sparingly and of a brown colour, when ammonia is added to the mixed alcoholic solutions of retinic acid and chloride of calcium. It is sparingly soluble in water, giving a pale yellow solution : when heated in the air it blackens, but does not melt, and at a red heat leaves carbonate of lime. Dried at 300° Fahr. 0*524 grs. left 0096 carbonate = 18*32 per cent., or 10*312 of lime. This would indicate a sesqui-salt, composed of Per cent. calculated . By experiment. li(C2iHi4 03) = 3119*837 = 89*758 = 89*788 1 CaO = 356*019 = 10*242 = 10-312 3475*856 100- On a single result however, and obtained from so small a quantity, no great reliance ought to be placed. The retinates of baryta and strontia may be obtained by digesting the caustic earths in alcoholic or aethereal solutions of the acid. It is difficult, however, by this method fully to 2 Z 2 564} Geological Society, saturate the base, a coating of the resinous salt being apt to exclude a portion of it from the action of the acid. The alkaline salts may also be formed by digesting the resin in a concentrated solution of the caustic alkali in which the salt formed is but sparingly soluble. With the results of this examination of the saks of the re- tinic acid I am by no means satisfied, though they appear to leave little doubt that the true equivalent is C.^, Hj4 O3. The difficulty I have found in obtaining them of a constant com- position, seems to demand so much more time for perfecting the investigation than the interest of the subject promises to compensate for, that I have been induced to leave it for a more inviting object of research. Durham, April, 1838. LXXXIV. Proceedings of Learned Societies, GEOLOGICAL SOCIETY. [Continued from p. 291.*] December 13, 1837.— A paper " On the Geology of the South- east of Devonshire ;" by Robert Alfred Cloyne Austen, Esq., F.G.S., vjras read. The district described in this memoir, is included within the rivers Exe and Dart, and extends from the coast to the granitic region of Dartmoor. The formations of which it consists, are first noticed, then the faults, and, lastly, the probable amount of effects produced at each period of disturbance. 1. Formations. — These are considered under two heads : — 1st. ac- cumulations produced by actual causes ; 2ndly, those produced by causes in operation before the most recent disturbances, including tertiary, secondary, transition, and igneous deposits. The first of these subdivisions contains a description of the shingle, sand-hills, estuary deposits, and peat-bogs ; but the south-east of Devonshire presents no phenomena connected with them, deserving of particular notice. Tertiary Deposits. — ^To this class Mr. Austen assigns the {a.) raised marine deposits in estuaries, and {b.) raised beaches ; (c.) the accumulations of water- worn rocks in valleys ; {d.) the Bovey de- posit; (e.) ossiferous caves ; and (/.) the bed of angular chalk flints, and chert on Haldon and Blackdown. (a.) Raised Marine Estuary Deposits are considered to exist in the valleys of the Exe and the Otter, because those rivers, in their • We now resume our notice of papers read before the Society, which has been interrupted by the Anniversary Proceedings, as detailed p. 433 et seq. Geological Society. 5Q5 present state, could not have accumulated the sediment which forms the surface of the valleys, or have worn the vertical cliffs by which they are partly bounded. In the valley of the Exe, above Topsham, is a bed abounding with marine shells of existing species, but high above the reach of any tide. {b.) The raised beaches of Hope's Nose and the Thatcher were described by the author on a former occasion*; but in this paper he shows, that similar deposits occur to the west of Bovey-head, and at intervals along the whole southern coast of Devonshire. The upper limit of these beaches seldom exceeds 60 or 70 feet above the present sea-level. The raised beach to the west of Bovey-head, consists of shingle and indurated sand, associated, in the upper part, with red haematite, and it is overlaid by a thick mass of the same ere. This haematite is connected with the Upton iron lode. (c.) Accumulations of water-worn rocks. — In every valley, with the exception of that of the estuary of the Teign, are thick heaps of debris, derived principally from the adjacent formations, and occa- sionally containing bones of the elephant and rhinoceros. Simi- lar detritus caps all the ridges which lead up to the Haldons ; also the summit of those hills, Blackdown, &c. ; but the fragments are less water- worn on the tops of the ridges than in the valleys. (d.) The Bovey deposit is not described in this paper, the author intending to prepare a separate account of it. (e.) Ossiferous caves. — No [information is given respecting the contents of the bone- caverns, Mr. Austen referring to the accounts already published respecting those at Chudleigh and Kent's Hole. (/.) The bed of angular flints, containing in its lower part large tabular and angular blocks of chert and sandstone, and resting on the green sand of Haldon and Blackdown, is referred by the author to the tertiary series ; and the angular form of the fragments strongly distinguishes the bed from the overlying superficial debris. The blocks of breccia, composed of angular flints, cemented by a very hard sandstone, and scattered over the surface of the hills and along the valleys, particularly near Sidmouth, are likewise considered as the remains of a tertiary deposit, probably of the same age as the grey wethers of Wiltshire. In the blocks near Sidmouth, Mr. Austen has observed remains of shells, which he is of opinion belong to the freshwater genus Planorbis, and in the Haldon beds numerous individuals of the genus Cyprcea. Secondary Formations. — These consist of, (a.) chalk; {b.) green sand ; (c.) new red sandstone ; and {d.) coal measures. (a.) Chalk. — The prevailing divisions of this formation in the S.E. of England are stated to extend to Maynorst Cliflf ; but detached masses of lower chalk are found among the debris as far west as Peak Hill ; and a white calcareous bed rests on the green sand of Style Hill. {b.) Green sand. — This formation the author has traced along the * Proceedings, vol. ii. p. 102, [and Lond. and Edinb. Phil. Mag., vol. vi. p. 63.] 566 Geological Society. slopes of the hills flanking the valley of Bovey, where it had not been noticed by previous observers. The beds dip towards and form the lining of the Bovey basin. They rest on new red sand- stone, coal measures, limestone, slate, and perhaps granite, and, to a certain extent, are composed of the debris of these formations. A list of the fossils is given, and Mr. Austen states, that moUusca are almost wanting on Little Haldon, and he therefore infers, that the Haldon beds are of a more littoral nature than those of Blackdown. The conchifera also occur^ in single valves, and broken, and appear to have been drifted as well as water- worn. (c.) New Red Sandstone. — ^ITie subdivisions of this formation are stated to present the following geographical distribution, proceeding from east to west: 1. marls, with gypsum, as far as Sidmouth ; 2. sandstone, from that town to a little beyond Dawlish ; 3. shingle and conglomerate, to the western boundary of the formation, the pebbles being derived from the adjacent older rocks, and increasing in size towards the edge of the deposit. In some places, however, the shingle is associated with finely- grained fissile sandstone. From this distri- bution, the author infers, that the conglomerate marks the original shore of the sea in which the new red system was deposited; the sandstone, the finer detritus carried to a certain distance from it ; and the marl, the mud diffused through the water, and conveyed to a still greater distance*. The jointed structure is not very distinct, but it may be traced even in the conglomerates ; and from the best exhibited cases, the author concludes that the strata are divided into octohedral masses. Vegetable remains are found near Sidmouth. (d.) Culmiferous or Carboniferous Series. — After alluding to the rectification, in 1836, by Prof. Sedgwick and Mr. Murchison, of the error in the geological position of this seriesf, Mr. Austen states that it occupies, in South Devon, the whole of the valley between Great Haldon and the extremity of Dartmoor. He subdivides the series as follows : — 1st. Shales, which near the granite or trap, sometimes resemble the older slates. 2nd. Sandstones with beds of thick flagstone, as above Greyleigh and Biddlecomb, and below Lewell House. 3rd. Conglomerates, as at Ugbrook, the Orchard Well valley, and above Ryder Farm. The limestone of Chudleigh is stated to rise through the culmi- ferous strata N. of Ugbrook-park, and to the S.W. of the Bovey de- posit, to form a continuous band. The mineral contents of the series are various. Tin and copper occur beneath Ashburton Down and near Christow ; lead has been found in the same parishes ; and iron ore is contained in large quan- tities in the shale. t Where the rock approaches the granite, it is • [On this subject compare Mr. Brayley's paper on the consolidation of the new red-sandstone forraation, Phil. Mag. and Annals, N. S. vol. vi, p. 71 : see also Lond. and Edinb. Phil. Mag. vol. vii. p. 515, note. — Edit.] t [See Lond. and Edinb. Phil. Mag. vol. x. p. 388, and pres. vol. p. 510.] + [See Mr. Kingston's paper, Phil. Mag. and Annals, vol. iii. p. 359.] Geological Society. 567 much altered, and encloses numerous small garnets. Remains of plants are scarce, but impressions of Calamites have been found ; and minute portions of vegetable matter occur in some of the beds of sandstone. Transition System. — The culm measures rest unconformably on a series of deposits belonging to this system, and divided by the author into the following formations, in descending order : — 1. Rag Limestone. — A calcareous rock, coarsely laminated, of a dirty red colour, and abounding with stems of encrinites. Locality, Forest of Denbury. 2. Shale. 3. Great Limestone. — ITiis is the limestone of Newton Bushel and Torquay. It is distinctly jointed, the prevailing strike of the joints being, for one set, N.N.W. to S.S.E., for the other, W.S.W. to E.N.E.; but considerable variations are stated to occur in dif- ferent quarries. Organic remains are very numerous, both corals and shells. At its base the deposit presents several alternations of shale and black limestone, and contains some peculiar fossil shells. It passes gra- dually into the next formation. 4. Argillaceous Slates and Sandstones, generally Red. — This de- posit is of great thickness, forming the principal part of the slate- hills, and is sometimes worked for roofing- slate. It contains bands of limestone of a peculiar character. Organic remains occur only in the upper part, and agree apparently with those of the " great limestone." 5 . Lowest Bmd of Limestone. — The limestone between Staper-hill and Bickington, and on the highway road by Goodstone to Ashburton and Buckfastleigh, is assigned to this portion ; also that of Chudleigh, and the limestone at the base of Great Haldon is perhaps of the same age. The organic remains consist of corals and shells. Thin seams of carbonaceous matter also occur. Igneous Rocks. — These formations consist of granite, porphyry, and trap. The granite of Dartmoor was shown in 1836, by Prof. Sedgwick and Mr. Murchison, to be more recent than the carbonife- rous strata ; and Mr. Austen adopts the same view, as veins of gra- nite penetrate the culm beds at Higher Alway and Lower Alway, neaj* Bovey. The principal mass of Devonshire granite has in some places a height of 1800 feet, but over the whole of its area there is not the sHghtest appearance of any stratified deposit. The granite of Dartmoor is considered by Mr. Austen to be of different ages, as veins of coarsely grained are intruded among the common variety. Blocks of hornblendic granite are said also to occur, imbedded in the true granite ; and in some places the granite is so felspathic as to resemble trachyte. Trap Rocks — The author describes, with some detail, the horn- blendic trap dyke of Wear, and shows that it must have been irrupted subsequently to the deposition of the chalk, because fissures in the limestone, traversed by the dyke, are filled with fragments of various formations, including chalk, and are charged with manganese, an 568 Geological Society, eiFect produced by the intrusion of homblendic trap throughout this part of Devonshire. In the parish of Kington, veins of trap, on approaching the granite, are said to become more compact, and in the proximity of it, to be distinctly crystalline. Associated with the culm strata are bedded traps, apparently of contemporaneous origin ; but the close of the cul- miferous period is stated to have been marked by irruptions of the porphyry found at Pocombe-hill, and other places near Exeter. At Western,, in the parish of Ide, it rests upon the culmiferous shale ; but Mr. Austen says, it might be considered to rest on the new red sandstone, as that formation flanks the base of the hill. In the quarry, however, where the porphyry is worked, it has been cut through, and found to rest upon shale*. This rock has contributed largely to the formation of the conglomerates of the new red sandstone. Trap dykes are very common among the older slates, and have pro- duced decided effects on them, and the general features of the country. Their age the author does not attempt to define ; but from their being more abundant in the older than in the newer rocks, he conceives that they may have been, in part, irrupted before the latter were deposited. In the coast section, beds of hornblendic trap are included in the transition shale, to which they adhere by the lower surface, but not by the upper. Similar, imbedded, trappean rocks occur at Black Head, west of Babbacomb ; the sixth mile-stone between Teignmouth and Torquay; near the village of North Whilborough, and at East Ogwell. The author then describes the phsenomena, which appear to have accompanied the disturbance of the strata at different periods, be- ginning with those considered to be most recent. The undulations and deep combs in the new red sandstone, he aays, are not due solely to denudations, but to elevations and depres- sions of the beds while the formation was beneath the sea. On the surface there are no indications of disturbance, the angular irre- gularities having been rounded before the district became dry land. The Watcomb Fault, however, he conceives, was produced by a subsequent operation, as it preserves its angular outline ; and other instances are mentioned of unobliterated faults. Mr. Austen next describes, with reference to this part of the sub- ject, the raised, marine beds in the estuary of the Exe, the raised beaches at Hope's Nose, the Thatcher, and to the west of Berry Head ; he mentions also those which occur at intervals along the southern coast of Devon. • [I observed, in 1825, in one of the Radden quarries at Thorverton near Exeter, that the porphyritic amygdaloid was overlaid by the red marl, the sandstone of that formation appearing to graduate into the subjacent amygdaloid, which was also intersected by irregular nearly horizontal veins of the former rock. The phaenomena here are altogether such as might naturally be supposed to result from the intrusion of the igneous rock into the new-red-sandstone formation, at least j)rior to the consolidation of the latter, if not during its deposition. See the papers referred to in p. 566 note».-E.W.B.] Geological Society. 569 Another system of disturbances, the author assigns to the tertiary era, because it appears to have been in operation, during the time, when the Haldon and Blackdown tertiary beds were formed. The Haldon strata exhibit the following proofs of disturbance : — 1 . A partial destruction of the chalk, followed by the formation of a breccia of angular flints and sand. 2. The breaking up of this breccia and the production of a stratum, consisting of chalk flints, the breccia, quartz, granite and other rocks, all rounded. Mr. Austen then oiFers some observations on the probable changes in the extent of dry land during the deposition of the secondary sy- stems, indications of which, he conceives, are traceable in the charac- ters, and the thinning out of the formations between the chalk and the new red series. In alluding to the faults which aiFect the new red sandstone, he says, that the greater part of them may belong to the tertiary epoch. In the older formations, the evidences of disturbance during periods anterior to the new red sandstone, are referred chiefly to the unconformable position of the culmiferous strata with relation to the transition ; and consequently the disturbances, which gave the slates their present position, must have taken place anterior to the deposition of the culmiferous strata. With respect to the connexion between the age and the direction of the faults, the author says the district is too limited for any ob- servations to be of much value. The older disturbances, however, appear to have a north and south direction. The most remarkable cast and west fault is that of the valley of theTeign; and if the Wey- mouth Fault be prolonged westward, it would strike the coast of De- vonshire at the mouth of that river. Examples of depression as well as of elevation are mentioned in the paper, and it is said that the former are parallel to the latter, ranging S.S.W. and N.N.E. Jan. 3, 1838. — A paper was read on the " Geological Relations of North Devon," by Thomas Weaver, Esq., F.G.S., F.R.S., &c. ITie observations, which gave rise to this paper, were made during the autumn of 1837, in consequence of the discussions which had taken place relative to the position of the coal strata of the North of Devonshire*. The author states that he derived great assistance, during his investigations, from the Rev. David Williams, who kindly oflfered to be his guide. The survey, however, convinced Mr. Weaver, that Prof. Sedgwick and Mr. Murchison were perfectly cor- rect in placing the coal with the associated strata at the top of the series, and in removing it from the transition systems to which other observers had assigned it. The district, more particularly examined by the author, lies between the parallel of Bideford and Chilhampton on the south, and that of the Foreland (E. of Linton) on the north, and is bounded on the east by the meridian of High Down (four miles west of South Mol- tgn), and on the west by the Bristol Channel. * [Sec p. 566, note *.] 570 Geological Society, Before he proceeds to detail his own observations, Mr. Weaver gives a comparative table of the subdivisions of the strata, exhibited by Prof. Sedgwick and Mr. Murchison at the meeting of the British Association at Bristol, in August 1836 ; and those employed by the Rev. David Williams, in a section shown at the meeting of the same body at Liverpool, in September 1837. These subdivisions, he states, are essentially the same, though Mr. Williams considers the coal strata as belonging to the transition systems. The subdivisions, first established at the Bristol meeting, are adopted by Mr. Weaver, but he employs a nomenclature derived, for the greater part, from the localities where the strata are well exhi- bited. The following list contains the subdivisions in ascending order. 1. Foreland sandstone. 2. Linton calcareous slates. 3. Tren- tishoe quartzy slates and sandstone, including the Combe Martina limestone. 4. Morte slates. 5. WoUacomb sandstones, flagstones, and slates. 6. Trilobite slates. 7. Wavellite schistus and lime- stone. 8. Culmiferous shales (coal strata). The mineral composition, lithological structure, local variations, and relative order of superposition of each formation are fully detailed ; and the following inferences are given, as deducible from the whole of the evidence, collected during the survey. 'Iliat there is a general sequence of emergence from south to north, or from the culmiferous shales (8) to the Foreland sandstones (1), the dip being generally to the south. That from the Foreland sandstones (1) on the north to the Trilobite slates (6) on the south inclusive, the angle of dip increases from 20° to 80°, being 20° to 30° in the Foreland sandstones (1) and Linton calcareous slates (2), 45° to 70° in the Trentishoe quartzy slates and sandstone (3), 70° to 80° in the Morte slates (4) and WoUacomb sandstones (5), and generally in the Trilobite slates (6), though in the last a lower angle is sometimes observable on approach- ing an undulation. The general strike of the beds is from 10° to 15° N. of W. and S. of E. from a true meridian. ITiat on the other hand the Wavellite schistus, limestone, and shale (7) and culmiferous beds (8) undulate on a very large scale, and are occasionally subject to contortions upon a smaller. From the Foreland sandstones (1) to the Trilobite slates (6) in- clusive, the series is connected throughout, passing from one to the other in such a manner as to form a consistent whole, the parts of which cannot be separated one from another without arbitrary divi- sions. lliough the beds, from 1 to 6 inclusive, form one consistent, consecutive series, yet the subordinate parts are subject to change in different portions of the field, both mineralogically and in extent, and occasionally thin out, as in the case of the beds of limestone. On the other hand, the Wavellite schistus and limestone (7) and culmiferous shales (8), though apparently in some places in a parallel (conformable) position with the Trilobite slates (6), do, when thoroughly examined upon the line of outcrop in the district, form a break with number 6, and are unconformable thereto. Geological Society, 571 That this unconformity denotes two different oeras of deposition, an inference supported by the difference in the organic remains ; and Mr. Weaver further states, that he does not consider the occurrence of a few coal plants in the WoUacomb sandstones (5) as at all inter- fering with this inference. That the preceding data justify the conclusion, that the strata from 1 to 6 belong to a system distinct from that which includes the beds 7 and 8, the former constituting a peculiar transition group ; and the latter belonging to the true coal measures of England, the old red sandstone being alone wanting. In conclusion the author dwells upon the importance of attending to mineral composition in surveying extensive systems of rocks ; but he adds, that " the only safe guide in researcheb into the crust of the earth, is to keep constantly united in view, relative position, organic remains, and mineralogical characters ; and not to restrict our at- tention to one of these distinctions when judging of geological form- ations." January 17, — A paper by Dr. Bell, entitled "Geological Notes to accompany Major Todd's Sketch of part of Mazunderan," was first read. These notes were made during a journey from Teheran (lat. 35" 40' N., long. 50° 52' E.), eastward to Feeroozkooh, then northward across the Elboorz mountains, and afterwards along the course of the river Talar to the Caspian, and back to Teheran by the banks of the river Heraz. The authors observations are given in the order in which they were made during his journey, but the geological details may be classed as follows : — 1. Alluvium. — Teheran stands on a plain, consisting chiefly of the debris of limestone and trap rocks. In the bed of a river at the Caravanserai of Dalee Chaee, about 62 miles direct E. from Te- heran, is a loose conglomerate composed of fragments of limestone and trap, imbedded in dried mud. A similar deposit forms low hills and valleys in several other places along the line of route, followed by the author, as at the river Gazan Chaee, and on the summits of the hills bordering the plain of Feeroozkooh. Below Pul-i-Seffeed, on the Talar, is a conglomerate, formed of debris from the neighbour- ing mountains, united by a calcareous cement. Further down the river, it is finer, and stated to contain minute fragments of shells. Below Sheergah, the country, as far as the Caspian, is an alluvial, muddy flat. This sea is stated to be fast filling up, and the disco- loured water of the streams, which flow into it, may be traced for five or six miles. Near the shore the water is so fresh that horses drink it ; and Dr. Bell says, that the shells are chiefly freshwater. Half imbedded in the banks of mud and sand are innumerable trunks of large trees which have been drifted down by the rivers. A con- glomerate similar to that at Dalee Chaee, was noticed at Karoo in ascending the Herza ; also below the small stream Abi Noor, at the foot of Demavend Peak. Lithographic Limestone. — A fine-grained limestone, used for litho- graphy in Teheran, forms a high ridge north of the city, the beds dipping to the north, and resting on serpentine, porphyritic claystone. 572 Geological Society. and porcelain stone. In connexion with a blue limestone, it extends over an immense tract to the N. and N.W. of Teheran, on the southern flank of the Elboorz Chain, where it generally rests upon shale and red sandstone, which is underlaid by a calcareous forma- tion, called by the author mountain limestone. To the east of Teheran, the lithographic stone extends nearly to the village of De- mavend. Sandstone and Coal. — Between Teheran and Demavend, a sand- stone of a coal formation is occasionally exposed ; and in the bed of the river, Dalee Chaee, are upraised beds of "altered shale, like coked coal." On the north side of the Elboorz Mountains, shale and sandstone, assigned to the same coal deposit, are exposed resting upon the limestone. At Abbassabad is a sandstone, but it is not stated whether it belongs to this formation. A sandstone resting on lime- stone occurs in the ravine through which the Heraz flows above Amol ; also on the summit of the limestone pass between Karoo and Bulkulum. About a mile below the latter village, a precipice 900 or 1000 feet high consists of perpendicular beds of coal and sandstone, but on the opposite bank of the river the sandstone strata are nearly horizontal. Limestone. — Strata, considered by Dr. Bell as the representatives of the mountain limestone, constitute the hills to the S.E. of Teheran, and overhang the ruined city of Rai. To the westward of Dema- vend, the range of mountains, both north and south of the road as far as the Caravanserai of Dalee Chaee, consist of the same limestone resting on trap. Above the Caravanserai of Ameenabad, it occurs rest- ing also on trap ; and the hills in the neighbourhood of the plain of Feroozkooh are similarly constituted. On the north side of the Elboorz chain — a coal-shale and sandstone rest on this limestone. Below Pul-i- Seff^eed, the Talar runs for a considerable distance through a gorge presenting perpendicular cliffs of beds of limestone and conglome- rate. Limestone, resting on trap, also occurs in the ravine south of Amol. In ascending the river beyond this ravine towards Karoo, the following section is exposed. Trap — limestone — sandstone — shale — indurated slate clay — buhrstone — sandstone — limestone — trap. Between Karoo and Bulkulum is a narrow and deep fissure through a mountain of limestone, capped by the coal strata ; and near the tomb of Em Zadeh Hashim, limestone again occurs resting on trap. Organic Remains. — In the superficial conglomerate near the Dalee Chaee Caravanserai, Dr. Bell observed portions of two small Ammo- nites imbedded in fragments of compact limestone, but he did not notice the same rock in situ*. Trap. — Greenstone, basalt, amygdaloid, porphyry, claystone, pitchstone, and serpentine, underlie the limestone at many places. Travertine. — Springs charged with calcareous matter were often ♦ Near the summit of the ridge of the Elboorz just below the snowline, south of the district Toonikaban, he found a limestone containing bivalve shells ; and near Bayazecd, in the neighbourhood of Mount Ararat, lime- stone inclosing corals and oysters, and resting on sandstone. / Geological Society, 573 noticed, and it is stated, that the preservation of the remains of Shah Abas's causeway is owing to the calcareous drippings from the mountain side. Siliceous globules are formed by a hot spring in the little capital of Usk. Thermal and Mineral springs occur near Usk. In conclusion the author says, that the ravines through which the rivers Talar and Herdz flow, are not due to denudation, but to rents ; and that though the ravines are narrow, it would be difficult to point out a spot, where the strata on the opposite sides correspond. He noticed along the course of the Heraz, numerous effects of violent modem earthquakes*. A paper was next read entitled " Notes on the Geology of the line of the proposed Birmingham and Gloucester Railway," by Mr. Frederick Burrf. The author of this communication was employed on the survey for the railway, and the following is a general summary of his observa- tions : — For the first 26 miles, or from Gloucester to within three miles of Worcester, the road passes over the lower lias shale, and for the re- mainder of the distance over red marl and red sandstone. The lias tract is generally flat, seldom exceeding 100 feet above the level of the sea ; but the red marl and sandstone rise considerably higher, and in that portion of the Lickey range intersected by the line of railway, the sandstone attains a height of about 600 feet above the same level. From the Lickey to Birmingham, the country forms an undulating table land, having a mean elevation of from 200 to 300 feet. The author gives numerous bore hole or shaft sections, made during the survey, and is thus enabled to show the nature of the formations in a district, otherwise concealed by its physical features or cultivated surface. Lias. — ^The lias strata belong solely to the lower shales, and consist of bluish or blackish slaty clay, containing thin beds of argillaceous limestone. Near the junction with the red marl, there is generally a thick deposit of whitish or yellowish clay, with numerous beds of rubbly limestone, usually blackish. Beds of a light colour, resem- bling lithographic stone, are exposed in quarries near the Plough, half way between Gloucester and Cheltenham, and white lias is stated to occur at the junction with the red marl near Crawl, four miles N.E. of Worcester. The junction of the red marl is also exhibited in numerous small quarries in the same neighbourhood, but the strata consist of the above-mentioned whitish or yellowish clay, and dark limestone. These junction beds are also exposed at Dunhamp- stead, three miles S.E. of Droitwich. Red Marl and Sandstone. — No difference was noticed in this for- mation from the characters already published. The marl is gene- rally red and brown, but it is occasionally variegated or streaked white, and sometimes it contains a thin bed of red sandstone. The * [We have here an additional instance of the connexion between earthquakes and lines of disturbance. — Edit.] f [See the President's Address, in our last number, p. 513.] 574? Geological Society, following section is given of the Droitwich brine pits. Red marl, with much water, 40 feet ; marl with gypsum, but no water, from 100 to 130 feet in different pits : rock salt, not penetrated through at the depth of 170 feet. A pit at the chemical and salt works at Stoke Prior, four miles north of Droitwich, was sunk to the depth of 460 feet, first through red marl with much water. 111 feet ; then red marl with gypsum, but no water, 195 feet ; and afterwards marl interspersed with salt and interstratified with four beds of rock salt, 10 feet, 64^ feet, 39 feet, and 30 feet thick, respectively. About two miles beyond Stoke Prior, the red marl is replaced by red sandstone. At the junction, the former becomes slaty and con- tains thin beds of sandstone, and the latter consists of a pale brown- ish or yellowish argillaceous sandstone. At Finstat, black coaly impressions were noticed. About a mile north of Bromsgrove, the argillaceous sandstone is succeeded by a bright red micaceous sand- stone. The rise of this rock to the surface was probably pro- duced by the elevation of the neighbouring Lickey range, as at Stoke Prior, distant only two miles, the sandstone was not reached at the depth of 460 feet. In the ascent of the Lickey, the surface con- sists of coarse quartzose gravel, derived from the upper part of the range. The summit level of the railway is near Barnes Green Farm, and it is 384 feet above the sea. At this point a shaft was sunk through the following strata : — Feet Inch. Gravelly sand 6 0 Hard coarse gravel 1 6 Fine gravel 1 0 Hard coarse gravel 8 0 Indurated red marl 2 0 Hard coarse gravel 11 0 Red sandstone 1 0 Hard conglomerate 20 6 51 0* Of these beds of gravel, the author considers only the uppermost as superficial gravel, and the remainder as belonging to the new red. To the north of the ridge, the bright red sandstone re-appears, dip- ping considerably to the east, and alternating with marl and impure siliceous limestone. About a mile from the Lickey, the red marl again constitutes the surface, and extends to Birmingham. Superficial Detritus. — ^I'he lias in the vale of Gloucester is covered by 8 or 10 feet of brownish, greyish, or mottled clay and loam, overlaid by thick deposits of sand and gravel, derived, in the neigh- bourhood of Gloucester, Cheltenham, and some other places, from the adjacent oolitic hills ; but near Bredon and to the north of that village, the detritus consists of siliceous sand and pebbles. ♦ In deep cuttings of the Worcester and Birmingham Canal, \\ mile south-east of this point, Mr. Burr noticed an anticlinal axis, denudated in the centre. The strata dipped south and north at considerable angles, and consisted of red marl overlying red and white sandstone. Geological Society. 575 Mineral Springs. — From information obtained during the survey, the author states, that at Walton, one mile east of Tewkesbury, a spring similar in properties to the Cheltenham waters, was found at the depth of 90 feet : that in the neighbourhood of Northway, weak brine springs have been discovered in the lias clay at the depth of 40 feet ; and likewise on DefFord Common. All these springs, Mr. Burr remarks, range N. and S. and in a line with the brine springs of Droitwich and Stoke Prior. Near Stoulton, five miles from Worcester, is a small, brackish marsh. In conclusion, the author expresses his hopes, that surveyors, em- ployed on similar investigations, will be induced to lay the results of their field work before the Society; and he acknowledges his great obligation to Capt. Morsoom, the superintending engineer of the line, for being permitted to malie free use of all the geological information, which he obtained during the discharge of his duties. A paper on " the Coast Section from White Cliff Lodge, one mile south of Ramsgate, to the Cliff's End, near the Station Brig in Pegwell Bay, Kent," by Mr. John Morris, was afterwards read.* The cliffs consist of the upper chalk for about f of a mile, and of *' the lower or sandy beds of the London clay " for the remainder of the distance. A capping of superficial detritus, of rubbly chalk, chalk flints, and loam, extends the whole way. The principal object of the communication is to describe a series of dislocations in the chalk, marked by shifts in a layer of tabular flints. 1. At 52 paces from the commencement of the section is a slight indication of a fault. 30 paces further the layer of flints is depressed at a fissure 4 feet, ditto ditto ditto ditto ditto ditto ditto 10. About 45 paces from the last depression, the vein of flint is brought within 8 feet of the beach, and it is in one place affected by a fault of !•§ feet. 340 Close to fissures 1 and 2, are indications of parts of the bed of flint not having been equally disturbed, as they preserve the same ho- rizontal range, while the portions on each side are depressed : a si- milar example of irregular movement occurs at number 5. Beyond the fault 10, the cliff recedes, forming a small cove, produced, the au- thor believes, by the action of the sea on a considerable disturbance in the strata, the minor faults being always accompanied at the foot of the cliff by a natural excavation or cave. Where the layer of flint re-appears, it is curved, and is afterwards traversed by three faults producing unequal depression, one of which is coincident with a vein of tabular flint ; beyond the Preventive Sta- * [See the President's Address, in our last number, p. 513.] 2. 30 paces fur 3. 31 ditto 4. 53 ditto 5. 33 ditto 6. 43 ditto 7. 30 ditto 8. 11 ditto 9. 12 ditto ditto 4 ditto 2 ditto 3 ditto 2 ditto 4 ditto slightly. ditto 1 576 Geological Society. tion is another depression of 5 feet, the upper part of the fissure being; filled with chalk rubble, sand and flint, and the bottom hollowed into a cave 10 feet high, and from 15 to 20 feet deep. At 10 yards from this point the flint layer dips beneath the beach. The chalk clilF continues for about 800 paces further, gradually decreasing in alti- tude, but capped by sandy loam and chalk rubble. Beyond this point, the tertiary strata commence, consisting, in the upper part, of 7 to 18 feet of sand and sandy clay, with occasional masses of sandstone and layers of shells ; and in the lower part of 7 feet of bluish clay, which also incloses shells. These strata are visible for about 570 yards, and then dip beneath the marshes. Mr. Morris considers them the equivalents of the beds between Reculver and Heme Bay, agreeing in position, mineral characters, and organic remains. They are overlaid by the same superficial detritus as the chalk. The destruction of the cliff^s is calculated to have been, until means were taken to defend them, at the rate of 3 feet annually. At the cove before-mentioned, the sea removed in 25 years, about 20* yards, including two cottages and a garden. The wells at the Preventive Station and Pegwell, are sunk about 30 feet, through loam and chalk. The water is 10 feet deep, but it is sometimes brackish, being aff^ected by the rise and fall of the tide. It is generally lowest after the tide has flowed one hour, and remains in that state about two hours, after which it rises. Whether this effect is connected with the faults in the cliffs, Mr. Morris doubts ; but he states, that a freshwater spring issues from the beach at low water, opposite the well at the Preventive Station. Jan. 31. — An extract was first read from a letter addressed by Sir John Herschel to Mr. Lyell, and dated Feldhausen, June 12, 1837. In former letters addressed to Mr. Lyell and Mr. Murchison, dated Feldhausen, Feb. 20, and Nov. 15, 1836, and read before the Society May 17, 1837*, Sir John Herschel first proposed his theory relative to the increment of temperature from below, which would be pro- duced in certain portions of the earth's crust by the partial distribu- tion of additional sedimentary matter over the bottom of the ocean ; and of the effects which would naturally result from this operation, pro- ducing the phsenomena of earthquakes, and elevation and depression of strata. In this letter he states, he was not then aware that Mr. Babbage " had speculated on that peculiar mutual re -action of the surface and the interior of the globe, and which must be called the secular vari- ation of the isothermal surfaces of the latter ;" nor was he aware of the notice in the Proceedings! of Mr. Babbage's paper on the Temple of Serapis, until his attention was recently called to it by Mr. Lyell and Mr. Murchison, but at the end of which notice a theory iden- tical in the leading point is given. With respect to the first development of the theory, Sir John Herschel says, ** the employment of the pyrometric expansion of * Proceedings of Geol. Soc. vol. ii. p. 548. [Or Lend, and Edinb. Phil. Mag. vol. xi. p. 212, 214.] t Proceedings, vol. ii. p. 72. [Or Lond. and Edinb. Phil Mag. vol. v. p. 213.] Sir J. Herschel on the Theot-y of Volcajiic Phccncmena, 577 rocks as a motive power was, I feel confident, suggested by some one (the name of Mitscherlich or Laplace is somehow connected in my memory with it) many years ago, certainly before 1833. As regards the course of my own ideas, it was simply this. When I first read your book I was struck with your views of the metamorphic rocks, and I began to speculate how and why the mere fact of deep burial might tend to raise the temperature to the required point. Three modes occurred : 1st. development of heat by condensation ; but this cause seemed somewhat feeble, and not very clear in its mode of action, since at every moment an equilibrium of pressure and resistance is established : 2nd. plunging down into an ignited pasty mass ; here, however, considering the excessive slowness of the process, it oc- curred to me that there would be plenty of time for the ignited matter below, not merely to divide its caloric with the newly superposed mass, but to take up fresh from below, and thus to establish a regular gra- dation of temperature from below upwards ; and this led to the 3rd and more general view of the matter, which is that of the variation of the isothermal surfaces, as stated in my former letters." It was, however, the perusal of Mr. Lyell's 4th Edition which led to the final development of the theory. Sir John Herschel then observes : " When people think inde- pendently at different times, and excited by different original sub- jects of consideration, bearing on one more general object, if their ideas converge towards one view of the matter, it is a proof, that there is something worthy of further inquiry; and if they think to any purpose, it is hardly possible but that many points will occur to the one which do not occur to the other ; and that so a theory may branch out and acquire a body much sooner than it would do by the speculation of one alone ; and indeed such is, in some degree, the case in the present instance. Babbage, for exam- ple, has speculated not only on the heaping on of matter in some parts, but on its abstraction in others as a cause of variation in the isothermal surface, and justly. It is the case of the algebraic passage from -|- to — passing through 0. In envisaging (as the French call it) the question algebraically, the cases could not be separated. Again, he has confined himself to the pyrometric changes in the solid strata, while I have left these out of view, and relied on what I think to be a far more energetic and widely acting cause — the variation of pressure, and the infinity of supports broken by weight, or softened by heat, to produce tilts. Both causes, however, doubtless act, and both must be considered in further detail. The former alone may account for the phsenomena of the Bay of Naples ; the latter must I think be called in to account for those of Scandinavia and Greenland, and of the Andes. " I would observe that a central heat may or may not exist for our purposes. It seems to be a demonstrated fact that temperature does, in all parts of the earth's surface yet examined, increase in going down towards the centre, in what I almost feel disposed to call a frightfully rapid progression ; and though that rapidity may cease, and the progression even take a contrary direction long before we reach Phil. Mag. S. 3. Vol. 12. No. 78. Suppl. July 1838. 3 A 578 Geological Society, the centre (as it might do, had the earth, originally cold, been as Pois- son supposes, kept for a few billions or trillions of years in a firma- ment full of burning suns, besetting every outlet of heat, and then launched into our cooler milky-way) ; still as all we want is no more than a heat sufficient to melt silex, &c., I do not think we need trouble ourselves with any inquiries of the sort, but take it for granted that a very moderate plunge downwards in proportion to the earth's radius, will do all we want*." A paper was next read, entitled " Description of the Insulated masses of Silver found in the mines of Huantaxaya, in the province of Tarapaca, Peru ;" by Mr. BoUaert, and communicated by Mr. Darwin, F.G.S. The mines of Huantaxaya are three leagues from the Port of Iqui- qui (lat. 21*> 13' S. long. 70« W.), and in a mountain-hollow 2800 feet above the level of the sea. This depression is bounded towards the west by a hill called Huantaxaya, 3000 feet above the sea level, or 200 feet above the hollow, and on the opposite side by a hill of si- milar height. The great mass of the mountain consists of a reddish, argillaceous limestone, but the escarpment, towards Iquiqui is co- vered with loose sand, and near the base, porphyiy and granite are visible. ^JThe limestone is traversed by numerous argentiferous and other veins, which range fromN.E. by E., to S.W. by W., but the mines of Huantaxaya are in a superficial detritus called Panizo. This deposit is from eighty to one hundred yards thick, and is composed of fragments of limestone not water- worn, and dried mud apparently derived from the same rock. It is divided into beds, some of which, called Sinta,are metalliferous, and others, called Bruto, are barren. The nodules of ore, to which the name of papa has been applied, from their resembling a potatoe in form, consist of pure silver, chloride, and other chemical compounds of silver, sul- phurets of copper and lead, and carbonates of copper. The papas are of all sizes, and some have produced 160 ounces of pure silver in a hundred pounds. One celebrated papa weighed about 900 pounds, and resembled in shape the top of a table. The miners believe, that each layer of Sinta has been derived from a particular vein in the limestone, and that they can determine to which vein a papa origin- ally belonged. The only instruments used in working the Panizo, are an iron bar six inches long and a small iron mallet. With these tools, the Pa- nizero rapidly advances in the soft materials, but rarely makes a larger excavation than is sufficient for his body to pass on hands and knees. In clearing out the contents of these honey-combed galleries, a hide-bag is strapped over the shoulders and under the arms; but in crawling through the narrower parts, the miner trans- fers the bag to one of his feet and drags it after him. The danger of working these unconsolidated beds is greatly en- hanced by frequent shoclfs of earthquakes. • [See the President's Address, and also the Proceedings of the Royal Institution, p. 519 and 533 of our last number.] Geological Society, 519 The following section of the principal shaft will illustrate the na- ture of the Panizo deposit. 1. Caliche. This bed contains near the surface a large quan- tity of common salt, and occasionally a few small papas are found in'it 28 yards. 2. Sinta Cenisaduj ash-coloured, with a few papas ^ 3. Caliche, or Bmto 12 4. Sintttf Tisa chiquita, a bed consisting of 96-4 white sand, "l 3-G sulphuric salts and water ; also a trace of muriatic salts. I -^ A few papas • J yards. 5. Bruto 4 6. Sinta cascajosa ^ 7. Sinta Tiquillosa t 8. Siiifa challosa \ 9. Bruto manto, many fossil shells i 10. Bruto conchado, shelly lay- er* ^ 11. Tisi chiquita, resembling number 4 t 12. Sinta Tiquillosa ^ 13. Bruto 4 14. Sinta Tiquillosa \ 15. Bruto 4 16. Sinta challosa \ 17. Sinta cascajosa, gravelly layer \ 18. Bruto conchado, shelly* \ 19. Sinta conchado, shelly*... 2 20. Sinta challosa ^ 21. Sinta conchado, shelly,* few papas yards. 22. Sinta cascajosa, gravelly layer 4^ 23. 2'isa grande, similar to 4. 6 24. Bruto J. 25. Sinta cascajosa, gravelly layer \ 26. Bruto i- 27. Sinta chadosa \ 28. Bruto ^ 29. Sinta harrosa, clayey layer j. 30. Tisa, similar to 4 \ 31. Bruto 6 32. Sinta cascajosa, gravelly layer ^ 33. Bruto ^ 34. Sinta chadosa !■ 35. Bruto 3 36. Sinta chadosa .4. 37. Bruto 1 38. Sinta barrosa, clayey layer ^ The layer 38 rests upon the limestone rocks. A paper was afterwards read " On the peat bogs and submarine forests of Bourne Mouth, Hampshire, and in the neighbourhood of Poole, Dorsetshire ;" by the Rev. W. B. Clarke, F.G.S.f The entrance of Bourne Mouth Valley is one of the many chines which intersect the tertiary strata between Poole Harbour and Christ Church Head, and the valley extends from the sea three and a half miles in a N. W. direction. About halfway, a fork diverges to the west, and this branch with the lower portion of the main valley is called Bourne Bottom, and the eastern branch of the fork, Knighton Bot- tom. In each valley is a small current, and their united waters form the brook at Bourne Mouth. At the head of Knighton Bottom is a peat bog, which contains trunks of oak, alder, birch, and beech trees, also hazel sticks and nuts, and fragments of bark, llie trunks of the trees lie in the direction of the valley, but the stools are firmly fixed upright in the peat. The wood when extracted is soft, but it becomes firm on exposure to the weather, and it is used for purposes of husbandry. The bark, especially that of the beech, re- • In these layers, fossil shells, derived from the limestone, are found, t [See the President's Address, in our last number, p. 513.] 3 A 2 580 Geological Society, tains its character unaltered. Tlie surrounding district is now ste- rile, and no oaks of equal size exist within many miles of Knighton Bottom, the neighbouring plantations being of very recent origin. Traces of fire and of the axe are said to have been noticed in the bog-wood. Ten feet of peat have been excavated, but the depth of the deposit is not known. The peasantry have a tradition, that the forest was burned down during the reign of Stephen, though Mr. Clarke conceives that its destruction was effected during the occu- pation of England by the Romans. At the head of Bourne Bottom there is also a peat bog, but it incloses only fir trees. The subma- rine peat and forest off the entrance of Bourne Mouth* contains fir, birch, and alder trees ; Mr. Clarke however considers that the two latter have been transported from the bog at the top of Knigh- ton Bottom. Some of the trees, as noticed by Mr. Lyell, are py- ritous, but the author of the paper is of opinion^ that they have been derived from the neighbouring cliffs of plastic sand, having observed in them, during the summer of 1837, a pyritous trunk. The present position of the forest, Mr. Clarke thinks is due to a subsidence and undermining of the strata, which supported it at a higher level. Other peat bogs are described on the north of Poole harbour, as between Sterte and Stanley green, at Hatch Pond, Creekmoor and Lytchett. At the first of these localities, in mailing an excavation to erect a dyke, the workmen found beneath the alluvial soil, gra- vel, then peat, and afterwards oaks and alders which rested upon mottled clay. The sea, at all states of the tides, overflowed this inlet previously to the erection of the dyke ; and the position of the forest Mr. Clarke assigns to an undermining of the strata on which it rested. At Hatch Pond, about two miles north of Poole, in the direction of Winboum, is an extensive depression through which a brook of some volume flows, and has produced an immense accumulation of peat. This bog communicates with Poole Harbour by a succession of marshy grounds ; the whole of which Mr. Clarke conceives were once covered by the sea, as they present phenomena similar to those exhibited at Tottenham, with the exception that no trees have been observed. A branch of a Roman road meets the present high- way just upon the edge of the depressed area, and the author infers that that point was, in the time of the Romans, the water head of the bay, though it is now three or four furlongs Nearer Poole. Creekmoor. Another tract of low marshy ground, with a peat-bog * An account of this submarine fir-wood was first given by Mr. Lyell in the 4th edition of the Principles of Geology (1835), from information com- municated by Mr. Charles Harris. The present submerged position was ex- plained on the belief, that as the sea is encroaching on the shore, the Bourne Valley may once have extended further; and that its extremity consisted as at present of boggy ground, partly clothed with fir-trees; that the sea laid bare at low tide the sandy foundations, which being undermined by streams of freshwater, several of which burst forth in different parts of the existing beach, the matted superstratum of vegetable matter sank down below the levjl of the sea.— Vol. iii. p. 276. Mr. Hamilton on the Geology of part of Asia Minor, 581 containing fir trees, occurs at Creekmoor bridge on the north side of Holes Bay. In draining it, the workmen, about four feet from the surface, tapped a spring which flows with great violence and throws up white sand. Lytchett. At various places in this parish, peat bogs and buried trees occur, particularly at Bulbury Bay. They are, however, consider- ably above the level of the sea ; but on the north east side of Lytchett Bay, at the extremity of the canal from the clay works, is a subsided peat bog thirty feet thick, containing trees. It rests upon mottled clay, and is overlaid by nine or ten feet of clay and sand which are constantly covered by two feet of water. In the pits where the subjacent mottled clay is excavated, springs of great volume burst forth whenever the main body of water is tap- ped, and the author is of opinion that this subterranean stream may have caused the subsidence of some of the peat bogs, in consequence of its undermining action. In alluding to the accumulations of mud in Poole Harbour, the author states, that in digging a well in West Street in the town of Poole, a mass of sea- weed was found, with remains of an ancient en- bankment at the depth of six feet, and a furlong from the present tigh water mark. Feb. 21.* — A paper " On part of Asia Minor," by William John Hamilton, Esq., Sec. G.S., was read. In this paper, the author gives an account of the geological struc- ture of the country from the foot of Hassan Dagh, a few miles S.S.E. of Akserai (lat. 38° 20' N., long, about 34° E.), to the great salt lake of Toozla or Kodj-hissar, and thence eastwards to Csesarea and Mount Argseus. The formations, noticed by Mr. Hamilton, are trachytic conglo- merates, considered by him one of the oldest formations of the country ; a system of highly inclined beds of red sandstone, conglo- merates and marls, which rest upon the trachytic conglomerate, and are apparently connected with the saliferous deposits of the country, though the author did not observe any beds of salt in the sandstonef ; a limestone belonging to the vast, calcareous, lacustrine formation of the central part of Asia Minor ; a great system of vol- canic tuffs, trachytes and basalts, apparently of comparative modern origin ; and a grey granite which is newer than the sandstone, as it penetrates and disturbs that formation near Kodj-hissar ; but pebbles of a grey granite identical in composition also occur in the conglo- merate. Hassan Dagh, upwards of 8000 feet above the sea, consists en- tirely of trachyte, and trachytic and porphyritic conglomerates, and rises from the eastern termination of a great calcareous plain. Several volcanic cones, composed of trachytic conglomerates and • [The Anniversary Proceedings of Feb. 16, will be found in our two preceding numbers, p. 433, 508, et seq.l t The extensive beds of rock salt on the borders of Pontus and Galatia, occur in troughs or small basins resting upon the perpendicular edges of a red and brown sandstone conglomerate. 583 Geological Society, scoriae, occur near the base on the S.S.W. and N.W. sides. All the latter, with the exception of one, are in the present valley, and below the tufaceous beds which cap the hills on its north side, and were, therefore, produced subsequently to the excavation of the valley. From one of them a considerable stream of black, vesicular lava proceeds, and encircles some of the smaller cones. From the foot of Hassan Dagh to the great salt lake of Kodj- hissar, the road traverses a plain, bounded on the south by low hills of the lacustrine limestone ; and on the north by hills having narrow peaks and steep escarpments, of red and yellow sandstone, sometimes associated Avith calcareous conglomerates, sand and marl, and capped towards the east and north-east by beds of tuff and a white pu- miceous rock, which passes into trachyte. Still further east, is a hill in which the sandstone rests upon a trachytic conglomerate. The phenomena presented in this district, the author conceives, indicate the following operations : — 1. The irruption of the trachyte, from which the trachytic con- glomerate was formed. 2. The deposition of the sandstones, conglomerates and marls. 3. The ejection of the igneous matter constituting the overlying beds of volcanic tuff and pumiceous rock. 4. The excavation of the valley. 5. The formation of the volcanic cones at the foot of Hassan Dagh. The water of the salt lake of Kodj-hissar is so highly charged with saline matter, that no fish can live in it ; and if the wings of a bird touch it, they become instantly stiff and useless with incrus- tation. Mr. Hamilton could not ascertain the exact dimensions of the lake, but he was informed, that it is about thirty hours or leagues in circumference. The bottom is a soft mud, incapable of supporting the slightest weight ; but at the part examined by the author, a thick, solid crust of salt, which bore the weight of a horse, rested upon the soft mud, and was covered by about six inches of water, which he was informed would be dried up in another month. The sandstone formation extends beyond the village of Kodj- hissar, towards the N.N.W., dipping in the same direction. It is penetrated near the town by a mass of finely-grained, grey granite, which also sends veins into the sandstone, and produces an anti- clinal inclination, the dip towards the south being 80°. In the sandstone conglomerate of the. neighbourhood, Mr. Hamilton, how- ever, noticed pebbles of a grey granite similar in composition to that of the protruded mass. About a mile N.W. of Kodj-hissar are detached portions of the horizontal white limestone, either resting unconformably against the sandstone, or filling up irregularities in its surface. In some places it caps the hills, which flank the valley a little to the north of the village. The only fossils noticed in the sandstone, were impressions re- sembling fucoids, and similar to those found in the Alpine limestone near Trieste. Mr. Hamilton on the Geology of part of Asia Minor, 583 The author then describes the structure of the country between Kodj-hissar and Csesarea, a distance of about 108 miles. It consists of the same sandstone system containing gypsum, and occasionally overlaid by horizontal beds of the lacustrine limestone and volcanic tuff; but the latter constitutes likewise large districts, the fundamental rock of which is not visible. Granite forms a range of hills thirty miles in extent, about midway between Kodj-hissar and Sari-kara- man, and is traversed in one place by a N.N.E. and S.S.W. dyke of claystone porphyry: granite occurs also between the latter towa and Tatlar. Trap and trachyte were noticed at several places, like- wise serpentine and greenstone near Sari-karaman; and basaltic rocks form table lands overlying the volcanic tuff near Tatlar and Baktash ; and close to Nembscheher beds of basalt alternate with the vol- canic tuff. To the east and north-east of Tatlar the author re- marked several volcanic hills, from which streams of basalt or lava appear to have flowed. To the south-east of the village he also saw a stream of a more recent date than that which caps the neigh- bouring hills; for it not only flows at a lower level, but below the steep escarpments of the older basalt. In the ravine near Tatlar, and in the vallies of Utch-hissar and Urjub, the tuff has been worn into cones from 150 to 300 feet high. They are principally detached from the sides of the vallies, but are connected at the base ; and are in some places so numerous and close together, that they resemble at a distance a grove of lofty cypresses. Where the cones occur on the sides of the vallies, they exhibit every stage of development, from the first indication of a mound near the summit of the slope, to the full-formed cone at the bottom. In the valley of Urjub some of them are capped by a mass of hard rock, which projects like the head of a mushroom. The production of these cones the author ascribes to the action of running or atmospheric waters. One of the principal objects of Mr. Hamilton's visit to this part of Asia Minor, was to ascend to the summit of Mount Argaeus, which had not previously been reached by any traveller. This mountain rises abruptly from the alluvial plain of Caesarea, sending out prolongations and spurs into the plain which stretches to the north, between Injesu and Caesarea ; but it is connected at its eastern base with other ranges of mountains. It rises, like Has- san Dagh, to a single peak, and it resembles in outline, the summit of Ararat. The highest part consists of a reddish brecciated and scoriaceous conglomerate, full of fragments of trap and porphyritic trachyte, and may be said to be the point of junction of two enor- mous, broken craters, one of which opens to the N.E., the other to the N.W., the steep sides of which are covered to the north with eternal snow for 2000 or 3000 feet below the summit. The height of the mountain was ascertained by Mr. Hamilton to be about 13,000 feet, the following being the results of his observations. By barometer 13,293 By angle of elevation from the Greek Convent 13,242 By angle of elevation from Kara-hissar 12,80i> 584 Geological Society, A little below the summit, on theS.E, side, rugged, serrated ridges rise through the snow, some of them consisting of a compact tra- chytic rock, with a highly conchoidal fracture, resembling that of hornstone ; but others are composed of poi^ihyritic trachytes of va- rious colours and textures. Near the foot of the great cone, on the S.E., W., and N. sides, rise numerous smaller ones of pumice and lapilli, from some of which on the N.W. side, streams of basalt or lava may be traced. In conclusion, the author expresses his regrets, that the want of organic remains prevents him from determining the comparative an- tiquity of the formations, with respect to those in Europe. In only one instance, the fucoid impressions near Kodj-hissar, did he ob- serve a trace of an organic body in the sandstone ; and the only occurrence of fossils in the limestone series which he noticed, was in the neighbourhood of Sevri-hissar W.S.W. of Angora, where he discovered, in the upper beds of the formation, Limnea and Planorbis. March 7. — A notice was first read, on some remarkable dikes of calcareous grit at Ethie, in Ross-shire, by Hugh Edwin Strickland, Esq., F.G.S. lliese dikes, which traverse the lias schist, are displayed only at low water. Two of them are parallel to the strata of schist ; but another, which sends off branches in various directions, is in no part of its course parallel to those strata. Their thickness varies from one to three feet ; but that of some of the lateral branches does not exceed three inches. They exhibit no variation in texture or com- position, and show no signs of lamination, but are frequently frac- tured transversely to their direction. The transition from the dike to the lias shale is immediate ; no change being apparent in the lat- ter at the point of junction. The shale, from its greater softness, has been removed between the dikes, leaving them like walls from one to three feet in height. These dikes, and similar ones in other places, were noticed by Mr. Murchison, in his examination of the coast of Scotland, in 1826. By what means the dikes were produced, the author does not ven- ture to inquire ; his only object being to draw the attention of geo- logists still further to them. A paper, on the connexion of certain volcanic phsenomena, and on the formation of mountain- chains and volcanos, as the effects of continental elevations, by Charles Darwin, Esq., Sec. G. S., was then read. The author first gave a detailed account of the volcanic phsenomena, which accompanied the earthquake that destroyed Concepcion on the morning of the 20th of February, 1835; and then deduced from volcanic pha^nomena, certain inferences with respect to the formation of mountain-chains, and continental elevations. In describing the phaenomcna of the earthquake of 1835, Mr. Darwin quotes the published accounts by Captain Fitzroy* and Mr. * Journal of the Royal Geographical Society, vol. vi., p. 319, 1836. Mr, Darwin on certain Volcanic Phenomena, 585 Caldcleugh*; likewise communications received by him from Mr. Douglas, a resident on the island of Chiloe. A few days after the earthquake, several volcanos within the Cor- dilleras, to the north of Concepcion, though previously quiescent, were in great activity. It is doubtful, however, if the volcano of Antujo, in nearly the latitude of Concepcion, was affected, while the island of Juan Fernandez, 360 miles to the north-east of the city, was apparently more violently shaken than the opposite shore of the main land. Near Bacalao Head, a submarine volcano burst forth in sixty-nine fathoms water, and continued in action during the day as well as part of the following night. That island was also affected in a remarkable manner, by the earthquake which overthrew Con- cepcion in 1751. In Concepcion, the undulations of the surface appeared, to the in- habitants, to proceed from the south-west; and this direction was likewise inferred, from the effects observed in the buildings; for those walls, which had their extremities towards the point of dis- turbance, remained erect, though much fractured ; whilst those (and the streets cross each other at right angles) which extended parallel to the line of the vibration, were hurled to the ground. This was strikingly exemplified in the cathedral, where the great buttresses of solid brick-work were cut off, as if by a chisel, and thrown down ; while the wall, for the support of which they had been built, though much shattered, remained standing. In Chiloe, south of Concepcion, the shocks were very severe, but they entirely ceased in about eight minutes. The motion, as de- scribed by Mr. Douglas, was horizontal, and similar to that of a ship going before a high, regular swell ; from three to five shocks being felt in a minute ; and the direction being from N.E. to S.W. Forest- trees nearly touched the soil in these directions ; and a pocket com- pass placed level on the ground vibrated, during the violent shocks, two points to westward, but only half a point to eastward ; and during the minor shocks the needle pointed north. At Calbuco, a village on the mainland opposite the northern extremity of Chiloe, as well as at Valdivia, between Chiloe and Concepcion, the earthquake was much less severely felt ; and near MellipuUi, in the Cordilleras (not far from Calbuco), not at all. The volcano of Villareca, near Valdivia, which is said to be more frequently in irruption than almost any other in the chain, was not the least affected ; though the volcanos of central Chili are stated by Mr. Caldcleugh to have been seen, some days af- terwards, in great activity. Several of the culminating points of the Cordillera in front of the island of Chiloe, exhibited increased energy during the earthquake, and immediately after it. During the shocks, Osomo, which had been in activity for at least forty- eight hours previously, threw up a thick column of dark blue smoke ; and di- rectly it had passed away, a large crater was seen forming in the S.S.E. side of the mountain; Minchinmadiva also, which had been in its usual state of moderate activity, commenced a fresh period of • Phil. Trans., 1836; Part I. p. 21. [An abstract of Mr. Caldcleugh 's' paper appeared in, Load, and Edinb. Phil. Mag. vol. viii. p. 148.] 586 Geological Society, violence. At the time of the principal shock, the Corcovado was quiet ; but when the summit of the mountain was visible a week af- terwards, the snow had disappeared from the north-west crater. On Yntales, to the south of the Corcovado, three black patches, resem* bling craters, were observed above the snow-line after the earthquake, though they had not been noticed previously to it. During the re- mainder of the year, the whole of the volcanic chain, from Osomo to Yntales, a range of 150 miles, exhibited, at times, unusual activity. On the night of the 11th of November, Osomo and Corcovado threw up stones to a great height ; and on the same day, Talcahuano, the port of Concepcion, 400 miles distant, was shaken by a very severe earthquake; and on the 5th of December the whole summit of Osomo fell in. After these details of more particular phsenomena, Mr. Darwin alluded to the great areas over which earthquakes have been simul- taneously felt ; but he added, it is impossible even to guess through how wide an extent, in the subterranean regions, actual changes may have taken place. In order to enable the reader, who may be more familiar with European than South American geography, to comprehend the vast surface which was affected by the earthquake of February 1835, he stated, that it had a north and south range, equal in extent to the distance between the North Sea and the Mediterra- nean; that we must imagine the eastern coast of England to be permanently raised ; and a train of volcanos to become active in the southern extremity of Norway ; also that a submarine volcano burst forth near the northern extremity of Ireland; and that the long dormant volcanos of the Cantal and Auvergne, each sent up a column of smoke. The contemplation of volcanic phsenomena in South America, has induced the author to infer, that the crust of the globe in Chili rests on a lake of molten stone, undergoing some slow but great change ; for if this inference be denied, he says, the only alternative is, that channels from the various points of eruption must unite in some very deeply-seated focus. This conclusion, however, he doubts, on ac- count of the union of the different trains of volcanos on the one line of the Cordillera, and more especially as many hundred square miles of surface in Chili have been elevated during the same earthquake. Moreover, these elevations have acted within a period geologically recent, throughout the whole, or at least the greater part, of Chili and Peru, and have upraised the land several hundred feet. He is further of opinion, that the shocks coming from a given point of the compass, and the overthrow of the walls, according to their position with respect to this point, prove that the vibrations do not travel from a profound depth, but are due to the rending of the strata not far below the surface of the earth. In a geological point of view, the author conceives, the three classes of phaenomena exhibited during this earthquake of February 1835, viz. a submarine outburst — renewed volcanic activity, simultaneously at distant localities — and a permanent elevation of the land, to be of the greatest importance, as forming parts of one great action, and Mr. Darwin on certain Volcanic PhcEnomena. 587 being the efFects of one great cause, modified only by local circum- stances. Mr. Darwin further observed, that, as the volcanos near Chiloe commenced, at the moment of the shock, a period of renewed activity, which lasted throughout the following year, the motive power of these volcanos (as well as of the submarine outburst near Juan Fernandez) must be of a similar nature with that, which, at the same instant, permanently raised another part of the coast ; and he therefore concluded, that no theory of the cause of volcanos, which is not applicable to continental elevations, can be considered as well- grounded. Mr. Darwin then offered some remarks on the two tables pub- lished by Humboldt, of the great earthquakes which affected, in 1797 and 1811, so large portions of America; and he is of opinion, that a repetition of the coincidences can alone determine how far the in- creased activity of the subterranean powers, at such remote points, was the effect of some general law, or of accident. He likewise dis- believes, that periodical eruptions, as those of Coseguina, in 1709 and 1809, or of earthquakes, as the shocks felt at Lima on the 17th of June 1578, and the 17th of June 1678, are more than accidental agreements. He also gave a table of the volcanic phsenomena in South America in 1835 ; and concluded, that it is probable that the subterranean forces manifest, for a period, their action, beneath a large portion of the South American continent, in the same inter- mittent manner as they do beneath isolated volcanos. In the latter table, Mr. Darwin pointed out the case of Osorno, Aconcagua, and Coseguina, (the first and last being 2700 miles apart,) which burst into sudden activity early on the morning of June 20th, 1835 ; but he hesitated to assent to there *being any necessary connexion between them. He further remarked, that if such simultaneous outbursts had been observed in Hecla and vEtna, points unconnected by any uniformity of physical structure, it would be doubtful how far they would have been worthy of consideration ; but in South America, where the volcanic orifices fall on one line of uniform physical struc- ture, and where the whole country presents proofs of the action of subterranean forces, he conceives it ceases to be improbable, to any excessive degree, that the action of the volcanos should sometimes be absolutely simultaneous. The author then briefly described the groups into which the vol- canic vents of the Cordilleras have been divided. The most south- ern extends from Yntales to the volcanos of central Chili, a dis- tance of nearly 800 geographical miles ; the second, from Arequipa to Patas, rather more than 600 miles ; the third, from Riobamba to Popayan, a distance of about 300 miles ; and to the northward, there are in Guatimala, Mexico, and California, three groups of vol- canos separated from each other a few hundred miles. That the vents in each of these groups are connected, the author has little doubt ; but that the groups are united in one system, there are less catisfactory means of proving. Mr. Darwin next considered the nature of the earthquakes which occur at irregular intervals on the South American coast. He is 588 Geological Society, perfectly convinced, from the numerous points of analogy which ex- ist between these phaenomena and simple eruptions, that they belong to the same class of events ; but he makes this distinction, that earthquakes, unaccompanied by eruptions at the chief point of dis- turbance, are followed by a vast number of minor shocks. These, he believes, indicate a repeated rending of the strata beneath the surface ; whereas, in an ordinary eruption, a channel is formed du- ring the first outburst. Among other phaenomena belonging to earthquakes, Mr. Darwin alluded to their affecting elongated areas. Thus the shock in Syria, m 1837, was felt on a line 500 miles in length by 90 in breadth; and those in South America are felt along 800 and 1000 miles of coast, but are on no occasion transmitted across the Cordillera to a nearly equal distance; and, as a consequence, the inland towns are much less affected than those near the coast. He does not con- ceive, however, that the disturbances proceed from one point, but many ranged in a band, otherwise the linear extension of earth- quakes would be unintelligible. For instance, in 1835, the island of Chiloe, the neighbourhood of Concepcion and Juan Fernandez were all violently affected at the same time. The last consideration which Mr. Darwin entered upon indicating the cause of earthquakes, is, that in South America they have been generally accompanied by elevation of the land ; though it is not a necessary concomitant, at least to a perceptible amount. But he especially observed, that, as at Concepcion, during the few days suc- ceeding the great shock, several hundred earthquakes, of no incon- siderable violence, were experienced, whilst the level of the ground in that part of the coast certainly was not raised by them (but after the interval of a few weeks, it stood lower,), there is a clear indica- tion of some cause of disturbance, independent of the uplifting of the land in mass. In summing up the evidence of phaenomena accompanying earth- quakes, the author is of opinion that the following conclusions may be drawn : — 1st. That the primary shock of an earthquake is caused by a vio- lent rending of the strata, which, on the coast of Chili and Peru, seems generally to occur at the bottom of the neighbour- ing sea. 2ndly. That this is followed by many minor fractures, which, though extending upwards, do not, except in submarine vol- canos, actually reach the surface. 3dly. That the area thus fissured extends parallel, or approxi- mately so, to the neighbouring coast mountains. Lastly. That the earthquake relieves the subterranean force, pre- cisely in the same manner as an eruption through an ordinary volcano*. * [Those who have perused Sir John F. W. Herschers views on the theory of volcanic action (Babbage's Ninth Bridgewater Treatise, sec. edit, pp. 230-240,) will not fail to recognise the close accordance with them, of Mr, Darwin on certain Volcanic Phcenomena, 589 The author afterwards discussed the nature and phaBUomena of mountain chains ; and stated his belief, that the injectipn, when in a fluid state, of the great mass of crystalline matter, of which the axis is generally composed, would relieve the subterranean pressure in the same manner as an ejection of lava or scoria ; and that the dislocation of the strata would produce horizontal vibrations through the surrounding country. In drawing this parallel, he also stated his belief, that the earthquake of Concepcion marked one step in the elevation of a mountain chain ; and he adduced, in support of this opinion, the fact observed by Capt. Fitzroy, that the island of Santa Maria, situated 35 miles to the south-west of that city, was elevated to three times the height of the upraised coast near Concepcion ; or at the southern extremity of the island, eight feet ; in the middle, nine feet ; and at the northern extremity, upwards of ten feet ; and that at Tubal, to the south-east of Santa Maria, the land was raised six feet* ; this unequal change of level indicating, in his opinion, an axis of elevation in the bottom of the sea, off the northern end of Santa Maria. Mr. Darwin then alluded to Mr. Hopkins's Researches in Physical Geology ,t where it is demonstrated, that if an elongated area were elevated uniformly, it would crack or yield parallel to its longer axis ; and that if the force acted unequally, transverse cracks or fis- sures would be produced, and that the masses, thus unequally dis- turbed, would represent the irregular outline of a mountain- chain. He further added, that if the force should act unequally beneath the area simultaneously affected, various fissures would be formed in different parts, having different directions, and thus give rise, at the same moment, to as many local earthquakes. The author believes, that this view will more readily explain intermediate districts being little disturbed (as Valdivia in 1835, and in cases alluded to by Hum- boldt,) than the supposed inertness of intermediary rock in con- veying the vibrations from a deeply- seated focus. If the preceding theory of the cause of earthquakes be true, Mr. Darwin said, we might expect to find, that the many parallel ridges of which the Cordillera is composed, were of successive ages. In Central Chili, the only portion examined by him, this is the case, even with regard to the two main ridges ; and some of the exterior lines of mountains appear, likewise, to be of subsequent dates to the cen- tral ones. The contemplation of these phsenomena led him, while in South America, to infer, that mountain- chains are only subsidiary, and attendant operations on continental elevations. The conclusion, that mountain- chains are formed by a long suc- cession of small movements, the author conceived may be arrived at by theoretical reasoning. The first effect of disturbing agents, Mr. Hopkins has shown, is to arch the crust of the earth, and to traverse the phsenomena above described and the conchisions above drawn by Mr. Darwin. — Edit.] ♦ Journal of the Royal Geographical Societj^, vol. vi. p. 327. t [See Lend, and Edinb. Phil. Mag. vol. viii. p. 227, et seg.'] 590 Geological Society, \ it by a system of parallel but vertical fissures ; and that subsequent elevations and subsidences of the disjointed masses would produce anticlinal and synclinal lines. In the Cordillera, the strata in the central parts, are inclined at an angle commonly exceeding 45°, and are very often absolutely vertical, the axis being composed of granitic masses, which, from the number of dikes branching from them, must have been fluid when propelled against the lower beds. How then, he asked, could the strata have been placed in a highly inclined and often vertical position, by the action of the fluid rock beneath, with- out the very bowels of the earth gushing out ? If, on the other hand, it be supposed that mountain-chains were formed by a succession of shocks similar to those which elevated Concepcion, and after long intervals, time would be allowed for the injected rock to become solid, as well as the upper part of the great central mass. Thus, by a succession of movements, the strata might be placed in any posi- tion ; and the crystalline nucleus gradually thickening, would pre- vent the surface of the surrounding country being inundated with molten matter. In crossing the Andes, Mr. Darwin was surprised at finding, not one great anticlinal line, but eight, or more ; and that the rocks com- posing the axes were seldom visible, except in denuded patches in the vallies. This circumstance, he conceives, must be due to the thickness of the upheaved strata being equal, or nearly so, to the average distance of the anticlinal from the synclinal lines. For in that case, the masses of strata, when placed vertically, would occupy, or rest on, as great an horizontal extent, as they did before they were dis- turbed. In the central ridges of the Cordillera, there are masses of com- pact, unstratified rocks, half again as lofty as ^tna ; and these, he believes, for the reasons before stated, were formed by the gradual cooling of the subjacent fluid mass ; afterwards slowly elevated to the present position, by the injection of molten matter at nearly as slow a rate, as we must suppose the innumerable layers of vol- canic products, of which the Sicilian mountain is formed, have been ejected. In conclusion, Mr. Darwin repeated the argument, that moun- tain-chains and volcanos are due to the same cause, and may be considered as mere subsidiary phsenomena, attendant on continental elevations ; — that continental elevations, and the action of volcanos, are phsenomena now in progress, caused by some slow but great change in the interior of the earth ; and, therefore, that it might be anticipated, that the formation of mountain-chains is likewise in pro- gress ; and at a rate which may be judged of, by either actions, but most clearly by the growth of volcanos. March 21st. — A paper was first read, on the Dislocation of the Tail, at a certain point, observable in the skeletons of many Ich- thyosauri, by Richard Owen, Esq., F.G.S., Hunterian Professor to the Royal College of Surgeons, London. Mr. Owen commences his observations by referring to the skele- ton of the existing cetacea, and pointing out how slight is the indi- Prof. Owen on the supposed Caudal Fin of the Ichthyosawus. 591 cation afforded by the caudal vertebrae of the large terminal fin, which forms, in that class, so important an organ of locomotion ; and the improbability that its presence would have been suspected, had the cetacea been known only by their fossil remains, in consequence of the fin having consisted entirely of decomposable and unossified material. He states, that the flattened shape of the terminal vertebrae, which gives the only indication of the horizontal fin — and which cha- racter is not present in all the cetacea — ^is not recognisable in the skeletons of the Ichthyosauri and Plesiosauri ; but he proceeds to describe a condition of the tail in the skeletons of the Ichthyosauri, which, he conceives, affords an indication of a structure in the ex- tinct animal, analogous to the tegumentary fin of the cetacea, and which has not been suspected by the authors of the conjecturally- restored figures of the Ichthyosauri, already published. The condi- tion alluded to, is described as an abrupt bend of the tail about one- third of its whole length distant from the end y and at the thir- tieth caudal vertebra in the Ichthyosaurus communis', the broken portion continuing, beyond the dislocation, as straight as in the part which precedes it. As there is no appearance of a modification of structure in the dislocated vertebrae, indicative of the tail having possessed more mobility at that point than at any other; and as the dislocation has taken place at the same point in seven specimens ex- amined by the author, he conceives that it must be due to some cause operating in a peculiar manner on the dead carcase of the Ichthyosaurus, in consequence of some peculiarity of external form, while it floated on the surface of the sea. A broad tegumentary fin, composed of dense but decomposable material, might have been attached to the terminal portion of the tail ; and such a fin, either by its weight, or by presenting an ex- tended surface to the beating of the waves, or by attracting preda- tory animals of strength sufficient to tug at, without tearing it off, would occasion, when decomposition of the connecting ligaments had sufficiently far advanced, a dislocation of the vertebrae imme- diately proximate of its point of attachment. The two portions of the tail, with the rest of the skeleton, would continue to be held to- gether by the dense exterior integument, until the rupture of the parietes of the abdomen, at some yielding point, had set free the gases generated by putrefaction ; and the skeleton, having undergone cer- tain partial dislocations, from the decomposition of the more yield- ing ligaments, would subside to the bottom, and become imbedded in the sedimentary deposits, exhibiting the fracture of the tail al- luded to. With respect to the relative position of this conjectured, caudal, tegumentary fin of the Ichthyosaurus, Mr. Owen cannot perceive any indication of its horizontality in the forms of the vertebrae, which he supposes to have supported it ; and he regards the super- addition of posterior paddles in these air-breathing marine animals, as a compensation for the absence of that form of fin, which is so essential in the cetacea, for the purpose of bringing the head to the 5d2 Zoological Society, surface of the sea to inhale the air. On the other hand, a vertical caudal fin seems especially required by the short-necked and stiff- necked Ichthyosauri, in order to produce, with sufficient rapidity, the lateral movements of the head, which were needed by those pre- datory inhabitants of the ancient deep ; while, in the Plesiosaurus , such a fin would be unnecessary, in consequence of the length and mobility of the neck ; and Mr. Owen concludes, by stating, that in those skeletons of Plesiosauri in which the tail is perfect, it is straight, and presents no indication of the partial fracture or bend, which is so common in the tails of Ichthyosauri, Figures of the tails of five specimens oi Ichthyosauri, now in Lon- don, accompanied the Note ; the subject of which was also illus- trated by a sixth skeleton of an Ichthyosaurus on the Table, the property of Sir John Mordaunt, Bart. A paper was commenced, on the Primary Formations of England, by the Rev. Adam Sedgwick, V.P.G.S.; Woodwardian Professor in the University of Cambridge, &c. ZOOLOGICAL SOCIETY. [Continued from p. 531.] July 11, 1837. — A letter was read from Mr. Hugh Cuming, Cor- responding Member, dated Manilla, December 24th, 1836, addressed to the late Secretary, E. T. Bennett, Esq. Mr. Cuming states in this letter that he is actively engaged in his favourite pursuit, that of collecting objects in various depart- ments of natural history, and he speaks very highly of the assistance afforded him by the public authorities at Manilla in prosecuting his researches. This letter was accompanied by a large box of skins of birds and quadrupeds, part of which were a donation to the Society. A letter was read from Keith Edward Abbott, Esq., Correspond- ing Member, dated Erzeroum, May 12, 1837, stating that he had dispatched a box of bird-skins for the Society. Mr. Martin then laid before the meeting the following observa- tions on the Proboscis Monkey, or ' Guenon h long nez.* (Simia Na- salis.) The genus Nasalis, of which the " Guenon alongnez" of BufFon, (suppl. vii.,) or Proboscis Monkey of Shaw, is the type, was founded by GeofFroy St. Hilaire in his * Tableau des Quadrumanes,' published in the ' Annales du Museum d'Histoire Naturelle' for 1812. In this outline of the Simiada, the genera Semnopithecus and Cercopithecus are blended together under the latter title ; but from this group are excluded two monkeys, the Douc, constituting the type of the genus Pygathrix (Lasiopyga, 111.) and the " Guenon a long nez". With respect to the genus Pygathrix or Lasiopyga, founded upon the al- leged want of callosities, most naturalists I believe, (aware of the error committed both by GeofFroy and Illiger, in describing from an imperfect skin,) have regarded it as merging into the genus Semno- pithecus, at least provisionally, until the internal anatomy of its as- sumed representative be known. The characters of the genus Nasalis, formed for the reception of Zoological Society. 593 the " Guenon d, long nez," (Simia Nasica, Schreb. Cercopithecus lar- vatus, Wurmb,) are laid down as follows : "Muzzle short, forehead projecting, but little elevated ; facial an- gle SC ; nose prominent, and extremely elongated ; ears small and round ; body stout ; cheek-pouches, anterior hands, with four long fingers, and a short thumb, ending where the index finger begins ; posterior hands very large, with fingers stout, especially the thumb ; callosities large ; tail longer than the body." At a subsequent period, however, in his ' Cours de I'Histoire Na- turelle,' published 1828, Geoflfroy, adopting the genus Semnopithecus, established by Fred. Cuvier, places the " Guenon a long nez," within its limits, doubtfully it is true, and with the acknowledgment that his genus Nasalis has not been generally adopted, but at the same time with a bias in its favour; for observing that the manners of these monkeys are those of the Semnopitheci, he adds, — *' Cependant, il ne nous parait encore demontre que le singe nasique soit une veri- table semnopitheque, et il est fort possible que lorsque I'espece sera moins imparfaitement connue, on soit oblige de retablir le genre Nasalis, dans lequel on I'isolait autrefois, mais que n'est pas ete ad- mis par la plupart des auteurs modernes." Setting aside the singular conformation of the nose, so remarkable in the Simia Nasalis, its external characters are not different from those of the Semnopitheci in general, and it is to be observed that in a second species, lately added by Mr. Vigors and Dr. Horsfield, under the title of Nasalis recurvus, the proportions of this part of the face are much diminished, and its form also modified. This species (which though doubted by some as being distinct, is, we be- lieve, truly so) takes an intermediate station between the Simia Nasalis, and the ordinary Semnopitheci with flat noses, thereby showing that the transition in this particular character is not abrupt; even were it so, an isolated point of this nature does not form a philosophical basis upon which to ground a generic distinction. So far I have alluded to external characters only ; it remains for me to give some account of the anatomical characters of this singular monkey, of which, as far as I can learn, modem naturalists do not appear to be aware. It would seem that M. Otto*, who described the sacculated form of the stomach in one of the monkeys of the genus Semnopithecus, is not the first observer of this peculiarity, for I find that Wurmb, in the Memoirs of the Society of Batavia, notices this point in the anatomy of an individual of the Simia Nasalis. After giving some interesting details respecting the habits and manners of the species, he proceeds as follows : — " The brain resembles that of man ; the lungs are of a snow-white colour ; the heart is covered with fat, and this is the only part in which fat is found. The stomach is extraor^ dinarily large, and of an irregular form ; and there is beneath the skin a sac which extends from the lower jaw to the clavicles.*' Aude- bert (with whose work * Histoire des Singes,' Geoflfroy St. Hilaire * See his paper in the " Nova Acta Academiae Caesareae," vol. xii. Phil. Mag. S. 3. Vol. 12. No. 78. Suppl. July 1838. 3 B 594 Zoological Society, was well ncquninted,) refers to this account of Wurmb ; yet Geoffroy does not, as far as I can find, advert to these points, unless indeed his statement of the presence of cheek-pouches be founded on the ob- servation of a sac extending from the lower jaw to the clavicles ; and if so, he has made a singular mistake, for the sac in question is laryngeal, and the words as they stand cannot be supposed to mean any thing else; I know of no monkey whose cheek-pouches extend be- neath the skin to the clavicles ; but the laryngeal sacs in the Orang and Gibbons, and also in the Semnopitheci themselves are remarkable for development. It is evident, however, from the silence of M. Geoffroy St. Hilaire respecting the laryngeal sacculus in the Proboscis Monkey that he was not aware of the real character of the structure to which Wurmb had alluded. With respect to the structure of the stomach, neither Wurmb nor M. Otto drew any general infer- ences from it ; they described it as it presented itself in single species, and regarded it in an isolated point of view ; it is, if I mistake not, to Mr. Owen that we owe its reception as an anatomical character, extant throughout the Semnopitheci. (See his paper on the subject, in the Proceedings for 1833* and in the Transactions of the Zoolo- gical Society, vol. i.) This is perhaps scarcely the place in which to introduce any spe- culations, but I cannot help observing that the same structure may be expected in the genus Colobus, which in form is a mere repetition of the genus Semnopithecus, except that the thumb of the forehands, which in the latter begins to assume a rudimentary character, is in the former reduced to its lowest stage of development. In both genera the teeth precisely agree, and present early that worn surface which is the consequence of a continued grinding rodent-like action, upon the leaves and herbaceous matter which constitute the chief diet of the animals. The statement of Wurmb respecting the stomach and laryngeal ap- paratus of the Proboscis Monkey I have lately been enabled to con- firm. Among the specimens in store brought within the last few months from the Gardens to the Museum occurred an example of the Pro- boscis Monkey, in brine, but in a state of decomposition which in- duced me to lose no time in making such an examination as its con- dition would admit, being indeed extremely anxious to ascertain the relationship of this curious monkey to the other groups of Indian Simiada, groups to which I have been lately directing my attention. The specimen in question was a female, measuring from the vertex to the ischiatic callosities one foot nine inches. The body was meagre and slender, and the limbs long and slim ; the contour of the animal being very unlike that displayed in the mounted specimen in the Museum of the Society, which gives the idea of great robustness. The abdominal cavity had at some former period been opened * [Noticed in Lend, and Edinb. Phil. Mag. vol. iii. p. 295.] Zoological Society, 595 and the liver removed, in doing which the stomach had been cut, but not so much as to spoil it entirely. In every essential point this viscus is the same as in all the Semnopitheci hitherto examined. It consists of a large cardiac pouch with a strong muscular band, running as it were around it so as to divide it into two compart- ments, an upper and lower, slightly corrugated into sacculi ; the caV' diac apex of the upper pouch projects as a distinct sacculus of an oval form, and is not bifid. From this upper pouch runs a long and gradually narrowing pyloric portion, corrugated into sacculi by means of three muscular bands, of which one is continued from the band dividing the cardiac pouch into two compartments. The elongated pyloric portion sweeps around the lower cardiac pouch. The oesophagus enters the first compartment about four inches from its terminal apex, giving oiF a radiation of longitudinal muscular fibres over the central portion of the first compartment. The second or lower compartment is the largest and deepest, and is embraced by longitudinal muscular fibres from the oesophagus to the division-band, but unlike the same compartment in the stomach of the Semnopithecus Entellus, it is very slightly sacculated ; indeed it can scarcely be said to be so at all. The admeasurements are as follow : feet, inches. 1st compartment, round the greater curve 1 6 2nd compartment, measured in the same manner 1 8J From the entrance of the oesophagus, round the 2nd compartment to the division-band 1 I The same measurement, round the 1st compart- ment 0 81 Length oi pyloric portion 2 1 Circumference at base 0 9J Circumference just above pyloric orifice 0 5| Length of small intestines 18 0 Length of large intestines 6 2 The average diameter of the small intestines, lying flat, was | of an inch ; the ileum, however, was rather more, but not quite an inch. The c(Ecum is of a pyramidal figure, 5 inches in length, pointed, and somewhat sacculated by three slight muscular bands. Circum- ference at the base, 5^ inches. The large intestines are puckered into sacculi by two longitudinal bands ; they commence large, becoming gradually smaller, the bands in the meantime gradually disappearing. Advancing towards the rectum the intestine again enlarges, and here, to the extent of 2^ feet from the anus, all trace of bands is lost. The circumference of the large intestines at their commencement is 31 inches. The lungs consisted of two lobes on each side, the fissure dividing the lobes on the right side being the most complete. The laryngeal sac was of enormous size, and single. It extended over the whole of the throat, and advanced below the clavicles, com- municating by means of a single but large opening with the larynx. This opening is on the left side, between the larynx and the os hy aides, 3B2 596 Zoological Society, and is capable of being closed by means of a muscle arising from the anterior apex of the os hyoides, and running down the central aspect of the trachea to the sternum. The contraction of this muscle draws the OS hyoides down, so as to press upon the edge of the thyroid cartilage. There were no cheek-pouches nor any traces of them. Tlie teeth were much worn, but the fifth tubercle of the last molar tooth of the lower jaw was very distinct. Mr. Gould afterwards called the attention of the Meeting to the common British Wagtail, and stated his firm conviction of its being distinct from the Motacilla alba of Linnaeus. He proposed for it the name of M, Yarrellii, and observed, that it might be easily distin- guished from the continental one, with which it had hitherto been confounded, by an attention to the following characters. The pied wagtail of England {M. Yarrellii) is somewhat more ro- bust in form, and in its full summer dress has the whole of the head, chest, and back of a full, deep, jet black ; while in M. alba, at the same period, the throat and head alone are of this colour, the back and the rest of the upper surface being of a light ash-grey. In winter the two species more nearly assimilate in their colouring ; and this circumstance has doubtless been the cause of their being hitherto considered identical ; the black back of M. Yarrellii being grey at this season, although never so light as in M. alba. An additional evidence of their being distinct (but which has doubtless contributed to the confusion), is, that the female of M. Yarrellii never has the back black, as in the male ; this part, even in summer, being dark grey ; in which respect it closely resembles the other species. July 25th, 1837. — Mr. Waterhouse directed the attention of the Meeting to several small Quadrupeds which he considered un- described. Phascogale flavipes, from North of Hunter's River, New South Wales. The fur of this animal is moderately long, not very soft, and con- sists of hairs of two lengths. On the back the shorter hairs are of a palish ochre colour at the apex, and the longer hairs are black : on the sides of the body and limbs the ochreous hue prevails, the black hairs being less numerous : the under parts of the body are of a yel- low colour, inclining to white on the throat and mesial line of the belly ; all the hairs are of a deep gray at the base both on the under and upper parts of the body. The general hue of the head is gray, a tint produced by the mixture of black and white hairs ; the eyelids are black : the hairs immediately above and below the eye are of a yellow- white colour, as are also those of the upper lip and lower part of the cheeks. The moustaches are moderately long ; the hairs are black at the base and grayish at the apex. The ears are of mo- derate size, and have the hinder portion emarginated ; they are fur- nished externally with minute hairs, those on the inner side being chiefly of a yellow colour. The feet are of an uniform deep ochre colour. The tail is about equal in length to the body and half the head, and is furnished with small and closely adpressed hairs, between Zoological Society, 597 which rings of scales are visible ; on the apical portion of the tail the hairs are longer, slightly exceeding one eighth of an inch in length ; the hairs on the under side of the tail are of a deep buff colour, and those of the upper side are black and yellow, excepting at the apex, where all the hairs are black. The teeth in this species agree in number with those of Phascogale penicillata, and in fact scarcely differ in any respect, making allow- ance for the diiFerence in the size of the animals. The two front in- cisors of both upper and lower jaws are perhaps smaller in propor- tion, and the third false molar in the lower jaw is decidedly smaller in proportion, being scarcely visible unless the gum be removed. The last molar of the upper jaw is of the same narrow form, and placed obliquely as in P. penicillata. Not having a skull oi P. penicillata, I am guided in my observations by M. Temminck's figure in the ' Monographies de Mammalogie.' * Upon comparing the skulls of P.flavipes with the same figure, the resemblance is great ; in the smaller animal, however, the skull is somewhat narrower in proportion (especially the fore part) ; the na- sal bones are not so broad at their base. Phascogale murina, from North of Hunter's River, New South Wales. This species may be readily distinguished from the former by its much smaller size, being in fact rather less than the common mouse {Mus musculus), or less than half the bulk of P.flavipes. The fur is rather short and soft ; its general hue is gray with a faint yellowish tint, the longer hairs on the upper parts of the body being gray at the apex, and the shorter hairs tipped with pale yellow or cream colour ; the feet and under parts are white, as are likewise the sides of the face beneath the eye. All the hairs of the body are of a deep slate colour at the base. The tail is covered with very minute closely adpressed silvery white hairs. The dentition is evidently that of an adult animal : the canines and anterior incisors of both upper and lower jaws appear to be smaller in proportion than in P.flavipes. Mus Hayi, from Morocco. This species, which is rather larger than Mus musculus, was pre- sented to the Zoological Society by E. W. A. Drummond Hay, Esq., Corr. Mem., after whom I have taken the liberty of naming it. Mus Alleni, from Fernando Po. This species is less than the harvest mouse {Mus messorius), and of a deeper colour than the common mouse {3Ius musculus), being in fact almost black. The ears are smaller in proportion, and more distinctly clothed with hairs. The tail is very sparingly furnished with minute hairs. The tarsi are covered with blackish hairs above; the toes are dirty white. I have named the species after Lieut. W. Allen, R.N., Corr. Mem. by whom it was discovered and presented to the Zoological Society. * In M. Temminck's figure the three lateral incisors of the upper jaw are represented as being close to the anterior pair. There is, however, a space between the anterior incisors and the lateral, both in P. 'penicillata and in the two species here described. 598 Zoological Society, Mus Abbottii, from Trebizond. This species is less than the harvest mouse (Mus messorius), and of a deeper colour than the Mus musculus, in which respects it agrees with Mus Alleni ; from this, however, it may be distinguished by the tail being longer in proportion, the ears larger, and the tarsi more slender. It was presented to the Zoological Society ,by Keith E. Abbott, Esq., Corr. Mem., after whom it has been named. Mr. Gould then continued the exhibition of Mr. Darwin's Birds, a series of which were upon the table. One only among them was considered new, a species belonging to the genus Pyrgita from the island of St. lago. Mr. Gould characterized it under the name of Pyrgita lagoensis, from St. lago. This is in every respect a typical Pyrgita, and rather smaller than the common species, P. domestica. Mr. Gould then called the attention of the Members to some spe- cimens of M. alba and M. Yarrellii, which presented in a very de- cided manner the distinctions referred to by him at the last Meeting, He afterwards characterized a new species of that genus under the name of Motacilla leucopsis, from India. August 8th, 1837.— Mr. Gould then characterised the following birds from the Society's collection as new species : Corvus nobilis, from Mexico. This beautiful species is a true raven, and may be distinguished from the European, and from that inhabiting the United States of America, by the more metallic lustre of its plumage, by its more lengthened and slender bill, the greater length of its primaries, and the more cuneate form of its tail. Ortyx guttata, from the Bay of Honduras ; Thamnophilus fuligi- nosus, from Demerara ; Dendrocitta rufigaster from India. Mr. Ogilby exhibited skinspf two species of his new genus Kemas*, and directed the attention of the Society to their generic and specific characters. Mr. Ogilby observed, that the genus in question occu- pied an intermediate station between the goats and the Oryges, agreeing with the former in its mountain habitat and general con- formation, and with the latter in the presence of a small naked muzzle and four teats in the females. Of the two species exhibited, one was a fine male specimen of the IJiaral, presented by James Far- rail, Esq., and the other a new species from the Neilgherry Hills, known to Madras and Bombay sportsmen by the name of the Jungle Sheep, and which Mr. Ogilby had long looked for. In form and habit of body, as well as in the character of the horns, this animal is intermediate to the Iharal and Ghoral ; the specific name of Kemas Hylocrius was proposed for it in allusion to its local appellation. The body is covered with uniform short hair, obscurely annulated like that of most species of deer, and more nearly resembling the coat of the Ghoral than that of either the Iharal or Chamois, the other species of which the genus is at present composed. The horns are uniformly bent back, surrounded by numerous small rings, rather flattened on the sides, with a small longitudinal ridge on the inner anterior edge : the ears are of moderate length, and the tail • [See Lond. and Edinb. Phil. Mag. vol. xi. p. 473.] Zoological Society. 599 very short. Mr. Ogilby entered at some length into the characters and relations of the genus Kemas ; he observed that naturalists and commentators had greatly puzzled themselves to discover the deri- vation of the word Kemas, and the animal to which the ancient Greeks applied that name. Among others, Col. H. Smith applies it to the Chiru, with which the ancients certainly were not acquainted : but Mr. Ogilby observed, that the root, both of the Greek Kemas and the modern Chamois, was manifestly traceable to the German word Gems, which is still the name of the Chamois eastward of the Rhine, and which the Dutch colonists have transferred to the Cape Oryx {Oryx capensis). August 22nd, 1837. — Mr. Owen brought before the notice of the Society, through the kindness of Mr. Edward Verreaux, the cranium of an Orang Outang (Simia Wurmbii, Fisch.), exhibiting an inter- mediate or transitional state of dentition, there being in the upper jaw the first or middle incisors, and first and second molares on each side belonging to the permanent series, and the lateral incisors, the canines, and the first and second molares (which are replaced by the bicuspides) belonging to the deciduous series ; and in the lower jaw, both the middle and lateral incisors, and first and second molares on each side belonging to the permanent series, and the second left lateral deciduous incisor (not yet shed), the deciduous canines, and the first and second deciduous molares. The permanent teeth, which were in place, corresponded in size with those of the great Pongo of Wurmb, and prove that the Orang differs from man in the order of succession of the permanent teeth, having the second true molar, (or fourth if the bicuspides are reckoned as molars), in place before the appearance of the permanent canines. Mr. Owen remarked, that the intermaxillary suture still remained unobliterated in the immature cranium exhibited, and he conceived that the ultimate obliteration might be caused by the increased vas- cularity of the parts during the protrusion of the great laniary teeth. In the Chimpanzee this obliteration takes place at a much earlier period. Although the marks of immaturity, and consequently those which impress an anthropoid character upon the skull of the Orang, were generally present in the head exhibited, yet, on a comparison of it with the skull of a younger Orang in which all the deciduous teeth were retained, an approach to the condition of the mature cranium might be observed in the greater protrusion of the intermaxillaries, the lengthening of the maxillary bones, a thickening and greater prominence of the external and superior boundary of the orbit, an enlargement and thickening of the malar bone and zygoma, in the commencement of the development of the cranial ridges, and in the widening and deepening of the lower jaw*. Mr. Owen then directed the attention of the Meeting to an ex- * [Abstracts of Prof. Owen's former memoirs on different species of Orangs have appeared in Phil. Mag. and Annals, N.S. vol. ix. p. 60 ; and Lend, and Edinb. Phil. Mag. vol. vi. p. 457, and vol. x. p. 295.— Edit.] 600 Zoological Society. ceedingly interesting preparation of a foetal Kangaroo, with its ac- companying uterine membranes, upon which he proceeded to offer some observations. He remarked, that in a paper read before the Royal Society in 1834*, he described the foetus and membranes of a Kangaroo {Macropus major), at about the middle period of uterine gestation, which in that animal lasts thirty -eight days. In this in- stance the condition of the membranes, and the relation of the foetus to the mother, were essentially such as are found to exist throughout the ovo-viviparous reptiles, with the exception of there being no trace of the existence of an allantois. Mr. Owen, in order to determine whether an allantois was developed at a subsequent period of the growth of the embryo, dissected very young mammary foetuses of different marsupial animals, as the Kangaroo, Phalangista, and Fc- taurus ; and finding in them the remains of a urachus and umbilical vessels, he stated that " it would appear that an allantois and um- bilical vessels are developed at a later period of gestation, but pro- bably not to a greater extent than to serve as a receptacle of urine.'* (Phii. Trans., 1834, p. 342.) The examination of a uterine foetus of a Kangaroo kindly placed at Mr. Owen's disposal by Dr. Shearman, and exhibited on this occasion to the Society, has proved the accuracy of this prevision. The chorion, which enveloped and concealed the foetus, was a sac of considerable capacity,exceeding probably by ten times the bulk of the foetus and its immediate appendages, and adapted to the smaller cavity of the uterus by being disposed in innumerable folds and wrinkles. It did not adhere at any part of its circumference to the uterus, but pre- sented a most interesting modification not observed in the previous dissection of the Kangaroo's impregnated uterus, viz., that it was in part organized by the extension of the omphalo -mesenteric vessels upon it from the adherent umbilical sac. The foetus was further ad- vanced than the one previously described in the Philosophical Trans- actions. The digits on the hinder extremities were distinctly formed. The umbilical chord extended nearly three lines from the abdo- minal surface of the foetus ; the amnios was reflected from this point, to form the usual immediately investing tunic of the foetus ; and, beyond the point of reflection, the chord divided into a very large superior vascular sac, organized by the omphalo-mesenteric vessels, corresponding in all respects with the vitelline sac described and figured in Mr. Owen's first paper ; but below the neck of this sac there extended a second pyriform sac, about one- sixth the size of the vitelline sac, having numerous ramifications of the umbilical vessels, and constituting a true allantois. This sac was susi^ended freely from the end of the umbilical chord : it had no connexion, at any part of its circumference, with the chorion, and consequently was equally free from attachment to the parietes of the uterus in which the foetus was developed f. ♦ [See Lend, and Edinb. Phil. Mag., vol. iv. p. 438.] + 'J'hc following note has been communicated by Mr. Owen to be ap- pended as a postscript to the above remarks. " Ilavhig been anticipated Meteo7vlogical Society, 601 Mr. Charlesworth then exhibited a series of specimens of the paper nautilus, in several of which injuries to a very considerable extent had been repaired with new substance agreeing in every respect with the original shell ; affording the most decisive evidence that the animal by which they were constructed possessed the same re- l)arative powers as other testaceous molluscs. It would appear from the observations of Captain Rang, who had recently repeated at Algiers the experiments originally undertaken by Madame Jeanette Power at Messina, that the Poulp does not fill up the breaches arti- ficially produced in its habitation by a deposit of shelly matter, but with a transparent diaphragm, which has neither the texture, white- ness, or solidity of the original shell. This fact, in connection with the specimens exhibited to the Meeting, apj^eared to Mr. Charles- worth strongly to confirm the opinion entertained by Mr. Gray, De Blainville, and others, of the parasitic character of the genus Ocythoe. Mr. Owen remarked, that he could not admit the validity of the line of argument adopted by Mr. Charlesworth, because the dif- ferences in the nature of the rejiroduced portions might depend upon the particular part of the shell in which the perforation or fracture had been effected, and a consequent difference in the repro- ductive powers of the corresponding part of the mantle. METEOROLOGICAL SOCIETY. April 10, 1838. — An interesting paper on the cold of January last, as experienced at Brussels, communicated by Prof. Quetelet, Secretary to the Royal Academy of Brussels, was read by the Secretary. The extreme cold which occurred on the 20th of the in the description of my preparation, so far as relates to the allantois, by M. Costc, I here subjoin, by permission of the Committee of Publi- cation, a statement of the circumstances which enabled that embryologist to announce the discovery of the allantois to the Academy of Sciences. In a recent work on Embryogeny, M. Coste * has stated that the Marsupiata differ from other Mammaha in the absence of an allantois, — a statement which appears to have arisen from a misconception of my memoir in the Philosophical Transactions for 1834, in wliich, although the allantois was not developed in the embryo, whose dissection is there figured, (PI. VII. fig. 1.), yet the evidences of the ulterior development of an allantois in dif- ferent marsupial genera, are described in the text, (p. 338, 312.) I therefore took the opportunity of showing to Dr. Coste during his visit to England the foetal Kangaroo with the allantois now before the Society; and Mr. Coste having expressed some doubts respecting my determination of the two ap- pended sacs, we together dissected the fa^tus, and found that the vessels ra- mifying on the larger sac, which 1 had before described as the umbilical vesicle, had the usual disposition and connections within the abdomen of omphalo-mesenteric trunks, corresponding with the figure above-cited in the Philosophical Transactions, and that the allantois was continued from an urachus, such as is represented in figs. 6, 7 and 8, pi. VII., Philos. Trans., 1834." * Emhryogenie comparee, p. 118. 602 Notices respecting Ne'w Books. month was 5" Fahr. This was the coldest January since 1823, the lowest point of which was stated by M. Quetelet to be 11° Fahr. M. Crahay noticed the thermometer at Maestricht on the same day to stand at 9^ degrees below zero. A short jiaper was next read from Prof. Wartmann, Geneva, giving an account of an atmospheric bow, which was seen on the 12th February 1837, in jierfectly serene weather; it exhibited all the colours of the rainbow in a very distinct manner, but it did not appear in a vertical position like the ordinary rainbow, but inclined to the plane of the earth ; it did not partake in any degree of the nature of a halo. It became visible at 5 minutes past 10 a.m., the sun shining with all its brightness, and lasted till 45 minutes past 10 a.m. It was not accompanied by any i)arhelia, nor was there any appearance of cloud till half past 11 a.m., when a few light clouds were seen passing in the superior strata of the atmosphere ; the afternoon was overcast without rain. LXXXV. Notices respecting New Books. Analytical Geometry : Part First, containing the Theory of the Conic Sections ; Part Second, the Theory of Curves and Surfaces of the Second Order. By J. R. Young, Professor of Mathematics, Royal College, Belfast. 2 vols. 12mo. Souter. 1'^HE properties of curves and surfaces of the second order, whilst - they are the most interesting of all geometrical speculations, are at the same time the most important in their application to physical inquiry. They did not, however, originate in the wants of the phy- sical inquirer ; nor, indeed, have any great number of them been discovered since the time of Kepler. There are comparatively few properties of these curves now known to geometers, which were not either known to the ancients, or which are not merely easy deduc- tions from such as were known to them. If we except the doctrine of curvature, and the properties derivable from Desargue's theorem upon the " involution of six points," it would be difficult to specify a proposition which is not included under the statement just made. At all events, if a different view should be taken of it, no one will contend that the discovery of these properties, with very rare ex- ceptions, was the consequence of any feeling of a want of them for aiding philosophical inquiries. In truth, almost numberless as the properties of the conic sections are, the number which the physical inquirer needs is very few ; and for the most part, these are comparatively elementary and easy of demonstration, either after the manner of the ancients or by the geometry of coordinates. The greater portion of them in the present state of science are mere objects of enlightened curiosity and analy- tical or geometrical exercise. Were we, however, to make the wants of natural philosophy the standard of utilit}% we should greatly mistake the objects of mental culture, and in no case more completely than in the one before us. Professor Young's Analytical Geometry, 603 We might at once urge that by the same rule practical utility would become the standard by which we should measure the extent to which natural philosophy itself ought to be pursued. Of the two methods by which the properties of the conic sections and surfaces of the second order may be demonstrated, (the method of coordinates and the methods of pure geometry,) the prevailing prejudice is in favour of the former. That the coordinate method harmonizes much better with the general methods of inquiry which are found most advantageous in physical research, no one can deny ; but in any other point of view the superiority of this method is very doubtful. As an intellectual exercise there can be no question re- specting the superiority of the ancient methods : as an instrument of investigation of the properties of curves and surfaces of the second order, the method of transversals (especially when we adopt Chasles's application of Prop. 129. lib. vii. of the Mathematical Collections of Pappus,) is by far the most ready and effective, as well as the most general and comprehensive. On the other hand, if the investiga- tion of these properties be viewed in reference to exercising the student in the modes of investigation that he will be most frequently required to employ in physical research, the geometry of coordinates should be the sole method he should employ. Every judicious stu- dent will, however, acquaint himself in some degree with the other methods, — fashionable as it is in our day and in this country, (but in this country only,) to treat such modes of research as antiquated and unworthy of notice. The systematic introduction of surfaces of the second order into an elementary course of study is comparatively recent ; for, though surfaces of revolution were considered by the Greeks, only very few of their properties had been investigated prior to the time of Monge, Hachette, and their disciples of the Polytechnic School. So assi- duously, however, have these surfaces been studied since, that their known properties in their most general form are as numerous, (or perhaps more numerous) as even those which relate to lines of the same order ; and no treatise on analytical geometry can be considered complete without the introduction of a considerable number of these. Nor are they mere subjects of speculative curiosity even in themselves. They have a direct bearing on several physical subjects of inquiry. Their great utility, however, arises from the exercise they alFord to the student in the discussion of phaenomena taking place in space of three dimensions — that is, in short, of nearly all the phaenomena of inorganic nature. Very few motions take place in one fixed plane, and even these can be studied only in reference to some other plane or planes. They are always, or almost always, in curves of double cur- vature, or upon curve surfaces ; and when not so, the lines or planes in which they take place cannot be contemplated and determined but by means of some other lines and planes in which the component forces act. To speak familiarly, they are resultants to be deter- mined— not composants actually given. The attachment to the coordinate method of geometrical research in reference to its ulterior physical application, is not a mere preju- 604< Notices respecting New Books. dice in the ordinary sense of the term ; though it must be admitted, on the contrary, to have engendered a prejudice against the other methods which only a very partial view of the intellectual objects of mathematical science could have rendered so generally current. It would, however, be impossible in our limited space to enter upon this discussion at any length ; and we merely throw out these sug- gestions for the consideration of those who have adopted a prejudice against methods, solely because they are in favour of a system of investigation w^hicli more immediately and advantageously applies to that branch of study to which they have devoted their attention. These persons may be reminded that even philosophy in comparison with the arts of life is secondary, on precisely the same ground that pure mathematics, in their own creed, is secondary to physics : and then we are brought back by an application of their own ar- gument to the superiority of the Greek over the coordinate geo- metry. In all the arts of life constructive processes are required, — not Eilgebraical expressions of value ; we have to actually draw the line, and cut the body into a certain form and of certain dimensions, — not to compute the coordinates of points, or to form the equations of lines and surfaces. We must supply methods of actually tracing the contours of the bodies to be formed, and that by practicable processes, rather than give the relations of the coordinates of the curve or surface. Who would think of assigning the equations of the lines which by their intersection give the vanishing points of any line in a picture ? Who would ever dream of laying down every point of a building from an algebraical formula } What architect would commence his operations for a roof, an arch, a groin, an ogee, by finding their equations ? What carpenter would calculate the points of a handrail of a circular staircase from its equation .? What mason would adopt such a method for cutting the complicated stones that are required in an ornamental building .f* Plain, straightfor- ward, and simple geometrical constructions are those required in all the arts, both of life and refinement. But it is time that we briefly notice the two elegant volumes before us. A considerable number of works of this class have been published on the Continent, though this country can boast but very few ; and of those few, it does not appear that any one of them supersedes the necessity of that now under consideration. For the greater part they are mere compilations ; in most cases professedly so. Mere compilation never yet produced a good book on science. To effect this, something more is required than a mere translation of detached passages from other writers. That author who succeeds in pro- ducing a good elementary work on any scientific subject must possess powers of a high order, and knowledge very extensive, an original cast of thought, and a clear comprehension of the philosophy of science. We think ourselves tolerably familiar with the foreign writers on these subjects, and we know of no work that, for the pur- poses of useful and careful study, could be so advantageously put into the hands of the novice as that of Professor Young. The continual Intelligence and Miscellaneous Articles, 605 cautions against too hasty inferences from the algebraical results, (the great scientific vice to which the method itself is calculated to give birth,) the reiterated suggestions respecting the kind of caution to be observed in interpretation, and the repeated explications of the singular and seemingly absurd expressions that result from the investi- gation,— these, more than in any work we are acquainted with, render it a valuable book of early study. The unity of the system of develop- ment too, — the logical concatenation of the several parts, — the gene- rality and completeness of the methods ; — these give it a character pe- culiar to itself amongst English works on the subject, and a peculiarity which every judicious teacher knows how to estimate properly. We remark, too, much that may be called original in method ; more, indeed, than in an elementary book we should reasonably look for. To one point only can we advert here. The doctrine of curvature has always been the great obstacle to the production of a treatise on the conic sections, which should not either directly or implicitly involve the employment of the principles of the differential calculus. This difficulty is at length overcome by Professor Young, and the entire investigation is rendered one of purely elementary algebra. It would have given us pleasure to be able to transfer it to our pages ; but as the work is accessible to our readers, we think it unnecessary to do so. LXXXVI. Intelligence afid Miscellaneous Articles, TARTARIC AND PARATARTARIC ACIDS, ETC. M DUMAS has read before the Royal Academy of Sciences of • Paris, a report in his own name and those of MM. Robiquet and Pelouze, on a memoir of M. Fremy, relating to the modifications which heat occasions in tartaric and paratartaric acids. It was first remarked by M. Braconnot, that tartaric acid when submitted to fusion was changed in its properties. M. Fremy has investigated this subject, and stated the results in the memoir now reported. The reporter observes, that the nature of the oxygenated acids may be explained by two theories, both of which are probably true, but which are probably only applicable to a certain number of bodies. One of these theories, and that which is almost universally admitted, consists in regarding them as distinct bodies, as true oxygenated acids, which combine with water and bases to form salts. The other theory does not regard these as acids when they are an- hydrous, but considers them as hydro-acids, and their salts as ana- logous to the chlorides. These two theories are most opposed to each other in relation to the nature of tartaric acid ; for one of them, that which considers tar- taric acid as an oxacid, is incompatible with the analysis of anhydrous emetic tartar ; and if, according to the composition of this sub- stance, tartaric acid is considered as an hydracid, a difficulty im- mediately occurs in accounting for the results obtained by M. Fr^my ; these are indeed much more easy of explanation in considering tar- taric acid as an oxacid, as will appear on examination. 606 Intellifience and Miscellaneous Articles, 'to M. Fr^my has discovered the substance which, according to the views generally admitted, ought to have the name of anhydrous tartaric acid. He obtains it with great facility, for it is sufficient to expose tartaric acid to the action of heat in a capsule. The acid fuses, loses water, swells up, and leaves a spongy mass which con- sists mostly of anhydrous tartaric acid ; it is so sparingly soluble in water, that this fluid dissolves from it the tartaric acid, which has not been completely deprived of water. It is well known that the composition of racemic or paratartaric acid is similar to that of tartaric acid. In all destructive re- actions, tartaric and racemic acids undergo similar alterations, so that up to the present time nothing is known which explains the differences that may exist in their rational formulae. M. Fremy sub- jected paratartaric acid to the same treatment as that by which he obtained anhydrous tartaric acid, hoping that some difference would appear in this way between these two bodies ; none how- ever occuiTcd. Paratartaric acid behaved like tartaric acid, and yielded an analogous substance, which must be considered as an- hydrous paratartaric acid. Connected with these facts, which are sufficiently remarkable on account of the two acids obtained, M. Frdmy communicated two others, which on account of their novelty, have strongly excited the attention of those who are engaged in the development of or- ganic chemistry. In fact it is not anhydrous tartaric acid which is directly produced by the fusion of tartaric acid. Before it arrives at this condition, common tartaric acid gives rise to two intermediate products, of great interest as regards theory. The first is tartralic acid, the se- cond the tartrelic acid of M. Fremy. The tartralic acid is repre- sented by tartaric acid, which, instead of saturating two atoms of base, saturates only | atoms. Tartrelic acid is represented by tartaric acid, which saturates only one atom of base. So that com- mencing with the most probable formula for tartaric acid* C"^ H^ 01°, 2H'^ O, or C'^' H'2 0'2, it will be seen that the three products in question will be represented as follows, in their respective salts of lead. C'6H« 0'«, 2PbO tartrate. C16 H8 O'o, |PbO tartralate. CiG H8 O'", PbO tartralate. M. Fr^my has thus ascertained, that in proportion as tartaric acid loses water, it gives rise to bodies which combine with smaller quantities of base, and which form salts with bases equivalent to the proportions of water which they retain. These modifications recall those which have been assigned by Professor Graham as the causes of the variations which phosphoric acid and the phosphates undergo by the action of heat. The author has satisfied himself that the tar- tralic and tartrelic acids readily return to the state of tartaric acid. The reporter observes that it results from the experiments of * These are the formulae in the original. Intelligence a7id Miscellaneous Articles, 607 M. Frcmy, that tartaric acid may lose water and go through modifi- cations analogous to those of phosphoric acid, until it becomes an- hydrous tartaric acid. Paratartaric acid undergoes the same changes. M. Fremy has therefore introduced into the study of the organic acids a new point of view, and which is exclusively his own. He seems, at first, to have decided the question concerning their nature, since by discovering anhydrous tartaric acid he appears to have re- moved all doubt as to the formula of this acid in the state of hy- drate. But with a little attention it will be observed that these new results are easily explained when tartaric acid is considered as a hydracid. In fact, in such proportion as tartaric acid loses water, it gives rise to products whose capacity of saturation diminishes until it entirely ceases. For anhydrous tartaric acid is no longer to be considered as an acid, and after tartrelic acid, other substances are formed which have still less saturating power. Tartaric acid and the new acids described by M. Frcmy may be regarded as distinct hydracids. As to anhydrous tartaric acid, this would be a product of decomposition, but not itself an acid. These theoretic views it was considered necessary to detail in order to prove that the researches of M. Fr^my do not in any way destroy the results given by the analysis of emetic tartar. — L'Institut, May 3, 183S. ON THE ACTION OF FERMENTATION ON A MIXTURE OF OXYGEN AND HYDROGEN GASES. BY M. THEOD. DE SAUSSURE. It is well known that the quantity of hydrogen gas contained in the atmosphere does not amount to 1-lOOOdth of its volume. Nevertheless the decomposition of organic matters continually adds fresh quantities of this gas to atmospheric air ; on the other hand there are few substances which occasion the combination of hydrogen with oxygen at common temperatures; and the circumstances which the combination requires, prove that the disappearance of the hydro- gen cannot be accounted for in this way. M. de Saussure states that he has found that the combination is effected by the fermentation of organic substances universally distributed over the surface of the soil, even when on account of the smallness of their quantity and the slowness of their operation no rise of temperature takes place. By exposing fermentable bodies in pieces of the size of a nut to the mixed gases M. de Saussure has arrived at the following con- clusions : — The combination of hydrogen and oxygen gases may be effected without inflammation at the temperature of the air, by bodies submitted to slow fermentation. They usually produce this combination when they are accumu- lated and impregnated with a sufficient quantity of water to pre- vent their complete contact with the oxygen gas. If this contact be made by increasing the surface of the fermentable body, or by diminishing the quantity of water, the hydrogen gas is not absorbed, and the oxygen gas disappears in other combinations. The porosity of the fermenting body greatly contributes to the destruction of the detonating mixture. Many observations prove that the hydrogen gas which disappears 608 Intelligence and Miscellaneous Articles. by fermentation combines with the oxygen gas, in the proportion ot the elements of water. The demonstration requires that the oxy- gen shall be employed only to form this water, and all the carbonic acid produced in the operation. The fermentable substances mentioned in the memoir do not effect the combination of the oxygen and hydrogen gases before they ferment, nor when the fermentation is stopped by an antiseptic. Soils and humus, mixed with different earths, undergo a slow fer- mentation as soon as they are moistened, which gives them the power of destroying the mixture of oxygen and hydrogen gases. Gaseous oxide of carbon, carburetted hydrogen gases, hydrogen gas obtained by decomposing water with red hot iron, were not de- stroyed by fermentation when they were substituted for common hydrogen gas, in the explosive mixture formed of two volumes of hydrogen gas and one volume of oxygen gas. Azotic, hydrogen and oxygen gases, added to the explosive mixture, do not present any remarkable obstacle to the destruction of an explosive mixture by a fermenting body, nor to that which is effected under the same cir- cumstances by a plate of platina recently cleaned. Oxide of carbon and oleliant gas and others, which prevent the combination of oxygen and hydrogen by platina, are also great obstacles to the same result by fermentation. Nitrous oxide, added to the explosive mixture, was partly decom- posed by fermentation, and did not prevent the combination of the hydrogen and oxygen gases. — Bihl. Univ, Feb. 1838. ACTION OF SULPHATE OF AMMONIA UPON GLASS. A mixture of muriate and nitrate of ammonia strongly corrodes glass, particularly glass containing lead. Sulphate of ammonia has precisely a similar action. As this salt upon being heated parts ■vsdth a portion of its base, it may be considered as a salt with excess of acid. When heated in a glass vessel to the temperature of 316° Fahrenheit, it begins to melt : up to 600'' Fahrenheit it does not suffer any further changes ; at this temperature ammonia is driven off, sulphate and sulphite of ammonia sublime and the glass vessel is much corroded. The whole inner surface of the glass becomes dim, while the sulphuric acid combines with the potash, and probably the ammonia as it is driven off combines with the silicic acid. The glass generally flies to pieces and in the centre is much acted upon ; the fragments are fused with difficulty, and are recognised by the blowpipe as sulphate of potash. I have often further remarked that the watch-glasses (containing lead) which I am in the habit of using, to dry substances in vacuo over sulphuric acid, after from two to four weeks become covered with numerous flaws, and small splinters may be easily separated from them. I have not been able to detect any loss of weight, there- fore the appearance cannot be due to the abstraction of any air con- tained in the glass, as Bischof, who observed something similar, sur- mises. I have never observed the same action to take place upon the glass of the air-pump or upon other glass. R. F.Manhand. — Poggendorff's Annalen, 1837, No. 12. INDEX TO VOL. XII. ilBBOTT (!l.) on the variation of a triple integral, 363. Abel, exposition of his argument respect- ing equations of the fifth degree, 1 16. Absorption of light, on Von Wrede's the- ory of, 114. Acids: — camphoric, 297; citric, 381 ; hy- pophosphomcsitylous, 101; lactic, 142; new, 220 -, retinic, 560; tartaric, 381; paratartaric, 605, JEther, sulphurous, on, 474. Agnew on the pyramids of Gizeh, 379. -S^therine, sulphate of, 474. iEthers, action of chlorine on, 297. Afzelius (Dr.), notice of the late, 279. Air, atmospheric, on the quantity of oxygen in, 401. Airy (Prof.) on the parallax of a Lyrae, 280; on the intensity of light in the neighbourhood of a caustic, 452. Alcohol, a new acid formed by its combus- tion around an incandescent platina wire, 220. Alkaline nitrates and earthy carbonates, analogy in atomic constitution between, 480. Alum, a new variety of, 103, 124; chrome alum, new method of obtaining, 218. America, South, geology of, 516. Ammonia, sulphate of, its action on glass, 608. Analysis, on the employment of metallic sulphurets in, 137; chemical, 229; of some double salts of mercury, 235. Analysing organic compounds, method of, 31, 232. Andrews (Dr.) on the action of nitric acid upon bismuth, &c., 305. Anthon (M.) on the employment of metal- lic sulphurets in analysis, 137. Apjohn (Prof.), examination of eblanine, 98 ; on the specific heats of the aeriform fluids, 101 ; on a new variety of alum, 103, 124. Arragonite, on the formation of, 465. Arsenical copper, 217. Astronomy, determination of the constant of lunar nutation, 110; on the parallax of a Lyrae, 280 ; on a very ancient solar eclipse observed in China, 282 ; on the repetition of the Cavendish experiment for determining tlie mean density of the earth, 283 ; remarkable increase of mag- nitude of the star /j, 521, 526 ; value of Third Se7'ies. Vol. 12. 3 the mass of Uranus, 522 ; longitude of the Edinburgh observatory, 525. Atmosphere, constitution of the, 158, 397. Atomic constitution, supposed analogy in, between the earthy carbonates and alka- line nitrates, 481. Australia, on the quadrupeds of, 95 ; pro- jectile weapon of the Australians, 329. Aurora boreal is, Feb. 18, 98 ; at Bermuda, 42. Austen (R. A. C.) on the geology of De- vonshire, 564. Azote, sulphuret of, 134. B. D. on the path of the boomarang, 329. Babington (C. C.) on the structure of Cus- cuta europaea, 531. Baily (F.), description of the Royal Soci- ety's new barometer, 204 ; on the repe- tition of the Cavendish experiment for determining the mean density of the earth, 283. Bark, its structure and growth, 54. Barometer, new, belonging to the Royal Society, 204. Batten (Dr.), notice of the late, 277. Becquerel (M.), the Copley medal awarded to, 348. Bell (Dr.) geology of Mazunderan, 571. Bell (T.) on the genus Galictus, 529. Bennett (G.) on the phosphorescence of the ocean, 21 1. Bentham (G.) on the Mora tree of British Guiana, 532. Benzin, production of, 460. Benzoic acid, action of iron at a high tem- perature on, 460. Berzelius (M.) on xanthophylle, 135. Bibliographical Bulletin, 208. Bichromate of the perchloride of chrome, 83. Birch, structure and growth of the bark of the, 55. Bird (G.) on induced electric currents, with a description of a magnetic contact- breaker, 18; on indirect chemical ana- lysis, 229. Bismuth, on the peculiar voltaic condition of, 48 ; action of nitric acid upon, 305. Blake (J.) on the electrical currents pro- duced during the processes of fermenta- tion and vegetation, 539. Blood, on the gases contained in the, 300. Bonaparte (C. L.) on the arrangement of the vertebrate animals, 92. 610 INDEX, Books, new, 127, 202, 263, 379, 536, 602. Boomarang, on the path of the, 329. Booth (J.) on the conic sections, 104. Botany : — on the structure and growth of the more perfect plants, 53 ; on the stem of plants, 62 ; Cucubalus baccifer found in the Isle of Dogs, 93 ; fossil ferns, 95; Laminaria digitals, 96 ; on the genus Chara, 97; development of the organi- zation in phaenogaraous plants, 172, 241, 292 ; Flora of Jamaica, 263 ; structure of Cuscuta europa?a, 531 ; on the mosses of Upper Assam, 532 ; Mora tree of Gui- ana, 532 ; existence of stomata in moss- es, 533. Bottinger (M.) on the colours of metals, 298. Brayley (E. W.) on the theory of volcanos, 533; on the porphyritic amygdaloid of Devonshire, 568, note. Brett (R. H.) analysis of some double salts of mercury, 235. Brewster (Sir D.) on a singular develop- ment ofpolarization in the crystalline lens after death, and on cataract, 22 ; on Von Wrede's theory of the absorption of light, 115 ; on Poisson's theory of the atmo- sphere, &c. 1 23 ; on the colours of mixed plates, 355. British Association for the Advancement of Science, 110. Brooke (H. J.) on an apparent case of iso- morphous substitution, 406. Broughton (J. D.), notice of, 278. Burr (F.), geology of the line of the Bir- mingham and Gloucester railway, 573. Butler's (Dr.) theory of the action of the siphnncle in the pearly nautilus, 503. Bunt (T. G.) on a new tide-gauge, 430. Cabiric mysteries in India, 110. Calc spar, on the formation of, 465. Calculi, composed of cystic oxide, 337; uri- nary, account of the collection in St. Bar- tholomew's Hospital, 412. Cambridge Philosophical Society, 452. Camphor, action of iron at a high tempera- ture on, 460. Camphoric acid, 297. Carbonate of lime, crystalline form of, 465, 470. Carbonates, earthy, and alkaline nitrates, analogy in atomic constitution between, 480. Carmine, adulteration of, 462. Cataract, on, 25. Cetrarin, on, 296. Chara, influence of heat, &c. on the circu- lation of the, 457. Chelostoma florisomnis, 18. Chemical analysis, indirect, 229. Chloride of tungsten, on, 461. Chlorides, metallic, their detection in bro- mides and iodides, 136. Chlorine, new compounds of, 220 ; its ac- tion on a;theis, 297. Chloro-cyanide of ammonium andmercury, analysis of, 256; of sodium and mer- cury, analysis of, 237 ; of calcium and mercury, 238 ; of barium and mercury, analysis of, 239; of magnesium and mer- cury, analysis of, 239 ; of strontium and mercury, analysis of, 240. Chromate of lead, dimorphism of, 387. Chrome aUm, new method of obtaining, 218. Chrome, bichromate of the perchloride of, 83. Chromium, teriodide of, 321. Citric acid, constitution of, 381. Clark's (Mr.) geological survey of Suffolk, 512. Clarke ( Rev. W. B. ) on the peat bogs and submarine forests of Bourne Mouth Val- ley, 579. Coal deposits of England, on the unity of the, 127. Colebrooke (H. T.), notice of the late, 272, 438. Colombia, meteorological observations made between 1820 and 1830, 148. Colouring matter of leaves in autumn, 135. Colours of metals, 298 ; of mixed plates, 355 ; of thin plates, mode of exhibiting, 28. Conic sections, on the, 104. Conilurus, a new species of the Australian Rodent, 96. Cooper (D.) on the luminosity of the hu- man subject after death, 420. Copper, arsenical, 217; protoxide of, the action of protoxide of iron on, 299. Cork, on the formation of, 54. Crabro spinipectus, 15. Cratoraus megacephalus, 14. Crook (Dr. W. H.) on the unity of the coal deposits of England, 127. Crystalline form of carbonate of lime, 465, 470. Crystalline lens, on a singular development ofpolarization in the, 22. Crystalline structure, on, 145. Crystals : — of the hydrates of barytes and strontia, 52 ; on the optical theory of cry- stals, 73, 259, 341. Cucubalus baccifer, 93. Curtis's (J.) Guide to an Arrangement of British Insects, 202. Cuscuta europsa, structure of, 531. Cyanogen, on, 339. Cystic oxide, on calculi composed of, 337. Dalton (Dr.) on the constitution of the atmosphere, and on the sulphurets of lime, 158, 397. Daniell ( Prof. ), the Copley medal awarded to, 350 ; on voltaic combinations, 364. Darwin (Mr.) on the formation of mould, INDEX. 611 89 ; on the geology of South America, 516; on the connection of certain vol- canic phenomena, 584. Davidson (J. ), notice of, 279. Deaseand Simpson's discovery of the North- west passage, 542. De la Rive ( Prof. ) on an optical phenome- non observed at Mont Blanc, 1 22 ; on the interference of electro-magnetic currents, 122. De Morgan (Prof.) on the relation between the number effaces, edges, and corners in a solid polyhedron, 323. Density of liquids, on the, 1. Despretz (M.) on the maximum density of liquids, 1. Devonshire, geology of, 510, 564. Didelphis hortensis, a new species of opos- sum, 215. Dimorphism of the chromate of lead, 387. Diodontus insignis, D. gracilis, and D. cor- niger, habits of, 16. Diplodus gibbosus, 86. Dipus Mitchellii, a new species of the Au- stralian Rodent, 96. Dublin, account of the magnetical obser- vatory at, 119. Dumas (M.) on the constitution of some organic acids, 381 ; on tartaric and para- tartaric acids, 605. Dumasine, on, 108. Dynamics, geological, 517. Earth, on the Cavendish experiment for de- termining the mean density of, 283. Earth-worm, vegetable mould produced by the digestive process of, 89, 518. Earthquakes, theory of the cause of, 584. Eblanine, examination of, 98. Edinburgh Observatory, longitude of, 525. Ehrenberg (M.) on the adulteration of car- mine, 462. Electricity: — chemical composition of the electrical apparatus of the torpedo, 256; current electricity, 18, 293, 311, 539; Prof. Faraday's researches in, 206, 358, 426, 430; electrodynamic induction, 18; electro-magnetic currents, interferenceof, 122; magnetic contact-breaker, 18; elec- tro-magnetic motive machines, on, 190; researches relative to the torpedo, 1 96 ; peculiar voltaic conditions of iron and bismuth, 48 ; voltaic, 225 ; voltaic com- bination, 364 ; on the primary forces of, 486. Elliptical polarization, cause of, iO. Emmett (Lieut.-Col. ;, meteorological ob- servations made at li\irmuda in 1836-37, and notice of an aurora borealis seen in low latitudes, 42. Entomology : — economy of several species of hymenoptera, 14; on the family of Fulgorida;, 93; Curtis's Guide to an Arrangement of British Insects, 202; 3 several new species of insects of the fa- mily of sacred beetles, 441 ; equations of the fifth degree, on Abel's argument, 116. Equilibrium of fluids, on, 385. Equivalents of potash, soda, and silver, on, 324. Eye, on the polarizing structure in the cry- stalline lens after death, 22; on cataract, 25. Falconer ( Dr. ) on additional fossil species of quadrumana from the Sewalik Hills, 34. Faraday (Prof.) researches in electricity, 206, 358, 426, 430 ; corrected report of his eleventh series of experimental re- searches in electricity, 538. Farish (Prof.) notice of the late, 437. Feathers, process for taking impressions from, 451. Felis Darwinii, on the, 213. Fellenberg (M.), method of dissolving iri- dium, 141. Fermentation of sugar of milk, 139; action of fermentation on a mixture of oxygen and hydrogen gases, 607. Fish, fossil, 86. Fluids, aeriform, specific heats of, 101. F'luorine, on, 105. Fogs, low, and stationary clouds, 355. Forbes (Prof.) on the meteors of Nov. 12, 85 ; researches on heat, 545. Fossil ferns, 95 ; fishes in the Lancashire coal-field, 86 ; quadrumana, 34. Fresnel's optical theory of crystals, 73, 259, 341 ; wave-surface, method of finding the equation to, 335. Frog, on the contractions of the, 1 97. Fulgoridae, on the family of, 93. Galictis, on the genus, 529. Gases contained in the blood, 300; oxygen and hydrogen, action of fermentation on, 607. Gentianin, on, 221. Geological Society, 86, 284, 433, 508, 564. Geology: — fossil quadrumana, 34; addi- tional fragments of the Siv atherium, 40 ; fossil fishes in the Lancashire coal-field, 86 ; geology of Zante, 87 ; on the form- ation of mould, 89 ; on a hitherto un- observed structure in certain trap rocks, 106 ; on the phenomena of mineral veins, 125 ; unity of the coal deposits of Eng- land, 127 ; on indications of recent ele- vations in Guernsey and Jersey, 284 ; on the great basaltic district of India, 286 ; Rev. W. Whewell's address at the anni- versary of the Geological Society, 434, 508 ; descriptive geology, 508 ; geologi- cal dynamics, 517; theory of volcanos, 533 ; of Devonshire, 510, 565» 569; of Mazunderan, 571 ; of the Birmingham and Gloucester railway line, 573 ; theory C2 612 INDEX. of volcanic phenomena, 576 ; insulated masses of silver, 578 ; peat bogs and sub- marine forests of Bourne Mouth Valley, 579; of Asia Minor, 581; remarkable dikes of calcareous grit, 584; connection of volcanic phenomena, 584 ; on the dis- location of the tail of many Ichthyo- sauri, 590. Geometry, analytical, 602. Giraud(H.)on teriodide of chromium, 321. Glass, action of sulphate of ammonia on, 608. Gould (J.), descriptions of various birds^ 215, 444, 527, 596, 598. Gresham College, Prof. Pullen's lecture on astronomy, 454. Gregory ( Dr.) examination of eblanine, 98 ; on some remarkable salts, 102. Grey (Lieut.) on the meteorology of Tene- rirte, 291. Hall (Col.), meteorological observations made in Colombia, 148. Hallymeter, for the examination of malt liquors, 218. Hamilton (Sir W.) exposition of the argu- ment of Abel respecting equations of the fifth degree, 116; inaugural address de- livered before the Royal Irish Academy, 368. Hamilton (W. J. ) on the geology of part of Asia Minor, 581. Hare (Dr.) on sulphurous asther and sul- phate of astherine, 474. Hatchetine, composition of, 338. Heat, on repulsion by, 317; its influence on the circulation of the Chara, 457 ; re- searches on, 545. Henwood (W. J.) on the phenomena of mineral veins in Cornwall, 125. Herberger (M.) on cetrarin, 296. Heriades campanularum, 1 8. Herschel (Sir J.) on the remarkable in- crease of magnitude of »; Argus, 521, 526 ; on the theory of volcanic pheno- mena, 576. Hess (M.) on the fermentation of sugar of milk, 139. Hogg (J.), specimen of a thermoraetrical diary, 489. Home (Sir J.), magnetical observations made in the West Indies, &c,, 206. Hood's (C.) treatise on warming buildings, 202. Hunt (R.) on tritiodide of mercury, 27. Hylaeus signatus, 18. Hymenoptera, economy of several species of, 14. Hypophosphomesitylous acid, 101. Impressions from feathers, process for ta- king, 451. India, geology of, 514; on the black cot- ton soil of, 430; on the great basaltic district of, 286. Iodide of silver, new property of, 258. Indigo, on the manufacture of, 264. Iridium, method of dissolving, 141. Iron : — its action at a high temperature on benzoic acid, 460; on camphor, 460; peculiar voltaic condition of, 48 ; prot- oxide of, its action on protoxide of cop- per, 299. Isoraorplious substitution, on an apparent case of, 406, 407. Ivory (J.) on ellipsoids, 356. Jamaica, flora of, 263. Jerrard (G. B.) on the occurrence 'of the form -, 345. Jervine, a new vegetable base, 29. Johnston (Prof.) on the equivalents of pot- ash, soda, and silver, 324 ; on Hatchet- ine, 338 ; on the composition of Midule- tonite, 261 ; on the dimorphism of chro- mate of lead, 387 ; on the composition of Ozocerite, 389 ; on an analogy in atomic constitution between the earthy carbonates and alkaline nitrates, 480; composition of retin asphalt, 560. Johnstone (Dr.), notice of the late, 277. Kane (Prof.) on the combinations derived from pyroacetic spirit, 100, 107; on Du- masine, 108. Kelly (Dr.) on low fogs and stationary clouds, 355. Kennedy (A.) on the economy of several species of hymenoptera, 14. Knox (G. J., and Rev. T.) on fluorine, 105. Lactic acid in soar-crout, 1 42. Laminaria digitataj on the reproduction of the frond, 96. Laming (R.) on the primary forces of elec- tricity, 486. Lamont (Dr.) on the value of the mass of Uranus, 522. Latham (Dr.), notice of the late, 274. Lead, dimorpliism of the chromate of, 387 ; new acetate of, 133; oxalo-nitrate of, 459 ; oxide of, and oxide of silver, defi- nite combination of, 217. Leithead's Electricity, review of, 127. Lens, crystalline, on the, 22. Liebig (M.) on lactic acid in sour-crout, 142 ; on the constitution of some organic acids, 381. Light, absorption of, on Von Wrede's e: - planation by the undulatory theory, 114; its intensity in the neighbourhood of a caustic, 452 ; on the dispersion of, 367 ; undulatory theoi*y of, 10. Lime, carbonate of, its crystalline form, 465, 470. Linnaean Society, 92, 531. Liquids, maximum density of, 1. Lloyd ( Prof. ) on the aurora borealis, Feb. 18, 98; account of the magnetical ob- servatory at Dublin, 119. INDEX. 613 Lubbock (J. W.) on the wave-surface in double refraction, 47 ; on the divergence of the numerical coefficients in the lunar theory, 133; on the variation of the ar- bitrary constants in mechanical problems, ti55. Luminosity of the ocean, on the, 212; of the human subject after death, on the, 420. Lunar nutation, determination of the con- stant of, 1 10. Lunar theory, on the divergence of the nu- merical coefficients, 168. Luxford (G.) on the discovery of Cucuba- lus baccifer in the Isle of Dogs, 93. Magnetic contact-breaker, description of a, 18. Magnetical apparatus, improvements in, 380. Magnetical observations, places fixed on by the Royal Society for making obser- vations, 347. Magnetical Observatory at Dublin, 119. Madeira, on the fishes of, 526. Magnus (M. ) on the gases contained in the blood, and on respiration, 300. Malaguti (M.) on the action of chlorine on aethers, 297 ; on camphoric acid, 297. Malcolmson (J. G.) on the great basaltic district of India, 286. Mallet (Mr.) on an unobserved structure in certain trap rocks, 106. Malt liquors, examination of, 218. Marchand ( R. F. ) on a new method of ob- taining chrome alum, 218. Martin (Mr.) on the Felis Darwinii, 213; on the proboscis monkey, 592. Matteucci (M.), researches relative to the torpedo, 196; on the chemical composi- tion of the electrical apparatus of the tor- pedo, 256 ; on thermo-electric pheno- mena, 295. Medusae, luminous, 213. Mercury, analysis of double salts of, 235 ; tritiodide of, 27. Mesityl, oxide of, 100. Metals, on the colours of, 298. Meteoric stones, in Brazil, 462. Meteorology : — observations, 143, 223, 303, 382, 463, 543 ; low temperature of Jan. 1838, 302; observations made at Ber- muda in 1836-37,42; observations made in Colombia, between 1820 and 1830, 148; meteorology of Tcneiiffe, 291 ; de- scription of a new barometer, 204 ; spe- cimen of a thermometrical diary, 498. Meteorological Society, 291, 601. Meteorological table : — for Nov. 144; for Dec. 224 ; for Jan. 304 ; for Feb. 384 ; for Mar. 463 ; for Apr. 544. Meteors of Nov. 12, 85. Mcyen (Prof.) on the progress of vegetable physiology in 1836, 53. Milk, sugar of, on its fermentation, 139. Middletonite, on, 261. Mineral veins, on the phenomena of, 125. Mont Blanc, on an optical phenomenon observed at, 122. Mora tree of British Guiana, 532. Morichini (Prof.), notice of, 280. Mosses of Upper Assam, 532 ; on the ex- istence of stomata in mosses, 533. Mould, on the formation of, 89. Mus, new species of, 443. Nautilus, pearly, on the theory of the ac- tion of the siphuncle in the, 503 ; the paper nautilus, 601. Needles rendered magnetic by the nerves, 223. Newbold (Capt.) on the black cotton soil of India, 430. Newton's rings, 28, 485. Nile, plan for exploring the western branch of the, 543. Nitre, its formation in extract of quassia, 140 ; new property of, 145. Nitric acid, its action on iron, 49 ; its ac- tion on bismuth, 305. Noad (H. M.) on the peculiar voltaic con- ditions of iron and bismuth, 48. North-west passage, discovery of the, 542. Ocean, on the phosphorescence of the, 211. Observatory, magnetical, at Dublin, 119. Odynerus quadratus and O. bidens, habits of, 17. Oil, empyreumatic, 101. Ogilby (W.) on the quadrupeds of Austra- lia, 95. Optical phenomena observed at Mont Blanc, 122. Organic acids, constitution of, 381. Organic compounds, method of analysing, 31, 232. Ornithology: — ground finches, 215; He- mipodius melanogaster, 215; new spe- cies of parrot, 215; new raptorial birds, 215; new species of Fissirostral birds, 444; the Apleryx, 444; Australian birds, 444 ; on the habits of the Vultur aura, 447 ; Rhea Darwinii, 450 ; Rhea Ame- ricana, 450; simple process for taking im- pressions from feathers, 451 ; Humming birds, 526 ; new species of Ortyx, 527 ; Podargus stellatus, 527 ; Pteroglossus Gouldii, 528; British wagtail (Mota- cilla Yarrellii) 596, 598 ; Motacilla leu- copsis, 598 ; Corvus nobilis, Ortyx gutta- ta, Thamnophilus fuliginosus, and Den- drocitta rufigaster, 598. Osmia bicornis, and O. spinulosa, 18. Ostrogradsky (M.) on a singular case of the equilibrium of fluids, remarks on, 385. Otus brachyotus, on the habits of, 104. Owen (R.)» the Wollaston medal awarded to, 433 ; on the dislocation of the tail in 614 INDEX. the skeletons of many ichti^iyosauri, 590; on tlie cranium of an oran outang, 599 ; examination of a foetal kangaroo, 600. Owl, short-eared, habits of, 104. Oxalo-nitrate of lead, 459. Oxide of silver and oxide of lead, definite combination of, 217. Oxygenin the atmosphere, on the quantity of, 397. Ozocerite, composition of, 389. PalsRoniscus Egertonii, 86. Parrot, new species of, 215. Payen (M.) on a new acetate of lead, 133. Pelouze (M.) on the products of the de- composition of cyanogen in water, 339. Pemphredon lugubris, P. Morio, and P. unicolor, 17. Phaenogaraous plants, on the development of the organization in, 172, 241, 292. Phillips (K.), on a new acetate of lead, 134; on isomorphism, 407. Phosphorescence of the ocean, on the, 211. Photometer, on the method of computing the results of experiments with the, 484. Physalia pelagica, 528. Physiology, vegetable, progress of, 53. Planche (M.) on the formation of nitre in extract of quassia, 140. Polarization: —cause of elliptical, 10; in the crystalline lens after death, 22; of heat by tourmaline and by refraction, 549 ; by reflection, 553. Polyhedron, solid, on certain relations in a, 323. Portlock (Capt.) on the habits of the short- eared owl, 104. Potash, bicarbonate of, its preparation, 216; on the equivalent of, 324. Potassium, chloride of, detection of salt in, 130; ferrocyanide of, its action on sul- phovinates and sulphomethylates, 102. Potter (R.), reply to Mr. Wheeler on the method of computing the results of ex- periments with the comparative photo- meter, 484. Powell (Prof.) on repulsion by heat, &c. 317 ; on Von Wrede's explanation of the absorption of light by the undulatory theory, 114; on the dispersion of light, 367. ' Pratt (Rev. J. H.) on the equihbrium of fluids, 385. Prevost (Dr.) on the muscular fibre, 293. Prideaux (J.) on the Kauri or Cowdee re- sin from New Zealand, 249. Projectile weapon of the native Australians, 329. Psen atratum, 17. Pullen's ( Prof.) Gresham lectures, 454. Pyramids of Gizeh, 379. Pyroacetic spirit, on the compounds derived from, 100, 107, 109. Quadrumanous animal, fossil, 34. Quassia, formation of nitre in extract of, 140. Quassin, on, 222. Quekett (E. J.) on the genus Chara of Hooker, 97. Reflection, polarization by, 553. Refraction, polarization by, 549. Refraction, double, on, 47, 145. Respiration, on, 300. Repulsion by heat, on, 317. Resin, Kauri or Cowdee, from New Zea- land, 249 ; its use in the arts, 253. Retin Asphalt, composition of, 560. Retinic acid, salts of, 562. Reviews : — Leithead's Electricity, 127 ; Macfadyen's Flora of Jamaica, 263 ; Hood's Treatise on Warming Buildings, 202 ; Curtis's Guide to an Arrangement of British Insects, 202 ; Agnew on the Pyramids of Gizeh, 379; Levy's De- scription of Heuland's Collection of Minerals, 536; Young*s Analytical Geo- metry, 602. Rhea Darwinii, 450; Rhea Americana, 450. Richardson (M.) on the products of the de- composition of cyanogen in water, 339. Riddle (Mr.) on the longitude of the Edin- burgh observatory, 525. Rigg (R.) on analysing organic com- pounds, 31, 232. Ritchie, (Dr.) notice of the late, 275. Robinson (Dr.) on the determination of the constant of lunar nutation, 1 1 0. Robinson and Russell on the mechanism of waves, 112. Rodentia, new, 445. Rose (M.) on the detection of metallic chlorides in bromides and iodides, 136; on some new compounds of chlorine, 220 ; on chloride of tungsten, 461 ; on the formation of calc spar and arragonite, 465. Rothman (R. W.) on a very ancient solar eclipse observed in China, 282. Royal Astronomical Society, 280, 521. Royal Institution, 451, 533. Royal Irish Academy, 97, 368. Royal Society, 204, 269, 347, 426. Sabine (J.), notice of the late, 276. Salt, its detection in chloride of potas- sium, 130; process for the purification of, 218. Salts, double, of mercury, analysis of, 235 ; efflorescent, absorption of water by, 130 ; on some remarkable, 102; of retinic acid, 562. Sapyga 4-guttata, ]5. Schoenbein (Prof.) on the voltaic relations of certain peroxides, platina, and inactive iron, 225 ; on the current electricity ex- cited by chemical tendencies, 311. Schleiden (Dr.) on the development of the INDEX. 615 organization in phxnogamous plants, 172, 241,292. Scoresby ( W.) improvements in magnetical apparatus, 380. Scrope (P.), voltaic theory, 536. Sea-water, on the maximum density of, 7. Sells (W.) on the habits of the Vultur aura, 447. Silver, iodide of, new property of, 258 ; on the equivalent of, 324 ; oxide of, and ox- ide of lead, definite combination of, 217. Simon (E.) on Jervine, a new vegetable base, 29. Simpson and Dease's discovery of the North- west passage, 542. Siphuncle in the pearly nautilus, on the action of the, 503. Sivatherium, notice of additional fragments of the, 40. Smith (A.), method of finding the equation to Fresnel's wave-surface, 335. Soane (Sir J.), notice of the late, 278. Soda, on the equivalent of, 324. Solar eclipse, very ancient, 282. Solutions, saline, maximum density of, 7. Soubeiran (M.) on sulphuret of azote, 134. Spiders, entombed by the Trypoxylon, 1 5. Springs, intermitting, on the phenomena of, 364. Stigmus troglodytes, 16. Strickland ( H. E.) on the geology of the island of Zante, 87 ; on some remarkable dikes of calcareous grit at Ethie, 584. Suffolk, geological survey of, 512. Sugar of milk, on its fermentation, 139. Sulphomesitylates, 100. Sulphovinates and sulphomethylates, action of ferrocyanide of potassium on, 102. Sulphuret of azote, 134. Sulphurets, metallic, on their employment in analysis, 137. Sussex (Duke of), address on the anniver- sary of the Royal Society, Nov. 30, 1837, 269. Sylvester (J. J. ) on the optical theory of crystals, 73, 341. Talbot (H. F.) on a new property of nitre, 145 ; on a new property of the iodide of silver, 258. Tartaric acid, constitution of, 381. Taylor (T.) on two calculi composed of cystic oxide, 337 ; on urinary calculi, 412. Tadpoles, mode of closure of the gill-aper- tures in, 527. Tartaric and paratartaric acids, 605. TenerifTe, rrieteorology of, 291. Thermo-electric phenomena, on, 295. Thermo electricity, decomposition of water by, 541. Thermo-multiplier, use of, 545. Thermometrical diary, specimen of a, 489. Tiarks (Dr.), notice of the late, 274. Tide-gauge, new, 430i, Tides, on the, 351 ; Prof. PuUen's lectures on the, 454 ; on the mechanism of waves, 112. Tin, preparation of protoxide of, 216. Torpedo, chemical composition of the elec- trical apparatus of, 256 ; researches re- lative to the, 196. Tovey (J. ) on the cause of elliptical po- larization, 10 ; on the optical theory of crystals, 259. Toxodon Platensis, 516. Trevelyan (W. C.) on indications of recent elevations in Guernsey and Jersey, 284. Trommsdorfr(M.) on gentianin, 221. Trypoxylon figulus and T. clavicenim, habits of, 15. Tungsten, chloride of, 461. Turner (Dr.), notice of the late, 275, 436. Valentine ( W.) on the existence of stomata in mosses, 533. Vegetable physiology, progress of, 53. Vertebrata, subdivided into five classes, 92. Volcanic phenomena, theory of, 576 ; on the connexion of, 584. Volcanos, on the theory of, 533. Voltaic combinations, on, 364 ; conditions of iron and bismuth, 48 ; relations of certain peroxides, platina, and inactive iron, 225. Von Hoff (M.), notice of the late, 439. Vultur aura, habits of the, 447. Undulatory theory, 10, 114, Uranus, value of the mass of, 522. Walter (M.) on the bichromate of -per- chloride of chrome, 83. Ward (Mr.) on the reproduction of the fronds of Laminaria digitata, 96. Water, its absorption by efflorescent salts, 130; its decomposition by thermo-elec- tricity, 541 ; on the maximum density of, 1. Waterhouse ( G. R. ) on a new species of Mus, 443; on new Rodentia, 445; on several undescribed quadrupeds, 596. Watkins (F.) on electro-magnetic motive machines, 190; on' the low temperature of Jan. 1838, 302 ; on the decomposition of water by thermo-electricity, 541. Watson (H.) on the absorption of water by efflorescent salts, 130; detection of common salt in chloride of potassium, 132. Watson (J.) mode of exhibiting the colours of thin plates, 28. Waves, mechanism of, 112. Wave-surface in double refraction, 47. Weaver (T.) on the geological relations of North Devon, 569. Westwood (J. O. ) on the family of Fulgo- ridae, 93 ; on several new species of in- sects belonging to the family of sacred beetles, 441. 616 INDEX. Wharton (W. L.) on the phenomena of intermitting springs, 364. "Whewell( Rev. W. ), Royal medal adjudged to, 269, 351 ; address at anniversary of the Geological Society, 434, 508. Williamson (W. C.) on fossil fishes in the Lancashire coal-field, 86. Woehler ( Prof. ) on the preparation of bi- carbonate of potash, 216 ; on the definite combination of oxide of silver and oxide of lead, 217. Worm, vegetable mould produced by the digestive process of the, 90. Wrede's theory of the absorption of light, on, 114. Wright ( T. ) on Dr. Buckland's theory of the action of the siphuncle in the pearly nautilus, 503. Xanthophylle, the colouring matter of leaves in autumn, 135. Young's (J. R.) Analytical Geometry, 602. Zante, on the geology of, 87. Zinken (Von), on a new locality of arse- nical copper in Chili, 217. Zoological Society, 211, 441, 526, 592. Zoology: — on vertebrate animals, 92; Au- stralian quadrupeds, 95 ; on three speci- smens of the genus Felis, 213 ; new spe- cies of opossum, 215; new species of fox, 441 ; Dasypus hybridus, 442; un- described species of the genus Mus, 442 ; small Rodents, 445 ; on the genus Ga- lictis, 529; the Once of Buffbn, 530; new species of Sciuroptera, 530 ; new species of fox, 530 ; new species of Gib- bon, 530 ; quadrupeds from South Afri- ca, 531 ; proboscis monkey, 592 ; on several undescribed quadrupeds, 596 ; on the genus Kemas, 598 ; cranium of an orang outang, 599 ; uterine foetus of a kangaroo, 600; paper nautilus, 601. END OF THE TWELFTH VOLUME. LONDON: PRINTED BY RICHARD AND JOHN K. TAYLOR, RED LION COURT, FLEET STREET. FLAltlMAM. GENERAL INDEX TO THE LONDON AND EDINBURGH PHILOSOPHICAL MAGAZINE AND JOURNAL OF SCIENCE. BEING A CONTINUATION OF TILLOCH'S PHILOSOPHICAL MAGAZINE, NICHOLSON'S JOURNAL, AND THOMSON'S ANNALS OF PHILOSOPHY, For volumes L to XIL FROM JULY 1832 to JUNE 1838. LONDON: PRINTED BY R. AND J. E. TAYLOR, RED LION COURT, FLEET STREET. sold by longman, orme, brown, green, and longmans ; baldwin and cra- dock; cadell ; sherwood, gilbert, and piper; simpkin and Marshall; B.FELLOWES ; S. HIGHLKY ; WHITTAKER AND CO.; AND J. B. BAILLIERE, LONDON : AND BY A. AND C. BLACK, AND THOMAS CLARK, EDINBURGH ; SMITH AND SON, GLASGOW : MILIKEN AND SON, AND HODGES AND M'ARTHUR, DUBLIN : AGENT IN PARIS, G. W. M. REYNOLDS, FRENCH, ENGLISH, AND AMBRICAN LIBRARY, 55, RUE NEUVE ST. AUGUSTIN. 1839. GENERAL INDEX TO THE LONDON AND EDINBURGH PHILOSOPHICAL MAGAZINE AND JOURNAL OF SCIENCE. THIRD SERIES. The numeral letters refer to the volumes, the figures to the pages. AM. H., description of the harvest • bug, ix. 15. A. R., on Newton's rings, vii. 363, 474. Abbott ( R.) on the variation of a triple integral, xii. 363. Abel's theorem, on some elementary ap- plications of, vi. 116; exposition of his argument respecting equations of the fifth degree, xii. 116. Absorption, on, viii. 58. of light, on Von Wrede's theory of^ xii. 114. ; ' Acacia, on the strength of, i. 17. Acalepha, proposed distribution of the families of, vii. 68. Acetate of copper, new species of, ix. 395. Acetic acid, formed from carbonic oxide and hydrogen, ii. 155. Achromatic lens, negative, its application to telescopes, &c. v. 452. light in solar and oxyhydrogen mi- croscopes, X. 184. object glass, double, vii. 161. microscope, viii. 70. Achromatism of the eye, vi. 161, 247. Acids ; — acetic, ix. 78, 111 ; xi. 513. dif- ference between and formic, iii. 73; ambreic and cholesteric, iii. 382 ; am- pelic, ix. 406; anchusic, analysis of, iii. 382; anilic, x. 325; apochrenic, V. 238 ; arsenious, vi.237 ; ix. 230; xi. 482; arsenovinic, viii. 447; benzoic, ix. 78 ; bombic, x, 323; boracic, x. 419; bromine, new acid of, viii. 588 ; cam- phoric, xii. 297, — anhydrous, xi. 221 ; camphovinic, xi. 221 ; carbonic, viii. 446; ix. 12,77,78,111, 153; x. 158; cholesteric, iii. 382; chloro-carbonic, iv. 385; chloro-chromic, ix. 12; chloro- clomic, ix. 152 ; chrenic, v. 238 ; chro- mic, ix. 152; xi. 489, — compounds of, with metallic chlorides, iii. 235 ; ciU'ic, xii. 381 ; formic, vi. 399; ix. 149; xi. 399, — preparation of, iii. 313; fumar, xi. 164; gallic, vi. 319; xi. 323 ; hy- driodic, viii. 191; ix. 76; hydrobromic, ix. 149 ; hydrochloric, viii. 353 ; ix. 78, 151,255; hydrocyanic, vi. 97; vii. 400; ix. 314 ; hydrofluoric, ix. 77, 107, 152; hydroleic, ix. 153; hydrostearic, ix. 153; hydrosulphuric, ix. 255, 316; hydroxanthic, ix. 317; hyponitrous.ix, 77 ; hypophosphomesitylous, xii. 101; iodic, ix. 76; x. 93; xi. 219; iodous, iv. 392 ; lactic, iv. 233 ; xii. 142 ; lam- pic, xi. 512 ; lithic, v. 465; malic, iv. 74; margaric, ix. 153; mellitic, x. 1 59 J metamargaric, ix. 153 ; molvbdic, ix. 252; monohydrated sulpho-carbe- theric, ix.3l7; muriatic, vii. 400; ix.l2, 232,233, — in fluor spar, v. 78 ; new, xii. 220; nitric, ix. 12,53, 77, 113, 122,259; X. 172, 269, 276, 326 ; xi. 554 ; nitrohy- drochloric, ix. 113; nitrosulphuric, x. 489; oenanthic, x. 418, 422; organic, a new, xi.564;oxalhydric,iv. 74;xi. 142; oxalic, V. 445; ix. 78, 155; paratarta- ric, xii. 605; periodic, x. 325; pho- sphoric, ix. 75, 154, 261 ; X. 217, 218 ; phosphovinic, iii. 73 ; ix. 396 ; picric, X. 325; polygalic, xi. 561; pyroge- nous, iv. 385 ; pyromucic, vii, 429 ; pyrotartaric and tartaric, v. 397 ; re- tinic, xii. 560 ; suberic, viii. 443 ; suc- cinic, vii. 238 ; sulphindylic, x. 320 ; sulphocarbic, ix. 318; sulphocetic, ix. 154; sulphocyanic, ix. 443 ; sulpho- leic, ix, 153; sulphomargaric, ix. 153; sulphomethylic, vii. 397 ; sulphonaph- talic, xi. 565 ; sulphopurpuric, x. 324; sulphostearic, ix. 153 ; sulphovinic, ix. 154,318; sulphuric, vi. 97; ix. 12, 78, 87, 152, 153, 154,261, 322, 396; x. 324, — anhydrous, x. 157; xi. 321, 566^ — English, vii. 235, — manufacture of, iii. 115; sulphurous, ix. 543; x. 235, — an- GENERAL INDEX OF VOLS. 1 12 OF THE hydrous, Ti. 321, 566; tartaric, xii.381 ; tartaric and pyrotartaric, v. 397 ; tel- luric, iv. 76; titanic, vi. 113, 201; tungstic, ix. 232 ; valerianic, v. 396 ; xanthomethilic, x. 488. Acoustic figures, ii. 144. Acoustics, on the production and propa- gation of sound, vi. 25. Adam ( Dr. W. ) on the osteological forms in adults of the human species, iii. 457 ; on human osteology, vi. 57. Addams (R.) on a peculiar optical phae- nomenon, V. 373; on the repulsive ac- tion of heat, vi. 415; on the action of cold air in maintaining heat, xi. 446. Addison (W.) on an extraordinary me- teor seen at Malvern, iii. 37. Aerial currents, on Mr. Whewell'sinstru- ments for registering, xi. 474. JEther, formation of, viii. 258 ; by fluo- ride of boron, ii. 77. , hydrocyanic, v. 397 ; hydrosulphu- ric and hydroselenic, ix. 318; iodic, ii. 415 ; cenanthic, x. 418 ; sulphurous, xii.474. ■, spark during the freezing of water by, iv. 156. , action of bromine upon, ix. 149; facts relative to, ix. 395. .Slthereal oils, preparation of, xi. 159; elementary constituents of, xi. 161. Others, action of chlorine on, xii. 297. ^therine, sulphate of, xii. 474. Africa, on the ring money of, xi. 132. Afzelius (A.) notice of, x. 470; xii. 279. Agassiz ( Dr.) on the growth and bilateral symmetry of Echinodermata, v. 369 ; on the classification of fish, ▼. 459; on Lepisosteus, vi. 384; on fossil fishes, vii. 485 ; on the principles of classifi- cation in the animal kingdom, vii. 491 ; on the fossil beaks of four species of Chimaera, viii. 6 ; on fossil fish found in English collections, viii. 72 ; the Wollaston Medal awarded to, viii. 310. Agnew on the pyramids of Gizeh, xii. 379. Air, its action on lead, v. 81 ; vibration of in a cylindrical tube, vii. 300 ; in- fluence of its artificial rarefaction and condensation in some diseases, viii. 62; action of mushrooms on, viii. 82. , atmospheric, on the quantity of oxygen in, xii. 401. , compressed, its effects on the hu- man body, ix. 147. , heated, its conducting power for electricity, ix. 176, 452. Airy (Prof.) on a new analyser, and its use in experiments of polarization, i. 75 ; on the phaenomena of Newton's rings formed between substances of different refractive powers, i. 400 ; ii.20 j remarks on Mr. Potter's experiment ort interference, ii. 161, 451 ; reply to, ii. 276; researches into the numerical va- lue of the mass of Jupiter, ii. 314 ; iii. 233 ; iv. 383 ; account of an aurora bo- realis, ii. 315 ; answer to Sir D. Brew- ster on the undulatory theory of light, ii. 419 ; Report on the progress of as- tronomy during the present century, ii. 457; deductions founded on observa- tions of the aurora borealis of Septem- ber 17 and October 12, iii. 461 ; on the solar eclipse, July 16, 1 833, v,305; on the position of the ecliptic, v. 307 ; on the parallax of a Lyraj, xii. 280; on the intensity of light in the neighbour- hood of a caustic, xii. 452. All)umen, new combinations of, ix. 109; nature and properties of, x. 85 ; action of electricity on, x. 357. and bichloride of mercury, com- pound of, X. 420. Alcohol, a new acid formed by its com- bustion around an incandescent pla- tina wire, xii. 220. and indigo, their analogy consi- dered in their combination with sul- phuric acid, X. 324. Aldehyd, a new compound, viii. 83. Alepisaurus, a new genus of fishes, iii. 379. AlgEB, their mode of generation, xK 385. Algebraic equations, vKi. 402. elimination, viii. 538 ; theorem of, ix. 28. Alison (Dr.) on the vital powers in arte- ries leading to inflamed parts, and on the cause of death in asphyxia, vii. 5lO. ( R. E.) on the earthquake of Chili, Feb. 20, 1835, viii. 74. Alkalies, vegetable, ammonia in, vi. 78 ; action of iodine on the, x. 500. xi.216. and metallic oxides, on the com- binations of sugar with the, xi. 152. Alkaline nitrates and earthy carbonates, analogy in atomic constitution be- tween, xii. 480. Allan ('hicmas), memoir of, iii. 317. Allanite, analysis of, vi. 238. Alloys, fusing points of, i. 264. of iron and copper, vi. 81. Almonds, bitter, composition of oil of, iii. 389. iv. 70. Aloe plant of Socotra, x. 226. Alum, a new variety of, xii. 103, 124 ; chrome alum, newmethod of obtaining, xii. 218. Aluminum, atomic weight of, vii. 75. Ambreine, on, iii. 382. America, researches in the geology of. LOND. AND EDIN. PHILOSOPHICAL NfAGAZlNE, 1832 1838. iv. 453 ; appearance of elevation of land on the west coast of, vii. 318. America, North, on the carboniferous series of, ix. 124, 407 ; on the ancient state of, xi. 201 ; on the western coast of, xi. 91. — — , South, geology of, xii. 516. Amidone, solubility of, x. 247. Ammonia and formic acid formed from hydrocyanic acid and cyanurets, i. 83. ■ ' and carbonic acid, on the combi- nations of, iii. 457. — — , in the vegetable alkalies, vi. 78 ; muriate of, its action on certain sul- phates, vi, 235 ; muriate of, ix. 232; hydrochlorate of, solubility of carbo- nate of lime in, ix. 540 ; iodate of, ix. 443 ; solvent action of muriate and nitrate of, x. 95, 17S, 333. , its action on the chlorides and oxides of mercury, viii. 495. — — with anhydrous salts, on the com- binations of, xi. 141. , sulphate of, its action on glass, xii. 608. Amniotic acid, on the true source of, &c., i. 319. Ampelic acid, xi. 406. Ampelin, on, xi. 407. Ampere (M.) on heat and light as the results of vibratory motion, vii. 342. Amphibole, analysis of, x. 238. Amylum, experiments on, xi. 442. Analyser, a new, and its use in experi- ments of polarization, i. 75. Analyses : — employment of insoluble salts in, vi. 79; of osmiridium and al- lanite, vi.238 ; of amineral water from the island of St. Paul, vi. 312. Analysis, a new theorem in, x. 28 ; on the employment of metallic sulphurets in, xii. 137; chemical, xii. 229 ; of some double salts of mercury, xii. 235. Analysing organic compounds, method of, xii. 31,232. Anatifa vitrea, on its occurrence on the Irish coast, xi. 135. Anchor, found at Seaton, x. 10. Anchors, Pering'simprovementsin, i. 74. Andrews (Dr.) on the conducting power of certain flames and of heated air for electricity, ix. 176; on the action of nitric acid on certain metals, xi. 554 ; on the action of nitric acid upon bis- muth, &c., xii. 305 ; on thermo-elec- tric currents, x. 433. (T.) on the biood of cholera pa- tients, i. 295. Anemometer, new, vii. 315. and rain gauge, on a new regis- tering, xi. 476. Anhydrous camphoric acid, xi. 221 ; sul- phuric and sulphurous acids, combi- nation of, xi.321. Anions, v. 429. Aniiiialcula, on the minuteness of, ii. 64. Animals, on the structure of, vi. 4,90; on the hereditary instinctive propensi- ties of, xi. 96; on the crystalline lenses of, after death, xi. 97 ; thermometer for determining minute differences in, viii. 57. Anorthite and biotine, identity of, x. 368. Antelope, Abyssinian, ix. 142; Indian, ix. 306 ; Chiru, ix. 306. Anthon (M.) on the employment of me- tallic sulphurets in analysis, xii. 137. Antimoniuretted hydrogen, x, 343. Antimony, the reflective powers of glass of, iv. 6 ; on oxychloride of, vii. 332 ; on a supposed new sulphate and oxide of, viii. 476 ; crystallized oxychloride of, viii. 585. Antimonial copper, ix. 149. Antrim, geology of the county of, i. 228. Apjohn (Prof. J.) on the dew-point, vi. 183; vii. 266, 313, 470; formula for inferring the specific heat of gases, error in, viii. 21 ; on certain statements relative to his hydrometrical researches made by Dr. Hudson, ix. 187 ; exa- mination of eblanine, xii. 98 ; on the specific heats of the aeriform fluids, xii. 101 ; on a new variety of alum, xii. 103, 124; on the specific heats of ela- stic fluids, vii. 385. Apochrenic acid, in the mineral waters of Porta, V. 238. Arachnida, on a new species of, i. 190. Arago (M.) on shooting stars, xi. 567. Araneidae, undescribed genera and spe- cies of, iii. 104, 187, 344, 436; v. 50; viii. 481 ; x. 100. Arch, oblique, x. 74, 167. , skew, construction of, viii. 299. Architecture, Gothic, progress of, vi. 395. , on the entablature of Grecian buildings, viii. 430; Gothic, viii. 449. Argonauta, Linn., x. 303; on the animal of, vi. 385. hians. Lam., description of the shell and animal of, ix. 301. Aricina, M. Pelletier on, iii. 311. Armadillo, on the weazel-headed, ii.69. Arragonite, artificial crystals of, ix.230. , on tlie formation of, xii. 465. Arseniates, phosphates, and mo.iilications of phosphoric acid, iii. 451, 459. Arsenic in English sulphuric acid, vii. 235; in phosphorus, vii. 331; va- porization of, viii. 190; Marsh's test for, X. 353. , vegetation in a solution of, x. 324. Arsenical copper, xii. 217. GENERAL INDEX OF VOLS'. 1 — 12 OF THE Arsenious acid, reducing powers of, ix. 230; solubility of, xi. 482; peroxide of iron, an antidote to, vi. 237. Arsenovinic acid, viii. 447. Arteries leading to inflamed parts, on the vital powers in, vii. 510. Artesian wells, temperature of, v. 237. Artificial crystals and minerals, method of making, ix. 229, 537. , results of experiments on the production of, x. 171. Artificial substance resembling shell, x, 301. Ascent of mountains, on the, x. 261. Ashes of plants,'on structure in the, xi. 1 3. Asia, on the negroes of, i. 466". Minor, geology of, x. 68. Asparagiu and aspartic acid, analysis of, ii. 481. Asphyxia, on the cause of death in, vii. 510. Assay of silver, vii. 425. Astronomical Society, grant of a royal charter to the, i. 234 ; proceedings of, ii. 222, 378, 475; v. 300; vi. 221, 305, 449 ; vii. 69 ; ix. 291 ; x. 227. Astronomy, researches in physical, i. 69; Dr. Pearson's introduction to practi- cal astronomy, i. 370, 450 ; on the pro- gress of, during the present century, ii. 457; latitude and longitude of the Cape observatory, iii. 231 ; positions of stars near the south pole, iii. 231 ; on the mass of Jupiter, iii. 233 ; on the visibility of stars by day, iii. 238 ; on the attraction of spheroids, iii. 235, 282 ; the elementi. of ^ Botitis and of y Virginis, iii. 290 ; on a standard of optical power, iii. 291 ; Dr. Olberson the return of Halley's comet, vi. 45 ; astronomical refractions, vi. 1 42 ; Dr. Halley's astronomical observations, vi. 221 ; some particulars of the life of Dr. Halley, vi. 306 ; an equal altitude instrument, vi. 449 ; letter from Sir John Herschel, dated Cape of Good Hope.vi. 450; Prof.Encke onOlbers's method of determining the orbits of comets, vii. 7, 123, 203, 280; cata- logue of comets, vii. 36 ; Snow's ca- talogue of 76 stars, vii. 69 ; comets observed at Paramata,vii.69; Halley's comet, vii. 139, 236 ; viii. 148, 173; ix. 292; ephemeris of Halley's comet, ix. 296 ; new method of reducing lunar observations, vii. 241; viii. 373 ; im- proved astronomical clock, viii. 71 ; Newton and Flamstead, viii. 139, 211, 218, 225 ; the aurora borcalis of Nov. 16, 1835, viii. 134, 236, 350,412,439 ; Dr. Brinkley, viii. 155 ; Mr. Trough- ton, viii. 155 J new observatory at Cata- nia, viii. 256 ; solar eclipse of May 15, 1836, viii. 293, 589. 590; ix. 73; x. 15, 180 ; aurora borealis, ix. 44, 73, 230; X. 75, 76, 77, 265, 494, 495; xi. 194 ; meteors in India, ix. 74 ; on the latitude of Mr. Snow's observatory at Ashurst, ix. 291 ; transits of the moon and stars observed at Argos, ix. 292 ; transit of Mercury over the sun's disc. May 5, 1832, ix. 293 ; Denmark royal medal for cometary discoveries, ix. 294 ; Sir J. Herschel's catalogue of double sttirs observed at Slough, ix. 295 ; Wrottesley's catalogue of the right ascensions of 1318 stars, x. 227 ; projections of maps and charts, x. 229 ; Struve's work on tlie measure of dou- ble stars, X. 229 ; remarkable phaeno- menon that occurs in eclipses of the sun, X. 230 ; on shooting stars, xi. 268, 567 ; determination of the constant of lunar nutation, xii. 110; on the pa- rallax of a Lyrae, xii. 280; on a very ancient solar eclipse observed in China, xii. 282 ; on the repetition of the Ca- vendish experiment for determining the mean density of the earth, xii. 283 ; remarkable increase of magni- tude of the star «, xii. 521, 526; value of the mass of Uranus, xii. 522 ; lon- gitude of the Edinburgh observatory, xii. 525. Atkinson, (J.) on Sir G. S. Mackenzie's remarks on certain points in meteor- ology, viii. 187. Atmosphere, impregnations of, near the sea, iii. 465 ; composition of the,vi. 319; action of mushrooms on the, viii. 82; action of plants upon, viii. 415 ; on the constitution of the, xi. 195; xii. 158, 397 ; on carbonic acid in the, xi. 225. of a white-lead manufactory, expe- riments on, vii. 77. Atmospheric pressure, fluctuations of the height of high water due to changes in the, xi. 195. Atomic weights, on some, i. 109 ; iii. 448. constitution of elastic fluids, v. 33. confusion, ix. 317. constitution, supposed analogy in, between the earthy carbonates and al- kaline nitrates, xii, 481. weight of aluminum, vii. 75. Atropia, iii. 464 j composition of, iv. 239. Attraction, electrical, vii. 304 ; magnetic, vii. 439. Augite, analysis of, x. 237. Aurora Borealis, on the, vii. 304 ; x. 75, 76,77, 265,494,495; of Nov. 16, 1835, viii. 134, 236, 350, 412, 439; ix. 73, 230. LOND. AND EDIN. PHILOSOPIUCAL MAGAZINE, 1832 1838. Aurora Borealis, phaenomena of, xi. 194; pliacnomenon connected with the, ix. •44 ; nature and origin of, vi. 59 ; seen at Woolwich, vi. 230; at Bermuda, xii. 42; on two arches of the, 233; seen at Cambridge, March 13th, 1853, ii. 315; on a brilliant arch of an, iii. 422; deductions founded on observa- tions of those of Sept. 17 and Oct. 12, 1833, iii. 461. Austen (R. A. C.) on the raised beach near Hope's Nose, Devonshire, vi. 63; on the geology of part of Devonshire between the Ex and Berry Head and tlie coast and Dartmoor, ix. 495 ; on the geology of Devonshire, xii. 564. Australia, on the quadrupeds of, xii. 95; projectile weapon of the Australians, xii. 329. Azote, origin of, in animal substances, iv. 237 ; mode of obtaining, iv. 315 ; presence of in seeds, iv. 389. , phosphuret of, vii. 158; sulphuret of, xii. 134. BD. on the path of the boomarang, • xii. 329. Babbage (Mr. C.) on the economy of machinery and manufactures, i. 208 ; on the Temple of Serapis at Pozzuoli, V. 213; views respecting geological cycles, V. 215; notice of a remarkable paradox in the calculus of functions, Mr. Graves' explanation of, ix. 334, 443 ; on some impressions in sand- stone, X. 474. Babel and Babylon, on the distinction between, xi. 68. Babington (Dr.), notice of the late, iv. 442. (C. C.) on new British and Euro- pean plants, viii. 345 ; on some species of Polygonum and Fagopyrum, x. 223; structure of Cuscuta europaea, xii. 531. Babylon and Babel, non-identity of, viii. 506; ix. 34. Bacillariae, doubtful nature of the, xi. 387 ; notice of new discoveries of Ehrt'iibcrg respecting the, xi. 448. Baggy Point, on the raised beaches of, xi. 117. Baily's (F.) paper on the pendulum, i. 379 ; report on Capt. Forster's pendu- lum experiments, iv. 230; account of the astronomical observations made by Dr. E. Halley, at the Observatory, Greenwich, vi. 221 ; description of the Royal Society's new barometer, xii. 204 ; on the repetition of the Caven- dish experiment for determining the mean density of the earth, xii. 283 ; on a remarkable phaenomenon that occurs in total and annular eclipses of the sun, X. 230. Baker (Lieut.) on the fossil jaw of a gi- ganticquadrumanous animal, xi. 33. B.ikcrian lecture for 1833, remarks on, iv. 208. Balani, observations on, iv. 65. Bale (Rev. S.), notice of, x. 464. Ball (R.) on Pentacrinus Europaeusand a species of Beroe, vii. 495 ; on the Seals of Ireland, x. 487. Ball- Pendulum, on the theory of the, iii. 185. Banffshire, on some elevations of the coast of, xi. 209. Barium, peroxide of, ii. 77. Bark, its structure and growth, xii. 54. Barker (Dr. W.) on electric currents passing through platinum wire, vii. 388. (Prof. F.) on certain chemical pro- cesses, vii. 407. Barlow (P.) on the application of the ne- gative achromatic lens to telescopes, &c., V. 452; on the theory of gradients in railways, viii. 97 ; on Lecount's trea- tise on iron rails, viii. 291 ; on gra- dients on railroads, ix. 380 ; on the electro-magnetic conducting power of wires, and on the efficiency of the gal- vanometer for determining the laws of its variation, xi. 1. (P., jun.) experiments on Acacia, i. 17; experiments on timber, remarks on, i. 116; on the motion of steam- vessels, v. 453. (W. H.), experiments on Drum- mond's light, viii. 238 ; on different modes of illuminating light-houses, xi. 94. Barometer, periodical oscillation of, i. 388 ; on a water, i. 387 ; summary of the state of, at Kendal, for 1832, ii. 238; 1833, iv. 398 ; self-registering, viii. 67 ; new, belonging to the Royal Society, xii. 204. Barton (J.) on the inflexion of light, ii. 263; remarks on, ii. 424 ; on the in- flexion of light, in reply to the Rev. B. Powell, iii. 172; Rev. B. Powell's re- marks on, iii. 412; on the influence of high and low prices on the rate of mor- tality, v. 278 ; on the physical causes of the phaenomena of heat, x. 342. Barytes, carbomethylate of, xi. 143. and strontia, hydrates of, vi. 52 ; ix. 87 ; xi. 301 ; separation of, viii. 259. Baryto-calcite, dimorphism of, vi. 1 ; composition of the, x. 373; on the right rhombic, xi. 45. Basalt, of tlic Titterstone Clee Hill, i. 231. 8 (5ENERAL INDEX OF VOLS. 1 — 12 OF THE B»t, on a new genus of, iv. 300. , long-eared, habits of, viii. 265. Bate (Mr.) on an improvement in medal- ruling, ii. 288. Bath, geological table of strata in the vi- cinity of, ii. 46 ; on the gases of certain springs at, iv. 221, 225. Bats, habits and ojconomy of, vi. 388. Batten (Dr.), notice of the late, xii. 277. Baup (M.) on kinic acid and some ki- nates, ii. 479. Bayfield (Capt.), on the transportation of rocks by ice, viii. 558. Beaumont's (M. de) theory of the paral- lelism of contemporaneous lines of ele- vation, iv. 404 ; remarks on, i. H8. Beck (Dr.) on the geology of Denmark, viii. 553. Becquerc4 (M.) on the reduction of me- tals by electricity, x. 154; on an electro- magnetic balance, and on a battery with invariable currents, x. 358; on sili- ceous and calcareous products, xi. 403 ; Copley medal awarded to, xii. 348. Beke (C. T.) on the Gopher-wood of the Scriptures, iii. 103 ; on the former ex- tent of the Persian Gulf, iv. 107 ; re- ply to Mr. Carter on the Gopher-wood, iv. 280 ; reply to his papers on Gopher- wood, and former extension of Persian Gulf, v. 244; on the advance of the land in the Persian Gulf, vi. 401 ; vii. 40 ; on the Persian Gulf, and on the non-identity of Babylon and Babel, viii. 506 ; ix. 34 ; xi. 66 ; on the com- plexion of the ancient Egyptians, xi. 344. Bell (Dr.) geology of Mazunderan, xii. 57J. (Sir C.) on the functions of the brain, v. 451 ; on the spinal chord, vii. 138. (T.) on two reptiles hitherto un- described, iii. 375 ; on the neck of tlie Three-toed Sloth, iii. 376 ; description of Cyclemys, a type of a new genus of the freshwater tortoise, v. 143 ; on the genus Galictus, xii. 529. Bennett (E. T.) on the new genus La- gotis, iii. 149; on Felis viverrinus, iii. 294 ; on a peculiar species of monkey, iv. 61 ; on several rodent animals, ix. 68 ; remarks on the Indian antelope, ix. 306, 310; on the brush-tailed kan- garoo, ix. 388 ; notice of, x. 465. (F. D. ) on the anatomy of the sper- maceti whale, xi. 196. • (G.) on the habits of the King Penguin, v. 231 ; natural history and Iiabits of the Ornithorhynchus para- doxus, vi. 307; on tlie phosphorescence of the ocean, xii. 211 ; on a speciesd^ Glaucus, xi. 118. Bennetts (John) on tlie electro-magnet- ism of veins of copper-ore in Corn-wall, iii. 17. Benson (Mr.) on the importation of the living Cerithium Telescopium, vi. 70. Bentham (G.) on the genus Hosackia and the American Loti, vi. 221 ; on the Eriogonea;, vi. 379 ; on the Mora tree of British Guiana, xii. 532. Benzin, production of, xii. 460. Benzoic acid, action of iron at a high tem- perature on, xii. 460. Berbcrin, xi. 338. Berger (Dr.), notice of the late, iv. 444. Bermuda, on the carbonic acid in the at- mosphere of, xi. 225 ; meteorological observations taken at, in 1836, xi.449. Bernoulli's solution of the problem of shortest twilight, Mr. Davis on, iii. 179, 277 ; theory of the tides, vii. 457. Beroe, species of, vii. 495. Berthier (M.) on the magnetic action of manganese, ix. 65. Berzelius (Baron) on chemical formulae, remarks on, iv. 9 ; discovery of chrenic and apochrenic acids in the mineral waters of Porta, v. 238 ; preparation of pure tellurium, vii. 539 ; on the pro- perties of tellurium, viii. 84 ; symbolic notation first introduced by, viii. 101 ; on Faraday's supposed sulphate and oxide of antimony, viii. 476 ; on me- teoric stones, ix. 429 ; a Copley medal awarded to, x. 212; reply to Dr. Hare's remarks on his chemical nomenclature, xi. 179; on xanthophylle, xii. 135. Bevan (B.) on the cohesion of cements, i. 53 ; on the strength of timber, i. 116; on the difference of level between the sea and river Thames, i. 187 ; on the dimensions and value of the measures used in Covent Garden market, i. 472 j ii. 405 ; on certain defects in the Bri- tish Almanac, ii. 30; on the modulus of elasticity of gold, iii. 20 ; table of sines to centesimal parts of the versed sine, iii. 99. Bianchi (Prof.) on a new sidereal cata. logue, X. 67. Bible, on the different kinds of wood mentioned in the, ii. 412. Bibliographical Bulletin, xii. 208. Bibromide of mercury, ix. 148. Bichromate of the perchloride of chrome, xii. 83. .,j ; Biela's comet, i. 401; v. 301, 310 ; obser- vations on, ii. 222. Biniana, Quadrumana, and Pedimana, on the natural affinities which subsist between the, ix. 302. LOND. AND EUIN. PHILOSOPHICAL MAGAZINE, 1832 1838. Binks (C.) on the phnnomena and laws of action of voltaic electricity, and con- struction of voltaic batteries, xi. 68. Binney (E. W.) on a patch of red and variegated uiarls, viii. 571. Biotine and anorthite, identity of, x. 368. Birch, structure and growth of the bark of the, xii. 55. Bird ( Dr. G.),on the existence of titantic acid in Hessian crucibles, vi. 113; on certain new combinations of albumen, with an account of some curious pro- perties of that substance, ix. 109 ; x. 85; on the action of electricity on albumen, X. 357 ; on electric currents of low ten- sion, X. 376 ; on induced electric cur- rents, with a description of a magnetic contact-breaker, xii. 18; on indirect chemical analysis, xii. 229. Birds, notes on various, ix. 66, 139, 141, 142, 147,227,503,511,512,552; geo- graphical range of, vii. 418, 493 ; on the diving of aquatic, i. 23. of passage, notice of the arrival of, &c., ii, 96 ; iv. 336 ; vi. 424. Birt( W. R.), meteorological observations made during the solar eclipse of May 15, ix. 393. Bischoff (Prof.), analysis of plenakite, vii. 540. — — (J.) on the cause of the grave and acute tones of the human voice, vi. 372 ; on the physiology of the human voice, ix. 201, 269, 342. Bismuth, peroxide of, iii. 387; chlorosul- phuret of, xi. 560 ; on the peculiar vol- taic condition of, xii. 48 ; action of ni- tric acid upon, xii. 305. and iron, on the peculiar voltaic in- activity of, xi. 544. and cadmium, separation of the oxides of, vi. 235. and lead, separation of, iii. 389. Bitumens, constitution of, ix. 487. Blackburn (C.) on the modern tele- graphs, v. 24 1,365; analytical theorems relating to geometrical series, vi. 196. Blackw all (J. ) on the diving of aquatic birds, i. 23; observations on the house spider, i. 95 ; on a new species of Arachnida, i. 1 90; on someundescribed Araneidee, iii. 104, 187, 344, 436 ; v. 50 ; viii. 481 ; x. 100. Blake (J.) on the electrical currents produced during the processes of fer- mentation and vegetation, xii. 539. Blewitt (O.) on an erroneous statement respecting Mr. Faraday, iv. 261. Blood of cholera patients, researches on the, i. 295. , its circulation in insects, vi. 300; titanic acid in, vi. 201 ; influence of the tricuspid valve of the heart on the circulation of the, vii. 207; on the re- gulation of the quantity of blood with- in the heart, vii. 212 ; notice of certain appearances in, vii. 410 ; on the gases contained in the, xii. 300. Blow-pipe, a new oxy-hydrogen, i. 470. Blue colours, preparation of, vi. 156. Boase (Dr. H. S.), on the structure of rocks, vii. 376, 445 ; on Mr. Hopkins's ♦' Researches in Physical Geology," ix. 4, 10, 14; Mr. Hopkins's reply to, ix. 171, 366 ; on the composition and origin of porcelain earth, x. 348. Boddington ( B. ) on the effects of a stroke of lightning, i. 191. Bog timber, on, vii. 499. Bonaparte (C. L.) on the arrangement of the vertebrate animals, xii. 92. BonsdoHF (Dr.), on the solubility of oxide of lead in water, xi. 221. Bones of the rhinoceros and hyena in the Cefn caves, discovery of, i. 232. Bonomi (Mr.) on the ring money of Africa, xi. 132. Bonn, meeting of the Scientific Associa- tion of Germany at, vii. 157. Bonnet (G.) on the reducing powers of arsenious acid, ix. 230. Books, new, notices respecting, vii. 541 ; ix. 4; xi. 481, 548; xii. 127,202,263, 379, 536, 602. Boomarang, on the path of the, xii. 329* Booth (J.) on the conic sections, xii. 104. Boron, preparation of, x. 419. Boroughs, on a formula for the relative importance of, i. 26. Bostock ( Dr. ) analysis of a mineral water from the island of St. Paul, vi. 312. Botanical alliances, origin of the, xi. 247, classification, on the present state of, xi. 48. Botanical Society of Edinburgh, viii. 440. Botany : — deviations from the ordinary structure in Telopea speciosissima, v. 70 ; female flower and fruit of Raffle- sia, v. 70; structure of Hydnora, v. 70 ; internal structure of plants, v. 1 12, 181, 284; action of tannin on the roots of plants, v. 157 ; a newly ob- served property in plants, vi. 164 ; on the genus Hosackia and the Ame- rican Loti, vi. 221 ; on the classifica- tion of vegetables, vi. 379 ; on the Eri- ogonea;, vi. 379 ; on the species of Fe- dia, vi. 380; of the Himalayan moun- tains, vii. 132 ; on the formation of wood. vii. 498 ; notice of a yew found in a bog, vii. 499; notice of a yew at Macruss, vii. 499 ; on bog timber, vii. 499 ; Oxalis tuberosa, Solanum tube- rosum, Cevadilla, Amole, Cestrutn B 10 GENERAL INDEX OF VOLS. I 12 OF THE I AA .OWOJ Mutisii, vii. 500 ; pericarp and nuts of the Palo de Vaca, vii. 501 ; Indian GentianejB, viii. 75 ; two species of the genus Pinus, viii. 255 ; on the Ne- phrodium rigidum, viii. 255 ; varieties of Erica ciliaris and Tetralix, viii. 256 ; on several new British and European plants, viii. 345 ; on a species of Agave, viii. 346 ; Cooper's botanical rambles, viii. 411; action of light upon plants, and of plants upon the atmosphere, viii. 415; on the ovula of Santalum album, viii. 423 ; W. Sherard and Dil- lenius, viii. 424 ; Botanical Society of Edinburgh, viii. 440; on the green colour of plants, viii. 469; on germi- nation, viii. 491; ix. 17, 371, 372; classification of vegetables, x. 37, 108 ; a grass (Spartina glabra) new to the British Flora, x. 71; on the Esula major Germanica of Lobel, x. 71 ; on the tree from which the Indians prepare the poison called wooraly or ourary, x. 72 ; Aphyteia, H} dnora, and Cynomorium coccineum, x. 73 ; descriptions of two species of Coniferae, x. 73 ; notice of M. Jussieu, X. 153; descriptions of Polygonum and Fagopyrum, x. 223 ; Polygonum dumetorum and Epipactis purpurata, x. 225 ; manna of Mount Sinai, dragon's blood tree and aloe plant of Socotra, x. 226 ; on the ab- sorbent powers of the roots of trees, x. 4S8 ; on the hymenium of fungi, x. 492 ; ascent of the sap, x. 494 ; on structure in the ashes of plants, xi. 13, 413 ; on botanical classification, xi. 48, 137 ; Anatifa vitrea, of the Irish coast, xi. 135; progressof phytochemistry in reference to the physiology of plants, xi. 156; origin of botanical alliances, xi. 247 ; progress of vegetable physi- ology, xi. 381, 435, 524; botanical affinities of Orobanche, xi. 409; com- position of vegetable membrane and fibre, xi. 421 ; combination, structure, and contents of the cells of plants, xi, 435 ; Baciilariae, xi. 448 ; cow tree of South America, xi. 452; on the system of circulation in vegetables, xi. 528 ; milk vessels of the Euphorbiaceae and Asclepiadeae, xi. 529 ; internal struc- ture of the wood c f palms, xi. 553 ; on the conservation of living plants, xi. 566 ; on the structure and growth of the more perfect plants, xii. 53 ; on the stem of plants, xii. 62 ; Cucubalus bac- cifer found in the Isle of Dogs, xii. 93 ; fossil ferns, xii. 95 ; Laminaria digitata, xii. 96 ; on the genus Chara, xii. 97 ; development of the organization in phaenogamous plants, xii. 1 72, 24 1 , 292 ; " Flora of Jamaica", xii. 263; struc- ture of Cuscuta europtea, xii. 531 ; on the mosses of Upper Assam, xii. 532; Mora tree of Guiana, xii. 532 ; exist- ence of stomata in mosses, xii. 533. Bottinger (M.) on the colours of metafe, xii. 298. Botto(Prof.) on the chemical actionieif magneto-electric currents, i. 441, > an Bou6 (Dr.) notice of his " Guide^dn Geologque Voyageur", vii. 541, .■;'>■>•< Boulderstone, on a large one in Argyle- shire, i. 232. Boussingault (M.) on suboxide of lead and protoxide of tin, v. 79 ; on the sup- posed compound of hydrogen and pla- tina,v. 155. ;;; i Bowerbank (J. S.) account of » deposit containing land-shells, at Gore Cliff, Isle of Wight, xi. 103. Braconnot ( M.) on isomeric modification of tartaric acid, i. 83. : lr;i Brain of the negro, on the, ix; 527i v«l , analysis of the, v.: 892;ioh<]t&& functions of the, v. 451;f' ; o. 'A'nuan ., human, x.286 ; on the accumula- tion of fluid in the, x. 316; in marsu- pial animals, x. 222. Branch, on the structure of the, ii. 120. Brande (Mr.) on chemical notation, ii. 309 :..nia..fu \-. :,,!„■,., ... .. ,.,.,;irK Brayley (EwAWofi^l) sola tihejiistoryiiof certain suggestions reispecting the dark spaces in the solar spectrum, ix. 522, note ; on M. Lenz's paper on the con- ducting power of wires for electricity, xi. 11, note; letter to, from Mr. Fara- day, on some former researches on the peculiar voltaic condition of iron, ix. 122; on the history of certain points in magneto-electricity, ix. 237, note; on the origin of certain sounds, iii. 329, note ; note on Prof. Challis's paper on capillary attraction, viii. 172; re- marks on by Prof. Challis, viii. 289 ; on the history of our knowledge of the oscillation of the centre of gravity of Saturn's rings round that of the body of the planet, iii. 129 ; on the appear- ance of birds when seen in telescopic observations on the sun, i. 333, note ; on the importance of comparative ana- lyses of the allantoic fluid and the urine of the young animal after birth, i. 322 ; on the true source of the amnio- tic acid of Vauquelin (allantoic acid of Lassaigne), i. 319 ; on the supposed amalgam of mercury with a metallic substance (ammonium) derived from ammonia or its elements, vi. 217; on the relations of iodine to the conduc- tion of heat, vii. 441, note; viii. 130, LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. U fM^ei^ on'tlie black precipitate of pla- tinum, and on platinum powder, vi. 362, 363, notes ; on the discovery of silicuret of platinum, i. 267, note; on the protection of steel from the action of the atmosphere by zinc, vii. 392, note ; on the nature of a fluid obtained in the manufacture of pyroxylic spirit, as described by Mr. Scanlan, vii. 396, note ; table of high temperatures cor- rected from Prof. Daniell's pyrometri- eal researclies, vi. 249 ; see xii. 535, note ; letter to, from M r. l^rideaux, on the dew- point, on the detection of foreign mat- ters in the atmosphere, xi. 54 ; his re- vised edition of •' Parkes's Chemical Catechism," review of, vi. 214 ; on the orijjrin of the diamond, iii. 220, no/e; on hydrocarbonate of lime, 'iii. 86, note ; v. 1 96, 1 97, notes ; on the formation of Entophyta in the vomicae and bron- chial tubes of a Flamingo, as described by Mr. Owen, ii. llynote; discrimina- tion between the two Javanese poisons usually confounded together under the name of Upas, vi, 218; remarks on Sir E. F. Bromhead's paper on bota- nical classification, xi, 137,253, note; proposal to employ the word affinal in natural history, v. 206, mUe ; on the affinal connexion of mammalia with birds through the Ornithorynchus,&c., as indicated by the structure of tlie cry- stalline lens, iii, 447, note ; notice of a memoir on the natural laws which ap- pear to regulate the distribution of the powers of producing heat and light among the different groups of the ani- mal kingdom, vi. 241; on the natural history of the Papuans, or Asiatic ne- groes, i. 466 ; on the tendency to a cir- cular succession of affinities in the group of Simite, vi. 462, 7iote ; on the frequent deficiency of the ungueal pha- lanx in the hallux of the orang ou- tang, vii. 72 ; on the maneless lion, iv. 379, note ; on a gigantic carp, xi. 223 ; on tlie silent flight of Musca vomitoria, X. 827 ; on the relation between the extinct and living animals confined to America, xi. 208, note ; ontlie equiva- lent, in the Danish island of Seeland, of the coralline crag of England, vii. 413, note; on the denudation of val- leys, i. 339, note ; on the agency of heat in the consolidation of the new Ted sandstone, vii. 515, note; on the porphyritic amygdaloid of Devonshire, xii. 568, note ; on the theory of rolca- Tios, xii. 533, 588, note ; on the state of knowledge and theory on the al- leged periodical meteors, xi. 273 ; on the fall of meteorites at Magdeburg in the year 998, iii. 454, note ; review of the Report of the First and Second Meetings of the British Association, ii. 455 ; iii. 1 29 ; of Mr. Conybeare's Report on Geology, iv. 427 ; of Mr. Lubbock's Mathematical Tracts, iv. 218; of Abstracts of Papers printed in the Philosophical Transactions, iv. 47 ; of the West of England Journal of Science and Literature, vi. 293. Breath, on holding it for a lengthened period, iii. 241. Breccia and iodine, xi. 216. , hydriodate of, xi. 216; iodate of, xi. 217. Breithaupt's Mineralogy, notice of, v. 237 ; viii. 173. Brett (R. H.) on the existence of titanic acid in Hessian crucibles, vi. 113 ; on the solvent action of muriate and ni- trate of ammonia, x. 95, 333 ; on the bromo-cyanide and chloro-cyanide of potassium and mercury, xi. 340 ; ana- lysis of some double salts of mercurj^ xii. 235. .; Brewster (Sir D.) on M. Rudberg's me- moir on crystals, i. 6, 146, 415; on a new species of coloured fringes, i, 19; on the effect of compression and dilata- tion on the retina, i. 89; letter to, from M. KuptFer, on inagnetical discove- ries, i. 129; on magneiical and meteor- ological observations made at Pekin, i. 130 ; on his formula for mean tempe- rature, i. 155 ; on undulations excited in the retina, i. 169; notes on Prof. Kupf- fer's observations on the temperature of Nicolaieff and Sevastopol, i. 135, 260; letter to from Prof. Necker, on certain optical phaenomena seen in Switzer- land and on viewing the figure of a geo- metrical solid, i. 329 ; on the action of heat on glauberite, i. 417 ; observa- tions on the isothermal lines, i.431 ; on a Chinese mirror, i. 438 ; on the mean temperature of Irkoutsk, ii. 3 ; Prof. Airy on his experiments on the polari- zation of light by the diamond, ii. 29 ; letter to from Mr. Forbes on Fourier's demonstrations relative to the mathe- matical law of heat, ii. 103; on a singu- lar fog-bow, ii. 151 ; on the action of light on the retina, ii. 168; on the un- dulatory theory of light, ii. 360; Prof. Airy's answer to, ii. 419; on the dia- mond, iii. 219; on certain changes of colour in the choroid coat of the eye, iii. 289; reply to by G. II. Fielding, iv. 14; on the crystalline lens, iii. 446 ; on Mrs. Griffiths's paper on the vision of the retina, iv. 46 ; on the blood- ves- B2 12 GENERAL INDEX OF VOLS. 1 V2 OF THE Ol sels of the eye, iv. 115; award of the royal medal to, iv. 133 ; on the influ- ence of successive impulses of light on the retina, iv. 241 ; on a rhombohe- dral crystallization of ice, iv. 245; on accidental colours, iv. 853 ; notice of the optical properties of a new mi- neral, vi. 133; on the achromatism of the eye, vi. 161 ; Prof. Powell in reply to, vi. 247 ; on peculiarities in the double refraction and absorption of light, exhibited in the oxalate of chro- mium and potash, vi. 305; vii. 436 ; on the structure and origin of the dia- mond, vii. 245 ; on the crystalline lenses of animals, viii. 195, 416; on the lines of the solarspectrum,andon those produced by the earth's atmosphere, and by the action of nitrous acid gas, viii. 384 ; on the colours of natural bo- dies, viii. 468 ; on the optical property of a substance resembling shell, viii. 545; examination of, x. 201; on the optical properties of chabasie, ix. 1 70 ; X. 201 ; on the connection between the phaenomena of the absorption of light and the colours of thin plates, xi. 95 ; on the crystalline lenses of animals af- ter death, xi. 97 ; on a singular deve- lopment of polarization in the crystal- line lens after death, and on cataract, xii. 22; on Von Wrede's theory of the absorption of light, xii. 115; on an op- tical phaenomenon seen in the Gram- pians, and on Poisson's theory of the atmosphere, xii. 123; on the colours of mixed plates, xii. 355. Bridges, skew, construction of, viii. 299 ; oblique, x. 74, 167. Brinkley (Dr.), notice of, viii. 155. British almanac, on defects in the, ii. 30. British Association, ii. 319 ; Reports of of the meetings of, ii. 455; iii. 151 ; iv. 319; xii. I 10; proceedings at Edin- burgh, V. 386 ; suggestions respecting the ensuing meeting, vii. 118; Dublin meeting, vii. 71, 237, 289, 385, 480; viii. 53; ix, 228, 312; list of the Coun- cil appointed at Bristol, ix. 312; re- ports undertaken for the next meeting, ix. 312; grants for the advancement of particular branches of science, ix. 312; meeting at Liverpool, xi. 396, 474,551. Broderip (W. J.), descriptions of new species of Calyptraeidae, v. 72, 232 ; de- scription of a new genus of Gastero- poda, V. 312; on Clavagella, vi. 381 ; on the habits of the Chimpanzee of the Zoological Gardens, viii. 164; on the . genus Mitra, Lam., ix. 136. ^ > Bromhead (Sir E. F.) on the present state of botanical classification, xi. 48 ; remarks on his paper on botanical classification, xi. 137 ; on the origin of the botanical alliances, xi. 247. Bromine, proportion of, in the waters of different seas, vi. 321 ; on its conduct- ing power for electricity, viii. 130,400; new acid of, viii. 588 ; preparation of, X. 499 ; its action upon^ «eth^ ix. 149. ... . . . ■ rn ..v/'f ::vud}wt Bromo-cyanlde of potassium and m6if- cury, xi. 340. Brooke (H. J.), mineralogical notices on symbolic notation, viii. 101 ; on thulite and stromite, viii. 169; on the crystal- lographical identity of certain mine- rals, X. 170; on the intersection of cry- stalline minerals, x. 278 ; on the iden- tity of phacolite and levyne with cha- basie, xi. 12 ; on murio-carbonate and muriate of lead, xi. 175; on the cry- stalline form of pyrosmalite, xi. 261 ; on an apparent case of isomorphous substitution, xii. 406. ' Broughton (J. D.), notice of, xii. 278. Brown (R.) on the impregnation of the Orchideae and Asclepiadese, i. 70; on the structure, &c. of Cephalotus, i. 3 1 4 ; on the new genus Limnanthes, iii. 70; on the female flower and fruit of Raf- flesia, v. 70. Bruit de Soufflet, mechanism of, vii. 508. Bryce (J;) list of the simple minerals of the North of Ireland, iii. 83; v, 196. Buckland (Rev. Dr.) on the structure of the sloth, ii. 308 ; notice of a newly discovered gigantic reptile, vii. 327 ; on the fossil beaks of four extinct spe- cies of Chimsera, viii. 4 ; on silicified trunks of trees in the new red sand- stone, x. 475; " Bridgewater Treatise," X. 410; on the keuper sandstone in the upper region of the new red sand- stone formation, xi. 106. .l-'^> Bud, structure of the, ii. 125.> nohrruiD Buenos Ayres, on the discovery of three skeletons of the Megatherium in the province of, i. 233. Bulbs, on the structure of, ii. 124. Bulletin, bibliographical, xi. 481, 548. Bunt (T.G.) on anew tide-gauge, xii.430, Burnes (Lieut.) on the geology of the Indus, iv. 225. Burning cliffs, on the south-cast coast of Newcastle in Australia, i. 92. - Burr ( F.), geology of the line of the Bir- mingham and Gloucester railway, xii. Bussy (M.) onthepreparatioilidf iodiner, X. 498; preparation of bromine, x. 499. Butler's ( Dr.) theory of the action of the LOND. ANDTEDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 13 siphuncle id the pearly Nautilus, xli. 503. Buzareingues on the distribution and mo- r. ^e0.<>f tfae^ap in plants, xi. 526. CJ, on Fresnel's theory of double • refraction, x. 24. C. S. on Whiston, Halley, and the Quar- noitierly Reviewer of the " Account of Flamsteed," viii. 225. Cabiric rnysteries in India, xii. 110. Cadmium and bismuth, separation of the oxides of, vi. 235. Caff'ein, composition of, i. 165 ; ii. 404. Calamary, eye of the, viii. 1. Calc spar, formation of, xii. 465. Calcareous spar, artificial, ix. 230. Calculi, composed of cystic oxide, xii. SS7 ; urinary, collection of, in St. Bar- tholomew's Hospital, xii. 412. Calculus, new renal, viii. 446. Caldcleugh (A.) on the earthquake in Chili, Feb. 20, 1835, viii. 148; volca- nic eruption of Coseguina, viii. 414; on the elevation of the strata on the coast of Chili, xi. 98. Callan ( Rev. N. J.) on a new galvanic battery, ix. 472 ; reply to Dr. Ritchie, X. 459. Caloric, electricity, and ponderable bo- . ..dies, remarkable analogy between, v. 110. , M£!4cloirific effect of the sun's direct rays, Tto c*iit.'lj&2tv. -;...:.' -.■ •7r>e^rays^©n*iviit23.109i 186, 190, 248; ] their transtnission through diathermal bodies, vii. 475. Calyptrjcidae, anatomy of, v. 72; new . species of, v. 72, 232. Calyx and corolla, on the, ii. 126. Cambridge Philosophical Society, pro- . ceedings of, ii. 314, 380; iii. 235, 461 ; r.i 'ir. 66, 312, 463; vi. 73, S95; vii. 70; -bfHSui. 78,429; ix. 71 ; x. 316, 485; xii. 452. Camden Literary and Philosophical In- ...Stitution, viii. 431. Camphor, analysis of, ii. 153 ; rotary motion of, v. 152 ; aitificial, viii. 588 ; experiments on, x. 420 ; action of iron at a high temperature on, xii. 460. Camphoric, acid, xii. 297 ; iuihydrous, xi. .i,t22-l.; . oy^ -yv, n. aether, xi. 221. Camphovinic acid, xi. 221. . . ..no. i Cantharidine, preparation ofi.vi* 3 llL ! Caoutchouc, on, ii. 77 ; volatile liquid from, ix. 321, 479. Cape Farewell, geographical position of, vii. 490. Oape Observatory, latitude and longitude Capillary attraction, viii. 89, 172, 288. Carbohydrogen, nitrate of, viii. 85 ; new combinations of, ix. 77. Carbomethylate of barytes, xi. 143. Carbonate of lime, formation of, under the influence of sugar, i. 84 ; solubility of in hydrochlorate of ammonia, ix. 540 ; decomposition of by heat, x. 496 ; occurrence of on Saxifrage leaves, xi. 445 ; crystalline form of, xii. 465, 470. of strontia discovered in the United States, vi. 234. Carbonates, earthy, and alkaline nitrates, analogy in atomic constitution between, xii. 4»0. Carbonic acid, solidification of, viii. 446 ; liquid, viii. 583 ; solid, degree of cold produced by, x. 158 ; in the atmo- sphere, on the, xi. 226. " and ammonia, on the combi- nations of, iii. 457. oxide, on Prof. Mitchell's method of preparing, vi. 232. Carboniferous series of North America, on the, ix. 124, 407. Carbovinate of potash, xi. 320. Carlisle's (Sir A.) letter, with the reports on the health of the workmen clean- sing the Westminster sewers, i. 354. Carmine, analysis of, iii. 381 ; adultera- tion of, xii. 462. Carp, gigantic, xi. 223. Carter (W. G.) on the Gopher- wood of Scripture, iv. 178; reply to, iv. 280; on the former extension of the Persian Gulf, V. 244; vii. 192, 250. Cask-gauging, on, iv. 326. Cast iron, cohesion of, iii. 79. beams, Mr. Hodgkiuson on, viii. 65. Catalysis, a new force acting in the com- binations of organic compounds, x. 490. Catania, new observatory at, viii. 256. Cataract, on, xii. 25. Cathedrals, destruction of painted glass in, ix. 458. Cathedral choirs, neglect and decay of, ix. 458. Cations, v. 429. Cauchy's (M.) researches on light, iv. 396; view of the undulatory theory of light. Prof. Powell's abstract of, vi. 16, 107, 189, 262 ; theory of double refraction, viii, 104: undulatory the- ory of light, viii. 7, 24, 112, 204, 247, 217, 305, 413; new formula for sol- ving the problem of interpolation, viii. 459. Giustic potash, preparation of, i. 244. Caustics, equations of, vi. 372. Cautley (Capt.) on the remains of mam- 145 GENERAL INDEX OF VOLS. 1 12 OF THE malia found in the Sewalik mountains, viii. 57.5 ; xi. 20S ; on tlie Sivatlierium giganteum, ix. 193; on a fossil mon- key from tlie tertiary strata of the Se- walik hills, xi. 393. Caves of Cefn in Denbighshire, on the, i. 232. Cavy, new species of, ix. 69. Cellular membrane, composition of, xi. 440. Cements, on the cohesion of, i. 53. Cephalopoda, new or rare, ix. 298. Cephalotus, on the structure and affini- ties of, i.314. Cervus, new species of, ix. 391 ; nemarks on the genus, ix. 518. ' Cetacea, mammary glands in the, vii. 507. Cetrarin, on, xii. 296". Chabasie, optical properties of,, ix. 166, 170; identity of phacolite and levyne with, xi. 12. Challis (Rev. J.) on the resistance to the motion of small spherical bodies in elastic mediums, i. 40; on Lagrange's proof of the principle of virtual veloci- ties, ii. 16; on the theory of the ball- pendulum, iii. 185; on the brachysto- chronous course of a ship, iv. 3S ; ana- lytical determination of the laws of transmitted motion, vi. 267 ; on the vibrations of a cylindrical tube, vii. 300; on capillary attraction and the molecular forces of fluids, viii. 89 ; on the phaenomena of drops of oil floating on water, viii. ii88. Chama, on some species of, vii. 65. Chamctleon, new species of, iv. 150. Chamouni, on the relative position of, with respect to the convent of St. Ber- nard, ii. 61. Chara, influence of heat, &c., on theioteO culation of the, xii. 457. Charcoal, on its ignition in atmospheric temperatures, iii. 1 ; cause of the spon- taneous combustion of, iii. 89. Charlesworth (E.) on veins of crystal- lized carbonate of lime in fossil wood, vii. 76 ; on the crag-formation and its organic remains, vii. 81 ; viii. 529; on the coralline crag, in reply to Mr. Woodward, vii. 464 ; on the relative age of tertiary deposits, x. 1. : i • Charnwood forest, on the geology^ofj iv. 68. Cheiropoda, proposed name for all mam- mals possessed of hands, ix. 306. Chelostoma florisomnis, xii. 18. Cheltenham, mineral waters of, i. 223. Chemical action, modes for examining under the microscope the phaenomena of, ix. 10. , » — — analysis, indirect, xiii 229. Chemical electricity, ix. 53.-1. t.,!(jPoiollri^ flames, on the spectra of, rii .Sintn preparations, English, on the-fodQ quent presence of lead in, viii. 267 J"; philosophy and nomenclature, on certain points of, xi. 176. ' i science, grants of money for the ad^ vancement of, ix. 314. symbols on the use of. Hi. 443. Chemistry, on a perfect system of sym- bols in, i. 181 ; on the use of symbols- in, iv. 41, 106, 246, 402, 464. i of geology, on the, iii. 20. o — I — , microscopic, on, ix. 2, 10. i«r!!'' , organic, researches in, x. 45, 116. and mineralogy, section of, xi.554. Cheverton ( Mr.) oa. iBdcbanical iscut^- ture, viii. 70;- m.- ip.-\h-:ryi\ia :■ i'jRci Chichester, earthquakes at, vii. 208.' '.'0. Children (J.G.), on Dr. Ehrenberg'sodklO lection of dried Infusoria and raiet«(>- scopic objects, ix. 90. ';•;';] ouiniriCs Chili, earthquake of, Feb. l20,<483iSi ^«i.-- 74, 148 ; elevation of strata-.tth.tihe coast of, xi. 98, 100. '"-m 'Tujlr Chimaera, on the fossil beaks of, viiii!^ Chimpanzee, habits of the, viii. 161 ; diftl> section of the, ix.388. . .i;;i China, a curious mirror brought frotrt^^. 438. ■ ! -:=?io Chironectes Yapock, Desm., ix; 610.''ft0 Chloral, a new compound analogous tMp, X. 321. ^o Chloride of soda, its use in fever, viii. 64. of tungsten, xii, 461. '- w of calcium, compound «flfwill*wt> roxylic spirit, x. 47. -t^^ :j.(i irt Chlorides, metallic compounds of, with chromic acid, iii. 235 ; action of feul- i phuric acid on, x. 157 ; their detection I in bromides and iodides, xii. 136. Chlorine, extemporaneous solution of, i. 85 ; on an unobserved property of, iii. 72; action of, on metallic iodides^ iv. 467 ; on its conducting power for elec- tricity, viii. 130, 400; action of, on pyroxylic spirit, x. 49 ; decolorizing combinations of, x. 155; action of, on gum, ii.405 ; new compounds of, xii. 220; action of, on aethers, xii. 297. Chlorocarbonic acid, iv. 385. Chloro-cyanide of potassium and mercury, xi. 342; of ammonium and mercury, analysis of, xii. 236 ; of sodium and mercury, analysis of, xii. 237 ; of cal- cium and mercury, xii. 238 ; of barium and mercury, analysis of, xii. 939 j of magnesium and mercury, analysis of, xii. 239 ; of strontium and mercury ,- analysis of, xii. 240, ' Chloroform and cyarioform, on^ xlv^3S9i ' Chlofophylle, analysis of, iii. 381^i 'M'i'U) LOND. AND EDIN; PHILOSOPHICAL MAGAZINE, 1832 — 1838. 15 Chlorosulphurcts of l^ad, copper, bis- muth, and zinc, xi. 5G0. Cholera, on the health of the workmen cleansing the sowers during, i. S54. patients, chemical researches on the blood of, i. 295. - '> . , -j Chorion, mode of the origio>ofvtb^:. :..■:, Chrenic acid in ^4^ >niin€)ral'>w«ter9-of^ Porta, V. 2fJ8. f '' • - ij Christie (Dr. A. T.), notice of, iv. 445, Christie (C. C) on the aurora borcalis of Nov. 18, 1835, viii. 412. Christie (S. H.) on the laws of magneto- electric induction, iii. 141 ; on terres- trial magnetism, iii. 215; Bakerian lecture, remarks on, iv. 208; on Capt. Back's magnetrcal observation^-] Jk. 523, 529. : ■ .. .^yfbi-.':) Cbromate o£^Jctdd^( dimorphism oi^loiadi) . S87. ■■i.r. i;iiO?.i\'\ii' iwi.t;)')! Chrome, preparation of metallic, i. 86. — I — ; bichromate of the perchloride of, xii. 83. alum, newmcthod of obtaining, xii. 218. Chromic acid, compounds of, with rae- tiUic chlorides, iii. 235 ; its action upon silver, and combinations with the oxide of silver, xi. 489. Chromium, oxalate of, and potash, optical properties of, vii. 436; crystallized oxide of, viii. 175 ; iodide of, viii. 192 ; Jteriodide of, xii. 321 ; combinations of, with fluorine and chlorine, ix. 151. Chronometers, ^lass a substitute for me- tal balance-springs in, ix. 381. Cinchonia, iodate of, xi. 217 ; elementary composition of, xi. 335. Cinnamon, oil of, vii. 74. Circulating organs in diving animals, vii. 502. ,' : Circulation , of the blood, on the, vii. 207. Cirripedes, metamorphosis of the, vi. 573. Citric rether, analysis of, xi. 139. acid, constitution of, xii. 381. Clark (Dr.) pn cyanide of potassiutOtoV. B29; - ',<;■:.' ■ -<'.r nr Clarke (E. M.) onanfew phsenomenooi in magneto-electricity, vi. 169; on certain optical effects of th« magneto-electri- cal machine, vi. 427 ; apparatus for the decomposition of water, vi. 428; effects of voltaic magnetism on iron, vii. 422 ; description of his magnetic electrical machine, ix. 262 ; rqpljftp Mc* SaiOQii, X. 455. , , , .. 'CU !ih;; ... f Mr..l . (Kev. \V. B.) on the geology, of Suftblk, xi. 106; xii. 512 ; on the geo- logical structure of tlie Cotentin, and of the vicinity of QherlMHirg^ xL 107 ; on the peat bogs and submarine forests of Bourne Mouth Valley, xii. 579. Classification, principles of, vii. 491. Clavagella, description of, vi. 230, 381. Clemson (T. G.) on avein of bituminous coal in Cuba, x. 161. Clinometer, Henslow's, improvement in, V. 159. Clocks, on the use of, at sea, instead of chronometers, ii. 157. ClosteriBB, mode of increase of, xi. 386; formation of the fruit in the, xi. 388. Cloves, analysis of oil of, iv. 313. Coal, observations, on, ii. 302; on the nature of, iii. 245. , in Coalbrook Dale, ix. 383; at Dudley and Wolverhampton, ix. 383 ; in the United States, ix. 124; on the coast of Cumberland, ix. 501 ; on the lower series of, in Yorkshire, i. 349. , bituminous, of Cuba, x. 161. , deposits of England, xii. 127. fields, on the future extension of in England, iv. 161, 346; v. 44; depo- sits beneath, iv. 370. —— gas, phaenomena of flame from, vii. 404. measures and fossil fruits in Lei- cestershire, iii. 76, 112. tracts, in Salop, Worcestershire, and N. Gloucestershire, vi. 376. Coalbrook Dale, geology of, ix. 382. Cobalt blue colours, vi. 157. and nickel incapable of being ren- dered inactive, xi. 547. Cocoa-nut palm, crystallized sugar from the juice of, x. 77. Cod, crystalline lens of the, viii. 193. Codeia and iodine, xi. 220. and morphia, double salt of, xi. 405. Cohesion of cements, on the, i. 53. Cold, produced by solid carbonic acid, X. 158. — -, its effects on the body, viii. 59. Colebrook (Lieut- Col.) on making cry- stallized sugar from the juice of the co- coa-nut palm, X. 77. Colebrooke (H. T.)y^iiotiee of die late, xii. 272, 438. -iiv ,-i,.i,i - .n.,v Coleopterous insects, iii. 151. Collimator, Amici's, x. 234. Collision and impact, on, viii. 65, Colombia, meteorological observations made in, between 1820, 1830, xii. 148. Colour, dependent on molecular arrange- ment, ix* 2 ; changes of, in iodide of mercury, ix. 2 ; on chemical changes ': of, ii 359. ■- and odours, influence of heat on, iii. 458. Coloured bands, in Newton's rings, vii. 363, 474. 16 GENERAL INDEX OF VOLS. 1 V2 OF THE Colouring matter of leaves in autumn, xii. 135. Colours of metals, xii. 298 ; of mixed plates, xii. ^55; of thin plates, xi. 95 ; mode of exhibiting, xii. 28 ; of natural bodies, viii. 46S ; experiments on ac- cidental, iv. 353. Colvin (Major) on the discovery of a head of the Sivatherium, xi. 208. Combinations, organic, theory of, xi. 564. Combustion of charcoal, spontaneous, iii. 89 ; on a new law of, iv. 440. Comet, Biela's, i. 401 ; Encke's and Gambart's, i. 287 ; observations on Biela's, ii. 22; vi. 45; Biela's, v. 301, 310; Encke's, v. 304; Halley's, V. 284; vii. 139, 236; viii. 148, 173; ix. 292 ; on the return of, vi. 45 ; ephemeris of, ix. 296 ; Denmark royal medal for coraetary discoveries, ix. 291. Comets, catalogue of, ii. 194, 282, 453 ; iii. 101, 198; iv. 29, 205, 349; vii. 36 ; at Paramata, vii. 69 ; Prof. Encke on Olbers's method of determining the orbits of, vii. 7, 123, 203, 280. Compass, steering, viii. 71. needles, improved, vi. 238. Conchology, ix. 32, 136, 224, 244, 350, 390,498. Condensing tube of Liebig, xi. 57. Conic sections, on, xii. 104. Conical refraction, iii. 114, 197. Coniferae, structure of, vii, 496 ; descrip- tions of two species of, x. 73. Conilurus, a new species of Australian rodent, xii. 96. Connel (A.) analysis of levyne, v. 40; analysis of fossil scales, vii. 396 ; on the action of voltaic electricity on iodic acid, X. 93 ; analysis of gadolinite, xi. 143 ; on the nature of lampic acid, xi. 512. Conybeare (Rev. W. D.) on M. De Beaumont's theory of the parallelism of contemporaneous lines of elevation, i. 118; iv. 404; on an alleged disico- very of coal in Leicestershire, iii. 112; early anticipation of phrenology, iii. 308 ; on the mountain chains of Eu- rope and Asia, iv. 1 ; fossil remains found near Edinburgh, iv. 77 ; future extension of the English coal-fields, iv. 1^1,346; v. 44; report on geologi- cal science, iv. 427. Cooper's (D.) "Flora Metropolitana," viii. 411; on the luminosity of the hu- man subject after death, xii. 420. — — , (E.J.) on Halley's comet, viii. 148. , (J. T. ) on the colouring matter of the ruby glass, xi. 137. , (P.) on the colorific rays of white light, V. 453 ; on the theory of sound, vii. 21 1 ; on the theory of the tides, vii. 212; on molecular action, x. 355. Coordinates, relative signs of, ix. 249. Copley medals, awarded to Baron Berze- lius and F. Kiernan, Esq., x. 212. Copper, blue arscniate, analysis of, iv. 237 ; fusion and appearance of, vi. 324; its immersion in muriatic acid, vi. 446 ; chlorosulphuret of, xi. 560. , arsenical, xii. 217. , antimonial, ix. 149; acetate of, ix. 395 ; sulphates of copper and iron, ac- tion of oxalic acid on, ix. 155. , protoxide of, action of protoxide of iron on, xii. 299. — — and iron, alloys of, vi. 81. Coral, new genus of, vii. 330 ; on a spe- cies of, vii. 409. Cork, on the formation of, xii. 54. Cornwall, steam engines of, x. 20, 67, 136 ; geology of, ix. 7. , Royal Geological Society of, xi. 478. Corrigan (Dr.) on the mechanism of the * Bruit de Soufflet,' vii. 508. Corrosion of metals by sea-water, on, vii. 389. Cotentin, on the geological structure of the northern part of the, xi. 107. Cotteswold hills, geology of, i. 221. Cotton, on the fibres of, vi. 170, 231. Coumarine, composition of, xi. 162. Cow tree of South America, xi. 452, 530. Cowries, hitherto undescribed, ix. 1 38. Crabro spinipectus, xii. 15. Crag formation, vii. 81, 353, 463, 464; viii. 38, 138, 529. Craig (Rev. E.) on microscopic chemis- try, ix. 10. Cranchia scabra, Leach, ix. 298. Cranes, on crowned, iv. 298. Cratomus megacephalus, xii. 14. Crichton (Sir A.), on fossil remains, viii. 574. Crook ( Dr. W. H.) on the unity of the coal deposits of England, xii. 127. Crosse (A.) on the pr<»duction of arti- ficial crystals and minerals, ix. 229. Crustacea, metamorphoses of, vii. 210; fossil, vii. 517 ; development of, xi. 552. Crystal, on an apparent change of posi- tion in a drawing of a, i. 337. Crystalline form of Kupferbluthe, vii. 159 ; of carbonate of lime, xii. 465, 470. lens, on the, iii. 5, 446 ; on a sin- gular development of polarization in the, xii. 22. minerals, intersection of, x. 278, LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 — 1838. 17 Crystalline reflexion and refraction, on the laws of, x. 42; xi. 134. — — solid, formed during the manufac- ture of sulphuric acid, iii. 1 15. structure, on, xii. 145. Crystallization, remarkable changes in the character of, ix. 13; on the water of crystallization of soda-alum, ix. 26. — — of kalium, v. 399. Crystallized iron pyrites, artificial, x. 158. surfaces, reflexion from, viii. 103. Crystals : — refraction of the coloured rays in, i. 1, 13G; on (he effects of temperature on the double refraction of, i. 410; on the phenomena of light in passing along the axes of biaxal, ii. 207; of snow, remarkable, v, 318 ; on the reflexion and refraction at the sur- face of, vii. 295 ; of the hydrates of barytes and strontia, xii, 52 ; on the optical theory of crystals, xi. 461, 537; ,xii. 73, 259, 341; occurrence of, in plants, xi. 443. -^ — , artificial, on, ix. 229, 537; x. 171 ; optical pha^nomena of, ix. 288; x. 218. Cuba, bituminous coal of, x. 161 ; on the geology of Holguin in, xi. 17; coral rock of, xi. 31. Cuckoo, remarks on the, v. 149; notice of the, X. .305. Cucubalus baccifcr, xii. 93. Culehrite, viii. 261. Cumberland, geological formation of the mountains of, i. 229 ; coal-fields of, ix. 501. Cuming (Mr.) on new species of shells from South America, vi. 68, 387 ; vii. 153, 226, 227; ix. 136 ; on the eartli- quake of Valparaiso, Nov. 1822, viii. 159. Cunningham (A.) on the physical and geological structure of the country to the west of the Dividing Range be- tween Hunter's River and Moreton Bay, New South Wales, vi. 146. ( P. ) on tlie attractions of positive and negative electric currents, viii. 550. — — (J.) on an improved mode of con- structing magnets, xi. 196. Curtis (J.) on some nondescript species of May-flies of anglers, iv. 120, 212; on a new genus of the family Melo- lonthidas, vii. 224 ; on a moth found iu the galls of a plant, vii. 224 ; *• Guide to an Arrangement of British Insects," xii. 202. Cusconin, preparation of, xi. 335. Cuscuta europaea, structure of, xii. 531. Cusparia, from Anguuura bark, iv. 154. Cutch, on the geologj of, xi. 107. J Cuvier (Baron), notice of, ii. 141 j logium on, ii. 469. "^ Cuvier (M. F.) on the Jerboas and Ger- billas, xi. 394. '• Cyanide of silver, hydrocyanic acid of uniform strength from, vi. 102. of potassium, as produced in hot- blast furnaces, x. 329. Cyanoform and chloroform, on, x. 322. Cyanogen, xii. 339 ; compound of, viii. 191 ; new radical analogous to, v. 78. Cyanuret of mercury, its decomposition by iron, vii. 78. Cyanurets, on certain metallic, iv. 91. Cynictis, a new genus of Carnivora, iii. 67. Cystic oxide, on calculi composed of, xii. 337. DJEDALEUM, properties of the, iv. 36. Dalmahoy (J.) on the greater calorific efliect of the sun's direct rays in high than in low latitudes, vii. 182. Dalton (Dr.) on ceruin liquids obtained from caoutchouc, ix. 479 ; on the con- stitution of the atmosphere, xi. 195; on the sulphuretsof lime, xi. 195; xii. 158, 397; notice relative to the theory of the winds, xi. 390. Dana (Dr.) on the manufacture of sul- phuric acid, iii. 115. Daniell (G.) on the habits of bats, vi. 388. — — ( Prof. ) on a new register-pyrometer, i. 197, 261 ; observations on voltaic combinations, xi. 89; viii. 421 ; ix. 376; xii. 364 ; on the water-barometer of the Royal Society, i. 387 ; on a new oxy- hydrogen jet, ii. 57; Copley medal awarded to, xii. 350. Darwin (F.), geological notes made du- ring a survey of the east and west coasts of South America, viii. 156. (C), on proofs of recent elevation on the coast of Chili, xi. 100; on the deposits containing Mammalia in the neighbourhooci of the Plata, xi. 206 ; on areas of elevation and subsidence in the Pacific and Indian oceans, xi. 307 ; on the formation of mould, xii. 89; on tlie geology of South America, xii. 516 ; on tlie connexion of certain vol- canic phajnomena, xii, 584. Daturia, iii. 464. Dau (Dr. Luigi) on the practicability of a nortJi-west Arctic passage, xi. 194; on the velocity of the wind, xi. 194. Daubeny (Prof.) on the strength of salt springs, iv. 31 ; on certain phasnomena ,in vegetation, iv. 52; on the gases disengaged from certain springs in ^^atli, iv. 221, ^5 ; on Dr. Ure's me- moir on the Moira brine «pring, and on C 18 GENERAL INDEX OF VOLS. I — 12 OF THE the proportion of bromine in the waters of different seas, vi. 321 ; account of the eruption of Vesuvius in 1834, vi. 374; on discoveries in volcanic strata, vii. 316 ; on the volatilization of mag- nesia by heat, vii. 406 ; on the action of light on plants, vii. 496 ; viii. 415 ; analysis of a mineral spring near Ox- ford, vii. 518; circular to men of sci- ence relative to mineral waters, vii. 541 ; on Sir H. Davy's theory of vol- canos, in reply to Dr. Davy, viii. 249 ; on tlie action of plants upon the at- mosphere, viii. 415. Davidson (J.), notice of, xii. 279. Davidsonite, a new metal in, ix. 156, 256. Davies (J.) on the spontaneous combus- tion of charcoal, iii. 89. — — (T. S.) on Bernoulli's solution of the problem of shortest twilight, iii. 179, 277 ; researches in spherical geo- metry, iii. 366 ; on the employment of coordinates, &c. in the determination of spherical loci, iii. 379 ; geometrical researches concerning terrestrial mag- netism, vi. 302; viii. 418. Davy (Sir H.), electro-chemical theory, subsidiary hypothesis to, viii. 170. (Dr.) on the torpedo, i. 67 ; vi. 57 ; on the recent volcano in the Mediter- ranean, iii. 148 ; v. 453 ; note on, iii. 447 ; on the combinations of carbonic acid and ammonia, iii. 457 ; on the temperature of some fish, vi. 375 ; Prof. Faraday in reply to, vii. 337; viii. 521 ; Dr. Daubeny's reply to, viii. 249. (Prof.), experiments to prevent corrosion Isy sea- water, vii. S89 ; on nicotin, vii. 393. Dawes (Rev. W. R.), micrometrical measures of double stars, v. 302. Dease and Simpson's discovery of the North-west passage, xii. 542. Death, on the nature of, iv. 360. DeCandolle (M.) on the conditions of germination, reply to, viii. 491. Decomposition, chemical, effected by the magneto-electric current, i. 161. , electro-chemical, the nature and extent of, iv. 294. Decrepitation, on, ix. 316. De la Beche (H. T.) on the anthracite found near Bideford, vi. 67 ; on the trappean rocks with the new red sand- stone, vii. 513. De la Rive ( Prof.) on an optical phaeno- menon observed at Mont Blanc, xii. 122; on the interference of electro- magnetic currents, xii. 122. De la Rue (W.) on voltaic electricity. ix. 484 ; on a voltaic battery charged with solution of sulphate of copper, X. 244. Del Rio (A.) on Riolite and Herrerite, viii. 261. Deluge, Greek traditions of the, iv. 414 ; V. 25. Demonville on the diurnal variation of the magnetic needle, xi. 1 94. De Morgan ( Prof.) on the relation be- tween the number of faces, edges, and corners in a solid polyhedron, xii. 323. Denbighshire, Cefn caves in, i. 232. Denham (Capt.) on the survey of the Mersey and the Dee, vii. 487 ; on the vibration of railways, viii. 70. Denmark, King of, his encouragement of science, i. 16; on the geology of, vii. 412; viii. 553; on some changes of level which have taken place in, xi. 309. Density of liquids, on the, xii. 1. Derbyshire, on the geology of, iv. 66 ; on the limestone and gritstone district of, ix. 173. Deshayes (M.), the WoUaston Donation Fund awarded to, viii. 311. Despretz (M.) on the maximum density of liquids, xii. 1. Detection of foreign matters diffused in the atmosphere, on the, xi. 56. Devonshire, geology of, ix. 495 ; x. 388; xii. 510, 564; on the physical struc- ture of, xi. 311; on the subdivisions and geological relations of its old stra- tified deposits, xi. 315 ; Goniatites, xi. 317. Dew-point, on the, vi. 182 ; ix. 187, 398; vii. 256, 266. 313, 409, 470; on the deduction of the, from the indica- tions of the wet-bulb thermometer, xi. 54. Diamond, structure and origin of, iii. 219; vii. 245; probability of being made, ix. 230. Diastase, its action on starch, x. 247. Diathermal bodies, transmission of calo- rific rays through, vii. 475. Diatomeae, doubtful nature of the, xi. 389; siliceous envelopes of the, xi. 389; classification of, xi. 390. Dickinson's (Commander) account of the recovery of the stores of the The- tis, iv. 367. Didelphis hortensis, a new species of opossum, xii. 215. Diffraction, experiments on, ix. 403. Diffusion, gaseous, xi. 559. Dillenius (Prof.), notice of, viii. 424. Dimorphism of baryto-calcite, vi. 1 ; of chromate of lead, xii. 387. LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 — 1838. 19 Diodontus insignis, D. gracilis, and D. corniger, habits of, xii. 16. Diomedea, the genus, vi. 387. Dioptric light, new, x. 176. Diopsis, new species of, vii. 519. Diplodus gibbosus, xii. 86. Dipus Mitchellii, a new species of Aus- tralian Rodent, xii. 96. Disinfecting properties of supporters of combustion, i. 386. Disjota on the Rev. J. H. Pratt's de- monstration of a proposition in the ** Mecanique Celeste," ix. 84. Dispersion of light, on the formula for the, ix. 116; theory of the, x. 221. Divergence of plants, ix. 17; the cause of motion in plants, vii. 357. Diving of aquatic birds, on the, i. 23. Diving animals, on their circulating or- gans, vii. 502. Diving-bell, used in raising the stores of the Thetis, iv. 363, 367. Doebereiner (M.) on some new combina- tions of platina, v. 150; ix. 314, 544; method of obtaining spongy platina, x. 154. Dog, wild, description of a, iv. 62, 378 ; want of sagacity in a, ix. 67. DoUond (G.) on a concave achromatic lens adapted to the wired micrometer, iv. 364. Don (Prof.) on the aestivation of certain plants, ii. 377 ; on some British ferns, iv. 310 ; on deviations from the ordi- nary structure in Telopea speciocis- sima, V. 70; descriptions of Indian Gentianeac, viii. 75; on two species of Pinus, viii. 255 ; on Nephrodium rigidum, viii. 255; on varieties of Erica ciliaris and Tetralix, viii. 256 ; on two species of Coniferae, x. 73. Doniuni, a new metal, ix. 156; experi- ments on, ix. 255. Douay, Congres Scientifiques at, vii. 237. Douglas (Mr.), observations on the west- ern coast of North America, xi. 91. Dove ( H. W.), outlines of a general the- ory of the winds, xi. 227, 353. Dragon's-blood tree of Socotra, x. 226. Draper ( Prof.) on gaseous diffusion, xi. 559. Drinkwater (Mr.) on the telescope, i. 9. Drummond's light, on, viii. 238. Dublin meeting of the British Associa- tion, vii. 289, 385. , account of the magnetical obser- vatory at, xii. 119. Dudley coal-field, on the, x. 313. Dufresnoy , (M.), analysis of plomb- gomme, ix. 75. Dukhun, atmospheric tides and mete- orology of, vi. 59. Dumas (M.) on pyroxylic spirit and methylene, vii. 427 ; on camphor, x. 420; on carbovinate and potash, xi. 320 ; on the constitution of some or- ganic acids, xii. 38 1 ; on tartaric and paratartaric acids, xii. 605. Dumasine, on, xii. 108. Dunn (A.) on the atmosphere of his white-lead manufactory, vii. 77. Durand (H. M.) on the fossil jaw of a gigantic quadrumanous animal, xi. 33. Dutrochet's experiments on the respira- tion of plants, xi. 536. Dynamics, on a general method in, iv. 436; vi. 298. , geological, xii. 517. EW. B. on the frequent deficiency • of the ungueal phalanx in the orang outang, vii. 72; on the consoli- dation of the new red sandstune, vii. 515 ; note on Mr. Challis's paper on capillary attraction, viii. 172; on the silent flight of Musca voraitoria, x. 327. Ear, on the anatomy and physiology of, i. 375. Earnshaw (S.) on Prof. Moseley's prin- ciple of least pressure, iv. 89, 271 ; re- ply to, iv. 194,420. Earth, on the electro- and thermo-mag- netism of the, i. 310; on the Caven- dish experiment for determining the mean density of, xii. 283. , surface of the, on the probable effect of the transfer of pressure from one part to another of the, xi. 212 ; letter from Sir J. F. W. Herschel in explanation of, xi. 214. , porcelain, composition of, x. 348. Earthquake of Chili, viii. 74, 148 ; of Syria, xi. 204. waves, their effects on the coasts of the Pacific, viii. 181. Earthquakes at Chichester, vii. 208. , theory of the cause of, xii. 584. Earth-worm, vegetable mould produced by the digestive process of, xii. 89, 5 1 8. East India Company's present of tlieir herbarium to the Linna^an Society, i. 7 1 . Eaubonne (M. d') on the conservation of living plants, xi. 566. Eblanine, examination of, xii. 98. Echidna, remarks on the, v. 146. Echini, subdivision of, vii. 328 ; mode of preserving, vii. 493. Echinodermata, growtli and bilateral sym- metry of, V. 369. Echoes, modifications of, vi. 32. Eclipse, solar, viii. 293,589, 590; of May 15, 1836, ix. 73; x. 180; remarkabltt phsenomenon that occurs in, x. 230. C 2 20 GENERAL INDEX OF VOLS. 1 — 12 OF THE Edinburgh Observatory, longitude of, xii. 525. Edmonds ( R. ) on the meteor, June 29, 1832, i. 306 ; on the visibility of stars by day, iii. 238 ; on the mirage, viii. 1 69. Education, scientific and general, viii. 432. Edwardsite, a new mineral, xii. 402. Egerton (SirP.G.) on the ossiferous caves of the Hartz and Franconia, v. 296; on a stratum of recent marine shells in Cheshire, vii. 326; on Ichthyosauri, vii. 414 ; on the discovery of Ichthyo- lites in N. Staffordshire, vii. 517; ca- talogue of fossil fish, viii. 367 ; on the peculiarities of structure in the cervical region of the Ichthyosaurus, ix. 500. Egyptians, on the complexion of the, xii. 344. Ehrenberg (Dr. ), notice of his collections of dried Infusoria, and other micro- scopic objects, ix. 90; new discovery in palaeontology, ix. 158, 392 ; on the adulteration of carmine, xii. 462. Elastic bodies, on the collision of, viii. 65, fluids, evolved from volcanos, iii. 1 59 ; vibratory motion of, in tubes, iii. 235, mediums, on the motion of small spherical bodies in, i. 40. Elasticity of cast iron, i. 74 ; modulus of, of gold, iii. 20. Electric spark from a natural magnet, on an, i. 49. currents, new instrument for mea- suring, iv. 293. storm, description of a, v. 418. action, on, v. 6. light, duration of, vi. 61. Electrical influence, mathematical laws of, ii. 350. kite, caution to experimenters with, V. 317. Electricity, x. 12, 57, 60, 63, 65, 93, 130, 133, 154, 171, 172, 175, 193, 241, 244, 267, 276, 280, 281, 317, 320, 326, 357, 358, 376, 425, 428, 433, 455 ; experi- mental researches in, i. 61 ; iii. 38, 161, 253, 353, 449, 460; v. 161, 252, 334, 424, 456; vi. 34, 125, 171, 272, 334, 410; vii. 411, 421 ; xii. 206, 358, 426, 430 ; of the torpedo, i. 67 ; on the the- ory of magnetic, ii. 201, 366 ; the velo- city of, iii. 81 ; theory of thermo-elec- tricity, iii. 205, 262; recent discoveries in, iv. 291; on certain phaenomenaof, iv. 340 ; on some elementary laws of, iv. 436 ; of tourmaline, v. 1 33; experiments to measure the velocity of, vi, 61 ; its in- fluence in germination,'vi. 157 ; vindi- cation of Prof, Faraday's discoveries, vii, 421 ; electrical attraction, vii, 304; elec- trical balance, vii. 303,304; prismatic decomposition of electrical light, vii. 299; electric currents through platinum wire, vii. 388 ; viii. 114, 130, 400, 421, 455, 550; on the conducting power of flames and of heated air for, ix. 176 ; dif- ference between mechanical and galva- nic, ix. 212; M. Nobili's discoveries in, ix.234; electro-pulsations and electro- momentum, ix. 1 32 ; voltaic, due to che- mical action and not to contact, ix. 60 ; on the construction of voltaic batteries, ix. 283; new electro-chemical phaeno- mena, ix. 53; electro-magnet, its feeble attraction for small particles of iron, ix. 72, 220, 287 ; electro-magnet and per- manent magnet, certain differences be- tween, ix. 81 ; conducting power of iodine for, ix. 450 ; remarkable results of electro-magnetic experiments, ix. 452 ; voltaic, ix. 484 ; xii. 225 ; con- ducting powers of wires for, xi. 192; researches into the cause of voltaic, xi. 274 ; chemical composition of the elec- trical apparatus of the torpedo, xii. 256; current electricity, xii. 18, 293, 311, 539;electro-dynamicinduction,xii. 18; electro-magnetic currents, interference of, xii. 122; magnetic contact-breaker, xii. 18; electro-magnetic motive ma- chines, on, xii. 190; researches relative to the torpedo, xii. 196; peculiar vol- taic conditions of iron and bismuth, xii. 48 ; voltaic combination, xii. 364 ; on the primary forces of, xii. 486 ; ca- loric, and ponderable bodies, analogy between, v. 1 10. Electro-chemical theory of Sir H. Davy, subsidiary hypothesis to, viii. 170. Electro-magnet, its power to retain its magnetism, iii. 122 ; curious properties of, iii, 124, Electro-magnetism, vii, 231; of metal- liferous veins, iii. 16, 17; on certain experiments in^ iii. 18; experimental researches in, iii. 145 ; on its applica- tion to manufactures, vii. 305, 306. Electro-magnetic rotation, viii. 521 ; ba- lance, X. 358; machines, x. 12, 455. conducting powers of wires, xi. 1. Electro-motive battery, a new, i. 48. Electrophorus, on a modification of Vol- ta's, ii. 363. Elevation, on the parallelism of contem- poraneous lines of, iv. 404. Elliptical polarization, cause of, xii. 10. Emetine, preparation of, xi. 165. Emmett (Lieut.- Col.) on the carbonic acid in the atmosphere, xi, 225 ; me- teorological observations made at Ber- muda in 1836-37, and notice of an au- LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 — 1838. 21 rora borealis seen in low latitudes, xii. 42. Emmett (Prof.) on the preparation of formic acid, xi. 399. Enamel, art of painting in, x. 442. Encke's comet, observations of, i. 287; V. 304. Encke ( Prof.) on Olbers's method of de- termining the orbits of comets, vii. 7, 123, 203, 280. Enharmonic organ, vii. 366. Entomological Society, v. 236 ; vii. 420. Entomology : — a new genus of Melo- lonthidse, vii. 224 ; a species of moth found in the galls of a plant, vii. 224 j new Hymenoptera, vii. 228 ; x. 440 ; descriptions of new species of Diopsis, vii. 519; compound eyes of insects, viii. 202 ; on the yellow fly, viii. 347 ; '* Samouelle's Useful Compendium," viii. 412; undescribed species of Ara- neidaD, viii. 481 ; x. 100; harvest-bug, ix.l5; Aphrophora Goudoti, ix. 139; lulus Seychellarum, Desj., ix. 140; re- spiration of insects, ix. 532; voluntary sounds of insects, x. 327 ; on the tempe- rature of insects, xi. 189; on the sup- posed production of insects, xi. 551; oeconomy of several species of Hyme- noptera, xii. 14; on the family of Ful- goridae, xii. 93 ; Curtis's " Guide to an Arrangement of British Insects," xii. 202; several new species of in- sects of the family of sacred beetles, xii. 441. Entozoa of the human subject, vii. 506; in the stomach of the tiger, xi. 128. Entozoon, new species of, vi. 452. Enys (J . S.) on the granite near Penryn, ii. 321, 483. Equations, on the roots of, ii. 60, 220; iii. 417; interesting case in, v. 188; of the fifth degree, vii. 202; viii. 538 ; ix. 28 ; xii. 116; numerical, vii. 384; transformation of, vii. 478 ; congene- ric surd, viii. 43 ; algebraic, viii. 402 ; new method of solving, xi. 239. Equilibrium of fluids, on, xii. 385. Equinoctial gales, on, viii. 187. Equivalents of potash, soda, and silver, on, xii. 324. Erdmann (M.) on the oxalhydric acid of M. Guerin, xi. 142. Eriogoneae, on the, vi. 379. Escholzia californica, juice of, vi. 77. Essex (Alfred) on the art of painting in enamel, x. 442. Ethal, on, ix. 154. Ettrick (W.) on the solar eclipse of May 15, 1836, and on the aurora borealis of April 22, ix. 73. Eulima, notes on tliG genus, iv. 458. Euphorbiacese and Asclepiadea;, milk- vessels of the, xi. 520. Eupion and paraflfin, on, i. 402. Europe, experiments made in, xi. 254 ; on the diurnal inequality wave on the coasts of, xi. 1 95. Evaporation, explanation of, ii. S54. Everitt (Thos,)on the reaction of ferro- cyanuret of potassium and dilute sul- phuric acid, and on preparing hydro- cyanic acid from ferrocyanuret of po- tassium and sulphuric acid, vi. 101 ; oeconomical means of obtaining pure salts of manganese, vi. 193. Exley (T.) on Mossotti's theory of phy- sics, xi. 496. Expansion of solids^ new register-pyro- meter for measuring, i. 197, 261. Eye, effect of compression and dilatation on the retina of the, i. 89 ; on a new membrane of the, i. 1 13 ; iii. 87 ; ex- periments on the effect of light on the retina, i. 255 ; on certain changes of colour in the choroid coat of, iii. 289 ; blood-vessels of the, iv. 115, 354; in- fluence of successive impulses of light on, iv. 241 ; vascular spectrum of the, iv. 262 ; on the spectra of the, v. 1 92 ; unusual affection of the, vi. 281 ; cu- rious facts respecting vision, vi.409 ; of the Sepia Loligo, viii. 1 ; crystalline lens, viii. 193, 195, 416 ; symmetrizing power of the, x. 234, 370 ; polarizing structure in tlie crystalline lens after death, xii. 22 ; on cataract, xii. 25. Eyes of animals, on the, iv. 14 ; com- pound, of insects, viii. 202. FW. Optical experiment, viii. • 168. Fairbairne (Mr.) on hot- and cold-blast cast iron, xi. 556. Fairholrae (G.) on the spider's power to escape from an isolated situation, i. 424 ; on a species of natural microme- ter, &c., ii. 64 ; on the nature of coal, and mode of deposition of coal strata, iii. 245; on the Falls of Niagara, v.l 1. Falconer (Dr.) on the Sivatherium gi- ganteum, ix. 193, 277; on a fossil monkey from the tertiary strata of the Sewalik hills, xi. 393 ; on additional fossil species of Quadrumana from the Sewalik hills, xii. 34. Fallows ( Rev. F. ), memoir of the, i. 234. Faraday ( Prof.) on M. Negro's magneto- electric experiments, i. 45 ; on experi- mental researches in electricity, i. 61 ; iii. 38, 161, 253, 353, 449, 460; v. 161, 252, 334, 424, 456; vi. 34, 125, 171,272,334,410; vii.411; viii. 114; xii. 206, S58, 426, 430, 538 ; on tht GENERAL INDEX OF VOLS. 1 12 OF THE identity of electricity, &c., ii. 312 ; on the prevention of the dry-rot, ii. 313; on holding the breath for a lengthened period, iii. 241 ; discoveries in mag- neto-electric induction, on, iv. 11 ; re- cent discoveries in electricity, iv. 291 ; on the magneto-electric spark and shock, V. 349, 444 ; reply to Dr. Davy, vii. 337 ; M. PoggendorfF on his dis- coveries, vii. 421 ; royal medal award- ed to, viii. 150 ; on the magnetic rela- tions and characters of metals, viii. 179 ; on a supposed new sulphate and oxide of antimony, viii. 476 ; on the condensation of tlie gases, in reply to Dr. Davy, viii. 521 ; on a peculiar vol- taic condition of iron, ix. 57, 122 ; on the causes of the neutrality of iron in nitric acid, x. 175. Farish (Prof.), notice of, xii. 437. Farquharson (Rev. J.) on the ice formed at the bottom of running water, vii. 137. Farre (Dr.) on the structure of Polypi, xi. 189. Feathers, process for taking impressions from, xii. 451. Fedia, on the species of, vi. 380. Felis marmorata, a new species, x. 481 j F. Darwinii, on the, xii. 213. Fellenberg (M.), method of dissolving iridium, xii. 141. Fermentation, vinous, acetous, and pu- trefactive, ix. 535. of sugar of milk, xii. 139; action of, on a mixture of oxygen and hydro- gen gases, xii. 607. Ferns, on the structure of, iv. 253 ; re- marks on some British, iv. 310. Ferrocyanuret of potassium and dilute sulphuric acid, on the reaction of, vi. 97. Ferussac (Baron), notice of, x. 310. Fever, use of chloride of soda in, viii. 64. Fibres of cotton, form of, vi. 170, 231. Fielding (G. H.) on a new membrane of the eye, i. 113 ; iii. 87 ; on the struc- ture of the eyes of animals, iv. 14. Figures of vibrating surfaces, iii. 144. Fish, on the classification of, v. 459; temperature of some, vi. 375 ; notes on various species of, ix. 67, 139, 140, 352, 391, 490, 507 ; mode of preservation, ix. 391 ; fossil, xii. 86. Fisher (W.W.), accountof a case of spina bifida, X. 316, 486. (Rev. G.) on the nature and ori- gin of the aurora borealis, vi. 59. Fishes, collection of, from Madeira, iv. 380 ; of the river Quorra, vii. 64 ; of the island of Rathlin, vii. 492 ; fossil beaks of four extinct species of, viii. 4 ; fossil, viii. 72, 366. Fitch (R.) on the coralline crag, vii. 463. Fitton's (Dr.) notes on the history of English geology, i. 147, 268, 442 ; ii. 37 ; notice on the section of the coast near Hastings, iv. 49 ; on the Portland and Purbeck strata, vii. 323. Flame from coal-gas, phenomena of, vii. 404. Flames, chemical, spectra of, ix. 3 ; gal- vanic, spectra of, ix. 4 ; conducting power of, for electricity, ix. 176. Flamingo, anatomy of, ii. 71. Fiamsteed and Newton, viii. 139, 211, 218,225. Flint-glass, on the reflection at the se- cond surface of, at incidences of total reflection, i. 57. Floating bodies, motion of, vii. 302. Flower, structure of the, ii. 125. Fluids, elastic :— evolved from volcanos, iii. 159 ; vibratory motion of in tubes, iii. 235 ; atomic constitution of, v. 33 ; specific heat of, vii. 385. , on the resistance of, vii. 302 ; mo- lecular forces of, viii. 89. , aeriform, specific heats of, xii. 101 . Fluorine, on, ix. 107, 149 ; xii. 105. and chlorine, combinations of chro- mium with, ix. 151. Fluor spars, muriatic acid in, v. 78. Fog -bow, on a singular, ii. 151. Fogs, low, and stationary clouds, xii. 355. Forbes (Prof.) on an electric spark from a natural magnet, i. 49 ; on the relative positions of Chamouni and the con- vent of St. Bernard, ii. 61 ; on the pro- gress of meteorology, iii. 131 ; oncer- tain vibrations in metallic masses hav- ing different temperatures, iii. 303 ; iv. 15, 182 ; on the electricity of tourma-' line, V. 133 ; on the refraction and po- larization of heat, vi. 134, 205, 284, 366 ; vii. 349 ; xi. 542 ; xii. 545 ; on the undulatory theory of heat, viii. 246 ; the Keith prize awarded to, viii, 424 ; on the mathematical form of the Gothic pendent, viii. 449 ; on the tem- peratures of certain hot springs, and on the verification of thermometers, viii. 551 ; on the supposed origin of the de- ficient rays in the solar spectrum, ix. 522 ; on the physical development of man, x. 197 ; on the ascent of moun- tains, X, 261 ; on terrestrial magnetic intensity, xi. 58, 166, 254, 363 ; on the magnetic dip, xi. 370 ; on meteors, xii. 85. Forchamraer (G.) on changes of level which have taken place in Denmark, xi. 309. Forests, subterranean, iv. 282. LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 23 Formic acid, preparation of, iii, 313; ar- tificial preparation of, xi. 399. and acetic acid, difference between, iii. 73. acid and ulmin, conversion of sugar into, vi. 399. Forster's (Capt.) pendulum experiments, on, iv. 230. Forster (Edward) on the Esula major Germanica of Lobel, x. 71. Fossils : — remains in the limestone near Edinburgh, iv. 77 ; zoology, on, ii. 473 ; plants, ii. 475 ; vii. 487 ; fruits, iii. 76 ; bone caverns, iii. 237 ; col- lected in Cutch, V. 217; fossil wax, V. 316; scales, analysis of, vii. 396; wood, veins of crystallized carbonate of lime in, vii. 76; Polyparia, vii. 483; fossil fish, v. 461 ; vii. 485; viii. 72 ; trees, vii. 487 ; Crustacea and Radiata, vii. 517; genera Pseudam- monites and Ichthyosiagonites, ix. 32; Sivatherium giganteum, ix. 1 93, 277 ; remains, ix. 244, 352, 354, 386, 490, 498 ; wood, ix. 499 ; of the London clay, ix. 462; beaks of the Chimaera, viii. 4; catalogue of fossil fish, viii. 366 ; vertebra; of fish, viii. 557 ; vegetable remains, viii. 574 ; jaw of a gi^jantic quadrumanous animal, xi. 33; fossil monkey, xi. 393; ferns, xii. 95; fishes in the Lancashire coal-field, xii. 86 ; Quadrumana, xii. 34. Foster (Capt.), account of, i. 238. Fourier (M.) on an error in his " Ana- lyse des Equations," xi. 38. Fox of the Himalayan mountains, x. 304. Fox (C.) on the construction of skew arches, viii. 299 ; on the oblique arch, x. 167. (11. W.) on the magnetic needle, and the electro-magnetism of the earth, i. 310; on the igneous hypo- thesis of geologists, i. 338 ; on a ma- rine deposit in the cliffs near Falmouth, i. 47 1 ; sketch of the granite district near Penryn, ii. 322; on an instru- ment for ascertaining various proper- ties of terrestrial magnetism, iv. 81 ; on magnetic attraction and repulsion, v. 1 ; on electrical action, v. 6; elec trical relations of metals and metalli- ferous minerals, vi. 300; on the abs- ence of magnetism in cast iron in fu- sion, vii. 388 ; on the laws of magnetic attraction, vii. 439 ; on the magnetic forces, viii. 108 ; on the change in the chemical character of minerals in- duced by galvanism, ix. 228 ; on the formation of mineral veins, ix. 387 ; results of his experiments on the pro- duction of artificial crystals, x. 171 ; on the process by which mineral veins have been filled, xi. 203; on the tem- perature of some mines in Cornwall and Devonshire, xi. 520. Fractions, vanishing, viii. 295,393, 515; theory of, ix. 1 8, 92, 209. Francis ( W. ) on the motion of certain Po- lygastrica,xi. 448; notice of Wiegmann's " Herpetologia Mexicana," viii. 410. Freshwater formation in the Pyrenees, on a, iv. 376. Fresnel's law of double refraction, viii, 104, 248 ; x. 43 ; theory of double re- fraction, on, X. 24 ; optical theory of crystals, analytical reduction of, xi. 462; xii. .73, 259, 341 ; wave-surface, method of finding the equation to, xii. 335. Freyer (Lieut.) on the elevation of land on the coast of South America, vii. 318. Fritsche's experiments on pollen, xi. 165. P>og, contractions of the, xii. 197. Fruit,[structure of, ii. 1 29. Fulgoridae, on the, xii. 93. Fumar acid, composition of, xi. 164. Functions, calculus of, on a paradox in, ix. 334, 443. Fungi, hymenium of,x. 492. Furs, method of dressing, so as to pre- serve their colour, &c., iii. 297. Fusion of metals, i. 202. Fuss's ( M. G.) magnetical and meteoro- logical observations at Pekin, i. 130. Fyfe (Dr.; on the use of sulphate of cop- per for exciting voltaic electricity, xi. 145 ; on the employment of iron in the construction of voltaic batteries, xi. 150. G on a property of the parabola, x. Gadolinite, analysis of, vii. 430; xi. 143, Gaging, on the art of, iv. 326. Gahn's blowpipe, modification of, xi. 58. Gale (Dr.) on Prof. Mitchell's method of preparing carbonic oxide, vi. 232. Galictis, on the genus, xii. 529. Gallic acid, on, xi. 323 ; speedily prepared, vi. 319; formation of, xi. 163. Galloway (T.) on the solar eclipse. May 15, 18*36. viii. 589. Galvanic shock-multiplier, on the, xi. 460. Galvanism : — spectra of galvanic flames, ix. 3; galvanic pile, its application to chemical substances under tlie micro- scope, ix. 13; difference between gal- vanic and mechanical electricity, ix. 212 ; change in the chemical character of minerals by, ix. 228; new galvanic battery, ix. 472. GalvancHueter, its efficiency for determi- 24 GENERAt INDEX OF VOLS. 1 12 OF THE ning the conducting power of wires, xi. 8 ; on a tliermoscopic, xi. 378, Gambart's comet, observations of, i. 287. Gardner (Mr.) on the structure of the wood of palms, xi. 553. Garner ( It. ) on the anatomy of the la- mellibranchiate conchiferous animals, ix. 224. Garnet in the millstone-grit, vi. 76. Gaseous combination, action of metals in determining, vi. 354. — interference, on, ix. 324. Gases, on the law of the diffusion of, ii. 1 75, 269, 351 ; from springs at Bath, on, iv. 221, 225; action of, on vegetation, iv. 316; on Mr. Graham's law of the diffusion of, iv. 321 ; from springs near Vesuvius, vii. 316; specific heats of, viii. 21 ; condensation of, viii. 521 ; contained in the blood, xii. 300 ; oxy- gen and hydrogen, action of fermenta- tion on, xii. 607. Gasteropoda, new genus of, v. 312. Gastric juice of dogs, composition of, ix. 148. Gaudichaud (M.) on the circulation of the sap in Cissus hydrophora, xi. 525. Gaudin (M.) on the artificial production of rubies, xi. 563. Gauss (Prof.) on terrestrial magnetism, ii. 291. Gay Lussac (M.) on the purification of carbonate of soda, v. 316 ; on the assay of silver, vii. 425 ; on the decomposi- tion of carbonate of lime by heat, x. 496 ; on siliceous and calcareous pro- ducts, xi. 403. Gentianea?, descriptions of Indian, viii. 75. Gentianin, on, xii. 221. Geoffroy St. Hilaire on the mammary glands of the Ornithorhynchus, iii. 60, 62 ; iv. 54. Geoghegan (Prof.) on muriatic acid in hydrocyanic acid, vii. 400. Geological Society, proceedings of, ii. 147,300,466; iii. 42, 219, 368; iv. 48, 147, 225,370, 441; v. 53, 211, 292, 459; vi. 63, 146, 312, 376; vii. 52, 212, 316, 412, 513; viii. 71, 156, 310; ix. 382, 489; x. 68, 136, 306, 388, 471; xi. 98, 201,307, 390; xii. 86, 284, 433, 508, 564. . , anniversary meetings of, ii. 466; iii. 42;iv.442; v. 53; vii. 54, 142, 212; X. 308, 388 ; xii. 434. Geological Society of Cornwall, vi. 153. Geology :— notes on the history of En- glish, i. 147, 268, 442 ; ii. 37; of the south-east coast of Newcastle in Aus- tralia, i. 92 ; on the igneous hypothe- sis in, i. 338 ; oti recent deposits, ii. 470 ; on tertiary deposits, ii. 472 ; on fossil zoology, ii. 473 ; on the chemistry of, iii. 20; of Northum- berland and Durham, iii. 28, 92, 200, 273 ; discovery of coal-measures and fossil fruits in Leicestershire, iii. 76, 112; of the environs of Bonn, iii, 220 ; sedimentary deposits of Shropshire, Herefordshire, &c., iii. 224 ; fossil- bone caverns, iii. 237 ; on the nature of coal, and on the mode of deposition of the coal strata, iii. 245; on the Squa- lo-raia Dolichognathos, iii. 369 ; or- ganic remains, iii. 369,371; vii. 483, 485, 487 ; viii. 577 ; ix. 462 ; x. 402 ; on the osseous cave of Santo Giro, iii. 371 ; report on the science of, iv. 427; on the Falls of Niagara, v. 1 1 ; on the future extension of the English coal- fields, V. 44 ; discovery of bones of the Iguanodon, v. 77; on the stratification of Derbyshire, v. 121 ; on the quan- tity of solid matter suspended in the Rhine, v. 211, 223; geology of Read- ing, V. 212 ; on the Temple of Serapis at Pozzuoli, V. 213; views respecting geological cycles, V. 215; variations of temperature in a thermal spring at Mal- low, V. 216 ; on the delta of Kander, V. 216; fossils collected in Cutch, v. 217 ; on the gravel and alluvial depo- sits of Hereford, Salop, and Worcester, v. 217 ; notice of the coast from Whit- stable to the North Foreland, v. 219; on the ravines, passes, and fractures in the Mendip hills, v. 220 ; on the ter- tiary formation ofMurcia, v. 220 ; geo- logy of the Bermudas, v. 222 ; on the organic remains in the lias series of Yorkshire, v. 222; on certain trap rocks in Salop, &c., v. 225, 292 ; ob- servations on wells dug at Diss and Hampstead, v. 295; on the ossiferous caves of the Hartz and Franconia, v. 296 ; on the occurrence of freshwater shells beneath the gravel, v. 297 ; on subterranean temperature, v. 446 ; geo- logical distribution of fossil fish, v. 461 ; saurian bones found in the mag- nesian conglomerate, v. 463; geologi- cal survey of the United States, v, 466 ; on the raised beach near Hope's Nose, Devonshire, vi. 63 ; on the cen- tral and western portions of N. Ame- rica, vi. 64 ; on the anthracite found near Bideford, vi. 67 ; fossil plants, vi. 67 ; viii. 574 ; on the physical and geo- logical structure of the country to the west f the Dividing Range, between Hunter's River and Moreton Bay, New South Wales, vi. 146; land and freshwater shells found witli bones of land quadrupeds, vi. 149; bones ef LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 25 animals discovered in the calcareo- magnesian conglomerate, vi. 149 ; on the proofs of a gradual rising of the lapd in Sweden, vi. 297 ; on the chalk and flint of Yorkshire, vi. 313; on an outlying hasin of lias on the borders of Salop and Cheshire, and account of the lower lias between Gloucester and Worcester, vi. 314; general view of the new red sandstone series, in the coun- ties of Salop, Stafford, Worcester, and Gloucester, vi. 315 ; coal tracts in Sa- lop, Worcestershire, and N. Glou- cestershire, vi. 376 ; on the gold-woik- ings formerly conducted in the county of Wicklovv, vii. 1 ; advance of land in the Persian Gulf, vii. 40, 192, 250; Silurian system of rocks, vii. 46, 48;J ; proceeds of the Wollaston fund pre- sented to Mr. MantcU, vii. 52; veins of crystallized carbonate of lime in fossil wood, vii. 76 ; crag-formation and its organic remains, vii. 81, 353, 463, 464; viii. SB, 138, 529; x. 1; geology of Norfolk, vii. 171, 274, 353, 370; discoveries in the volcanic strata, vii. 316; on the elevation of land in South America, vii. 318 ; marine shells at Elie, Fifeshire, vii. 318; Shrews- bury, and in Cheshire, vii. 326,516; at Marley Bank, ix. 497; diluvium of Fincldey, vii. 319; structure of rocks, vii. 320, 376, 445 ; on the Portland and Purbeck strata, vii. 323 ; ichthy- olitcs of Gamrie, vii. 325; coraline crag of Ilamsholt and Orford, vii. 463 ; cre- taceous and tertiary strata of the island of Seeland and Moen, vii. 412 ; pecu- liarity of structure in tlie neck of Ich- tliyosauri, vii. 414; ix. 500; of North Salop and Staffordshire, vii. 415; geo- logical map of Ireland, vii. 480 ; on the granite of Cavan, vii. 482 ; on the Silurian and Cambrian systems, vii. 483; viii. 561; of Spain, vii. 485; newly discovered tertiary deposit, vii. 486 ; application of physical science to geological researches, vii. 489 ; trap- pean rocks with new red sandstone, vii. 513; fi §sil Crustacea and lladiata, vii. 517; discovery of Ichthyolites, vii. 517; bones of birds found in Tilgato Forest, vii. 518; geology of West Nor- folk, viii. 28; of fossil fishes in the new red sandstone, viii. 72 ; on the gradual sinking of the west coast of Greenland, viii. 72 ; earthquake of Chili, viii. 74 ; notes made during a survey of the cast and west coasts of S. America, viii. 156; effects proCiiccd j at Valparaiso by tlie earthquake of | Nov. 1822, viii. 159; effects of earth- quake waves on the coasts of the Pa- cific, viii. 181; on physical geology, viii. 227, 272, 357 ; catalo-ue of fossil fish, viii. 366; geological relations of cer- tain hot springs, viii, 551 ; geology of Denmark, viii. 553; occurrence of fossil vertebrae of fish in the loess of the Rhine, viii. 557 ; selenite in the sands of the plastic clay, viii. 558 ; transportation of rocks by ice, viii. 558 ; syenite veins which traverse the mica slate of Antrim, viii. 559 ; geo- logical structure of Pembrokeshire, viii. 561 , on the gravel and alluvia of S. Wales and Siluria, viii. 566; on a patch of red and variegated marls, viii. 571 ; on the streams of sea water in the island of Cephalonia, viii. 573 ; on the caves of Ballybunian, viii. 547 ; remains of mammalia found in the Se- walik mountains, viii. 575 ; on the os- siferous cavern of Yealm Bridge, \iii. 579 ; fossil genera Pseudammonites and Ichthyosiagonites, ix. 32 ; carboni- ferous series of North America, ix. 124, 407 ; geology of Manchester, ix. 157; the Sivatherium giganteum, ix. 193, 277; xi. 208; xii. 40; on the limestones found in the vicinity of Manchester, ix. 241, 348; grants of money for the advancement of geology, ix. 312; on the beds immediately above the chalk near London, ix, 356 ; geo- logy of Coalbrooke Dale, ix. 382; x. 311; formation of mineral veins, ix. 387 ; X. 394 ; on the Silurian and other rocks of the Dudley and Wolverhamp- ton coal-field, ix. 489; on the part of Devonshire between the Ex and Berry Head and the coast and Dartmoor, ix. 495; notice on Maria Island, ix. 496; on the upper' lias and marlstone of Yorkshire, ix. 497; tooth of a masto- don, ix. 499 ; remarks on fossil woods, ix. 499 ; on the coal-fields on the N. W. coast of Cumberland, ix. 501 ; on ter- tiary deposits, X. 1 ; anchor found at Seaton, x. 10; geology of Asia Mi- nor, X. 68 ; on changes in the level of sea and land in the weit of Scotland, X. 136; distribution of organic re- mains on the Yorkshire coast, x. 137 ; on a vein of bituminous coal in Cuba, X. 161 ; composition of porcelain earth, X. 348; on the carboniferous series of New York and Pennsylvania, x. 365; proofs of modern elevation and subsi- dence, X. 397; on hills of gravel con- taining marine shells, ix. 497 ; x. 47 I ; of the Thracian Bosphorus, x. 473 ; on some impre^^s'ons in sandstone, x. 474 ; silicified trunks of trees in new D 26 GENERAL INDEX OF VOLS. 1 12 OF THE red sandstone, x. 475 ; raised beach in Barnstaple bay, x. 477 ; fossil jaw of a gigantic quadrumanous animal, xi. 1 ; geology of Holguin in Cnba, xi. 17; colouring matter cf the greensand for- mation, xi. 36 ; mountain of La Silla, xi. 25; coral rock of Cuba, xi. 31 ; elevation of the strata on the coast of Chili, xi. 98, 100; a deposit containing land-shells at Gore Cliff, xi. 103; a trap dyke in the Penrhyn slate quar- ries, xi. 103; the strata usually termed plastic clay, xi. 104 ; geology of Suf- folk, xi. 106; keuper sandstone of the new red sandstone formation, xi. 106 ; geology of the Cotentin and Cher- bourg, xi. 107 ; of Cutch, xi. 107 ; physical features of Suffolk, xi. 11 1 ; on Saunton Downend and Baggy Point, xi. 117; occurrence of Anatifa vitrea on the Irish coast, xi, 135; ancient state of the North American conti- nent, xi. 201 ; of Smyrna, xi. 202; de- posits containing Mammalia, xi.206 ; remains of a quadrumanous animal, xi. 208 ; on some elevations of the coast of Banffshire, xi. 209 ; a ter- tiary deposit near Lixouri, xi. 209; of the coast of Normandy, xi. 210; a well at Beaumont green, in Hereford, xi. 215; affinity of fossil scales offish with those of recent Salmonidne, xi. 300; an elevation and subsidence in the Pacific and Indian oceans, xi. 307; changes of level in Denmark, xi. 309; physical structure of Devonshire, xi. 311; upper formations of the new red system in Gloucestershire, Worcester- shire, and Warwickshire, xi. 318; fos- sil monkey, xi. 393 ; geological phae- nomena in Christiania, xi. 555; fosiil quadrumana, xii. 34; fossil fishes in the Lancashire coal-field, xii. 86; of Zante, xii. 87 ; on the formation of mould, xii. 89; on a hitherto unob- served structure in certain trap-rocks, xii. 106 ; on the pha?nomena of mine- ral veins, xii. 125; unity of the coal deposits of England, xii. 127; on in- dications of recentelevations in Guern- sey and Jersey, xii. 284 ; on the great basaltic district of India, xii. 286; de- scriptive geology, xii. 508 ; geological dynamics, xii. 517 ; theory of volcanos, xii. 533 ; theory of volcanic pha;no- mena, xii. 576, 584 ; of Devonshire, xii. 510, 565 ; of Mazunderan, xii, 571 ; of the Birmingham and Gloucester railway line, xii. 573; insulated masses of silver, xii. 578 ; peat bogs and sub- marine forests of Bourne Mouth Val- ley, xii. 579 ; of Asia Minor, xii. 581 ; remarkable dykes of calcareous grit, xii. 584 ; on the dislocation of the tail of many Ichthyosauri, xii. 590. Geometry, spherical researches in, iii. 366 ; analytical, xii. 602. Geometrical series, analytical theorems relating to, vi. 196. Gergonne's '* Annales de Math6ma- tiques," a theorem from, ix. 100. German silver, analysis of, viii. 80. Germination, influence of electricity in, vi. 157; conditions of, viii. 491 ; che- mical changes in seed during, ix. 536. Gibraltar Scientific Society, viii. 256. Giesecke (Sir C. ), notice of, iv. 445. Gigantic animal, fossil jaw of a, xi. 33. Gilks ( Wm.) on the aurora borealis, Oct. 11, 1836, X. 77. Gill (Thos. ) on the fibres of flax and cotton, vi. 231. Giraffe, account of the capture of the, ix. 144,512. Giraud (H.) on teriodide of chromium, xii. 321. Glass, action of high pressure steam on, V. 297 ; action of sulphate of ammo- nia on, xii. 608 ; enamel, x. 444 ; painting, ix. 456; x. 443 ; on the art of, ix. 456. Glauberite, action of heat on, i. 417. Glen Roy, on the parallel roads of, vii. 433. Gloucestershire, on the upper formations of the new red system in, xi. 318. Goat, wild, description of, vi. 225. Gottingen, new niagnetical observatory at, V. 344. Gold, modulus of elasticity of, iii. 20; on the iodides of, ix. 266. — — — workings of "Wicklovv, Ireland, vii. 1. Goose, Sandwich Island, v. 233. Gopher-wood of the Scriptures, on, iii. 103; iv. 178, 280; v. 244; vi. 401. Gore Cliff, on a deposit containing land- shells at, xi. 103. Gothic architecture, progress of, vi. 395. pendent, on the, viii. 449. Gould (C.) description of a new object for the microscope, iii. 318. (3.), descriptions of various birds in the collection of the Zoological So- ciety, ix. 66, 142, 227, 522 ; x. 287, 290, 293, 295j xii. 215, 444, 527, 596, 598. Gradients on railways, viii. 51, 97, 243. Graham (Prof.) on the law of the dif- fusion of gases, ii. 175, 269, 351 ; iv. 321 ; on the arseniates, phosphates, and modifications of phosphoric acid, iii. 451, 459; reply to Mr. Phillips LOND. AND EDIN. PHILOSOPHICAL xMAGAZINE, 1832 1838. 27 on the use of chemical symbols, iv. 106, 402 ; Mr. Phillips's answer, iv. 246^; on phosphuretted hydrogen, V. 401 ; on water as a constituent of salts, vi. 327, 417 ; on certain com- pounds with water, vii. 400; on the water of crystallization of soda-alum, ix. 26 ; on the constitution of salts, X. 216; xi. 897. Granite, mode of working near Penrhyn, ii. 321, 322. Grant (Capt.) on the geology of Cutch, xi. 107. — — (T. T.) on protecting iron from the action of salt water, viii. 128. Graves (Dr.) on the use of chloride of soda in fever, viii. 64. — — (J. T.) on the logarithms of unity, viii. 281 ; explanation of a remarkable paradox in the calculus of functions, ix. 334, 443 ; on the symmetrizing power of the eye, x. 370. Gravitation, simple method of proving the law of, ix. 333, 370. Gray (Mr. J. E.) on the genus Para- doxurus, i. 397 ; on the structure of shells, iii. 452 ; on the reproduction of Cirrhipeda, iv. 65; description of the new genus Ganymeda, v. 73; on the animal of Argonauta, vi. 385; on two new species of sturgeon, vi. 386 ; on the type of a new genus nearly related to Bipes, vi. 391 ; on the difficulty of distinguishing certain genera of shells, vii. 210; on a new species of toad, and on the genus Echinus, vii. 328 ; on a new species of coral, vii. 419; on the genus Moschus and Cervus, ix. 515, 518; on the supposed production of insects, xi. 551. Great Britain, on the population of, i. 213. Greatheed (S. S.) on a new method of solving equations of partial differen- tials, xi. 239. Great Runn, account of the, xi. 110. Grecian buildings, on the entablature of, viii. 430. Greenland, on the gradual sinking of the west coast of, viii. 73. Greenough's (G. B.) address to the Geological Society, iv. 442; v. 53; vii. 54, 142. Gregory (Dr.) on a volatile liquid pro- cured from caoutchouc by destructive distillation, ix. 321 ; examination of eblanine, xii. 98; oo some remarkable salts, xii. 102. Gresham College, Prof. Pullen's lecture on astronomy, xii. 454. Grey (Lieut.) on the meteorology of Teneriffe, xii. 291. Griesselich (M.) on the glands in the leaves of Labiata;, xi. 530. Griffin (D.) on an unusual affiection of the eye, vi. 281. Griffith (R.) on the syenite veins which traverse the mica slate of Antrim, viii 559. Griffiths (Mrs.) on the vision of the re- tina, iv. 43 ; on the spectra of the eye and seat of vision, v. 192. Guerin (M.) on potatoe starch, viii. 586. Gum, action of chlorine on, ii. 405. Gums, analysis of, ii. 234, 244. HADFIELD (W.) on the circum- stances producing ignition in char- coal in atmospheric temperatures, iii. 1. Hall (Capt. B. ) on the want of perpendi- cularity of the standing pillars of the temple of Serapis, vi. 313. (Col.), meteorological observations made in Colombia, xii. 148. (Dr. M.) on the laws of mutual relation of respiration and irritability, i. 72; experiments on the decapitated turtle, vi. 71 ; description of a ther- mometer for determining minute dif- ferences of temperature, viii. 57 ; on the reflex function of the spinal mar- row, X. 51, 124, 187, 378. (Sir James), notice of, ii. 137 ; no- tice of the scientific discoveries of, ii. 468. Halley (Dr. E.), account of his astro- nomical observations, vi. 221 ; some particulars of his life, vi. 306 ; viii. 144, 214, 220, 225. Halley's comet, v. 284 ; vi. 45; vii. 139, 236, 423; viii. 148, 173; ix. 292; ephemeris of, ix. 296. Hallymeter for the examination of malt liquors, xii. 218. Hamilton (C. VV.) on a yew found in a bog, vii. 499. (Prof. Sir W. R.) on aberration in prismatic interference, ii. 191, 284; re- ply to, ii. 276 ; Mr. Potter's answer to, ii. 371 ; on a general method in dy- namics, iv. 436; vi. 298; Royal Me- dal awarded by the Royal Society to, viii. 150; theorem respecting algebraic elimination, viii.*^38; on equations of the fifth degree, ix. 28 ; exposition of the argument of Abel respecting equa- tions of the fifth degree, xii. 116; in. augural address delivered before the Royal Irish Academy, xii. 368. (W. J.) on a geological formation at Elie, vii. 318; on the geology of the Thracian Bosphorus, x. 473 ; xii. 581 ; on a tertiary deposit near Lixouri in Cephalonia, xi. 209. D2 28 GENERAL INDEX OF VOLS. 1 12 OF THE Hancock (Dr.) on heat-lightning, iv. 340. Handyside (Dr.) on the offices of lac- teals, lymphatics, and veins in the function of absorption, viii. 58. Harcourt (Rev. W. V.) on observations upon the dew-point, vii. 409. Harding (Prof.), notice of, v. 319. Hare (Dr. \ apparatus for freezing water, v. 377; voltaic trough, viii. 116, 119; on the difference between mechanical and galvanic electricity, ix. 213; che- mical philosophy and nomenclature, xi. 176 ; the grounds of his deviating from the language and arrangement of Berzelius, xi. 177; on ink devoid of free acid, xi. 324; on the congela- tion of water by hydric aether, xi. 325 ; on synthesis of ammonia, xi. 326; on the rotatory multiplier, xi. 327 ; com- munication respecting nomenclature, J. J. Berzelius's reply to, xi. 179 ; on sulphurous aether and sulphate of SBtherine, xii. 474. Harriot (Thos.), on some old MSS. of, i. 378. Harris (W. S.) on elementary laws of electricity, iv. 436 ; on an electrical balance, vii. 303 ; electrical attraction, vii. 304; on the attractive and repul- sive forces of magnets, viii. 349. Harrison ( Prof.) on the entozoa found in the muscles of the human subject, vii. 506; on bones in the hearts of certain animals, vi'. 506. Harvest-bug, description of the, ix. 15. Hartley (Mr.) on the corroding of iron by salt water, xi. 554. Hastings, on the geology of the coast near, iv. 49. Hatchetine, composition of. xii. 338. Hausmann (Prof.) on Mr. Whewell's account of his mineralogical works, V. 158. Hawfinch, x. 72. Haworth (A. H.) on Narcissineae, i. 275. Hay (Mr.), notices of plants of Marocco, ii. 409. Heart, on the tricuspid valve of the, vii. 207 ; influence of the respiratory or- gans on the, vii. 212; safety-valve of the, ix. 525. Heat: — produced by friction and per- cussion, i. 164 ; evolved by friction and percussion, i. 247 ; action of on glauberite, i.417; M. Fourier's law of the radiation of, ii. 103; influenceof, on colour and odours, iii. 458 ; action of, on iodide of aniidine, iv. 238; re- pulsive power of, vi. 58, 415; viii. 189; xii. 317; refraction and polari- zation of, vi. 134, 205, 284, 366 ; ra- diant, vii. 296, 297; viii. 23, 109, 186, 190, 246, 425; polarization of, vii. 349; xi. 543; volatilization of mag- nesia by, vii. 406 ; undulatory theory of, viii. 246 ; its circular polarization by total reflexion, viii. 246 ; xii. 317 ; has it weight? ix. 396 ; in uncrystal- lized media, transmission of, x. 336; physical causes of the phsenomena of, X. 342 ; action of cold air in maintain- ing, xi. 407, 446 ; its influence on the circulation of the Chara, xii. 457 ; re- searches on, xii. 545. Heat and light, on the production of by animals, vi. 246 ; the results of vibra- tory motion, vii. 342. Height, experiments on terrestrial mag- netic intensity, particularly with refer- ence to the effect of, xi. 166. Heights, measurement of, vii. 311. Heineken (Rev. N. S.) on the radii of curvature of convex lenses, vii. 234 ; on the aurora borealis of Nov. 18, 1835, viii. 439; on an anchor found at Seaton, x. 10; on the aurora bo- realis of Feb. 18, 1837, X. 265; on the galvanic shock multiplier, xi. 460 ; correction in his paper, xi. 567. Heliostat, on a new, ii. 6. Helm wind, on the, x. 221. Hemming's (Mr.) safety-tube for the combustion of oxygen and hydrogen, i. 82. Henry ( Dr. W. C.) on the atomic con- stitution of elastic fluids, v. 33 ; reply of Dt. Prout to, v. 132 ; on the action of metals in determining gaseous com- bination, vi. 354; experiments on ga- seous interference, ix. 324 ; notice of, X. 152. (J.) on the roots of equations, iii. 417. Henslow's clinometer, improvement in, V. 159. Henwood (W. J.) on the vaiiations in springs, i. 287 ; iii. 417 ; on intersec- tions of mineral veins, ii. 147; on certain meteorological phaenomena, iv. 103 ; iv. 233 ; on the steam engines of Cornwall, viii. 20, 591 ; on the phae- nomena of mineral veins in Cornwall, xii. 125. Herberger (M.) on cetrarin, xii. 296. Hereford, on a well at Beaumont Green, in, xi. 215. Heriades campanularum, xii. 18. Hermann (R.) on triple combinations ofchlLride of osmium, iridium, and platinum, with chloride of potassium and muriate of ammonia, ix. 232. Heron (Sir R.) on the kangaroo, ix. 67 ; LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 29 on the want of sagacity in a dog, ix. 67; on the breeding of curassows, ix. 121. Herrerite, viii. 2HI. Herschel (Sir J. F. W.) on the action of light in determining the precipitation of muriate of platinum by lime-water, i. 58; on subterrai»ean sounds, i. 221 ; on a remarkable deposition of ice round the stems of vegetables, ii. 110; observations on Biela's comet, ii. 222; on the elliptic orbit of | IJobtis, iii. 291 ; on the absorption of light by coloured media, iii. 401 ; observations of nebulae and clusters of stars, iv, 125 ; on the satellites of Uranus, iv. 381 ; micrometrical measures of double stars, V. 302 ; meteorological observa- tions, viii. 78 ; on scientific and gene- ral education, viii. 432 ; catalogue of double stars, ix. 295 ; the Royal medal awarded to, x. 213; on the probable effect of the transfer of pressure from one part to another of the earth's sur- face, xi. 212; on the peculiar voltaic condition of iron, xi. 329 ; on the re- markable increase of magnitude of n Argus, xii. 521, 526 ; on the theory of volcanic phaenomena, xii. 576. Hess (M.) on the fermentation of sugar of milk, xii. 139. Hieroglyphics, on Egyptian, iv. 170. Hodgkin ;Dr.)on the languages spoken by uncivilized nations, vii. 27, 94. Hodgkinson (E.) on impact and colli- sion, viii. 65. Hodgson (B. H.) on the wild dog of Nepal, iv. 62 ; on the mammalia of Nepal, vi. 150; on the wild goat and the wild sheep, vi. 225 ; on the Scolo- pacid» of Nepal, ix. 143 ; on a new species of Cervus, ix. 391. Hoffman, (Prof.), notice of, x. SOS. Hogg (J.) on the influence of the cli- mate of Naples on vegetation, iv. 274; v. 46, 102 ; specimen of a thermo- metrical diary, xii. 489. Holderness, ancient forest of, iv. 282. Holditch (Ilev. H.) on a property of the parabola, x. 35. Holdsworth (J.), discovery of coal measures and of fossil fruits in Lei- cestershire, iii. 76 ; Rev. W. D. Cony- beare's remarks on, iii. 112. Holguin, geology of, in Cuba, xi. 17. Holland (P. W.) on the question, has heat weight? ix. 396. Home, (Sir E.), sketch of his life, ii. 136. (Sir J.), magnetical observations made in the West Indies, &c., xii. 206. Honey of Trebizdnd, v. 313. Hood's (C.) <' Treatise on warming buildings," xii. 202. Hope (Dr.), address on presenting the Keith prize to Prof. Forbes, viii. 424 ; on the colours of plants, xi. 441. Hopkins (W.) on the geology of Der- byshire, iv. 66 ; on Mr. Farcy's ac- count of the stratification of the lime- stone diiitricts of Derbyshire, v. 121 ; on physical geology, viii. 227, 272, 357 ; Hopkins's •' Researches in Physical Geology," ix. 4, 171, 366; X. 14. Horizon-sector, on the, ii. 327 ; on the measurement of the instrumental error of the, i.98. Horner (L.) on the geology of the en- virons of Bonn, iii. 220; on the quan- tity of solid matter suspended in the Rhine, v. 211; vi. 396; on a sub- stance resembling shell, viii. 545 ; x. 201 ; on some geological phaenomena in Christiania in Norway, xi. 555. (W. G.) on the Daedaleum, iv. 36; on the vascular spectrum, iv. 262; on an interesting case in equations, v. 1 88 ; on the signs of the trigonome- trical lines, vi. 86 ; on congeneric surd equations, viii. 43 ; new demonstra- tion of an original proposition in the theory of numbers, xi. 456 ; theorem of, xi. 457 ; obituary notice of, xi. 459. Horsburgh (Capt.), notice of, x. 149. House- spider, observations on the, i. 95; power of, to escape from an insulated situation, ii. 152. Houston (Dr.) on the circulating organs in diving animals, vii. 502 ; on a va- riety of hydatid, vii. 5C4. Hudson (Dr. H.) on the dew-point, vii. 256; on the radiation of heal, vii. 297; on an error in Dr. Apjohn's formula for inferring the specific heats of dry gases, viii. 21 ; on the transmission of calorific rays, viii. 109; reply to Dr. Apjohn, ix. 398. Humboldt (Baron) on advancing the knowledge of terrestrial magnetism, ix. 42. Human body, efTects of compressed air on, ix. 147. Human voice, physiology of the, ix. 201, 269, 342. Hiinefield on the microscopical examina- tion of the coloured parts of vegetables, xi. 442. Hunt ( R.) on tritiodide of mercury, xii. 27. Hunton (L.) on the combinations of sugar with the alkalies and metallic oxides, xi. 152. 30 GENERAL INDEX OF VOLS. 1 12 OF THE Ilusseji's (Rev. T. J.) catalogue of co- mets, ii. 194,282,453; iii. 101, 198; iv. 29, 205, 349 ; vii. 36. Hutton's (W.) observations on coal, ii. 302. Hymia, tameable disposition of, iii. 296. Hydatid, on a variety of, vii. 504. Hydrate of ojI of turpentine, vii. 537 ; of potash, crystallized, ix. 151 ; of barytes and strontia, ix. 87 ; of mag- nesia, on, X. 454. Hydriodate of brucia, xi. 216,217; of quina, xi. 218. Hydriodic acid, a test for the vegetable alkalies, viii. 191. Hydrobromate of carbo-hydrogen (me- thylene), xi. 221. Hydrochloric acid, its action on certain sulphates, viii. 353; method of detect- ing sulphurous acid in, ix. 543. Hydrocyanic acid, preparation of, vi. 97. and cyanurets, conversion of into ammonia and formic acid, i. 83. Hydrogen, preparation of peroxide of, ii.403. phosphuretted, composition of, iii. 308; V. 401. ■ ■ antimoniuretted, x. 343. carburets of, xi. 404. — — and oxygen, safety -tube for the combustion of, i. 82. and platina, compound of, v. 155. Hydrometer, Prof. Stevelly's, viii. 69. Hydrometeors, their connection with the variations of the temperature and of the barometer, xi. 359. Hydrosulphuric and hydroselenic aethers, ix. 318. Hygrometer, wet-bulb, fornnula for in- ferring the dew-point from the, vi. 182; vii. 256, 266, 313,470. Hygrometrical researches, ix. 187, 398. Hylaeus signatus, xii. 18. Hymenium of fungi, x. 492. Hymenopterous insects, vii. 228; x. 440; economy of several species of, xii. 14. Hyperiodic acid, and hyperiodates, iv. 386. Hypophosphomesitylous acid, xii. 101. Hyrax Capensis, vii. 222. IBIS, on the sacred, ii. 231. Ice, deposition of, round the stems of vegetables, ii. 110; on a stone wall, ii. 190; on a rhombohedral crystallization of, iv. 245 ; at the bottom of running water, vii. 137. Ichthyolites of Gamrie, vii. 325 ; disco- very of, vii. 517. Ichthyology, ix. 67, 139, 140, 352, 391, 490, 507. Ichthyosauri, structure of, vii. 414. Ichthyosaurus, peculiarities of structure in the cervical region of, ix. 500. Ichthyosiagones, on the fossil genus, ix. 32. Iguanodon, discovery of some bones of the, V. 77. Impact and coUisiion, on, viii. 65. Imperial standard troy pound, x. 63. Impressions from feathers, process for taking, xii. 451. India, geology of, xii. 514 ; on the black cotton soil of, xii. 430 ; on the great basaltic district of, xii. 286. Indigo, analysis of, iv. 313 ; x. 324 ; ana- logy of alcohol and indigo, in their combination with sulphuric acid, x. 324 ; manufacture of, xii. 264. Indu<, on the geology of the banks of the, iv. 225. Infinite series, formulae for the summa- tion of, vi. 348 ; X. 121 ; xi. 41. Infusoria, collections of dried, ix. 90 ; tripoli wholly composed of infusorial exuviae, ix. 158, 392; fossil, used for food, X. 318. Ingleborough, on the trigonometrical height of, iv. 163. Inglis (Dr.), prize essay on iodine, vii. 441 ; viii. 12, 191 ; on the conducting power of iodine for electricity, ix. 450. Insects : — new British forms among the parasitic hymenopterous, i. 127 ; iii. 342 ; coleopterous, new genera and species of, iii. 151 ; metamorphosis of, iv. 381 ; circulation of blood in, vi. 300; new Dipterous insects, vi. 280, 447; compound eyes of, viii. 202; re- spiration of, ix. 532 ; voluntary sounds of, X. 327 ; temperature of, xi. 1 89. Integral calculus, viii. 515, 549; x. 210. Interference, on aberration in prismatic, ii. 191, 276. gaseous, ix. 324 ; interference of light, ix. 401 ; x. 364. Interpolation, M. Cauchy on, viii. 459. Intestinal worm, double-bodied, x. 253. Inulin, how obtained, x. 249. lodal, a new compound, x. 321. lodate of brucia, xi. 217 ; of cinchonia, xi. 217; of quina, xi. 218. Iodic acid, action of voltaic electricity on, X. 93. and morphia, xi. 219. aether, ii. 415. Iodide : — of iron, composition of, vii. 156; of lead, remarkable property of, ix. 405 ; of mercury, microscopical ex- amination of, ix. 1; of gold, ix. 266; of mercury, native, xi. 143; of silver, new property of, xii. 258; of platina and their compounds, iii. 384. LOND. AND EDIN. PIf ILOSOPHICAL \fAGAZINE, 1832 1838. 31 Iodides, metallic, action of chlorine on, iv. 467. Iodine, its action on starch, iv. 313; prize essay on, vii. 441; viii. ]2, 191; its con- ducting power for electricity, viii. 130, 400; microscopic history of, ix. 13; its action on organic salifiable bases, ix. 76 ; electrical conducting power of, ix. 450; protochloride and tercliloride of, X. 430; preparation of, x. 498; its action on the vegetable alkalis, x.500; and strychnia, x. .501 ; and brucia, xi. 216 ; and cinchonia, >i. 217 ; and co- deia, xi. 220; and morphia, xi. 218; and quina, xi. 218. lodous acid, iv. 392 ; method of prepa- ring, ix. 442. Ions, table of, v. 429. Ipoh or Upas poison, on tlie, xi. 193. Ireland, gold-workings of Wicklow, vii. 1 ; on the geological map of, vii. 480. Iridium, preparation of, v. 314; method of dissolving, xii. 141. — — , osmium, and platinum, some triple combinations of, ix. 232. Irkoutsk, on the mean temperature of, ii. 1. Iron : — separation of the oxides of, i. 86; action of sulphurous acid on the per- salls of, ii. 75 ; decomposition of cy- anuret of mercury by, vii. 78 ; iodide of, vii. 156; absence of magnetism in cast iron when in fusion, vii. 388 ; ma- nufacture of pig iron, vii. 406 ; on pro- tecting it from the action of salt-water, viii. 128; xi. 544; action of nitric acid upon, ix. 53, 57, 122, 259; periodide of, ix. 79 ; peculiar voltaic condition of, X.133, 172, 175, 267,276,425,428; xi. 329 ; its conversion into plumbafro, xi. 321 ; on the strength of hot and cold blast cast, xi. 556; Carron, Devon, North Welsh, Yorkshire, xi. 557 ; ela- stic forces of, xi. 558 ; its action at a high temperature on benzoic acid, xii. 460; on camphor, xii. 460; peculiar voltaic condition of, xii. 48 ; protoxide of, its action on protoxide of copper, xii. 299. and copper, alloys of, vi. 81 ; sul- phates of, action of oxalic action on, ix. 155. and zinc, sulphuret of, vii. 79. . beams, on the strength and best form of, i. 207. . cast, on the elastic power of, i. 74 ; the temperature of melting, i. 262; cohesion of, iii. 79 ; crystallized per- nitrate of, iii. 467. — ; — peroxide of, an antidote to arscnious acid, vi. 237. ' . pyrites, crystallized, artificial, X. 158. Isodynamic lines, on the direction of the, xi. 258. Isomorphnus substitution, on a case of, xii. 406, 407. Isothermal lines, on, i. 431. Ivory (J.) on the disturbing function, iii. 459; on the equilibrium of fluids, v. 454; astronomical refractions, vi. 142 ; on such functions as can be expressed by serieses of periodic terms, ix. 161 ; on ellipsoids, xii. 356. Ixalus Probaton, xi. 124. JB. on the attraction of an homoge- • neous ellip oid, vi. 203. J. H. N. on the juice of Eschscholtzia Californica, vi. 77. J. J., new method of taking deep sound- ings in the ocean, ix. 185. J. O. H., direct demonstration of the rule for the multiplication of iiegative signs, ix. 540. Jablonski on the chemical process of ve- getable life, xi. 532. Jacob (Dr.) on fossil Polyparia, vii. 483; on the mammary glands in the Ce- tacea, vii. 507. Jacobson (M.) on the physical and the- rapeutic properties of chromate of pot- ash, V. 238. "Jamaica, flora of," xii. 26.3. Jamesonite, analysis of, x. 237. Jerboas and Gerbillas, on the, xi. 394. Jerrard (G. B.) on solving equations of the fifth degree, vii. 202 ; on the trans- formation of equations, vii. 478 ; on the occurrence of the form ^, xii. 345. Jervine, a new vegetable base, xii. 29. Jloulouk, mean temperature of, i. 427. Jones (Capt.) on a cast of money current among the Africans, xi. 132. (T. W.) on the ova of women, vii. 209 ; on the retina and pigment of the eye of Sepia Loligo, viii. 1 ; on the first changes in the ova of the mam- mifera in consequence of impregnation, and origin of the chorion, xi. 93. Johnson (E. J.), magnetic experiments on an iron steam-\essel, viii. 547. (Dr. H.) on a newly observed pro- perty in plants, vi. 165 ; on the cause of motion in plants, vii. 357 ; on the divergence of plants, ix. 17. (G. H. S.), method of discovering the equations of caustics, vi. 37 2. Johnston ( Prof ) on iodic aether, ii. 4 1 5 ; on the dimorphism of baryto-calcite, vi. 1 ; on oxychloride of antimony, vii. 332 ; on the cause of certain optical properties of chabasie, ix. 166; on the 32 GENERAL INDEX OF VOLS. 1 1^2 OF THE iodides of gold, ix. '206; on baryto- calcite, x. 373 ; on the equivalents of potash, soda, and silver, xii. 324 ; on Hatchetine, xii. 338 ; on the compo- sition of Middletonite, xii. '261 ; on the dimorphism of chromate of lead, xii. 387 ; on the composition of Ozocerite, xii. 389 ; on an analogy in atomic con- stitution between the earthy carbonates and alkaline nitrates, xii. 480 ; compo- sition of retin asphalt, xii. 560. Johnstone (Dr.), notice of the late, xii. 277. Jupiter, Prof. Airy on the mass of, iii. 233; iv. 883. Jussieu (M.), notice of, x. 152, 470. Ken some curious facts respecting <» vision, V. 375. Kalium, crystallization of, v. 399. Ka":e (Prof.) on the analysis of some combinations of platina, ii. 197; on the interference of sound, vii. 301 ; on the salts of sulpho-methylic acid, vii. 397 ; on the protochlorides of platina and tin, vii. 399 ; on the action of hy- drochloric acid on certain sulphates, viii. 353 ; on the action of ammonia on the chlorides and oxides of mercury, viii. 495; on pyroxylic spirit, x. 45, 116; on the composition of thebaine, x. 387 ; on the protochloride and terchlo- ride of iodine, x, 430 ; on the powder formed by the action of water on white precipitate, xi. 428 ; on the action of ammonia on the protochloride of mer- cury, xi. 504 ; on the combinations derived from pyroacetic spirit, xii. 100, 107; on Dumasine, xii. 108. Kangaroo, notes on the, iv. 304; ix. 67, 388 ; on the generation of the, iv. 438 ; descriptions of the, vii. 66. Kater (Capt ), list of the papers contri- buted by him to the Philosophical Transactions, viii. 151. Keitli (Rev. P.) on living fabrics, ii. 8, 120; on the external structure of im- perfect plants, iv. 252 ; on the internal structure of plants, v. 112, ISl*, 284; on phytological errors and admoni- tions, v. 205 ; structure of animals, vi. 4, 90; classification of vegetables, vi. 379 ; X. 37, 108 ; on the conditions of germination, viii. 491. Kelland (P.) on the dispersion of light, viii. 429 ; on the transmission of light and heat in uncrystallized media, x. 336. Kelly (Dr.) on low fogs and stationary clouds, xii. 355. Kenrick ( Rev. J.) on the Greek tradi- tions of the deluge, iv. 414; v. 25. Kennedy (A.) on the economy of several species of hymenoplera, xii. 14. ■ (Dv.) on purulent ophthalmia, viii. 65. Kiernan (F.), Copley medal awarded to, x. 212. King (Capt. P. P.) notes on several ro- dent animals, ix. 68. (T. W.) on the tricuspid valve of the heart, vii. 207 ; on the safety-valve of the heart, ix. 525. Kinic acid and some kinates, on, ii. 479. Kinkajou, notice of the, x. 291. Knight (T. A.) on the powers of suction of the common leech, iii. 449 ; on the absorbent powers of the roots of trees, &c. X. 488 ; on the hereditary instinct- ive propensities of animals, xi. 96 ; on the supposed absorbent powers of the spongioles, xi. 534. ( Dr. W.) on the vibration of heated metals, iii. 239. Knox (G. J., and the Rev. T.) on fluo rine, i\. 107 ; xii. 105. (Rev. T.) on a new rain gauge, xi. 260. Koala, anatomy of the, x. 481. Koba and Kob of Buffbn, x. 303. Koene (M.) on a double salt of codeia and morphia, xi. 405. Kreosote, on, iv. 390. Kupferbliithe, crystalline form of, vii. 159. Kupfer-antimonglanz, on, vii. 422. Kupffer ( I'rof.) on some recent magnet- ical discoveries, i. 129; on the mean temperature of NicolaiefF, i. 132; on the mean temperature of Sevastopol, i. 259 ; Dr. Brewster's observations on, i. 260 ; on the mean temperature of Sitka in America, i. 427 ; on the temperature of Irkoutskjii. 1; meteor- ological observations made at St. Petersburgh, ii. 260. LACTIC acid, on, iv. 233; in sour- crout, xii. 142. Lagotis, on, iii. 149. Ivagrange's principle of virtual velocities, remarks on, ii. 16. Lamellibranchiate conchiferous animals, anatouy of the, ix. 224. Laminaria di^ Mayo and Sligo, on the geology of, ii. 149. Mease (Dr.) on the dry rot of ships, xi. 192. ^Measures of Covent Garden, dimensions of, i, 472 ; ii. 405, 482. Meconine, on, ii. 156. ■^•••rjM Medal-ruling, on an improvettieM^'ii, ii. 288. ■■•- Medical science, grants of money for the advancement of, ix. 314. Medusae, luminous, xii, 213. Meeson (H. A.) on the detection of opium, vi, 158. • » ■ '■■■' Megatherium, discovcW In Bttenos Ayres of three skeletons oi^ i. 233. Mellltic acid, x, 159. Melloni (M,) on the transmission of ca- lorific rays throngh diathermal bodies, Vii. 475 ; theory of, on, viii. 23, 109,186, 190, 246. LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 3? Melolonthidte, a new genus of, vii. 224. Mercury, transit of, observed at Geneva, i. 246 ; transit on May 5th, 1832, i. 322 ; observation at Utrecht of the transit of, ii. 379. Mercury, cyanuret of, its decomposition by iron, vii. 78 ; action of ammonia on , the chlorides and oxides of, viii. 495 ; . Yibibroraide of, ix. 148 ; iodide of, opti- cal properties of, ix. 1 ; native, locality of, ix. 155 ; xi. 143 ; compound of al- bumen and bichloride of, x. 420 ; analy- sis of double salts of, xii. 235 ; tritio- dide of, xii. 27. Mersey and Dee, a survey of, vii. 487. Mesityl, oxide of, xii. 100. Metallic oxides, separation of, vi. 234. Metalliferous veins, questions on, i. 469 ; on the electro-magnetism of, iii. 16, 17. — — deposits, on the relative position with regard to the unstratified rocks, i. 225. Metals, fusing points of, i. 202 ; on the vibratiou of heated, iii. 321; iv. 15, 182; vi. 85; electrical relations of, vi. 300 ; action of in determining gaseous combination, vi. 354 ; corrosion of by sea- water, on the prevention of, vii. 389 ; magnetic relations of, viii. 179; their reduction by electricity, x. 154 ; action of nitric acid on, xi. 554 ; colours of, xii. 298. Metanaphtalene, new carburets of, xi. . 404. Meteor, seen June 29th, 1832, Mr. Ed- .qiinond's notice of, i. 306; Mr. Pri- deaux's, i. 307 ; extraordinary, seen at , , Malvern, iii. 37. Meteoric stones, on, ix. 429 ; in Brazil, xii. 462. Meteorite, in Moravia, vi. 159 ; in India, vi. 398. Meteors observed in India, ix. 74 ; of Nov. 12th, 1837, xii. 85. Meteorological deductions made at Port Louis in 1833, 1834, and 1835, xi. 97. -- — journal kept at Penzance, ii. 159. observations, ix. 79, 159, 239, 319, 399, 544; x. 79, 159, 239, 327, 423, 503 ; xi. 143, 223, 327, 407, 487, 567 ; taken at Bermuda in 1836, xi. 449. phaenomena, notice of, iv. 103; cause of, iv. 233. , Meteorological Society, xii. 291, 601. table, by Mr. Thompson, Mr. Giddy, and Mr. Veall, i. 88, 168, 248, 328, 408, 475 ; U. 80, (60, 240, 320, 408, 484 ; iii. 80, 159, ^40, 320, 400, 468 ; iv. 80. 100, 240, 320, 400, 468 ; v. 80' 160, 239, 320, 400, 468; vi. 80, 160, 240, 320, 400, 468; vii. 80, 160, 240, 633, 432, 542; viii. 88, 176, 264, 352, 448, 593; ix. 80, 160, 240, 320, 400, 545 ; X. 80, 160, 240, 328, 424, 504 ; xi. 144, 224, 328, 408, 488, 568 ; xii. 144, 224, 304, 384, 463, 544. Meteorology, viii. 67, 78, 187, 236, 263, 351, 447, 592 ; on the progress of, iii. 131 ; of Dukhun, vi. 59 ; remarks on the year 1834 at Carlisle, vi. 427 ; on certain points in, vii. 355 ; observa- tions, xii. 143, 223, 303, 382, 463, 543 ; low temperature of Jan. 1838, xii. 302 ; observations made at Ber- muda in 1836-37, xii. 42; observa- tions made in Colombia, between 1820 and 1830, xii. 148 ; meteorology of Te- neriife, xii. 291 ; description of a new barometer, xii. 204 ; si)ecimen of a thermometrical diary, xii. 498. Methylene, on, vii. 427, 538 ; new com- binations of, ix. 77. Meyeu (J.) on the progress of vegetable physiology, xi. 381, 435, 524 ; xii. 53 ; on the structure of the glands on the leaves of the Labiatae, xi. 531. Michell on stratification, i. 268. Micrometer, on a species of natural, &c. ii, 64. Microscope, achromatic viii. 70 ; polari- zing, ix. 288 ; a new object for the, iii. 318 ; test objects for, ii. 335 ; solar and oxy-hydrogen, x. 184, 219. Microscopic chemistry, on, ix. 2, 10. objects, dried, ix. 90. Middletonite, on, xii. 261. Milk, sugar of, on its fermentation, xii. 139. Miller (Prof.) on the effect of light on the spectrum passed through coloured gases, ii. 381 ; on the forms of sul- phuret of nickel, &c. vi. 104 ; on the measurement of the axes of optical elasticity of certain crystals, viii. 431. Mineral veins, viii. 229 ; ix. 8, 387 ; x. 394 ; method of imitating, ix. 229 ; on the phajnomena of, xii. 125; on the process by which thev have been filled, xi. 203. Mineralogy: — "Allan's Manual" of, vi. 53 ; mineralogical notices, vi. 76 ; ana- lysis of nadelerz, vi. 77 ; new mineral, vi. 133 ; analyses of osmiridium and allanite, vi. 238 ; new locality of plen- akite, vii. 239; rhodizite, vii. 431 ; ga- dolinite, vii. 430 ; Wolfram, ^ii. 335 ; analysis of plenakite, vii. 540 ; on sym- boUc notation as apphed to, \1ii. 101 ; '* Breithaupt's Mineralog}-," viii. 173; 38 GENERAL INDEX OF VOLS. 1 — 12 OP THE on thulite and stromite, viii. 1G9 ; cule- brite, viii. 261 ; Riolite and Herrerite, viii. 261 ; antimonial copper, ix. 149 ; doniura, a new metal, ix. 156, 255 ; change in the chemical chai*acter of minerals induced by galvanism, ix. 228 ; artificial crystals and minerals, ix. 229, 537 ; composition of plagionite, ix. 232 ; new mode of analysis of closely aggre- gated minerals, ix. 76 ; Zeagonite, Gis- mondin, Abrazite, Aricite and Pliil- lipsite, X. 170; Murchisonite, Moon- stone, and the iridescent felspar from Fredericksvarn, X. 170; analysis of tin pyrites, Tennantite, Jamesonite, Augite and Amphibole, x. 236 ; on the inter- section of crystalline minerals, x. 278 ; on the identity of Biotine and Anor- thite, and on a new crystal of quartz, X. 368 ; crystallographical identity of phacoUte and the Irish bipyramidal levyne with chabasie, xi. 12 ; on mu- rio-carbonate, and native muriate of lead, xi. 175; on the crystalline form of pyrosmalite, xi. 261 ; account of Edwardsite, xi. 402. Minerals of the North of Ireland, iii. 83. organic forms of, x. 318. Mines, variation of the quantity of water in, i. 288 ; in the Savana region, discovery and progress of the, xi. 22 ; on their temperature in Cornwall and Devonshire, xi. 520. Minium, experiments on, ii. 402 ; iii. 125. Mirage, pha;noraenon resembling, seen in the Regent's Park, vii. 77 ; as seen in Cornwall, viii. 169. Mirror, account of a curious Chinese, i. 438. Mitchell (Dr.) on certain strata in Buck- inghamshire, iv. 148 ; on the Reculver cliff, iv. 149 ; on the chalk and flint of Yorkshire, vi. 313; on the beds imme- diately above the chalk near London, ix. 356 ; on a well at Beaumont Green, Hereford, xi. 215. Mitchell's (Prof.) method of preparing carbonic oxide. Dr. Gale on, vi. 232. Mitscherlich (E.) on nitro-benzide and sulpho-benzide, viii. 257; on the for- mation of aether, viii. 258. Mitranaj, observations on the different species of, ix. 137- Mohl (M.) on the symmetry of vegetables, xi. 383 ; on the validity of Ehrenberg's character for distinguishing animals and vegetables, xi. 387. Molecular action, x. 320, 355, MoUusca, on marine testaceous, 1.^384. Monetary calculation, a decimal system of, vi. 441. Monkey, peculiar species of, iv. 61 ; ex. 73. Monkeys, some remarks on, ix. 303. Mont Blanc, on the varying colours of, at sunset, i. 335 ; on an optical phae- nomenon observed at, xii. 122. Monticelli (Sig.) on the structure of lava, i. 228. Moon, on the theory of the, iv. 218, 220. Moore (Mr.) on the earthquake in Svria, xi. 204. Mora tree of British Guiana, xii. 532. Morgan (A. De) on the relative signs of coordinates, ix. 249. Morichini (Prof.), notice of, xii. 280. Mornay (M.) on the inflammable milk of Euphorbia phosphprescens, xi. 530. Morphia, new process for obtaining, i. 327 ; in poppy seeds, iv. 236. "^^ and quina, new test for, vi. 158. and iodine, xi. 218. and iodic acid, xi. 219. Morren (M.) on the respiration of plants, xi. 537. Morris (J.) on the strata usually termed plastic clay, xi. 104. Mortality, influence of high and low prices on, v. 278. Moschus, two new species of, ix. 515. Moseley (Rev. H.) on a new principle in statics, iii. 285 ; on the theory of re- sistances in statics, iii. 431 ; principle of least pressure, remarkson,iv. 89, 271; V. 95 ; Mr. Horner's considerations re- lative to, V. 188 ; his replies to Mr. Earn* Shaw, iv. 194,420. : Mosses, on, iv. 254 ; of Upper Assam, xii. 532 ; on the existence of storaata in, xii. 533. Mossotti (M.) on molecular action, x. 320. Motion, transmitted, analytical deter- mination of the laws of, vi. 267. Mould, formation of, xii. 89. Mount Etna, eruption in 1536, vi. 299. Mountain chains of Europe and Asia, on the, iv. 1. Mountains, on the ascent of, x. 261. Mudge (Capt.) on the ossiferous cavern of Yealm Bridge, viii. 579. Mulder (M.) on the red and white oxide of phosphorus, x. 499 ; on the prepara- tion of sulphuret of carbon, xi. 221. Miiller (Prof.) on the existence of four distinct hearts in certain amphibious animals, iii. 41 ; account of the reflex function of the spinal marrow, x. 51, 124, 187, 378. Miilins (F. W.) on an improved mag- neto-electrical machine, ix. 120; on the construction of voltaic batteries, ix. LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 — 1838. 39 382 ; X. 63 ; on magneto-electrical ma- chines, in reply to Prof. Ritchie, x. 12 ; on the action of electricity in voltaic combinations, x. 281. Mummy cloth of Egypt, on the, v. 355. Mmal circles, Greenwich, v. 305; Cape of Good Hope, v. 309. Murchison (R. I.) on the structure of the Cotteswold and Cleveland hills, i. 221 ; on the sedimentary deposits of Shrop- sliire, Ilerefordsliire, &c., iii. 224 ; on freshwater limestone near Shrewsbury, iv. 159 ; on the old red sandstone of parts of Wales, &c., iv. 228 ; on the transition rocks of Shropshire, &c., iv. 370, 450 ; on the gravel and alluvial deposits of Hereford, Salop, and Wor- cester, V. 217 ; on certain trap rocks in Salop, &c., v. 225, 292 ; on an out- lying basin of lias on the borders of Salop and Cheshire, with an account of the lower lias between Gloucester and Worcester, vi. 314 ; general view of the new red sandstone series in the counties of Salop, Stafford, Worcester, and Gloucester, vi. 315 ; on certain coal tracts in Salop, Worcestershire, and N. Gloucestershire, vi. 376 ; on the Silurian system of rocks, vii. 46, 483 ; on the geology of North Salop and Staffordshire, vii. 415 ; on the dis- covery of fossil fishes in the new red .sandstone of Tyrone, viii. 72 ; on the geological structure of Pembrokeshire, viii. 561 ; on the gravel and alluvia of South Wales and Siluria, viii. 566 ; on the fossil genera Pseudaramonites and Ichthyosiagonites of the Solenhofen limestone, ix. 32 ; on the Silurian and other rocks of the Dudley and Wolver- hampton coal-field, ix. 489 ; on a raised beach in Barnstaple Bay, x. 477 ; on the physical structure of Devonshire, xi. 311 ; on the upper formations of the new red system, xi. 318. Muriate of ammonia, its action on*cei> tain sulphates, vi. 235. - , . > ' Muriatic acid in fluor spar, v. 78; on the immersion of copper in, vi. 444 ; method of testing its presence in hy- drocyanic acid, vii. 400. Murio-carbonate and native muriate of lead, on, xi. 175. > Murphy (Rev. R.) on the roots of equa- tions, ii. 60, 220 ; on the real functions of imaginary quantities, ii. 287 ; On electrical influence, ii. 350 ; on the in- verse method of definite integrals, iii. 461 ; on a new theorem in analysis, 1. 28 ; on rectangular forces, x. 105 ; on the theory of analytipal operations, x. 219 ; on an error o£ M* I'ourier in his " Analyse des Equations," xi. 38 ; on the roots of equations, xi. 92. Murray (Sir J.) on the influence of arti- ficial rarefaction in some diseases, and the effects of its condensation in others, viii. 62. Mus, new species of, xii. 443. Musci, new genus of, iii. 30. Muscular effort required to ascend planes of different inclinations, x. 261 ; mus- cular fibre of animal and organic life, X. 377 ; xi. 194. Mushet (D.) on the practicability of alloying iron and copper, vi. 81 ; on the fusion and appearance of refined and unrefined copper, vi. 324 ; on the immersion of copper in muriatic acid, as a test of its dm-ability, vi. 444. Mushrooms, on, iv. 258 ; their action on atmospheric air, viii. 82. Myrmecobius, characters of, ix. 520; on differences existing between two spe- cimens of, xi. 200. NADELERZ, analysis of, vi. 77. Naphtha, on a fluid obtained in the manufacture of, vii. 395 ; analysis of, vii. 429. Naples, influence of the climate of, on vegetation, iv. 274. Narcissinese, Haworth on the, i. 275. Nautilus, pearly, on the theory of the ac- tion of the siphuncle in the, xii. 503 ; the paper nautilus, xii. 601. Nebula;, observations of, iv. 125. Necker (Prof.) on optical phenomena seen in Switzerland, &c., i. 329 ; on the relative position of metalUc deposits and unstratified rocks, i. 225. Needles rendered magnetic by the nerves, xii. 223. Negro, on the brain of the, ix. 527. Negro's (Sig. Dal.) magneto-electric ex- periments, i. 45. Negros, Asiatic, natural history of the, i. 466. Nelson (Lieut.) on the geology of the Bermudas, v. 222. Nephrodium rigidum, viii. 255. Nervous and muscular systems in ani- mals, on the , iii. 40. Newbold (Capt.) on the Ipoh or Upas poison, xi. 193; on the black cotton soil of India, xii. 430. Newcastle (in Australia), geology of the south-cast coast of, i. 92. Newman (E.) on the metamorphosis of insects, iv. 381. Newport (G.) on the nervous system of Sphinx ligustri,vi. 55; on the respiration of insects, ix. 532 ; Royal medal award- ed to, X. 214 ; on the temperature of 40 GENERAL INDEX OF VOLS. 1 12 OF THE insects, and its connexion with respi- ration and circulation, xi. 189. Newton's rin8:s, on the phsenomena of, i. 400; ii/20; x. 183 ; xii. 28, 485; on coloured bands observed in ex- amining, vii. 363, 474. Principia, inquiry relative to Dr. Pemberton's translation of, viii. 441 ; theory of natural colours, on, viii. 468. Newton and Flamsteed, viii. 139, 211, 218, 225. (Sir I.) on the manuscript of, xi. 138. Niagara, on the Falls of, v. 11. Nicholson (P.) remarks on his rule for the construction of the oblique arch, X. 167. Nickel, form of sulphuretof, vi. 104 ; se- paration of zinc from, viii. 80. and cobalt incapable of being ren- dered inactive, xi. 547. Nicol's (Mr.) polarizing eye-piece, on, iv. 289. Nicol (W.), structure of Coniferae, vii. 490. Nicolaieff, on the mean temperature of, i. 132. Nicotin, Prof. Davy, on, i. 393. Nidalia, a new genus of corals, vii. 331. Nile, plan for exploring the western branch of the, xii. 543. Nimmo (A.), notice of, iv. 446. Nitrate of carbohydrogen, viii. 85. Nitre, its formation in extract of quassia, xii. 140 ; new property of, xii. 145. Nitric acid, its action upon iron, ix. 53, 259 ; X. 133, 267, 276, 425 ; xii. 49 ; on the causes of the neutrality of iron in, X. 172 ; its action on certain metals, xi. 554 ; its action on bismuth, xii. 305. Nitro-benzide and sulpho-benzide, vii. 257. Nitrogen, iodide of, viii. 12. Nitrosulphuric acid, x. 489. Nixon (J.) on the measurement of the instrumental error of his horizon- sector, i. 98; ii. 327; on a repeating circle, i. 340 ; on the trigonometrical height of Ingleborough, iv. 163; vi. 248, 429 ; on the tides in the Bay of Morecambe, v. 264 ; verification of Capt. Lloyd's levelling instrument, vii. 364 ; table of observed terrestrial re- fractions, viii. 479 ; heights of Whern- side, Great Whernside, Rumbles Moor, Pendle Hill, and Boulsworth, ix. 96. Noad (H. M.) on the peculiar voltaic condition of iron, x. 276 ; of iron and bismuth, xii. 48 ; on the hydrates of barvta and strontia, xi. 301. Nobili (M.) notice of tlie life and con- tributions to science of, ix. 234. Nordenskiold on Phenakite, v. 102. Norfolk, geology of, vii. 171, 274, 353, 370, 463. Normandy, geological character of the coast of, xi. 210. North magnetic pole, Commander Ross on the position of, iv. 222. North-west passage, discovery of the, xii. 542. Notation, on chemical, ii. 309. symbolic, as appUed to mineralogy, viii. 101. Nycteribia, the genus, vi. 392. Numbers, theory of, new demonstration of an original proposition in, xi. 456. Nux vomica, new acid in, iv. 153. OBJECT-GLASS, double achromatic, vii. 161. Object-glasses, on a new species of co- loured fringes in, i. 19. Observatory, magnetical, at DubUn, xii. 119. Occultations, lunar, i. 87, 167, 247, 327, 405, 473. Ocean, method of ascertaining the depth of, iii. 82; ix. 185; remarks on, iii. 352 ; on the phosphorescence of the, xii. 211. Oceans, Pacific and Indian, areas of ele- vation and subsidence in the, xi. 307. Octopus, nondescript species of, ix. 301. Odynerus quadratus and 0. bidens, ha- bits of, xii. 1 7. (Enanthic acid, x. 417, 422. (Enanthic aether, x. 418. Ogilby (W.) on the Cynictis, iii. 67 ; on several Marsupialia, ix. 70 ; on the op- posable power of the thumb in certain mammals, and on the natural affinities which subsist between the Bimana, Quadrumana and Pedimana, ix. 302 ; on the Chironectes Yapock, ix. 510; on some hollow-horned Ruminants, xi. 124 ; arrangements of the Ruminantia, xi. 469 ; on the quadrupeds of Austra- lia, xii. 95. Oil of bitter almonds, composition of, iii. 389 ; iv. 70 ; of cinnamon, vii. 74 ; of turpentine, hydrate of, vii, 537 ; on the phainomena of drops of, floating on water, viii. 288; volatile, ix. 155; of caoutchouc, ix. 321, 479 ; aethereal, of wine, X. 417; oil which accompanies pyroxvlic Sf>irit, x. 48 ; empyreumatic, xii. 101. Oils, action of sulphuric acid on, ix. 153. Ol'oers (Dr.) on the return of Halley's comet, vi. 45 ; method of determining LOND. AND KDIN. PHILOSOPHICAL MAGAZINE, 1832 — 1838. 41 the orbits of comets, on, vii. 7, 123, 203, 280. Oleon, V. 153. Olivile, analysis of, iii. 381. Oolitic formations of Gloucestershire, sur- vey of, ii. 300. Ophthalmia, purulent, viii. 65. Opium, substances contained in, ii. 153 ; new substance in, iv. 77 ; detection of, vi. 158 ; new alkali in, viii. 44-1 ; che- mical history of, xi. 335. Optical experiment, viii. 168; optical structure of tlie crystalline lenses of animals, viii. 193 ; illusion, on a new instrument of, iv. 36 ; pha^nomena seen in Switzerland, i. 329 ; xii. 122 ; phffinoraenon, peculiar, v. 373. properties of oxalate of chromium and potash, vii. 436 ; science, facts re- lating to, iv. 112, 289 ; ix. 1, 401 ; pro- perties of chabasie, ix. 166; phaeno- mena of certain crystals, ix. 288 ; x. 218 ; theory of crystals, Fresnel's ana- lytical reduction of, xi. 462. Optics: — on the undulations excited in the retina by luminous points and lines, i. 169 ; on a new photometer by comparison, i. 174; on the action of the brain on vision, i. 249. and perspective, new instrument as a means of instruction in, iii. 464. Orang Outang, frequent deficiency of the ungueal phalanx in the, vii. 72. Orang-outangs, specific distinctions of the, X. 295. Organ, enharmonic, vii. 366. Organic acids, constitution of, xii. 381 ; on a new, xi. 564. chemistry, researches in,x. 45, 116. compounds, a new force acting in the combinations of, x. 490; method of analvsing, xii. 31, 232. remains, vii. 81, 174, 182, 221, 278, 374; viii. 30, 561, 576; ix. 349, 386, 462,490,496; x. 4, 137,402. Ornithology, ix. 66, 138, 227, 503, 511 ; new species of Ortyx, x. 287 ; xii. 527; two new species of birds from New South Wales, x. 287, 306 ; rare birds in the vicinity of Scarborough, x. 287 ; three-quarter-bred pheasants, x. 292 ; birds from Swan River, x. 293 ; new genus in the group of wTcns, x. 295 ; list of birds noticed at Smyrna in the winter of 1835-6, x. 301 ; habits of the vulture, X. 479; ground finches, xii. 215 ; new species of parrot, xii. 215 ; new raptorial birds, xii. 215 ; new Fis- sirostal birds, xii. 444 ; habits of the Vultur aura, xii. 447 ; Rhea Darwinii, xii. 450 ; simple process for taking im- pressions from feathers, xii. 451 ; Humming birds, xii. 526 ; British wag- tail (Motacilla Yarrellii,) xii. 596. Ornithorhynchus paradoxus, on the mam- mary glands of the, i. 384 ; iii. 60, 301 ; abdominal glands of, iv. 54 ; on the young of, v. 235 ; the ova of, vi. 60 ; natural history and habits of, vi. 307. Orobanche, on the aflSnities of, xi. 409. Osborne (Dr.) on the etFects of cold on the himian body, and on a mode of measuring refrigeration, viii. 59. Osier (Mr.) on a new registering anemo- meter and rain gauge, xi. 476. Osmia biconiis, and 0. spinulosa, xii. 18. Osmium, its separation from iridium, iv. 155 ; preparation of, v. 314 ; iridium, and platinum, triple combinations of, ix. 232. Osmiridium, on, v. 101 ; analysis of, vi. 238. Osteology, human, vi. 57; of the orang and chimpanzee, vi. 457. Ostrogradsky (M.) on a singular case of the equilibrium of fluids, remarks on, xii. 385. Otter, Irish, vi. 229 ; osteology of the, ix. 512. Otus brachyotus, habits of, xii. 104. Oude, royal observatory of, iv. 158. Ovaries in the human species, on the, vii. 209. Owen (R.) on the mammary glands of the Ornithorj'nchus, iii. 14 ; reply to, iv. 54 ; anatomy of the Terebratula, &c., iv. 302 ; on the kangaroo, iv. 304, 438 ; on the crania of the lion and tiger, iv. 454 ; on the anatomy of the Touraco, iv. 456 ; anatomy of the Ca- lyptraeida;, v. 72 ; on the structure of the heart of the Perennibranchiate Am- phibia, V. 150; on the young and ova of the Ornithorhynchus paradoxus, v. 235 ; vi. 60 ; description of a recent Clavagella, vi. 230 ; on a new species of Entozoon, vi. 452; anatomy of Linguatula Taenioides, vi. 450 ; osteo- logy of the orang and chimpanzee, vi. 457; dissection of a Dasyurus, vii. 154 ; anatomy of the Pelican, vii. 154 ; on some Cephalopoda, ix. 298 ; on the morbid appearances observed in dis- secting the chimpanzee, ix. 388 ; on the anatomy of the wombat, ix. 504 ; on the brain of marsupial animals, x. 222 ; on the specific distinctions of the orangs, x. 295 ; description of two En- tozoa in the stomach of the tiger, xi. 128; on the cranium of the Toxodoi\ 42 GfiNEKAL INDEX OF VOLS. 1 12 OF THE platensis, xi. 205 ; the Wollastou me- dal awarded to, xii. 433 ; on the dislo- cation of the tail in Ichthyosauri, xii. 590; on the cranium of an orang outang, xii. 599 ; examination of a foetal kangaroo, xii. 600. Owl, short-eared, habits of, xii. 104. Oxacids, their action on pyroxylic spirit, vi'. 538 ; viii. 85. Oxalhydric acid, iv. 74 ; xi. 142. OxaUc acid, action of chloride of sodium upon, V. 445 ; its action on the sul- phates of iron and copper, ix. 155. Oxalo-nitrate of lead, xii. 459. Oxford, meeting of the British Associa- tion at, i. 77. Oxide of chromium, crystallized, viii. 175; of lead, on the solubility of, in water, xi. 221 ; of silver and oxide of lead, definite coml)ination of, xii. 217. Oxides :— carbonic, on Prof. Mitchell's method of preparing, vi. 232 ; metal- lic, separation of, vi. 234. and salts, their solubility in mu- riate and nitrate of ammonia, x. 95, 178, 333. Oxychloride of antimony, vii. 332. Oxygen in the atmosphere, on the quan- tity of, xii. 397. Oxy-'hydrogen jet, on a new, ii. 57. Ozocerite, composition of, xii. 389. " T3 ^•''' ^^ chemical decomposition Jl • effected by the magneto-elec- tric current, i, 161 ; on magneto-electri- city and electro-magnetism, iii. 18. Painting in enamel, art of, x. 442 ; on glass, on the art of, ix. 456. Palaeoniscus Egertonii, xii. 86. Palaeontology, new discoveries in, ix. 158, 392; X. 318. Palms, internal structure of the w^ood of, xi. 553. PalodeVaca, pericarp and nuts of, vii. 501. Paper, hydrographic, iii. 466 ; made from turf, vii. 401. Papuans, on the history of the, i. 466. Parabola, on a property of the, ix. 100 ; x. 32 ; xi. 302. Parabolic curves, the arcs of, v. 455. Paraffin and eupion, on, i. 402 ; analysis of, ii. 78. Parallelogram of forces, demonstration of the, V. 39. Paramorphia, discovery of poisonous pro- perties of, xi. 335. Parilline and parillinic acid, analysis of, V. 465. Parish (W.) on the effects of the earth- quake waves on the coasts of the Pa- cific, viii. 181. Parrot, new species of, xii. 215. Patents, list of new, i. 167 ; on the law of, i. 212. Patent laws, proposed modification of, iii. 316. Payen (M.) on the action of tannin, &c. on the roots of plants, v. 157 ; on a new acetate of lead, xii. 133. Peafowl, habits of the, vii. 228. Pearson's (Dr.) " Introduction to Prac- tical Astronomy," i. 370, 450. Pekin, magnetical and meteorological ob- servations at, i. 130. PeUcan, anatomy of the, vii. 154, 223. Peligot (M.) on camphor, x. 420 ; on carbovinate of potash, xi. 320 ; on a new organic acid, xi. 564. Pelletier (M.) on the action of iodine on organic salifiable bases, ix. 76 ; x. 500 ; xi. 216 ; on the elementary composi- tion of paramorphia, xi. 335. Pelouze (M.) on an athereal oil of wine, X. 417 ; on the action of presence, x. 489 ; on the products of the decompo- sition of cyanogen in water, xii. 339. Peraberton's (Dr.) translation of New- ton's Principia, inquiry relative to, viii. 441. Pembrokeshire, geology of, viii. 561, 567, Pemphredon lugubris, P. Morio, and P. unicolor, xii. 17. Pendulum, Mr. Daily on the, i. 379 ; in- variable experiments with, i. 420 ; ii. 458 ; experiments on tlie seconds, ii. 244, 344, 434 ; Captain Forster's ex- periments on the, iv. 230. Penguin, habits of, v. 231 ; anatomical description of, vii. 519. Penrhyn, on the granite found near, ii. 321, 322. slate quarries, on a trap dyke in the, xi. 103. Pentacrinus Europseus, vii. 495. Perameles, on a new species of the genus, xi. 198. Per-iodic acid, properties of, x. 325. Periodide of iron, ix. 79. Peroxide of iron, separation of, from pro- toxide of manganese, from protoxides of iron, from oxides of cobalt and nickel, i. 85 ; as an antidote to arse- nious acid, vi. 237. of bismuth, iii. 387. of mercury, action of ammonia on, xi. 504. Persian Gulf, on the former extent of, iv. 107 ; V. 244 ; viii. 506 ; ix. 34 ; xi. 66 ; advance of land in, vi. 401 ; vii. 41, 192, 250. Perspective, a new instrument as a means of instruction in, iii. 464. Petersburgh, St., meteorological observa- tions made at, ii. 260. LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 43 Petherick (T.) on the electro-magnetism of metalliferous veins of a copper mine in Ireland, iii. 16. Phainoganjous plants, on the develop- ment of the organization in, xii. 172, 241, 292. Phacolite and levyne, identity of with chabasie, xi. 12. Phenakite, a new mineral, v. 102. Philip (Dr. A. P. W.) on the nervous and muscular systems in animals, iii. 40; on the natiure of sleep, iii. 143; on death, iv. 360 ; on the powers on which the functions of Ufe depend, ix. 430. Phillips (Prof. J.) on the lower coal se- ries of Yorkshire, i. 349 ; on a modi- fication of the electrophorus, ii. 363 ; on the ancient forests of Ilolderness, iv. 282 ; on subterranean temperature, v. 446 ; on a newly discovered tertiary deposit in Yorkshire, vii. 486 ; on the geology of Manchester, ix. 157. (R.) on the action of suli)hurous acid on the persalts of iron, ii. 75 ; on Dr. Priestley's notice of caoutchouc, ii. 77 ; experiments on platina, ii. 94 ; on the analysis of some combinations of platina, ii. 197 ; on minium, iii. 125 ; analysis of two sulphureous springs near Weymouth, iii. 158 ; on the use of chemical symbols, iii. 443 ; iv. 246 ; replies to, iv. 41, 106, 402, 464; on isomorphism, xii. 407 ; on the consti- tution of the true red oxide of lead, iii. 128 ; on the composition of phosphu- retted hydrogen, iii. 308 ; review of Rees's translation of Berzelius on the analysis of inorganic bodies, iii. 463 ; on the action of oxacids on pyroxylic spirit, viii. 85 ; on the quantity of water contained in crystaUized barytes and strontia, vi. 52; on the combination of water with salts, xi. 388 ; on the solubility of arsenious acid, xi. 487 note ; on the action of cold air in main- taining heat, xi. 407 ; letter to, from Mr. R. Addams on the same subject, xi, 446 ; on a new acetate of lead, xii. 134. Philology, importance of the languages of uncivilized nations, vii. 27, 94. Philosophical Society of Cambridge, iv. 66. Phloridzine, viii. 444 ; properties of, xi. 337. Phosphorescence of the ocean, xii. 211. Phosphorus, red oxide of, ii. 78 ; hydrate of, ii. 79 ; red and white oxide of, x. 499 ; arsenic in, vii. 331. Phosphovinic acid, and T)ho8phovinates, ii. 73. Phosphuret of azote, vii. 158. Phosphurets, metallic, iii. 310. Phosphuretted hvdrogen, composition of, iii. 308; v. 401. Photometer, on the method of computing the results of experiments with the, xii. 484. Photometry, v. 327 ; by comparison, on a new instrument for, i. 174 ; its appli- cation to the undulatory theory of light, v. 439. Phrenology, early anticipation of, iii. 308. Physaha pelagica, xii. 528. Physeter macrocephalus, xi. 196. Physics, on M. Mossotti's theory of, xi. 496. Physiology of the voice, ix. 201, 269, 342 ; on the motion of the arm, ix. 411 ; vegetable, ix. 372 ; xi, 156, 381, 435; xii. 53; of respiration in insects, ix. 533. Phytochemistry, progress of, x. 247 ; xi. 333. Phytological errors and admonitions, v. 205. Pingel (Dr.) on the gradual sinking of the west coast of Greenland, viii. 73. Pinus, descriptions of two species of, viii. 255 ; sylvestris, starch in the bark of, x. 249. Piperine, M. Pelletier on, iii. 313. Placunanomia, on the genus, iv. 455. Plagionite, composition of, ix. 232. Planche (M.) on the formation of nitre in extract of quassia, xii. 140. Plants, on the external structure of im- perfect, iv. 252 ; on the internal struc- ture of, V. 112, 181, 284 ; action of tannin on the roots of, v. 157; on a property in, analogous to the irritabi- lity of animals, vi. 165; divergence the cause of motion in, vii. 357 ; ix, 1 7 ; development and growth of the stems and leaves of, ix. 372 ; on structure in the ashes of,xi. 13, 413 ; chemistry of, xi. 156; siliceous contents of, xi.339; on the symmetry, arrangement, and characteristics of the natiu-e of, xi. 383; on the combination, structure, and contents of the cells of, xi. 435 ; action of solar light on, xi. 537 ; on the conservation of, xi. 566 ; fossil, ii. 475. Plastic clay, on the, xi. 104. Platina, spongy, method of obtaining, x. 154 ; and hydrogen, compound of, v. 155 ; experiments on, ii. 94 ; ix. 544; analysis of some combinations of, ii. 197 ; the iodides of, and their com- pounds, iii. 384 ; found in galena, iv. 319 ; on some new combinations of, v. F2 44 GENERAL INDEX OF VOLS. 1 12 OF THE 150 ; discovery of in France, v. 158 ; ix. 232, 314. Platinum, muriate of, action of light in determining its precipitation by lime- water, i. 58. Platypus, on the habits of the, ii. 71. Plenakite, new locality of, vii. 239 ; ana- lysis of, vii. 540. Plombgomme, analysis of, ix. 75. Plumbago, conversion of iron into, xi. 321. Poggendorff (M.) on certain discoveries by Prof. Faraday, vii. 421. Poggiale, (M.) on the active principle of sarsaparilla, v. 463. Poison, the Ipoh or Upas, used by the Jacoons, xi. 193. Poisson's (M.) capillary theory on, viii. 89. Polariscope, simple, viii. 70. Polarity, magnetic in metallic bodies, i.31. Polarization :— of heat, vi. 134, 205, 284, 366 ; vii. 349 ; cause of elliptical, xii. 10 ; in the crystalline lens after death, xii. 22 ; of heat by tourmaline and by refraction, xii. 549 ; by reflection, xii. 553. Polarizing microscope, ix. 288. Polygalic acid, xi. 561 ; modified, xi. 562. Polyhetkon, solid, on certain relations in a, xii. 323. Polypi, on the structure and functions of, iv. 365 ; on the structure of the higher forms of, xi. 189. Polyspherite, v. 78. Pond (J.) on the new zenith telescope at the Royal Observatory, iv. 367 ; notice of, X. 146. Pons (J. L.), notice of the death of, i. 239. Population of Great Britain, comparative account of the, i. 213, 361. Porcelain earth, composition and origin of, X. 348. Portlock (Capt.) on the occurrence of Anatifa vitrea on the Irish coast, xi. 135 ; on the habits of the short-eared owl, xii. 104. Port Louis, meteorological deductions made at, xi. 97. Potash, preparation of chlorate of, i. 164 ; preparation of caustic, i. 244 ; car- bonate of, from plants, iii. 72 ; action of lime on solutions of, iii. 314; per- manganesiate of, iv. 155 ; chromate of, physical and therapeutic properties of, V 238 ; crystallized hydrate of, ix. 151 ; carbovinate of, xi. 320 ; bicarbonate of, its preparation, xii. 216; on the equivalent of, xii. 324 ; and oxalate of chromium, optical properties of, vii. 436. Potatoe starch, viii. 586. Potassium, experiments with, iv. 318; cyanuret of, v. 465 ; ferrocyanuret of, and dilute sul]»hurie acid, reaction of, vi. 97 ; chloride of, ix. 232 ; chloride of, detection of salt in, xii. 130 ; cya- nide of, as produced in hot-blast fur- naces, X. 329 ; ferrocyanide of, its action on sulphovinates and sulpho- methylates, xii. 102; and mercury, bromo-cyanide and chloro-cyanide of, xi. 340. Potter (R. jnn.) on giving conic sectional figures to lenses, &c., i. 55 ; on the reflexion at the second surface of flint glass at incidences of total reflexion, i. 57 ; on a new photometer by com- parison, i. 174; rejdy to Mr. Wheeler respecting, xii. 484 ; on a particular modification of the interference of ho- mogeneous light, ii. 83 ; Prof. Airy's remarks on, ii. 161 ; reply to Prof. Airy, ii. 276 ; Prof. Hamilton in reply to Mr. Potter, ii. 371 ; on a new he- liostat, ii. 6 ; on two arches of aurorae boreales, ii. 233 ; on a brilliant arch of an aurora borealis, iii. 422 ; on the ve- locity with which light traverses trans- parent media, iii. 333 ; on the reflexion of light by glass of antimony, iv. 6. Powell (Rev. B.) on experiments relative to the interference of light, i. 433 ; on the inflexion of light, ii. 424 ; on the undulatory theory of light, vi. 16, 107, 189, 262 ; on the repulsive power of heat, vi. 58 ; on the achromatism of the eye, vi. 247 ; on the dispersion of light, vi. 374; on M. Cauchy's theory of the dispersion of light, viii. 24, 204, 305 ; on the theory of dispersion, viii. 112, 413; X. 221; xi. 477 ; xii. 367; on prismatic dispersion, vii. 293 ; on recent discoveries relative to radiant heat, vii. 296 ; remarks on M.Melloni's paper on the transmission of calorific rays, viii. 23 ; note on the transmission of radiant heat, viii. 186; on the for- mula for the dispersion of light, ix. 116; X. 221 ; on repulsion by heat, &c.,xii. 317; on Von Wrede's explanation of the absorption of light by the undu- latory theory, xii. 114. Pratt (Rev. J. H.), demonstration of the parallelogram of forces, v. 39 ; im- provement in Henslow's clinometer, v. 159; on the proposition that a func- tion of 9 and -^ can be developed in ^ only one series of Laplace's coefficients, viii. 474 ; demonstration of a proposi- tion in the Mecanique Celeste, remaiks on, ix. 84 ; reply to, ix. 254 ; on the equilibrium of fluids, xii. 385. lOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 45 Pratt (S.) on the geological character of the coast of Normandy, xi. 210. Prawn, on the growth of the, viii. 421. Precipitate, white, viii. 498; on the pow- der formed by the action of water on, xi. 428 ; products of the action of al- kalies in excess on, xi. 433. Pressure, on the principle of the least, iv. 89, 194, 271, 420. Prestwich (J.) on the ichthyolites of Gamrie, vii. 325 ; on the geology of Coalbrooke Dale, ix. 382; on some elevations of the coast of Banffshire, xi. 209. Prevost (Dr.) on muscular fibre, xii. 293. Prideaux (J.) on the meteor seen June 29th, 1832, &c. i. 307 ; on voltaic ac- tion, ii. 210, 251; on the theory of thermo-electricity, iii. 205, 262, 398 ; on Mr. Phillips's remarks on chemical symbols, iv. 41, 464 ; on the deduction of the dew-point, xi. 54 ; on the Kauri or Cowdee resin from New Zealand, xu. 249. Priestley (Dr.), commemoration of the centenary of the birth-day of, ii. 158, 317; report of, ii. 383; Fuseli's por- trait of, ix. 398. Prism, on the passage of light through a, ii. 284. Pritchard (A.) on test-objects for micro- scopes, ii. 335 : apparatus for illustra- ting the polarization of light, viii. 70. Projectile weapon of the native Austra- lians, xii. 329. Protochloride of mercury, action of am- monia on the, xi. 504. Protoxide of tin, v. 79. Prout (Dr.), reply to Dr. W. C. Henry, v. 132. Prunus padus, volatile oil of, ix. 155. Prussic acid, test for, iv. 151. Psen atratum, xii. 17. Pseudammonites, fossil genus, ix. 32. Psychometer, or measurer of refrigera- tion, viii. 61. Pullen's (Prof.) Gresham lectures, xii. 454. Puma, notes on the, iv. 299. Pulo Pinang, on the geology of, i. 224. Pulse, on the differential, viii. 63. Pyramids of Gizeh, xii. 379. Pyrenees, on a freshwater formation in the, iv. 376. Pyroacetic spirit, on the compounds de- rived from, xii. 100, 107, 109. Pyrogenous acids, iv. 385. Pyrometer, on a new register, i. 197, '261. Pvromucic acid, manufacture of, vii. 395; "composition of, vii. 429. Pyrophori, easy preparation of, x. 319. Pyrosmalite, crystalline form of, xi. 261. Pyrosoma, some remarks on the, iii. 299. Pyrotartaric acid, distillation of, v. 397. Pyroxylic spirit, on, ix. 77; x. 45, 116; discovered by Mr. PhiUp Tavlor in 1812, vii. 395, 427 ; on a fluid obtain- ed in manufacturing it, vii. 395 ; action of oxacids on, viL 538 ; \'iii. 85. QUADRUMANOUS animal, fossil, xii. 34. Quails of India, vii. 229. Quartz, new crystal of, x. 369. Quassia, formation of nitre in extract of, xii. 140. Quassin, on, xii. 222 ; preparation of, in a pure state, xi. 336. Quekett (E. J.) on the genus Chara of Hooker, xii. 97. Quetelet (M.) on shooting stars, xi. 268 ; on the height, motion, and nature of shooting stars, xi. 270. Quevenne (M.) on polygalic acid, xi. 561 ; on modified polygalic acid, xi. 562, Quinia, hydriodate of, xi. 218; iodate of, xi. 218 ; elementary composition of, xi. 335. and iodine, xi. 218. Quinine, iodide of, viii. 191. RADIATA, fossil, vii. 517. Radiation of heat, on, vii. 296, 297. Railways, ix. 377, 380; theory of gra- dients in, viii. 51, 97, 243; on vibra- tion of, viii. 70 ; remarks on iron rails, viii. 291, 439; locomotive engines upon, ix. 135. Rainbow, explanation of, on the doctrine of interference, viii. 78. Rainey (G.) on the feeble attraction of the electro-magnet for small particles of iron, ix. 72, 220 ; reply to Dr. Rit- chie, ix. 469 ; on magnetic reaction, x. 193. Rain-gauge, self-registering, viii. 69; new, xi. 260, 476. Raphides, composition of, xi. 339. Rathlin, zoology of, vii. 492. Read (S.) on a decimal system of mone- tary calculation, vi. 441. Reade (Dr.) on a permanent soap-bubble, xi. 375. (Rev. J. B.) on producing achro- matic light in solar and oxy-hydrogen microscopes, x. 185 ; on the solar rays that occasion heat, and on the solar and oxy-hydrogen gas-microscope, x. 219; on structure in the ashes of plants, and their analogy to the esse- 46 GENERAL INDEX OF VOLS. 1 12 OF THE ous system in animals, xi. 13, 413; on the composition of vegetable mem- brane and fibre, xi. 421 ; reply to the objections of Professors Henslow and Lindley, xi. 424. Rectangnlar forces, on, x. 105. Rees (G. O.) on the existence of titanium in organic matter, v. 398 ; on the pre- sence of titanic acid in the blood, vi. 201 ; on hvdrate of magnesia, x. 454. Refraction of heat, vi. 134, 205, 284, 366; viii. 103, 479; ix. 166, 170; of the rays in crystals, on the, i. 1, 136 ; polarization by, xii. 549. double, xii. 47, 145 ; exhibited in the oxalate of chromium and potash, vi. 305; xii. 47, 145; on Fresnel's theoiy of, x. 24. conical, iii. 114, 197. Refrigeration, mode of measuring, viii. 59. Reflexion, viii. 103, 246; polarization by, xii. 553 ; crystaUine, laws of, x. 42 ; reflexion from metals, on the laws of, X. 382. Regnault (M.) on sulphonaphthalic acid, xi. 565. Reichenbach (M.) on kreosote, iv. 390. Reid (Mr.) anatomical description of the Patagonian Penguin, vii. 519; on a new species of Perameles, xi. 198. Reimsch (M.) on chlorosulphurets of lead, copper, bismuth, and zinc, xi. 560. Ren wick (Prof.) on the height of the Rocky mountains of North America, X. 73. Reptile, gigantic, new, vii. 327. Repulsion by heat, on, xii. 317. Resin, Kauri or Cowdee, from New Zea- land, xii. 249 ; its use in the arts, xii. 253. Resins, chemical examination of, xi, 158. Resistance, on the solid of least, viii. 66. Respiration, on, xii. 300 ; on the mecha- nism of, ii. 354 ; theory of, vii. 141; of di\ing animals, vii. 502; of insects, ix. 532; of plants, on, xi. 537 ; of insects, xi. 189. and irritability, mutual relation of, i. 73. Respiratory organs, influence of the, vii. 212. Retin Asphalt, composition of, xii. 560. Retina, on the effect of compression and dilatation on the, i. 89 ; on the undu- lations excited in the, by luminous points and lines, i. 169 ; experiments on the efl'ect of Hght on, i. 251 ; ii. 162 ; iv. 241; vision of the, iv. 43; visibility of, iv. 354 ; of the eye of the common calamary, viii. 1. Retinic acid, salts of, xii. 562. Retingle, new carburets of, xi. 404. Retinnapthe, new carburets of, xi. 404. Iletinole, new carburets of, xi. 404. Reviews of books : — Dr. Goring and Mr. Pritchard's Microscopic Cabinet,i. 163; Edmonds's Life-tables, i. 204; E.Hodg- kinson on Suspension Bridges and Iron Beams, i. 207 ; Mr. Babbage on the Economy of Machinery and Manufac- tures, i. 208 ; Comparative Account, — Population of Great Britain, i. 218, 361 ; Dr. Pearson's Introduction to Practical Astronomy, i. 370, 450 ;Todd on the Anatomy and Physiology of the Organ of Hearing, i. 375 ; Bevan's Guide to the Carpenter's Rule, i. 457 ; Journal of the Asiatic Society of Cal- cutta, ii. 371 ; Report of the British As- sociation, &c.ii. 455 ; iii.129; Prof. Ren- nie's Alphabet of Scientific Cliemistiy, iii. 35 ; Dr. Pearson's Practical Asti'o- nomy, iii. 133 ; Leyboum's Mathema- tical Repository, iii. 239 ; Young's Ele- ments of Plane and Spherical Trigono- metry, &c., iii. 363 ; Theory and Solu- tion of Algebraic Equations, viii. 402 ; Analytical Geometry, xii. 602 ; Analy- sis of Inorganic Bodies, by J. J. Ber- zelius, translated by G. O. Rees, iii. 463 ; Abstracts of Philosophical Trans- actions, from 1800 to 1830, iv. 47 ; Mr. Lubbock's Mathematical Tracts, iv. 218 ; Rev. W. D. Conybeare's Re- port on Geological Science, iv. 427 ; Dr. Daubeny's Inaugural Lecture on the study of Botany, v. 75 ; Transac- tions of the Entomological Society, v. 462 ; Allan's Manual of Mineralogy, vi. 53; Parkes's Chemical Catechism (13th edit.) by Brayley, vi. 214 ; the West of England Journal of Science and Literature, vi. 293 ; Royle's Illus- trations of the Botany, &c. of the Hi- malaya Mountains, vii. 132 ; Sturm on the Solution of Numerical Equa- tions, vii. 384 ; Whewell's Newton and Flamsteed, viii. 139 ; Wiegmann's Her- petologia Mexicana, viii. 410; Cooper's Flora Metropolitana, viii. 411; Samou- elle's Entomologist's Useful Compen- dium, viii. 412 ; Webster's Principles of Hydrostatics, and Theory of the Equihbrium and Motion of Fluids, viii. 544 ; Pambour's Treatise on Locomo- tive Engines upon Railways, ix. 135 ; The Botanist, ix. 371 ; Gaudichaud's Vegetable Physiology, ix. 372; Solly on the Human Brain, x. 286 ; Leit- head's Electricity, xii. 127; Macfad- yen's Flora of Jamaica, xii. 263 ; Hood's Treatise on Warming Buildings, xii. 202 ; Curtis's Guide to an Arrangement LOND. AND EDIN. PHILOSOI'IUCAL MAGAZINE, 1832 1838. 47 of British Insects, xii. 202 ; Agnew on the Pyramids of Gizeh, xii. 379 ; Levy's Description of Ileuland's Collection' of Minerals, xii. 536. llhea Darwinii, xii. 450 ; Americana, xii. 450. Rhinoceros, vi. 151. Rhodizite, a new mineral, vii. 431. Richardson (M.) on the products of the decomposition of cyanogen in water, xii. 339. (W.), notice of the coast from Whit- stable to the North Foreland, v. 219 ; on selenite in the sands of the plastic clay near Heme Hay, viii. 558. Riddle (Mr.) on the longitude of the Edinl)urgh observatory, xii. 525. Rigaud (Prof.) on a curious deposition of ice on a stone wall, ii. 190 ; life of Dr. Halley, vi. 30G; on a note in the Quarterly Review respecting Mr. Whe- well, viii. 218 ; on Newton, \\'histon, ■ Halley, and Flamsteed, viii. 220 ; on the aurora borealis of Nov. 18, 1835, viii. 350 ; inquiry rcLitive to Dr. Pem- berton's translation of Newton's Prin- cipia, viii. 441. Rigg (R.) experiments on the vinous, ace- tous, and putrefactive fermentation, ix. 535 ; on analysing organic compounds, xii. 31, 232. Riley (Dr.) on fossil remains of Saurian animals, viii. 577. Riolite, viii. 261. Ritchie (Prof.) on the magneto-electric phajnomena discovered by Dr. Faraday, iii. 37 ; iv. 11 ; on the power of an electro-magnet to retain its magnet- ism, iii. 122, 145 ; experimental r^j- seaiches in electro-magnetism, iii. 145 ; on the rotation of closed voltaic cir- cuits, iv. 13 ; on the detonation of oxy- gen and hydrogen by a magnetic spark, iv. 104; remarks on Mr. Christie's Bakerian lecture, iv. 208 ; on magnetic action, viii. 55, 242 ; researches in electricity and magnetism, viii. 455 ; on certain differences between the per- manent and the electro-magnet, ix. 81 ; on certain improvements in the mag- neto-electric machine, ix. 223 ; on Mr. Rainey's theory of magnetic re- action, ix. 287 ; replies to Mr. llainey, X. 57; to the Rev. J. W. MacGauley, x. 1, 462; to the Rev. N. J. Callan, X. 61 ; on Newton's rings and the fixed lines of the spectrum, x. 183; on the velocity of sound in air, and that re- sulting from theory, x. 220 ; on the electric spark and shock from a per- manent magnet, x. 280 ; on the con- ducting powers of wires for electricity, xi. 192 ; on the heat in metallic and liquid conductors, xi. 193; notice of the late, xii. 275. Rive (Prof. A. de la) notice of M. Nobili, ix. 234 ; researches into the cause of voltaic electricity, xi. 274. Roads, parallel, on the theory of, vii. 433. Roberts (Mr.) on a machine which ren- ders objects visible while revolving 200,000. times in a minute, viii. 71. Robinson (Dr.) on the aurora of Nov. 18, 1835, viii. 236 ; on the determination of the constant of lunar nutation, xii. 110. and Russell on the mechanism of waves, xii. 112. Robiquet (M.) on gallic acid, xi. 323. Robison (Mr.) on the improvement of light-houses, ii. 221. Rocks, unstratified, relative position of metallic deposits with regard to, i. 225 ; Sihu-ian system of, vii. 46 ; ix. 489 ; various kinds of, vii. 222 ; structure of, vii. 320, 376, 445; on the jointed structure of, ix. 6, 172; carboniferous, of North America, ix. 127. Rocky mountains of N. America, heights • of, X. 78. Rodent animals, notes on several, ix. 68 ; xii. 445. Rodgers (F. and E.) on certain metallic cyanurets, iv. 91. Rofe (J.) on the geology of the neigh- bourhood of Reading, v. 212. Rogers (H. D.) on the geology of North America, vi. 64. Roos's (Hon. Capt. de) account of re- covering the stores from the wreck of the Thetis, iv. 363. Rose (C. B.) on the geology of West Norfolk, vii. 171, 274, 370 ; viii. 28. — — (Gustav) on osmiridium from the Ural, V. 101 ; on the formation of calc spar and arragonite, xii. 465. (Heinric) on the evolution of light during crystallization, vii. 534 ; on the combinations of ammonia with anhy- drous salts, xi. 141 ; on a combination of the anhydrous sulphiu-ic and sul- phurous acids, xi. 321 ; on the detec- tion of metallic chlorides in bromides and iodides, xii. 136 ; on some new compounds of chlorine, xii. 220; on chloride of tungsten, xii. 461. Rosenberger's (Prof.) Ephemeris of Hal- ley's comet, vii. 423. Ross (Captain), short account of his ex> pedition to the North Pole, iii. 394; on the position of the north magnetic 48 GENERAL INDEX OP VOLS. 1 12 OF THE pole, iv. 222 ; on the aurora borealis, vii. 304. Rotary motion of camphor, v. 152. Rothman (R. W.) on a very ancient solar eclipse observed in China, xii. 282. Roy (T.) on the ancient state of the North American continent, xi. 201. Royal Medals awarded to Sir J. Herschel and George Newport, Esq., x. 213, 214. Royal Geological Society of Cornwall, iii. 305 ; anniversai-y meeting of, xi. 478. Institution, proceedings of, i. 72 ; ii. 309 ; iii. 71 ; iv. 29G ; v. 74 ; vi. 394 ; vii. 70 ; viii. 348 ; ix. 71 ; x. 317, 485 ; xii. 451, 533. Irish Academy, x. 382, 487 ; xi. 131; xii. 97, 368. Society, proceedings of,i. 60; ii. 131, 291, 373, 464 ; iii. 37, 141, 215 ; iv. 125, 220, 291, 360, 436 ; v. 451 ; vi. 55, 142, 297, 371 ; vii. 136, 207, 411 ; viii. 147, 412, 545; ix. 376, 522; x. 62, 141, 210, 376; xi. 89, 189; xii. 204, 269, 347, 426 ; anniversaries of, ii. 374 ; iv. 127. Society of Edinburgh, iv. 70 ; viii. 424. Royle (J. F.) review of his Illustrations of the Botany, &c. of the Himalayan Mountains, vii. 132. Rubies, artificial, xi. 563. Ruby glass, on the colouring matter of, xi. 137. Rudberg (Prof.) on refraction of the rays of crystals, i. 1, 136 ; on the variations produced by temperature in the double refraction of crystals, i. 410; on the magnetic intensity at Paris, &c. &c. ii. 4 ; undulatory theory of dispersion, viii. 28, 113, 210. Rudge (E.) on the position of the South Magnetic Pole, vi. 371 ; ix. 104. Ruminantia, aiTangements of the, xi. 469 ; Camelidae, xi. 471 ; Cervidae, xi. 471 ; Moschidae, xi. 472 ; Capridae, xi. 473; Bovidae, xi. 473. Rumker's (C.) new method of reducing lunar observations, vii. 251 ; viii. 373; on the solar ecUpse of May 15, 1836, X. 180. Riippell (Dr.) on the fossil genera Pseud- ammonites and Ichthyosiagonites of the Solenhofen limestone, ix. 32 ; on a new species of sword-fish, ix. 67 ; on the existence of canine teeth in an Abyssinian antelope, ix. 141. Russell (J. S.) on the motion of floating bodies, vii. 302 ; on the sohd of least resistance, viii. 66. Rust, effect of, in improving the quality of steel, ii. 75, 406. SABINE (J.), notice of, x. 468 ; xii. 276. Saccharates, baryta and strontia, xi. 156 ; potassa and soda, xi. 156. Safety-lamps, on the wire gauze of, vii. 411. tube for combustion of hydrogen and oxygen, i. 82. Salmonidae, on the aflSnity of fossil scales of fish with those of the recent, xi. 300. Salsaparin, analysis of, v. 464 ; composi- tion and properties of, xi. 337. Salt, its detection in chloride of potas- sium, xii. 130 ; process for the purifica- tion of, xii. 218. springs, on their strength at dif- ferent depths, iv. 31. Salts : — insoluble, employment of in ana- lysis, vi. 79 ; deliquescent, preservation of, vi. 319 ; water as a constituent of, vi. 327, 417 ; of sulpho-methylic acid, vii. 397 ; their solubility in muriate and nitrate of ammonia, x. 95, 178, 333; on the constitution of, x. 216; xi. 397 ; metallic, pecuhar action of iron upon solutions of, x. 267, 276; double, of mercury, analysis of, xii. 235 ; efflorescent, absorption of water by, xii. 130 ; on some remarkable, xii. 102; of retinic acid, xii. 562. San Fernando, mine of, xi. 22. Santaline, M. Pelletier on, iii. 312. Santini (Prof.), observations on Biela's comet, ii. 378. Sap, ascent of the, x. 494 ; circulation of, in Cissus hydrophora, xi. 525 ; distri- bution of, in plants, xi. 526 ; elabora- tion of, xi. 527. Sapyga 4-guttata, xii. 15. Sarcocoline, M. Pelletier on, iii. 313. Sarsaparilla, on the active principle of, v. 463. Saturn, occultation of, observed at Ge- neva, i. 327. Saunton Downend and Baggy Point, on the raised beaches of, xi. 117. Saurian bones in the magnesian conglo- merate, V. 463 ; reptile, description of a, ix, 514. Saxton (J.) on his magneto-electrical machine, ix. 360. Say's instrument for taking specific gra- vities, improvement in, v. 203. Scanlan (M.) on a fluid obtained in ma- nufacturing pyroxylic spirit, vii. 395. Scheele's artificial malic acid, iv. 74. Schiede (Dr.) on the Oxalis tuberosa, LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 49 Solanum tuberosum, Cevadilla, Aiuole, &c., vii. 500. Schleiden (Dr.) on the development of the organization in phaenogamous plants, xii. 172, 241, 292. Schoenbein (Prof.) on the action of nitric acid upon iron, ix. 53, 259 ; on a pe- culiar voltaic condition of iron, x. 133, 267, 425, 428 ; on Faraday's hypothe- sis on the causes of the neutrality of iron in nitric acid, x. 172 ; on the vol- taic relations of certain peroxides, pla- tina, and inactive iron, xii. 225 ; on the current electricity excited by che- mical tendencies, xii. 311 ; on the pe- culiar voltaic inactivity of bismuth and iron, xi. 544. Schomburgk (R.H.) on the tree from which the Indians prepare the poison called wooraly or ourary, x. 72; de- scription of the Pithecia leucocephala of Geoffroy St. Hilaire, x. 73. Schulke, on the composition of amylum, xi. 422. Schumacher (Prof.) on the imperial standard troy pound, x. 63. Schweitzer (G.) on the cause of the pre- sence of lead in English chemical pre- parations, viii. 267. Sciagraphicon, a new optical instrument, iii. 464. Scientific Memoirs, notice relative to, x. 81. Scolopacidae of Nepal, notice of, ix. 143. Scoresby (W.) improvements in magne- tical apparatus, xii. 380. Scott (D.), notice of, iv. 447. Scouler (Dr.) on hills of gravel in Ireland containing marine shells, x. 471. Scrope, (P.), voltaic theory, xii. 536. Scrymgeom* (James), experiments on the seconds pendulum, ii. 244, 344, 434. Sculpture, production of busts, &c. by machinery, viii. 70. Seals of Ireland, on the, x. 487. Sea-water, on the maximum density of, xii. 7. Sedgwick (Prof.) on the rocks of the Cumbrian mountains, i. 229 ; on the fossil shells of the Isle of Sheppey, ii. 149 ; on the geology of North Wales, ii. 381 ; on the geology of Cliamwood Forest, iv. 68 ; on the structure of mi- neral masses, and the aggregation of stratified rocks, vii. 320 ; on the Silu- rian and Cambrian systems, vii. 483 ; on the coal-fields on the N.W. coast of Cumberland, ix. 501 ; on a raised beach in Barnstaple bay, x. 477; on the physical structure of Devonshire, xi. 311. Seed-lac, production of, xi. 156 ; compo- sition of, xi. 157. Sells (W.) on the habits of the Vultur aura, xii. 447. Sementini (Sig.) on iodous acid, iv. 392. Sepia Loligo, on the eye of the, viii. 1 ; officinalis, on the ova of, iii. 301. Serum, composition of, iv. 156. Sevastopol, on the mean temperature of, i. 259. Sewalik hills, on a fossil monkey from the tertiary strata of the, xi. 393 ; on the remains of a quadrumanous animal found in the, xi. 208. Sewers, on the health of the workmen employed in cleansing, i. 354. Sharpe (D.) on the geology of Lisbon and Oporto, i. 227. Sheep, wild, description of, vi. 226. Shell, on a substance resembling, viii. 545 ; X. 201 ; new fossil shell, x. 239. Shells, on the structure of, iii. 452; new species of, iii. 61, 66, 69, 295, 301 ; v. 144, 148, 300, 312, 379, 382; vi. 68, 149, 387; vii. 153, 226, 318, 326; difficulty of distinguishing certain ge- nera of, vii. 210 ; on a bed of, at Eiie in Fifeshire, vii. 318. Shepherd (Dr.) on Edwardsite, xi. 402. Sherard (W.), the founder of the Profes- sorship of Botany at Oxford, viii. 424. Ship, on the brachystochronous course of a, iv. 33. Ship-sheathing, immersion of copper in mm-iatic acid for, vi. 444. Ships, new form for the construction of, viii. 66 ; on the dry-rot of, xi. 192. Shock-multiplier, correction in Heine- ken's paper on the, xi. 567. Shooting stars, on, xi. 268. Siebold (Dr. Von) on a double-bodied in- testinal worm, x. 253. Siliceous and calcareous products, xi. 403. Silk, analysis of, x. 323. Silurian system of rocks, on the, vii. 46, 483. Silver, desiccation of chloride of, iv. 397 ; on the assay of, vii. 425 ; action of chromic acid upon, xi. 489 ; iodide of, new property of, xii. 258 ; on the equi- valent of, xii. 324 ; oxide of, and oxide of lead, definite combination of, xii. 217 ; German, analysis of, viii. 80. Silvertop (C.) on the tertiary formation of Murcia, v. 220. Simia Morio, an orang of Borneo, x. 297. Simon (E.) on Jervine, xii. 29. Simpson and Dease's discovery of th^ North-west passage, xii. 542. G 50 GENERAL INDEX OF VOLS. 1 12 OF fHE Sines, table of, to centesimal parts of the versed sine, iii. 99. Siphuncle in the pearly Nautilus, on the action of the, xii. 503. Sitka, mean temperature of, i. 427. Sivatherium giganteum, ix. 193, 277; discovery of a head of the, xi. 208 ; notice of additional fragments of the, xii. 40. Skey (F.) on the muscular fibre of animal and organic life, x. 377 ; xi. 194. Skins, method of dressing in Morocco, iii. 297. Sleep, on the nature of, iii. 143. Sloth, on the structure of the, ii. 308. Smilacine, analysis of, v. 465. Smith (A.), method of finding the equa- tion to Fresnel's wave-surface, xii. 335. (J.) on some fossil trees, vii. 487 ; on changes in the relative level of sea and land in the West of Scotland, x, 136. (J. D.) on the composition of iodide of iron, vii. 156 ; analysis of German silver, and the separation of zinc from nickel, viii. 80 ; on the separation of barytes and strontia, viii. 259 ; on the composition of carbonate of zinc, viii. 261 ; on the hydrates of barytes and strontia, ix. 87 ; on the supposed new metal donium, ix. 255 ; on the solubi- lity of carbonate of hme in hydrochlo- rate of ammonia, ix. 540. • (Mr. T.) on certain phaenomena of vision traced to functional actions of the brain, i. 249 ; remarks on, ii. 168 ; on the muscularity of the crystalline lens, iii. 5. Smyrna, on the geology of, xi. 202. Snipes of Nepal, several kinds of, ix. 143. Snow, red, viii. 80. Soane (Sir J.), notice of the late, xii. 278. Soap-bubble, on a permanent, xi. 375. Societies : — Astronomical Society, grant of a royal charter to the, i. 234 ; proceedings of, ii. 222, 378, 475 ; iii. 231, 290 ; iv. 230, 295, 381 ; v. 300 ; vi. 221, 305, 449 ; vii. 69 ; ix. 291 ; x. 227 ; xii. 280, 521. British Association, i. 77 ; ii. 319, 455 ; iii. 151 ; iv. 319 ; v. 386 ; vii. 71, 118, 237, 289, 385, 480; viii. .W; ix. 228, 312 ; xi. 396, 474, 551. Cambridge Philosophical Society, i. 75, 400 ; ii. 314, 380 ; iii. 235, 461 ; iv. 66, 312, 463; vi. 73, 395; vii, 70 ; vui. 78, 429 ; ix. 71 ; x. 316, 485 ; xii. 452. Entomological Society, iv. 384 ; v. 236 ; vii. 420. Geological Society, i. 220; ii. 147, 300, 466; iii. 42, 219, 368; iv. 48, 147, 225, 370, 441 ; v. 53, 211, 292, 459; vi. 63, 146, 312, 376; vii. 52, 213, 316, 412, 513 ; viii. 71, 156, 310 ; ix. 382. 489 ; x. 68, 136, 306, 388, 471; xi. 98, 201, 307, 390; xii. 86, 284, 433, 508, 564. Roval Geological Society of Cornwall, iii. .305 ; vi. 153 ; xi. 478, Royal Institution, i. 72 ; ii. 309 ; iii. 71; iv. 296; v. 74; vi. 394; vii. 70 ; viii. 348 ; ix. 71 ; x. 317, 485 ; xii. 451, 533. Linnrean Society, i. 71 ; ii. 67, 222, 307, 377; iii. 69; iv. 52, 150, 309, 381, 454 ; V. 70, 298 ; vi. 72, 220, 379; vii. 519; viii. 75, 255, 345, 423, 580 ; x. 71, 223, 464 ; xfl. 92. 531. Meteorological Societv, xii. 291, 601. Roval Society, i. 60, 378 ; ii. 131, 291, 373, 464 ; iii. 37, 141, 215 ; iv. 125, 220, 291, 360, 436 ; v. 451 ; vi. 55, 142, 297, 371 ; vii. 136, 207, 411; viii. 147, 412, 545; ix. 376, 522; X. 62, 141, 210, 376; xi. 89, 189 ; xii. 204, 269, 347, 426. Royal Society of Edinburgh, iv. 70 ; viii. 424. Zoological Society, i. 392, 460 ; ii. 68, 230, 476 ; iii. 60, 148, 293, 372 ; iv. 54, 297, 377, 454 ; v. 72, 143, 230, 311, 379; vi. 68, 150, 223, 307, 380, 452; vii. 64, 152, 222, 328, 417, 519; viii. 161, 346; ix. 66, 136, 224, 298, 388, 503; x. 287, 479; xi. 118, 196, 394, 469; xii. 211, 441, 526, 592. Soda, carbonate of,its purification, v. 316; chloride of, its use in fever, viii. 64 ; on the equivalent of, xii. 324. Soda-alum, on the water of crystallization of, ix. 26. Sodium, experiments with, iv. 318 ; chlo- ride of, action of oxalic acid upon, v. 445. Solanaceae, property of the alkalies of the, xi. 334. Solania, iii. 464. Solar echpse, x. 180, 230; very ancient, xii. 282 ; solar eclipse of July 16, 1833, V. 305, 311; solar eclipse of May 15, 1836, viii. 293, 589, 590; ix. 73; me- teorological observations made during the, ix. 393. Solar rays that occasion heat, x. 219. spectrum, lines of the, viii. 384. Solid of least resistance, on the, viii. 66. Solids, linear expansion of, by heat, i. 266. Solly (E. jun.) on the conducting power of iodine, bromine, and chlorine for LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 51 electricity, viii. 130, 400 ; on the cow tree of South America, xi. 452. Solly (S.) on the connexion of the ante- rior columns of the spinal cord with the cerebellum, ix. 523. * Solutions, saline, maximum density of, xii. 7. Somerville's (Mrs.) mechanism of the heavens, i. 242. Soubeiran (M.) on sulphuret of azote, xii. 134. Sound, phaenomena of, iv. 1 7 ; on the pro- duction and propagation of, vi. 25 ; the- ory of, vii. 211; interference of, vii. 301 ; in air or vapour, velocity of,x. 220. Soundings in the ocean, new method of taking, ix. 185. South (Sir J.) on the atmosphere of Mars, iii. 37. Sowerby (J. De C.) on a phaenomenon resembling the mirage, seen in the Re- gent's Park, vii. 77 ; on the habits of the long-eared bat, viii. 265 ; on a new fossil sliell, X. 239 ; on his new genus, Tropaeum, of fossil shells, xi. 118. Spain, on the geology of, vii. 485. Spectra, prismatic, on, ix. 3 ; spectra of chemical flames, ix. 3 ; spectra of gal- vanic flames, ix. 4 ; on the supposed origin of the deficient rays in the solar spectrum, ix. 522. Spectrum, on the fixed lines of the, x. 183. Specific gravities, improvement in Say's instrument for measuring, v. 203. heats of dry gases, error in Dr. Ap- john's formula for inferring, viii. 21. Speech, by mechanical means, vii. 302. Spencer (E.) on the diluvium of Finchley, vii. 319. Spheroids, on a diflSculty in the theory of the attraction of, iii. 282. Sphinx Ligustri, on the nervous system of the, i. 382 ; vi. 55. Spider, account of an alleged bird-catch- ing, iv. 462. Spiders, their power to escape from an isolated situation, i. 424 ; entombed by the Trypoxylon, xii. 15. Spina bifida, on, x. 316, 486. Spinal cord, structure of the, vii. 138. marrow, on the reflex function of the, X. 51, 124, 187, 378. Spineto (Marquis di) on the Zimb of Bruce, and hieroglyphics of Egypt, iv. 170. Spirit-lamp furnace, new, vi. 292. Spring of Torre del Annunziata, vii. 317. Springs, variations in the quantity of water of, i. 287; iii. 417 ; analysis of two sulphureous springs near Wey- mouth, iii. 158. intermitting, on the phaenomena of, xii. 364. Squire (T.) on the solar eclipse of May 15, 1836, viii. 293. (P.) on the periodide of iron, ix. 79. St. Bernard, relative positions of the con- vent, and Chamouni, ii. 61. Starch, x. 235 ; action of iodine on, iv. 313; potatoe, viii. 586; experiments on, X. 247. Star-fish, on the, vii. 208. Stark (Dr.) on the influence of heat on colour and odours, iii. 458. Stars, Sir J. Herschel's observations of nebulae and clusters of, iv. 125 ; double, micrometrical measures of, v. 302; shooting, xi. 567. Statics, a new principle in, iii. 285 ; the- ory of resistances in, iii. 431. Steam, new facts on the production of, x. 378. Steam-engine, rotative, new, vii. 369. Steam-engines: — improvements in, viii. 71 ; of Cornwall, viii. 20, 136 ; rotatory, viii. 20, 136 ; work of the five best in Cornwall, ii. 318. Steam-vessel, iron, magnetic experiments on, viii. 547. Steam-vessels, on the motion of, v. 453. Stearate of methylene, on, xi. 487. Stearic aether, on, xi. 487. Stearon, v. 153. Steel, improvement of, from rust and being buried in the earth, i. 472 ; ii. 75, 406 ; action of sulphurous acid on, x. 235. Stephenson (J.), meteors observed in In- dia in 1832, ix. 74. Stevelly's (Prof.) mode of determining the dip of the magnetic needle, iv. 232 ; description of a self-registering baro- meter, viii. 67. Stevens (Dr.) on the theory of respu^tion, vu. 141. Stigmus troglodytes, xii. 16. Stokes (C.) on a piece of wood partly petrified by carbonate of Ume, with re- marks on fossU woods, ix. 499; on a petrified piece of wood from a Roman aqueduct, x. 476. Stotherd (Lt.) on a patch of granite in Cavan, vii. 482. Strickland (H, E.), account of land and freshwater shells found with bones of land quadrupeds, vi. 149 ; birds ob- served by him at Smyrna in the winter of 1835-36, X. 301; geology of the western part of Asia Minor, x. 68 ; geo- logy of the Thracian Bosphorus, x. 473 ; on the geology of Smyrna, xi.202 ; on the upper formations of the new red system, xi. 318 ; on the geology of the island of Zante, xii. 87 ; on some re- markable dikes of calcareous grit at Ethie, xii. 584. G2 52 GENERAL INDEX OF VOLS. 1 — 12 OF THE Strigisan, a variety of wavellite, viii. 173. Strix castanops, characterized, xi. 474. Stromever (Prof.) on the remarkable mass of iron discovered near Magdeburg, iii. 454, Stromite and thiilite, viii. 169. Strontia, carbonate of, discovered in the United States, vi. 234. and barytes, hydrates of, vi. 52 ; ix- 87 ; xi, 301 ; separation of, viii, 259. Structure in the ashes of plants, xi, 13. Struve (Prof.) on the measures of double stars, X, 229 ; on the siliceous contents of plants, xi, 339. Strychnos toxifera, the tree from which the Indians prepare the poison called wooraly, x, 72. Sturgeon, new species of, vi. 386, Sturgeon (W,) on the distribution of mag- netic polarity in metallic bodies, i. 31 ; on magnetic electricity, ii, 32 ; on the theory of magnetic electricity, ii. 201, 366 ; on the therrao-magnetism of sin- gle pieces of metal, and the electro- decomposition of metallic solutions, iii. 392; caution to experimenters with the electrical kite, v, 317 ; magneto-electri- cal experiments, v, 376 ; Mr, Watkins's observations on, vi, 239 ; reply to Mr. Watkins, vii. 231 ; description of a thunder-storm, v. 418; on an aurora borealis seen at Woolwich, vi. 230 ; description of the aurora borealis of Nov. 18, 1835, viii. 134 ; on electro- pulsations and electro-momentum, ix. 132 ; on the relative merits of magnetic electrical machines and voltaic batte- ries, X, 65, Stutchbury (S,) on various fossil remains of Saurian animals, viii. 577. Suberic acid, viii, 443. Submaiine forest in Cardigan Bay, ii. 148, 241. Suboxide of lead, v. 79. Subterranean sounds, on the cause of, i. 221. Succinic acid and its combinations, vii. 238. Suffolk, on the crag-formation and organic remains of, vii. 81, 353 ; on the geology of, xi. 106 ; physical features and geo- logical structure of, xi. Ill; geological survey of, xii. 512. Sugar, its conversion into formic acid and ulmin, vi. 399 ; crystallized, from the juice of the cocoa-nut palm, x. 77 ; of milk, on its fermentation, xii. 139. Sulphate of copper, action of hydrochloric acid on, viii. 353 ; voltaic battery charged with, x, 244 ; its use for ex- citing voltaic electricity, xi. 145. Sulphates, action of muriate of ammonia on, vi, 235 ; of iron and copper, action of oxalic acid on, ix, 155. Sulphindylic acid, x. 324. Sulpho-benzide and nitro-benzide, viii. '257. Snlphomesitylates, xii, 100. Sulpho-methylic acid, salts of, vii. 397. Sulphonaphthalic acid, xi. 565. Sulphovinates and sulphomethylates, ac- tion of ferrocyanide of potassium on, xii. 102, Sulphur, detection of minute portions of, vi. 399 ; vaporization of, viii, 189. Sulphureous springs (Nottington Spa and Radipole Spa), analysis of, iii, 158, Sulphur et of nickel, form of, vi, 104 ; of zinc and iron, vii. 79 ; of carbon, on the preparation of, xi. 221 ; of azote, xii, 134 ; of hme, on the, xi. 195. , metallic, on their employment in analysis, xii. 137. Sulphuric acid, manufacture of, iii. 115 ; apparatus for freezing water by the aid of, V, 377 ; its action on oils, ix. 153 ; anhydrous, its action on some metallic chlorides, x. 157 ; analogy of alcohol and indigo considered in their combi- nation with, X. 324 ; English, arsenic in, vii, 235. and sulphurous acids, anhydrous, on a combination of, xi. 321. Sulphurous acid, action of, on the persalts of iron, ii. 75 ; its action on steel, x. 235 ; its detection in hydrochloric acid, ix, 543. Sun, remarkable phaenomenon that occurs in eclipses of the, x, 230. Sun's rays, greater calorific effect of in high than in low latitudes, vii. 182. Suspension-bridges, Hodgkinson on, i. 207. Sussex (H. R, H, the Duke of) address of, at the anniversary meetings of the Royal Society, iv. 127, x, 141 ; xii, 269 ; ad- dress on the delivery of the Royal medal to Sir J, F, W. Herschel, x. 213. Swainson (W.) on the genus Mitra, ix. 136. Switzerland, on an optical phaenomenon seen in, ii, 452, Sykes (Col,), catalogue of birds from Dukhun, ii. 230 ; on the geographical distribution of birds, vii, 418; on the geographical range of birds, vii, 493 ; on the geology of Dukhun, ii, 304 ; on the atmospheric tides and meteorology of Dukhun, vi. 59 ; on the caves of Ballybunian, viii. 574 ; on the Quails and Ilemipodii of India, vii, 229 ; on the measurement of heights, vii, 311. Sylvester (J. J.) on the optical theory of crystals, xi. 461, 537; xii. 73, 341. LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 53 Sylvic acid, examination of, xi. 164. Symbolic notation, on, viii. 101. Symmetrizingpoweroftheeye,x.234,370. Syngamus trachealis, x. 253. Syngnathus Acus and Typhle, vi. 383. Syria, on the earthquake in, xi. 204. TW. W. on the visibiUty of the retina, • V. 354. Tabuloscriptive engine, x. 486. Tadpoles, mode of closure of the gill-aper- tures in, xii. 527. Talbot (H. F.) on chemical changes of colour, ii. 359 ; on an optical phaeno- menon seen in Switzerland, ii. 452 ; method of obtaining homogeneous light of great intensity, iii. 35 ; pro- posed philosophical experiments, iii. 81 ; remarks on, iii. 204, 352 ; on facts re- lating to optical science, iv. 112, 289 ; ix. 1, 401 ; on the arcs of the equilateral hyperbola, iv. 225 ; experiments on light, V. 321; vii. 113, 157; on the arcs of certain parabolic ciu"ves, v. 455 ; on the repulsive power of heat, viii. 189 ; on the integral calculus, viii. 549 ; X. 210; on the optical phaenomena of crystals, ix. 288 ; x. 218 ; experiment on the interference of light, x. 364 ; on a new property of nitre, xii. 145 ; on a new property of the iodide of silver, xii. 258. Tannin, its action on the roots of plants, V. 157. Tartaric acid, isomeric modification of, i. 83; distillation of, V. 397; constitution of, xii. 381. and paratartaric acid, xii. 605. Taylor (J.) on a new rotative steam- engine, vii. 369 ; on the duty of steam- engines in Cornwall, viii. 67 ; on rota- tory steam-engines, viii.*136; on man- ganese ore containing silver, x. 279. (PhiUp), discovery of pyroxylic spirit by, vu. 395, 427. (R.) on the doctrine of the eternity of the world, viii. 220, note ; on the frost of the 19th and 20th of January, 1838, xii. 303 ; on the destruction of an- cient painted glass, ix. 458, note ; on the history of glass-painting, ix. 456, 459, notes ; notice relative to the " Scientific Memoirs," x. 81. (R. C.) on the carboniferous series of the United States, ix. 407 ; on a vein of liituminous coal in the island of Cuba, X. 103; on the geology of Hol- guin in Cuba, and the mineral region on the N.E. coast, xi. 17. (T.) on two calculi composed of cystic oxide, xii. 337 ; on urinary cal- culi, xii. 412. Taylor (Mr.) on the solubility of arsenious acid, xi. 482. Taylor's theorem, on, vii. 188. Tea-plant, natural history of the country where found, xi. 390. ' Telegraphs, modern, on, v. 241, 365. Telescope, on the invention of, i. 9 ; the interior of the eye reflected on the eye- glass of the, i. 318; account of DoUond's fluid-refracting, ii. 373 ; zenith, twenty- five feet, vi. 373. Telescopes, application of the negative achromatic lens to, v. 452. Tellurium, on, iv. 75 ; preparation of pure, vii. 539 ; properties of, viii, 84 ; analysis of the sulphoplumbiferous, ii. 404. Temperature, mean, of Nicolaieff, i. 132 ; of Sevastopol, i. 259 ; of Sitka, i. 427 ; of Jloulouk, i. 429 ; its influence in pro- ducing vibration in metals, iv. 186 ; of vapours, vii. 159 ; thermometer for de- termining minute differences of, viii. 57 ; of insects, xi. 189 ; subterranean, v. 446. TenerifFe, meteorology of, xii. 291. Tennantite, analysis of, x. 236. Terebratula, on the anatomy of, iv. 302. Teredo navalis, vi. 55. Terrestrial magnetic intensity, experi- ments on, xi. 58, 254. Thames, difference of its level and the sea, i. 187. Thehaia, a new alkali in opium, viii. 444. Thebaine, composition of, x. 387. Thermal spring at Mallow, variations of temperature in, v. 216. Thermal springs, temperature of, viii. 551. Thermo-electric pha;nomena, on, xii. 295 ; spark, on the, xi. 398. Thermo-electricity, on, xi. 304 ; on the theory of, iii. 205, 262, 398; decom- position of water by, xii. 541. Thermo-magnetism of single pieces of metal, iii. 392. Thermo-multiplier, use of, xii. 545. Thermometer: — ^for determining minute differences of temperature, viii. 57 ; fallacy of determining climate by the, viii. 61 ; for measuring refrigeration, viii. 61 ; verification of, viii. 552. Thermometers, measurement of heights by, vii. 311. Thermometrical diary, specimen of a, xii. 489. Thetis, recovery of the stores from the wreck of the, iv. 363, 367. Thibaut (M.) on the giraffe, ix. 144. Thompson (J. V.) on the metamorphosis of the Cirripedes, vi. 373 ; on the me- tamorphoses in theMacroura, viii. 421. (L.), method of pieparing iodous acid, ix. 442 ; on the solubility of me- tallic oxides and salts in muriate of 54. GENERAL INDEX OF VOLS. 1 12 OF THE ammonia, x. 1 79 ; on antimoniuretted hydrogen, x. 353. Thompson ( W.) on some crystals of snow, V. 318 ; on the Teredo navalis and Lim- noria terebrans, vi. 55. Thomson (Dr. A. T. ) on the action of chlo- rine on metallic iodides, iv. 467. (Dr. J.) on the interpretation of formulae in spherical trigonometry, x. 18 ; formulae for the rectification of the circle, x. 210. (J.) on the mummy cloth of Egypt, V. 355 ; on the fibres of cotton, vi. 1 70. — — (Dr. R. D.) on the preparation of boron, x. 419. (Dr. T.) on sesquisulphate of man- ganese, viii. 173; on the right rhom- bic baryto-calcite, xi. 45. (T. S.) on the law of the diffusion of gases, iv. 321. Thrush, Himalayan^ vii. 227. ThuUte and stromite, viii. 169. Thunder-storm, description of a, v. 418. Thunder-storms,phaenomena accompany- ing, iv. 343. Tiarks (Dr.) notice of, xii. 274. Tide-gauge, new, xii. 430. Tides, on the, iii. 129, 143, 216 ; iv. 362 ; vii. 136, 208, 212, 293 ; viii. 430 ; x. 317, 380, 381 ; xi. 195 ; xii. 351 ; in the port of London, iv. 223 ; ix. 528 ; re- sults of extensive observations, ix. 528; in the Bay of Morecambe, v. 264 ; at Liverpool, viii. 147, 418, 547 ; on Ber- noulli's theory of, vii. 457 ; Prof. Pul- len's lectures on the, xii. 454 ; on the mechanism of waves, xii. 112; atmo- spheric, of Dukhun, vi. 59. Tiedemann (Dr.) on the brain of the ne- gro, ix. 527. Tiger, on the cranium of the, iv. 454. Tigris, on its union with the Euphrates, iv. 107. Tilgate Forest, on the fossil reptiles of, ii. 150. Tin, protoxide of, v. 79 ; preparation of protoxide of, xii. 216. plate, attempts to prevent the cor- rosion of, vii. 391. pyrites, analysis of, x. 236. Timber, on the strength of, i. 116. Titanic acid, its existence in Hessian cru- cibles, vi. 113 ; in the blood, vi. 201. Titanium in organic matter, v. 398. Toad, on a new species of, vii. 328. Tobacco, Irish and Virginia, comparative value of, vii. 393. Tobin (Sir J.) on the cast-iron ring money found on board the wreck of a vessel, xi. 131. Tod (D.) on the anatomy and physiology of the ear, i. 375. Tonna (L.) on some curious facts respect- ing vision, vi. 409. Torpedo, electricity of the, i. 67 ; obser- vations on the, vi. 57 ; chemical com- position of the electrical apparatus of, xii. 256 ; researches relative to the, xii. 196. Torsion balance, its application to inqui- ries in electricity, vii. 304 ; an improve- ment of the, vii. 303. Tortoise, vi. 152, 229, 380 ; vii. 65, 229 ; freshwater, type of a new genus of, v. 143. Tourmaline, on the electricity of, v. 133; polarization of heat by, vi. 205. Touraco, anatomy of the, iv. 456. Tovey (J.) on the relation between the velocity and length of a wave of light, viii. 7, 270, 500; on the undulatory theory of light, ix. 420 ; on an alleged demonstration of Fresnel relative to the wave-surface, xi. 524 ; on the cause of elliptical polarization, xii. 10; on the optical theory of crystals, xii. 259. Towers (G.) on the reception of coloured fluids in plants, xi. 533. Toxodon Platensis, xii. 516 ; on the cra- nium of the, xi. 205. Trail (Dr.) on the geology of Spain, vii. 485. Transition rocks of Wales, Shropshire, &c., on the, iv. 370. Tredgold (T.) notice of, iv. 394. Trevelyan (A.) on an unobserved property of chlorine, iii. 72 ; on the vibration of heated metals, iii. 321 ; vi. 85 ; de- scription of a new spirit-lamp furnace, vi. 292. (W. C.) on fragments of garnet in the mill- stone grit, vi. 76 ; on indica- tions of recent elevations in Guernsey and Jersey, xii. 284. Trigonometry, spherical, on the interpre- tation of formulae in, x. 18. Trigonometrical functions, v. 198. height of Ingleborough, vi. 248, 429. lines, the signs of, vi. 86. measurements, ix. 96. Trimmer (T.) on marine shells found near Shrewsbury, vii. 516. Tringa minuta, notice of, ii. 100. Tripoli, composed wholly of infusorial exuviae, ix. 158, 392. Trogon, on several species of, vii. 226. Trommsdorflf (M.) on gentianin, xii. 221. Tropaeum, a new genus of fossil shells, xi. 118. Trypoxylon figulus and T. clavicerum, habits of, xii. 15. Tubularia, on several specimens of, ix. 507. LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 55 Tungsten, on some compounds of, x. 322 ; chloride of, xii. 461. Turf, manufacture of paper from, vii. 401. Turner (Ur. E.) on some atomic weights, i. 109 ; iii. 488 ; on the chemistry of geology, iii. 20, 448 ; on the action of high pressure steam on glass, v. 297; on the colouring matter of the green- sand formation, xi. 36 ; notice of, xii. 275, 436. Turpentine, hydrate of oil of, vii. 537. Turpin on the occurrence of acicular cry- stals in the tissue of the Aroidese, xi. 444. Tyrrell (J.) on the blood in insects, vi. 300. ULMIN and formic acid, conversion of sugar into, vi. 399. Undulatory theory of light, vi. 16, 107, 189, 262; vii. 113, 293; viii. 7, 24, 113, 204, 247, 270, 305, 413, 429, 500; ix. 401,420; x. 24 ; xii. 10, 114; que- ries respecting, vi. 398 ; application of photometry to, v. 439. Unger (M.) on the occurrence of the car- bonate of lime on the leaves of Saxi- fragae, xi. 445 ; on the reception of coloured fluids in plants, xi. 535. United States, geological survey of, v. 466. University of London, evening meetings of the Professors, ii. 479. Uranus, on the satellites of, iv. 381 ; va- lue of the mass of, xii. 522. Ure (Dr.), analysis of the Moira brine spring, vi. 58 ; Dr. Daubeny on, vi. 321 ; on the modes of warming and ventilating apartments, x. 64. VALENTINE (W.), on the structure of vegetable membrane, xi. 437 ; on the dots of spiral tubes, xi. 441 ; on the ex- istence of stomata in mosses, xii. 533. Valerianic audits salts, v. 396. Valparaiso, effects produced by the earth- quake of Nov. 1822 at, vui. 159. Vapour, on certain properties of, iii. 38. Vapours from boiling solutions, tempera- ture of, vii. 159. Vegetable membrane and fibre, chemical composition of, xi. 421. physiology, progress of, xii. 53. Vegetables, classification of, vi. 379 ; x. 37, 108 ; system of circulation in, xi. 528 ; on secretory organs of, xi. 530 ; reception of sap, the secretion and nu- trition of, xi. 531. Vegetation, influence of the climate of Naples on, iv. 274 ; v. 46, 102 ; action of gases on, iv. 316; in a solution of arsenic, x. 324. Veins, mineral, x. 394; ix. 8, 387; me- thod of imitating, ix. 229. Velocity of sound in air or vapour, x. 220. Velocities, virtual, on the proof of the principle of, ii. 16. Ventilating and warming apartments, on the modes of, x. 64. Venus, on the rotation of, i. 391. Vertebrata, subdivided into five classes, xii. 92. Verschoyle (Archdeacon) on the geology of Mayo and Sligo, ii. 149. Vesuvius, its eruption in 1834, vi. 374 ; on the lava of, i. 228 ; vii. 316. Vibrating surfaces, figures of, iii. 144. Vibration, phoenomena of, iv. 15, 182 ; of heated metals, iii. 321 ; vi. 85 ; on heat and light resulting from, vii. 342. Vignoles (Archdeacon) on bog timber, vii. 499. Viper of the Somersetshire Downs, vi. 153. Viscin, production of, xi. 157. Vision, on, v. 192 ; experiment on, x. 234, 370 ; some curious facts respecting, V. 375 ; on certain phaenomena of, i. 249 ; some facts respecting, vi. 409 ; of the blood-vessels of the eye, iv. 115, 354. Voice, physiology of the, ix. 201, 269, 342 ; human, cause of the grave and acute tones of, vi. 372. Volatile oil, ix. 155; from caoutchouc, ix. 321. oils, analysis of some, ii. 153. Volcanic strata, discoveries in, vii. 316. phaenomena, theory of, xii. 576 ; on the connexion of, xii. 584. Volcano in the Mediterranean, notice of, i. 60 ; remains of the recent, iii. 148, 447. Volcanos of Asia Minor, x. 70 ; on the theory of, xii. 533 ; elastic fluids evol- ved from, iii. 159 ; on the chemical theory of, viii. 250 ; eruption of Cose- guina, viii. 414. Volta-electrometer, on the, iv. 293. Voltaic action, on the theory of, ii. 210, 251 ; artificial crystals by, x. 171. battery, on the, vii. 411 ; improved, viii. 114 ; x. 241 ; practical results of the, viii. 121 ; voltaic combinations, viii. 421 ; Hare's voltaic trough, viii. 116, 119 ; use of caoutchouc for insu- lation in, ix. 120 ; construction of, ix. 283 ; xi. 76 ; employed in producing artificial crystals and minerals, ix. 229 ; x. 63, 65; charged with solution of sulphate of copper, x. 244 ; on the em- ployment of iron in the construction 56 GENERAL INDEX OF VOLS. 1 12 OF THE of, xi. 150 ; circuit, on the rotation of, iv. 13. Voltaic combinations, observations on, ix. 376 ; xi. 89 ; xii. 364 ; peculiar vol- taic condition of iron, ix. 53, 122; X. 133, 172, 267, 276, 425, 428 ; action of electricity in, x. 281 ; conditions of iron and bismuth, xii. 48 ; relations of certain peroxides, platina, and in- active iron, xii. 225, electricity, ix. 484 ; due to chemical action, and not to contact, ix. 60 ; on the phaenomena and laws of action of, xi. 68 ; on the use of sulphate of cop- per for exciting, xi. 145 ; explanation of the principles upon which the che- mical theory of, is founded, xi. 274. pile, theorj' of the, xi. 285 ; tensile effects of, xi. 288 ; dynamic effects of the, xi. 290 ; circumstances which af- fect the power of the, xi. 291 ; results arrived at, xi. 293, 294 ; results ob- tained by Breguet's metalhc helix, xi. 298 ; summary of, xi. 299. Von Hoff (M.), notice of, xii. 439-. Vultur aura, habits of, xii. 447. Vulture, habits of the, x. 479. w ,- , H. M., improvement in Say's in- strument for taking specific gra- vities, V. 203. Wagner (R.), on the compound eyes of insects, viii. 202. Wales, on the old red sandstone of, iv. 228. Walford (E. B.), subsidiary hypothesis to the electro-chemical theory of Sir H. Davy, viii. 170. Walker (A.) on the cause of the direc. tion of continents, mountain chains, migrations, civilization, &c., iii. 426; on the mountain chains of Europe and Asia, reply to, iv. 1. Walter (M.) on the bichromate of per- chloride of chrome, xii. 83. Walton (Rev. W.) on the helm wind, x. 221. Ward (F. 0.), physiological remarks on the motion of the arm, ix. 411, 534. ■ (N. B.) on the reproduction of the fronds of Laminaria digitata, xii. 96. Wardrop (J.) on the influence of the re- spiratory organs, vii. 212. Warming and ventilating apartments, modes of, x. 64. Warrington (R.) on chemical symbols, i. 181. Wartmann (M.) on the periodical me- teors, xi. 261. Warwickshire, on the upper formations of the new red system in, xi. 318. Water, on the chemical agency of, ii. 237 ; its decomposition and reproduc- tion by electricity, iv. 291 ; its action on lead, v. 81 ; apparatus for freezing, V. 377 ; decomposition of, vi. 428; as a constituent of salts, vi. 327, 417 ; its absorption by efflorescent salts, xii. 130 ; its decomposition by thermo-elec- tricity, xii. 541; on the maximum den- sity of, xii. 1. Waterhouse (G. R.) on a new genus of mammiferous animals, ix. 520 ; on cer- tain differences existing between two specimens of Myrmecobius, xi. 200 ; on a new species of Mus, xii. 443 ; on new Rodentia, xii. 445 ; on several unde- scribed quadrupeds, xii. 596. Watkins (F.) on the sensation on the tongue from magneto-electricity, ii« 152 ; on Mr. Sturgeon's experiments in magneto-electricity, vi. 239 ; on mag- neto-electric induction, vii. 107 ; reply to Mr. Sturgeon, vii. 335 ; on thermo- electricity, xi. 304 ; on the thermo-elec- tric spark, xi.398 ; on electro-magnetic motive machines, xii. 190 ; on the low temperature of Jan. 1838, xii. 302 ; on the decomposition of water by thermo- electricity, xii. 541. Watson (H. H.), on the action of lime on solutions of carbonate of potash, iii. 314 ; on the absorption of water by efflorescent salts, xii. 130 ; detection of common salt in chloride of potas- sium, xii. 132. Watson (J.), an experiment in electricity, X. 326; mode of exhibiting the co- lours of thin plates, xii. 28. Wavellite, viii. 173. Wave-surface, on an alleged demonstra- tion of Fresnel relative to the, xi. 524 ; in the theory of double refraction, xi. 417; xii. 47. Waves, mechanism of, xii. 112, Wax, experiments on bees' and vegetable, i. 166 ; composition of various vegeta- ble, xi. 156; fossil, V. 316. Wazington (R.) on the action of chromic acid upon silver, xi. 489. Weaver (T.) on the gold-workings for- merly conducted in the county of Wicklow, vii. 1 ; on the carboniferous series of North America and Pennsyl- vania, ix. 124 ; X. 365 ; on the geological relations of North Devon, xii. 569. Webster's " Principles of Hydrostatics," and " Theory of the Equilibrium and Motion of Fluids," viii. 544. Welch (H.) on obHque bridges, x. 74. Well at Beaumont Green, on a, xi, 215. Wellsted (Lieut.) on the manna of Mount Sinai, and the dragon's blood tree and aloe plant of Socotra, x. 226. LOND. AND EDIN. PHILOSOPHICAL MAGAZINE, 1832 1838. 57 Werner's merits as a geologist, i. 274. West (Dr.) on the geographical ])osition of Cape Farewell, vii. 490 ; on the formation of wood, vii. 498. (W.) on a remarkable analogy be- tween ponderable bodies and caloric and electricity, v. 110. Westwood (J. d.) on several new British forms amongst the parasitic hymeno- pterous insects, i. 127 ; iii. 342 ; new Dipterous insects, vi. 280, 447 ; on the genus Nycteribia, vi. 392 ; on the sup- posed metamorphoses in the Crusta- cea, vii. 210; new hymenopterous in- sects, X. 440 ; on the family of Fulgo- ridae, xii. 93 ; on several new species of insects belonging to the family of sacred beetles, xii. 441. Wetherell (N. T.) on the fossils of the London clay, ix. 462 ; x. 239. Wharton (W. L.) on phagnomena of in- termitting springs, xii. 364. Wheatstone (Prof. C.) on the figures of vibrating surfaces, iii. 144 ; experi- ments to measure the velocity of elec- tricity and the duration of electric light, vi. 61 ; vii. 299 ; on the imita- tion of the human speech, vii. 302 ; on the thermo-electric spark, x. 414. Wheeler (J. II.) on the application of photometry to the undulatory theory of light, V. 439. Whewell (Prof.), paper on chemical sym- bols, remarks on, i. 181 ; on chemical formulae, iv. 9 ; on cotidal lines, iii. 216 ; on the tides in the port of Lon- don, iv. 223 ; on the results of tide observations, vii. 136 ; on a new ane- mometer, vii. 315 ; on the application of physical science to geology, vii. 489; notice of his pamphlet " Newton and Flamsteed," viii. 139; reply to the Quarterly Review, viii. 211 ; on the tides in the port of Liverpool, viii. 147 ; some observations on the tides, viii. 430 ; researches on the tides, viii. 547; ix. 528; x. 317, 380; xi. 195; on the artificial production of minerals, ix. 537 ; on the diurnal inequality wave on the coasts of Europe, xi. 195 ; on his instrument for registering aerial currents, xi. 474 ; lloyal medal ad- judged to, xii. 269, 351; address at anniversary of the Geological Society, xu. 434, 508. Whiston, remarks on, viu. 214, 220,225. White-lead manufactory, experiments on the atmosphere, of, vii. 77. Wiegmann, (M.) " Herpetologia Mexi- cana," viii. 410 ; notice of Ehrcnberg's discoveries respecting the Bacillariae, xi. 448. Wilkins (Sir C), notice of, x. 148. Williams (Rev. D.) on the ravines, passes, and fractures in the Mendip Ilills, v. 220 ; on some bones of animals disco- vered in the calcareo-magnesian con- glomerate, vi. 149 ; on some fossil plants, vii. 487 ; on the raised beaches of Saunton Downend and Baggy Point, xi. 117. (Dr. C. J. B.) on a new law of com- bustion, iv. 440; on the production and propagation of sound, vi. 25. Williamson (W. C.) on the organic re- mains in the lias and ooUtic of York- shire, V. 222 ; X. 137 ; on the lime- stones in vicinity of Manchester, ix. 24 1 , 348 ; on the affinity of fossil scales of fish with those of the recent Salmo- nidae, xi. 300 ; on fossil fishes in the Lancashire coal-field, xii. 86. Willis (Rev. Mr.) on the composition of the entablature of Grecian buildings, viii. 430 ; on the tabuloscriptive engine, x. 486. Wilton (Rev. C. P. N.) on the geology of the south-east line of coast of Newcastle in Australia, i. 92. Wind, on the velocity of, xi. 194 ; helm, on the, X. 221. Winds, outlines of a general theory of the, xi. 227, 353; notice relative to the theory of the, xi. 390 Wine, aethereal oil of, X. 417. Winch (N. J.) on the geology of North- umberland and Durham, iii.' 28, 92, 200, 273. Winckler (M.) on the products by distil- lation of bitter almonds and the leaves of the common laurel, xi, 160 ; on the preparation of pure quassin, xi. 336. Wires, electro-magnetic, conducting power of, xi. 1 ; on the conducting powers of, xi. 192. Wbhler, on borates of magnesia, v. 156; on crystallized oxide of chromium, viii. 175 ; on the preparation of bicarbonate of potash, xii. 216 ; on the definite com- bination of oxide of silver and oxide of lead, xii. 217. Wolfram, analysis of, vii. 335. WoUaston medals, awarded to Captain P. Cautley and Dr. II. Falconer, x. 306. WoUastonite and zurlite, vi. 76. Wombat, anatomy of the, ix. 504. Wood, on the formation of, vii. 498. Wood (A. T.) on the action of oxalic acid upon chloride of sodium, v. 445. Woodcocks, on the rearing of some, ii. 68. Woodward (S.) on the crag of Norfolk and Suffolk, vii. 353; on the crag formation, viii. 138. Woods (J.) on the species of f edia, vi. 380. 58 GENERAL INDEX OF VOLS. 1 — 12. Woolhouse (W. S. B.) on the enharmo- nic organ, vii. 366 ; on tlie theory of gradients on railways, viii. 243 ; on the theory of vanishing fractions, viii. 393 ; reply to Prof. Young, ix. 18, 209. Worcestershire, on the upper formations of the new red system in, xi. 318. Worm, vegetable mould produced by the digestive process of the, xii. 90 ; double-bodied intestinal, x. 253. Wrede's (M.von) theory of the absorption of light, on, xii. 114. Wright (T.) on Dr. Buckland's theory of the action of the siphuncle in the pearly nautilus, xii. 503. Wrottesley (Mr.), catalogue of the right ascensions of 1318 stars, x. 227. Wyatt (J.) on a trap-dyke in the Penrhyn slate quarries, xi. 103. Xon the undulatory theory, vi. • 398. X. Voluntary sounds of insects, x. 327. Xanthoniethilic acid, x. 488. Xanthophylle, the colouring matter of leaves in autumn, xii. 135. X. Y. Z., suggestions respecting the en- suing meeting of the British Associa- tion, vii. 118. YARRELL (W.) on the Apteryx Au- straUs, iii. 299 ; on a species of pipe- fish, viii. 347; on an insect destructive to turnips, viii. 347 ; on a mode of pre- serving fish peculiarly adapted for tra- vellers over land, Lx. 391. Yates (Rev. J.) on a submarine forest in Cardigan Bay, ii. 148, 241. York, city of, specification of trades in, i. 218. Yorke (Capt. P.), experiments on the ac- tion of water and air on lead, v. 81. Yorkshire, on the lower coal series of, i . 349 ; on the upper lias and marlstone of, ix. 497. Young (J.) on a new voltaic battery, x. 241. (J. R.) on certain trigonometrical functions, v. 198 ; on the summation of slowly converging and diverging infi- nite series, vi. 348 ; vii. 25 ; formula; for the summation of infinite series, x. 121 ; xi. 41 ; on the function Xo, vii. 454 ; on Mr. Woolhousc's theory of vanishing fractions, viii. 295, 515; ix. 92; theory and solution of algebraic equations, viii. 402 ; simple method of proving the law of gravitation, ix. 333, 370 ; on Prof. Wallace's property of the parabola, xi. 302; " Analytical Ge- ometry," xii. 602. ZACH (Baron de) notice of, ii. 144 ; portrait of, ix. Zante, geology of, xii. 87. Zimb of Bruce, on the, iv. 170. Zinc, its protection of other metals from corrosion, vii. 391 ; its separation from nickel, viii. 80 ; composition of carbonate of, viii. 259 ; plates, amalgamation of, viii. 585; chloro-sulphuret of, xi. 560. and iron, sulphuret of, vii. 79. Zinken (Von), on a new locality of arse- nical copper in Chili, xii. 217. Zoological Society, proceedings of, i. 392, 460 ; ii. 68, 230, 476 ; iii. 60, 148, 293, 372 ; iv. 54, 297, 377, 454 ; v. 72, 143, 230, 311, 379; vi. 68, 150, 223, 307, 380, 452 ; vii. 64, 152, 222, 328, 417, 519; viii. 161, 346;ix. 66, 136, 224, 298, 388, 503; x. 287, 479; xi. 118, 196, 394,469; xii. 211, 441, 526, 592. Zoology, fossil, on, ii. 473. Zurlite and Wollastonite, vi. 76. Printed by Richard and John E. Taylor, Red Lion.court, Flcct-street, '\^\ >*>: '0t xX iS^^ -^J ^r^