I PROCEEDINGS ROYAL SOCIETY OF LONDON. From January 12, 1865, to December 21, 1865, inclusive. VOL. XIV. LONDON: PRINTED BY TAYLOR AND FRANCIS, HEI) I.ION COTJBT, FLEET STREET. MDCCCLXV. Q • *«*£ '^r CONTENTS. VOL. XIV. Page On a Colloid Acid, a Normal Constituent of Human Urine. By William Marcet, M.D., F.R.S 1 Account of Observations of Atmospheric Electricity at King's College, Windsor, Nova Scotia.— No. II. By Joseph D. Everett, M.A., F.R.S.E., Professor of Mathematics in King's College, N.S 10 Notes of Researches on the Acids of the Lactic Series. — No. II. Action of Zinc upon a Mixture of Iodide of Ethyl and Oxalate of Methyl. By Edward Frankland, F.R.S., and B. F. Duppa, Esq 17 Preliminary Note on some Aluminium Compounds. By George Bowdler Buckton, F.R.S., and William Odling, M.B., F.R.S 19 On Bubbles. By Frederick Guthrie, Esq., Professor of Chemistry and Physics at the Royal College, Mauritius 22 Note on the Invisible Radiation of the Electric Light. By John Tyndall, F.R.S 33 Note on a New Object-glass for the Microscope, of higher magnifying power than any one hitherto made. By Lionel S. Beale, M.B., F.R.S., F.R.C.P., Professor of Physiology and of General and Morbid Anatomy in King's College, and Physician to King's College Hospital 35 Researches on Solar Physics. — Series I. On the Nature of Solar Spots. By Warren De la Rue, £h.D., F.-R.S., Balfour Stewart, A.M., F.R.S., Su- perintendent of the Kew Observatory, and Benjamin Loewy, Esq 37 On the Spectrum of the Great Nebula in the Sword-handle of Orion. By William Huggins, F.R.A.S 39 Further Observations on the Planet Mars. By John Phillips, M.A., LL.D., F.R.S., F.G.S., Professor of Geology in the University of Oxford 42 Notices of the Physical Aspect of the Sun. By John Phillips, M. A., LL.D., F.R.S., F.G.S., Professor of Geology in the University of Oxford 46 On a New Geometry of Space. By Julius Pliicker, For. Memb. R.S 53 Researches on Solar Phvsics. — Second Series. On the Behaviour of Sun- spots with regard to Increase and Diminution. By Warren De la Rue, Ph.D., F.R.S., President of the Royal Astronomical Society, Balfour Stewart, A.M., F.R.S., Superintendent of the Kew Observatory, and Benjamin Loewy, Esq 59 Page On the Rapidity of the Passage of Crystalloid Substances into the Vascular and Non-vascular Textures of the Body. By Henry Bence Jones, F.R.S. 63 Monthly Magnetical Observations taken at the College Observatory, Stony- hurst, in 1864. By the Rev. Walter Sidgreaves 65 Chemical Examination of the Fluid from the Peritoneal Cavity of the Ne- matode Entozoa. By Dr. W. Marcet, F.R.S 69 On the Commissures of the Cerebral Hemispheres of the Marsupialia and Mouotremata. as compared with those of the Placenta! Mammals. By W. H. Flower, F.R.S 71 Note on the Atomicity of Aluminium. By Professor A. W. Williamson, F.R.S., President of the Chemical Society 74 On the Synthesis of Tribasic Acids. By Maxwell Simpson, M.D., F.R.S. . 77 Notes of Researches on the Acids of the Lactic Series. — No. III. Action of Zincethyl upon Ethylic Leucate. By E. Frankland, F.R.S., and B. F. Duppa, Esq 79 Notes of Researches on the Acids of the Lactic Series. — No. IV. Action of Zinc upon Oxalic Ether and the Iodides of Methyl and Ethyl mixed in atomic proportions. By E. Frankland, F.R.S., and B. F. Duppa, Esq. . . 83 On New Cornish Minerals of the Brochantite Group. By Professor N. Story Maskelyne, M.A., Keeper of the Mineral Department, British Museum 86 Preliminary Notice on the Products of the Destructive Distillation of the Sulphobenzolates. By John Stenhouse, LL.D., F.R.S., &c 89 Preliminary Note on the Radiation from a Revolving Disk. By Balfour Stewart, M.A., F.R.S., and P. G. Tait, M.A 90 On the Quadric Inversion of Plane Curves. By T. A. HIRST, F.R.S 91 On the Marsupial Pouches, Mammary Glands, and Mammary Foetus of the Echidna Hystrix. By Professor Owen, F.R.S 106 Numerical Elements of Indian Meteorology. — Series II. Insolation, and its Connexion with Atmospheric Moisture. By Hermann von Sclilagint- weit HI On the Structure and Development of the Skull of the Ostrich Tribe. By WiUiam Kitchen Parker, Esq 112 On the Magnetic Character of the Armour-Plated Ships of the Royal Navy, and on the effect on the Compass of particular arrangements of Iron in a Ship. By Frederick John Evans, Staff- Commander R.N., F.R.S., Super- intendent of the Compass Department H.M. Navy, and Archibald Smith, M.A., F.R.S., Corresponding Member of the Scientific Committee of the Imperial Russian Navy 114 Inferences and Suggestions in Cosmical and Geological Philosophy. By E. W. Brayley, F.R.S ".120 On Zoological Names of Characteristic Parts and Homological Interpreta- tions of their Modifications and Beginnings, especially in reference to Connecting Fibres of the Brain. By Professor Owen, F.R.S 129 Reply to Professor Owen's Paper " On Zoological Names of Characteristic- Parts and Homulogical Interpretations of their Modifications and Be- Page ginnings, especially in reference to Connecting Fibres of the Brain." read before the Royal Society March 23, 1865. By W. H. Flower, F.R.S ..... 184 On the Size of Pins for Connecting Flat Links in the Chains of Suspension Bridges. By Sir Charles Fox .................................. 139 On the Influence of Quantity of Matter over Chemical Affinity, as shown in the formation of certain Double Chlorides and Oxalates. By George Rainey, M.R.C.S., Lecturer on Microscopical Anatomy, and Demon- strator of Surgical Anatomy at St. Thomas s Hospital .............. 144 Report on the New Unit of Electrical Resistance proposed and issued by the Committee on Electrical Standards appointed in 1861 by the British Association. By Fleeming Jenkin, Esq ........................... 154 Researches on the Hydrocarbons of the Series Cn H2?t+2. By C. Schor- lemmer, Esq., Assistant in the Laboratory of Owens College, Manchester . 164 Introductory Memoir on Plane Stigmatics. By Alexander J. Ellis, F.R.S. 176 Further Experiments on the Production of Organisms in Closed Vessels. By George Child, M.D ............................................... 178 On the Magnetic Character of the Iron-built Armour-plated Battery ' Per- venetz' of the Imperial Russian Navy. By Capt. J. Belavenetz, R.I.N., Superintendent of the Compass Observatory at St. Petersburg .......... 186 Notes of Researches on the Acids of the Lactic Series.— No. V. Action of Zinc upon a mixture of Ethyl Oxalate and Amyl Iodide. By Edward Frankland, F.R.S., and B. F. Duppa, Esq ........................... 191 Notes of Synthetical Researches on Ethers. — No. I. Synthesis of Butyric and Caproic Ethers from Acetic Ether. By Edward Frankland, F.R.S., and B. F. Duppa, Esq ........................................... 198 On the Properties of Liquefied Hydrochloric Acid Gas. By George Gore, On the Production of the so-called " Acute Cestode Tuberculosis " by the administration of the Proglottides of T&nia mediocctnellata. By James Beart Simonds, Esq., Professor of Cattle-Pathology in the Royal Veteri- nary College, and T. Spencer Cobbold, M.D., F.R.S., F.L.S ........... 214 On the Rate of Passage of Crystalloids into and out of the Vascular and Non-Vascular Textures of the Body. By Henry Bence Jones, A.M., M.D., F.R.S ......................................................... 220 Lunar Influence on Temperature. By J. Park Harrison, Esq., M.A ....... 223 On the ultimate Nerve-fibres distributed to Muscle and some other Tissues, with observations upon the Structure and probable Mode of Action of a Nervous Mechanism. Being the Croonian Lecture for 1865, delivered by Lionel S. Beale, M.B., F.R.S., Fellow of the Royal College of Physi- cians, Professor of Physiology and of General and Morbid Anatomy in King's College, London ; Physician to King's College Hospital ........ 229 On Newton's Rule for the Discovery of Imaginary Roots of Equations. By J. J. Sylvester, F.R.S ........................................... 268 On the Application of Physiological Tests for certain Organic Poisons, and especia the Application of Physiological Tests for certain Organic Poisons, and specially Digitalinc. By C. Hilton Faggc, M.])., and Thomas Steven- .D... .......... .......... , ......... .................... -'70 Page On the Corrections for Latitude and Temperature in Barometric Hvpso- metry, with an improved form of Laplace's formula. By Alexander J. Ellis, F.R.S 274 On the Elasticity and Viscosity of Metals. By Prof. W. Thomson. LL.D., F.R.S., F.R.S.E ; .289 On Two New Forms of Heliotrope. By W. H. Miller, M.A., For. Sec. R.S., and Professor of Mineralogy in the "University of Cambridge 297 Annual Meeting for the Election of Fellows 299 Communication from the President and Council of the Royal Society to the Board of Trade on the subject of the Magnetism of Ships 300 Correspondence between the Board of Trade and the Royal Society in reference to the Meteorological Department '. 306 Letter of Professor Dove on Meteorological communications, &c 317 Description of a Rigid Spectroscope, constructed to ascertain whether the Position of the known and well-defined Lines of a Spectrum is constant while the Coefficient of Terrestrial Gravity under which the Observations are taken is made to vary. By J. P. Gassiot, V.P.R.S 320 A Description of some Fossil Plants, showing structure, found in the Lower Coal-seams of Lancashire and Yorkshire. By E. W. Binney, F.R.S 327 On Symbolical Expansions. By W. H. L. Russell, Esq., A.B 329 On the Summation of Series. By W. H. L. RusseU, Esq., A.B 332 On a Theorem concerning Discriminants. By J. J. Sylvester, F.R.S 836 Some Observations on Birds, chiefly in relation to their Temperature, with Supplementary Additions. By John. Davy, M.D., F.R.S., &c 337 On the Heating of a Disk by rapid Rotation in vacua. By Balfour Stewart, M.A., F.R.S., and P. G. Tait, M.A 339 On the Fossil Mammals of Australia. — Part II. Description of an almost entire Skull of Thylacoleo carnifex, Ow. By Professor Owen, F.R.S., &c. 343 On the Normal Circulation and Weight of the Atmosphere in the North and South Atlantic Oceans, so far as it can be proved by a steady Meteorolo- gical Registration during five Voyages to India. By Captain Henry Toynbee 345 On the Sextactic Points of a Plane Curve. By William Spottiswoode, M.A., F.R S., «&c 349 Products of the Destructive Distillation of the Sulphobenzolates. — No. I. By John Stenhouse, LL.D., F.R.S., &c 351 An Account of the Base-observations made at Kew Observatory with the Pendulums to be used in the Indian Trigonometrical Survey. By Balfour Stewart, F.R.S., and B. Loewy, Esq 357 An Inquiry into the possibility of restoring the life of Warm-blooded Animals in certain cases where the Respiration, the Circulation, and the ordinary manifestations of Organic Motion are exhausted or have ceased. By Benjamin Ward Richardson, M.A., M.D 358 Vll Page On the Anatomy and Physiology of the Nematoids, parasitic and free; with observations on their Zoological Position and affinities to the Echinoderms. By Henry Charlton Bastian, M.A., M.B. (Lond.), F.L.S. 371 On the Development of Striated Muscular Fibre. By Wilson Fox, M.D., Professor of Pathological Anatomy in University College, London .... 374 Researches on the Structure, Physiology, and Development of Antedmi (Comatula, Lamk.) rosaceus. By Dr. W. B. Carpenter, F.R.S 376 On the Chameleon's Retina ; a further contribution to the Minute Anatomy of the Retina of Amphibia and Reptiles. By J. W. Hulke, Esq 378 Additional Varieties in Human Myology. By John Wood, F.R.C.S., De- monstrator of Anatomy in King's College, London 379 On New Cornish Minerals of the Brochantite Group. By Professor N. Story Maskelyne, M.A., Keeper of the Mineral Department, British Museum '. 392 On the Rate of Passage of Crystalloids into and out of the Vascular and Non-vascular Textures of the Body. By Henry Bence Jones, A.M., M.D., F.R.S ." 400 An Account of the Base-observations made at the Kew Observatory with the Pendulums to be used in the Indian Trigonometrical Survey. By Balfour Stewart, M.A., LL.D., F.R.S., Superintendent of the Kew Ob- servatory, and Benjamin Loewy, Esq 425 Some Observations on Birds, chiefly relating to their Temperature, with Supplementary additions on their 'Bones. By John Davy, M.D., F.R.S., &c 440 Synthetical Researches upon Ethers. — Synthesis of Ethers from Acetic Ethers. By E. Frankland, F.R.S., Professor of Chemistry in the Royal Institution of Great Britain, and in the Royal School of Mines, and B. F. Duppa, Esq ! 458 Researches on the Hydrocarbons of the Series Cn Han +2- — No. II. By C. Schorlemmer, Esq., Assistant in the Laboratory of Owens College, Man- chester 464 On the Laws of Connexion between the Conditions of a chemical Change and its Amount. By A. Vernon Harcourt, Esq., and W. Esson, Esq. . . 470 Supplementary Note to Dr. Davy's Paper on Birds , 475 On Calorescence. By John Tyndall, F.R.S 476 Notice of the Surface of the Sun. By John Phillips, M.A., LLD., F.R.S., &c., Professor of Geology in the University of Oxford ib, Notice of a Spot on the Sun, observed at intervals during one Rotation. By John Phillips, M.A., LL.D., F.R.S., Professor of Geology in the Uni- versity of Oxford 479 Anniversary Meeting : Report of Auditors 481 List of Fellows deceased, &c ib. elected si Address of the President vm Page Anniversary Meeting (continued) : Presentation of the Medals 493 Election of Council and Officers 513 Financial Statement 514 & 515 Changes and present state of the number of Fellows 516 Further Correspondence between the Board of Trade and the Royal So- ciety, in reference to the magnetism of Ships, and the Meteorological Department tb. Addition to the Memoir on Tschirnhausen's Transformation. By Arthur . Cayley, F.R.S 541 A Supplementary Memoir on the Theory of Matrices. By Arthur Cayley, F.R.S 543 On the Existence of Glvcogen in the Tissues of certain Entozoa. By Michael Foster, M.B ib. On the Development of certain Infusoria. By J. Samuelson, Esq 546 Numerical Elements of Indian Meteorology. — Series III. Temperatures of the Atmosphere, and Isothermal Profiles of High Asia. By Hermann de Schlagintweit, Sakiinlunski, Ph.D., L.L.D., Corr. Memb. Acad. Leop.- Carol., &c 547 On testing^ Chronometers for the Mercantile Marine. By John Hartnup, F.R. A.S., Director of the Liverpool Observatory 548 On the Expansion of Water and Mercury. By A. Matthiessen, F.R.S 551 On the forms of some Compounds of Thallium. By W. H. Miller, M.A., For. Sec. R.S., Professor of Mineralogy in the University of Cambridge. . 555 Obituary Notices of Deceased Fellows : Captain William Allen i Rev. Dr. William Cureton i Joseph Henry Green i Hudson Gurney v Leonard Homer v Luke Howard x William Chadwell Mylne xii Major-General Joseph Ellison Portlpck xiii Dr. Archibald Robinson xvii Giovanni Antonio Amedeo Plana xvii Heinrich Rose xix Friedrich Georg Wilhelm Struve xx PROCEEDINGS THE ROYAL SOCIETY. " On a Colloid Acid, a Normal Constituent of Human Urine." By WILLIAM MAUCET, M.D., F.R.S. Received May 28, 1864*. IN the autumn of 1862, feeling assured that, besides the known normal crystalloid compounds found in urine, this secretion contained colloid substances, I submitted samples of the healthy secretion, after concen- tration, first, to the process of dialysis, and then to the action of reagents, and finally succeeded in precipitating with alcohol a colloid substance ex- hibiting a faintly acid or neutral reaction, and containing a small proportion of ash. For a while my endeavours to obtain a definite compound from this amorphous mass were fruitless, until, on observing that basic acetate of lead produced a precipitate in its aqueous solution, I thought of examin- ing this precipitate, and, by decomposing it with sulphuretted hydrogen, found it to consist of an organic acid combined with lead. This new acid is possessed of the properties of a colloid substance ; it may be considered as having a definite combining proportion or equivalent weight, and is undoubtedly destined to become of great importance in physiological che- mistry. After having satisfied myself of the presence of a colloid acid in urine, I tried every means to obtain as much of it as possible from a given volume of the secretion, and prepare it in the pure condition ; and after having experienced many difficulties, I adopted the following method as the simplest and that yielding the most satisfactory results. Mode of Preparation of the Colloid Acid. Urine is mixed with animal charcoal and concentrated until reduced to about one-fourth of its original bulk. It is filtered, and a solution of caustic baryta is added until complete precipitation by this agent be effected. The fluid filtered from the baryta precipitate is dialyzed without further evapo- * Read June 16, 1864 : see Abstract, vol. xui. p. 314, VOL. XIV. B 2 Dr. Marcet on a Colloid Acid of Urine. [1864. ration, for a period of about forty hours ; after which it is again concentrated, filtered, and then a solution of basic acetate of lead is added to it, which produces a precipitate : care should be taken not to use more of this so- lution than is necessary to obtain a complete precipitation in the fluid. The precipitate appears white, although containing a little colouring-mat- ter ; it is to be collected on a filter and washed with distilled water until the washings contain but a trace of lead. The insoluble substance on the filter is a lead-compound of the organic colloid acid ; it still contains a small quantity of colouring-matter, some hydrated oxide of lead, more or less chloride of lead, and perhaps traces of sulphate of lead. In order to effect the removal of these impurities, the insoluble compound is first de- composed with sulphuretted hydrogen or sulphuric acid ; if sulphuretted hydrogen is employed, the excess of this gas is afterwards expelled by boil- ing, or better by blowing it out with a current of air. The acid fluid being now heated with animal charcoal and filtered, loses the whole, or nearly the whole of its colouring-matter, and apparently much of its urinous smell. Any hydrochloric acid present can be easily separated from the free organic acid by treating the colourless fluid with carbonate of silver and filtering ; the dissolved silver is afterwards eliminated by means of sulphuretted hydrogen, and the excess of sulphuretted hydrogen again re- moved by boiling the fluid, or passing through it a current of air. The careful addition of baryta- water will precipitate any sulphuric acid present. Finally the acid is precipitated afresh with basic acetate of lead, from which it is separated by decomposing the thoroughly washed precipitate with sulphuretted hydrogen. The object of the various operations thus described will be readily under- stood. By evaporating urine with animal charcoal, it is first partly dis- coloured ; the precipitation with baryta-water throws down the phosphoric and sulphuric acids and the lime of the secretion, which would interfere with further operations, and imparts to the fluid a strongly alkaline reac- tion, this last condition being apparently necessary to avoid a loss of the colloid acid during the dialysis. In order to prevent decomposition, which would occur by concentrating with heat a strongly alkaline urine, the fluid is dialyzed at once for about thirty-six hours, which operation removes from it a considerable proportion of its crystalloid constituents ; among these are chlorides, which it is advisable to get rid of, as much as possible, before concentration and precipitation with basic acetate of lead, because by so doing a great saving in the carbonate of silver, necessary to precipi- tate the remaining hydrochloric acid, will be effected. If basic acetate of lead is used in excess, the precipitate begins to redis- solve ; the precipitant should therefore be added very gradually, testing the fluid now and then to ascertain whether the precipitation be complete. I have also observed the precipitate to be soluble in a solution of caustic potash. The lead-compound collected on a filter is to be thoroughly washed, to remove any excess of basic acetate of lead, and a solution of the lead-compound of the colloid acid, to which I shall refer hereafter. 1864.] Dr. Marcet on a Colloid Acid of Urine. 3 As the lead precipitate appears to be slightly soluble in water, it is diffi- cult to ascertain precisely the period at which the washing may be con- sidered sufficient. I usually continued pouring distilled Water into the filter until sulphuretted hydrogen gave but a faint dark colour in the filtrate. The decomposition of the insoluble compound by means of sul- phuretted hydrogen is a slow process, and takes some hours before it is complete ; and it will be advisable to leave the precipitate in contact with sulphuretted hydrogen overnight : the excess of sulphuretted hydrogen may be expelled by boiling, or by a stream of air, by which latter method the coloration caused by heat is avoided. The Acid. — The fluid prepared as stated above has a strong acid reaction; exposed to the air for a fortnight, and even for a longer period, it is not altered. When concentrated even by very brisk boiling, it may be con- sidered as undergoing no loss and no decomposition, as shown by the fol- lowing experiments : — 75 cub. centims. of the acid, 5 cub. centims. of which were neutralized by 24'3 cub. centims. of a normal potash solution, were boiled down to 15 cub. centims., then diluted with water to 75 cub. cen- tims., and tested with the normal potash solution ; 23'4 cub. centims. of this solution were found necessary to neutralize it. Any decomposition must have been very slight, as the difference between the volumes of the potash solution added before and after the boiling was only of about 1 cub. centim. As a further proof that the acid is not volatile, I distilled a sample of it in a retort, in the free flame, carrying on the operation until nothing but a dark semifluid mass remained in the retort. The distillate was just faintly acid to the most delicate test paper. In most of my experiments the acid was slightly coloured, and evolved a urinous smell when hot. Under the impres- sion that this odoriferous substance might be a volatile acid, such as those discovered by Stadeler *, I was led to examine very carefully the distillate obtained as above. This fluid had a strong smell of urine and the faintest acid reaction. After the fluid was rendered alkaline by baryta, the smell was in no way diminished ; so that it could not be owing to an acid ; more- over, considering that the colloid acid loses its colour, and apparently in a great measure its odour, after agitation with animal charcoal, we may infer that the odour of urine is owing to a very slight decomposition of the col- loid acid which takes place under the influence of heat, and more especially in the presence of free mineral acids. Returning to the solution of the colloid acid in water : after concentra- tion by heat its colour darkens and it becomes syrupy, with a sharp acid taste, and a slight acrid and astringent after-taste. This taste is percepti- ble in the solution, even when very dilute. I could never obtain any crystals in this syrup beyond those resulting from inorganic impurities. When dried, the acid assumes the form of a transparent varnish, which, by a temperature of 120° Cent., becomes much darkened. The dried * Annal. der Chemie und Pharm. vol. xcvii. p. 134. B 2 Dr. Marcct on a Colloid Acid of Urine. [1864. substance is very 'hygroscopic, and dissolves readily in water (with the ex- ception of some few dark flakes) after exposure for some time at 120° Cent. Alcohol, sp. gr. 827, gives it a dull, opaque appearance, and slightly dis- solves it. The dry acid is insoluble in ether, and its solution in diluted alcohol is rendered turbid by ether. When burnt it chars, emitting a pungent smell ; the ignition is attended with but a very faint flame, show- ing that very little hydrogen enters into its composition ; nothing but a trace of fixed inorganic residue remains after complete incineration of the acid. The colloid acid was found to have no action on polarized light ; it failed to precipitate egg-albumen, but precipitated casein in milk ; the pre- cipitate was not redissolved in an excess of the acid, as in the case of acetic acid ; although strictly a colloid, it passes through the diaphragm of a dialyzer, but the phenomenon is not near so rapid as in the case of crys- talloids. In an alkaline fluid, however, the acid (under the form of a compound) does not find its way so readily through the dialyzer, and its passage is thereby checked in a considerable degree. The qualitative composition of the colloid acid of urine was obtained by subjecting to analysis its insoluble lead-compound. I found the organic substance to consist only of carbon, hydrogen, and oxygen. I have not yet determined the ultimate quantitative composition of the acid, but have succeeded in showing that it possesses an atomic weight, or com- bining proportion, thereby proving the acid to be a definite substance ; the atomic weight of the acid was determined by the analysis of its inso- luble lead-salt and of its baryta-salt. In order to analyze the insoluble lead-salt, a weighed quantity of the compound, dried at 120° Cent., was dissolved in acetic acid, and precipitated by means of sulphuric acid, with the addition of alcohol ; the sulphate of lead was collected in a filter, the filter burnt, and the inorganic residue treated with sulphuric acid ; the sulphate of lead was finally weighed. TABLE showing the results obtained from the analysis of the insoluble lead-salt of the Colloid Acid of Urine. Six sam- ples of the acid. Weight of lead-com- pound ana- lyzed. Weight of protoxide of lead found. Protoxide of lead in 100 parts of the com- Acid in 100 parts of the compound. pound. Exp. grm. grm. t(i 0-223 0-298 0-146 0-2006 65-5 67-3 34-5 32-7 Average 66-4 Acid... 33-6 Mi 0-6575 0-516 0-4250 0-338 64-6 65-5 35-3 345 Average • 65-0 Acid... 35-0 f A. 0-3735 0-2360 63-2 36-9 " 64-2 ' 1 B 0-2835 0-1850 65-3 34-7 Average Acid... 35-8 IV 0-5327 0-3552 66-6 33-4 V 0-612 0-5493 66-1 33-9 VI 0-7183 0-6828 69-9 31-1 100-0 1864.] Dr. Marcet on a Colloid Acid of Urine. 5 Five out of the six analyses were made with the acid slightly coloured, to avoid possible inorganic impurity from the use of animal charcoal. In analysis No. VI. the acid had been treated with animal charcoal, and in this case the percentage of lead was a little higher. It is possible that 33*7 is not the exact percentage of acid in the insoluble lead-compound, although it cannot he far from correct ; but when the difficulty of obtaining the lead- precipitate in a pure condition is taken into account, I think it will be admitted that the results of these analyses approach each other closely enough to show that the lead-precipitate of the colloid acid is a definite chemical compound. Adopting the number 33- 7 as the percentage of acid, the equivalent weight of the acid and of the compound will be PbO 111-57 Acid 56-/0 atomic weight of acid. 168-2 atomic weight of compound. To prepare the baryta-compound of the colloid acid, I began by de- composing with sulphuric acid a known weight of the lead-salt ; and by pro- ceeding as in the case of the analysis of the lead-compound, the amount of the colloid acid present was determined. The acid was entirely washed through the filter along with some free sulphuric acid, and I treated the acid filtrate with carbonate of baryta, the mixture being heated for four or five hours, and filtered the next day ; the precipitate on the filter was finally washed with hot distilled water for from four to six days, and even after this lapse of time the washings still contained a trace of baryta. I shall only report two out of several of these analyses, as in the others the de- ficiency of baryta dissolved was obvious. I have calculated the atomic weight of the acid from the baryta-compound which yielded most baryta, as follows — Analysis No. I. per cent. Compound of colloid acid and f BaO 0-4607 .... 72'2 baryta 0-6382 1 Acid 0-1775 .... 27'8 100-0 Analysis No. II. Compound of colloid acid and f BaO 0-5950 65'7 baryta 0-9058 \Acid 0-3108 34-3 100-0 The atomic weights derived from analysis No. I. are — BaO .• 76-39 Acid . . .... 29-5 Compound 106-0 6 Dr. Marcet on a Colloid Acid of Urine. [1864. If we now compare the atomic weight of the acid in the baryta-com- pound (29(5) with that in the lead-compound (56'7), it will be readily seen that the relative proportion of these two numbers being very nearly one to two, the lead-compound contains two equivalents of colloid acid (2 x 28'3), and the baryta-salt one equivalent of the acid (28*3) ; the insoluble lead- compound is therefore an acid salt of the colloid acid. I shall propose the number 28'3 as the atomic weight of the new acid. "We are now able to explain why the insoluble lead-salt of the colloid acid is soluble in an alkaline fluid such as potash. Of the two equivalents of colloid acid, one combines with oxide of lead, and the other with potash, forming two soluble neutral salts, PbO . 2 acid+KO=PbO . acid+KO . acid. Compounds of the Colloid Acid of Urine. Lead-salts. — Basic acetate of lead added to the free acid, or solutions of its neutral salts, gives rise to a white precipitate. When a glass rod moistened with a solution of basic acetate of lead is immersed into a mode- rately strong solution of the free acid, a precipitate forms, which disappears on agitating the fluid ; this can be repeated several times before the pre- cipitate becomes permanent. When the fluid no longer turns clear on agitation, the application of heat will dissolve the precipitate, but on the further addition of the precipitant, the hot liquid will soon remain turbid. An excess of basic acetate of lead redissolves the precipitate ; this re- solution appears to take place more readily when an excess of the precipi- tant is added to neutral salts of the colloid acid, than when added to the free acid. After mixing basic acetate of lead with urine, treated as described above, and filtering, I observed that the filtrate still contained much organic matter, although the further addition of the reagent caused no turbidity. I at first naturally thought that this was owing to the presence of another colloid substance in urine ; but my surprise was very great when I found that the pure acid obtained by decomposing its insoluble lead-compound could be but partly re-preeipitated by means of basic acetate of lead, a comparatively large portion of organic matter remaining dissolved, as shown by evaporating a few drops of the fluid and incinerating the residue, which charred and burnt away, leaving a little oxide of lead on the spatula. Having previously ascertained that the pure basic lead-salt was nearly perfectly insoluble in water, I could not for some time explain the phe- nomenon. On reflecting upon the fact, it occurred to me that, as the liquor in which the acid had been precipitated appeared to contain some neutral acetate of lead*, possibly this salt had the power of dissolving the preci- * The formation of this compound might be considered to have taken place as shown in the following equation : — PbO] PbO LCrH,0,+4 acid*=2 (PbO, 2 acid)-fPbO, C, H,0,. PbOj 1864.] Dr. Marcet on a Colloid Acid of Urine. 7 pitate ; and on mixing some of the precipitate with a solution of neutral acetate of lead, and boiling, I observed a solution of the colloid compound to take place. This experiment, repeated several times with different samples of the insoluble lead-compound of the colloid acid, yielded invari- ably the same result : although it happened in most cases that the preci- pitate was not entirely dissolved, it was very obvious that the greater portion of it had disappeared. The phenomenon in question is very interesting, not only because it accounts partly for the fact that basic acetate of lead does not precipitate the whole of the colloid acid of urine, but also because it affords additional proof of the insoluble lead-compound being an acid lead-salt of the colloid acid. A piece of wet blue test-paper is reddened when held over the opening of a test-tube in which the mixture of the precipitate and neutral acetate of lead is being boiled, showing that acetic acid is given off. This would not happen unless there was an acid present to displace the acetic acid from the neutral acetate of lead ; and this acid must be the acid lead-salt. There is now no difficulty in ac- counting for the solution of the acid lead-salt in neutral acetate of lead : one equivalent of the colloid acid combines with one equivalent of lead of the neutral acetate, two equivalents of neutral lead-salt of the colloid acid being formed, PbO . 2 (acid) + PbO C4H3O3=2 (PbO.acid) + C4H3O3, while free acetic acid is evolved. On incinerating the acid lead-salt of the colloid acid, it chars and leaves a residue consisting of metallic lead. By boiling the free acid with a small quantity of hydrated oxide of lead, I have often been surprised at the small proportion of lead dissolved, which is apparently owing to the lead being entirely transformed into the insoluble acid salt. After being boiled with a larger quantity of the oxide and filtered, still acid, a precipitate takes place in the fluid on cooling. This precipitate must be a lead-salt of the acid. I have not determined its quantitative composition. With an excess of hydrated oxide of lead, the colloid acid forms a compound in a great measure insoluble in hot water. After boiling the colloid acid with hydrated oxide of lead, it was observed that a yellowish- green crystalline deposit had formed in the capsule ; these crystals, on being burnt, appeared to contain but traces of organic matter. I have not yet been able to determine their nature ; but it is difficult to believe them to be a compound of the organic acid with lead, this acid being strictly colloid in all its other properties. When a solution of the salts of the colloid acid is boiled with hydrated oxide of lead, a portion only of the acid is precipitated ; so that this method is not available for the extraction of the acid from urine. When the colloid acid is boiled with peroxide of lead, some lead is dis- solved, and the solution becomes neutral, or but very faintly acid. The acid dissolves silver from the carbonate, but it is not possible to neutralize it completely thereby. When boiled with black oxide of copper, some copper is dissolved by the colloid acid. The Baryta-Salt. — When the colloid acid of urine is boiled with carbo- 8 Dr. Marcet on a Colloid Acid of Urine. [1864. nate of baryta, carbonic acid is evolved, the fluid becomes neutral, or very sligbtly alkaline, and is found to contain baryta. If the insoluble lead-salt of the acid be decomposed with sulphuric acid, and the filtrate from the sul- phate of lead boiled with carbonate of baryta, the fluid becomes more deci- dedly alkaline. The analysis and composition of this baryta-salt has been given above ; the solution in a syrupy condition deposits no crystals. The concentrated solution of the baryta-compound behaves as follows with reagents. Basic acetate of lead : — A bulky precipitate soluble in an excess ; the precipitate reappears on addition of dilute nitric acid ; the further addi- tion of nitric acid redissolves it. Neutral acetate of lead : — A slight precipitate. Nitrate of silver : — A slight precipitate readily soluble in nitric acid. "When the baryta-salt is boiled with carbonate of silver, but a small pro- portion of the metallic carbonate is decomposed even after long-continued boiling. Acid nitrate of mercury : — A white precipitate becoming darker after a short time. Tannic acid : — A slight precipitate. It should be understood that the more concentrated the solution, the more abundant are the precipitates. The Lime-Salt. — The lime-salt exhibits the same characteristic reactions as the baryta-salt ; it is formed by boiling the free acid with precipitated carbonate of lime. The fluid remained acid after it had been boiled with pounded marble, although some lime was dissolved ; concentrated to a cer- tain point, the solution becomes thick and syrupy, but deposits no crys- tals ; ammonia and oxalate of ammonia do not appear to precipitate com- pletely the lime from the solution, but the precipitation is perfect by means of sulphuric acid and alcohol. The Potash- and Soda-salts, — We may infer from the earthy salts that the potash- and soda-compounds of the colloid acid of urine have a slightly alkaline reaction. There is no difficulty in neutralizing a given volume of the colloid acid with a potash solution, but it is questionable whether a definite chemical compound is thus obtained. Physiological Relations of the Colloid Acid of Urine. I have invariably found the colloid acid present in the urine, but its mode of extraction described above is calculated to give us but a verv rough insight into the quantity naturally contained in the secretion. After decomposing the lead-precipitate 'by sulphuretted hydrogen, a process which it must be remembered is a slow one, a given proportion of the fluid may be evaporated to dryness, the residue dried at between 101° and 110° Cent., and its weight ascertained ; the result will be obtained somewhat more accurately by determining the ashes of the residue, and subtracting this weight from that of the residue. I have extracted from 8 litres of 1864.] Dr. Marcet on a Colloid Acid of Urine. 9 urine 4'46 grammes of the colloid acid. This is probably hardly half the quantity contained in that bulk of the secretion. I have some reason to believe that the colloid acid described in this paper is not confined to the urinary fluid, but is found elsewhere in the human body ; indeed its secre- tion by the kidneys shows that it very probably exists in the blood. My experiments on the blood have not yet been carried far enough to enable me to communicate the results obtained from this inquiry. The functions of the colloid acid of urine while in the blood, assuming that it enters into its composition, must be very important. There can be little doubt that it is intimately connected with the secretion of gastric juice, by displacing the hydrochloric acid of the chloride of sodium in the blood, and transforming the soda into a colloid salt, which, from its colloid nature, would be retained in the blood, while the free hydrochloric acid would pass into the stomach to form gastric juice. I have undertaken an experiment in connexion with this point, which showed that, after dialyzing for five hours a mixture of chloride of sodium and of the colloid acid of urine, the hydrochloric acid had nearly entirely passed through the dialyzer, while rather less than half the amount of the colloid acid had remained on the diaphragm, holding some soda, though a small quantity, in solution ; from an accidental omission in my notes, I regret being prevented from giving the details of the experiment. The free colloid acid being capable to a certain extent of passing through a membrane, its secretion by the kidneys, urine being generally acid, is easily accounted for. As to the mode of formation of the colloid acid of urine in the human body, we have, so far, no positive knowledge. From its composition and colloid nature, it may probably be derived from some transformation of the colloid non-nitrogenous product of the liver, known as the glucogenic substance. Neubauer and Vogel's book on urine contains an account of the mode of preparation and characters of four organic acids discovered in this secretion by Stadeler, these substances being phenylic, taurylic, damaluric and damolic acid. They are obtained from urine by distillation, and are crystalloids, and therefore can have no relation to the substance I have described in this paper. When better acquainted with the chemical composition and physio- logical relations of the colloid acid of urine, I shall be able to give it an appropriate name. 10 Prof. Everett— Observations of [Jan. 12, January 12, 1865. Major-General SABINE, President, in the Chair. The following communications were read : — I. "Account of Observations of Atmospheric Electricity at King's College, Windsor, Nova Scotia."— No. II. By JOSEPH D. EVERETT, M.A., F.R.S.E., Professor of Mathematics in King's College, N.S. Communicated by Professor WILLIAM THOM- SON, F.R.S. Received December 21, 1864. My former paper* embraced the six months from October 1862 to March 1863. Since the latter date my observations have been continued as before, the water-dropping method being employed until December 1st, since which time burning matches have been used, as in the previous winter. The glass fibre of the station electrometer remained unchanged till July 31st, when it became loosened from its attachment, and was replaced by a new and much thinner fibre, which has continued in use ever since. From comparisons made with the portable electrometer, in the manner described in my former paper, it appears that the change of fibre has increased the indications in the ratio of 20'2 t.o 3'1. The principal observations have, as before, been made three times a day, namely at 8 or 9 A.M., 2 P.M., and 9 or 10 P.M. ; but additional observa- tions have frequently been taken at other hours, especially during the months of May, June, and July, when they were much more numerous than in any month included in the former paper. Each observation has generally contained five air-readings — the interval between the readings being a minute, until September 16th, since which date it has been only half a minute. I assume that this change cannot affect the mean result, though it may to some extent influence the observed range. It was adopted for convenience, the new fibre being found to admit of more rapid observa- tion than the old. The following is a summary of the results of observations during rain or other downfall, fog, and thunder and lightning — the period included being the eleven months from April 1863 to February 1864. Rain. — With light rain the electricity is generally moderate, sometimes very weak, and sometimes about double the average fair-weather strength. These remarks do not apply to light rain immediately following heavy, the electricity being often as strong during the intervals between heavy rain, and for some time after its conclusion, as during its descent. Very heavy rain is almost invariably accompanied by very strong electricity. Snow. — Almost always positive, but occasionally a little negative inter- mixed with positive ; and on one solitary occasion (February 1 6th) strong negative sparks were drawn during a heavy fall of snow. On this occasion strong positive electricity was also observed. It is worthy of remark that * Read June 18, 1863, Proceedings, vol. xii. p. 683. 1865.] Atmospheric Electricity. 11 on the following morning and midday strong positive sparks were drawn, and the electricity continued very strong positive during the remainder of the day. No snow fell, but a strong west wind filled the air with drifting Hail. — I have nothing to add under this head, except that on one occa- sion (February 26th) strong positive sparks were drawn during hail 'accom- panied by lightning and thunder. Sleet. — One observation : rather strong negative. Fog. — Always positive, and generally above the average strength, but sometimes rather below. The fogs embraced in this account were few and inconsiderable, never lasting more than a few hours, whereas the former paper included some of a more decided character. Thunder-storms.' — None of these occurred during the period embraced by the former paper ; but there have been several since, and always marked by very strong electricity. The first occurred June loth, distant thunder commencing about 1 P.M., and a violent thunder-storm continuing from 4h 30™ to 6h P.M. with a deluge of rain, three-quarters of an inch falling in half an hour. Silent lightning continued all the evening, and to an unknown hour in the night. The electrometer showed, as usual, moderate positive, while the thunder was distant; but observations from 4h 36m to 6h 2m showed electricity exces- sively strong, with frequent changes of sign. The extremes were +104 and —121, the average fine- weather strength being 3 or 4. The next storm occurred June 24th. Observations were taken from 5h 1 lm to 5h 39m P.M., during which time much thunder was heard, but no lightning seen. The electricity observed was constantly negative, increa- sing by a nearly regular advance from — 29 to — 214, this last being the strongest electricity that I have ever yet found. No rain fell during this observation, but '39 of an inch fell before 9 P.M., with some heavy peals of thunder and vivid lightning. Immediately after the heaviest peal strong negative electricity was found, but was not measured. On the evening of July 6th there was much silent lightning, the flashes being at the rate of four or five a minute, some of them very vivid. The electricity observed was weak, never rising higher than 1-8. The next storm occurred July 18th, and closely resembled that of June loth, but on a reduced scale as regarded its external features. The indi- cations of the electrometer, however, were quite equal in strength to those observed on that occasion. The next day (July 19th) there was distant thunder and lightning, with what appeared to be rain in the distance, from about 3 to 4 P.M. ; and the electricity observed was very strong negative, observations extending from 3h llm to 3h o/m. The observations on these two days are given in extenso at the end of this paper. Silent lightning was observed on the evening of August 6th, the electri- city indicated being moderate positive. On August 10th there was a deluge of rain with some thunder and light- 12 Prof. Everett — Observations of [Jan. 12, ning, during which frequent observations were taken, showing very strong electricity, generally negative. No more instances occurred till the evening of February 26th, when hail fell, with short intermissions, from a little before 9h 30m P.M. till after mid- night, accompanied by much lightning and some thunder. The only obser- vation of the electrometer was at 9'1 30m, when strong positive sparks were obtained. It appears from these instances, that thunder-storms in the neighbour- hood of the place of observation are accompanied by extremely strong indications of atmospheric electricity, but that neither silent lightning nor the distant rumbling of thunder is accompanied by any marked effect on the electrometer. For the sake of comparison with numerical data given in the former paper, applying to the six months October 1862 to March 1863, I subjoin the corresponding data for April to September 1863, thus completing a year from the commencement of observations. Positive only. Negative only. Both kinds. Days. Days. Days. Rain .................. 17 7 12 Snow .................. 1 0 2 Hail .................. 1 1 0 Fog .................. 3 0 0 Thunder or lightning ---- 2 2 3 There were 34 days on which both positive and negative electricity were observed ; and on 29 of these, rain or other downfall occurred. The remaining 5 days, with the strongest negative observed, and the state of cloud and wind at the time, were as under (the scale for cloud being 0-10, and for wind 0-6). May 31. —0-4 June [12. —0-4 July 15. -0-8 Aug. 24. -1-0 10 nim. 10 all sorts. _ fnim. \ intensely black. 10 St. 9 cu.-st. 1 S.W. 1 N.E. 4 / N'W- \ a brief squall. 1 N. 1 S.W. It will be observed that in all these instances the weather was cloudy and the negative electricity weak, characteristics which also belong to the corresponding instances* in the former paper. The remark there made, that on every day on which negative electricity had been observed, positive had also been observed, holds good down to the present date (March 1864). The monthly means of the results of fine- weather observations, for dif- ferent hours of the day, from April to September 1863, are shown in the following Table. They have been computed in the same manner as the corresponding numbers in the former paper. 1865.] Atmospheric Electricity. 13 April. May. June. July. August. September. Hour. Nr. Nr. Nr. Nr. Nr. Nr. of ob- serva- Mean. of ob- serva- Mean. of ob- serva- Mean. of ob- serva- Mean. of ob- serva- Mean. of ob- serva- Mean. tions. tions. tions. tions. tions. tions. 6 to 7 A.M. 1 2-20 2 3-80 1 3-39 7 to 8 5 4-82 2 3-40 8 3-28 7 4-16 5 4-40 12 3-85 8 to 9 16 4-46 19 3-15 16 2-94 18 3-06 12 3-90 7 3-63 9 to 10 3 4-37 11 2'80 8 2-95 13 3-34 4 4-54 4 4-75 10 to 11 2 5-70 3 2-27 4 2-60 12 2-88 7 4-10 1 5-00 11 to 12 4 3-10 2 2-95 2 2-10 10 2-71 2 2-33 12 to 1 P.M. 4 4-15 3 3-30 4 2-60 8 3-32 5 4-52 1 4-96 1 to 2 9 4-31 3 3-57 9 3-29 19 3-10 10 3-80 8 4-75 2 to 3 14 4-92 19 3-47 15 2-88 10 3-12 7 3-99 8 4-13 3 to 4 ... ... 3 3-93 6 2-94 10 3-23 2 4-51 2 2-78 4 to 5 6 3-77 7 3-50 6 3-17 9 3-60 2 335 1 7-62 5 to 6 5 3-84 8 3-69 5 3-22 9 2-92 2 4-05 4 4-15 6 to 7 4 4-02 5 3-48 5 3-02 9 3-86 6 3-27 7 to 8 3 3-50 3 3-83 3 3-10 6 2-33 6 4-75 8 to 9 1 1-50 1 3-80 3 3-33 3 3-00 3 3-25 9 to 10 12 s'-'is 22 2-97 21 2«9 14 1-93 8 2-60 11 3-39 10 to 11 4 2-80 3 2-17 4 2-40 12 2-01 4 3-29 3 2-46 11 to 12 P.M. 2 3-35 6 1-70 3 2-97 1 2-90 3 1-96 1 2-80 12 to 2 A.M. 1 2-20 1 4-60 4 1-63 ... 2 2-77 Sums and 1 94 4-08 121 3-13 125 2'83 172 3-01 91 3-71 G6 3-92 means. J '" For the whole six months we have the following results : — Hour. Number of observations. Mean of all observations. Mean of monthly means. 6 to 7 A.M. 4 3-30 3-13 7 to 8 39 3-96 3-98 8 to 9 88 3-47 3-52 9 to 10 43 3-44 3-79 10 to 11 29 3-33 3-76 11 to 12 20 2-71 2-64 12 to 1 P.M. 25 3-64 3-81 1 to 2 58 3-69 3-80 2 to 3 73 3-70 3-75 3 to 4 23 3-33 3-48 4 to 5 31 3-64 4-17 5 to 6 33 3-51 3-64 6 to 7 29 3-55 3-53 7 to 8 21 3-51 3-50 8 to 9 11 3-11 2-98 9 to 10 88 2-71 2-74 10 to 11 30 2-40 2-52 11 to 12 16 2-33] 2-61 12 to 2 A.M. 8 2-38 2-81 Means of 1 columns]"'" ... 3-45 3-38 Hence there appears to be a maximum soon after sunrise, a decided minimum between 11 and 12, and a maximum (less clearly marked) between 4 and 5 P.M., followed by a regular decrease to midnight. These 14 Prof. Everett — Observations of [Jan, results agree very well with those derived from the previous six months, allowing for the difference between the length of the day in summer and in winter. The following Tahle of the variations of electricity in fine weather, from month to month, embraces the whole period of observation down to Febru- ary 18G4. These results, as well as those above given, are expressed in units of station electrometer with second fibre, being the same unit that was employed in the previous paper. The day is supposed to be divided into three portions — before noon, noon to 6 P.M., and after 6 P.M. For each month, all the observations in each portion have been summed and divided by their number, giving the means shown below. Year. Month. Before noon. Noon to 6 P.M. After 6 P.M. Mean of three preceding columns. 1862. October. 3-42 3-68 2-69 3-26 November. 3-53 2-89 2-58 3-00 a December. 4-09 5-01 2-77 3-96 1863. January. 4-11 4-88 3-42 4-14 February. 6-10 5-77 4-96 5-61 March. 6-28 5-10 5-02 5-47 April. 4-41 4-37 3-26 4-01 May. 2-98 3-54 2-85 3-12 June. 2-91 3-02 2-52 2-82 *July. 3-17 3-20 2-50 2-96 August. 3-98 4-01 3-20 3-73 September. 3-98 4-41 3-18 3-86 October. 5-24 4-16 2-74 4-05 November. 4-24 4-13 2-82 3-72 December. 4-51 5-14 3-39 4-35 1864. January. 3-80 5-74 3-63 4-41 cFebruary. 4-78 4-97 3-16 4-30 a. Second fibre put in December 6th. b. Third fibre put in July 3 1st. c. The electricity on February 17th and part of 18th was out of range, and has not been reckoned. Tbese results show that atmospheric electricity is stronger in winter than in summer, and seem to indicate a double maximum and minimum within the year, — the principal maximum occurring about February, and the other maximum about October ; the principal minimum in June, and the other in November. It will be observed that in every case the numbers in the column " after 6 P.M." are the smallest. At the suggestion of Professor Thomson, I have made a careful compa- rison of the states of electricity, as regards both strength and variableness, for different directions of wind. For this purpose I have tabulated accord- ing to direction of wind (separating also fine-weather from wet-weather observations) the daily entries of mean potential at 2 P.M. for the first twelve months, also the variableness as measured by the difference between the entries of highest and lowest potential for the same hour. Where there was no observation between 3 and 4 P.M. the day was passed over ; 1865,] Atmospheric Electricity. 15 and where more than one observation was entered between these hours, that which was nearest to 2 P.M. was alone reckoned. From these data, the monthly means of strength and variableness were computed; but in neither case was any regularity exhibited. The only results of this comparison which seem worthy of record are the annual fine-weather means (derived from the monthly) for the prevailing directions of wind. These are- Calm. S.W. N. N.W. W. Strength 4'29 3'63 4'03 4'48 4*05 Variableness.. 1-19 '88 1'22 171 '79 I append, by way of specimen, the observations taken on June 29, July 1, 18, and 19. The first two days contain instances of some of the weakest electricity that I have ever found in clear weather (I allude particularly to the observations at 2h 10m June 29th, and at 3h 47m July 1st). The other two days afford fair instances of observations during thunder and lightning*. Electricity. Cloud. Wind. Baro- meter uncor- rected. Thermo- meters. Mean. Highest. Lowest. 0-6. 0-10. Dry bulb. 67-8 78-1 69-4 62-5 65-9 70-4 81-3 66-6 60-6 68-2 77-5 79-3 77-4 77-4 7G-0 Dry above wet. June 29. h m 8 48A.M. 2 10 P.M. 9 27 July 1. 7 31 A.M. 8 20 9 49 3 47 P.M. 8 58 10 29a + 2-1 + 0-5 + 1-8 + 2-3 + 1-8 4- 1-8 + 0-8 + 1-6 + 1-6 + 2-2 + 2-9 + 3-6 - 24-3 - 30-1 - 59-6 - 90-2 -105-4 - 80-3 - 93-6 - 86-8 - 49-4 - 64-3 - 74-2 - 55-9 - 1-2 - 19-5 + 24-1 + 2-2 + 0-8 + 1-8 + 2-3 + 1-9 + 1-9 + 1-0 + 1-7 + 1-6 + 2-3 + 3-0 + 3-8 -20-2 -26-9 -43-9 + 2-1 + 0-2 + 1-7 + 2-2 + 1-7 + 1-6 + 0-5 + 1-4 + 1-5 + 2-1 + 2-9 + 3-4 -27-6 -32-4 -76-9 0 2 0 0 0 0 0 1 0 1 5 2 9 }• 1» 'c'uV "stl" Cu. Cu.&st. Cu. ^im.&cu Nim. 0 2 0 0 0 0 1 0 0 0 0 1 1 1 Calm. N. Calm. Calm. • S.W. Calm. Calm. N.W. N.W. N.W. 30-05 30-03 30-07 30-12 30-12 30-11 30-08 30-12 30-12 30-28 30-28 30-27 30-26 30-26 30-27 3-8 7-8 3-6 2-5 4-0 7-1 12-1 5-3 3-3 1-9 4-3 5-8 4-3 4-0 3-2 Julv 18. 8 16A.M 11 58 1 51P.M 3 216 3 40 3 49 3 59 4 0 4 1 4 2 4 3 4 3* 4 4 4 6 4 7 4 8 4 9 4 10 ( Moderate \ rain ... / Pouring [ rain ... Light rain. Rain hcavv [rate Rain mode Peal overhead. [head Rumblingover «. Aurora. b. Continuous rumbling of distant thunder in N.W., lasting till 5 P.M. * The details of daily observations from April 1, 1863, to February 28, 18G4, inclusive, are given in a series of Tables which are preserved for reference in the Archives. 16 Observations of Atmospheric Electricity. TABLE (continued}. [Jan. 12, Electricity. Rain. Cloud. Wind. Baro- meter uncor- rected. Thermo- meters. & Dry above wet. Mean. Highest Lowest. 0-6. 0-10. July 18. h m 4 lO^p.M 4 11 4 12 4 12* 4 14 4 15 4 16 4 17 4 17£a 4 18 4 19 4 19* 4 20 4 24 4 25 4 33 4 34 4 35 4 37 4 38 4 39* 4 40 4 41 441* 4 42 443 4 44 4 45 5 8 6 7 8 8 10 0 The wea July 19. 9 49A.M. 1 3£p.M. Thunder 3 11 P.M. 3 12 3 13 3 16 3 22 3 32 3 35 3 57 4 12 9 18 - 18-5 - 45-7 -111-0 - 81-9 -146-0 -138-0 -120-0 -107-0 -129-0 - 61-8 - 74-2 - 80-0 - 62-7 - 73-5 + 2-2 - 53-2 - 65-2 - 3-7 - 27-8 + 4-6 - 16-1 - 80-7 -101-0 + 73-2 + 46-4 + 38-0 + 14-8 - 2-2 + 24-7 + 5-7 + 3-8 + 1-8 ther has + 6-1 + 3-1 and ligh - 34-9 - 38-3 - 37-1 - 20-7 - 23-5 - 17-0 - 16-7 - 20-1 - 9-9 + 2-4 Flash. Heavy peal. [rate. Rain mode- Heavy rain. Pouring „ [rain. [rain. Pouring [rate. Rain mode- Rain light. 30-28 30-29 30-30 30-30 h. 30-29 30-23 | 30-2C igin> urently 30-20 30-20 74-7 75-9 75-4 69-2 170-6 76-2 174-5 r.w. rain- ,« C8-C 2-8 2-7 2-7 1-3 1 2-0 j 3-5 1 2-9 3, H Flash. Heavy thun- [tinuous. Thunder con- [overhead. Heavy clap +25-9 + 5-8 + 3-8 + 2-0 >een ex + 7-2 + 3-5 tning in +22-8 J- 5-5 + 3-8 + 1-5 remely + 5-0 + 2-9 W. am | oppressive a 1 :::::: 1 N.W. API 6 7 9 Iday. 10 3 mrentl I 9 5 here, Cu. &c. 0 Cu.-st.&c. 0 Nina. 1 Amount of rain Nim. 1 1 Cu. & ci. | 0 y raining there. |Nim.&cu.| ... but thundering i Calm. N.W. •31 inc N. Calm. a P nd app< Raining. Not rainin N.W. Thundering in Flash in N.W. Thund + 2-8 erinN.E + 1-81 8 10 Nim.&cu. Nim. &c. 2 0 N. Calm. a. Continuous rumbling of distant thunder till 5 P.M., followed by occasional distant thunder till about 5h 15»n P.M. I. Excessively close. 1865.] On the Acids of the Lactic Series. 17 II. "Notes of Researches on the Acids of the Lactic Series. — No. II. Action of Zinc upon a Mixture of Iodide of Ethyl and Oxalate of Methyl." By EDWARD FRANKLAND, F.R.S., and B. F. DUPPA, Esq. Received December 20, 1864. In our former communication * on the action of zinc upon a mixture of iodide and oxalate of methyl, we described a process by which the use of the zinc-compounds of the alcohol radicals may be dispensed with in the production of the series of acids which we are now investigating. We then described this process as being conducted at a temperature of 70° to 1 00° Cent, for twenty-four hours, until the mixture had solidified to a yellow- ish gum-like mass, which on distillation yielded a mixture of water, alcohol, and the ether of the new acid. Subsequently we have found it more ad- vantageous to continue the operation for a much longer time at a lower temperature, thereby obtaining a crystalline instead of a gum-like pro- duct, the former giving a much better result as regards the production of ether. In the reaction which forms the subject of the present Note, we have proceeded in the following manner. Two atoms of iodide of ethyl were mixed with one of oxalate of methyl and placed in a capacious flask, with zinc in sufficient quantity to be barely covered by the ethereal mixture. We prefer to use zinc which has been employed in a previous operation, as we find it to act not only with greater rapidity, but also at a much lower temperature. The time required for the completion of an operation is about ninety-six hours at a temperature of from 30° to 50° Cent. During the first eighteen or twenty hours no apparent action takes place, the liquid remaining perfectly limpid, and the zinc apparently untouched ; but after this period a straw-coloured tint gradually makes its appearance and slowly increases in intensity, until the liquid solidifies to a mass of crystals which scarcely fuse at 50° Cent. The operation may now be con- sidered as ended, although a considerable quantity of the mixed ethers is still unacted upon. Water being now added by slow degrees until it equals three times the volume of the crystalline mass, a copious effer- vescence takes place ; oxalate and oxide of zinc are formed in abund- ance, whilst, on the application of heat, alcohol, accompanied by a con- siderable quantity of an ethereal body, distils over along with the iodide of ethyl that has not been acted upon. The addition of water to the distillate effects an approximate separation of the ethereal from the alco- holic portion ; the former is then decanted and distilled for the purpose of separating alcohol and iodide of ethyl. When the temperature of ebullition rises to 100° Cent., the liquid left in the retort is placed over chloride of calcium for twelve hours, after which it is again submitted to distillation, when its boiling-point almost immediately rises to 165° Cent. * Proc. Roy. Soc. vol. xiii. p. 140. 18 Frankland and Duppa — Adds of the Lactic Series. [Jan. 12, (bar. 29'85 in.), at which temperature the whole of the remaining liquid passes over. Submitted to analysis, this liquid yielded results closely corresponding to the formula C7H1408. The decomposition of this ether by baryta, described below, proves it to be the methyh'c ether of an acid of the same composition as leucic acid, with which also it agrees in its fusing-point. The composition of this ether may therefore be thus expressed : — OCH3 Leucate of methyl is a colourless, transparent, and tolerably mobile liquid, possessing a peculiar ethereal odour only remotely resembling leucate of ethyl. It is very sparingly soluble in water, but readily soluble in alcohol or ether. Its specific gravity is -9896 at 16°-5C. ; it boils at 165° and distils unchanged. A determination of its vapour-density gave the number 4 -84, the above formula corresponding to two volumes of vapour (H2 O=2 vols.) requires the number 5 -03. Treated with caustic alkaline bases this ether is readily decomposed, even in the cold, yielding methylic alcohol and a leucate of the base. A quan- tity of it was thus decomposed with solution of baryta, the excess of the base being afterwards removed. It yielded on evaporation a crystalline mass very soluble in water, alcohol, and ether, and which, on analysis, yielded results closely corresponding with those calculated from the formula of leucate of baryta. When this baryta-salt in aqueous solution is decomposed with the exact amount of sulphuric acid necessary, the liquid filtered off from the sulphate of baryta, and evaporated in vacua, the acid crystallizes magnificently. Professor "W. H. Miller has kindly undertaken the determination of the angles of these crystals. They are readily soluble in ether, alcohol, and water. The acid is greasy to the touch, and nearly inodorous. It sub- limes readily at 50° C., and slowly even at common temperatures, a small quantity of the acid left on a watch-glass gradually disappearing, though in other respects it is permanent when exposed to the air. It fuses 1865.] Messrs. Buckton and Odling on Aluminium Compounds. 19 at 74°- 5 C. Numerous analyses furnished the numbers required by the formula OH Leucate of silver was made by adding oxide of silver to a hot solution of the acid. After filtration and evaporation in vacua, it crystallizes in brilliant silky fibres adhering closely to the capsule. These are anhydrous, and are scarcely discoloured by prolonged exposure to a temperature of 100° C. They yielded on analysis numbers closely corresponding with those calculated from the formula Although this acid possesses the same percentage composition, atomic weight, and fusing-point as the leucic acid obtained by the action of zincethyl upon oxalic ether, yet it does not appear to be identical with that acid. The silver-salt of the latter crystallizes in brilliant needles radiating from centres standing up freely from the capsule, and containing half an atom of water which is not expelled at 100° C. This salt also further differs from that above described by becoming rapidly discoloured when exposed to the heat of a steam-bath. We are at present engaged with a rigorous comparison of the properties of these and other similarly related acids of the lactic series. III. " Preliminary Note on some Aluminium Compounds." By GEORGE BOWDLER BUCKTON, F.R.S., and WILLIAM ODLING, M.B., F.R.S. Received January 12, 1865. Until recently the molecule of aluminic chloride had always been repre- sented by the formula A12 C13, or, selecting the high atomic weight of alu- minium, as required by its specific heat, Al C13. But since Deville's deter- mination of the vapour-densities of aluminic and ferric chlorides, many chemists of eminence, both in this country and abroad, have adopted the formula A12 C16, and have consistently doubled the previously received for- mulae for the entire series of aluminic compounds. In our opinion, how- ever, the hitherto existing data seemed hardly sufficient for the definitive establishment of either set of formulae ; and it occurred to us that an exa- mination of the so-called organo-compounds of aluminium might not im- probably throw some important light upon the question at issue between them. We regarded the determination of the question as a matter of con- c 2 20 Messrs. Buckton and Odling on Aluminium Compounds. [Jan. 12, siderable interest from the bearing it would necessarily have upon the posi- tion of aluminium in a natural classification of the elements ; upon the molecular formulae of chromic, ferric, cuprous, and perhaps mercurous compounds j and consequently upon Laurent and Gerhardt's general law of even numbers. Moreover a satisfactory investigation of the organo- compounds of a metal certainly not belonging to any one of the recognized classes of metals with whose organo-compounds chemists have become familiar, seemed likely to furnish a useful contribution to the common know- ledge of organo.metallic bodies. Cahours, in an admirable paper on the organo-compounds of tin, published early in 1860, observed incidentally that aluminium was attacked by the iodides of methyl and ethyl at the temperatures 100°-130°, and that the crude ethylated product reacted violently with zinc-ethide to form a very inflammable liquid, which was doubtless aluminium ethide. Our experiments in confirmation of Cahours's results have been as yet merely preliminary ; but by acting on aluminium with mercuric methide and ethide at the temperature of 100°, we have ob- tained pure aluminium methide and ethide without difficulty, and in not inconsiderable quantity. This mode of experiment was obviously suggested by Frankland and Duppa's recently described processes for making methide and ethide, and for transforming these compounds into zinc methide and zinc ethide respectively. Aluminium Ethide. Mercuric ethide with excess of aluminium-clippings contained in sealed tubes was heated for some hours in a water-bath, when the mercury was found completely displaced by the aluminium, thus, A12 + 3 Hg Et2= Hg3 + 2A1 Et3, or AL, Et6. After distillation off fresh aluminium and rectification in an atmosphere of hydrogen, the resulting aluminium ethide boiled steadily at 194°. It occurred as a colourless mobile liquid, which did not solidify at uthe tempe- rature of — 18°C. It evolved dense white fumes on exposure to air, and when in thin layers took fire spontaneously, burning with a bluish red- edged flame, and producing an abundant smoke of alumina. On analysis it yielded 61 '4 per cent, of carbon, 12'9 per cent, of hydrogen, and 24-0 per cent, of aluminium, numbers which accord reasonably well with the formula Al Et3, or A12 Ete, the carbon and hydrogen being slightly deficient from some unavoidable oxidation of the substance analyzed. Its vapour- density, taken by Gay-Lussac's process at the temperature 234°, was found to be 4-5, the theoretical density calculated for the formula AlEt3 being 3'9, and that for the formula Al2Et6 being of course 7'8. Hence alumi- nium ethide would appear to have the simple molecular formula Al Et3 ; for the difference between the experimental number 4*5 and the theoretical number 3*9, is an obviously necessary consequence of the extreme oxidiza. bility of the compound. Water effected a complete decomposition of alu- minium ethide with explosive violence. Iodine reacted upon it, to produce iodo-derivatives and iodide of ethyl. Oxygen in the form of dry air was simply absorbed with production of a body apparently analogous to boric 865.] Messrs. Buckton and (Ming on Aluminium Compounds. 21 di-oxyethide. But the iodo- derivatives and oxidation products have as yet been submitted to a preliminary examination only. Aluminium Methide. This compound was obtained by a process strictly analogous to that which yielded us aluminium ethide. On heating mercuric methide with alumi- nium-clippings in a water-bath, the replacement of the mercury by alumi- nium took place with even greater facility than was manifested during the similar treatment of the ethylated body. After a single distillation, alumi- nium methide occurred as a colourless mobile liquid, boiling steadily at 130°, and solidifying a few degrees above 0° into a beautiful transparent crystal- line mass. The liquid took fire spontaneously on exposure to air, burning with a very smoky flame, and producing abundant flocculi of alumina dis- coloured by soot. On analysis, aluminium methide gave 48*4 per cent, of carbon, 12'3 per cent, hydrogen, and 38' 2 per cent, aluminium, numbers which are quite sufficiently in accordance with the formula AlMe3, or A12 Me8. Three separate determinations of vapour-density, made at the temperatures of 240°, 220°, and 220°, the last with hydrogen in the tube, gave the numbers 2-80, 2*80, and 2'81 respectively, which agree closely with the theoretical number calculated for the formula Al Me3, namely 2 '5. But the corrected density increased very rapidly with every decrease of temperature, a peculiarity of behaviour also noticed by Frankland in the case of boric methide. Thus three separate determinations, made at 163°, 160°, and 162°, the last with hydrogen in the tube, gave the densities 4'1, 4'1, and 3'9 respectively; while the determinations made at the boiling- point of aluminium methide, of course with hydrogen in the tube, as re- commended by Playfair and Wanklyn, gave the densities 4'36 and 4'40 respectively, which approximate somewhat to the theoretical density 5'0, calculated for the formula Al2Me8. Hence aluminium methide appears to be a member of that class of bodies whose vapour-densities are under certain circumstances anomalous, either because the bodies exist in two molecular states of condensation, or because their vapours are not possessed of perfect elasticity until heated considerably above the boiling-points of the respective liquids. In either case the question naturally presents itself, May not the only observed vapour-density of aluminic chloride correspond to the high vapour-density of aluminium methide, and may they not both be equally anomalous, and consequently untrustworthy as a basis for deter- mining the general formulae of aluminic compounds? 23 Prof. Guthrie on Bubbles. [Jan. 19, January 19, 1865. Sir HENRY HOLLAND, Bart., Vice-President, in the Chair. The following communications were read : — I. "On Bubbles." By FREDERICK GUTHRIE, Esq., Professor of Chemistry and Physics at the Royal College, Mauritius. Com- municated by Professor STOKES, Sec. R.S. Received December 22, 1864. As it was found necessary, in considering drops*, to define the term, and limit its application, so we must understand once for all in what sense and under what restrictions the term bubble is to be employed. This is the more necessary, because the word bubble is used even more loosely than the word drop. In Plate I. fig. A, 1, 2, and 3 show the meaning of a drop as we have defined and used the expression ; 4 shows the condition of a bubble as it is understood in the following investigation. Under this limitation, a bubble XGLf only differs from a drop XL2 Lj (3, fig. A) in consisting of a gas instead of a liquid. A bubble is a mass of gaseous matter compelled to assume a more or less spherical form by the cohesion and weight of the liquid medium in which it is formed, and sepa- rated from other matter by the action of gravity. Since, under like con- ditions of pressure, all gases are lighter than all liquids, the separating force is the gravity of the medium, as was the case with the drop (3, fig. A). Accordingly, a bubble invariably ascends. Owing to the universal diffusion of gases, no case can exist of a gas-bubble in a gaseous medium (XGG) ; and for obvious reasons a solid medium is inadmissible. So defined, a bubble must therefore invariably be a case of XGL. It is, however, worth while, in passing, to notice the construction of some other bodies which are also called drops and bubbles. Thus all the states of matter shown in fig. B are called, in common speech, drops or bubbles ; and some of them, indeed, are one or the other, according to the aspect in which they are viewed. All of the ten modifications in fig. B are very common : the Nos. 1, 2, 3, 4, 5, 6 are usually called drops ; the Nos. 7, 8, 9, 10 are called bubbles. Nos. 4 and 5 show the two instances of what is called spheroidal state. Nos. 7, 8, 9, 10 are the commonest forms of the soap-bubble. Tbe equations under each figure show the possible identity of two matters of the same kind. All the above ten cases are at once dis- tinguishable from the true drop and bubble by the existence in them of an additional factor, which is not present in the true drop or bubble, namely the cohesion of &film. Such drops and bubbles may therefore be con- veniently distinguished from the true ones of fig. A by being called film- drops and film-bubbles. In the spurious drops 1, 2, 3, 5, the film partly enclosing and restraining the drop is a film of liquid : so also in the bubble * See the author's Memoir on Drops, Proceedings, vol. xiii. p. 444. t Where X is either solid, liquid, or gaseous. fhc. Puy. Soc. Vob.XlV:Plcut&l. Pig A *©" 1865.] Prof. Guthrie on Bubbles. 23 9. In the drops 4, 6, and in the bubbles 7, 8, the restraining film is a gas. There is a remarkable inverse analogy between the cases 4 and 9. In 4 a gaseous film hinders a liquid from reaching a liquid ; in 9 a liquid film hinders a gas from reaching a gas. The cases 7 and 10 are also called, hubbies, although their only title to the name is the liquid film in each. Viewed as film-envelopes, 1, 2, 3, 4, 5, 6 are bubbles ; viewed as spheroidal liquid masses they are drops. Further, the spurious drops and bubbles differ from the true ones which we have to examine in a very important particular. The spurious ones are essentially statical phenomena, and retain their indefinite size for an inde- finite time. The true drops and bubbles, on the other hand, grow until their exact equilibrium is established, and they acquire their definite size at the instant of the overbalancing of that equilibrium — that is, at the instant of their motion. It is, in fact, this overbalancing which determines the definiteness of their size, by withdrawing them from the size-determining effect of the action of the contending forces which accompany and condition their growth. All attempts to get a perfectly uniform succession of bubbles of the pure form SGL (corresponding to water dropping from a glass sphere) failed through the impossibility of getting the immersed solid protected by the gas from the adhesion of the liquid. But by a contrivance similar to that described in the case SLjL^, where Lx was lighter than L2*, it was found possible to get bubbles of uniform size, and to measure them. The most obvious manner of doing this is to force a gas at a fixed rate through an ordinary gas-delivery tube, and to collect and measure a given number of the bubbles in a calibrated tube over the pneumatic trough. This plan, however, is open to the objection of requiring a large quantity of liquid medium. The apparatus employed is seen in fig. C. The quart bottle A is filled a little above the mark a with water, which is in some experiments covered with a film of oil. Through its cork three tubes, C, D, F, pass absolutely air-tight. The tube C is a simple funnel-tube, open near the bottom of A. The tube D also reaches to the bottom of A, and acts as a siphon : its longer limb is narrowed at the point, and delivers its water into the little flask M, whose neck bears a mark m. The shorter limb of D bears a cock E to regulate its discharge. The third tube F, which opens immediately under the cork of A, is fastened by a caoutchouc joint to the tube B. In this joint, and pressing the ends of both tubes, is a compact mass of cotton-wool. B passes through the cork of the little test-tube G, which is divided into millimetres, and contains the liquid through which the hubbies are to pass. Through the cork of G another tube H is passed, whose lower end h is bent out horizontally, and is beneath the surface of the liquid in G ; H is connected by a caoutchouc joint with I, which passes nearly to the bottom of a second little test-tube J. The tube J con- tains a few drops of the liquid which is in G, and the space between I and * On Drops, p. 478. 24 Prof. Guthrie on Bubbles. [Jan. 19, the sides of J is filled with cotton-wool moistened with the same liquid. The last tube K, which opens immediately under the cork of J, is either open to the air, or connected with a gas-bag containing the gas under examination, or fastened to a chloride-of- calcium tube, according to the requirements of the experiment. In some experiments the little tubes G and J are sur- rounded with water contained in the vessel N. The tubes G and J are firmly bound to a flat piece of cork held by the heavy clamp P, which rests on the bottom of N. A thermometer T is placed in the water of N. The apparatus is used as follows : — B and F being disconnected, the bottle A is nearly filled through C. The end of F is closed by the finger, and, the stopcock E being opened, the siphon D is filled once for all by applying the mouth to its longer end. E being then closed, the tube G is filled up to the required mark with the liquid which is to serve as a bubble-medium. The cotton-wool in J is moistened with the same liquid. All the joints are made fast, and the tube K is connected with the gas-bag L. On turning the stopcock E, water flows through the siphon D into the flask M : to supply its place, gas must enter by F ; that is, gas must bubble through the liquid in G. Before entering G it becomes saturated with the vapour of the same liquid in J. If all the joints are tight, it follows that the volume of water entering M is equal to the volume of gas which bubbles through the liquid in G. It is a sufficient test of the tight- ness of all the joints (as far as H), to run off a little water by D, so as to bring a bubble or two of gas through h, and to allow the apparatus to rest. If the tube H remains full of air to its extremity for a quarter of an hour, the apparatus may be considered as air-tight. A metronome is adjusted to beat to the required time. M is removed and emptied. E is turned till the bubbles, passing through the liquid in G, are synchronous with the beats of the metronome. This rate is maintained until the liquid in A sinks to a. The flask M is then put in its place, and from that instant the bubbles through G are counted. When M is filled exactly up to m, the experiment is finished. The proximity between M and G enables the eye to count the bubbles, and to watch without difficulty, at the same time, the rise of the liquid in M. The contents of M, divided by the number of bubbles, gives the mean volume of a single bubble. The use of the cotton- wool in the joint between B and F is to check the flow of gas through the apparatus. When this plug is absent, the considerable volume of gas in the upper part of A, being in direct communication with G, causes by its elasticity an irregular delivery of bubbles through G. Of course as M is filled the level of the liquid in A falls, the difference between the limbs of the siphon D is diminished, the flow through D is retarded, and the bubbles follow one another more slowly. We shall see, however, that the rate of sequence has exceedingly small, or absolutely no influence upon bubble-size. In the experiments actually performed to establish this fact, the metronome was allowed to continue beating throughout the expe- riment, and an occasional tap on the cock E was found sufficient to regu- late the rate of sequence with perfect accuracy. The great comparative 1865.] Prof. Guthrie on Bubbles. 25 volume of A, moreover, prevents the level of its water from undergoing more than a very slight variation during a single experiment. Certain modifications were introduced in the apparatus for special purposes, which will be described in their proper places. Judging by analogy from the results obtained with drops, we should conclude the bubble-size to be influenced mainly by 1. Rate of sequence, or value of fft. 2. Chemical nature of bubble-gas, if homogeneous. Proportion between its constituents, if heterogeneous. 3. Nature of solid from which the gas is delivered. 4. Size of orifice and geometric distribution of solid about its orifice. 5. Temperature of gas and medium. 6. Tension of gas, influenced by natural or artificial causes. 7. Chemical nature of liquid, if homogeneous ; and proportion between its constituents, if heterogeneous. As in the cases of SLG and SLL, the solid serves mainly as a support to the dropping liquid, and influences the size of the drop by the various ways in which it affects the liquid film which adheres to the solid ; the actual disruption being between liquid and liquid : so in SGL the bubble parts in truth from gas. The separation of a gas-bubble differs materially from that of a drop in this respect. In the case SLG it is the persistent cohesion of the liquid which gives the drop a spheroidal form, and thereby assists gravita- tion to overcome the stubborn cohesion of the liquid. In the case of SLL the separation is assisted by the persistent cohesion of the liquid medium, which also tends to mould the drop into a spherical form, and is hindered by the stubborn cohesion and weight of the medium, which, by resisting its descent, increases its weight. In the case of a bubble, the ascent of the bubble is due wholly to the descent of the liquid medium ; and the spheroidal form of the bubble is due wholly to the persistent cohe- sion of the liquid medium ; for this cohesion is most completely satisfied when the cavity containing the gas is most spherical. We may now examine seriatim the influences of the seven conditions noticed above. SGL. Influence of rate. — To examine the effect of variation in gt we may take common air as the gas, distilled water as the liquid medium, the tube H of glass having an opening h of any convenient unmeasured size ; and as we are not concerned with the absolute, but with the relative sizes of the bubbles, the vessel M may be of an indefinite size. Table a shows the effect of variation in gt alone. Column 1 shows the values of fft. Column 2 the sequence of the experiments. Column 3 the number of bubbles. Column 4 the mean relative size of a single bubble at the respective rates of column 1 . 26 Prof. Guthrie on Bubbles. TABLE a. From glass, air-bubbles through water. T=23°C. B = 767millims. [Jan. 19, 1. gt. 2. Sequence of experiment. 3. Number of bubbles haying together the Tolume M. 4. Relative mean volume of single bubble. 0-33 \l 96] 97^ 96-66 I 9 97 J f 4 100) 1 5 99 0-50 g 100 > 99-80 16 100 17 100 J 3 1041 10 103 1-00 11 19 103 I 103 f 103-00 2 103 14 102J 12 97] 13 98 2-00 15 18 98 I 98 f 99-17 20 103 2-1 101J 5-00 1 103 103-00 It would at first seem as though there were a well-marked difference depending upon the value of gt. But in this method of experimenting there is a possible maximum error of two bubbles in each case, or an error of four bubbles in the comparison of two instances. This nearly covers the observed discrepancy. To set this point at rest, experiments were made with a larger number of bubbles as follows. The vessel taken for M was a 100 cub. centims. flask. The water in A was each time filled up to a. Only those two of the values of gt which gave the most widely differing results in the preceding Table were reexamined, viz. gt= 0'33 and gt= 1 -00. A thread was fastened to the end of the siphon D, so as to deliver its con- tents in a series of very rapid and minute drops. 1865.] Prof. Guthrie on Bubbles. TABLE ft. From glass, air-bubbles through water. T=23°C. B=767millims. 27 gt. Number of bubbles in 100 cub. centims. Mean absolute volume of single bubble. 0-33 / 19701 1 1970 / cub. centim. 0-05076 1-00 J 1974 1 \1972J 0-05068 Hence, under these conditions, rate has little or no influence upon bubble- size. In order to see whether a tube of different calibre would give rise to bubbles more sensitive in regard to their rate, a narrower orifice at h was employed. The flask M had a capacity of 50 cub. centims. The following mean results were obtained, each mean being derived from two experiments : — . Number of bubbles in Absolute volume of 50 cub. centime. single bubble. /( cub. centim. 0-33 1927 0-02595 1-00 1945 0-02571 This result, taken together with Tables a and ft, shows how small is the effect of rate upon bubble-size. If anything, there is, on the whole, a very slight tendency to diminution in bubble-size asfft diminishes — that is, as the rate increases. This is just the reverse of what was found to be the case with SLG. Most probably, however, this effect is not due specifically to the rate, but to the alteration in the diameter of the orifice at different rates. When a rapidly succeeding series of bubbles passes through the orifice h, the sides of the delivery-tube are swept more completely dry than when the bubbles pass more slowly ; so that in the former case the opening is, in fact, a little larger than in the latter. We shall see in the sequel how sensitive bubble-size is to variation in the width of the delivery- tube. It may be here noticed that, unless the tube H remains strictly in the same position, it is hopeless to attempt to get uniformity in results. This is especially the case when the opening h is turned half up in the shape of a siphon ; for then the least displacement out of the vertical causes virtu- ally an alteration in the available size of the opening, and a consequent variation in bubble-size. A great and otherwise unaccountable variation in the bubble-number, under circumstances apparently identical, directed attention to this source of error. By taking a wider tube, and allowing the end to contract in the blowpipe flame, a rounded opening is produced, the horizontal projection of which is much less variable with alteration in the verticalness of the tube H. 28 Prof. Guthrie on Bubbles. [Jan. 19, The reason why bubbles are less sensitive to variations in gt than are drops is sufficiently obvious. In the case of SLG, variation in gt affects the size of a drop by varying the thickness of the liquid-film which covers the solid at the moment of the drop's separation. We have seen that when this film is thin, in consequence of slowness in the supply of liquid to the solid, the size of the drop is diminished, because the solid reclaims liquid from the drop-root at the instant of the latter' s departure. But in the case of a bubble, at least in the arrangement of the above experiments, there is in all cases an indefinitely great aeriform residue, the separation of the bubble being determined by the superior density of the liquid medium, and by its persistent cohesion. Rate being thus of no appreciable influence upon bubble-size, we are not compelled to take the same extreme precaution to ensure uniformity of gt, as was found necessary with drops. Effect of change in the chemical nature of the bubble-gas. — The gases examined were hydrogen, oxygen, nitrogen, carbonic acid, and atmospheric ah-. Boiled water was left for several hours in the bags containing the gases, so that the gases might be perfectly saturated with water, and the water with the gases, and so that they might have the same temperature. This water was then employed to fill the vessel A. By this means all disagreement between the volume of the bubbles and the volume of the water flowing from D, caused by the solution of the gas in the water of A, is avoided. In each case the gas was allowed to bubble through G until the water in it was saturated. The following Table shows the results obtained : — Column 1. The gas employed. Column 2. The number of bubbles having together the volume 50 cub. centims., each number being the mean of three experiments. Column 3. The absolute mean volume of a single bubble. TABLE y. M=50 cub. centims. T=24°C. B=766 millims. Bubble-gas. 2. Mean number of bubbles having the volume 50 cub. centims. 3. Absolute mean volume of single bubble. Nitrogen 2173-0 cub. centim. 0-023009 Air 2070-0 0-024154 Carbonic acid 2035-0 0 024570 Oxygen 2021-7 0'024731 Hydrogen 1981-3 0*025235 1865.] Prof. Guthrie on Bubbles. 29 The chemical nature of the gas, therefore, has also very little influence upon bubble-size. The two purely physical influences active in determin- ing the bubble-size are the density of the gas and its solubility in water. These act to produce opposite effects. Increase of density in the gas delays the departure of the bubble, and thereby increases its size ; increase in the solubility of the gas in water impairs the stubborn cohesion of the water, and thereby diminishes the bubble-size. If p and q be the specific gravities of two gases P and Q referred to water, the buoyancy of two equal bubbles of them will be respectively where W is the weight of an equal volume of water ; that is, W (q— p) is the difference in buoyancy of the two bubbles. The gases arranged in their order of density are C02, O, Air, N, H. Arranged in order of solubility (at 20° C.), CO2, O, H, Air, N. The properties density and solubility are of course incommensurable, so that we cannot predict the extent to which they may counteract one another in the same gas to determine its bubble-size. But the order of the gases in Table y is quite consistent with our previous knowledge. Thus the bubble- size of air is intermediate between the bubble- sizes of nitrogen and oxygen. It would, however, at present be premature to attempt to make use of bubble-size to furnish an additional equation in gas-analysis. Effect of temperature and of tension. — The first of these has also a twofold action, by changing the density of the gas, and by changing the cohesion of the liquid. Within a natural range of 10° C. change of tem- perature takes no appreciable effect upon bubble-size. Also a variation of three-quarters of an inch in the natural barometric mercurial column is without sensible influence. These two influences were not made matters of special study, but were only examined with the view of ensuring absence of error from other experiments. Effect of change in the geometrical distribution of solid : size of orifice. — The change examined in this sense was the alteration hi the size of the orifice through which the gas bubbled. For this purpose the ends of six tubes of various internal diameter were ground flat, and until they had exactly the same length. One end of each tube was stopped by a little glass disk covered with a film of wax. The tube was then filled to over- flowing with distilled water, and another little disk was pressed on the top, the superfluous water being wiped off. The tube was then weighed, emptied, and dried and reweighed. The same being done for each tube, the volumes of the tubes are known to be in the same proportion as the weights of their liquid contents, the diameters or radii of the tubes being in the ratio of the square roots of the same weights. To calibrate tubes in this manner, water is to be preferred to mercury, because the latter leaves a film of air between itself and the glass, and thereby introduces a considerable error in the deduced calibre of very narrow tubes. The tubes were inserted 30 Prof. Guthrie on Bubbles. [Jan. 19, into the cork of the tube G, fig. A. The vessel M was a burette graduated into tenths of cubic centimetres. A hundred bubbles at gt=2"-Q were allowed to pass through G, and the water from D was measured. TABLE S. Eelative area* of sections of tubes. Mean volume of 100 bubbles. Relative radii of tubes. Actual observed volumes of 100 bubbles. cub. centims. 0-0204 3-5 0-1428 3-5 3--S 0-2112 14-9 0-4595 14-9 14-9 0-3642 15-2 0-60348 15-1 15-3 1-9880 17-8 1-4099 17-9 17-7 3-1002 24-4 1-7607 24-3 24-5 4-4094 31-9 2-0998 31-9 31-9 From this Table we see that the bubble-size is very sensitive to the size of the orifice. The bubble-size is doubled if the radius of the orifice is increased fivefold ; and so on. The same effect can also be well shown in a manner quite analogous to that adopted * to show the effect of varia- tion in radius of curvature of the solid (SLG). If the same quantity of gas be made to bubble in succession through the same liquid, similarly disposed in similar vessels, and if the tubes through which it is delivered have continually decreasing diameters, then the rates of bubbling are seen to follow the inverse order of the diameters of the tubes. Fig. D shows such an arrangement, which requires no explana- tion. In fact the reason why increase in radius of curvature in the case SLG produces increase of drop-size is very similar to that which causes increase of orifice to increase bubble-size in the case SGL. In the former case the thickness and general approximation of the residual liquid- film to the drop is greatest in large and flat surfaces ; in the latter the area of residual gas is larger when the orifice is larger. When, around a large orifice, the liquid medium closes upon the bubble, the latter is not so straitened for material as when the orifice is narrow. The influence of the size of the tube upon bubble-size is of considerable practical importance. In washing a gas, in separating two gases from one another by a medium which absorbs one of them, in saturating a liquid by a gas (a process which so often occurs in manufactures and analysis), the completeness of the operation invariably depends upon the extent of surface in common between the gas and liquid during a given time. If a spherical bubble, having the volume V and the surface S, be V divided into two equal spherical bubbles, each having the volume -^ and the surface s, then S 1 On Drops, p. 460. 1865.] Prof. Guthrie on Bubbles. 31 So that if the surface of the original bubble be 1, the surface of the two bubbles of half the size taken together is 1-259885. By making the gas-delivery-tube small, the absorbent surface of the same quantity of gas which passes through is increased in this manner, and the absorption is consequently more rapid or more complete. Effect of change in the chemical nature of the liquid medium. — To examine this (perhaps the most interesting phase of the causes of variation in bubble-size), the gas-bag L was replaced by a chloride-of-calcium tube. The cotton-wool of J was saturated with the liquid, which was placed for examination in G ; so that the bubbling gas was dry air already saturated with the vapour of the liquid through which it had to bubble. It is clear that if the air so charged were to come into contact with the water in A, the vapour would dissolve in the water, while the air would become moist ; a difference in volume would be thereby occasioned, according to the dif- ference of tension of the vapour of the liquid in G and J and that of water. To avoid this source of error, the vessel A was filled with mercury. After each experiment the vessel A was completely refilled with mercury, so as to expel the vapour of the liquid employed in the previous experi- ment. The mercury was then run off at D, until it fell in A nearly to the mark a. The liquid under examination in G had a height above h in- versely as its specific gravity : this the graduation of the tube G made easy. By this means the pressure on the gas as it issued from h was the same in all the experiments. The vessels A, G, and J were all sunk in the same trough of water, so that the volume of the air should undergo no alteration from temperature, either during or after its passage through G. When gt had been brought exactly to 2", and the mercury in A had sunk to a, a graduated burette was brought under the end of the siphon D, and kept there while 100 bubbles passed through G. The numbers of column 2 are each of them the mean of two determinations. TABLE e. fft=2". T=25° C. B = 764 millims. Liquid medium. Mean absolute volume of 100 bubbles of air. Mercury. . . . cub. centims. 41-2 Glycerine 11€45 Water 8-60 Butyric acid .... Acetic acid Alcohol 5-82 572 4-80 Benzol 4-80 Turpentol Acetic ether .... 4-53 372 32 Prof. Guthrie on Bubbles. [Jan. 19, These liquids, which were purposely taken the same as those whose drop- sizes were examined, are arranged in Table e in the order of the magnitude of the bubble-size. We see that the order is not the same in the two cases. The difference is due to the elimination in Table e of the influence of gravitation. In fact the only forces which influence bubble- size, as shown in Table e, are the retentive and stubborn cohesions of the liquid* ; for the first of these seeks to diminish, the second to increase the bubble-size. If RC be the retentive, and SC the stubborn cohesion, the liquids are arranged in Table e in the same order of magnitude as are the SP values of =— T. The density of a liquid seems therefore to vary with its IvC stubborn rather than with its retentive cohesion ; for there is an evident general tendency in the above Table e for the liquids to arrange themselves in the order of their specific gravities. Water once more distinguishes itself, taking a higher place in the scale than its density would point to : this must arise either from its exceptionally great stubborn, or from its ex- ceptionally small retentive cohesion. Acetic ether and alcohol are also exceptional — the former taking a lower, the latter a higher place in the scale than would be the case if the same state of quantity of matter in a given space (which is usually measured by means of gravity) affected also the cohesion of the liquid so as alone to determine the bubble-size of a gas passing through it. Perhaps also the gas having different degrees of solubility in the different liquids may affect their cohe- sions unequally. This source of variation, however, is probably very small, as we have seen to be the case when the gas varies and the liquid remains the same. A few experiments with a mixture of benzol and turpentol, and with alcohol and water, showed that in all cases the mixed liquid gives rise to a bubble intermediate in size between those caused by the single liquids. By measuring the volume of a greater number of bubbles, the actual dif- ferences of bubble-size due to various liquids would of course become more apparent. Throughout the examination of drops and bubbles in the present and previous communications, I have sought to direct attention to the main influ- ences which fix the size of a drop or bubble, rather than to pursue any one branch of the inquiry into its minute ramifications. Further, the subject has been treated wholly from a statical point of view ; that is, the bubble and drop have been considered at that period of their being when the con- tending forces which act upon them have brought them into a state of un- stable equilibrium or incipient motion. It is in fact only at this point, the instant of their ripeness, that they have a definite size ; for their size increases until the contending forces themselves withdraw the drop or bubble from the sphere of the action which determines their volume. Knowing now the direction and ^approximately the relative amounts of the effects due to the various conditions under which the drop and bubble * ^or the meaning of these terms see Paper "On Drops," p. 469. 1865.] On the Invisible Radiation of the Electric Li- or even yirVo^ °f the diameter, and often very steep. On the sun the same proportion would give cliffs 400 or 800 miles high, and with the spot in a position 60° from the centre of the sun, such cliffs would on one side conceal half or more of one side of the terrace (b), while the other side (b1) of the terrace remained entirely visible. If we suppose that a is not a steep cliff but a prolonged slope, so that even toward the edge of the sun the whole of the interior area may be seen, the limit of the difference of level between the general surface (*) and the interior terrace (b b') can be calculated. For example, In former observations of remarkable spots (1862), and again in 1863 * Outlines of Astronomy (Ed. 1833), pi 3. d. 52 Prof. Phillips— Physical Aspect of the Sun. [Jan. 26, and 1864, I have several times noticed this persistence of the elliptically contracted spot with its nucleus, equidistant from the borders, very near to the edge, both coming on and going off, certainly within 10° of the edge, from which it may be inferred that in that case the angle of inclination of the edge of the spot to the general surface could not be greater than 10°. Taking the case of 10°, and applying it to the spot now under considera- tion, the difference of level in miles between *, the general solar surface, and b, the ring terrace, might =a sin 10°=300 miles, but could not exceed it. This result is represented in the preceding diagram. Nor can the spot be sunk in a deep saucer-shaped concavity like for the same reasons. But, however deeply the spot may be sunk below the surface of the sun, no notch could appear in consequence of that at the limit of the sun ; for before reaching the limb the angle a E a', under which it is seen from the earth (E), would become invisibly small, and the space a— a' become invisible. Even if the sides a and a' were very unequal in level, the leading edge a' being depressed, this would make no visible notch on the limb of the sun, except the spot were enormously large, as well as very deep- — much greater for instance than 40,000 miles. Except in very rare cases, then, the sun's edge must always appear truly circular, notwithstanding the depressions of the spots and the elevations of the faculse. Finally, I remark that the spots may appear black, dark, grey, &c., not because they really are so dark as they seem, but that, being less luminous than other parts of the disk, they acquire this relative darkness under the operation of the optical apparatus, and the influence of contrast on the sensation. An extremely good way of viewing the spots is to project the sun's image on to a smooth porcelain screen, about a foot or 18 inches in diameter ; very smooth white paper answers very well. Thus tried, every imaginable degree of relative darkness appears in the spots, and the faculse come out bright and distinct. In this experiment, the spots seem so dark in the nuclei as to suggest the hypothesis that the parts of the sun to which they correspond really emit specially heat-rays, below the range of refrangibility which brings to our eyes light and the power of sight. Heat- rays and light-rays come to the earth together, but that is no reason for thinking they must spring in mixed pencils from every part of the sun equally. In my way of considering it, this rather confirms the idea of the deep black nuclei being the sun's body, the penumbrse that body partially seen through the atmosphere, and the facular region transmitting to us rays which have acquired a higher refrangibility than that with which they started, by a peculiar change in the sun's atmosphere, which may justly be called his photosphere. SH vt / t* . ^ f -i 3 k 1865.] Prof. Plucker on a New Geometry of Space. 53 February 2, 1865. Major-General SABINE, President, in the Chair. The following communications were read : — I. " On a New Geometry of Space." By JULIUS PLUCKER, For. Memb. E.S. Received December 22, 1864. (Abstract.) Infinite space may be considered either as consisting of points or trans- versed by planes. The points, in the first conception, are determined by their coordinates, by x, y, z for instance, taken in the ordinary significa- tion ; the planes, in the second conception, are determined in an analogous way by their coordinates, introduced by myself into analytical geometry, by t> u> v f°r instance. The equation represents, in regarding x, y, z as variable, t, u, v as constant, a plane by means of its points. The three constants t, u, v are the coordinates of this plane. The same equation, in regarding t, u, v as variable, x, y, z as constant, represents a point by means of planes passing through it. The three constants x, y, z are the coordinates of this point. The geometrical constitution of space, referred hitherto either to points or to planes, may as well be referred to right lines. According to the double definition of such lines, there occurs to us a double construction of space. In the first construction we imagine infinite space to be traversed by lines, themselves consisting of points ; an infinite number of such lines in all directions pass through any given point ; the point may describe each of the lines. This constitution of space is admitted when, in optics, we regard luminous points sending out in all directions rays of light, or, in mechanics, forces acting on points in any direction. In the second con- struction, infinite space is regarded likewise as traversed by right lines, but these lines are determined by planes passing through them. Every plane contains an infinite number of lines having within it every position and direction, round each of which the plane may turn. We refer to this second construction when, in optics, we regard, instead of rays, the corre- sponding fronts of waves and their consecutive intersections, or when, in mechanics, according to Poinsot's ingenious philosophical views, we intro- duce into its fundamental principles " couples," as well entitled to occupy their place as ordinary forces. The instantaneous axes of rotation are right lines of the second description. The position of a right line depends upon four constants, which may be determined in a different way. I adopted for this purpose the ordinary system of three axes of coordinates. A line of the first description, which VOL. XIV. F 54 Prof. Pliicker on a New Geometry of Space. [Feb. 2, we shall distinguish by the name of ray, may be determined by means of two projections, for instance by those within XZ and YZ, represented by x = rz + P> or by In admitting the first system of equations, a ray is determined in a linear way by means of the four constants r, s, p, a, which may be called its four coordinates, two of them, r and *, indicating its direction, the remaining two, after its direction being determined, its position in space. In adopting the second pair of equations, t, u, vxt vy will be the coordinates of the ray. A right line of the second description, which we shall distinguish by the name of axis, is determined by any two of its points. It is the common intersection of all planes passing through both points. We may select the intersection of the axis with the two planes, XZ and YZ, as two such points, and represent them by net +ztv= I, yu+zuv=l, or by In making use of the first pair of equations, the four constants x, y, zt) zu, indicating the position of the two points within XZ and YZ, are the coordi- nates of the axis. In adopting the second pair, the four coordinates of the axis are p, q, IT, K. A complex of rays or axes is represented by means of a single equation between their four coordinates ; a congruency, containing all congruent lines of two complexes, by means of two such equations ; a configuration, containing the right lines common to three complexes, by three equations. In a complex every point is the vertex of a cone, every plane contains an enveloped curve. In a congruency there is a certain number of right lines passing as well through a given point as confined within a given plane. A configuration is generated by a moving right line. In a linear complex the right lines passing through a given point con- stitute a plane ; all right lines within a given plane pass through a fixed point. Two linear complexes intersect each other along a linear con- gruency. In such a linear congruency there is a single right line passing as well through a given point as confined within a given plane. Three linear complexes meet along a linear confguration. Instances of linear complexes are obtained by means of linear equations between the four coordinates of any one of the four systems. A linear configuration of rays represented by three such equations between r, s, p, a is a paraboloid, immediately obtained ; between t, u, vx, vy a hyperboloid. 1865.] Prof. PI ticker on a New Geometry of Space. 55 A linear configuration of axes represented by three linear equations between p, q, IT, K is a hyperboloid, immediately obtained ; between x, y, zt, gu a paraboloid. Instances of linear congruences are exhibited by means of two linear equations, as well between t, u, vx, vy as between x, y, zt, ZM and their right lines easily constructed. The general linear equation, however, between any four coordinates does not represent a linear complex of the most general description. Besides, there is a want of symmetry, the four coordinates depending upon the choice of both planes, XZ and YZ. This double inconvenience, if not elimi- nated, would render it impossible to adapt in a proper way analysis to the new geometrical conception of space. But it may be eliminated in the most satisfactory way. For that purpose I introduced (in confining myself to the case of the co- ordinates r, s, p, a) a fifth coordinate (sp—ra), which is a function of the four primitive ones. Then the linear equation between the five coordinates is the most general of a linear complex. After having been rendered homogeneous by a sixth variable introduced, it becomes of a complete symmetry with regard to the three axes OX, OY, OZ. The introduction of the fifth coordinate (sp—rv) is the real basis of the new analytical geo- metry, the exploration of which is indicated in the ordinary way. In the paper presented, a complete analytical discussion of a linear complex is given. We may for any point of space construct the corre- sponding plane containing all traversing rays, and vice versa. Right lines of space associate themselves into couples of conjugated lines ; to each line a conjugated one corresponds. Any right line intersecting any two conjugated, is a ray of the complex. Each ray of it is to be regarded as two coincident conjugated lines. It is easily shown that each linear com- plex may be represented by means of any one of the following three equations, in which Jc indicates the same constant : sp — ra = k, obtained each month from deflection ob- servations at the two distances 1-0 and 1*3 foot, has been adopted for de- ducing the measure of horizontal force. Observations taken to determine the position of the zero-point on the scale of the declination magnet, gave the same result as was obtained in 1859. The discrepancies in the Declination observations . may possibly be in a considerable degree occasioned by diurnal variation, as the observations varied in regard to the hour of the day ; in future this will be avoided by making the observations always at a fixed hour. The discrepancies may also have been in part occasioned by magnetic disturbance which we have no present means of eliminating. OBSERVATORY. Greenwich Oh 9m 52s- 68. Height above Sea-level 381 feet. Magnetic Observations for 1864. Declination. Magnetic Dip. Absolute Measures. Values of 1 w.s Stonyhnrst. Mean Time. West Declina- nation. Day and Hour. 1 £ Dip. X,or Hori- zontal Force. Y, or Vertical Force. 9 46 32 69 48 47 69 49 42 69 44 10 3-5877 9-7455 10-3849 3-5950 9-7582 10-3990 3-5995 3-5999 3-6055 9-7715 9-7951 9-7659 10-4134 10-4356 10-4102 18th... 4 15p.m. ,, 6 Op.m. 22 15 0 21 57 30 6th... 7 Op.m. 22 1 40 5th... 3 Op.m. 3 30 p.m. 1 2 69 44 40 69 43 10 3-5975 9-7420 10-3849 19th... 5 39p.m. 20th... 5 35p.m. 21 59 35 22 6 10 12th... 9 30a.m. 27th... 9 0a.m. 1 1 69 47 21 69 46 40 3-5927 9-7560 10-3963 10th... 9 50a.m. 15th... 9 0a.m. 22 23 40 22 23 40 6th... 9 30a.m. „ 10 0a.m. 1 2 69 46 47 69 42 44 3-5942 9-7402 10-3829 10th... 9 0a.m. 9 2a.m. 22 38 55 22 36 40 9th... 8 30a.m. 930am. 1 2 69 46 0 69 45 36 3-6004 9-7665 10-4090 16th... 9 0a.m. 2238 0 loth... 9 0a.m. 1 69 46 23 3-5963 9-7600 10-4014 Means for 1864 1 69 46 34 ' 3-5967 9-7616 1 10-4031 1 68 Rev. W. Sidgreaves — Magnetical Observations. [Feb. 9, Note by the President. Mr. Sidgreaves's observations, combined with those made at the same spot in 1858 in the course of the second magnetic survey of England, supply the materials for a first approximate deduction of the present amount of the secular change of magnetic dip and of the total magnetic Force at Stony- hurst. Commencing with the Dip : — the results in 1858 were as follows (Brit. Assoc. Reports, 1861, pp. 253 & 254) :— Sept. 20. Kew Circle No. 30. Needle 1 .... 70 012 Rev. W. Kay. Nov. 2. Kew Circle No. 32. Needle 1 .... 69 57 44 Rev. A. Weld. „ 14. „ „ .... 70 3 30 „ 14. „ „ ....70 4 21 Mean : corresponding in date to 1858.8 70 1 27 And by the present Observations, correspond- ing in date to 1864.5 69 46 34 Difference, corresponding to 5.7 years .... 14 53 whence we have an annual secular decrease of 2'-614 ; mean epoch 1861.9. In a memoir presented to the Royal Society in 1861, " On the Secular Change of the Dip in London between 1821 and 1860," printed in vol. xi. of the 'Proceedings,' pp. 144-162, the mean annual secular decrease of the dip in the years from 1821.65 to 1859.5 is stated to have been 2'-69, mean epoch 1840.6 ; and in the 21.2 years between 1838.3 and 1859.5, 2-63 ; mean epoch 1848.9. Proceeding to the Total Force : — its value obtained by myself at Stony- hurst by experiments of deflection and vibration with the Survey Collimator No. 5, in October 1858 was 10'385 in British units (Brit. Assoc. Reports, 1861, pp. 264, 268) ; and by the experiments of Mr. Sidgreaves with the apparatus belonging to Stonyhurst College (originally obtained from Kew), its mean value in 1864, derived from the twelve monthly determinations, was 10'4031 ; the difference is '0181 in 5.75 years, or an annual increase of 0031. To compare with this, we have the statement in the British Survey (Brit. Assoc. Reports, 1861, p. 273), that from the absolute measures made monthly at Kew between April 1857 and March 1862 the total force had increased at Kew during that interval at an average annual rate of •0025. In the same memoir it was also inferred, from a general comparison of the isodynamic lines in the first and second British Surveys, that along a line drawn in a N.W. and S.E. direction the secular change would be found contemporaneously somewhat greater at a northern or north-western station than at a southern or south-eastern station — greater therefore at Stonyhurst than at Kew. The general fact that the value of the total force in Britain is progressively increasing, may be inferred alike by the observations at Kew and at Stonyhurst ; the precise amount of the annual increase at either station will require a longer continuance of the same careful and systematic observations as those at Kew and Stonyhurst. 1865.] Marcet — On the Peritoneal Fluid of Nematode Entozoa. 69 II. " Chemical Examination of the Fluid from the Peritoneal Cavity of the Nematode Entozoa." By Dr. W. MARCET, F.R.S. Re- ceived January 21, 1865. Some time ago Dr. Cobbold sent me a quantity of fluid which he had ex- tracted from about seventy perfectly fresh specimens of the Ascaris mega- locephala of the horse, and he requested me to make an analysis of it. I most willingly availed myself of this unusual opportunity of ascertaining the composition of this fluid, the sample procured by Dr. Cobbold being fortunately large enough for the purpose. The analysis of this fluid is interesting as showing that its composition is similar to Oiat of juice of flesh in the higher animals, and consequently that the process of assimilation occurs in these worms much in the same way as in those animals where the organs of digestion and circulation are perfectly developed. It also shows that a fluid similar to that existing in muscular tissue is apparently elaborated by the intestines of the Ascarides, while in the higher animals this fluid is formed from the blood. The fluid was turbid, of a pale yellow colour, and emitted an offensive odour, although not of decomposition. Microscopical Examination . Principally fine granular matter ; a few elongated bodies, some con- voluted, as if consisting of this granular matter cast by passage through a membranous tube. Some, but very few, spiral vegetable fibres and scales. Chemical Examination. Specific gravity 1*029, reaction slightly acid. 5 cubic centimetres were evaporated to dry ness, which yielded, in 1000 parts, Solid residue 827 Water .. . 917'3 The fluid, when nearly boiling, coagulated into a solid mass, it therefore contained a large quantity of albumen. With the object of separating the colloid from the crystalloid consti- tuents, I measured off 10 cub. centims. of the liquid and dialyzed it for twenty-four hours in a 6-inch dialyzer. By this operation the fluid lost its acid reaction, becoming neutral ; it has also parted with its smell. The Colloid Fluid. — The solution remaining on the dialyzer consisted principally of albumen ; it was evaporated to dryness, and the weight of the residue determined; this amounted to 0'532 grm., being 53 per 1000 of the fluid analyzed. The total solid constituents of the fluid being 82- 7 per 1000, it will be seen at once that about frds of the total residue con- sisted of colloid substances, and |rd of crystalloid. These numbers should be accepted as approximate results, there being no substance possessed of VOL. XIV. G 70 Marcet— On the Peritoneal Fluid of Nematode Entozoa. [Feb. 9, absolutely colloid or crystalloid properties, and a small proportion of colloid having probably found its way tbrough the membrane. The dry colloid residue was incinerated, and found to contain 1 -9 per cent, of ashes, which is so small a proportion as to show that very nearly the whole of the inorganic constituents of the fluid had passed through th3 membrane of the dialyzer. The Crystalloid Fluid. — This consisted of the solution in distilled water of those constituents of the ascaris-fluid which had found their way through the diaphragm of the dialyzer. It contained no albumen but some organic matters, and very nearly the whole of the inorganic salts of the original fluid. Evaporated nearly to dryness, a mass of crystals appeared after a lapse of time in the thick residue. Apart of the residue being ignited left a large proportion of ash, which was found to consist neafly entirely of phosphoric acid and potash. The aqueous solution of the ash reacted strongly alkaline, and emitted no carbonic acid when tested with a mineral acid, showing that there existed more phosphoric acid than was necessary to combine with the whole of the bases present. The absence of sulphates, of more than traces of chlorides, and of lime was very remarkable ; there might have been some soda present, but potash greatly predominated. There is no record in my note-book as to the presence or absence of mag- nesia. I now submitted to examination a solution in distilled water of the crys- talloid residue. It reacted acid ; the addition of a solution of nitrate of silver gave an abundant white precipitate with a slight yellow tinge, the fluid being acid before and after precipitation. There was therefore but a small proportion of common tribasic phosphate of potash present, and there appeared to be a much larger proportion of the bibasic phosphate ; the for- mer giving a yellow, and the latter a white precipitate with nitrate of silver. I finally determined the fatty matters present in a given weight of the original fluid, and found that 1000 parts of the ascaris-fluid contained 5'1 parts of fat. Conclusions. We may conclude from this inquiry that nutrition in the nematode worms can be carried on by means of a fluid containing few other substances besides albumen and phosphate of potash. If we now consider that the principal constituent of juice of flesh is phosphate of potash, both tribasic and bibasic, that the ascaris- and flesh-fluid are both acid, that in both fluids there is a very small quantity of chlorides with but very little or no soda and little or no lime, we shall be able to draw a very interesting par- allel between the assimilation in the highest and lowest animals. 1865.] On the Cerebral Commissures of the Marsupialia, §c. 71 III. " On the Commissures of the Cerebral Hemispheres of the Marsupialia and Monotremata, as compared with those of the Placental Mammals." By W. H, FLOWER, F.R.S. Received January 24, 1865. (Abstract.) As it is most convenient to pass from the best to the least known, and especially as the terms used in describing the anatomy of the vertebrated animals have iu most cases been originally bestowed upon parts of the human body, the Paper commences by a short description of the septum ventriculorum and commissures of the human brain. This is done with a view to establish clearly, both by their structure and development, the mutual relations of the great transverse commissure or corpus callosum and the fornix. The latter is denned as essentially a longitudinal com- missure, consisting of two lateral halves closely applied for a short space in the middle line, but each half belonging to its own hemisphere, and formed out of the longitudinal fibres bordering the superior margin of the ventricular aperture. There are no transverse fibres in the fornix proper, the so-called " psalterial fibres" connecting together the two hippocampi majores being a portion of the same system of fibres as the corpus callosum. The relations of these parts are shown in a series of longitudinal and vertical sections of the brains of the Sheep, Rabbit, Two-toed Sloth, and Hedgehog among Placental Mammals, and in the same way in the Kan- garoo, Wombat, and Thylacine among Marsupials, and the Echidna among Monotremes. After reference to the literature of the subject, more especially to the writings of Professor Owen, whose statement (Phil. Trans. 1837) of the absence in the marsupials of the "corpus callosum," or "great transverse commissure which unites the supra-ventricular masses of the hemispheres," in all placentally developed mammals * has been almost universally adopted, the author proceeds to sum up the result of the present investi- gation as follows. At the outset a confirmation is afforded of the important fact, first observed by Professor Owen, that the brains of animals of the orders Marsupialia and Monotremata present certain special and peculiar cha- racters, by which they may be at once distinguished from those of other mammals. The appearance of either a transverse or longitudinal section would leave no doubt whatever as to which group the brain belonged. In * In the paper by the same author " On the Characters, Principles of Division, and Primary Groups of the Class Mammalia " (Proc. Linn. Soc. 1858), the Subclass Lyencephala ("loose" or "disconnected" brain), equivalent to the Marsupialia and Monotremata, are characterized as having " the cerebral hemispheres but feebly and partially connected together by the ' fornix ' and ' anterior commissure,' while hi the rest of the class a part called ' corpus callosum ' is added, which completes the connect- ing or commissural apparatus." G2 72 . Flower — On the Cerebral Commissures [Feb. 9, the differentiating characters to be enumerated, some members of the higher section present an approximation to the lower; but, as far as is known at present, there is still a wide interval between them without any connecting link. The differences are manifold, but all have a certain relation to, and even a partial dependence on, each other. They may be enumerated under the following heads : — 1. The peculiar arrangement of the folding of the inner wall of the cerebral hemisphere. A deep fissure, with corresponding projection within, is continued forwards from the hippocampal fissure, almost the whole length of the inner wall. 2. The altered relation (consequent upon this disposition of the inner wall) and the very small development of the upper transverse commissural fibres (corpus callosum). 3. The immense increase in amount, and probably in function, of the inferior set of transverse commissural fibres (anterior commissure). Each of these propositions must now be considered a little more closely. Arguing from our knowledge of the development of the brain in placental mammals (for of that of the marsupials we have at present no information), it may be supposed that the first-named is also first in order of time in the gradual evolution of the cerebral structures. Before any trace of the budding out of the fibres which shoot across the chasm separating the hollow sac-like hemispheres, before the differentiation of a portion of the septal area into the anterior commissure, that remarkable folding of the inner wall, indicated by the deep (hippocampal) furrow on the surface and the corresponding rounded projection iu the interior, has already be- come distinctly manifest. Now the first rudiment of the upper transverse commissure is found undoubtedly at the spot, afterwards situated near its middle, to which in the lowest placental mammals it is almost entirely confined. This spot is situated a little way above and in front of the anterior end of the ventricular aperture, at the upper edge of the region of adherence of the two hemi- spheres (the future septal area). In the placental mammals this part is in direct relation to the great mass of the internal medullary substance of the hemispheres, which has to be brought into communication. In the marsu- pials, on the other hand, the prolonged internal convolution or hippo- campus spreading up to and beyond this point, forms the inner wall of the hemisphere from which the fibres pass across, and it is necessarily through the medium of this convolution, and following the circuitous course of its relief in the ventricle, that the upper part of the hemisphere can alone be brought into connexion with its fellow. Can this transverse commissure, of which the relation is so disturbed by the disposition of the inner wall of the hemisphere, be regarded as homo- logous to the entire " corpus callosum " of the placental mammals ? or is it, as has been suggested, to be looked upon as only representing the 1865.] of the Marsiqnalia, $c. 73 psaltcrial fibres or transverse commissure of the hippocampi ? Undoubtedly a large proportion of its fibres do come under the latter category. But even if they should nominally be all so included, it is important to bear in mind that we have still a disposition in the marsupial brain very different from that which would remain in the brain of any placental mammal after the upper and main part of the corpus callosum had been cut away. In the latter case the commissure of a very small part of the inner wall of the hemisphere alone is left, that part folded into the hippocampus. In the former there is a commissure, feeble it may be, but radiating over the whole of the inner wall, from its most anterior to its posterior limits. Granted that only the psalterial fibres are represented in the upper com- missure of the marsupial brain, why should the name of " corpus callosum " be refused to it ? These fibres are part of the great system of transverse fibres bringing the two hemispheres into connexion with each other ; they are inseparably mingled at the points of contact with the fibres of the main body of the corpus callosum, and are only distinguished from it in consequence of the peculiar form of the special portions of the hemisphere they unite. Indeed they are scarcely more distinct than is the part called " rostrum " in front. And although, like the fibres of the hinder end of the corpus callosum, they blend at each extremity with the fibres of the diverging posterior crnra of the fornix, they certainly cannot be con- founded with that body, which, as shown before, is essentially a longi- tudinal commissure. But is not the main part of the " corpus callosum" of the placental mam- mals also represented by the upper and anterior part of the transverse band which passes between the hemispheres of the marsupial brain and radiates out in a delicate lamina above the anterior part of the lateral ventricle ? The most important and indeed crucial test in determining this question, is its position in regard to the septum ventriculorum, and especially the pre- commissural fibres of the fornix. Without any doubt in all marsupial and monotreme animals examined (sufficient to enable us to affirm without much hesitation that the character is universal) it lies above them, as dis- tinctly seen in the transverse sections. This is precisely the same relation- ship which obtains in Man and all other mammalia, and this is one of the chief points in which not only the interpretation of facts but the observation of them recorded in the present paper differs from that of Professor Owen. The defective proportions of the part representing the great transverse commissure of the placental mammals, which appear to result from or to be related to the peculiar conformation of the wall of the hemisphere, must not lead to the inference that the great medullary masses of the two halves of the cerebrum are by any means " disconnected." The want of the upper fibres is compensated for in a remarkable manner by the immense size of the anterior commissure, the fibres of which are seen radiating into all parts of the interior of the hemisphere. There can be little doubt that the development of this commissure is, in a certain measure, comple- 74 Williamson — On the Atomicity of Aluminium. [Feb. 9, mentary to that of the corpus callosum. This is, moreover, a special characteristic of the lowest group of the mammalia, most remarkable because it is entirely lost in the next step of descent in the vertebrated classes. After a description of the brain of a bird, the conclusion is arrived at that, great as is the difference between the placental and implacental mammal in the nature and extent of the connexion between the two lateral hemispheres of the cerebrum, it is not to be compared with that which obtains between the latter and the oviparous vertebrate. IV. "Note on tie Atomicity of Aluminium." By Professor A. \Y. WILLIAMSON, F.R.S., President of the Chemical Society. Re- ceived February 6, 1865. In the " Preliminary Note on some Aluminium Compounds," by Messrs. Buckton and Odling, published in the last Number of the Society's ' Pro- ceedings,' some questions of considerable theoretical importance are raised in connexion with the anomalous vapour-densities of aluminium ethyle and aluminium methyle. The authors have discovered that the vapour of aluminium methide (Al2 Me6) occupies rather more than two volumes (H=«l vol.) at 163°, when examined by Gay-Lussac's process, under less than atmospheric pressure. The boiling-point of the compound under atmo- spheric pressure is given at 130°, and the compound accordingly boiled a good deal below 130° at the reduced pressure at which the determination was made. The vapour was therefore considerably superheated when found to occupy a little more than two volumes. When still further superheated up to 220° to 240°, it was found to possess a density equivalent to rather less than four volumes at the normal temperature and pressure. The aluminium ethyle was found to have a density decidedly in excess of the formula Al2 Et6 = 4 vols., but far too small for Al3 Me6 = 2 vols. From their analogy to aluminic chloride, Al2 C1G = 2 vols., the methide and ethide might be expected to have vapour-volumes corresponding to AP Me8 =2 vols., AP Et6 = 2 vols. The authors seem, however, more inclined to doubt the truth of the general principles which lead us to consider these hexatomic formulae the correct ones, than to doubt their own interpretation of the observations already made upon the new compounds. Even if the vapour-volume of aluminic chloride had been unknown to us, there were ample grounds for assigning to aluminium methide a molecular formula AP Me6, and a vapour-density corresponding to AP Me6 = 2 vols. ; for the close analogy of aluminic and ferric salts is perfectly notorious, and the constitution Fe2 O3 for ferric oxide settles AP O3 as the formula for alu- mina. With regard, however, to the chlorides of these metals, it might be supposed that the formula Fe CP and Al CP would be the most probable molecular formulae ; and Dr. Odling, in his useful Tables of Formulae, pub- lished in 1864, expressed an opinion in favour of these formulae by classing 1865.] Williamson — On the Atomicity of Aluminium. 75 as anomalous Deville's vapour-densities, which correspond to the higher formulae APCl°,Fe2Cr5. It is well known that Laurent and Gerhardt, whose penetrating minds raised so many vital questions of chemical philo- sophy, laid down a preliminary rule that every molecule must contain an even sum of the atoms of chlorine, hydrogen, nitrogen, and metals. Accord- ing to this rule, the formulae AP Cla and Fe2 Cl° would have no greater pro- bability than the formulae Fed3, A1C13; and judging by that rule, Dr. Odling naturally preferred the simpler formulae. Since Gerhardt's time chemists have, however, extended to the greater number of metals the arguments which proved oxygen to be biatomic ; and we now know that the alkali-metals, the nitrogen series, silver, gold, and boron, may count with the atoms of chlorine, hydrogen, &c. to make up an even number in each molecule, but that the greater number of metals must not be so counted ; for that in each molecule in which they are con- tained the sum of the atoms of chlorine, hydrogen, nitrogen, potassium, &c. must be even, just as much as if the atom of the diatomic or tetratomic metal were not in the compound. In a paper " On the Classification of the Elements in relation to their Atomicities," I had occasion to point out that inasmuch as iron and aluminium belong, partly by their own properties, partly by their analogies, to the class of metals which do not join with chlorine, &c. in making up an even number of atoms, the number of those other atoms in each molecule must be even in itself, just as if iron or alumi- nium were not there ; and that accordingly the formulae Fe2 Cl8, Al2 01° are really quite normal. In like manner I showed that the vapour-density of calomel, HgCl = 2 vols., is anomalous, as containing in a molecular volume a single atom of chlorine, although, in accordance with Gerhardt's rule, Dr. Odling had classed it as normal. I certainly understood that rny able friend accepted my suggestion in this case at least, for he speedily brought forward theoretical and experimental facts in confirmation of it. These examples serve to show that it was to be expected that the ethyle and methyle compounds of aluminium would contain an even number of atoms of ethyle and methyle in each molecule, and that their formulae would accordingly be Al2 Me8, AP Et6. It remains for us to consider how the deviation from our theoretical anti- cipations in the case of aluminium ethyle and the partial deviation in the case of aluminium methyle ought to be treated. Fortunately we have the benefit of some experience to guide us in this matter, for a considerable number of other compounds have been found to occupy in the state of vapour nearly double the volume which corresponds to one molecule ; but, with very few exceptions, all of them have already been proved to have undergone decomposition, so as to con- sist of two uncombined molecules. Thus sal-ammoniac is admitted to have the molecular formula NH4 Cl ; yet in the state of vapour this quantity occupies the volume of nearly two molecules, viz. four volumes. Has the anomaly led us to doubt the atomic weight of chlorine, nitrogen, or hy- 76 Williamson — On (he Atomicity of Aluminium. [Feb. 9, drogen, or to doubt any other of the results of our comparison of their compounds ? or has it led chemists to diffusion experiments with its vapour, proving it to contain uncombined HC1 and NH3, each occupying its own natural volume ? Has it not been proved that at the temperature at which sal-ammoniac vapour was measured, its constituents mix either without evolving heat (that invariable function of chemical action), or, according to another experimentalist, with evolution of far less heat than of the whole quantity of hydrochloric acid and ammonia combined, on coming together at that high temperature ? Again, SO1 H2 is known to represent the formula of one molecule of hydric sulphate, yet the vapour formed from it occupies nearly the bulk of two molecules. Has this fact cast any doubt on the atomic weights of the elements S, O, or H ? Or has it led to the discovery of peculiarities in the constitution of the vapour which would probably have escaped notice had they not been anticipated by theory, peculiarities which go a long way towards bringing the apparent anomalies within the law ? Nitric peroxide, N2 O4, was considered, from our knowledge of other vo- latile compounds of nitrogen, to be anomalous in its vapour-volume being N2Ol=4 vols. ; and we have been shown by the experiment of Messrs. Playfair and Wanklyn, that the anomaly almost disappears when the com- pound is evaporated by the aid of a permanent gas at a temperature consi- derably below its boiling-point, as its theoretical molecule N2 O4 is then found to occupy the two volumes which every undecomposed molecule occupies. This explanation seems to me to be the more entitled to grave consideration on the part of the discoverers of the new aluminium com- pounds, from the fact that the evidence in favour of it has been admitted to be conclusive by Dr. Odling, who classes nitric peroxide by the formula N2 O4 = 2 vols. among compounds with normal vapour-densities, in virtue of the fact that at low temperatures it can be obtained with that density, though having half that density at higher temperatures. The arguments for admitting that the low vapour- densities of the alumi- nium compounds are anomalous are even stronger than those which are ad- mitted in the case of nitric peroxide ; for it did require very severe super- heating to get the aluminium compounds to near four volumes, whereas it required very ingenious devices to get nitric peroxide out of the four-volume state. Such guiding principles as we have acquired in chemistry are the noblest fruits of the accumulated labours of numberless patient experi- mentalists and thinkers ; and when any new or old fact appears to be at variance with those principles, we either add to our knowledge by discover- ing new facts which remove the apparent inconsistency, or we put the case by for a while and frankly say that we do not understand it. The decision of the atomic weight of aluminium has involved greater difficulty than was encountered in the case of most other metals, owing to the fact of our knowing only one oxide of the metal, and salts correspond- 1865.] On the Synthesis of Tribasic Acids. 77 ing to it ; but the analogies which connect aluminium with other metals are so close and so numerous, that there are probably few' metals of which the position in our classification is more satisfactorily settled. We may safely trust that the able investigators who are examining these interesting compounds will bring them more fully than now within the laws which regulate the combining proportions of their constituent elements*; for, as it now stands, the anomaly is far less than many others which have been satisfactorily explained by further investigations. Meanwhile aluminium is a metal singular for only appearing in that pseudo-triatomic character in which iron and chromium appear in their sesquisalts. February 16, 1865. Dr. W. A. MILLER, Treasurer and Vice-President, in the Chair. The following communications were read: — I. " On the Synthesis of Tribasic Acids." By MAXWELL SIMTSON, M.D., F.R.S. Received January 25, 1865. (Abstract.) In a former Number of the ' Proceedings ' * I gave a preliminary notice of a tribasic acid having the composition C12 H8 O12, formed by the action of potash on tercyanide of allyle. The process for the preparation of the acid given in that paper I have since succeeded in improving very consider- ably, so that I can now obtain it in quantity and with tolerable facility. An account of the improved process is contained in the general paper which accompanies this abstract. The paper also contains a description of the crystalline form of the acid, for which I am indebted to Professor Miller of Cambridge. M. Kekulef proposes to call this body carballylic acid. This name I cannot, however, accept without some modification, as recent researches £ have proved that it belongs by right to crotonic acid. I propose therefore, in order to avoid confusion, to call it ^rzcarballylic acid. Since the appearance of my preliminary paper, I have also prepared and analyzed several of the salts and ethers of this acid, of which the following is a short account. Tricarballylic Ether, CflAf(a"' \ O6. This ether is readily prepared by conducting a stream of dry hydrochloric acid gas into a solution of tricarballylic acid in absolute alcohol. The pro- duct obtained on evaporating the alcohol distils between 295° and 305° C. * Proceedings of the Royal Society, vol. xii. p. 236. t Lehrbuch der Organischen Chemie, vol. ii. p. 187. J Annalen der Chemie und Pharmacie, vol. cxxxi. p. 58. 78 On the Synthesis of Tribasic Acids. [Feb. 16, It is a colourless liquid, is slightly soluble in water, and has an acrid taste. Heated with solid potash it suffers decomposition, alcohol being formed and the acid regenerated. Tricarballylic Amylic Ether, 9f1?HA°?" 1 O6. WlO -"-11/3 J This body is formed when dry hydrochloric acid gas is passed into a mixture of one part by weight of tricarballylic acid and two parts of pure amylic alcohol maintained at the temperature of boiling water. The pro- duct may be partially purified by heating it in a retort till 200° C., and then dissolving it successively in alcohol and in ether. It is a thick oily liquid, is heavier than water, and has an acrid taste. Its boiling-point is beyond the range of the mercurial thermometer. Heated with solid potash, it is resolved into amylic alcohol and tricarballylic acid. C12H506'" Glyceri-tricarballylate of Baryta, C6 H7O4' Ba2 This salt was prepared by maintaining for several hours at the tempera- ture of 200° C. in a sealed tube a mixture of one part of tricarballylic acid and two parts of pure glycerine. The product was neutralized by a solu- tion of baryta, evaporated to dryness, and digested with absolute alcohol to remove the uncombined glycerine. A buff-coloured powder was thus ob- tained having, I have no doubt, the composition expressed by the above formula, although my analyses do not correspond very well with it. The acid combined with the baryta is bibasic, and is represented by the formula Soda-salts of Tricarballylic Acid. The soda-salts of this acid are very soluble in water and difficult to crys- tallize. Three salts may, I believe, be found, containing respectively one, two, and three equivalents of sodium. One equivalent of the acid I fpund required for complete neutralization exactly three equivalents of pure carbonate of soda. The composition of the salt with two equivalents of C12H506'"1 sodium which I obtained in crystals is probably Na2 >• O6 + 4HO. H J Tricarballylate of Lime, 12C3 G [ O0 + 4HO. When a solution of this acid is neutralized with lime-water and evaporated, a white amorphous powder separates, which is the salt in question. It is sparingly soluble in water, and freely soluble in dilute acids. Tricarballylate of Copper, 12 /v5 a / O6. ou3 j This salt falls in the form of a beautiful bluish-green powder when sul- 1865.] On the Acids of the Lactic Series. 79 phate of copper is added to a hot solution of tricarballylate of soda. It is insoluble iu water, but soluble in dilute acids. Tricarballylate of Lead, C'2 *J ^°«'" J O6. This salt precipitates when an excess of acetate of lead is added to a solu- tion of tricarballylate of soda. It is a white powder insoluble in water, but soluble in dilute nitric acid. The composition of the foregoing salts and ethers fully confirms the view I took of the basicity of this acid in my preliminary paper. It is, I believe, at present the sole representative of its class. It will not, however, I believe, long remain so, as the process by which it has been obtained will, I have no doubt, be found to be of general application. This acid bears the same relation to citric acid that succinic bears to malic acid : — C12 H8 O12, tricarballylic acid. Cb H6 O8, succinic acid. C12 H8 Ou, citric acid. C8 H6 O10, malic acid. That this relationship exists not only on paper, but also in the nature of the bodies themselves, is, I think, highly probable. In order to arrive at cer- tainty on this point, I have endeavoured, by the addition of two equivalents of oxygen, to transform tricarballylic into citric acid. My researches in this direction have not hitherto been attended with success. II. "Notes of Researches on the Acids of the Lactic Series. — No. III. Action of Zincethyl upon Ethylic Leucate." By E. FRANKLAND, F.R.S., and B. F. DUPPA, Esq. Received February 1, 1865. In describing the production of ethylic leucate or diethoxalate *, formed when zincethyl acts upon ethylic oxalate, we assumed the intermediate formation of zincoleucic ether, and explained the reaction by the following equation, in which zinc is regarded as a monatomic metal ; — f(C2H6)2 OC2H , C2H5_ I OZn' Zn' - OC;HS Ethylic oxalate. Ziucethyl. Zincoleucic ether. Zincethylate. In contact with water we conceived zincoleucic ether to be decomposed with the formation of ethylic leucate and zinc hydrate, f(C2H5)2 f(C2H5)2 p J OZn' , H 0 r J OH Zn'l n CU 0 +H20 = C2j Q +H JO. [OC2H5 ( OC2H5 Zincoleucic ether. Ethylic leucate. Since these reactions were thus expressed, zinc has come to be generally * Proceedings of the Royal Society, vol. xii. p. 396. 80 Frankland and Duppa— On the Acids [Feb. 16, regarded as a diatomic metal, a circumstance which has led us to study the action of zincethyl upon ethylic leucate, with a view to the more satisfactory elucidation of the above changes, which finally result in ethylic leucate. Assuming the diatomicity of zinc, which can now no longer be doubted, it is obvious that by the loss of one atom of ethyl, zincethyl will, like many other organo-metallic bodies, pass from a condition of perfect to one of partial saturation, in which it will play the part of a monatomic radical. That zincethyl, in being acted upon by oxygen, passes through two distinct stages of change has been already indicated by one of us in de- scribing the reactions of that body* ; for when a current of dry oxygen is made to pass through an ethereal solution of zincethyl, dense white fumes continue to fill the atmosphere of the vessel, until about one-half of the total quantity of oxygen necessary for the complete oxidation of the zinc- ethyl has been taken up. Then, the white fumes entirely cease, showing the absence of free zincethyl, and at the same moment the liquid, which up to that time had remained perfectly transparent, begins to deposit a copious white precipitate, which continues to increase until the remaining half of the oxygen is absorbed. If the process of oxidation be arrested when the white fumes cease to be formed, the product effervesces violently when mixed with water, owing to the escape of hydride of ethyl ; but when the oxidation is completed, the white solid mass produced consists chiefly of zincethylate, and does not in the slightest degree effervesce in contact with water. The two stages of this reaction depend essentially upon the succes- sive linking of the zinc with the two atoms of ethyl by means of diatomic oxygen. The first stage of oxidation is expressed by the following equa- tion:— C2 Hs , p. r, „ \ C2 H5 C2H5+ ~Zn \OCaH5- Zincethyl. Zincethylo-ethylate. The zincethylo-ethylate thus formed is perfectly soluble in ether, and is instantly decomposed by water according to the following equation : — „ „ fC2H5 2H 0_7 „ JOH C2H51 0 C2H5 1 \OC2H5 + 2U*U-Zn \OH+ H j° H Zincethylo-ethylate. Zinc hydrate. Alcohol. Ethylic hydride. Treated with dry oxygen, zincethylo-ethylate, in ethereal solution, absorbs a second atom of that element, and it is this further absorption that con- stitutes the second stage above referred to, resulting in the production of ethylate of zinc, 7n" / 0* ^5 4- f> — 7n» I O C2 H5 1 {OC2H3+ Zn 10C2H/ Wanklynf was the first clearly to point out the probable existence of zincmonethyl, or rather its homologue zinc-monomethyl, indicating at the * Phil. Trans. 1855, p. 268. f Journal of Chem. Soc. 1861, p. 127. 1865.] of the Lactic Series. 81 same time its radical functions, when he ascribed to the crystalline com- pound obtained in the preparation of zincmethyl the formula In the same memoir he also represented this compound as the analogue of mercuric methiodide, -rr „ f CH3 More recently Buttlerowf has prominently drawn attention to this beha- viour of organo-zinc compounds, and has succeeded in obtaining zincmethylo- methylate, 7n" / ^^3 IOCH3' in a condition approaching to purity, by passing a stream of dry air through a solution of zincmethyl in methyl iodide. M. Buttlerow's success in obtaining this body and his failure in converting it into zincmethylate, are both probably due to the comparative insolubility of zincmethylo-methy- late in methyl iodide, owing to which the first product of oxidation was, to a great extent, protected from the further action of oxygen. When, how- ever, ether is used as the solvent of zincethyl, the oxidized product remains in solution until the first stage is passed, after which zincethylate is gradu- ally precipitated until the second stage is completed. Indeed, as has been shown in the memoir above referred to (Phil. Trans. 1855, p. 268), the oxidation, instead of stopping at the first stage, proceeds even somewhat further than the second, and the product formed does not possess a com- position in any degree approaching that which M. Buttlerow asserts it to have. This is evident from the following numbers, and from the circum- stance that it does not effervesce in the slightest degree when mixed with water : — Percentage composition ._ according to Buttlerow's Percentage composition r H 7n T according to mean of formula Cffif } analyses. C.... .......... 34-53 25-43 H ............ 7'20 5-32 Zn ............ 4676 42-04 O ............ 11-51 27-21 100-00 100-00 The existence of monatomic organo-zinc radicals receives further support from the following experimental determinations, which also show the functions of such radicals in the formation of the ethers of the lactic series from ethylic oxalate. When zincethyl is added to leucic ether previously cooled in a freezing mixture, each drop of the zinc compound, as it comes into contact with the ether, hisses like anhydrous phosphoric acid when dropped into water. Torrents of hydride of ethyl are evolved, and the mixture finally solidifies to a white tenacious mass, which fuses on the application of heat, and does * Bulletin de la Soc. Chim. August 1864. 82 Frankland and Duppa— On the Acids [Feb. 16, not distil below 100° C., at about which temperature a violent action sets in ; a great quantity of gas is evolved, and the residue solidifies to a pitch- like mass, which, on treatment with water and subsequent distillation, yields about one-fourth of the leucic ether employed. If the above-mentioned white mass, instead of being heated, be mixed with water, it effervesces strongly, zinc hydrate is formed, and pure leucic ether separates in quan- tity nearly equal to that originally employed. In a quantitative experiment 12'93 grms. of zincethyl were treated with leucic ether, ex cess being avoided; 15'6 7 grms. of leucic ether were required to saturate the above quantity of zincethyl, and the weight of hydride of ethyl evolved, which was carefully determined, amounted to 3'08 grms. These numbers closely agree with those deduced from the following equa- tion : — "(C2H5)2 CjjJ-__+Zn,,{C:H:=c/ OC2H5 [ OC2H. Ethylic leucate. Zincmonethyl-ethylic leucate. as seen from the following comparison : — Theoretical. Experimental. Weight of hydride of ethyl evolved .. 3'04 „ 3-08 „ Zincmonethyl-ethylic leucate is a colourless viscous solid, soluble in ether, but apparently incapable of crystallization. It absorbs oxygen with avidity and in contact with water effervesces strongly, reproducing leucic ether according to the following equation : — 2H6)2 r(c2H5)2 ZnC2H OH C2H,j fOH + 2*i2U_U +Zn 02H5 OC2H5 Zincomethyl-ethylic Ethylic leucate. leucate. Zincmonethyl-ethylic leucate combines energetically with iodine ; an ethereal solution of the latter added, to it is almost instantaneously decolo- rized and a large quantity of iodide of ethyl is produced. In continuation of the above quantitative experiment the following results were obtained. The product of the action of 12'93 grms. of zincethyl upon 15*67 grms. of leucic ether decolorized an ethereal solution containing 23*75 grms. of iodine, the quantity required by the following equation being 25'04 grms., 5'4 4_c +Z.L+JC.H.I. Zincmonethyl-ethylic Zincoleucic ether. leucate. 1865.] of the Lactic Series. 83 It was obviously impossible to collect in a state of purity the iodide of ethyl thus set at liberty without considerable loss ; but the quantity of the pure iodide actually obtained was 12 grms. The abore equation requires 14-6 grms. On the removal of ether and iodide of ethyl, the mixture of zincoleucic ether and iodide of zinc forms a transparent gummy mass easily soluble in ether, bisulphide of carbon, and caoutchoucin, but totally incapable of crystallizing from any of its solutions. All our attempts to separate these bodies have hitherto proved abortive, and it is by no means improbable that they are chemically combined. The action of zincethyl upon ethylic leucate throws much light upon the production of the latter from zincethyl and ethylic oxalate, and scarcely leaves a doubt that, when zincethyl is added to ethylic leucate, there is reproduced the zinc compound from which the ethylic leucate was first formed. We may therefore express the two stages in the original produc- tion of ethylic leucate by the following equations : — L O C2 H. [ O Ca H. Zh.cethylo-ethylate. Ethylic oxalate. Zincmonethyl-ethylic leucate. (C2_H5)2 Zinc hydrate. Zincmonethyl-ethylic Ethylic leucate. leucate. III. " Notes of Researches on the Acids of the Lactic Series. — No. IV. Action of Zinc upon Oxalic Ether and the Iodides of Methyl and Ethyl mixed in atomic proportions." By E. FRANKLAND, F.R.S. and B. F. DUPPA, Esq. Received February 2, 1865. The reaction of zinc upon oxalic ether in the presence of iodide of amyl, the results of which we hope very shortly to have the honour of laying before the Royal Society, had led us to anticipate, that if an oxalate of one organic radical were treated with the iodide of another, one atom of di- atomic oxygen in the oxalic ether would be replaced by two different mon- atomic radicals. This anticipation was not, however, realized, as we have already shown*, when the reaction was extended to a mixture of iodide of ethyl with oxalate of methyl, and iodide of methyl with oxalate of ethyl. In both these cases the radicals presented in the form of iodides were the * Proceedings of the Royal Society, vol. xiv. p. 17. 84- Frankland and Duppa— On the Acids [Feb. 16, only ones entering into the composition of the resulting acids, which proved to have respectively the composition of leucic or diethoxalic acid, and dimethoxalic acid, Certain theoretical considerations, however, rendered it important for us to be able distinctly to label each radical entering into the composition of the derived acids, so as to enable us with certainty to trace its source, and, if possible, to determine its position or value in the resulting complex molecule. We therefore endeavoured to accomplish the desired end by acting with zinc upon a mixture consisting of one atom of oxalic ether and one atom each of the iodides of methyl and ethyl, by which we hoped to obtain an acid of the following composition : — rcui, CH3 cl ™ I OH Experiment completely proved the practicability of this reaction, and its result even exceeded our expectations, since not only was the ether corre- sponding to the above acid formed with the greatest facility, but it was produced almost to the complete exclusion of the ethers of leucic and dimethoxalic acids. 200 grms. of oxalic ether were mixed with the proper atomic propor- tions of iodide of methyl and iodide of ethyl, and were digested with granu- lated zinc for several days at a temperature of from 3o° to 40° C., until the supernatant liquid became oily, and solidified to a crystalline mass on cooling. Water being now added until effervescence ceased, the whole was submitted to distillation in an oil-bath. With the exception of a small quan- tity of the mixed iodides of ethyl and methyl that had escaped decompo- sition, the distillate consisted of a homogeneous liquid composed of water, ethylic and methylic alcohols, and an ethereal body, which last was sepa- rated by repeated agitation with large volumes of ether and subsequent rectification. In this manner there was obtained a large quantity of a liquid which boiled constantly at 1650>5 C., and yielded on analysis num- bers very closely corresponding with he formula 1865.] of the Lactic Series. 85 The production of this ether is explained in the following equations : — Oxalic ether. Zincmonethyl-etho- ethylate. methoxalate of ethyl. fcH35 nJ QZnCH3+2H,0=Ca< | ~6T~ I OT~ n J 1UJ1 [ OC2 H5 ^ OC2 H5 Zinc hydrate. Zincmonethyl-etho. Ethylic ethometh- methoxalate of ethyl. oxalate. A not inconsiderable amount of the ether thus formed in this and in the analogous reactions described in our previous communications, appears to be decomposed by the zinc hydrate ; at all events an appreciable quantity of the zinc-salt of the derived acid is always obtained from the residue left after distillation of the ethereal product. Ethylic ethomethoxalate, as we propose to 'name the new ether, is a colourless, transparent, and mobile liquid, possessing a penetrating ethereal odour much resembling that of ethylic diethoxalate. It is very soluble in water, alcohol, and ether, and has a specific gravity of '9768 at 13° C. It boils at 165°'5 C., and its vapour has a density of 4'98 ; the theoretical number for a two- volume vapour (H2O= 2 vols.) of the above formula being 5 '04. Ethylic ethomethoxalate is readily decomposed, even by aqueous solu- tions of the alkalies and of baryta, yielding alcohol and a salt of the base. The ethomethoxalate of barium was thus prepared. It crystallizes from an aqueous solution as a beautiful radiated mass of silky lustre, very easily soluble in water. Its analysis gave numbers closely corresponding with the formula >(CaH5)3 (CH3)2 (OH). 08 QBa" By exactly decomposing this salt with dilute sulphuric acid and evapo- rating the filtrate, first in a retort, and afterwards in vacuo, ethomethoxalic acid was obtained as a splendid white crystalline mass, fusing at 63° C., subliming readily at 100°, and condensing' in magnificent star-like groups upon a cold surface. It boils with decomposition at 190° C. Ethometh- oxalic acid is very readily soluble in ether, alcohol, and water ; small frag- ments of it thrown upon water rotate like camphor whilst dissolving. 86 Prof. Maskelyne— On New Cornish Minerals [Feb. 23, These solutions react powerfully acid, and readily decompose carbonates. The analysis of this acid gave numbers closely corresponding with the formula fC2 H5 CH3 H O OH We have prepared silver ethomethoxalate by treating the free acid dis- solved in water with carbonate of silver. This salt crystallizes in splendid mammillated masses half an inch in diameter, which are tolerably soluble in water. It gave numbers, on analysis, in accordance with the formula rC2H8 CH3 OH February 23, 1865. JOHN P. GASSIOT, Esq., Vice-President, in the Chair. The following communications were read : — I. "On New Cornish Minerals of the Brochantite Group." By Professor N. STORY MASKELYNE, M.A., Keeper of the Mineral Department, British Museum. Communicated by A. M. STORY MASKELYNE, M.A. Eeceived February 13, 1865. (Abstract.) On a small fragment of Killas from Cornwall, I discovered, several months ago, a new mineral in the form of minute but well-formed crystals. The specimen had come from Mr. Tailing, of Lostwithiel, a mineral- dealer, to whose activity and intelligence I am indebted for the materials that form the subject of this paper. After a little while he found the locality of the mineral, and sent me other and finer specimens ; but these specimens proved to contain other new minerals besides the one already mentioned. Two of these minerals are described in this paper, and a third will form the subject of a further communication. I. Langite. The first of these minerals which I proceed to describe is one to which I have given the name of Langite, in honour of my friend Dr. Viktor von Lang, now of Gratz, and lately my colleague in the British Museum. It occurs in minute crystals, or as a crystalline crust on the Killas, of a fine blue with a greenish hue in certain lights. The crystals are prismatic. The forms observed are (1 0 0), (0 0 1), (1 1 0), and (2 0 1) & (0 1 0), the 1865.] of the Brochantite Group. 87 normal inclinations giving the following angles, which are the averages of many measurements : — 1 I 0 1~10=56 16 10011 0=61 52 001 201 = 51 46 conducting to the parametral ratios a :£: c=l:0'5347:0-6346. The crystals are twinned after the manner of cerussite, the twin axis being normal to the plane (110). 1 1 0 (1 10) T 1 0=112 33 100 (110) 100=123 44 ! "10 (It 0) 110= 67 26 Cleavages seem to exist parallel to 0 0 1 and 1 0 0. The planes 0 0 1 and 1 0 0 are very brilliant. The plane of the optic axes, as seen through a section parallel to the plane 0 0 1, is parallel to 1 0 0. The normal to 0 0 1 would seem to be the first mean line, and it is negative. The optical orientation of the mineral is therefore 6, C, a. The crystals are dichroic. 1 . Seen along axis c, c, greenish blue. 6, blue. 2. Seen along axis a, c, darker greenish blue. 0, lighter bluish green. The specific gravity of Langite is 3€48 to 3-50. Its hardness is under 3. It will not abrade calcite. Before the blowpipe on charcoal it gives off water, and fumes and becomes reduced to metallic copper. Insoluble in water, it is readily dis- solved by acids and ammonia. Heated, it passes through (1) a bright green, and (2) various tints of olive-green, till (3) it becomes black. Water is given off the whole time, and finally it has a strongly acid reaction. The first stage corresponds to the loss of one equivalent of water ; the second reduces its composition to that of Brochantite ; at the third it loses all its water. The chemical composition of Langite is represented by the formula 3Cu" H'? Oa+Cu" S04+2H'2 0, which requires the following numbers :— Calculated Average percentage. found. 4 equivalents of copper 126'72=52-00 52-55 4 equivalents of oxygen 32' = 13-13 13'27 1 equivalent of sulphuric anhydride 40- =16-41 16'42 5 equivalents of water 45- = 18'46 18-317 24372 100-00 100-56 I have met with a small and old specimen of Connellite with a twin crystal of Langite associated with it. H 2 88 Prof. Maskelyne— On New Cornish Minerals. [Feb. 23, II. Waringtonite. To a Cornish mineral associated with Langite, emerald to verdigris-green in colour, occurring in incrustations generally crystalline, and seen occa- sionally in distinct individual crystals aggregated loosely on the Killas, I have given the name of Waringtonite, in honour of my friend Mr. Waring- ton Smyth. The crystals are always of the same form, that, namely, of a double-curved wedge. A narrow plane, 001, is very brilliant and without striation. It appears to be a cleavage-plane. A second, but scarcely measurable plane, 100, occurs at right angles to it, truncating the thin ends of the wedge. The prism planes in the zones 010, 001, and 010, 100 are uniformly curved. The planes of two prisms seem to exist in the zone 010, 001, but the angles, as approximately measured by the gonio- meter, are not very reliable ; one of them, however, may be pretty con- fidently asserted to be very near 28° 30', which is the mean of many measurements on four crystals. Seen in a microscope fitted with an excel- lent eyepiece goniometer, planes of polarization in the crystals are evi- dently parallel and perpendicular to the planes 100, 001; but whether a plane of polarization bisects the acute angle of the wedge, i. e. is parallel to 0 1 0 or to 1 0 0, or whether 1 0 0 is equally inclined to the planes forming the wedge — in short, whether the crystal is oblique or prismatic, it is very difficult to determine. The mineral frequently presents itself, moreover, in what appear to be twinned forms ; but the angles between the planes 1 0 0 in the two individuals are not sufficiently concordant, as measured on different crystals, to justify a speculation on the symbols of a twin face. Several analyses of Waringtonite concur in establishing its formula as 3Cu"H'202 + Cu" SO4+H'2O, as is seen by the following numbers : — 4 equivs copper .... . — 126-75 Percentage as calculated. j __ 53-99 Average found. 54-48 4 equivs. oxygen — 32- — 13-63 (calc. 13-756) 1 equiv. sulphuric anhydride 4 equivs. water = 40- = 36- = 17-04 = 15-34 16-73 14-64 234-72 =100-00 99-606 It also contains traces of lime, magnesia, and iron, and appears to be generally mixed with a small proportion of another mineral, which is pro- bably Brochantite, as Brochantite occurs in distinct crystals on some of the specimens of Waringtonite. Its specific gravity is 3'39 to 3'47. Its hardness is 3 to 3'5, being harder than calcite, and about equal in hardness to celestine. The entire difference of its crystallographic habit, the absence of the striation and marked prismatic forms so characteristic of Brochantite, its habitually paler colour,lower specific gravity (in BrochantiteG=3'87 to3'9), and hardness sufficiently distinguish it from that mineral. The moun- tain-green streak offers an available means of contrasting Waringtonite 1865.] Dr. Stenhouse— On Sulphobenzolates. 89 and Brochantite with Atacamite, the streak of which is of a characteristic apple-green. M. Pisani has published analyses of the two above-described minerals. In the former (possibly from having driven off part of the water in the preliminary desiccation of the mineral) he has found less water than I consider it really to contain, and he has consequently given to Langite the formula of Waringtonite. The green mineral which he has analyzed and described as Brochan- tite seems, from his analysis, to have contained a slight admixture of the ferruginous matrix, and also differs from mine in the estimate of the water. I confined my preliminary desiccation to a careful treatment of the bruised mineral with dried and warm blotting-paper, as many hydrated minerals of this class yield up part of their water when long exposed to a perfectly dry air, or to a temperature of 100° C. II. "Preliminary Notice on the Products of the Destructive Distilla- tion of the Sulphobenzolates." By JOHN STENHOUSE, LL.D., F.R.S., &c. Received February 15, 1865. The salt which I have hitherto chiefly employed is the sulphobenzolate of soda, C,2H5 Na 2SO3, which was prepared according to Mitscherlich's* directions, by precipitating crude sulphobenzolate of lime by carbonate of soda, separating the carbonate of lime produced, and evaporating the clear solution to dryness. The finely powdered salt, which had previously been thoroughly dried, was introduced into a small copper retort and subjected to destructive distillation, when a considerable quantity of carbonic acid was evolved, and a brownish-coloured oily liquid, covered by a layer of water, collected in the receiver. This oil was separated from the water and distilled in a retort furnished with a thermometer. The liquid began to boil at 80° C., and then rose slowly to 110° C., when only a small quantity of water, and an oil consisting chiefly of benzol, came over. The boiling-point then rapidly rose to 290° C., at which temperature the greater portion of the liquid distilled over, leaving a black residue in the retort. The oil boiling at 290° C. is of a pale yellow colour, heavier than water, and has an aromatic and slightly alliaceous odour. It contains a consi- derable amount of sulphur. "When this oil is brought in contact with nitric acid, a very violent action ensues with evolution of nitrous fumes, and when the resulting solution is poured into water, a crystalline mass of a pale yellow colour is obtained. This, when dried and washed with ether to separate a small quantity of adhering oil, is dissolved in hot spirit, from which, on cooling, two colour- less crystalline substances separate. The first of these, which constitutes the bulk of the product, forms beautiful rhombic plates, which, when crystallized out of benzol, may be * Fogg. Ann. vol. xxxi. pp. 283 & 634. 90 Stewart and Tait— Radiation from a Revolving Disk. [Feb. 23, obtained of considerable size and great lustre, closely resembling chlorate of potassa in appearance. This body also contains sulphur. The second substance, the quantity of which is comparatively small, crystallizes in long thin plates. The oil, when treated with concentrated sulphuric acid, dissolves with a fine purple colour, and from this solution water precipitates a crystalline body, an organic acid remaining in solution, which forms a crystalline lime-salt. I have likewise subjected to destructive distillation the sulphobenzolates of lime, ammonia, and copper. The two last yield very different products from the soda-salt. I am at present engaged in examining these as well as the other bodies mentioned in this Notice, and hope soon to be able to communicate to the Society the results of my investigations. III. " Preliminary Note on the Radiation from a Revolving Disk." By BALFOUR STEWART, M.A., F.R.S., and P. G. TAIT, M.A. Received February 23, 1865, The authors having been led by perfectly distinct trains of reasoning to identical views bearing on the dissipation of energy, have had preliminary experiments made on the increase of radiation from a wooden disk on account of its velocity of rotation, both in the open air and in vacua. These experiments were made with a very delicate thermo-electric pile and galvanometer. In the experiments in the open air the disk was of wood ; its diameter was 9 inches, and it was made to rotate with a velocity somewhat less than 100 revolutions in one second. A sensible effect was produced upon the indicating galvanometer when the disk was made to rotate, and this effect appeared to be due to radiation, and not to currents of air impinging against the pile. In amount it was found to be nearly the same as if the disk had increased in temperature 00> 75 Fahr. In the experiments in vacuo the diameter of the wooden disk was over 12 inches ; its velocity of rotation was about 100 revolutions in one second, and the pile was nearer it than when in air. Under these circumstances, with a vacuum of 06 in., an effect apparently due to radiant heat was ob- tained, amounting to nearly the same as if the disk had increased in tem- perature 1°'5 Fahr. Bearing in mind the increased diameter of the disk, the effect is pro- bably equivalent to that obtained in air, and these preliminary experi- ments would tend to show that when a wooden disk is made to revolve rapidly at the surface of the earth, its radiation is increased to an extent depending on the velocity ; and it would appear that this effect is not materially less in a vacuum of 0'6 in. than in the open air. The authors intend to work out this and allied questions experimentally, and hope, if successful, to communicate the result to this Society. 1865.] T. A. Hirst on the Quadric Inversion of Plane Curves. 91 March 2, 1865. Major-General SABINE, President, in the Chair. In accordance with the Statutes, the names of the Candidates for election into the Society were read, as follows : — James Abernethy, Esq., C.E. A. Leith Adams, M.B. Alexander Armstrong, M.D. William Baird, M.D. George Bishop, Esq. John Charles Bucknill, M.D. Lieut.-Col. Cameron, R.E. Henry Christy, Esq. The Hon. James Cockle. The Rev. William Rutter Dawes. W. Boyd Dawkins, Esq. Henry Dircks, Esq. Thomas Rowe Edmonds, Esq. Professor Henry Fawcett. Peter Le Neve Foster, Esq. Sir Charles Fox, C.E. Archibald Geikie, Esq. George Gore, Esq. Professor Robert Grant. George Robert Gray, Esq. William Augustus Guy, M.B. Capt. Robert Wolseley Haig, R.A. George Harley, M.D. Benjamin Hobson, M.B. William Huggins, Esq. Fleeming Jenkin, Esq., C.E. Edmund C. Johnson, M.D. Henry Letheby, M.B. Professor Leone Levi. Waller Augustus Lewis, M.B. John Robinson M'Clean, Esq., C.E. Capt. Sir F. Leopold M'Clintock, R.N. Robert M'Donnell, M.D. Hugo Muller, Esq., Ph.D. Charles Murchison, M.D. Andrew Noble, Esq., C.E. Sir Joseph P. Olliffe, M.D. William Kitchen Parker, Esq. William Henry Perkin, Esq. Thomas Lamb Phipson, Esq., Ph.D. Charles Bland Radcliffe, M.D. Lovell Reeve, Esq. John Russell Reynolds, M.D. Thomas Richardson, Esq., Pli.D. Wm. Henry Leighton Russell, Esq. Edward Henry Sieveking, M.D. Alfred Tennyson, Esq., D.C.L. George Henry Kendrick Thwaites, Esq. The Rev. Henry Baker Tristram. Lieut.-Col. James Thomas Walker, R.E. A. T. Houghton Waters, M.D. Charles Wye Williams, Esq. Henry Worms, Esq. The following communications were read : — I. " On the Quadric Inversion of Plane Curves." By T. A. HIRST, F.R.S. Received February 16, 1865. Introduction. 1 . The method of inversion which forms the subject of the present paper is an immediate generalization of that now universally employed. In place of a fixed circle with the origin at its centre, any fixed conic (jpuubic) VOL. XIV. I 92 T. A. Hirst on the Quadric Inversion of Plane CuTves. [Mar. 2, whatever is taken, as a fundamental curve, and the origin is placed any- where in its plane. In this manner many descriptive relations which in the ordinary, theory are masked, regain the generality and prominence to which they are entitled. Having long ago convinced myself of the utility of this generalized method of inversion, I deem it desirahle to establish, for the sake of future reference, its chief general principles. With the view of securing the greatest possible familiarity with the effects of inversion, I employ 'purely geometrical considerations, and everywhere give preference to a direct and immediate contempktion of the several geometrical forms which present themselves. The examples occasionally introduced, are given for the sake of illustration merely ; they do not exhibit the full power of the method. Moreover, to prevent, as much as possible, the extension of a paper intended for publication in the Proceedings of the Royal Society, no attempt has been made to subject such special cases to exhaustive treatment. The figures are, for the most part, simple ; the fundamental one being given, the rest may readily be drawn or imagined ; when treating of the effects of inversion on the higher singularities of curves, however, I have thought it desirable to refer by the initials (91. (L) to articles and figures in Plucker's elaborate work on the Theorie der Algebraischen Curven. The relation which the present method bears to the still more general one of quadric transformation, as developed in 1832 by Steiner in his Geometrische Gestalten, and by Magnus in the eighth volume of Crelle's Journal, offers several points of interest to which I propose to return on a future occasion*. Definitions. 2. Two points, p and^', conjugate to each other with respect to a fixed fundamental conic (F), and likewise collinear with any fixed origin A in the plane of the latter, are said to be inverse to each other, relative to that conic and origin. In other words, the inverse of a point is the intersection of its polar, relative to (F), and the line which connects it with the origin A. From this the following property is at once deduced : i. The several pairs of inverse points p, p', on any line R through the origin A, form an involution, the foci of which are the intersections, real or imaginary, of that line and the fundamental conic (F). * I have recently been interested to find that the method of quadric inversion was distinctly suggested, though never developed, by Prof. Bellavitis of Padua no less than twenty-seven years ago. Considering the date of its appearance, the memoir, in the last paragraph of which this suggestion was made, is in many respects a remarkable one. It is entitled Saggio di Geomctria Derivata, and will be found in the fourth vo- lume of the Nuovi Saggi delP I. ft. Accad. di Science, Leffcre cd Arti di Padova. Two years previously, that is to say in 1836, the same geometer had developed, very fully, the principles of the ordinary method of cyclic inversion ; which latter, after a lapse of .seven years, appears to have been first proposed in England by Mr-. J. W. Stubbs, E.A., Fellow of Trinity College, Dublin, in a paper "On the Application of a new Method to the' Geometry of Curves nnd Curve Surfaces," published in the Philosophical Maga- zine, vol. xxiii. p. .3/W. 1865.] T. A. Hirst on the Quadric Inversion of Plane Curves. 93 Two curves are said to be inverse to each other, of course, when the se- veral points of one are inverse to those of the other. The latter is some- times referred to as the primitive, and the former as its inverse ; the relation hetween the two curves, however, is a mutual one, and the distinction is merely introduced for convenience. In order to obtain clear conceptions of the various relations which exist between inverse curves, it will be found convenient to place the origin A outside the fundamental conic (F). The modifications to be introduced when the origin is placed elsewhere are quite obvious, and, except in a few instances, need not be specially alluded to. 3. Adopting terms introduced by Magnus, the origin A and the two points of contact B and C of the tangents from A to the fundamental conic (F) are called the principal points ; the triangle, of which they form the corners, is termed the principal triangle, and its sides BC, CA, AB, respect- ively polar to A, C, B, are the principal lines. Occasionally it will be con- venient to refer to B and C as distinct from A, which is always real ; the two former will then be called the fundamental points, and the principal lines AB, AC, which there touch (F), will in like manner be called the fun- damental lines polar to B and C. 4. This premised, it is manifest from Art. 2 that, in general, a pointy has but one inverse pointy'. The only exceptions, in fact, are the three principal points, each of which is obviously inverse to every point in the principal line which constitutes its polar. It is further evident that each point of the fundamental conic (F) coincides with its own inverse, and that the several points of (F) are the only ones in the plane which possess" this property. Hence may be inferred, without difficulty, the following theorem : i. If any two curves have r-pointic contact with each other at a point p, not on a principal line, their inverse curves will also have r-pointic contact with each other at the inverse point p'. Relative orders of inverse Curves. 5. The order of the curve inverse to a given curve (P) of the order n i 2 94 T. A. Hirst on the Quadric Inversion of Plane Curves. [Mar. 2, may readily be ascertained. For in the first place, since (P) has n points on each principal line, its inverse must pass n times through each prin- cipal point (Art. 4) ; and secondly, since a line B drawn through the origin A intersects (P) in n points, none of which are, in general, situated on the principal line BC, polar to Aj the same line R will intersect the inverse curve, not only in the n points coincident with the origin, but also in n points distinct therefrom. Hence The complete quadric inverse of any curve of the order n is a curve of the order 2n, which has multiple points, of the order n, at each of the three principal points. 6. The term complete is here used because, under certain circumstances, the inverse curve will break up into one or more of the principal lines, each taken once or oftener, and aproper inverse curve (P') of lower order, and which passes less frequently through the principal points. This, by Art. 4, will be the case whenever the primitive curve (P) passes through a principal point; and it is obvious that the order of (P') will then be less than 2n by the total number of such passages. Further, the multiplicity of any principal point on (P') will be less than n by the number of times the two principal lines, which there intersect, enter into the complete inverse, — in other words by the number of passages of the primitive curve (P) through the poles of those principal lines. Hence, if ajjtt, c denote, respectively, the multiplicities of the principal points A, B, C on the curve (P), and if a', b', c' have the same significations relative to the inverse curve (P') of the order n', we shall have n'=2n— a — b— c, a'= n—b — c, b'= n-a-b, c'= n—a—c. These equations, by transformation, may readily be made identical with those which result therefrom by simply interchanging the accented and like non-accented letters; this shows, of course, that between proper inverse curves the same mutual relation exists as between inverse points. It is in virtue of this mutual relation that the theorems to be given hereafter are all conversely true ; the enunciations of the converse theorems may there- fore, in all cases, be omitted. 7. The above equations also furnish the following relations : nt—a'=n—a, n'—b'=n—c, n'—c'=n—b, from which we learn that i. The difference between the orders of two inverse curves is numerically the same as that between the order of either, and the total number of its passages through the three principal points. This latter difference, however, has opposite signs for the two curves. ii. For a curve to be of the same order as its inverse, and to pass the 1865.] T. A. Hirst on the Quadric Inversion of Plane Curves. 95 same number of times through each of the three principal points , it is neces- sary and sufficient, first, that its order be equal to the total number of its passages through the three principal points ; and secondly, that it pass as frequently through one fundamental point as through the other. It would be easy, by the second theorem, to determine the number and nature of the several curves of a given order which have inverse curves of the same order and like properties, relative to the principal points. This determination, however, as well as the solution of the allied question — Under what conditions will a curve of given order coincide with its own inverse ? will more appropriately form the subject of a separate paper. It will be sufficient to note here that a right line through the origin, and the fundamental conic itself, regarded as a primitive curve, are the simplest in- stances of the kind under consideration. Another example is also alluded to in Art. 11. Ex.3. Conies inverse to Right Lines, 8. From Arts. 2 and 6, as well as directly from elementary geometrical principles *, it follows that i. The inverse of a right line is, in general, a conic passing through the three principal points and the two intersections of the fundamental conic and the primitive line, as well as through the pole of the latter, relative to the former. It is only when the primitive line passes through a principal point that the inverse conic breaks up into the fixed principal line, polar to that point, and another right line (the proper inverse) through the principal point opposite to that fixed principal line (Art. 4). Thus : ii. The proper inverse of a right line passing through one of the two fundamental points is a right line passing through the other, and these inverse right lines always intersect on the fundamental conic. The following is an immediate consequence of this and the theorem i. of Art. 4 : iii. If one of two inverse curves have r-pointic contact, not on a principal line, with a right line passing through a fundamental point, the other will have r-pointic contact with the inverse line, through the other fundamental point, and the points of contact, being inverse to each other, will be collinear with the origin. The modification which this theorem suffers when one of the points of contact is on a principal line, will shortly be fully considered. 9. The line at infinity has also its inverse conic (I), which is of import- ance in many inquiries connected with inversion. On observing (Art. 2) that the inverse of the infinitely distant point of any line R through * An elegant demonstration of this theorem, identical with tlio elementary one alluded to, has been inserted by M. Chasles in Art. 209 of his excellent TraiU des Sec- tions Conigucs, the first part of which has just reached me. 96 Tf A. Hirst on the Quadric Inversion of Plane Curves. [Mar. 2, the origin is the middle point of the segment which (F) intercepts on R, and that (Art. 4) the infinitely distant points of (F) are necessarily also on (I), it will be seen thp.t i. The conic (I), circumscribed to the principal triangle, which is inverse to the line at infinity, is similar and similarly situated to the fundamental conic, of which latter, in fact, it bisects all chords that converge to the origin. By means of this conic (1) the asymptotes to any inverse curve may be readily constructed. Since the next article, however, will be devoted to the construction of the tangent at any point whatever of an inverse curve, it will be sufficient here to note the following obvious corollaries of the above theorem : ii. The asymptotes of either of two inverse curves are respectively parallel to the right lines connecting the origin with the intersections of the other curve and the conic (I), which circumscribes the principal triangle and is, at the same time, similar and similarly situated to the fundamental conic (F). iii. The conic inverse to a given right line will be a hyperbola, a parabola, or an ellipse, according as that line cuts, touches, or does not meet the conic (I), which circumscribes the primitive triangle and is similar and similarly placed to the fundamental conic (F). The conic (F) and the circle circumscribed to the " principal triangle ABC have, of course, conjugate to BC, a second common chord H, inverse to that circle (Art. 8, i.), and this chord is clearly the only line in the plane whose inverse is a circle. The imaginary intersections of H with (I) are inverse to the circular points at infinity, and consequently lie, with the latter, on a pair of imaginary lines intersecting in the origin A. Again, it is well known that all chords of (I) which subtend a right angle at A pass through a fixed point h*. The conies inverse to such chords are readily seen to be equilateral hyperbolas, and like their primitive lines they all pass through a fixed point — in fact, through the point h' inverse to h ; this point h', moreover, is well known to be the intersection of the three perpendiculars of the triangle ABC, about which all the equi- lateral hyperbolas are circumscribed f. It further follows from a known theorem, that the chords of (I) which subtend a constant angle at A envelope a conic which has double contact with (I) at the inverse circular points, or, in' other words, at the imaginary intersections of (I) and H ; and conversely that all tangents to such a conic intercept on (I) an arc which subtends at A a constant angle J. The conies inverse to such tangents are, when the latter actually cut (I), hyperbolas whose asymptotes are inclined to each other at a constant angle — that is to say (in order to embrace all cases), similar * Salmon's ' Conic Sections,' 4th ed., Art. 181, Ex. 2. f Ibid. Art. 228, Ex.1. Two distinct theorems in conies are thus brought, by inversion, into juxtaposition, and we have a simple example of the duality which this method, like that of reciprocal polars, imparts to every theorem. t Chasles's Sections Coniques, Arts, 473, 474; also Salmon's ' Conic Sections,' Arts. 2?6, 277, 296. 1865.] T. A. Hirst on the Quadric Inversion of Plane Curves. 97 conies. Now, by Arts. 4 and 6, the inverse of a conic which has double contact with (I) at the inverse circular points is, in general, a quartic curve having double points at A, B, C, and touching, at the circular points, the line at infinity. This curve, therefore, is also the envelope of similar conies circumscribed to the triangle ABC *. The point h clearly belongs to the above series of conies having double contact with (I), and H must be its polar relative to (I) -f; so that we may resume as follows*: iv. The right lines whose inverse conies are equilateral hyperbolas, all pass through the point h which is inverse to the intersection of the three perpendiculars of the principal triangle; the circle circumscribed to this triangle is the inverse of the polar H of the point h, relative to the conic (I) which is inverse to the line at infinity ; the imaginary intersections of H and (I) are the inverse circular points, and all lines which envelope a conic (S) having double contact at these points with the conic (I) are inverse to conies which are similar to each other. Tangents to inverse curves at inverse points. 10. To a pencil of right lines L, whose centre is p, corresponds, by quadric inversion, a pencil of conies (L') passing through the three prin- cipal points (Art. 8, i.) and the inverse point p'. To each element of the one pencil corresponds manifestly but one element of the other ; so that the lines L through p, and the tangents L', at p', to their respective inverse conies (L') constitute two homographic pencils]; ; and since two corresponding rays of the latter coincide with pp', every other pair must intersect on a fixed line D (see figure). Since, moreover, to the rays p B, p C correspond, respectively, the rays p' C, p' B (Art. 8, ii.), it is obvious that the line D is simply one of the three diagonals of the complete quadrilateral p Bp'C, the other two diagonals being pp1 and BC. Hence if a be the intersec- tion of the latter, the former D will, in virtue of a well-known property of the quadrilateral, pass through the harmonic conjugates d' and « of a, rela- tive respectively to pp' and BC. Now a is at once recognized to be the pole, relative to the fundamental conic, of pp' or R ; so that d, the inverse * From this a new definition may be readily deduced of the interesting curve, of the fourth order and third class (with three cusps, and the circular points for points of contact of an infinitely distant double tangent), which presented itself to Steiner as the envelope of the line passing through the feet of the perpendiculars let fall from any point of a circle upon the sides of an inscribed triangle, and of which he has enunciated (merely) so many remarkable properties in a paper published in vol. liii. of Crelle's Journal. The curve is, in fact, the envelope of an hyperbola circumscribed to an equilateral triangle, and having its asymptotes inclined to each other as are any two sides of that triangle. The curve may also be generated as a hypocycloid, and appears to be identical with the one whose equation is given at p. 214 of Dr. Salmon's ' Higher Plane Curves.' t Chasles's Sections Coniques, Art. 47-1. J Chasles, "Principe de correspondancc cntre deux ofy'efs variables," &c., Comptes Eendus, Dec. 24, 1855, and Sections Coniques, Art. 325. See also Cremona's ' Tcoria geometrica delle curve piane,' p. 7. 98 T. A. Hirst on the Quadric Inversion of Plane Curves. [Mar. 2, of d ', must be the pole of D or ad1, as well as the harmonic conjugate of A relative to^1 (Art. 2, i.). Consequently, from the fact that when L touches, at p, a primitive curve (P), the conic (L'), and hence its tangent L', must touch, aty, the inverse curve (Pf) (Art. 4, i.), we at once deduce the following theorem, by means of which the tangent at any point of a curve inverse to a given one may, for all positions of the origin, be readily con- structed : i. The tangents, at two inverse points, to two inverse curves intersect on the polar, relative to the fundamental conic, of the harmonic conjugate of the origin with respect to their points of contact. Hence we may also deduce the following property : ii. To a multiple point on one of two inverse curves, but not on a principal line, corresponds, on the other, a multiple point of the same order of multiplicity, and the tangents to corresponding (inverse) branches all intersect on the polar, relative to the fundamental conic, of the har- monic conjugate of the origin, relative to the two multiple points. The reality, taction, and general distribution of the several branches will be the same at two such multiple points ; the latter, in fact, will merely differ in certain secondary properties. For instance, a branch inflected at one of these points would not, in general, correspond to an inflected branch at the other ; the latter branch, however, would have three-pointic contact, at this multiple point, with the conic inverse to the tangent of the inflected branch at the first multiple point. 1 1 . The tangents at the principal points to two inverse curves may be thus investigated. Exclusive of the principal points JB and C, let the primitive curve (P) intersect the principal line BC in the points a, a1} a2, &c. . ., and conceive a right line R to rotate around the origin A. Exclusive of A this line R will intersect (P) in n— a points^?, respectively inverse to the n' — a' points p' in which it intersects the inverse curve (P') (Art. 7). It is clear, how- ever, that whenever, by the rotation of R, p approaches one of the points a, p' will approach to coincidence with A, so that R will there touch a branch of (P') ; and more generally, that if R should have (?•— l)~pointic contact at a with (P) it would, at the same time, have r-pointic contact at A with one of the branches of (P'). Similarly, if (P) intersect the fundamental line AC in the points ft, /3t, /32, &c. ., A and C being excluded, and a right line RI} turning around 15, intersect (P) in n—b points^*, their n' — c' inverse points^' (Art. 7) will be the intersections of (P') and the line R2, inverse to Rx and passing through C (Art. 8, ii.). Each pair of points^?, p', moreover, will be colliuear with A (Art. 2). Hence it follows that whenever, by the rotation of R, two points p and ft approach each other, the inverse point p' will approach C, so that the line R2 will there touch a branch of (P) ; and, as before, if Rt have (r— l)-pointic contact with(P) at a point ft, R2 will have r-pointic contact at C with a branch of (P'). 1865.] T. A. Hirst on the Quadric Inversion of Plane Curves. 99 In a similar manner the line ~R.,, which connects C and one of the inter- sections y of AB and (P), has for its inverse a line Rx touching, at B, a branch of (P'). All these cases are included in the following theorems : — i. The tangents at a principal point to one of two inverse curves are respectively inverse to the riaht lines which connect the intersections of the other curve and the principal line polar to that point, with the oppo- site principal point. ii. If a non-principal line have r-pointic contact at a principal point with any branch of one of two inverse curves, the inverse line ivill have (r—])-pointic contact with the other curve on t he principal line polar to that principal' point. The second of these theorems, as will be shown in the next article, is slightly modified when the line of ?'-pointic contact is a principal one ; the first theorem, though still true, becomes susceptible of the following simpler enunciation : iii. If a branch of one of two inverse curves touch a principal line at a principal point, the other curve will have a branch touched by the polar of this point at the pole of that line. The following examples will serve as illustrations of these three theorems : Ex. 1. The primitive being a right line intersecting the principal lines in a, ft, y, respectively (see figure), Aa will be the tangent at A to its inverse conic ; and if B/J, Cy intersect in p, the inverse point p' will be the pole of BC relative to the inverse conic. This pole is always real ; it may, more- over, be easily constructed, even when B and C are imaginary, on observing that p is also the intersection of the polar of a, relative to the fundamental conic, with the harmonic conjugate of aA, relative to BC and the primitive line. Ex. 2. The primitive being a conic passing through the origin and in- tersecting the fundamental lines in ft and y, its inverse will be a cubic passing through B and C, and having a double point at A (Art. 6). This latter point will be a node, if the primitive conic cut BC in real points a,, a2 ; and AaL, Aa3 will be the tangents thereat. It will be a conjugate or isolated point, however, when the primitive conic does not actually cut BC. The tangents to the cubic at B and C will, as before, intersect in the point p', inverse to the intersection p of B/3, Cy. If the primitive conic touch the latter lines in ft and y, in which case it is manifest that it cannot cut BC, then the cubic will have real points of inflection at B and C, and, necessarily, a conjugate point at A*. The line Ap is obviously the polar, relative to the primitive, as well as to the fundamental conic, of the intersection a of the lines BC, /3y ; hence aA touches the primitive conic at A, and, by i., a is a point on the cubic ; it is, in fact, the third point of in- flection on this curve. Ex. 3. The primitive being a conic touching the fundamental lines in * The truth of a well-known theorem in cubics, ' Higher Plane Curves' (Art. 183), is here rendered visible. 100 T. A. Hirst on the Quadric Inversion of Plane Curves. [Mar. 2, the fundamental points, the inverse curve will be another conic possessing the same properties (Art. 6). The fundamental conic is not the only one of such a series which coincides with its own inverse (Art. 7) ; for there is obviously a second one which cuts every line through the origin in a pair of inverse points. Singularities of inverse Curves. 1 2. If two of the intersections a, aL, a2 &c. . . of the primitive curve (P) with the principal line BC coincide ; in other words, if (P) touch BC at « ; then two of the branches of (P) will unite to form a cusp at A, at which A where E is the electromotive force. This equation expresses Ohm's law. Q=C*, (3) expressing a relation first proved by Faraday, where Q is the quantity of electricity conveyed or neutralized by the current in the time t. Finally, the whole system is rendered determinate by the condition that the unit length of the unit current must produce the unit force on the unit pole (Gauss) at the unit distance. If it is preferred to omit the conception of magnetism, this last statement is exactly equivalent to saying that the unit current conducted round two circles of unit area in vertical planes at right angles to each other, one circuit being at a great distance D above the other, will cause a couple to act between the circuits of a magnitude equal to the reciprocal of the cube of the distance D. This last relation expresses the proposal made by Weber for connecting the electric and magnetic measure. These four relations serve to define the four magnitudes R, C, Q, and E, without reference to any but the fundamental units of time, space, and mass ; and when reduced to these fundamental units, it will be found that the measurement of R involves simply a velocity, i. e. the quotient of a length by a time. It is for this reason that the absolute * Phil. Mag. Dec. 1851, 4th series, vol. ii. p. 551. 1865.] of Electrical Resistance. 159 measure of resistance is styled n e- or . precisely as the corn- second second mon non-absolute unit of work involving the product of a weight into a length is styled kilogrammetre or foot-pound. The Committee have chosen as fundamental units the second of time, the metre, and the mass of the Paris gramme. The metrical rather than the British system of units was selected, in the hope that the new unit might 'so find better- acceptance abroad, and with the feeling that while there is a possibility that we may accept foreign measures, there is no chance that the Continent will adopt ours. The unit of force is taken as the force capable of pro- ducing in one second a velocity of one metre per second in the mass of a Paris gramme, and the unit of work as that which would be done by the above force acting through one metre of space. These points are very fully explained in the British Association Report for ] 863, and in the Appendix C to that Report by Professor J. Clerk Maxwell and the writer. The magnitude of the— — ^ is far too small to be practically convenient, and the Committee have therefore, while adopting the system, chosen as their standard a decimal multiple 1010 times as great as Weber's unit /themillimetre\ Qr 1Q7 timeg ag ag ^ metre This m nitude \ second / second is not very different from Siemens' s mercury unit, which has been found convenient in practice. It is about the twenty-fifth part of the mile of No. 16 impure copper wire used as a standard by the Electric and Inter- national Company, and about once and a half Jacobi's unit*. It was found necessary to undertake entirely fresh experiments in order to determine the actual value of the abstract standard, and to express the same in a material standard which might form the basis of sets of resistance- coils to be used in the usual manner. These experiments, made during two years with two distinct sets of apparatus by Professor J. C. Maxwell and the writer, according to a plan devised by Professor W. Thomson, are fully described in the Reports to the British Association for 1863 and 1864. The results of the two series of experiments made in the two years agree within 0-2 per cent., and they show that the new standard does not pro- bably diifer from true absolute measure by 0' 1 per cent f. It is not far from the mean of a somewhat widely differing series of determinations by Weber. In order to avoid the inconvenience of a fluctuating standard, it is pro- posed that the new standard shall not be called " absolute measure," or described as so many — -- , but that it shall receive a distinctive name, seconds such as the B. A. unit, or, as Mr. Latimer Clark suggests, the " Ohmad," so * This last number may be 30 per cent, wrong, as the writer has never been in pos- session of an authenticated Jacobi standard, and has only arrived at a rough idea of its value by a series of published values which afford an indirect comparison. t Vide Appendix B. 160 Mr. F. Jenkin— Report on the New Unit [April 6, that, if hereafter improved methods of determination in absolute measure are discovered or better experiments made, the standard need not be changed, but a small coefficient of correction applied in those cases in which it is necessary to convert the B. A. measure into absolute measure. Every unit in popular use has a distinctive name ; we say feet or grains, not units of length or units of weight ; and it is in this way only that ambiguity can be avoided. There are many absolute measures, according as the foot and grain, the millimetre and milligramme, the metre and gramme, &c. are used as the basis of the system. Another chance of error arises from the possibility of a mistake in the decimal multiple used as standard. For all these reasons, as well as for convenience of expression, the writer would be glad if Mr. Clark's proposal were adopted and the unit called an Ohmad. Experiments have been made for the Committee by Dr. Matthiessen, to determine how far the permanency of material standards may be relied on, and under what conditions wires unaltered in dimension, in chemical composition, or in temperature change their resistance. Dr. Matthiessen has established that in some metals a partial annealing, diminishing their resistance, does take place, apparently due to age only. Other metals exhibit no alteration of this kind ; and no permanent change due to the passage of voltaic currents has been detected in any wires of any metal — a conclusion contrary to a belief which has very generally prevailed. The standard obtained has been expressed in platinum, in a gold-silver alloy, in a platinum-silver alloy, in a platinum-iridium alloy, and in mer- cury. Two equal standards have been prepared in each metal ; so that should time or accident cause a change in one or more, this change will be detected by reference to the others. The experiments and considerations which have led to the choice of the above materials are fully given in the Report to the British Association for 1864. The standards of solid metals are wires of from 0'5 millim. to 0'8 millim. diameter, and varying from one to two metres in length, insulated with white siik wound round a long hollow bobbin, and then saturated with solid paraffin. The long hollow form chosen allows the coils rapidly to assume the temperature of any surrounding medium, and they can be plunged, without injury, into a bath of water at the temperature at which they correctly express the standard. The mercury standards consist of two glass tubes about three-quarters of a metre in length. All these standards are equal to one another at some temperature stated on each coil, and lying between 14°'5 and 16°'5 C. None of them, when correct, differ more than 0'03 per cent, from their value at 15°-5 C. Serious errors have occasionally been introduced into observations by re- sistance at connexions between different parts of a voltaic circuit, as perfect metallic contact at these points is often prevented by oxide or dirt of some kind. Professor Thomson's method of inserting resistances in the Wheat- stone balance (differential measurer) has been adopted for the standards, but 1865.] of Electrical Resistance. 161 in the use of the copies which have been issued it has been thought that sufficient accuracy would be attained by the use of amalgamated mercury connexions. In the standards themselves permanence is the one paramount quality to be aimed at ; but in copies for practical use a material which changes little in resistance with change of temperature is very desirable, as other- wise much time is lost in waiting till coils have cooled after the passage of a current ; moreover large corrections have otherwise to be employed when the coils are used at various temperatures ; and these temperatures are fre- quently not known with perfect accuracy. German silver, a suitable mate- rial in this respect, and much used hitherto, has been found to alter in resistance, in some cases, without any known cause but the lapse of time, since the change has been observed where the wires were carefully protected against mechanical or chemical injury. A platinum-silver alloy has been preferred by the Committee to German silver for the copies which have been made of the standard. These have been adjusted by Dr. Matthiessen so as to be correct at some temperature not differing more than 1° from 150>5 C. The resistance of platinum-silver changes about O031 per cent, for each degree Centigrade within the limits of 5° above and below this temperature ; this change is even less than that of German silver. The new material seems also likely to be very permanent, as it is little affected by annealing. The form of the copies is the same as that of the standard, with the exception of the terminals, which are simple copper rods ending in an amalgamated surface. Twenty copies have been distributed gratis, and notices issued that others can be procured from the Committee for £2 10*. The Committee also propose to verify, at a small charge, any coils made by opticians, as is done for thermometers and barometers at Kew. Dr. Matthiessen reports, with reference to the question of reproduction, that given weights and dimensions of several pure metals might be em- ployed for this purpose if absolute care were taken. The reproduction, in this manner, of the mercury unit, as defined by Dr. Siemens, differs from the standards issued by him in 1864 about 8'2 per thousand if the same specific gravity of mercury be used for both observations*. Each observer uses for his final value the mean of several extremely accordant results. It is therefore to be hoped that the standard will never have to be reproduced by this or any similar method. On the other hand, four distinct observers, with four different apparatus, using four different pairs of standards issued respectively by Dr. Siemens and the Committee, give the B. A. unit as respectively equal to 1'0456, 1'0455, 1'0456, and 1-0457 of Siemens' s 1864 unit. It is certain that two resistances can be compared with an accuracy of one part in one hundred thousand — an accuracy wholly unattainable in any reproduction by weights and measures of a given body, or by fresh reference to experiments on the absolute resistance. The above four com- * If Dr. Matthiessen uses the sp. gr. of 13-596, as given by Kegnault, the difference from Dr. Siemens's standard is 5 per thousand. 162 Mr. F, Jenkin — Report on the New Unit [April 6, parisons, two of which were made by practical engineers, show how far the present practice and requirements differ from those of twenty and even ten years ago, when, although the change of resistance due to change of tem- perature was known, it was not thought necessary to specify the tempe- rature at which the copper or silver standard used was correct. The difficulty of reproducing a standard by simple reference to a pure metal, further shows the unsatisfactory nature of that system in which the con- ducting-power of substances is measured by comparison with that of some other body, such as silver or mercury. Dr. Matthiessen has frequently pointed out the discrepancies thus produced, although he has himself followed the same system pending the final selection of a unit of resistance. It is hoped that for the future this quality of materials will always be expressed as a specific resistance or specific conducting-power referred to the unit of mass or the unit of volume, and measured in terms of the standard unit resistance, that the words conducting-power will invariably be used to signify the reciprocal of resistance, and that the vague terms good and bad conductor or insulator will be replaced, in all writings aiming at scientific accuracy, by those exact measurements which can now be made with far greater ease than equally accurate measurements of length. There is every reason to believe that the new standard will be gladly accepted throughout Great Britain and the colonies. Indeed the only obstacle to its introduction arises from the difficulty of explaining to inquirers what the unit is. The writer has been so much perplexed by this simple question, finding himself unable to answer it without entering at large on the subject of electrical measurement, that he has been led to devise the following definitions, in which none but already established measures are referred to. The resistance of the absolute — -T is such that the current generated second in a circuit of that resistance by the electromotive force due to a straight bar 1 metre long moving across a magnetic field of unit intensity* per- pendicularly to the lines of force and to its own direction with a velocity of 1 metre per second, would, if doing no other work or equivalent of work, develope in that circuit in one second of time a total amount of heat equi- valent to one absolute unit of work — or sufficient heat, according to Dr. Joule's experiments, to heat 0*0002405 gramme of water at its maximum density 1° Centigrade. The new standard issued is as close an approximation as could be obtained by the Committee to a resistance ten million times as great as the absolute ,. The straight bar moving as described above in a second magnetic field of unit intensity, would require to move with a velocity of ten millions of metres per second to produce an electromotive force which would generate in a circuit of the resistance of the new standard the same * Gauss's definition. 1865.] of Electrical Resistance. 163 current as would be produced in the circuit of one j resistance by the second ' electromotive force due to the motion of the bar at a velocity of one metre per second. The velocity required to produce this particular current* being in each case proportional to the resistance of the circuit, may be used to measure that resistance, and the resistance of the B. A. unit may there- fore be said to be ten millions of metres per second, or 107 me re^. second It is feared that these statements are still too complex to fulfil the pur- pose of popular definitions, but they may serve at least to show how a real velocity may be used to measure a resistance by using the velocity with which, under certain circumstances, part of a circuit must be made to move in order to induce a given current in a circuit of the resistance to be mea- sured. That current in the absolute system is the unit current, and the work done by that unit current in the unit of time is equal to the resistance of the circuit, as results from the first equation stated above. Those who from this slight sketch may desire to know more of the subject will find full information in the Reports of the Committee to the British Association in 1862, 1863, and 1864. The Committee continue to act with the view of establishing and issuing the correlative units of current, electromotive force, quantity, and capacity, the standard apparatus for which will, it is proposed, be deposited at Kew along with the ten standards of resistance already constructed with the funds voted by the Royal Society. APPENDIX B. The following Table shows the degree of concordance obtained in the separate experiments used to determine the unit. The determinations were made by observing the deflections of a certain magnet when a coil revolved at a given speed, first in one direction, and then in the opposite direction. The first column shows the speed in each experiment ; the second shows the value of the B. A. unit in terms of 107 meires as calculated from the second single experiments. A difference constantly in one direction may be observed in the values obtained when the coil revolved different ways. This difference depended on a slight bias of the suspending thread in one direction. The third column shows the value of the B. A. unit calculated from the pair of experiments. The fourth shows the error of the pair from the mean value finally adopted. In the final mean adopted, the 1864 determination was allowed five times the weight allowed to that of 1863. * This current is the unit current, and, if doing no other work or equivalent of work, would develope, in a circuit of the resistance of the B. A unit, heat equivalent to ten millions of units of work, or enough to raise the temperature of 2405 grammes of water at its maximum density 1° Centigrade. 164 Mr. Schorlemmer on the Hydrocarbons [April 6, 1. Time of 100 revo- lutions of coil, in seconds. 2. Value of B. A. unit in terms of W ™£" second as calculated from each experiment. 3. Value from mean of each pair of experiments. 4. Percentage error of pair of observations from mean value. 17-54 17-58 1-0121 0-9836 0-9978 -0-22 77-62 76-17 1-0468 0-9613 1-0040 + 0-40 53-97 54-53 0-9985 0-9998 0-9992 —0-08 41-76 41-79 0-9915 0-5936 0-9925 -0-75 54-07 53-78 0-9961 0-9886 0-9924 -0-76 17-697 17-783 0-9878 1-0136 1-0007 + 0-07 17-81 17-78 0-9952 1-0174 1-0063 + 0-63 17-01 16-89 1-0191 ' 0-9895 1-0043 +0-43 21-35 21-38 1-0034 1-0011 1-0022 + 0-22 21-362 21-643 0-9968 1-0096 1-0040 + 0-40 11-247 16-737 1-0424 0-9707 0-9981 —0-19 Probable error of R (1864) , =0-1 per cent. Probable error of R (1863) =0-24 Difference in two values 1864 and 1863=0-16 Probable error of two experiments =0-08 „ II. " Researches on the Hydrocarbons of the Series Cn Ho,l+2." By C. SCHORLEMMER, Esq., Assistant in the Laboratory of Owens Col- lege, Manchester. Communicated by Prof. H. E. ROSCOE, F.R.S. Received March 21, 1865. Previously to the year 1848 none of the members of the numerous family of hydrocarbons of the general formula Cn H2ra+2, with the single exception of marsh-gas, were known to the chemist ; but since that year the re- searches of Kolbe on the electrolysis of the fatty acids, and those of Frank- land on the action of zinc upon the alcohol iodides, have opened up a new field of discovery, from which in rapid succession rich harvests have been reaped. The hydrocarbons thus isolated were considered by their dis- coverers to be the true radicals of the alcohols ; and in consequence the molecular weights which were then given to these bodies amounted only to half those which are now generally accepted. 1865.] of the Series Cn Il2n+2. 165 In their Report to the Paris Academy upon these hydrocarbons, Laurent and Gerhard t proposed that their formulae should be doubled, because these bodies, if represented by the smaller formulae, would in the gaseous state occupy two volumes instead of the four volumes in which the mole- cule of all other organic compounds was found to occur ; and they con- sidered these bodies as homologues of marsh-gas. Hofmann afterwards expressed himself in favour of the larger formulae on the same grounds, and also because, if Frankland's and Kolbe's formulae are accepted, the increase in the boiling-point produced by an increase of CH2 in the hydrocarbon would be double that which has been observed as the difference in the boiling-points of other homologous series. Besides these radicals, Frankland discovered another series of hydro- carbons, which, according to the mode of their formation, he regarded as the hydrides of the radicals, and as the true homologues of marsh-gas, and which, according to a view first propounded by Brodie, are considered to stand in a similar relation to the radical hydrocarbons as alcohol stands to ether, viz. — Hydride of ethyl. Ethyl. C2HS1 C2HA HJ C2H5| Alcohol. Ether. C255JO. r2TT5)° H/ C2HJ Brodie anticipated the existence of mixed radicals, as ethyl-amyl, Q2™5 [ , CHI bearing the same relation to the simple radical, n2 v( > as Williamson's mixed ether, & JJ5 i O, to common ether, n2 „« !• O. The researches of U5 Hu J t-'a 0-, J "Wurtz have fully realized this anticipation. Wurtz discovered a new method of preparing the alcohol radicals by the action of sodium upon the iodides ; and according to this method he not only obtained the hydro- carbons discovered by Kolbe and Frankland, but, by employing two dif- ferent iodides, he prepared a number of mixed radicals, which he also obtained by the electrolysis of a mixture of two fatty acids. The results of Wurtz' s investigation have always been regarded as a convincing proof of the correctness of Brodie's view, and it is now generally believed that two series of hydrocarbons of the formula Cn H2)l+3 exist, the hydrides and the radicals, the molecule of the latter containing two atoms of the real radicals which are supposed to exist in the alcohols. A very remarkable resemblance is observed in the general physical pro- perties of the two series, the members of which are gases or liquids so in- different as to resist even the action of concentrated sulphuric or nitric acids. This resemblance is so great that Greville Williams was led to the opinion that the indifferent hydrocarbons which he discovered in the oils obtained in the destructive distillation of Boghead coal belonged to the 166 Mr. Schorlemruer on the Hydrocarbons [April 6, series of the radicals, although he observed some differences in their physical properties. The chemical behaviour of the radicals has been very imperfectly studied, all experiments having failed which were carried out with the view of ob- taining from a radical either the alcohol from which it was derived, or the corresponding acid ; whilst, by the action of chlorine, only substitution-pro- ducts had been formed, in which 2 or 4 atoms of hydrogen are replaced by chlorine. The action of chlorine upon the hydrides had also been studied. Dumas showed that by acting upon marsh-gas, as first substitution-product the compound CH3 Cl was formed. Berthelot proved that this body was chloride of methyl, by converting it into methyl-alcohol and other methyl- compounds. From hydride of ethyl Frankland and Kolbe obtained the compound C2 H. Cl, which, however, appeared to them not to be identical, but only isomeric with chloride of ethyl. During the last few years, however, our knowledge of the hydrides has become much more complete. Pelouze and Cahours discovered the whole series, from hydride of butyl upwards, in the American petroleum ; Greville Williams proved the existence of hydride of amyl in the oils from Boghead coal, from which he inferred that the hydrocarbons formerly described as radicals were really hydrides ; and I found the same hydrocarbons in the products of the destructive distillation of Cannel-coal. From these researches it appears that the reaction by which Berthelot had obtained methyl-compounds from marsh-gas is a general one, and that from each hydride the corresponding chloride, the alcohol, and all their derivatives can be prepared. Whilst pursuing the investigation of the hydrides, I was struck by their close resemblance to the isomeric terms of the radical series, and I thought it might be possible that the opinion held by Laurent and Ger- hardt was, after all, the correct one, and that the so-called radicals belonged really to the marsh-gas hydrocarbons. Moreover Wurtz, by acting on zinc-ethyl with iodide of ally], had /"I TT I obtained the mixed radical ethyl-allyl, p2 « I =C5 HJO, which has not only *^3 **! I the composition, but all the characteristic properties of amylene, and Beilstein and Rieth had effected the synthesis of propylene and amylene by the action of zinc-ethyl upon chloroform. Might not the synthesis of the alcohol radicals be a synthesis of the same kind ? Or, if hydrides and radicals are really different, what is this difference? In order to solve this question I endeavoured to try if I could replace in a radical hydrocarbon 1 atom of hydrogen by chlorine, in order to compare these products and their derivatives with the chlorides and other derivatives obtained from the hydrides. As a starting-point I selected the mixed radical ethyl-amyl, because this hydrocarbon may easily be obtained in sufficient quantity, and because I 1865.] of the Series CnU2n+2. 167 had previously carefully studied the hydride of heptyl and its derivatives. In the preparation of ethyl-amyl a considerable quantity of the radical amyl is always formed, the behaviour of which with chlorine I also investi- gated. The first results of these researches have been published in the 'Journal of the Chemical Society,' vol. i. (new ser.) p. 425. I obtained the chlorides C7 H]5 Cl and C10 H21 Cl, which appeared to be identical with the chlorides of heptyl and of decatyl. The next step was to ascertain how the lower terms of the two series are acted upon by chlorine, and to study closely the differences which were stated to exist between methyl and hydride of ethyl. The results which I obtained were, however, quite dif- ferent from those of former observers. I found that when equal volumes of chlorine and of methyl, and equal volumes of chlorine and hydride of ethyl, are exposed to the diffused daylight, the principal product of the reaction consists in both cases of the compound C2 H5 Cl, a body having the composition and characteristic properties of chloride of ethyl, and as neither in the physical nor in the chemical properties of the two hydrocarbons a difference is known to exist, I concluded that methyl and hydride of ethyl are identical. It appeared very probable that the same relation might exist in the case of the higher terms of the two series, which, however, showed some differences in their physical properties, and I left it an open question whether there is only one series of hydrocarbons, Cn lH2n+2, or whether two series exist which exhibit the characters of physical isomerism. The following communication contains the results of researches carried out for the purpose of deciding the above question in the case of the hydro- carbons ethyl-amyl and hydride of heptyl, and of amyl and hydride of decatyl. The results of this investigation are in some respect not so com- plete as I could desire. The chief difficulty in working upon this subject is the very small yield of the alcohol of the series which is obtained from a proportionally large quantity of the hydrocarbon, the alcohol being cer- tainly that compound by the study of which and of its derivatives much light would be thrown on many still obscure points. Only, in the most favourable cases, one-third of the theoretical yield of the chloride is obtained ; and in preparing the acetate from the chloride a large quantity of the latter is decomposed into olefine and hydrochloric acid, and this decomposition increases as the compounds become richer in carbon. Thus a small fraction of the hydrocarbon is converted into the acetate ; and in order to prepare from this ether the pure anhydrous alcohol, losses are unavoidable, which diminish considerably the yield of a pure product. I have tried in different ways to obtain other compound ethers from the chloride, or to convert it into the iodide, without finding a better method than that originally employed, to which therefore I finally returned. The specific gravities given in the following account are compared with water at 4° C., or they give the weight of one cubic centimetre in grammes ; the boiling-points are provided with the necessary correction for the mercurial column above the vapour. 168 Mr. Scliorlemmer on the Hydrocarbons [April 6, I. Heptyl Compounds. The ethyl-amyl which is obtained by acting upon a mixture of the iodides of ethyl and amyl with sodium contains generally traces of ethyl- ether and ethyl-amyl-ether, the formation of which is easily explained by the presence of traces of moisture and amyl-alcohol, both of which can be completely excluded only with difficulty. In order to remove these ethers, I treated the crude ethyl-amyl, from which, by fractional distillation, the amyl was as much as possible separated, and which boiled between 70°- 120° C., with a mixture of concentrated nitric and sulphuric acids, by which not only the ethers, but also traces of iodides, which obstinately adhere, are removed. By washing with water, drying over caustic potash, and rectification over sodium, pure ethyl-amyl was obtained as a light mobile liquid possessing a faint ethereal odour which cannot be distinguished from that of hydride of heptyl. It boils at 90°-91° C., and has the spe- cific gravity 0'6819 at 17°'5 C. The boiling-point of the hydride of heptyl I have formerly stated as 98° C., whilst Pelouze and Cahours give it as 92°-94° C. I have lately convinced myself that the latter observation is the more correct one. The boiling-point of this hydrocarbon becomes lowered after being repeatedly treated with a mixture of nitric and sulphuric acids, by which traces of nitro-compounds of the benzol series of hydrocarbons are removed, which obstinately adhere*. Mr. Ch. R. Wright continued the fractional distillation of the hydride, which was very well purified in the above manner for a long time. In the beginning of these rectifications, the largest quantity of the liquid distilled between 95°-100°, whilst always a small quantity with a boiling-point above * Pelouze and Cahours state that the American petroleum which they used did not contain hydrocarbons of the henzol series, whilst I found a not inconsiderable quantity of these compounds in the rectified petroleum from which I isolated the hydrides. As it was not impossible that this was an accidental or intentional admixture, I endeavoured to procure some genuine crude American petroleum ; but I did not succeed in obtaining crude genuine Penusylvanian, as none of it had reached the Liverpool market for months. I however got some real Canadian rock-oil, as a thick black liquid of a very unpleasant odour. I distilled it, and treated the portion boiling below 150° C. with concentrated nitric acid, which acted violently. The acid liquid was then diluted with water, and heavy liquid nitro-compounds separated, possessing the odour of bitter almonds. These were treated with tin and hydrochloric acid, and the solution thus obtained was distilled with caustic potash. The aqueous distillate, in which some drops of an oily liquid were suspended, had the odour of aniline, and gave with a solution of bleaching-powder the most distinct aniline-reaction. The beautiful rosaniline-reaction could also easily be obtained by heating one of the oily drops with bichloride of mercury. Canadian petro- leum contains therefore the series of benzol hydrocarbons. In the preparation of hydride of decatyl from rectified petroleum, the portion boiling between 150°-170° was purified by nitric and sulphuric acids, and thus liquid and solid nitro-compounds obtained. The solid portion was several times recrystallized from alcohol, and the whole of the needle-shaped crystals thus obtained gave on analysis numbers very nearly agreeing with the formula of trinitro-cumol, C9 H9 (N02)3. 1865.] of the Series Cn H2n+2. 169 100° was left behind. As soon as such a residue ceased to be observed, the distillates were collected at intervals of 3°, and thus at last by far the largest quantity was found to boil constantly between 90°-92°. Whilst, however, the boiling-point was lowered, no change in the specific gravity was observed. The hydride of heptyl boiling at 90°-92° has the specific gravity 07148 at 15°, whilst that boiling at 98° gave the specific gravity 07149 at 15°-5. In the analysis and determination of the vapour-density of the hydrocarbon boiling at 90°-92°, Mr. Wright obtained the following data :— (1) 0*2047 substance gave 0*631 carbonic acid and 0'2935 water. (2) 0-2114 substance gave 0*6515 carbonic acid and 0-3030 water. Found. Calculated. T~ Ilf* C7 84 84-08 84-05 H16 16 15-93 15-93 100 100-01 99-98 (1) Balloon with air 6-8/55 Temperature of air 10° Balloon with vapour 7'0135 Temperature on sealing 162° Residual air 0'2 cub. centim. Capacity of balloon 88*9 cub. centim. (2) Balloon with air 8-3717 Temperature of air 11° Balloon with vapour 8*5661 Temperature on sealing 152° Capacity of balloon 1 19'3 cub. centim. Residual air 0 Vapour-density Found. calculated for ,. * N C7H16. I. II. 3-46 3*45 3-46 If a current of chlorine is passed into these hydrocarbons in diffused daylight, the gas is completely absorbed for some time, and the liquid assumes a yellow colour ; however, suddenly it becomes heated, torrents of hydrochloric acid are evolved, and the colour of the chlorine disappears, and from this point the chlorine acts quietly, and hydrochloric acid is con- tinuously evolved. If a little iodine has been added, the action continues in the dark, but higher chlorinated products are more easily formed. If 100-200 grammes of the hydrocarbon have been employed, the current of chlorine must be interrupted after some hours, and the liquid treated with solid caustic potash to remove the absorbed hydrochloric acid. The non- attacked hydrocarbon is then separated by distillation from the chlori- nated product, and the former treated repeatedly with chlorine, until all 170 Mr. Schorlemmer on the Hydrocarbons [April 6, the hydrocarbon has been acted upon. The product is then subjected to fractional distillation, in order to isolate the pure chloride C7 H15 Cl. The chloride of heptyl derived from ethyl-amyl boils at 146°-148°, and has the specific gravity 0' 88 14 at 16°-5. The chloride from the hydride has the boiling-point 148°-150°, and the specific gravity 0'9030 at 15°; the chloride from another preparation boiled at 147°-149°, and its specific gravity was found to be 0-8965 at 19°. By heating these chlorides in sealed glass tubes with acetate of potas- sium and glacial acetic acid to 160°-180°, chloride of potassium separates out, and heptylene and acetate of heptyl are formed. The point at which all the chloride has been decomposed can easily be recognized as follows : — Two layers of liquid are observed in the heated tube, the lower one con- sisting of a concentrated solution of acetate of potassium in acetic acid, and the upper one of chloride of heptyl with some acetic acid. Where these two layers meet, a separation of chloride of potassium takes place, and the crystals thus formed fall gradually through the lower part of the tube. As soon as this separation of the salt at the junction of the two layers ceases, the operation is finished. The contents of the tube are now diluted with water, the light liquid which separates is well washed, dried over chloride of calcium, and from this liquid heptylene and acetate of heptyl are separated by fractional distillation. The heptylene derived from ethyl-amyl, after repeated rectifications over sodium, was obtained as a colourless mobile liquid of a faint garlic-like odour, boiling at 93°-95°, and having the specific gravity 0'7060 at 12°*5. The analysis gave the following numbers : — 0-1799 substance gave 0*5640 carbonic acid and 0-2380 water. , Calculated. Found. CT 84 85-7 85-50 Hu JJ 14-3 14-64 98 100-0 100-14 The heptylene from hydride of heptyl, which I have previously de- scribed, boils at 95°-97°; but even after repeated distillations the boiling- point always rises to about 100° towards the end of the operation. Its specific gravity was found to be 0*7383 at 17°'5. I may here remark that all the compounds derived from the hydride which are mentioned in this paper are those formerly described (Journ. Chem. Soc. vol. i. new series, p. 216), being prepared from the hydrocarbon boiling at 98°. The boiling-point of the liquid from which the heptylene has been sepa- rated rises quickly above 170°, and at 180° it becomes constant, when pure acetate of heptyl distils over, giving on analysis the following results : — 0'2015 substance gave 0-5055 carbonic acid and 0-2090 water. Calculated. Found. Q, 108 68-35 68-42 H18 18 11-39 11-52 02 32 20-26 158 100-00 1865.] of the Series CnH2)I+2. 171 This ether possesses exactly the same pleasant smell of pears as that of the acetate from hydride of heptyl. The former boils at 178°-180°, and has the specific gravity 0*8707 at 160>5, whilst the boiling-point of the latter was found as 179°-181°, and the specific gravity 0'8868 at 19°. This ether is easily decomposed when heated with a concentrated solu- tion of caustic potash; heptyl- alcohol is formed, which, when dried over chloride of calcium, and treated with a small piece of sodium, in order to remove the last traces of moisture, was found to boil at 163°-165°. Its odour much resembles that of the hexyl-alcohol, but also reminds one of octyl-alcohol from castor-oil. The specific gravity is 0*8291 at 16°*5, whilst that of the hydride alcohol is 0'8479 at 16°, and its boiling-point 164°-165°. The odour of the latter is very similar to the alcohol from ethyl-amyl, but less pure, as if the true odour was interfered with by that of some other substance. The alcohol from ethyl-amyl was analyzed with the following results : — 0*2435 substance gave 0*6455 carbonic acid and 0*3075 water. Calculated. Found. C7 84 72-4 72-30 H16 16 13-8 14-03 O 16 13-8 116 100-0 Both alcohols dissolve easily in concentrated sulphuric acid : the mixture becomes hot and assumes a dark colour. After standing for some hours, a small quantity of tarry matter separates out on dilution with water, the clear liquid containing a sulpho-acid in solution, together with the excess of sulphuric acid. This mixture was neutralized with carbonate of barium, the liquid filtered, and evaporated to dryness in a water-bath. The dry residue was treated with water, and a barium salt dissolved, which however I did not succeed in obtaining crystallized from either of the alcohols, as the solutions, evaporated both in the water-bath and over sulphuric acid, yielded a thick syrupy liquid, drying slowly to a gum-like mass, in which no crystals could be detected, and which readily formed with the smallest quantity of water and alcohol clear solutions, which again, by spontaneous evaporation, dried into a gum. The smallness of the quantity of alcohol from ethyl-amyl at my disposal has for the present prevented me from repeating the experiment on a larger scale, which doubtless would have given a better result. In order to obtain the oxidation products of the two alcohols, they were distilled in a small retort with a mixture of bichromate of potassium and diluted sulphuric acid. A violent reaction occurs at first, which soon diminishes. The distillate was shaken with a solution of carbonate of sodium, and the liquid which did not dissolve treated again several times with the oxidizing mixture, and the distillate after each treatment shaken with the solution of carbonate of sodium. o2 ' 172 Mr. Schorlemmer on the Hydrocarbons [April 6, The solution of the sodium salt was evaporated to dryness in the water- bath, the residue distilled with diluted sulphuric acid, and the acid distillate, consisting of an aqueous liquid on which an oily layer swam, was rectified, in order to separate traces of sulphuric acid which had spirted over. The oily acid thus obtained possesses the odour of renanthylic acid, and consists entirely of this compound, as the following analyses of the silver-salt prove. (a) The acid derived from the hydride alcohol was neutralized with ammonia, and precipitated with a solution of nitrate of silver. The white flocculent precipitate was washed with cold distilled water, and dried care- fully at 100°, when it assumed a greyish colour. (1) 0-2084 of this salt gave 0'0948 silver. (2) 0-1600 of this salt gave 0'0731 silver. (3) 0*1375 of the salt recrystallized from water acidulated with nitric acid gave 0-0620 silver. (i) Acid from ethyl-amyl. (4) 0-2320 of the silver salt prepared as the salts in analyses 1 and 2 gave 0-1065 silver. (5) O'l 790 of silver salt obtained by neutralizing the acid with carbonate of silver gave 0-0816 silver. Found. Calculated for , • x , « s C7Hl3Aq02. I. II. III. IV. V. 45-57 %Aq. 45-49 45-69 45*09 45-73 45-59 In the oxidation of both of the alcohols a strong smell of oenanthol is observed. After treating the last distillate with sodium, a small quantity of an oily liquid remained undissolved, possessing the odour of cenanthol, and boiling between 150°-160°. These liquids gave a crystalline magma by shaking with a concentrated solution of bisulphite of sodium, a few drops of a liquid having a pleasant smell remaining undissolved. II. Decatyl Compounds. The amyl used in these researches was purified, in order to remove traces of amyl- ether and iodide of amyl, exactly in the same manner as ethyl-amyl. It boiled constantly at 158°-1 59°, and had the specific gravity 0-7275 at 14°. The hydride of decatyl was isolated from rectified American petroleum, after purifying the portion boiling between 1 50°- 1 70° by a mixture of concentrated nitric and sulphuric acids. It boiled at 1 5 7°-l 59°, and had the specific gravity 0- 746 1 at 14°. Pelouze and Cahours found the boiling- point of this hydrocarbon to be 160°, and its specific gravity 0735 at 15°. The same hydrocarbon was found by Greville Williams in the oils from Boghead coal, and described as amyl. He gives the boiling-point 159°, and the specific gravity 0'7365 at 18°. Amyl and the decatyl-hydride cannot be distinguished by their odour, which is exactly the same in the case of all the hydrides and the radical hydrocarbons, with the only difference that it is stronger the more volatile the substances are. 1865.] of the Series CnU2n+2. 173 In order to obtain the chlorides C10 H21 Cl, I proceeded in the same manner as described in the preparation of chloride of heptyl. The chloride of decatyl from amyl is a colourless mobile liquid of a pleasant, fruity smell ; it boils at 203°-205°, and has the specific gravity 0-8739 at 14°. The chloride prepared from hydride of decatyl boils at the same temperature, 203°-205° ; its specific gravity is 0'898 at 16*' 5. The odour of this chloride is fainter, not quite so pleasant, as if the true smell was hidden by that of some impurity. At first it possesses a yellowish colour, as Pelouze and Cahours have already observed; but it can be obtained quite colourless by repeated distillations, when a small quantity of a brown residue is always left behind. The analysis of the chloride from amyl I have already given in the pre- vious paper; that of the chloride from the hydride gave the following results : — 0-2857 substance gave 0-1938 chloride of silver and 0'0296 metallic silver. Calculated for ,, , C10HalCl. Found' 2 guished as b, c, d, e, f, going from stern to bow ; b abaft the mizen-mast, c immediately before the mizen-mast, d before the main-mast, e about the middle of the length, and f before the fore-mast : three on the main deck, ff, k, I; g halfway between the mizen and mainmasts, k below d, and I below/: two in the hold, near the centre of the ship, m and n : b being near the place where the neutral plane or rather the surface separating the part of the ship which displayed north magnetism from that which displayed south magnetism intersected the deck, was selected as a place for the standard compass, and a place was prepared for it by making there a false hatchway or compass platform, by replacing an iron beam by a wooden beam, and substituting wood planks for iron plates at that part of the deck. 6. From the observations, using the notation of the ' Admiralty Manual' (which has been translated into Russian by the author for the use of the Imperial Navy), by estimating the value of 2) and X, and making use of the formulae of the Manual, 2nd edit., p. 110, the author obtained from the observations made the following results : — Place Hor. force, Vert, force, Assumed. Computed. of H' Z' Compass. H' ¥•' 3). X. 33. • OC2H5 I OC2II5. Lactic ether. Ethylic amylohydroxalate. The two stages in the production of ethylic amylohydroxalate are ex- plained by the following equations : — C i - -, i c r\ TT n TT "i r* TT "i OZn C.X, +3H20=C2 J OH +2 Zn [ g g+^jf » } +°sjf " ] O. OC2H0- ^ 002H5 Ethylic amylo- Zinc Amyl Amylic alcohol. hydroxalak1. hydrate, hydride. 1865.] of the Lactic Series. 193 We have not attempted to give a name to the body from which ethylic amylohydroxalate is directly produced by the action of water, as shown in the last of the foregoing equations. The resources of chemical nomencla- ture, already too severely taxed, would scarcely be able to elaborate a rational name for this body, which consists of oxalic ether wherein an atom of oxygen is replaced, half by amyl and half by zincmonamyl, whilst a second atom of zincmonamyl is substituted for one of ethyl. Ethylic amylohydroxalate is a somewhat oily, transparent, and slightly straw-coloured liquid of specific gravity '9449 at 13° C., possessing a plea- sant aromatic odour and a burning taste. It boils at 203° C., and has a vapour-density of 5'47. The above formula requires 6'0, which is removed to an unusual extent from the experimental number. To this discrepancy we shall again refer presently. Section B of the oily liquid, after careful rectification, gave a product boiling at 224-225°, and yielded on analysis results agreeing with the formula CUH2203. This formula might be interpreted as that of ethylic amyloethoxalate, the rational formula of which would be OC2H3. We were at first inclined to regard this as the actual constitution of the new ether, believing it to be possible that ethylic oxalate and amylic iodide mutally decomposed each other, producing a mixture of amylic and ethylic oxalates with the iodides of amyl and ethyl. An analogous decomposition of mixed ethereal salts of oxygen acids has been recently noticed, but the test of experiment obliged us to abandon this view of the reaction. We found, it is true, a remarkable depression of temperature, amounting to 9*3° C., on mixing one atom of ethyl oxalate with one of amylic iodide, but on submitting the mixture to distillation, the thermometer rose to the boiling-point of amylic iodide (147°) before ebullition commenced ; thus showing that none of the much more volatile ethylic iodide had been formed. No transfer of radicals therefore takes place when ethylic oxalate is heated with amylic iodide, and consequently no zincethyl can be formed when this mixture is acted upon by zinc. We therefore prefer to view the ether now under consideration as ethylic ethyl-amylhydroxalate, analogous in constitution to Wurtz's ethylic ethyl lactate. |'C6H" CJ OC2HS CX OC2H5 to Mr- IOC, H.. IOC2H5. Ethylic ethyl lactate, Ethylic ethyl-amylhydroxalate. 194 Messrs. Frankland and Duppa — On the Acids [April 27, On this view, the following equations represent the formation of this ether. ,8c2H5 Iodide of ^OH Zincamylo- Ethyl oxalate. amyl< amylate. (Zn C- HH-I I H /~t TT *\ r r\ TT OO.E, +2H20=C2 j OC2H,+C|f"}+Zn"{gg O C2 H5 I O C2 H3 Hydride of Ethylic ethyl- amyl. amylhydroxalate. Ethylic ethyl-amylhydroxalate is a straw-coloured oily liquid, possessing an aromatic but somewhat amvlic odour and a burning taste. Its specific gravity was found to be '9399 at 1 3° C. It boils between 224° and 225° C. A determination of the sp. gr. of its vapour by Gay-Lussac's method gave the number 6'29, the above formula requiring 6'92. Section C of the oily product, boiling about 262° C., was next submitted to investigation. It gave results on analysis agreeing well with the formula C14H2803. The body is therefore ethylic diamyloxalate, the normal homologue of leucic ether, as seen from the following comparison : — f(C2H5)2 f(C.Hu), C JQH r OH 2 j O 2 1 O I OC2H5 IOC2H5 Leucic ether. Ethylic diamyloxalate. The production of ethylic diamyloxalate is explained by the following equations : — . O C2 Hs I OC2 H5 Zinc amylo- Ethylic oxalate. Amyl iodide. Ethylic zinc-mon- ethylate. amyl-diamyloxalate. Hu)2 c* o- V. O Cg Hg V. V \J2 •*-L5 Ethylic zincmonamyl- Ethylic diainyl- diamyloxalate. oxalate. Ethylic diamyloxalate closely resembles the two foregoing ethers in its appearance and properties. It is, however, a thicker oil, and flows less readily, and it has the lowest specific gravity of any ether belonging to this series, its density at 13° C. being only '9137. The following comparison of the specific gravities of all the ethers of this series shows that they generally increase inversely as their atomic weights. 1865.] of the Lactic Series. 195 Name. Formula. Sp. gr. Temp. Ethylic lactate C6 H10 O3 1-042 13 Ethylic dimethoxalate C6 H12 O3 0'9931 13 Ethylic ethyl lactate C7 Hu O3 0'9203 0 Ethylic ethomethoxalate C7 Hu O3 0-9768 13 Methylic diethoxalate C7 Hu O3 0-9896 . 16-5 Ethylic diethoxalate C8 H16 O3 0-9613 187 Ethylic amylhydroxalate C9 H18 O3 0'9449 13 Ethylic ethyl- amylhydroxalate Cu H22 O3 0'9399 13 Amylic diethoxalate Cu II22 O3 0*9322 13 Ethylic diamyloxalate C14 H2y O3 0-9137 13 Ethylic diamyloxalate boils at about 262°, and distils with little or no change. The specific gravity of its vapour was found to be only 5- 9 instead of 8'4. The investigation of these ethers has revealed a tendency to dissociation increasing with the weight of the atoms replacing the atom of oxygen in oxalic ether. Thus, beginning with lactic ether, which has the normal vapour-density, we find a gradual divergence culminating in ethylic diamyloxalate, as seen from the following series of numbers : — Vapour-densities. Name. Formula. ^ Calculated. Found. Ethylic lactate C5 H10O3 4-07 4-14 Ethylic dimethoxalate C6 H12 O3 4'56 4'67 Ethylic ethyl lactate C7 H14 O3 5'03 5-052 Ethylic ethomethoxalate C7 H14 O3 5-03 4'98 Methylic diethoxalate C7 H14O3 5'03 4'84 Ethylic diethoxalate C8 H16 O3 5-528 5'24 Ethylic amylhydroxalate C9 H18 O3 6-01 5'47 Ethylic ethyl-amylhydroxalate Cu Haa O, 6'92 6-29 Amylic diethoxalate CUH22O3 6-92 674 Ethylic diamyloxalate C14 H28 O3 8'4 5'9 We have likewise prepared the acids corresponding to the three ethers above mentioned. The first is obtained by decomposing ethylic amylhydroxalate with baryta, treating the solution of the barium-salt thus obtained with excess of sulphuric acid, and then dissolving out the organic acid with ether. On evaporating the ethereal solution, the acid remains as a thick oil which does not crystallize after several days' exposure over sul- phuric acid in vacua. The calcium- and barium-salts form white crystalline masses, which exhibit respectively the composition and i O Ca" 196 Messrs. Erankland and Duppa — On the Acids [April 27, We have also obtained a beautifully crystalline acid of the same com- position, and perfectly pure, from its zinc-salt, which is contained in the residue remaining after the distillation of the three ethers above described. Amylhydroxalic acid prepared from this zinc-salt is but sparingly soluble in water, from which, however, it crystallizes in magnificent nacreous scales that fuse at 60°'5 C., but afterwards remain liquid for some time even at ordinary temperatures ; they are very unctuous to the touch, and readily soluble in alcohol and ether. Several analyses gave results closely corre- sponding with the formula rc.Hn I H OH O OH. The barium-salt of this acid crystallizes in large and beautiful nacreous scales like paraffin, tolerably soluble in water, and exhibiting the composition (C5Hu)a We have also prepared a copper salt which is deposited from its aqueous solution in the form of minute light-blue scales, very sparingly soluble in water. The numbers obtained by the analysis of this salt agree with the formula (C5Hn)a By the decomposition of ethylic ethyl-amylhydroxalate with alcoholic potash, subsequent addition of sulphuric acid in excess, and treatment with ether, the corresponding acid was obtained as a thick oil, gradually solidify ing to a crystalline mass, which, however, did not appear to be in a fit state for the determination of its fusing-point. We have examined the barium- and silver-salts of this acid, which have respectively the following composition : — Barium ethyl- Silver ethyl- amylhydroxalate. amylhydroxalate. Ethylic diamyloxalate is readily decomposed by baryta- water. After removing the excess of baryta in the usual manner, barium diamyloxalate 1865.] of the Lactic Series. 197 crystallizes on evaporation in minute elastic needles, which, when dry, have the appearance of wool. It is moderately soluble in hot water, but sparingly so in cold. This salt gave numbers on analysis closely corre- sponding with the formula f(" If barium diamyloxalate be dissolved in hot dilute alcohol, and excess of sulphuric acid be added, the liquid after filtration contains diamyloxalic acid in solution. On heating upon a water-bath, the alcohol gradually evaporates, and diamyloxalic acid crystallizes in the hot solution as a beautiful network of brilliant silky fibres, which, after being well washed in cold water and dried at 100°, yielded on analysis numbers closely corre- sponding with the formula OH. Diamyloxalic acid presents the appearance of colourless satiny fibres, which are insoluble in water, but soluble in alcohol and ether. This acid is remarkable for its high melting-point, 122° C., in which respect it surpasses any of the acids of this series. Its melting-point is very sharply defined, and it solidifies immediately on a very slight reduction of tempera- ture. Heated more strongly, it sublimes and condenses on a cold surface in white crystalline flakes like snow. No. VI. Action of Zinc upon Amylic Oxalate and Ethylic Iodide. Equivalent proportions of amylic oxalate and ethylic iodide were digested at 50° to 60° C., with excess of granulated zinc, for several days. The reaction proceeded with extreme sluggishness, and was not completed before the expiration of a week. Being then mixed with water and submitted to distillation, an oily liquid passed over, which, on rectification, was ultimately resolved into amylic alcohol and an ethereal liquid, which analysis proved to be amylic leucate. The two consecutive reactions by which this body is produced are ex- pressed in the following equations : — 2 O loC5Hn Amylic oxalate. IOC5HU Amylic zincmonethyl leucate. Amylic leucate. 198 Messrs. Frankland and Duppa — Synthetical [April 27, Amylic leucate is a colourless, transparent, and slightly oily liquid, possessing a fragrant odour of a somewhat amylic character. It is insoluble in water, but miscible in all proportions with alcohol and ether. Its specific gravity is '93227 at 13° C. It boils constantly at 225° C., and its vapour has a density of 6'74 (theoretical 6*97). The boiling-point and specific gravity, in the liquid form, of amylic leu- cate and its isomer, ethylic amylethoxalate, are almost absolutely identical. Leucate of amyl is readily decomposed by either aqueous or alcoholic solutions of the alkalies, or by baryta-water, yielding amylic alcohol and a leucate of the base. No. VII. Action of Zinc upon a mixture of Amyl Oxalate and Amyl Iodide. When equivalent proportions of the amyl iodide and amyl oxalate are heated gently in contact with zinc, a brisk reaction soon sets in. After evolving much hydride of amyl and amylene, the whole solidifies to a gum-like mass, which, on distillation with water, yields an oily liquid resembling that obtained when ethyl oxalate is employed. We have every reason to believe that the same series of ethers as those described in note No. V. are here produced, with the difference that they are amylic, instead of ethylic ethers. This difference of base, however, renders it impossible successfully to separate these ethers from each other, their boiling-points being so high as to determine decomposition when their distillation is attempted. We might, it is true, have decomposed the mixed ethers with solution of baryta, and thus have obtained the mixed acids, but the task of disentangling the latter appeared also so hopeless, that we have not attempted it. IV. " Notes of Synthetical Researches on Ethers.— No. I. Synthesis of Butyric and Caproic Ethers from Acetic Ether." By EDWARD FRANKLAND, F.R.S., and B. F. DUPPA, Esq. Received April 5, 1865. For some time past we have been engaged in the study of the consecutive action of sodium and the iodides of methyl and ethyl upon acetic ether. When iodide of methyl is used, the chief products of the reaction are two ethereal bodies possessing respectively formulae, which we will provisionally write as follows : — C 0"! CO") C4H7l02 and C5H9lO2. C.H.J C2H5J These bodies are decomposed,"even in the cold, by baryta-water, yielding barium carbonate, alcohol, and two new ethereal liquids having formulae which, without expressing any opinion as to their nature or constitution, may be thus written : — 1865.] Researches on Ethers.— No. I. 199 We have also obtained corresponding results by tbe employment of iodide of ethyl in place of iodide of methyl, and are now occupied in the preparation of a paper containing the details of this investigation, which we hope very soon to have the honour of laying before the Royal Society*. In the meantime, however, some of our results are so remark- able that we hasten to communicate them at once in this preliminary note. It has been proved by Kolbe and Frankland, nearly twenty years ago, that methyl is a constituent of acetic acidf, and in the year 1857 these chemists were the first to propose the derivation of this and a large number of other organic compounds from the carbonic acid or tetratomic carbon typej. According to this view, which is now gradually receiving the assent of chemists, the rational formula of acetic ether is CH3 O C2Hg, or, with the formula of the contained atom of methyl fully developed, [H rgfg c J" IOC2H, Thus the radical methyl, in acetic ether, contains three single atoms of hydrogen, combined with a tetratomic atom of carbon. If one of these atoms of hydrogen be replaced by methyl, an ether, having the composition of propionic ether, will obviously be produced : rc(CI' H J H [OC2H5. If a second atom of hydrogen be replaced by another atom of methyl, butyric ether or its isomer will, in like manner, be formed : "1 O l()CaHa. * Whilst engaged in these experiments we became aware, through the ' Jahresbericht der Chemie,' that the reaction had already been studied by Geuther, who, however, owing to his having conducted the process in a somewhat different manner, obtained only two of the compounds above mentioned, viz. the body Cj H12 O3 by the action of sodium and iodide of methyl upon acetic ether, and the compound C,, H14 O3 in the corresponding reaction with iodide of ethyl. t Memoirs and Proceedings of the Chem. Soc. vol. iii. p. 386; and Ann. der Ch. und Pharm. Bd. Ixv. S. 288, imd Bd. Ixix. S. 258. J Ann. der Ch. und Pharm. Bd. ci. S. 2GO. 200 Messrs. Frankland and Duppa— Synthetical [April 27, An ether, of the same composition as the last, will also obviously result, if, instead of replacing two atoms of hydrogen by two of methyl, one of those atoms be substituted by one of ethyl, 2H5 O lOC2H5. Again, if two atoms of hydrogen in the methyl of acetic ether be replaced by two of ethyl, caproic ether should result : C2H5 C,H5 .OC2H5. And, finally, if all three atoms of hydrogen be replaced by amyl, there must be produced the ether of an acid possessing the atomic weight of margaric acid : c r H rrJr H [ C < Cs Hu C! Cc Hu 1 o IOC2H5. It is unnecessary to follow theoretically these reactions further ; but it is obvious, from what has been already advanced, that, by a proper selection of the three radicals put into the place of the methylic hydrogen, any ether, from the margaric downwards, can be produced at will, by a process analogous to that which we have experimentally demonstrated in the lactic series. The present note describes the method by which we have already realized several of these substitutions. Synthesis of Butyric Ether. When sodium is gently heated with acetic ether, it gradually dissolves with evolution of hydrogen, and on cooling, the liquid solidifies to a crystal- line mass, which becomes hot when mixed with iodide of ethyl, abundance of iodide of sodium being formed : nevertheless it is advisable to complete the reaction by enclosing the materials in a digester, and then heating the latter for several hours to 100°C. On distilling the crude product thus obtained with water, a large quantity of an ethereal liquid collects upon the surface of the aqueous portion of the distillate. After drying with chloride of calcium, this liquid begins to boil at about 40° C., when a considerable amount of ethylic ether comes over. Afterwards the temperature rises to 70°, between which point and 80° some acetic ether, which had escaped the action of the sodium, distils. The remainder of the distillate, which 1865.] Researches on Ethws. — No. I. 201 was collected apart, came over between 80° and 250°. By repeated rectification, in addition to other products, which belong to another part of the investigation, two liquids were obtained in considerable quantity, one of which boiled at 1 18°-122°, and the other at about 150°-157° C. On treating these liquids with boiling baryta- water for' several hours, the point of ebullition of the first was rendered quite constant at 119°, and that of the second at 151°. Submitted to analysis, the first of these liquids yielded results closely coinciding with those calculated from the formula of butyric ether, The boiling-point of the new ether also coincides exactly with that of butyric ether, as does also its vapour-density, which was found to be 3'96, the vapour-density of butyric ether being 4'04. Its density in the liquid state is -8942 at 0°C., that of butyric ether being '9019 at 0° C. The synthesized butyric ether is readily decomposed by alcoholic potash, yielding alcohol and a salt which, when distilled with excess of sulphuric acid, gives a powerfully acid oily liquid, tolerably soluble in water, possessing in a high degree the characteristic odour of butyric acid, and boiling fixedly at 161°C. The boiling-point of butyric acid has been variously stated by different observers: Pelouze and Ge'lis give it as 164°, whilst H. Kopp makes it 157°, at 760 millims. pressure. This acid gave numbers, on analysis, exactly corresponding with the formula fC3H7 C\ O [OH. Boiled with water and silver carbonate, it yields, after some hours, a crop of beautiful ramiform needle-like crystals, aggregated into large globular masses, which become anhydrous in vacuo ; both the mother-liquor and crystals have a faint smell of rancid butter. Submitted to analysis they yielded results closely corresponding with those required for butyrate of silver, C3H7 O We reserve for a future communication the decision of the question as to whether the butyric acid thus obtained is identical with that produced by the process of fermentation ; but we may now state that the synthesized butyric ether possesses, in a very dilute form, a fruity smell, but differing in this respect somewhat from that of the butyric ether ordinarily sold as essence of pine-apples. We have also reproduced the ether from the baryta- salt with the same result as regards odour. The production of butyric from acetic ether, by the consecutive action of sodium and iodide of ethyl, is expressed by the following equations : — 202 Messrs. Frankland and Duppa— Synthetical [April 27, H fNa Ire | H Q^H + Na2=2C JH + H2 OC2H5 IOC2H5. Acetic ether. Sodacetic ether. H+NaI OC.H.. Butyric, or ethacetic ether. It has been already stated above that an acid of the same composition as butyric acid must also result from the replacement of two atoms of hydro- gen, in the methyl of acetic ether, by two of methyl ; and we have in fact produced this acid by first replacing the two atoms of hydrogen by sodium, and then acting upon this compound with iodide of methyl : — Na + 2NaI OC2H5 Butyric, or dimethaeetic ether. We have not yet obtained this ether in a state of perfect purity ; but by acting upon the crude product of the reaction with alcoholic potash, a mixture of potassium acetate and butyrate was obtained, and yielded, by the application of Liebig's admirable method of partial saturation, butyric acid in a state of such purity that a further semisaturation produced no change in its composition. A barium salt and a silver salt made from this acid yielded results on analysis closely corresponding with the for- mulae f2C CH, Q, J Barium butyrate, or dimethacetate. Silver butyrate, or dimethacetate. It is thus evident that an acid, having the composition of butyric acid, can be now produced by three distinct synthetical processes, viz. 1st, by 1865.] Researches on Ethers.— No. I. 203 the introduction of propyl into carbonic acid ; 2ndly, by the substitution of ethyl for hydrogen in acetic ether ; and Srdly, by the replacement of hydrogen by methyl in acetic ether. The ethers of these acids may be thus represented : — C3H7 rcH3 h° oc3H5 o ) cr [OC2H5 Propyl-carbouic ether. Ethacetic ether. Dimethacetic ether. Are these acids identical, or are they isomeric? We hope shortly to be able to answer this question decisively. Synthesis of Caproic Ether. The production of a dimethacetic compound, as above described, obviously points out a reaction by which caproic or diethacetic ether can be obtained. It is only necessary to act upon disodacetic ether with iodide of ethyl, to obtain, with the greatest facility, the compound in question : — C2H5 C2H3 a+2NaI .OO.H. OC2H5 Disodacetic ether. Diethacetic or caproic ether. Diethacetic ether boils constantly at 151° C. The boiling-point of ordinary caproic ether is stated by Lerch to be 120°, and by Fehling 162°. These numbers differ so widely that it is impossible to use them for com- parison. Its specific gravity at 0° C. is '8822 (according to Fehling the density of caproic ether is '882 at 18° C.), and its vapour-density 5 '00, the theoretical number being 4'98. On analysis it yielded numbers corresponding with the above formula. Diethacetic ether possesses a peculiar and somewhat pleasant odour, somewhat resembling oil of pepper- mint ; it is insoluble in water, but miscible in all proportions with alcohol and ether. Treated with alcoholic potash it is readily decomposed, yielding alcohol and potassium diethacetate, and by distilling the latter with dilute sulphuric acid, diethacetic acid distils over and floats on the surface of the water which accompanies it. This acid reddens litmus- paper powerfully, is very sparingly soluble in water, and emits a peculiar odour, quite different from that of ordinary caproic acid. Boiled with water and carbonate of silver it yields, on filtration and evaporation in vacuo, splendid fern-like crystals, which, after pressing between folds of blotting-paper and drying in vacuo, with the exclusion of light, are perfectly white, with a satiny lustre ; they possess great elasticity, and are remark- ably like asbestos. In a strong light they rapidly become brown. Sub- VOL. XIV. R 204 Mr. G. Gore on the Properties of [May 4, mitted to analysis this salt exhibited the composition required by the formula 0 lOAg. Diethacetate of silver differs from the silver salt of the caproic acid pre- pared from cyanide of amyl, by its much greater solubility in water, and by its ramiform crystallization, amylic caproate of silver crystallizing in large and very thin plates, which are nearly insoluble in cold water. In conclusion, there can be no doubt that this reaction is capable of a very wide extension, and that, by its means, we shall be able to ascend many of the well-recognized homologous series. Whilst pursuing it in the acetic and benzoic series of ethereal salts, we also purpose to extend it to the alcohols and ethers. May 4, 1865. Major-General SABINE, President, in the Chair. In compliance with the Statutes, the names of the Candidates recom- mended for election into the Society were read from the Chair, as follows : — Henry Christy, Esq. The Hon. James Cockle, M.A. Rev. William Rutter Dawes. Archibald Geikie, Esq. George Gore, Esq. Robert Grant, Esq., M.A. George Robert Gray, Esq. George Harley, M.D. William Huggins, Esq. Sir F. Leopold McClintock, Capt. R.N. Robert McDonnell, M.D. William Kitchen Parker, Esq. Alfred Tennyson, Esq., D.C.L. George Henry Kendrick Thwaites, Esq. Lieut.-Col. James Thomas Walker, R.E. David Livingstone, LL.D., and the Right Honourable Lord Dufferin were admitted into the Society. The following communications were read : — I. " On the Properties of Liquefied Hydrochloric Acid Gas." By GEORGE GORE, Esq. Communicated by Professor STORES, Sec. R.S. Received March 30, 1865. In a former communication to the Royal Society " On the Properties of Liquefied Carbonic Acid," printed in the Philosophical Transactions for 1861 (also in the Journal of the Chemical Society, vol. xv., page 1C3)*, * The reader is referred to the above communication for details of information respecting the apparatus employed and manipulation adopted. 1865.] Liquefied Hydrochloric Acid Gas. 205 I described a mode of manipulation whereby various solid substances were introduced into that liquefied gas whilst under very great pressures (vary- ing from 500 to 1100 pounds per square inch), and the action of the liquid upon them observed. The experiments described in the present paper were made in a similar manner, but with some improvements in safety of manipulation, and in the mode of discharging the tubes, so as to recover the immersed solids in a satisfactory state. The glass tubes in which the gas was condensed were about y^ths of an inch internal diameter, and fully -f ths of an inch external diameter. Each tube was, before bending, 11^ inches long; it was bent, at 1^ inch and 6\ inches respectively from one end, to the form already described in the paper referred to, thus giving 5 inches in length for the salt, 5 inches for the acid, and 1^- inch for the liquefied gas. These distances are essen- tial ; for if the quantities of acid and salt are not properly proportioned to each other, and to the remaining space in the tube, the liquefied product will be very small. The curve in the tube between the acid and the salt should be very gradual, and the other bend much less so. The end of the tube containing the salt should be constructed open, with a flange, and be closed securely by a plug of gutta percha in the same manner as the upper end. The materials used were strong sulphuric acid and fragments of sal- ammoniac. Each tube was placed in a deal frame or box 10 inches high, 8 inches wide, and 4 inches from front to back, open at the back, and with a front or door of wire gauze. The tube was supported by a cork fitting into a hole in the side of the frame, and was secured within a notch in the cork by a ligature of wire. By means of this arrangement the acid and salt were brought into mutual contact by turning the box itself, with- out incurring the danger of putting one's hand inside the box and turning the tube alone, as in the former experiments. The annexed figures (1 & 2) represent the position of the box, 1st, when charged and ready for the decomposition of the sal-ammoniac ; and 2nd, after the decomposition is completed. The arrows indicate the direction in which the box is turned. The action at first should be very slow ; otherwise the bubbles of gas will convey the sulphuric acid into the short end of the tube, and endanger the purity of the liquefied hydrochloric acid. The action of the acid was less violent than when generating carbonic acid, and the process was less frequently stopped by clogging of the tube. The liquefied gas was condensed in contact with the various solid bodies by application (from behind) of cotton wool, wetted with ether, to the short end of the tube, as in the former experiments. Each tube was discharged of its contents by taking hold of it with an ordinary wooden screw clamp support, and immersing its lower end in a vessel of nearly boiling water behind a protecting screen. The explosion R2 206 Mr. G. Gore on the Properties of [May 4, quickly occurred, generally without fracture of the tube, and the sub- stances operated upon could in nearly all cases be readily extracted for examination without suffering injury by coming into contact with the saline contents of the tube. Powdered substances, however, were frequently lost during the discharge, owing to the sudden expansion of the gas in their pores expelling them from the small glass cup. The great degree of pressure (probably about 700 pounds per square inch and upwards) to which the various substances were subjected, frequently made them very hard. Kg. 1. Fig. 2. The chief inconvenience met with in these experiments arose from the action of the liquefied acid upon the upper gutta-percha stopper, causing the acid to become dark red-brown and opaque, and preventing accurate observation of the substances — also, on discharge of the tube, causing the glass cup and its contents to become coated with a tenacious film of gutta percha. To obviate this inconvenience as much as possible, the inner end of the upper stopper was carefully coated with melted paraffin. During the early part of each experiment, the liquefied acid was repeatedly poured back, and redistilled by the application of ether, in order to free it from colour imparted to it by the stopper, and also to make its solvent or other action upon the immersed body more rapid. The action of the liquid acid upon the bodies was only continued a few days ; and in many cases the acid was not in a liquid state the whole of the time, but only at intervals ; in all cases, however, the period of immersion was abundantly sufficient for the liquefied acid to produce its full effect. The effects in nearly all cases were of so distinct a character, and the conditions under which they were produced so definite, as not to require repetitions of the experiments ; but those which were in any respect uncertain were repeated, and those also which were of an important or striking character were likewise repeated, in order to remove the least shadow of a doubt that might be raised respecting them. 1865.] Liquefied Hydrochloric Acid Gas. 207 The liquid acid is a very feeble conductor of electricity. Two fine platinum wires, immersed in it f ths of an inch in length and y^-th of an inch asunder, and connected with a series of 10 Smee's elements, evolved no perceptible bubbles of gas, and produced only a moderate deflection (amounting to 23 degrees) of the needles of a sensitive galvanometer ; and this amount of conduction might possibly have been due to a minute trace of oil of vitriol mixed with the liquid acid. In a second similar experi- ment, with the wires y^th of an inch apart, not the slightest conduction occurred on using the same battery-power, but by employing the secondary current of a strong induction-coil with condenser attached, conduction and a steady deflection of the needles of the galvanometer (26 degrees) took place, gas being freely evolved from the negative wire only. On separating the brass points of the secondary terminals beyond the distance of the thickness of a thin address card, sparks ceased to pass between those points, and gas was evolved copiously in the liquid acid, apparently in the mass of the acid between the two platinum wires as well as at the wires themselves ; two similar platinum wires in dilute hydrochloric acid in the same circuit evolved very little gas. It is probable that much of the gas evolved in the liquefied acid was not a product of electrolysis, but simply the acid itself volatilized by the thermic or other action of the current. No sparks occurred at any time in the liquid acid. It is evident there- fore that liquefied hydrochloric acid gas is a very bad conductor of elec- tricity, but it is not nearly so powerful an insulator as liquefied carbonic acid gas. The following experiments illustrate its chemical, solvent, or other action upon various substances immersed in it. The quantity of the solid substances employed was in nearly all cases very small in proportion to that of the liquid acid in contact with them, and in many cases did not amount to one-twentieth of its volume. A piece of charcoal remained unchanged at the end of ten days, the acid being in a liquid state in contact with it at intervals. A fragment of fused boracic acid did not lessen in bulk or alter in appearance in seven clays. White phosphorus was undissolved and unchanged in nine days, and remained equally inflammable. A fragment of ordinary sulphur did not dissolve or alter in several days. Fragments of vitreous black selenium did not dissolve or change in six days. Iodine dissolved rather freely, and quickly formed a purple-red solution. A piece of pentachlo- ride of phosphorus softened in the gaseous acid, and dissolved quickly and completely in the liquid acid, forming a colourless solution. A fragment of sesquicarbonate of ammonia swelled and became full of fissures in the gaseous acid, but neither evolved gas nor dissolved when the liquid acid came into contact with it ; after three days' intermittent immersion in the liquid acid, the saline residue evolved no gas on immersion in dilute hydro- chloric acid. A piece of sal-ammoniac, immersed almost constantly du- ring nine days, remained undissolved and unchanged. 208 Mr. G. Gore on the Properties of [May 4, Potassium evolved no gas when the liquid acid came into contact with it ; after eight days it was sometimes enlarged in bulk, and from the outset it was of a white colour ; it did not at all dissolve. In a second experiment the results were precisely similar ; after three days' intermittent immersion the saline residue showed no signs of containing free potassium on immersing it in dilute hydrochloric acid. Anhydrous carbonate of potash in powder evolved no gas on first coming into contact with the liquid acid ; after three days' occasional immersion it remained undissolved, and the residue evolved no carbonic acid on immersion in dilute hydrochloric acid. A crystal of chloride of potassium did not dissolve or change in appearance by four hours' immersion in the liquefied acid. Powdered chlorate of potash imparted a yellow colour to the liquid acid, and did not lessen in bulk during three days' constant immersion ; the upper gutta-percha stopper became quite white at its inner end. A crystal of nitrate of pot- ash became of a brownish colour before the gas liquefied, and remained undissolved after six days' intermittent immersion ; the upper gutta-percha stopper was unusully acted upon, and of a nankeen colour. Sodium became white and swelled largely before the gas liquefied. No visible gas was evolved by it in the liquid acid. After three days' inter- mittent immersion the residue contained no sodium in the metallic state, and no portionof it imparted a blue colour to damp litmus paper. Anhydrous carbonate of soda in powder immersed one hour and a quarter in the liquid acid evolved no visible bubbles of gas, and lost its alkaline reaction (with litmus paper) to about three-fourths of its depth. A fragment of 'fused sulphide of sodium produced a slight sublimate of a yellowish- white colour in the gaseous acid, and turned of a yellowish-white colour. It evolved no visible gas in the liquefied acid*. After three days' variable immersion it was of a yellowish-white colour, and somewhat enlarged in bulk ; the residue evolved no sulphuretted hydrogen by immersion in dilute hydrochloric acid, and its solution gave a perfectly white precipitate with acetate of lead, and imparted no dark colour to sulphate of copper. Precipitated carbonate of baryta in powder evolved no visible gas by immersion in the liquid acid ; it remained undissolved and unchanged in appearance during three days' immersion ; the residue evolved a minute quantity of gas by contact with dilute hydrochloric acid. Precipitated carbonate of strontia in powder behaved like carbonate of baryta ; the residue, after three days' immersion, was lost during the discharge. A minute fragment of anhydrous Bristol lime exhibited no solution or altera- tion by nearly constant immersion during eight days in the liquid acid. On removal from the tube, it imparted a strong blue colour to neutral litmus paper by slight friction. On fracture it was found similarly alka- * Probably the sulphuretted hydrogen set free was in a liquid state, and therefore no bubbles of gas appeared. I found by experiment that hydrochloric acid and hydrosul- phuric acid, generated together and condensed into a liquid state, did not form two separate strata of liquid. 1865.] Liquefied Hydrochloric Acid Gas. 209 line throughout, and exhibited a slight change of colour, extending from its surface to the centre, as if the gas or liquid had been forced into its pores. In a second experiment of three days' intermittent immersion, precisely similar effects were obtained. Several minute fragments of very soft marble were immersed in the liquid acid at intervals during seven days. No gas was evolved when the liquid touched them. On removal from the acid, their physical characters appeared unaltered ; they were insoluble in water, but quickly dissolved in dilute hydrochloric acid, with copious evolution of gas. A fragment of bone-earth did not dissolve or alter in appearance during seven days. Bright magnesium ribbon slowly became dull in the liquid acid, without visible evolution of gas ; after seven days' intermittent immersion it was still (with the exception of a thin film) in the metallic state. In a second experiment of three days' constant immersion, similar effects occurred ; the residue dissolved and floated in dilute sulphuric acid, with copious evolution of gas. A wire of magnesium and one of platinum immersed in the liquid acid, and connected with a sensitive galvanometer, evolved no perceptible electric current, and only a barely perceptible current after two days of constant immersion. Calcined magnesia in powder did not dis- solve or alter in appearance during four days' nearly constant immersion. Oxide of cerium (containing some oxide of didymium and lanthanum) remained undissolved and unchanged in colour during nine days ; the residue was insoluble in water. Metallic aluminium became dull in the gas, and quickly dissolved, with evolution of gas, when the liquid acid came into contact with it, and formed a colourless solution. A wire of aluminium and one of platinum, immersed ^th of an inch apart in the liquefied acid, and connected with a sensitive galvanometer, produced a steady deflectipn of 1 2g degrees, the aluminium being positive ; the deflection gradually increased to 1 7 degrees in one hour, and two layers of liquid formed, the lower one brown in colour, and the upper one nearly colourless. The conductivity of the liquid acid was probably increased by the metallic aluminium dissolved in it. Precipitated alumina did not visibly alter or dissolve during six days ; the residue deliquesced in damp air. Precipitated silica in powder did not dissolve or visibly alter during four days. Precipitated titanic acid in powder (pale flesh-colour) slightly dissolved in seven days. A fragment of fused tungstate of soda did not alter in bulk during ten days ; it had then acquired a superficial green colour. Molybdic acid in powder turned dark green, but remained undissolved at the end of nine days. Native sulphide of molybdenum remained undissolved and appa-r rently unchanged during two days. Molybdate of ammonia in powder became yellowish green in the gas ; it became grass-green in colour in the liquefied acid, but did not dissolve in four days. Sesquioxide of chro- mium in powder did not dissolve in six days, but became of a dull blackish- brown colour. A fragment of anhydrous yellow chromate of potash became 210 Mr. G. Gore on the Properties of [May 4, red before the gas liquefied, but did not dissolve or otherwise alter in the liquid acid. Sesquioxide of uranium became of a paler yellow colour in the gas, but did not dissolve in the liquid acid in six days ; the residue was entirely soluble in water. Precipitated black oxide of manganese in powder, and free from water, became quite white in the gas ; it remained white in the liquid acid without evolving visible bubbles of gas, and did not lessen in bulk in seven days. A crystal of permanganate of potash softened and swelled in the liquid acid, but did not dissolve in five days ; it remained of a dark colour ; the residue placed in distilled water produced no coloration. A crystal of metallic arsenic remained perfectly bright and unchanged in bulk during three days' immersion. Arsenious acid in powder quickly liquefied in the gas, and dissolved to a colourless solution in -the liquid acid. A crystal of arsenic acid softened before the gas 'liquefied, and dissolved quickly and freely in the liquid acid to a colourless solution. Bisulphide of arsenic in powder did not dissolve in six days, but became slightly less red and more yellow ; a slight yellowish-white sublimate oc- curred in the tube during the generation of the gas. Teriodide of arsenic in powder slightly dissolved to a purple-red liquid ; apparently only a trace of its iodine was extracted, as its bulk was not visibly less in three days. A crystal of bright antimony remained perfectly bright and unchanged after nine days' intermittent immersion. Precipitated teroxide of antimony became partly liquid before the gas liquefied ; it dissolved in the liquid acid quickly and rather freely, and made a colourless solution. A frag- ment of precipitated antimonic acid did not dissolve in six days. A frag- ment of black tersulphide of antimony evolved a film of yellowish- white sublimate, and lessened in bulk before the gas liquefied ; it decomposed and dissolved in the liquid acid in about a quarter of an hour, and formed a colourless solution which exhibited no further change during seven days. A fragment of bright metallic bismuth remained undissolved and un- changed in the liquid during three days. Bright zinc evolved no visible gas in the liquid acid, and was not per- ceptibly corroded in three days. Oxide of zinc slowly dissolved in seven days. Metallic cadmium evolved no gas in the liquid, and was not sensibly corroded in three days. Precipitated carbonate of cadmium evolved no visible gas in the liquid acid, and remained undissolved and unchanged in appearance during seven days. Yellow sulphide of cadmium evolved a trace of white sublimate before the gas liquefied ; in the liquid acid it became quite white, and remained undissolved in seven days ; on removal it was hard in texture and quite white throughout, and evolved no odour of sulphuretted hydrogen or separation of sulphur on treatment with strong nitric acid. Bright tin evolved no visible gas in the liquid acid ; after ten days' intermittent immersion it was converted, to some depth of its substance, into a bulky white solid with deep fissures. In a second expe- riment of three days' immersion, similar results occurred ; all the tin was corroded except a minute fibre in the centre, the white solid was imper- 1865.] Liquefied Hydrochloric Acid Gas. 211 fectly soluble in water, but instantly soluble in dilute hydrochloric acid. Binoxide of tin in powder did not dissolve in seven days ; the residue was white and insoluble in water. A crystal of protochloride of tin softened before the gas liquefied, and partly dissolved in the liquid acid in four days. Bright metallic thallium evolved no gas in the liquid acid, and was only superficially blackened without further corrosion after three days' immer- sion. Metallic lead did not evolve visible gas in the liquefied acid ; it became blackened at first, and in ten days was corroded deeply to a white substance. Red oxide of lead quickly became white in the liquid acid, but did not dissolve in seven days ; it was then quite hard, white through- out, and not readily soluble in water. Precipitated carbonate of lead evolved no visible gas in the liquid acid, and remained undissolved after three days' immersion ; the residue evolved no gas by contact with dilute hydro- chloric acid. Precipitated sulphide of lead in powder produced a faint film of white sublimate in the gas, and by a few hours' immersion in the liquid acid became wholly white ; it did not not dissolve during seven days, and was then quite white throughout, and not readily soluble in water. Yellow iodide of lead did not dissolve in seven days, but became of a pur- plish brick-brown colour and evolved a strong odour of free iodine ; it produced yellowish-brown stains upon paper. Yellow chromate of lead evolved at first (in the gaseous acid) a small quantity of deep-red vapour, which condensed as a red moisture near it on the tube ; the chromate became white] in the gas, and did not dissolve in the liquid acid in three days ; it was then a soft white solid, not freely soluble in water, and im- parted a faint greenish tint to water. A minute fragment of iron remained bright, and evolved no gas when the liquid acid came into contact with it ; after nine days of intermittent immersion it was only slightly tarnished, and on removal from the acid was found otherwise unaltered. A fragment of fused sulphide of iron pro- duced a faint film of whitish sublimate at first, but evolved no bubbles of gas on contact with the liquid acid ; it did not dissolve or alter in appear- ance. A second fragment constantly immersed during three days behaved similarly; it was as hard as before immersion, and evolved sulphuretted hydrogen freely in hot dilute sulphuric acid. A crystal of green vitriol became yellowish white and opaque in the liquid acid, but did not diminish in volume in six days; the residue was a soft opaque yellowish- white solid. Oxide of cobalt in powder exhibited no change or solution during three days ; on removal it was found to be very hard, of a light-brown colour, and dissolved in water, producing a pink solution with separation of black oxide. Peach-coloured carbonate of cobalt evolved no visible gas in the liquid acid ; it became greenish blue, but did not lessen in bulk in three days ; the residue became pink in the air, and dissolved almost completely in water, forming a pink liquid ; it also dissolved in dilute hydroclhoric acid without evolving bubbles of gas. Anhydrous chloride of nickel did not dis- solve in the liquid acid in six days. Metallic copper soon lost its brightness 212 Mr. G. Gore on the Properties of [May 4, in the gas ; it evolved no gas in the liquid acid, and was only slightly cor- roded after seven days. Black oxide of copper became of a lighter colour in the liquid acid, but did not lessen in bulk in seven days ; the residue was a greenish and yellowish white powder, which instantly turned black in water, forming a pale-blue solution, and left black oxide of copper. A crystal of blue vitriol became of a light brown colour in the liquid acid, but did not dissolve in six days ; on removal it was found to be a brown soft solid. Protoxide of mercury became white in the gas, and did not dissolve by constant immersion in the liquid acid iu four days ; the residue was a white solid, soluble in water. Vermilion in powder slowly changed in the liquid acid in three days to a pinkish-white solid, but did not dis- solve. Scarlet iodide of mercury in powder imparted a red colour to the liquid acid, but did not lessen in bulk or change in colour during three days ; the residue lost its red colour on the application of heat. A fragment of protochloride of mercury did not visibly alter in the liquid acid in four days. Metallic silver did not dissolve or become much corroded during seven days. Oxide of silver became white in the liquid acid in one day, but did not dissolve. Precipitated chloride of silver iu powder did not visibly alter or dissolve during sixteen days. Metallic pla- tinum was unaffected in the liquid acid. Oxalic acid was slightly dissolved in the liquid acid in three days with- out change of colour. Uric acid remained undissolved and unchanged during three days. Paraffin did not appear to be dissolved or affected in nine days. Gutta percha was quickly acted upon ; it imparted to the liquid acid, first a red, and ultimately a dark-brown colour ; it appeared also to dissolve in the acid to some extent, and on discharging the tubes was left behind as a tenacious coating upon the adjacent parts. Gun-cotton was unaffected in the liquid acid. Cotton was not visibly altered in two days. Solid extract of litmus dissolved slightly, forming a faintly purple blue or inky solution ; it became of a dark red colour and enlarged in bulk ; the residue formed a perfect solution in water ; the solution was red in colour. Remarks. — The foregoing experiments show that liquid hydrochloric acid has but a feeble solvent power for solid bodies in general. Out of 86 solids it dissolved only 12, and some of those only in a minute degree; of 5 metalloids it dissolved 1, viz. iodine; of 15 metals it dissolved only 1, viz. aluminium ; of 22 oxides it dissolved 5, viz. titanic acid, arsenious acid, arsenic acid, teroxide of antimony, and oxide of zinc ; of 9 carbonates i t dissolved none ; of 8 sulphides it dissolved 1, viz. tersulphide of anti- mony; of 7 chlorides it dissolved 2, viz. pentachloride of phosphorus and protochloride of tin ; and of 7 organic bodies it dissolved 2. The results show also that liquid hydrochloric acid in the anhydrous state manifests much less chemical action upon solid bodies than the same acid when mixed with water as under ordinary circumstances ; for instance, the difference of its action upon magnesium, zinc, cadmium, and even aluminium, under the two conditions, is very conspicuous. This may 1865.] Liquefied Hydrochloric Acid Gas. 213 arise in a great measure from its feeble solvent capacity — insoluble films forming upon the surface of the bodies immersed in it preventing its con- tinued contact and further action. This want of contact could hardly have been the case in the remarkable instance of caustic lime : here was a powerful and true acid (i. e. a hydrogen acid) and a powerful base; each in a nearly pure state ; both possessing under ordinary circumstances a very powerful chemical affinity for each other ; the one a liquid, and the other a porous solid ; brought into intimate contact by an enormous pressure forcing the liquid into the porous solid ; the solid base being very small in bulk, and the liquid acid largely in excess, probably fifty times the quantity necessary for its saturation ; and the action extended over a far greater period of time than would in the presence of water been at all ne- cessary : nevertheless no perceptible chemical action occurred ; the two remained totally uncombined. It must not be overlooked that the results are partly due to anhydrous hydrochloric acid in the liquid state, and partly to the same acid in the gaseous state, under great pressure, the one class of effects not being eliminated from the other in the present experiments ; it is probable that if the substances could have been submitted to the action of the liquid acid alone, the chemical effects would have been much smaller even than they were. For instance, the action upon potassium, sodium, and tin ap- peared to be due to the influence of the acid in the gaseous state, as no gas was perceptibly evolved by these metals in the liquid acid. In the cases of potassium and sodium (the latter in particular) it is perhaps pos- sible, though highly improbable, that the whole of the metal had been corroded before the liquid acid touched it ; but with tin this was certainly not the case, some metallic tin being left uncorroded at the end of the experiment. Oxides in general, with the exception of lime and certain others which do not readily combine with aqueous hydrochloric acid, were slowly converted in a greater or less degree into chlorides. Carbonates also, except that of lime, were in general converted in a greater or less degree into chlorides. Such carbonates as were decomposed evolved no visible bubbles of gas in the liquid acid : this may be explained on the supposition that they were previously completely decomposed by the (/aseous acid during the process of generation (this, however, was not the case with carbonate of soda), or that the liberated carbonic acid was in the liquid state and was dissolved by the liquid hydrochloric acid. In my former paper it was shown that liquid carbonic and hydrochloric acids generated and condensed together did not form two separate strata of liquid. Sulphides were in some cases converted into chlorides ; in other cases not so ; in nearly all cases a trace of whitish sublimate was produced in the (j aseous acid. The chlorate and nitrate of potash were both decomposed. I may here take the opportunity of stating that tubes charged with liquid carbonic acid in October 1860 suffered no leakage by February 1865. 214 Messrs. Simonds and Cobbold on the Production [May 4, II. " On the Production of the so-called 'Acute Cestode Tuberculosis' by the administration of the Proglottides of Tania mediocanel- lata." By JAMES BEART SIMONDS, Esq., Professor of Cattle- Pathology in the Royal Veterinary College, and T. SPENCER COBBOLD, M.D., F.R.S., F.L.S. Received April 13, 1865. Neither of us having exhausted certain funds placed at our disposal for scientific purposes (in the one case by the Royal Agricultural Society through the Governors of the Royal Veterinary College, and in the other by the British Association for the Advancement of Science), we have united the resources which severally remained to us, and have instituted a series of experiments in helminthology. These experiments, we are happy to state, have proved, for the most part, eminently successful; moreover, several of them not having been previously performed in this country, we have ventured to think that at least the firstfruits of our combined research in this particular relation might not unfitly be submitted to the notice of the Royal Society. The subject selected for the experiment which we now, proceed to relate, was a fine healthy female calf about a month old, living at the time on the milk of its dam. As we were unable to obtain possession of the dam, another cow was procured as a foster-mother, and the calf was placed with her in order that it might receive a proper supply of milk in the natural way. This plan was preferred to that of obtaining a weaned calf, as being better calculated to preserve the health and strength of the young animal. In the course of a few days the two animals became perfectly accustomed to each other, the calf taking nourishment as often as was requisite. On the 21st of December, 18G4, we administered to the calf eighty mature proglottides of the Teenia mediocanellata, mingled with a little warm milk in the form of a draught. The potion was taken readily, and the worm- joints probably entered the stomach in a perfect and unbroken condition. No alteration was made in the subsequent management of the animals, but a careful daily watch was kept upon the calf. ' For some time no indications were perceived of disturbed health ; but on the 6th of January, 1865 (the sixteenth day after the experiment), a careful observation showed that the animal, although lively (and taking its milk and likewise some hay with undiminished appetite), was nevertheless suffering from some persistent cause of irritation. It would often be nibbling at its legs and other parts of its body, and trying with its mouth and tongue to get at places which were beyond its ordinary reach. It would also fre- quently rub itself against the manger and sides of the loose box in which it was confined. Desisting from this, it would arch its spine and stretch out its hind limbs in an altogether unusual manner. It would also strain itself repeatedly, at such times voiding either urine or faeces, or occasion- ally both in small quantity. There was, however, no expression of suffer- 1865.] of Cystic Entozoa in the Calf. 215 ing in the countenance, no disturbance of the breathing or of the circula- tion, no injection of the visible mucous membranes, no alteration of the temperature of the body, no "staring" of the coat, nor rigors ; in short, no indication of anything seriously wrong. These symptoms continued throughout the next day with little variation ; on the third day they had nearly passed away, and by the fourth had entirely disappeared. On the 25th of January, 1865, just five weeks after the first worm- feeding, two hundred more of the mature proglottides of Tcenia media- canellata were administered ; but one hundred of these worm-segments had been previously immersed in a weak alcoholic solution, strong enough, it was feared, to destroy the vitality of their contained eggs. The other hundred proglottides were in beautiful condition, and for the most part ap- peared to be thoroughly mature. Again the calf took the feeding readily, and little or no force had to be employed in holding it during the adminis- tration. However, directly on being loosed, it was observed to show some symptoms of distress in the breathing, accompanied with trembling. The feeding took place at 3 P.M., and, as the night promised to be cold, it was placed with the cow in a closed and warm stable. On the following morning it was noticed that the tremors had somewhat abated, but the animal was evidently dispirited, and would every now and then grind its teeth as if in pain. Its appetite was much diminished. By the next day, however, all these diseased symptoms passed away, and the animal recovered its ordinary healthy aspect. On the 1st of February, the seventh day succeeding the second worm- feeding, there was a decided return of the nervous irritability ; but in a day or two these symptoms again declined. Nevertheless the animal was not quite right ; the coat began to lose its natural and glossy appearance, and there was an evident loss of flesh. Feb. 8th. — A marked change for the worse has taken place. The animal is dull and dispirited ; refuses all food excepting milk, and of this takes but little ; it arches the back frequently, and stretches the limbs in a peculiar manner ; the breathing and the pulse have increased, and at in- tervals slight tremors are observable, more particularly of the muscles of the neck and shoulders. Feb. 9th. — All the unhealthy symptoms are more marked. The pulse numbers 120, and the breathing 35 in the minute. The tremors are more continuous, and the condition of the animal is fast declining. Feb. 10th.— Still worse. The calf is so ill that we fear a fatal result. It takes little or no notice of the cow, and cannot be induced to suck. The eyes have a peculiar staring expression. Feb. llth. — The severity of the symptoms has somewhat abated this morning. The animal is rather more lively, and will now and then take a little milk. The breathing and pulse, however, remain rapid. The tre- mors, though still frequent, have diminished in intensity. Towards the after part of the day the improvement became more marked ; therefore, 216 Messrs. Simonds and Cobbold on the Production [May 4, instead of destroying the animal (as we had purposed in the event of its becoming much worse), we resolved to satisfy ourselves, by other means, as to whether the above symptoms were really due to parasite-invasion. Accordingly a small portion of the right sterno-maxillaris muscle was removed by operation, and this fragment of the flesh, although weighing only 22 grains, revealed the presence of three imperfectly developed cysticercus-vesicles. Each was about the size of a pin's head, but they displayed no trace of calcareous corpuscles, or of cephalic formation in their interior. On the assumption (afterwards, however, found to be erroneous) that all the muscles of the body might be similarly affected, and to the same extent, it was at the time calculated that the animal "entertained" some 30,000 of these artificially introduced "guests." Feb. 12th. — A further improvement has taken place, but the animal is still dispirited, the pulse and breathing continuing abnormally rapid. The eves are less staring. Feb. 13th. — Improvement continues ; breathing less rapid ; the tremors have disappeared. Feb. 15th. — Pulse diminishing ; breathing nearly normal ; appetite good. Feb. 22nd. — Convalescence perfectly re-established. Throughout the remainder of the month of February, and during the whole of March, the calf continued to maintain complete vigour, and, indeed, gained flesh so rapidly that at the beginning of April it might readily have been sold to a farmer, to a butcher, or to a cattle-dealer, as a thoroughly sound and thriving young beast. The time having, however, arrived for determining the result of the experiment, the calf was slaughtered on the 3rd of April, by division of the right carotid artery. The operation was performed by Mr. Pritchard, who also during the subsequent post-mortem examination rendered us essential service. As before, so after its death, all present remarked the particularly healthy aspect of the animal, there being no external indications by which the most practised professional eye could have discovered the existence of internal disease. But for our pre- vious trial we should ourselves have been doubtful of finding any entozoa within the flesh. Immediately after the first incision along the median line of the thorax, a solitary cysticercus came into view, many others successively displaying themselves as the integument was being raised and dissected from off the left side of the carcass. No person in this country having hitherto wit- nessed such a demonstration as now followed, we may perhaps be per- mitted to express the feeling of astonishment which all shared on thus beholding hundreds of larval cestode parasites in the flesh of an animal not usually considered capable of harbouring "measles" after the fashion of swine. Examined individually, the larvse were enclosed in oval sacs, whose trans- parency permitted us to see, at or near the centre of each vesicle, inter- nally, a minute white spot representing the so-called receptaculum capitis. .1865.] of Cystic Entozoa in the Calf. 217 On subsequent rupture of the cyst, a microscopic examination of the con- tained larva revealed the ordinary characters of the Cysticercus which pro- duces the Taenia mediocanellata. Speaking generally, it may he said that the connective tissue and cellular aponeuroses were very feebly invaded ; but in certain situa- tions, such as those occupied by the linea semicircularis and fascia lum- baris, several vesicles were closely associated ; moreover, as regards the muscles themselves, extensive parasitic invasion was prevalent only in the more superficial layers. It was likewise noticed, as obtains in the parallel case of Trichina, that the larvae were disposed in the longitudinal direction of the muscular fibres, being at the same time more numerously grouped towards the points of osseous insertion or of aponeurotic attachment. Not a few large vesicles had inflamed and suppurated, the cysts being occupied internally by a thick green-coloured deposit. Referring to the left side only, we noted that all the breast-muscles (pectoralis major, p. transversus, and p. anticus) were much infested, but scarcely so fully as the more superficial panniculus carnosus. In the latissimus dorsi and trapezius the cysts were very numerous, rather less so in the combined levator humeri and sterno-occipitalis, somewhat fewer in the rhomboideus brevis and rhomboideus longus, and exceedingly scanty in the superior part of the scalenus, the remainder of this last-named muscle being entirely free. The lateralis sterni contained none ; neither were any observed in the abdominal region of the serratus magnus, but several vesicles were lodged in the superficial cervical portion of this muscle. Not a few existed in the upper part of the complexus major and in the complexus minor, some also occurring in the longissimus dorsi ; yet none were observed in the spinalis dorsi, in the superficialis costalis, or in the diaphragm. Turning towards the neck-region, we found them abundant in the sterno-maxillaris, considerably less so in the splenius, only one in the hyoideus, several in the sterno-hyo-thyroideus, but none in the longus colli. All the other deep-seated muscles of this region, including the obliquus capitis superior and inferior, as well as the rectus capitis posticus major and minor, appeared free from any trace of the vesicles. On the other hand, all the superficial muscles of the face, such as the retractor anguli oris, orbicularis oris, and levator palpebrarum, gave abundant evi- dence of their presence, the vesicles being particularly numerous at the outer part of the masseter externus. In like manner their presence was only less strongly indicated in the muscles of the eyeball, such as the obliquus inferior, adductor and retractor oculi, also in the depressor oculi, one "measle " being placed between the tendon of this last-named muscle and the sclerotic coat. The ball of the eye itself contained no vesicles. A few were remarked in the substance of the genio-hyoideus and other muscles supplying the tongue ; but the lingual organ properly so called appeared to be entirely free. 218 Messrs. Simonds and Cobbold on the Production [May 4, As regards the anterior extremity, we found the Cysticerci very numerous in the teres externus and abductor humeralis, being scarcely less abundant in the spinatus anticus and posticus. They were likewise prevalent in the front part of the triceps extensor brachii, but altogether wanting behind and in the deeper portions of this muscle. A very few were remarked in the flexor brachii, whilst the subscapularis, teres internus, and coraco- humeralis failed to reveal any. They were very abundant in the flexor metacarpi externus, less so in the flexor metacarpi medius, and compara- tively scanty in the flexor metacarpi internus. The lower part of the combined flexor perforatus and perforans showed a few, several being like- wise present in the accessorius ulnaris. They were rather more abundant in the extensor metacarpi magnus, also in the extensor et adductor digi- torum, likewise in the extensor digiti externus, and scarcely less so in the extensor metacarpi obliquus ; yet none could be discovered either in the anconeus or in the humeralis externus. Over the haunch, and throughout the surface-flesh of the left hinder limb, the Cysticerci were particularly abundant, being numerous in the gluteus maximus, in the tensor vaginae femoris, and most especially in the large triceps abductor femoris. They were little less abundant in the vastus externus, and in those limited portions of the gastrocuemius ex- ternus and internus which come near the surface. A few vesicles were observed at the subcutaneous posterior section of the ischio-tibialis, also in the outer part of the biceps rotator tibialis and rectus femoris ; yet none were noticed either in the gluteus internus and gracilis, or in the vastus internus arid sartorius. In the flexor metatarsi and extensor pedis they were rather numerous, but, at the same time, comparatively scarce in the peroneus and flexor pedis perforans. Lastly, none were detected in either the psoas magnus or psoas parvus. With the exception of the heart, none of the viscera showed Cysticerci, the lungs, liver, kidneys, spleen, and thymus gland being absolutely free ; neither were any discovered in the brain. In short, it may be stated that the in- ternal organs of the body generally were perfectly healthy ; and even as regards the heart itself, the rather numerous vesicles found there displayed only a very incomplete development. At first they looked as if they might belong to a separate swarm-brood ; but a careful microscopic examination disproved this notion, and at the same time revealed some curious facts. In the heart none of the vesicles had attained one-third of the size of those pre- valent in the muscles, yet their age was doubtless the same ; for although none of those examined displayed a well-formed head with the charac- teristic and normal number of suckers, yet one vesicle was found to possess three suckers, another having two suckers, and a third only a single sucker. Most of the vesicles were entirely suckerless, whilst those which had them showed other indications of abnormality. The suckers themselves were not perfectly formed, in most cases, and there were commencing signs of cal- careous degeneration. In some instances, the entire contents of the vesicles 1865.] of Cystic Entozoa in the Calf. 219 appeared to have been absorbed, leaving only faint white spots to indicate the situations where the cysts once were. Such, at least, is our interpre- tation of the phenomena observed ; and, in this relation, we have only further to remark that the heart-cysts were not merely found at the surface of the organ, but were dispersed throughout its substance, one or two of the better- formed vesicles being lodged within the septum ventriculorum. On the present occasion we do not propose to offer any lengthened comment on the results of this experiment, but rather to let the facts speak for themselves ; nevertheless, to impart an aspect of completeness to our paper, we will offer one or two concluding remarks. So far as we are aware, only three experiments of this kind have been previously performed on the calf — namely, two by Leuckart, and one by Hosier. In two of these instances the experimental animal perished, whilst in the other case, as in our own, the creature barely escaped with its life. To our animal we administered a larger number of proglottides than had been given even in Mosler's case ; but, probably in consequence of the embryonic immaturity of the contents of many of the eggs, we did not get that fatal result which otherwise would inevitably have followed from a larger migration of the cestode-progeny. We believe that by far the greater proportion of the " measles" resulted from the second worm- feeding, in which case they would have come from the hundred proglottides not subjected to the action of alcohol. Although the characters presented by the earlier-developed morbid symptoms, as well as the time of their accession, induce us to attribute the diseased phenomena to the larvae set free by the first "feeding," yet it is clear, from the feebleness of the symptoms manifested, that only a very inconsiderable number of embryos can have entered on their wanderings. In the second " feeding," how- ever, the case is very different ; for here all the circumstances connected with the subsequent and marked disturbance of the animal's health point unequivocally to the development of that peculiar form of parasite-disease which Leuckart has designated as the "acute cestode tuberculosis." From the number of young vesicles present in the minute portion of muscle removed by operation from the living animal, we had (in the pages of the ' Lancet ') publicly announced our belief that we might ultimately find 30,000 Cysticerci developed in this calf; but as the larvae were subse- quently found to be almost entirely confined to the superficial muscular layers, it turned out that our calculation was considerably beyond the mark. Nevertheless from post-mortem data we estimate that there were between seven and eight thousand " measles " present, and one of us counted 130 vesicles at the surface of a single muscle. Lastly, it only remains for us to express our thanks to those gentlemen who supplied us with the necessary experimental material, namely, to Dr. Greenhow for the first tapeworm employed, and to Dr. Anderson and Mr. Brookhouse (Nottingham) for the second and third tapeworms, which were given together at the second administration. Dr. Greenhow's specimen VOL. xiv. s 220 Dr. Bence Jones on the Rate of Passage of [May 4, had the head perfect, both his and Dr. Anderson's examples being quite fresh. Mr. Brookhouse informed us that his specimen had been placed in " very weak spirit" ; but it is clear that the worm had been injuriously affected thereby, and the ova had lost their vitality. III. " On the Rate of Passage of Crystalloids into and out of the Vascular and Non-Vascular Textures of the Body." By HENRY BENCE JONES, A.M., M.D., F.R.S. Received April 26, 1865. (Abstract.) The paper is divided into five sections — 1st. On the method of analysis, and its delicacy. 2nd. Experiments on animals to which salts of lithium were given, upon the rate of their passage into the textures. 3rd. On the rate of the passage of lithium-salts out of the textures. 4th. Experiments on healthy persons, and on cases of cataract. 5th. On the presence of lithium in solid and liquid food. 1 . Three methods of analysis were followed, according as much or little lithium was present : first, simply touching the substance with a red-hot platinum-wire ; secondly, extracting the substance with water ; thirdly, incinerating the substance and treating it with sulphuric acid, and ex- hausting with absolute alcohol. ^ * — of a grain of chloride of lithium in distilled water could be detected, and „ * nnn to nn * „ of chloride .,,. , . . 6,000.000 2,000,000 of lithium in urine. 2. On Rate of Passage into the Textures through the Stomach. Even in a quarter of an hour three grains of chloride of lithium, given on an empty stomach, may diffuse into all the vascular textures, and into the cartilage of the hip-joint and the aqueous humour of the eye. In very young and very small guinea-pigs which have received the same quantity of lithium, in thirty or thirty-two minutes it may be found even in the lens ; but in an old pig in this time it will have got no further than the aqueous humour. If the stomach be empty, in an hour the lithium may be very evident in the outer part of the lens, and very faintly traceable in the inner part ; but if the stomach be full of food, the lithium does not in an hour reach the lens. Even in two hours and a half lithium may be more marked in the outer than in the inner part of the lens. In four hours the lithium may be in every part of the lens ; but less evidence of its presence will be obtained there than from the aqueous humour. In eight hours, even, the centre of the lens may show less than the outer part. In twenty-six hours the diffusion had taken place equally throughout every part of the lens. If the lithium is injected under the skin, in ten minutes it may be found in the crystalline lens, and even in four minutes, after the injection of three grains of chloride, the lithium may be in the bile, urine, and aqueous humour of the eye. 1865.] Crystalloids into and out of the Tissues. 221 3. On the Rate of Passage out of the Textures. After two grains of chloride of lithium, in six hours the lithium was more distinct in the outer than in the inner part of the lens. In twenty- four hours no difference in the different parts of the lens was detectable. In forty-eight hours no difference was observed. In ninety-six hours no lithium was detectable in the lens or cartilage of the hip-joint. The urine showed lithium very distinctly even in one drop. After one grain of chloride of lithium, in five hours and a half the lithium was more distinct in the outer than in the inner part of the lens. In twenty-four hours and a half there was no difference throughout the lens. In forty-eight hours the watery extract of the lens showed faint traces of lithium. In seventy-two hours and a half (three days) the alcoholic extract of the lens showed no lithium. The urine still showed lithium distinctly in one drop, and it continued to be found in the watery or alcoholic extract for twenty-one days. After half a grain of chloride of lithium, in three hours and fifty minutes traces of lithium could be found in the lens, and for thirty-seven or thirty- eight days traces of lithium could be found in the urine. After a quarter of a grain of chloride of lithium, in five hours and a quarter the aqueous humour showed lithium, and all the organs showed lithium, but none was in the lens. In another pig, in twenty-four hours all the organs showed less lithium, and none was found in the aqueous humour. After a quarter of a grain, in five hours and thirty-five minutes lithium was distinct in the aqueous humour, and very faintly traceable in the lens ; and after sixteen days the minutest traces of lithium could be detected in the lens, the liver, the kidney ; but no trace could be found in the blood. After three grains of chloride of lithium, in four hours lithium was in the hair of the belly, and for thirty-two days the urine showed lithium very distinctly. The thirty-third day after the lithium the lens was found to contain minute traces of lithium, and even after thirty-nine days the lithium was in the alcoholic extract of the urine. With three grains of chloride of lithium, a young pig in half an hour had lithium in the watery extract of the lens. In the same time an old pig had no lithium in the lens. With two grains, a young pig in six hours had lithium distinctly through- out the whole lens. An old pig in the same time had lithium in the outer part of the lens, but scarcely the minutest trace in the inner part of the lens. 4. Experiments on Healthy Persons and on Cases of Cataract. Ten grains of carbonate of lithia, taken three or four hours after food by a man, require from five to ten minutes to pass from the stomach to the urine, and this quantity of lithia will continue to produce traces of lithium in the urine for from six to seven days. s2 222 Dr. Bence Jones on the Rate of Passage, S$c. [May 4, Two grains of chloride or carbonate of lithia, taken shortly after food by a boy, gives no appearance in the urine until from ten to twenty minutes ; and this quantity continues to pass out for five, seven, or eight days. Experiments made by the ordinary mode of analysis showed that four grains of sulphate of protoxide of iron, taken by a man almost fasting, gave a trace in the urine in seven minutes. Seven grains gave distinct appearance in ten minutes ; and in ten minutes and a half one grain of iodide of potassium, taken by the same man fasting, appeared in the urine in twelve minutes. When no lithia had been taken, seven cataracts were examined most carefully, and only one showed an exceedingly feeble trace of lithium. When twenty grains of carbonate of lithia were taken twenty-five minutes before the operation, the lens showed no lithium. When twenty grains of carbonate of lithia were taken two hours and a half before the operation, the lens showed lithium in the watery cataract. When twenty grains of carbonate of lithia were taken between four and five hours before the operation, the lens showed lithium in each particle. When twenty grains of carbonate of lithia were taken seven hours before the operation, the lens showed lithium in each particle. When twenty grains of carbonate of lithia were taken seven days before the operation, the lens showed not the slightest trace of lithium. Twenty grains of carbonate of lithia, taken between six and thirty-six hours before death, showed the faintest indications of lithium in the lens. The cartilage showed lithium very distinctly. Ten grains of carbonate of lithia, taken five hours and a half before death, gave only faint traces of lithium in the lens, but the cartilage showed lithium very distinctly. 5. On the Presence of Lithium in Solid and Liquid Food. Potatoes showed traces of lithium once in five trials. Apples showed traces of lithium thrice in four trials. Carrots showed no lithium in two trials. Bread showed traces of lithium thrice in three trials. Cabbage „ „ twice in two trials. Tea „ ,, eight times in ten trials, Coffee ,, „ four times in five trials. Port wine „ „ six times in six trials. Sherry „ ,, six times in six trials. French wine „ „ four times in four trials. Rhine wine „ „ eight times in eight trials. Ale ,, ,, twice in three trials. Porter „ twice in three trials. 1865.] Mr. J. P. Harrison — Lunar Influence on Temperature. 223 Mutton, beef, and sheep's kidney showed no lithium : one kidney had a slight trace. CONCLUSIONS. 1. On the Rate of Passage of Solutions of Lithium into the Textures of Animals. Chloride of lithium taken into the stomach in quantities varying from one quarter of a grain to three grains, will pass into all the vascular parts of the body, and even into the non-vascular textures, in from one quarter of an hour to five hours and a half. 2. On the Rate of Passage out of the Textures of Animals. Chloride of lithium passes out by the skin as well as by the urine ; and thus the animals can redose themselves with chloride of lithium from the hair and feet, and prevent accurate observations. Hence probably chloride of lithium, in quantities varying from half a grain to three grains, will continue to pass out of the body for thirty-seven, thirty-eight, or thirty-nine days ; and even after thirty-three days, traces may be found in the lens ; but in three or four days no lithium may be detectable in the non-vascular textures. 3. In man, carbonate of lithia, when taken in five- or ten-grain doses, may appear in the urine in five to ten minutes if the stomach is empty, or twenty minutes if the stomach is full, and may continue to pass out for six, seven, or eight days. In two hours and a half, traces may be in the crystalline lens, and in five or seven hours it may be present in every particle of the lens and in the cartilages. In thirty-six hours it may be very evident in the cartilages. And in seven days not the slightest trace may be detectable in the crystalline lens. 4. Though in the solid and liquid food infinitesimal quantities of lithium may enter the body, usually no proof of their presence in the organs or secretions can be obtained. IV. "Lunar Influence on Temperature." By J. PARK HARRISON, Esq., M.A. Communicated by the Rev. R. MAIN, F.R.S. Received April 27, 1865. The tabulation of an unbroken series of thermometric observations for the several days of the lunation during fifty years having been completed up to November 1864, and an amount of lunar action detected which appears sufficient to set at rest the long vexed question of the moon's influence over our atmosphere, I venture to think that the time has arrived when it becomes a duty to lay the results of the investigation before the Royal Society. 224 Mr. J. P. Harrison — Lunar Influence on Temperature. [May 4, In 1856 the frequent recurrence of higher temperatures about the eighth or ninth day of the moon's age, led to an examination and compa- rison of the mean temperatures of the third day before, and the second day after first quarter of the moon, for a series of seven years at Chiswick, and sixteen years at Dublin. The results showed conclusively that the temperature of the second day after first quarter was higher than the temperature of the third day before that phase during the years in question. On extending the investigation to the remaining days of the lunation, the maximum was found to occur, at both stations, at the period when heat was first observed, and the minimum after full moon and last quarter. The long series of mean temperatures which had been determined by Mr. Glaisher for the British Meteorological Society from observations taken at Greenwich between 1814 and 1856, were next arranged in tables constructed for the purpose. These observations, though corrected by an arbitrary rule totally irrespective of the moon, and in a measure therefore eliminating influences that may have been exerted on the observed tempe- ratures, appeared on the whole the best, as they were also the most exten- sive printed series existing. The method pursued. — The Tables were constructed in the following manner : — The mean temperatures of the days on which the moon entered her four principal phases having been first inserted in columns arranged at equal distances, the mean temperatures of the first, second, and third days before and after each of the quarters were entered in the columns adjoining on either side ; and any remaining observations in octant columns midway between the quarters*. The deficiency occasionally occurring in an equal number of six observations between the quarters, was supplied by repeating the observation of mean temperature of the third day after, or third day before the quarters, the same observation in such cases being used for both those days. Thus an equal number of observations was secured for twenty-eight days out of 29 '5, at all the seasons of the year, a point of no little importance as regards the next process, viz., obtaining true means of the temperatures of the several days. This was done in the usual way, by adding together the observations of mean temperature in each column, and dividing the sums by the number of lunations the temperatures of which had been tabulated. The last operation consisted in laying down the mean line on scale-paper, and marking above or below it the mean temperatures belonging to the several columns on vertical lines, representing the several days of the luna- tion preceding or following the four quarters. The points thus marked * On an average, the number of observations in each of the octant columns equals half the number of observations in the other columns. Their means were not made use of iu forming the curves of temperature. 1865.] Mr. J, P. Harrison — Lunar Influence on Temperature. 225 on the scale-paper were united by straight lines, and thus formed what are usually termed " curves " of temperature. The results of the tabulation of the Greenwich observations. — The tabulation of the mean temperatures of the 520 lunations between 1814 and 1856, resulted in the complete confirmation of the phenomenon origi- nally observed ; that is to say, the maximum mean temperature showed itself, as before, in the first half of the lunation, and the minimum mean temperature in the second half of the lunation. The difference between the maximum and minimum temperatures for the 520 lunations was 1° Fahr. (see PI. V. fig. 1). In the autumn of 1860 M. Faye communicated the above results to the French Academy*. Additional Results in 1856-65. — The author has now the honour of laying before the Royal Society additional confirmatory evidence derived from a tabulation of mean temperatures at Greenwich for the eight years, or 99 lunations, which have elapsed since the year 1856f. Upon examining the lunar curve of temperature derived from these means (see PI. IV. fig. 2), the maximum mean temperature will be again found in the first half of the lunation, at the moon's first quarter, and the minimum mean temperature in the second half of the lunation. The difference is 3°'5 ; the maximum is 51°'7 ; and the minimum 480<2. The mean of the period is 49°'56. And on adding the sums of mean temperature of this period to the sums of the mean temperatures in the Table of 520 lunations, and divid^ ing the sums of the several columns by 619 (the number of lunations which occur in fifty years), the maximum is still found to occur at the first quarter, and the minimum shortly after last quarter. The difference be- ween the maximum and minimum mean temperatures is 1°'33. A curve of the mean temperatures for the 619 lunations will be found in PI. IV. fig. U. Explanation of the Phenomenon. — Although the recurrence of higher temperatures in the first half of the lunation, and more particularly at the moon's first quarter — as a meteorological fact — is not affected by the correctness or incorrectness of any explanation which may be given of the phenomenon, yet it will be well to state that a probable cause for the * Comptes Rendus, December 1860. t The Tables were laid before the Society, and are available for reference. t As regards the annual sums of temperature of the two days of maximum and minimum, the sums on the former day are higher than the sums on the latter day in 34 years out of 50. And the sum of the differences, in the years in which the mean temperature of the day before first quarter is higher than the mean temperature of the second day after last quarter is 783° 6, whilst the sum of the differences, in the years in which the mean temperature of the former day is lower, is 2200>0. For several years together, however, the day of maximum temperature presents itself, not on the clay before first quarter, but a day or two later (see PI. V. figs. 2, 3, and note oil fin.). 226 Mr. J. P. Harrison — Lunar Influence on Temperature. [May 4, apparent paradox of heat occurring at the moon's first quarter suggested itself in 1857*. It was evident that the effects noticed could not he due to any heat derived directly from the moon. Even if the experiments of Melloni and Bouvard — and, it may he added, the results obtained by Professor Piazzi Smythe on Teneriffe — had not established it as a fact that no serviceable heat, dark or luminous, reaches the lower strata of the earth's atmosphere at the period of full moon, the results of the tabulation of mean temperatures at various stations and for different periods of time show that, with some remarkable exceptions to be hereafter accounted for, cold displays itself on the average in the second half of the lunation, and a higher temperature at first quarter — at the very time when it may be supposed that the moon has parted with the whole of the heat she has received from the sun, and her crust opposite the earth has not been subjected to the solar rays for a sufficiently long period for lunar radiant heat to exercise any thermal action, either direct or indirect, on our atmosphere. This being so, the concurrent results of investigations undertaken by eminent physicists in this and other countries point to a maximum of cloud, rain, and vapour-bearing winds in the first half of the lunation, when the curves indicate heat f ; and a minimum of cloud and rain, with drier winds, in the second half of the lunation. It was not difficult then to connect the two phenomena — all gardeners being practically aware of the fact that heat is retained in the soil by the agency of cloud %, Professor Tyndall has shown by his elaborate experiments, that this is the case also with respect to the aqueous vapour of the atmosphere. Whether the dispersion of Cloud is due to the Radiant heat of the Moon. — As regards the degree of heat which is attained by the moon, Sir John Herschel estimates it as equal to the boiling-point of water ; and the same eminent person considers that the radiation of this heat would be sufficient to disperse cloud in the upper regions of the air. The estimate of the moon's heat appears to be that of our satellite at the period of opposition. But the maximum heat would not be attained until several days later ; for, the moon always turning the same face to the earth, her crust directly opposite to us does not attain its greatest heat until last quarter, at which time not only will it have received the sun's rays for twice the number of days during which that surface had been heated at the time of opposition, but the adjoining region also (eastward of it), itself recently illuminated and heated for fourteen, thirteen, and twelve times the length of our day of twenty -four hours, although the sun's * See Brit. Assoc. Reports, 1857, p. 248. t The number of clear and cloudy days at Greenwich, during the seven years (1841-47) that bihourly observations were made at that station, also corresponds with the hot and cold periods at the station. J See also Mr. Glaisher's paper on the subject in the Philosophical Transactions. 1865.] Mr. J. P. Harrison — Lunar Influence on Temperature. 2.27 rays have passed from it, still radiates the heat that has been absorbed, and which it may be presumed has penetrated to a depth (according to the speed with which the moon is travelling) commensurate with the time of its exposure to the sun. Again, as regards the date of the minimum temperature of the moon, doubtless the absence of all atmosphere must greatly augment the action of lunar radiation ; yet it is impossible to believe that the flood of heat poured iipon the moon day and night for so many days together, without intermission, can be speedily dissipated. It would be more consistent with the analogy of terrestrial meteorology that the state of cold in the moon should be prolonged beyond the renewal of the sun's radiation, and consequently no heat from her crust reach the limits of our atmosphere at first quarter. It would be strictly according to analogy, also, if the length of time which the moon's surface-crust takes to attain its maximum heat were found to be greater than that which it takes in falling to its minimum. Now there appears some reason to believe that this is the case ; and as the mean temperature of the year attains its maximum at Greenwich about the end of July (a considerable time after the summer solstice), and the day of minimum mean temperature occurs in the latter half of January (the intervals between the maximum and minimum, and the minimum and maximum, being as 5*5 to 6-5), so in the tables and curves of lunar tem- perature for forty-three and fifty years, a longer interval will be found between the day of maximum heat at the moon's first quarter and the day of minimum heat of the last quarter, than between the days of minimum and maximum. Assuming, then, that the earth and the moon absorb heat equally (due allowance being made for the alternate diurnal action of solar and terrestrial radiation in the case of the earth, and the prolonged bi- monthly alternation of solar and lunar radiation in the case of the moon), if we consider the portion of the curve between the days of maximum and minimum as representing the period during which the temperature of the moon is increasing, and the portion of the curve between the days of minimum and maximum as the period during which the temperature of the moon is decreasing, the same causes operating in the case of both planets, there would appear to be actual evidence of similar effects. Exceptions accounted for, — Whether, however, the moon clears the atmosphere by the agency of her radiant heat, or by thermo-electric currents, or by changing the direction of the winds (a phenomenon not un- frequently, perhaps, itself due to ascending currents caused by lunar radia- tion), the immediate cause of the phenomenon signalized by the curves would still seem to be the presence or absence of cloud and vapour in the higher regions of the air, and the exceptions to the rule of a period of cloud being on the average a period of heat would be owing to the varying positions of the sun, the moon, and the earth, or to the fact that the formation of 228 Mr. J. P. Harrison — Lunar Influence on Temperature. [May 4, cloud and vapour is due to the sun and the winds, and not in any wise, as it would appear, to the moon, or, lastly, to that system of compensation and alternation which seems to ohtain so frequently in atmospheric pheno- mena, and is so suggestive of mechanical force. The exceptions to the rule of a higher temperature occurring at the moon's first quarter, and lower temperatures after full moon, in any single year or group of lunations, are not more frequent than occur during the annual march of the seasons, and affect the position of the mean hottest and coldest day in the solar year. Several curves besides those referred to in the text are appended. Description of the Curves. — Plate IV. fig. 1. Curve of mean tempera- ture for 618 lunations (1814-65), from the Greenwich observations as corrected by Mr. Glaisher. Fig. 2. Curve of mean temperature for 99 lunations (1856-64), from the same source. Fig. 3. Curve of minimum temperature from the Greenwich observations for the same 99 lunations. Fig. 4. Curve of mean temperature for three years, or 37 lunations (1859-61), at Oxford, from the photographic curves of temperature taken at the Radcliffe Observatory. Fig. 5. Curve of mean temperature for the same three years as in fig. 4, from the ordinary means of the days at Greenwich, to compare with fig. 4. Plate V. fig. 1 . Curve * of mean temperature for 520 lunations (1814-56) at Greenwich. Fig. 2. Curve of mean temperature for the 86 lunations (1841-47) during which bihourly observations were taken at Greenwich. Fig. 3. Curve of mean temperature for 86 lunations (1837-43), from the Ordnance observations at Dublin. Fig. 4. Curve of mean temperature at Oust Sisolsk (Siberia), for 86 lunations (1837-43), to compare with fig. 3. (Mean of Russian observa- tions at 18h, 2h, and 10h.) Fig. 5. Curves of minimum temperature for one year (1859) at Green- wich and Utrecht. Note. — In 1848-56, the maximum occurred on the second day after first quarter, and a second maximum before last quarter. The minimum was found on the third day before first quarter, and the second minimum on the day before full moon. * This curve appeared in the British Association Reports for 1859. Plate IV. Lunar Curves of Prvo Pucy. Soo. Plate V. Lunar- Curves of MMUV 1858 (Mtn.T.) 1865.] Dr. Beale— Croonian Lecture. 229 May 11, 1865. Dr. WILLIAM ALLEN MILLER, Treasurer and Vice-President, in the Chair. "On the ultimate Nerve-fibres distributed to Muscle and some other Tissues, with observations upon the Structure and pro- bable Mode of Action of a Nervous Mechanism"*. Being the CROONIAN LECTURE for 1865, delivered by LIONEL S. BEALE, M.B., F.R.S., "Fellow of the Royal College of Phy- sicians, Professor of Physiology and of General and Morbid Anatomy in King's College, London ; Physician to King's Col- lege Hospital. INTRODUCTION. Of the movements occurring in the tissues of living beings, and of con- tractility. TlIE DISTRIBUTION OF NERVES TO INVOLUNTARY MUSCLE. Distribution of nerves to the muscular fibres of the frog's bladder. Distribution of nerves to the muscular fibres in the walls of arteries, veins, the intestine, ducts of glands, &c. — THE DISTRIBUTION OP NERVES TO STRIPED MUSCLE. Of the arrangement of the dark-bordered nerve-fibres distributed to voluntary muscle and other tissues; Of the division of dark-bordered nerve-fibres as they approach their distribution. Of the fine fibres running with the dark-bordered fibres. Of the distribution of the pale nucleated nerve-fibres to the elementary muscular fibres. The distribution of nerves to the muscles of articulata. Of the structure of the bodies termed nerve-tufts or -eminences (Nervenhugel) seen in connexion with certain muscular nerves. Of the arrangement of the nerve-fibres in other forms of striped muscle, as the branching muscular fibres of the tongue, the muscular fibres of the heart, and lymphatic hearts of the frog. Of the finest nerve-fibres which influence the muscle. THE ESSENTIAL STRUCTURE OP A NERVOUS MECHANISM CONSIDERED. Of the supposed terminations of the dark-bordered nerve-fibres, and of the probable existence of nerve-circuits. Of terminal plexuses and networks of fine nerve-fibres in the cornea, pericardium, fibrous tissue of the abdomen, and other parts. Fine nerve-fibres distributed to capillaries in the form of networks and plexuses. Arguments in favour of un- interrupted circuits, deduced from an examination of the trunks of nerves. Of the termination of nerves in papillae, and in special cutaneous nervous organs, such as the papillae concerned in touch and taste, and in the Pacinian corpuscles. Evi- dence, in favour of continuous nervous circuits, derived from the study of the deve- lopment of nerve-fibres distributed to muscle. Of the relation of the ultimate branches of the nerve-fibres to the tissue and to the germinal matter. Arguments in favour of uninterrupted circuits founded upon the structure and arrangement of ganglion-cells. General conclusions deduced from the above facts in favour of the existence in all cases of complete nervous circuits, and of the absence of any interrup- tion in the continuity of nerve-fibres. It seems to have been the desire of the founder of the lectureship which I have the honour to hold this year, that a lecture or discourse on the nature or property of local motion, accompanied by an experiment, should * This Lecture will be published shortly in a separate form, with all the drawings. The references made in the text to illustrations apply to the drawings and diagrams exhibited during the delivery of the Lecture. 230 Dr. Beale— Croonian Lecture. [May 11, be delivered annually to the Fellows of the Royal Society. It appears that the subject of muscular motion was selected by many of the earlier Croonian lecturers, and it has been generally considered that the Croonian Lecture should be confined to this department of local motion. Although this view was founded upon a misconception, it would indeed have been difficult to have selected a subject better adapted for frequent and repeated investigation and illustration than muscular motion. Notwithstanding more than a century has elapsed since the first Croonian Lecture was de- livered, the nature of muscular motion, and the mechanism taking part in its production, still remain to be discovered. In this as in every other de- partment of natural knowledge, it is to be noticed that the gradual pro- gress made by the unremitting labour of successive observers, so far from exhausting the fields of scientific inquiry, seems but to prepare the way for ever-increasing advance. By the excellent custom of appointing lecturers to deliver at certain intervals of time lectures upon the same department of natural knowledge, the actual progress achieved from time to time may be distinctly defined and duly registered, and new lines of inquiry suggested for future investi- gators in the same department. Although I have been led to choose for the subject of my lecture an anatomical question which seems extremely simple and of limited extent, I am compelled to leave many points but imperfectly studied ; and notwithstanding I have worked at this question earnestly for several years, my conclusions are in many respects still incomplete. It is remarkable how the positive determination of a simple question of fact may, as it were, recede as the investigation advances. However minute the detail, more and ever more detail seems required before all doubt can be removed from the mind of the student. I should not have ventured to ask the attention of the Fellows of the Royal Society to minute and, necessarily, in many respects incomplete anatomical detail, were it not that some broad questions of very general interest are involved in the inquiry I have undertaken ; and I think that I shall render what I have to say far less tedious and irksome than it would otherwise be, if I state, in the first instance, the questions proposed for dis- cussion, and the general nature of the inferences I have arrived at. It seems to me that we can scarcely hope to determine the manner in which the nervous system influences the muscular and other tissues, until we have ascertained how the ultimate branches of nerve-fibres are arranged, and have demonstrated by actual observation, or proved by other means, whether the nerves are disposed so as to form loops or plexuses, or whether they exhibit distinct ends, or terminate in special organs or by becoming continuous with other tissues. And it is impossible to separate from this inquiry the further and wider question, concerning the necessary structure and typical arrangement of a nervous apparatus. 1865.] Movements in Cells. 231 Our view regarding the nature of the force which produces such mar- vellous phenomena as those known to result from nervous action, will be materially influenced by the conclusion which we are led to accept regarding the fundamental arrangement of the nerve-cells and fibres, central and peripheral. If it could be shown that a nerve passes from its centre and ends by free terminations, or by becoming continuous with the muscular tissue, we should scarcely adopt the same general conclusion regarding the manner in which the nerve-centre influences the contractile tissue as we should if it were shown that the nerve merely passed amongst the muscular fibres without being necessarily even in actual contact with them, and returned towards, and eventually became connected with, the nerve-centre, without there being any solution of continuity in any part of the circuit. The investigations re- corded in this and other memoirs have led me to conclude th#t nerves invariably form circuits, and that there are in truth no ends at all. I believe that the nerve machinery is a complete circuit, and that the active phenomena are due rather to an alteration in the intensity of the current passing along the nerves, than to its sudden interruption and completion. In this Lecture I hope to be able to adduce facts which indicate the existence of fibres passing from and towards all central and peripheral nerve-cells. Before I proceed to the special subject of my Lecture, I must offer a few remarks upon contractility. Of late this term has been applied to move- ments occurring in living organisms which seem to me to be quite distinct in their essential nature from contractility. I cannot hold that the move- ments occurring in an amoeba or white blood-corpus.cle are of the same nature as those which occur in muscle, and I cannot, therefore, regard both classes of movements as manifestations of one property, contractility. Of THE MOVEMENTS OCCTTEKIXG IN CELLS AND IN THE TISSUES OF LlVING BEINGS, AND ON CONTKACTILITY. Vital movements. — The peculiar movements occurring in a mass of ger- minal matter are illustrated by the drawing now exhibited. Protrusions may occur at one or many points of the mass at the same time, and the whole mass may move in one direction like an amccba. Now it will scarcely be maintained by any one that the changes of form occurring in a mass of living matter are due to external agency. As far as can be ascertained by observation, the movement is primary, and depends upon the active forces inherent in the matter itself. This form of motion has never been explained or accounted for ; but as it ceases with the death of living matter, it is only reasonable to infer that it is intimately associated with those other phenomena which are peculiar to matter in the living state. It may therefore be termed vital motion, to distinguish it from every other kind of movement known. The rotation and other movements affecting the " pro- 232 Dr. Beale — Croonian Lecture. [May 11, toplasm" of certain vegetable cells, and the motion of masses of germinal matter in various tissues of man and animals must be included in this class of vital movements *. Ciliary action is, I think, a secondary phenomenon, due to changes going on within the cell, but probably very intimately connected with the currents flowing to and from the germinal or living matter, and the altered tension thus caused in the cell. Ciliary motion is not dependent upon nervous action, nor is it due to any disturbance in the surrounding medium. Ciliary motion cannot be regarded as a vital movement, although it is probably due to changes which are consequent upon vital phenomena. Cilia consist of " formed material." * No one will be more ready to receive and acknowledge that these movements and other phenomena characteristic of living matter are due to ordinary force than myself, BO soon as the correctness of such a doctrine shall have been proved, or, indeed, any advance towards this end shall have been made ; but as a working physiologist desiring to see, and promote to the utmost, real advance in this department of science, I consider it a duty to oppose as strongly as I can the practice pursued by some scientific authorities in the present day, and especially in this country, of reiterating the assertion that all the phenomena of living beings are to be accounted for by the action of ordi- nary force. Nothing can retard true progress more than exaggerated statements with re- ference to advance in any special direction. It is almost certain that the manifest anxiety to substitute for quiet proof intense and positive language, merely indicates bias, if not prejudice, in favour of views not supported by facts. I have already stated, not only that the doctrine does not rest upon any sound evidence whatever, but have drawn attention to the phenomena which occur in the simplest form of living matter, which never have been, and which I believe cannot be explained upon any known physical or chemical laws. Instead of these objections being answered, or the challenge to consider the matter in detail being accepted, we are told that the " tendency of modern science is towards this" apparently much-desired "end, and that although living matter cannot yet be prepared by man, the day is not far distant when its artificial production will be rendered possible," and so forth ! The fallacy underlying many of the modern doctrines is obscured, if not entirely concealed, by the very ingenious choice of words. For instance, when it is stated, with what appears to be learned precision, that force is "conditioned" by the ""molecular machinery" existing in the cell, few probably Vould be led to inquire what the molecular machinery was, and how the " conditioning " took place. Now it so happens that the changes in question occur without the existence of anything to which the term machinery can be properly applied. Instead of the living cell being like a machine, it is perhaps less like a machine than anything else that we have any knowledge of. The " living machine " is just a very minute mass of soft, colourless, transparent, semifluid matter, endowed with very wonderful properties or powers, in which matter is decomposed and its elements rearranged, while its forces are conditioned in a manner that cannot be effected by man with the aid of the most perfect machinery and elaborate apparatus his ingenuity has devised. Living matter is not a machine, nor does it act upon the prin- ciples of a machine, nor is force conditioned in it as it is in a machine, nor have the movements occurring in it been explained by physics, or the changes which take place in its composition by chemistry. The phenomena occurring in living matter are peculiar, differing from any other known phenomena ; and therefore, until we can explain them, they may be well distinguished by the term vital. Not the slightest step has yet been made towards the production of matter possessing the properties which distinguish living matter from matter in every other known state. 1865.] Movements of Granules within Cells. 233 In the immediate vicinity of ciliated cells are sometimes observed cells with open mouths, out of which mucus and various substances, formed or secreted in the interior of the cell, pass. In the formation of these pro- ducts, nutrient matter from the blood, after passing through the attached extremity of the cell, is probably absorbed by the living matter. At the same time the outermost portion of the latter becomes converted into the peculiar contents of the cell, and thus the formed matter which has been already produced becomes pushed towards the orifice. This is explained by the drawing; and I think that the movements of cilia are brought about by a somewhat similar series of changes, in which the germinal or living matter, usually termed " nucleus," plays the active and most important part. Movements of granules within cells. — The movement of insoluble par- ticles from one part of a cell to another, as occurs in the radiating pigment- cells of Batrachia, is probably due to alteration in the direction of the flow of fluid in the cells, from the cavity of the cell towards the tissues, or from the surrounding tissue into the cell. If the capillaries were fully dis- tended, fluid would permeate their walls and would pass into the cavity of the cells, in which case the insoluble particles would gradually become diffused and would pass into all parts of the cell ; while, on the other hand, if the capillaries were reduced in diameter, and the lateral pressure upon their walls reduced, there would be, as is well known, a tendency for the fluid in the surrounding tissue to flow towards the vessels and pass into their interior. In this case the quantity of fluid in the cells would be gradually reduced, and the insoluble particles would become aggregated together and would collect in those situations where there was most space, as in the central part of the cell, around the nucleus. Moreover, in the last case, the flow of fluid, which constantly sets towards the nucleus, would be instrumental in drawing the particles in this same direction, while if the cell contained a considerable proportion of fluid, the currents would pass between the particles without moving them. Evaporation, as it occurs after death, causes concentration of the insoluble particles towards the centre of the cells. On the other hand, the changes in the pigment-cells of the frog have been considered by Professor Lister to be due to vital actions, and he agrees with "Wittich and others that they are under the immediate control of the nervous system. Indirectly of course they are, but I do not think that any experiments have proved satisfactorily that the nerves exert any direct influence upon the movements of the particles in these cells. It is well known that the nerves govern the calibre of the vessels, and thus influence the amount of fluid in the surrounding tissue, and in this indirect manner they doubtless affect the movements of the particles in the cells. The reader will find a full account of Prof. Lister's experiments, and the argu- ments deduced from them, in his paper " On the Cutaneous Pigmentary System of the Frog," published in the Philosophical Transactions for 1858. Muscular movement is illustrated by the figures to which I now refer, 234 Dr. Beale — Croonian Lecture. [May 11, and which are intended to show the alterations in form supposed to take place in the ultimate particles of any contractile tissue — movements occurring in definite directions, which may be represented by lines at right angles to one another. These movements are quite distinct from those varied move- ments in all directions which affect matter in the germinal or living state. Contractile tissue is formed material, and contractility occurs in tissue which does not exhibit any of those properties or powers which distinguish living matter. It seems to me, therefore, that contractility is not a vital property; and I think that the term contractility should be restricted to movements which are remarkable for their constant repetition, and for the simplicity of their character. The changes which occur in the particles of a muscle during action might be spoken of as alternate shortening and lengthening. Experiment. The phenomena of contractility can be studied more satisfactorily in the muscles of the common maggot or larva of the blow-fly than in those of any other animal I am acquainted with. The movements, which are very beautiful, continue for ten minutes or a quarter of an hour after the muscles have been removed from the body of the recently killed animal; and I hope to be able to prepare a specimen which can be passed round in one of the portable microscopes and examined by the Fellows. [Preparation sent round.] In the winter I have seen the contractions continue for upwards of half an hour. But the most beautiful and instructive method of exa- mination is under the influence of polarized light, with a plate of selenite. In the microscope upon the table, the arrangement has been made; and when the ground is green, the waves of contraction which pass along each muscular fibre in various directions, are of a bright purple. In other parts of the field the complementary colours are reversed. There are few micro- scopic objects, that I am acquainted with, so beautiful as this. With the aid of very high powers, the actual change occurring in the contractile tissue as it passes from a state of relaxation to contraction, and from this to relaxa- tion again, may be studied, and for many minutes at a time*. Molecular movements. — The cause of the so-called molecular movements is probably complex, but quite independent upon any phenomena peculiar to living beings. The various movements occurring in the ultimate elementary parts or " cells " of living beings may be arranged as follows : — 1. Primary or vital movements. — Affecting matter in the living state only and occurring in every direction, as seen in the amoeba, white blood- corpuscle, mucus- and pus-corpuscle, young cells of epithelium, and in germinal matter generally. * The character of muscular movements is fully described in Mr. Bowman's well- 'known paper (Phil. Trans. 1841). See also Mr. Bowman's article, " Muscular Motion," in Todd's Cyclopaedia of Anatomy and Physiology. 1865.] Distribution of Nerves to Involuntary Muscle. 235 2. Secondary movements — the consequence of vital movements, or of other phenomena, affecting matter which is not in a living state : — a. Ciliary movements. — Probably due to alterations in the quantity of fluid within the cell, the changes in the proportion of fluid being brought about by the action of the living or germinal matter in the cell. b. Movements of solid particles suspended in fluid in cells, caused by currents in the fluid, as the pigmentary matter in the pigment- cells of the frog. — Due to the motion of the fluid as it passes into or out of the cell through its permeable wall, this movement being dependent upon changes taking place external to the cell. c. Molecular movements. — Which affect all insoluble particles, in a very minute state of division when suspended in a fluid not viscid. d. Muscular movements. — Due to a disturbance (electrical or otherwise) in the neighbourhood of a contractile tissue — that is, a structure so disposed that its constituent particles are susceptible of certain tem- porary alterations in position, which alterations take place in certain definite directions only. DISTRIBUTION OF NERVES TO INVOLUNTARY MUSCLE. Distribution of nerves to the muscular fibres and other tissues in the bladder of the frog. The demonstration of the ultimate arrangement of the most minute nerve-fibres is a matter of such great difficulty that the anatomist is com- pelled to search with the utmost care for a texture the natural structure of which happens to be favourable for his investigation. There are very few textures which possess so many advantages as the bladder of the frog. It is so thin and transparent, that it may be regarded as a natural dissec- tion and thinning-out of some of the most delicate tissues. The unstriped muscular fibres of this organ are extremely fine, and are slightly sepa- rated from one another. Nerve-fibres can often be seen in the intervals between the fibres. I have therefore selected this for illustrating the ultimate ramification of the nerve-fibres in involuntary muscle ; but I believe the statements which I shall make will be found to apply with equal force to every variety of this particular form of muscular tissue. With regard to the presence of nerve-fibres in involuntary muscle, I may remark that nerve-fibres have been demonstrated in so many different cases, that it is more in accordance with the positive knowledge already gained to infer that they exist in relation with every form of contractile tissue, even in cases in which we may still fail to demonstrate them, than to infer they are absent simply because we have failed to render them distinct*. * By contractile tissue I mean a tissue in which simple movements like shortening and lengthening alternate with one another, each movement heing a mere repetition of the first movement that occurred when ihc formation of the contractile tissue was complete. VOL. XIV. T 236 Dr. Beale— Croonian Lecture. [May 11, The bundles of dark-bordered fibres which may be traced to the pos- terior part of the frog's bladder divide and subdivide freely, spreading out in the form of a lax network, the fibres constituting which may be followed for some distance, and many may be traced to their ultimate distribution in the thin tissue of the bladder. Over a great part of the frog's bladder, however, no dark-bordered fibres or bundles of moderately coarse fibres can be detected ; yet the organ is in every part very freely supplied with nerves. Bundles of excessively fine fibres, first described by me*, may be traced running parallel with many of the small arteries, and may be seen to divide and subdivide into finer bundles, which at length form a plexiform net- work. Here and there is seen a plexus of very fine fibres, from which bundles of fine fibres diverge in different directions. That very many of these fine fibres come from the numerous ganglion-cells found in connexion with the nerve-trunks there is no doubt ; and it is equally certain that many also result from the division and subdivision of dark -bordered fibres. But whether the large dark-bordered fibres seen in the nerve-trunks pass directly to their distribution in the bladder, or in the first place become connected with ganglion- cells, it is difficult to decide with absolute certainty ; I have, however, traced several of the large fibres directly from the trunks to their distribution, but even in these instances I am not prepared to assert that no branches pass to the ganglion-cells. My impression is that sometimes this is the case, but that some of the fibres pass to their distribution without there being any such connexion with ganglion- cells ; and I think it probable that, of the fibres resulting from the division of a dark-bordered fibre derived from the cord, some may become connected with ganglion-cells, while others may pass to their distribution in the bladder without being connected with these cells. In the very thin membrane of which the walls of the frog's bladder are composed we may follow out the distribution of nerves — a to the muscular tissue, b to the surface of the mucous membrane, c to the vessels, and d to the connective tissue. In this drawing the general arrangement of the nerve network is repre- sented, from which fibres pass to supply all the tissues of the bladder. Upon the external surface of the lung of the frog muscular fibre-cells exist in small number, and to these a network of delicate nerve-fibres is dis- tributed. These muscular and nerve-fibres are, however, much more highly developed upon the newt's lung than upon that of the frog. But in this Lecture I restrict myself to the consideration of the distribution of nerves to the muscular fibre-cells, which is described in very few words and will be at once understood by reference to the diagram to which I now direct attention. The muscular fibre-cells of the bladder itself and of the small arteries * " On very fine Nerve-fibres in Fibrous Tissues, and on Trunks composed of very fine Fibres alone" (Archives of Medicine, vol. iv.). 1865.] Nerves in Involuntary Muscle. 237 are crossed sometimes in two or three places by very fine nerve-fibres ; and not unfrequently the nerve-fibre runs parallel with the muscular fibre-cell for some distance. These nerve-fibres are extremely fine, and require very high powers for their demonstration. They are certainly not connected in any way either with the nucleus or with the contractile tissue of the muscular fibre. They cross the fibre either obliquely or at right angles ; and oftentimes a nerve-fibre runs for some distance parallel with the muscular fibre. The influence, therefore, exerted by the nerve-fibre cannot depend upon any continuity of texture between it and the contractile tissue, but is doubtless due to the passage of a current through the nerve, which determines a temporary alter- ation in the relations to one another of the particles of which the contrac- tile tissue consists. Although I speak of the ultimate nerve-fibres as being arranged so as to form a network, it must not be supposed that this network is arranged on the principle of a capillary network. Every fibre of this network is com- pound ; so that perhaps the term " plexus " more truly describes the ar- rangement. " Plexiform network," I think, expresses the character of the arrangement still more exactly*. Some have said that my view accords with the old idea of looplike ter- minations of nerves ; and this is in the main true, but the course of one single fibre forming the loop is far more extensive than was supposed by the older observers, and the " looped fibres " divide and subdivide into finer fibres. This diagram is intended to represent a plan of the arrangement which is shown to exist in many tissues according to my observation. Although it be admitted that networks are formed, it might be said that from them fine fibres may branch off here and there, and terminate in ends within the space or area. The results of actual observation and a careful consideration of the various facts bearing upon the question are, however, strongly opposed to such a doctrine. Distribution of nerves to the muscular fibres in the walls of arteries, veins, the intestine, ducts of glands, fyc. So far as I can ascertain, all involuntary muscular fibre is freely supplied with nerve-fibres, and in all cases the nerves are arranged so as to form networks. In many instances ganglia are seen in connexion with the nerves ramifying amongst the muscular fibre-cells encircling the vessels. I have seen such upon the vessels of all the viscera and those of the palate * " In using the term network, I do not mean to imply that fine nerve-fibres unite with each other after the manner of capillaries, but merely that the bundles of fibres are arranged like networks. The fibres composing the bundles do not anastomose. In lace the appearance of a network of fibres is produced ; but every apparent thread is com- posed of several, each of which pursues a complicated course, and forms but a very small portion of the boundary of any one single space. In Plate XLI. fig. 5, a nervous network exists ; but each cord is compound, and composed of numerous fibres which never anastomose." — Note appended to a paper in the Phil. Trans. 1862. T2 238 Dr. Beale— Croonian Lecture. [May 11, of the frog : they are to be detected upon the iliac arteries in considerable number. The results of Mr. Lister's experiments render it probable that ganglia exist in connexion with the arteries of the limbs (Phil. Trans, pt. 2 for 1858, p. 620). In this figure a small ganglion in course of development upon one of the iliac arteries of the frog is represented ; and several fine branches of nerve- fibres can be followed amongst the muscular fibre-cells. I have seen very fine nerve-fibres beneath the circular muscular fibre-cells, apparently lying just external to the lining membrane of the artery, and composed of longitudinal fibjes with elongated nuclei — an observation which confirms a statement of Luschka's. I have not succeeded in satisfying myself that nerve-fibres are ever distributed to the lining membrane of an artery, al- though, from the appearances I have observed, I cannot assert that this is not the case. In the auricle of the heart and at the commencement of the venae cavae, very fine nerve-fibres are certainly distributed very near indeed to the internal surface, being separated from the blood only by a very thin layer of transparent tissue (connective tissue). The distribution of nerve-fibres to the coats of a small artery about the •g-jLjj-th of an inch in diameter is represented in this drawing. In all cases (and I have examined vessels in almost all the tissues of the frog), not only are nerve-fibres distributed in considerable number upon the external surface of the artery, ramifying in the connective tissue, but I have also followed the fibres amongst the circular fibres of the arterial coat. The nerves can be as readily followed in the external coat as in the fibrous tissues generally ; and the appearance of the finest nucleated nerve-fibres, already alluded to, enables one to distinguish them most positively from the fibres of the con- nective tissue in which they ramify. These nerves invariably form networks with wide meshes. I have de- monstrated such an arrangement over and over again. A similar dispo- sition may be seen in the auricle of the frog, in the coats of the venae cavae near their origin from the auricle, among the striped muscular fibres of the lymphatic hearts of the posterior extremities of the frog, and in other situations. Kolliker confesses that he has not succeeded in observing dis- tinct terminations to the nerves distributed to the vessels of muscles. He states that some arteries are completely destitute of nerves, and, apparently without having given much attention to the subject, says "hence it is evident that the walls of the arteries are not in such essential need of nerves as is usually supposed." It is easy to demonstrate nerves in considerable number on all the arteries of the frog, and in the case of certain vessels of man and the higher animals in which we have failed to demonstrate nerves, it is more reasonable to assume that they are there, although they have not been seen, than to infer their absence simply because we have failed to render them distinct. In the case of the umbilical arteries of the foetus and their subdivisions in the placenta, it is quite certain there are no true dark-bordered nerve-fibres, but we now know that the active part of a nerve 1865.] Nerves in Striped Muscle. 239 may consist of an exceedingly delicate, pale, and scarcely visible fibre, con- nected with a nucleus. Such delicate fibres and nuclei are to be demon- strated amongst the muscular fibres of these arteries, but in consequence of not having been able to trace them continuously for any great distance, I cannot assert that these are true nerves ; but no one has yet proved they are not nerves, or has demonstrated their real nature. The nerves which supply the small arterial branches in the voluntary muscles of the frog, come from the very same fibres which are distributed to the muscles. I have seen a dark-bordered fibre divide into two branches, one of which ramified upon an adjacent vessel, while the other was distri- buted to the elementary fibres of the muscle. In my paper " On the Struc- ture of the Papillae of the Frog's Tongue " these statements have been con- firmed ; and in the figure to which I now point, nerves distributed to arteries and to elementary muscular fibres of striped muscle are seen to be derived from the same trunk of dark-bordered nerve-fibres. DISTRIBUTION OF NERVES TO STRIPED MUSCLE. Of the arrangement of dark-bordered fibres distributed to voluntary muscle and other tissues. The plexiform arrangement of nerve-trunks and nerve-fibres is one which is very general, and was known even to the older anatomists. It can be demonstrated in many cases even by rough dissection. It exists not only in the case of nerves distributed to rmiscle, but, as far as is known, to every other tissue which receives a supply of nerves. Many of these networks are very beautiful ; and the arrangement is illustrated by these figures, which represent the bundles of dark-bordered nerve-fibres distributed re- spectively to the diaphragm of the white mouse, the mylohyoid of the green tree-frog, and the eyelid of the same animal. The fibres constituting the bundles never run perfectly parallel with one another, nor can a separate fibre usually be followed for any great distance. This arises from the fact that the fibres frequently cross one another, and many seem to pursue a spiral course. The spiral arrangement of nerve-fibres has been already described in former communications. At an early period of development one fibre may be seen coiled spirally round the other, as is well shown in this drawing*. The rule seems to be universal that fibres on one side of a trunk cross over and pursue their course on the opposite side. Those on the lower part of a trunk soon pass to the upper part, and vice versd. Instead of a nerve passing to its distribution by the shortest route, it invariably seems to pursue a very circuitous course. The course of the nerve-fibres in the optic commissure is not peculiar to this part of the nervous system, but a similar arrangement is to be met with in all nerves. When two trunks meet, as represented in this figure, fibres are found to pursue the several courses represented by the lines. * See also my paper " On the Structure of the so-called Apolar, Unipolar, and Bipolar Nerve-cells," Phil. Trans. 1863. 240 Dr. Beale — Croonian Lecture. [May 11, Division of the dark'bordered nerve-fibres as they approach their distri- bution. It is to be specially noted that the dark-bordered fibres very frequently divide, and, in consequence of the fibres being exceedingly thin at the points of division, which occur, for the most part, just where a bundle of fibres divides into two branches, they are seen only in very carefully prepared speci- mens. Although Wagner long ago showed that dark-bordered fibres un- derwent subdivision, the numerous subdivisions which I have demonstrated in all dark -bordered fibres near their peripheral distribution and also as they pass towards the nerve-centre, have not been generally observed. The number of fibres into which a single dark-bordered fibre divides is very great in a comparatively short course. The resulting subdivisions pursue very different directions, and can often be followed for a considerable distance as they run with other dark-bordered fibres. From this it follows that many different parts of a muscle at a distance from one another may be supplied with nerves which result from the subdivision of a single dark-bordered fibre.. The fibres resulting from the subdivision of the dark-bordered fibres are of less diameter than the parent trunks ; but the area of the section of two fibres would invariably be much greater than that of the parent trunk. For the most part the fibres divide dichotomously ; but sometimes a fibre is seen to divide into as many as three or four divisions, and in muscle five, six, or even more dark-bordered fibres have been seen to result from the division of one. The finer dark-bordered fibres often run in the same bundle with coarse dark-bordered fibres, the former being in fact much nearer to their ultimate destination than the latter. The dark-bordered fibres distributed to the muscles of the frog often divide into two very fine fibres, as repre- sented in several of these figures. These fibres may be traced onwards for some distance. They do not exhibit the dark-bordered character. They appear pale and granular, and connected with them at varying intervals are nuclei. These pale nucleated fibres in the frog are often less than the * of an inch in diameter. They are nevertheless compound, and consist of bundles of still finer fibres. These in fact, although much narrower, correspond to the pale, granular, but nucleated intermuscular nerves first described by me in the muscles of the mouse (Phil. Trans. 1860). The very fine compound fibres still continue to divide and subdivide, and assist to form plexuses and networks in precisely the same manner as the dark-bordered fibres, of which they are the continuation. It is quite cer- tain that these pale fibres are true nerve-fibres, for they are directly conti- nuous with the dark-bordered fibres. Instead of breaking up into one or more bundles of fine fibres, a dark-bordered fibre not unfrequently divides into a finer dark -bordered, and a bundle of fine fibres, as represented in this drawing from the frog's mesentery. 1865.] Fine Fibres with Dark-bordered Fibres. 241 Of the fine fibres running with the dark-bordered fibres. We find in the same nerve-trunk fine and coarse dark-bordered fibres, and we often observe exceedingly fine pale fibres running with dark- bordered fibres, the essential difference between these two classes of fibres in the same trunk being that the former fibre is nearer to its ultimate distribution than the latter ; but in some instances it is probable that the fine fibre is a branch of the sympathetic. The fine fibre runs in the same transparent matrix (sheath) with the dark-bordered fibre. In fact the idea of tubular membrane or sheath being an essential and separate anatomical constituent of every individual dark-bordered fibre must be given up. For, as I showed in 1860, several dark-bordered fibres and fine fibres might run together in the same sheath or matrix. The opinion that the fine fibres which I hold to be nerve-fibres running in the same sheath with the dark- bordered fibres, are not nerve-fibres at all, but modified connective tissue, is, however, still entertained by many observers. As I have before stated, their continuity with true dark-bordered fibres may often be seen, and the same fibre may in some instances be followed to its ultimate distribution. The different and incompatible views existing between continental observers and myself are in some measure due to this sheath question. The so-called sheath is not a "tube" or "membrane," or "tubular membrane," which con- tains the other constituents of the nerve-fibre ; nor is it a sheath which invests them, but it is simply a transparent matrix, in which nerve-fibres, coarse and fine, are imbedded. The so-called sheath is not formed as a special structure to invest the nerve-fibres, but it results from changes oc- curring in the nerve-fibres themselves. This " sheath " or " tubular mem- brane " of the so-called dark-bordered fibre precisely corresponds to the transparent connective tissue, in which the fine nerve-fibres are imbedded. It is a form of connective tissue, and in many situations where nerves existed at an earlier period, nothing but this so-called sheath remains. All the soluble fatty matters have disappeared, and this material, which is not readily absorbed, is left behind. Vessels may waste, and ducts and glands may waste, and leave behind them the same sort of transparent connective tissue. Moreover, as I have before stated, it is altogether a fallacy to suppose that near the peripheral distribution, every single branch of nerve- fibre is surrounded by its own separate sheath. The drawings of the so- called axis-cylinder near the terminal distribution of the nerves also seem to me to be diagrammatic, founded rather upon a theoretical idea of the consti- tution of the nerve-fibre than upon the results of actual observation. Many of the pale fibres accompanying the dark-bordered fibres are doubtless sympathetic fibres, for it has been shown that there are fine fibres springing from ganglion- cells which retain the same character from their origin to their distribution (see p. 236). Not only has the nervous nature of the fine fibres above described been proved by tracing them from their connexion with ganglion-cells, but a dark-bordered fibre has often been observed to be drawn out so as to form a line as fine as these fine 242 Dr. Bealc — Croonian Lecture. [May 11, fibres. Indeed the observer often fails to trace an individual dark-bordered fibre for any great distance in consequence of its becoming exceedingly fine at the point where it crosses, or is crossed by other dark-bordered fibres. Not only so, but where a bundle of comparatively wide dark-bordered fibres passes through a small aperture, as for example in a bone, the fibres appear, as it were, drawn out to exceedingly thin threads, as represented in this figure. And it may be fairly argued that since a wide dark -bordered fibre may be reduced in certain parts of its course to a fine cord not more than the soocx^h °f an inc^ m Diameter, without its integrity or conducting-powor being interfered with, there is nothing unreasonable in concluding that fine fibres of the same diameter are efficient conductors of the nerve-current, although their length may be considerable. And I have shown that iu many of the tissues of the frog (bladder, connective tissue, auricle, &c.), the finest branches of the nerves at their distribution are invariably less than the aoiootb °f an inch in diameter. Is it then probable that the nerves distributed to the elementary fibres of the voluntary muscles of the limbs should form the single exception to this very general arrangement, and that the peripheral nerves of muscle should exhibit the dark-bordered character up to, or to within, a very short distance of their ultimate distribution or termination, as is maintained by many German anatomists. Of the distribution of the pale nucleated nerve-fibres to the elementary muscular fibres. Few anatomical questions have received of late years a larger share of at- tention than the ultimate arrangement of nerve-fibres in voluntary muscle. It is a matter of regret to me that although I have studied the question in many ways during the last five years, my conclusions do not accord with those of any other observer. And I must admit that although the German writers differ from one another on not unimportant points, they, nevertheless, agree in this, that the nerves form ends, pass into end-organs, or exhibit terminal extremities of some kind ; while on the other hand my observations have led me to conclude not only that nerves never terminate in ends in vo- tary muscle, but that there are no terminal extremities or ends in any nervous organ whatever. With regard to the ultimate arrangement of nerves in muscle, the con- clusions of Kolliker accord more nearly with my own than those of any other observer. (Compare Kolliker' s statements iu his Croonian Lecture delivered in 1862, with the results stated in my paper, published in the Phil. Trans, for 1860.) Kolliker agrees with me in the opinion that the nerves lie upon the external surface of the sarcolemma ; but what he regards as ends or natural terminations, I believe to be mere breaks or interruptions in fibres which in their natural state were prolonged continuously. And there is this further broad difference between foreign observers and myself, that while they consider that each elementary muscular fibre is very 1865.] Distribution of Nerves to Striped Muscle. 243 sparingly supplied with nerves — a very long fibre receiving nervous supply at one single point only — I have been led to conclude that every muscular fibre is crossed by very delicate nerve-fibres, frequently, and at short intervals, the intervals varying much in different cases, but, I believe, never being of greater extent than the intervals between the capillary vessels. My friend Kiihne, of Berlin, has probably published more papers upon this vexed question than any other observer. He maintains that the nerve always passes through the sarcolemma and comes into direct contact with the contractile tissue*, or ends in protoplasmic matter which is in continuity with the muscle. He has, however, from time to time been led to modify his view very materially, as these figures, copied from his various memoirs published between the years 1862 and 1864, will testify. In his memoir published in 1862, he described minutely the structure of some very peculiar organs, which he stated had been demonstrated by him in connexion with the pale terminal intramuscular branches of the nerve-fibres. In more recent memoirs he seems to have abandoned the idea of the existence of those very peculiar bodies which he termed " Nerven-Endkuospen," and with reason, since no other observer professes to have seen objects at all resembling those figured by Kiihne. I should, however, state that the observations of Kiihne have in the main been supported by Engelmann and some other observers. In this Lecture I am unable to give even a brief account of the different views now entertained by the numerous observers who have studied this question ; but in these drawings some of the most important are represented. A record of the opinions entertained by various writers will be found in Kiihne's memoir, published in Virchow's 'Archiv,' vol. xxx. 1864; and I append the titles of some of the most important communications which have appeared since the publication of my first memoir : — Kiihne. Note sur un nouvel organe du systeme nerveux. — Comptes Rendus, Feb. 1861. Kiihne. Ueber die peripherischen Endorgane der motorischen Nerven. — Leipzig, 1862. Theodor Margo. Ueber die Endigung der Nerven in der quergestreiften Muskelsubstanz.— Pest, 1862. Kolliker. Untersuchungen iiber die letzten Endigungen der Nerven. — 1862. Rouget. Note sur la terminaison des nerfs moteurs dans les muscles chez les reptiles, les oiseaux et les mammiferes. — Comptes Rendus, Sept. 20th, 1862 ; also Brown Se'quard's Journal, 1862. Naunyn. Ueber die angeblichen peripherischen Endorgane der moto- rischen Nervenfasern. — In Reichert und Du Bois Reymond's Archiv, 1862, p. 481. * This view was first advanced by Kiihne in 1859 (" Untersuchungen iiber BCTVC- gungen und Veriinderungen der contractilen Substanzen," Reichert und Du Bois Rev- mond's Archiv, 1860). 244 Dr. Beale — Croonian Lecture. [May 11, L. Beale. Further observations on the Distribution of Nerves to the Elementary Fibres of Striped Muscle.— Phil. Trans., June 1862. Krause. Ueber die Endigung der Muskelnerven. — Henle und Pfeufer's Zeitschrift, 1863, p. 136. Th. W. Engelmann. Ueber die Endigungen der motorischen Nerven in den quergestreiften Muskeln der Wirbelthiere. — Centralblatt f. d. Medic. Wissensch. 1863. L. Beale. On the Anatomy of Nerve-fibres and Cells, and on the ulti- mate Distribution of Nerve-fibres. — Quarterly Journ. of Mic. Science, April 1863. L. Beale. Further observations in favour of the view that Nerve-fibres never end in Voluntary Muscles. — Proceedings of the Royal Society, June 5, 1863. L. Beale. Remarks on the recent observations of Kiihne and Kolliker upon the termination of the Nerves in Voluntary Muscle. — Archives of Me- dicine, vol. iii. p. 25. Th. Wilhelm Engelmann. Untersuchungen iiber den Zusammenhang von Nerv- und Muskelfaser. — Leipzig, 1863. Kiihne. Ueber die Endigung der Nerven in den Muskeln. — Virchow's Archiv, Band 27. Kiihne. Die Muskelspindeln. — Virchow's Archiv, Band 28. Kiihne. Der Zusammenhang von Nerv- und Muskelfaser. — Virchow's Archiv, Band 29. L. Beale. An Anatomical Controversy. The distribution of Nerves to Voluntary Muscle. Do nerves terminate in free ends, or do they invariably form circuits and never end ? — Archives of Medicine, vol. iv. 1865. Pub- lished separately : Churchill, London ; Denicke, Leipzic. L. Beale. On the Structure and Formation of the Sarcolemma of Striped Muscle, and of the exact relation of the nerves, vessels, and air- tubes (in the case of insects) to the contractile tissue of Muscle. — Trans. Mic. Society, 1864. Rouget. Sur la terminaison des nerfs moteurs chez les Crustacea et les Insectes. — Comptes Rendus, Nov. 21, 1864. As the observations of Kolliker, Kiihne, and other observers in Ger- many, who followed me, were made upon the breast-muscle of the frog, while my first inquiries were instituted upon the muscles of the white mouse, I subjected this particular muscle of the frog to the same process of investigation which I had previously adopted in my researches in 1858-59, which were published in I860. The results of these investigations will be understood by reference to these drawings, most of which were printed in my paper published in the Philosophical Transactions for 1862; and as explanations are appended to these figures, it is unnecessary to describe them more minutely here. Although the results of this further inquiry (published in 1862) were favourable to the view I had advanced, they were deficient in this most 1865.] Distribution of Nerves to Striped Muscle. 245 important point, viz. that the supposed network (as seen in this scheme) had not heen conclusively demonstrated over the frog's muscular fibres gene- rally. Near the point where the dark-bordered fibre divided to form pale fibres, a network was demonstated as is here shown, but it could not in many instances be traced for any great distance from this point. The following points, however, seem to me to have been established in this memoir : — 1. That the nerve-fibres, as I had already stated and as was confirmed by Kolliker, were outside the sarcolemma. 2. That the fibres might be followed for a greater distance from the dark-bordered fibre than they had been traced before, if the specimens were prepared according to the new method of investigation which I described. 3. The fine pale fibres were proved to be composed of several finer fibres, which resulted from the division of the dark-bordered fibre, and the pale fibres in the sheath of the nerve, which were also demonstrated for the first time. 4. Contrary to the statements of Continental observers, it was proved that the elementary muscular fibres of the frog were crossed at numerous points by nerve-fibres, and that the nervous supply to each elementary mus- cular fibre was much more free and uniform than was supposed. This fact may be demonstrated more especially in the thin muscles of the eye and in the mylohyoid of the frog. Not satisfied with these results, I examined numerous other muscles of the frog and other animals, in the hope of being able to demonstrate the finest nerve-fibres in every part of their course over the sarcolemma, but was not able to obtain any muscle in the common frog sufficiently thin to trace the finest branches over a very considerable extent of surface. In the mylohyoid of the Hyla, however, I found a muscle eminently adapted for this investigation; and on June 5th, 1863, I presented a paper (pub- lished in the ' Proceedings') to the Royal Society upon the arrangement of the nerves in this beautiful muscle. I have prepared many specimens in which the nerve can be followed from one undoubted nerve-trunk to another, dividing and subdividing in its course, so as to form with other nerves a lax network of compound nucleated fibres, which compound fibres are often less than the g^^ of an inch in diameter. The arrangement will be understood by reference to this drawing, which explains itself. I believe that no other explanation of the appearances observed in these specimens, than the one I have adopted, can be offered. In some of the muscles at the root of the tongue, the same arrangement has been demonstrated most distinctly. More recently I have again studied the elementary muscular fibres from the breast-muscle of the frog, and have succeeded, in many cases, in tracing the fine granular nucleated fibres for a considerable distance. Near the margin of the muscle, I have recently succeeded in following a very fine fibre, resulting from the subdivision of a dark-bordered fibre, into fibres prolonged from what appear to be connective-tissue-corpuscles. The nuclei 246 Dr. Beale — Croonian Lecture. [May 11, of the network of fine nerve-fibres have often been mistaken for the con- nective-tissue-corpuscles beneath and, in some cases, amongst which they lie ; and as old nerve-fibres, as well as other structures, degenerate and leave behind them what is called " connective tissue," a mistake is easily made unless the preparation be very clear*. In this drawing some very fine nerve-fibres, distributed to a portion of muscle at some distance from a dark-bordered fibre, are represented. The distribution of nerves to the muscles of Articulata. The highly elaborate and rapid movements of insects would lead to the inference that in them the distribution of nerves to the muscles must be very free. The textures are, however, so very elaborate, and their structure so minute, that the difficulty of demonstration must needs be greatly increased. Kiihne's memoir, published in the year 1860, related to the dis- tribution of nerves to the muscles of Hydrophilus piceus. He represented the nerve as perforating the sarcolemma, and being distributed almost in a brush-like manner to the contractile tissue. Subsequently he thought the nerve was connected with the line of muscular nuclei ; but it was obvious that these were muscular, not nervous nuclei at all, and this view was abandoned. Some other observers have fallen into the same error. Al- though I have examined the muscles of many insects, and especially those of the Hydrophilus, I have been unable to confirm the observations made by some Continental observers. For illustrating the distribution of nerves to the muscles of insects, I will select the common maggot, the larva of the blowfly. This insect can be obtained in all countries at almost all seasons of the year. By reference to these drawings it will be seen that my conclusions accord in the most important particulars with those arrived at in my earlier investi- gations. The drawing-out of the sarcolemma into a sort of eminence at the point where the nerve commences to ramify over it, is well seen in these two figures. This has been mistaken for a special organ by Kiihne (Nerven- hiigel) ; and it has been inferred that the nerve perforated the sarcolemma at this point. In his paper in the ' Comptes Rendus' for November 21, 1864, M. Rouget in part confirms my statements regarding the structure of Kiihne's ' Doyere'schen Nevenhiigel,' and states that, at the Nervenhiigel, the nerve- fibre divides into two fine fibres, which may be traced for some distance, and then terminate. " Leur extremite terminale est le'gcrement effilee ; elle ne presente ni plaques, ni noyaux, ni substance finement granuleuse." The structure of these so-called Nervenhiigel in insect-muscles was described and figured by me in a paper, accompanied by several drawings, read to the Microscopical Society on June 1, 1864, and published in the 'Transactions ' on October 1, 1864. Although M. Rouget agrees with me * This part of the question is considered in ray paper published in the Philosophical Transactions for 1864, page 565. 1865.] Of the Nerve-tufts, Nervenhugel, $c. 247 as respects the nature of the Nervenhugel, we are at variance upon the further course and mode of termination of the nerve-fibre, M. Rouget maintaining that it penetrates beneath the sarcolemma and there terminates in a very fine fibre, in contact with a very limited portion of the contractile tissue, while I have been able to trace the nerve for a long distance beyond the point at which he makes it end, and I have seen it dividing into very fine fibres, which form an extended network upon the sarcolemma, as repre- sented in this drawing, to which I beg to direct special attention. M. Rouget' s researches lead him to conclude that the arrangement of the nerves in the muscles of Articulata is totally distinct from that met with in Verte- brata. " II result de ces faits qu'il n'y a pas d'identite entre les divers modes de terminaison des fibres nerveuses motrices chez les vertebres et les articules." On the other hand, my observations lead me to the conclusion that the arrangement is in its essential points the same in all classes of animals. In no case are there nerve-ends, but always plexuses or networks, which are never in structural continuity with the contractile tissue of the muscle. I have particularly studied the arrangement and distribution of the nerves in the leech. The same facts noticed in p. 258 on the branching of nerve-fibres, are observed in the nerves of this animal ; and I have been able to obtain many specimens of nerves which could hardly be distinguished from some of the finest dark-bordered fibres of the higher animals. Some of the muscular fibres of this animal are very thin, and are separated from one another by considerable intervals, in which the ramification of exceed- ingly delicate nerve-fibres can be readily detected, and the nerve-fibres can be followed to their connexion with ganglion-cells. I have made many specimens of the muscles of the leech, and taken several drawings to illus- trate these points, but I regret that I am unable to have these copied for this memoir. Of the structure of the bodies termed nerve-tufts, nerve-eminences, and Nervenhugel, seen in connexion with certain muscular nerves. I propose now to consider the structure of the peculiar bodies in con- nexion with the nervesdistributed to the muscles of certain animals, described by Kiihne, Rouget, Krause, and others. These differ from the bodies first studied by Kolliker in the breast-muscle of the frog, which are referred to in p. 261. I have never been able to demonstrate such bodies as I am about to describe in the muscles of animals generally, although they are ex- ceedingly distinct in the muscles of lizards, as shown by Rouget. I have demonstrated many in the cutaneous muscles of the neck, and in the muscles of the tongue of the chameleon, and shall carefully consider the structure of these. In the first place, I would remark that these bodies are external to the sarcolemma, as may be proved by examination of the specimens. The course of the nerves to and from these bodies almost renders it impossible 218 Dr.Beale — Croonian Lecture. [May 11, that they could be beneath the sarcolemma, while in many cases the outline of the sarcolemma can be followed underneath them. Secondly, it appears probable that they are a reduplication and expansion of continuous fibres, rather than terminal organs formed upon the extremities of the nerve-fibres ; nor would it seem that these organs are essential to the action of nerves upon muscle, since they are only to be demonstrated in the muscles of cer- tain animals. Moreover, as many different forms of these nerve-organs are to be seen in a small piece of muscle, exhibiting different degrees of com- plexity, we may perhaps by studying them attentively be able to draw a true inference as to their real structure and the mode of their formation. Kuhne's idea of the structure of these bodies is represented in this diagram, which has been copied from his last paper. The interpretation of the appearances here given is totally different from that which I have been led to offer. In my specimens the nerve-fibres entering into the formation of these tufts are seen to divide and subdivide into several branches, which are folded, as it were, upon one another. The fibre in many instances does not consist of the axis-cylinder only, but the white substance may also be detected in connexion with some of the fibres. The nuclei seem to be con- nected with the finer branches of the nerve-fibres. In fact the organ seems to consist partly of broad fibres, partly of fine fibres formed by the branch- ing, spreading out, and coiling of the fibres resulting from the subdivision of the original nerve-fibres which enter into the formation of the tuft. Moreover I have succeeded in demonstrating that, from various points of the oval coil, branches pass off and run on the surface of the sarcolemma, pro- bably passing on to other nerve-bundles. These fine fibres, which are represented in my drawings, have not been delineated, as far as I am aware, by any previous observer who has examined these bodies. In connexion with every nerve-tuft there seem to be entering and emerging fibres ; and in the majority of instances, fine fibres may be traced from the tuft in several different directions. When the nerve-tuft is formed, as it were, upon the trunk of the fibre, the entering fibres are more numerous and larger than the emerging fibres. This is probably to be explained by the circumstance that some fibres pass away from each tuft upon the surface of the muscle, and thus establish communications with nerve-fibres which approach the elementary mus- cular fibre at other points. This drawing explains how, as the muscular fibre grows, the bundles marked a and b become separated further and further from one another, and the fine communicating fibres connecting them necessarily become so very much drawn out that they are too delicate to be seen upon the surface of the sarcolemma. And now it must be obvious that these bodies precisely correspond to the bendings and division of the fine dark-bordered fibres at the point where they come into contact with the surface of the sarcolemma, in the breast- and other muscles of the frog. At this point there is always a twisting of fibres with free branching, and the formation of a number of exceedingly 1865.] Distribution of Nerves to Striped Muscle. 249 delicate nerve-fibres, the nuclei or masses of germinal matter being very close together, so that a considerable number are to be observed within a com- paratively small space. Here a complex network of fibres, the meshes of which are very small, is found. But this plexus or network is not terminal, nor does it result from the branching of a single fibre, as has been repre- sented. Many fibres enter into its formation ; and from various parts of it long fine fibres pass off to be distributed upon the surface of the sarcolemma. This is explained in these figures from the frog, from the white mouse, and in this one from the maggot. It seems most probable that at the situation of these coils the contraction of the muscular fibre would commence, and that, from the nerve-current tra- versing several fibres collected over a comparatively small portion of muscle, the contraction at these points would be most intense, while it is probable that the contractions commencing at these points would extend, as it were, from them along the fibre in opposite directions. I consider these nerve- tufts therefore simply as collections of nerve-fibres, differing only from the ordinary arrangement before described, somewhat in the same manner as the compressed nerve-network in a highly sensitive papilla differs from the lax expanded nerve-network in the almost insensitive connective tissue. Of the arrangement of the nerve-fibres in other forms of striped muscle, as the branching fibres of the tongue, the muscular fibres of the heart, and lymphatic hearts of the frog. To certain forms of striped muscle in which no distinct membranous tube of sarcolemma can be demonstrated, nerves are freely distributed ; but all attempts to demonstrate end-organs or terminal extremities in such tex- tures have hitherto failed. In the heart the existence of delicate nerve- fibres arranged to form networks is distinct ; and perhaps the most favour- able locality for demonstrating these fibres is the auricle of the frog's heart. Bundles of exceedingly fine nerve-fibres, much resembling those in the bladder, can be seen running in different directions and branching amongst the delicate networks of exceedingly fine muscular fibres. Very fine fibres may be observed in thin specimens with the aid of high powers, crossing the fine muscular fibres at different angles, then dipping down in the intervals between them, and being soon lost in consequence of their ramification in the deeper layers. In this drawing the relation of the nerve-fibre to the finest part of some of the branching muscles of the tongue is represented ; and I have observed an arrangement precisely similar in the case of the muscular walls of the lymphatic hearts of the same animal. The very thin and narrow mus- cular fibres of the heart and tongue would appear to offer very many ad- vantages for the demonstration of ends and end-organs, supposing them to exist ; but the most careful observation under the most favourable circum- stances and with the aid of the highest powers, reveals only delicate nu- 250 Dr. Beale — Croonian Lecture. [May 11, cleated nerve-fibres, forming lax networks, branches of which may often be followed for a very long distance, and then traced into neighbouring nerve- trunks. Of the finest nerve-fibres which influence the muscle. It is probable that the active part of the nerve-fibre, as regards the ele- mentary muscular fibre, commences only at the point where the dark- bordered character of the nerve-fibre ceases, and therefore that the most important and most active portion of the peripheral nerve-fibres distributed to muscle, has escaped the observation of many observers. The fibres are extremely delicate, and, like other very fine nerve-fibres, can only be rendered visible by special methods of preparation. Probably every fibre, however fine, is compound, being composed of several finer fibres. Nuclei are in- variably found in relation with these fibres, and they vary in number in different cases. The structure and general appearance of the finest nerve- fibres will be understood by reference to the figures. From the foregoing observations I conclude that the nerve-fibres which are to be regarded as the fibres of distribution are far more delicate and much finer than has been hitherto supposed. The remarks which I make on this head with reference to the ultimate nerve-fibres distributed to volun- tary muscle, will apply to the ultimate nerve-fibres distributed to other organs. In mammalia the ultimate fibres appear as narrow, long, slightly granular, and scarcely visible bands with oval masses of germinal matter, situated at short but varying intervals, as described in my paper published in the Phil. Trans, for 1860. In many reptiles (frog, newt, lizard, snake, chameleon), however, these ultimate nerve-fibres are narrower but much firmer than in mammalia; and they are more readily demonstrated, as they do not give way under the influence of considerable pressure and stretching. Although fine nerve-fibres have been described in certain situations before I drew attention to these fine pale nucleated fibres in muscle, it was not generally supposed that the active peripheral portion of nerves exhibited these cha- racters; nor indeed has this fact yet received the assent of many distin- guished anatomists. The arrangement of the fine nerve-fibres in the summit of the papillao of the frog's tongue, described in my last paper presented to the Royal Society (Phil. Trans. June 1864), and in the mucous membrane of the human epiglottis, will, I venture to think, tend to con- vince many that the really active peripheral portion of the nervous system consists of excessively fine nucleated nerve-fibres arranged as a plexiform network. "With reference to the diameter of these finest branches of the nerve- fibres, many can be demonstrated and followed for long distances which are less than the j^jVuTfth °f an inch in diameter ; and there is reason to think that fibres much finer than this actually exist, and serve as efficient con- ductors of impressions to and from nerve-centres and peripheral parts. 1865.] Supposed Terminations of Nerve- fibres. 251 THE ESSENTIAL STRUCTURE OF A NERVOUS MECHANISM CONSIDERED. Of the supposed terminations of the dark-bordered nerve-fibres, and of the probable existence of nerve-circuits. It will have been remarked that Continental observers are unanimous in representing the dark-bordered nerve-fibre as passing to its destination unaccompanied by any other fibre whatever. In some drawings it is re- presented as terminating in a short fine fibre, which is regarded as the prolongation of the axis-cylinder ; in others, this fine fibre is represented as bifurcating so as to form two very fine fibres. Some observers consider that the "axis-cylinder" spreads out to form a band which is more or less convoluted, but terminal, forming an " end-organ," while others hold that the fibre gradually ceases or loses itself in the surrounding tissue. But while there are these minor differences, all agree in the opinion that the nerve-fibre passes alone to its ultimate "end." On the other hand, I have endeavoured to show that at least one fine nerve-fibre accompanies the dark-bordered fibre to its ultimate destination (page 241) as represented in these figures, and that this fine nerve- fibre is a constant structure of great importance. It was first fully described by me in papers in the 'Archives of Medicine ' on the frog's bladder; but its existence was referred to in my paper in the Philosophical Transactions for 1860, and its arrangement investigated in that published in the Philosophical Transactions for 1862. Some surprise may be felt that Continental observers have not specially noticed the fine fibre accompanying the dark-bordered fibre, or referred to my statements concerning it ; but as neither the fine fibre, nor indeed the finest part of the dark-bordered fibre, can be seen in specimens examined in aqueous fluids, it was scarcely to be expected that the facts I have described should have been verified in Germany. I therefore beg to direct the attention of anatomists and physiologists to the drawings to which I now point, and to my specimens. The fine fibre accompanies the dark-bordered fibres distributed to the tissues of the frog generally, but it is more easily demonstrated in relation with the nerves distributed to the bladder, to the mucous membrane of the palate, the skin, and the connective tissue about the heart and lungs, than with those of striped muscle ; it is, however, so frequently seen in the case of muscular nerves, especially in the mylohyoid of the Hyla, that I believe it is invariably present, though it cannot be demonstrated in all cases. Not only is the structure of the fibre very delicate, but it is often obscured by the dark-bordered fibre which it accompanies. Now, if a single fibre passed at once to its destination, as Continental observers suppose, it is obvious that the arrangement of the nerves in muscle must be different in principle to their arrangement in the cornea, for example, where it is admitted no " end-fibres " can be detected. But, on the other hand, as at least two fibres, and usually several, pass together to 252 Dr. Beale— Croonian Lecture. [May 11, their ultimate destination, there is at least a possibility, if not a reasonable probability, that the ultimate arrangement of nerve-fibres in muscle, the cornea, and other tissues is, in principle at least, the same. It may be remarked, further, that it is not likely that the nerve-current would be running iu the same direction in two distinct fibres situated close together, while the existing anatomical arrangement above referred to is suggestive of currents passing in opposite directions. This view is favoured by the fact of one fibre being much finer than the other — an arrangement which would be fully explained if each of the two fibres were a part of two dif- ferent circuits. My meaning will be understood at once if this diagram, to which I now point, be examined. I have endeavoured to prove that in various forms of muscular tissue, and in other textures, nothing but continuous nerve-fibres can be observed. The most careful observation has failed to show any appearance which could be considered as demonstrative of "ends" of any kind ; and although in many cases I have been unable to follow the very fine fibres resulting from the division of the nerve-fibres of one trunk into those of another trunk — although, therefore, there is, as it were, a hiatus in the evidence ad- vanced in favour of this view being universally applicable, the appearances in every one of the cases that I have examined are such as to render it almost certain that this is the real arrangement. If we find a compound nerve- trunk passing to one part of a muscle and another compound trunk passing away from another part of the muscle, in such manner as would be easily explained upon the supposition that certain of the fibres of one cord were continuous with those of the other — more especially if the action of these fibres could be explained upon such an hypothesis, we should surely be justified in inferring the continuity of the fibres, although we could not trace them through their entire course. It might be urged by an objector, that it is just at this intermediate point in many instances that the evidence fails. But it must be borne in mind that it fails in certain instances only ; for I have traced and can demonstrate, in some of my specimens, the nerve- fibres distributed to muscular tissue in every part of their course. The truth of my statements upon this anatomical question is in fact admitted in the case of certain muscles ; and those who still maintain that nerve-fibres "end" in voluntary muscle must maintain that there are some muscles in which nerves form networks, while in others they terminate in distinct ends — that in fact nerve-fibres are distributed to different kinds of mus- cular tissue upon at least two very distinct principles, although no dif- ferences whatever can be shown in the essential structure or action either of the muscular or of the nervous tissue. But the case is still stronger than this. I shall adduce a considerable amount of collateral evidence in favour of the view that nerves form con- tinuous and uninterrupted cords ; and this evidence will be derived from many different sources. A.S there is the greatest difference of opinion with regard to the arrange- 1865.] Of the Terminal Networks and Plexuses. 253 merit of the nerves in muscle, and as the question is now much involved, it seems to me of the utmost importance to consider it from a general point of view. Every careful examination that I have made with the view of ascertaining the arrangement of the nerve-fibres in various tissues has tended to confirm me in the opinion that networks and continuous circuits exist, and that there are no " ends " or " terminal extremities." Although I am of course ready to admit that no amount of argument from general considerations can upset the conclusions resulting from direct observation in special cases, I submit that the conclusions of my opponents, in the particular instances advanced by them, have never been supported by posi- tive demonstration. Indications of the appearances they have described un- doubtedly exist ; but it seems very difficult to prepare specimens which shall admit of but one interpretation, and so distinct that several independent observers would, upon examination, arrive at one and the same conclusion. It is too often urged that the specimens demonstrating " ends " and " end- organs " do not " keep," and must be examined when quite fresh, while I find no difficulty in preserving those which demonstrate " networks " and " plexuses." I desire, however, to weigh carefully every kind of evidence that can be brought to bear upon the determination of this point, which is undoubtedly one of very great difficulty. As the question, too, is a funda- mental one of the utmost importance, it is worthy of the most patient consideration. Of terminal plexuses and networks of fine nerve-fibres in the cornea and in connective tissue. From its transparency, the simplicity of its structure, and the absence of vessels over at least a great part of its extent, the cornea of the smaller lower animals presents many advantages for studying the arrangement of the ultimate nerve-fibres. My friend and former pupil, Prof. Ciaccio, now of Naples, very carefully studied this subject ; and the results of his obser- vations will be found in the Transactions of the Microscopical Society for July 1863, "On the Nerves of the Cornea, and of their distribution in the Corneal Tissue of Man and Animals," by Prof. G. V. Ciaccio, M.D., of Naples. Of the existence of nerve-networks in this tissue there can be no question ; but there is some difference of opinion regarding the manner in which the ultimate nerve-fibres are arranged. This drawing represents the nerve-fibres in the cornea of the Hyla. The relation of the finest nerve-fibres to the corneal corpuscles is a question of great importance. Kuhne has endeavoured to prove that the ultimate nerve-fibres are con- tinuous with the processes of the connective-tissue-corpuscles, and that there is an actual continuity of tissue, such as he believes exists between the nerve-fibre which perforates the sarcolemma of muscle and the pro- toplasmic matter which is in actual contact with the contractile tissue. Careful observation, with the aid of the -^ and -^-object-glasses, has convinced me that there is no such arrangement as Kiihne supposes, but u 2 254 Dr. Beale— Croonian Lecture. [May 11, that the nerve-fibres pass over or under the prolongations from the corneal corpuscles without being continuous with them. The fundamental arrange- ment here seems to be the same as elsewhere. The nerve-fibres run amongst the tissue, but they are continuous neither with the proper fibrous tissue of the cornea, nor with its nuclei ; and if any influence is exerted by the nerve upon the tissue or upon the nuclei, it is probably effected by the current which is transmitted by the fibre, and is not due to any direct continuity of texture. The figure to which I now point, represents a thin layer of the connective tissue covering the posterior part of the mylohyoid muscle of the Hyla, with the nerves and vessels. The bundles of fine dark-bordered fibres can be very readily distinguished from the fine fibres given off from them and forming a very extensive network in every part of the tissue. In this specimen, fibres can be traced from the nerve-trunks to the capillaries, as well as to the nerve-network of fine fibres imbedded in the connective tissue. If the reader imagines muscular fibres placed in the meshes of this net- work, he will, I believe, have a correct idea of the manner in which nerve is distributed to muscle. (See figure on opposite page.) The same facts are demonstrated in my specimens of connective tissue from the abdominal cavity of the frog, the outer surface of the lungs, &c. The distribution of the finest nerve-fibres to the mucous membrane of the epiglottis of the human subject is also upon the same plan, but the finest nerves are more difficult to demonstrate. In this figure the capillary vessels and the nerves, as they lie immediately beneath the epithelium, are represented ; and in this one a small portion of the tissue cut exceed- ingly thin, from one of the intervals between the capillaries, is represented magnified by the -£%. Fine nerve-fibres distributed to capillaries in the form of networks and plexuses. It has been already shown that fine nerve-fibres are distributed to the cornea, to the fibrous tissue in the abdomen of the frog, and to that of the pericardium and of other parts, which is destitute, or nearly destitute, of vessels, and which at the same time is a tissue which can scarcely be regarded as being more immediately influenced by nerve-fibres than the ordinary forms of cartilage, which are undoubtedly destitute of them. To assert that these fibres are in some manner directly concerned with the mftritive process is begging the question ; and as cartilage is undoubtedly developed and nourished without the direct influence of nerve- fibres, it is probable that the nutrition and development of such tissues as the above, which are closely allied to cartilage, do not depend upon the nerve-fibres which are distributed to them. These nerve-fibres probably perform a totally different service. Pale nucleated nerve-fibres are also distributed to capillary vessels, as is well shown in the figures to which I now direct attention. That the fibres 1865.] Nerves Distributed to Capillaries. 255 seen in the specimens from which these drawings have been taken are true nerve-fibres, is proved by the circumstance of their having been followed from or into undoubted nerve-trunks. The evidence I have adduced iu Connective tissue covering part of the mylohyoid muscle of the frog, and extending from its posterior portion, a. Capillary vessels, with their nerve-fibres, b. Bundles of fine dark-bordered nerve-fibres, from which fine nerve-fibres may be traced to the capil- laries, and to their distribution in the connective tissue, where they form networks of exceedingly fine compound fibres. The engraving represents the specimen as magnified only 110 diameters; but the original drawing was taken from it when magnified by a much higher power. favour of this view, is of the same nature as that which is admitted to prove 256 Dr. Beale — Croonian Lecture. [May 11, the nervous nature of the fibres distributed to muscle itself; indeed, if these fibres distributed to the capillaries are not nerve-fibres, none of the fine fibres in the cornea, fibrous tissue, &c. already alluded to and represented in my drawings, are nervous. Fine nerve-fibres can be followed from the nerve-trunk, and traced to their distribution on capillary vessels, as repre- sented in this drawing, and as I have also shown to be the case in my Memoir " On the Papillae of the Frog's Tongue," presented to the Royal Society in June 1864. Some of the fibres can be traced from the imme- diate neighbourhood of the capillary, where they for the most part ramify, in the surrounding tissue, and may be followed to the point where they pass into undoubted nerve-trunks. With reference to the office performed by these nerve-fibres, a care- ful consideration of all the facts I can ascertain in connexion with this question, leads me to the conclusion that these fibres, close to the capillary vessels and in tissues destitute of capillaries, are not concerned in special sensation, but are the afferent fibres to the nerve-centres in which the efferent fibres distributed to the small arteries take their rise. I believe that these fibres do exert an influence upon the process of nutrition, but only by their indirect influence upon the nerves which govern the calibre of the small arteries transmitting the nutrient fluid to the capillaries nearest to the tissues in which they ramify. Although time precludes me from entering into this part of the inquiry, I may be permitted to allude briefly to the mechanism which I believe is concerned in regulating the nutritive process, as it occurs in the tissues of man and those higher animals whose nutritive operations continue to be carried on with comparatively little alteration under very varying external conditions. The arrangement I am about to describe appears to be, within a certain range of variation, self-adjusting. If, however, the limits be overstepped in either direction, as not unfrequently happens, under the very artificial conditions to which man and many of the domestic animals are exposed, the range of self-adjustment is exceeded, and oftentimes a part of the mechanism is completely destroyed and can never again be effectually repaired or replaced. It is obvious that the afferent fibres above referred to, must be affected by any alterations occurring in the flow of pabulum to the tissue in their immediate neighbourhood. Suppose, for example, the quantity of nutrient pabulum flowing to the cells of a tissue to which nerve-fibres of this class are distributed, to be unusually great, these nerve-fibres would necessarily be compressed by the swelling of the surrounding elementary parts which absorb the pabulum. This pressure would, in the first instance, so affect the nervous centre as to cause a change in the condition of the efferent nerve-fibres, which would induce contraction of the small arteries trans- mitting the blood to the capillary vessels, and thus the quantity of pabulum sent to this locality would be immediately reduced. The nuclei of the nerve-fibres would also participate in the increased absorption of nutrient 1865.] Arguments in Favour of Uninterrupted Circuits. 257 matter ; but precisely in what manner, I must not now discuss. If, however, the conditions which led in the first instance to the increased nutrition persisted, the pressure upon the nerve-fibres might go to the extent of paralyzing them, in which case the small arteries would become dilated ; the capillaries must in consequence be fully distended with blood, and that congestion which constitutes one of the earliest stages of inflammation as it occurs in man and the higher animals, would result. I have already indicated the wide differences in structure, mode of growth, and in the changes occurring during action, between the spherical and oval nerve-cells, and the so-called caudate nerve-cells. These differences are sufficiently marked to justify me in regarding them as two distinct classes of central nerve-cells performing very different offices or functions*. Several considerations have led me to conclude that the oval and spheri- cal ganglion-cells are the sources of nervous power, while the so-called caudate nerve-cells in the cerebro-spinal centre are the points at which several different nerve-circuits intersect, and probably act and react upon one another. The marvellously complex and combined nervous actions depend, in all probability, upon the perfection attained by this latter part of the nervous mechanism. I have been led further to the opinion, not only that the spherical and caudate nerve-cells are concerned with the reflex phenomena of the vascular system, but that those forming the ganglia on the posterior roots of the spinal nerves are intimately connected with the general reflex actions occurring in the voluntary muscles when the cord is divided transversely. From the arrangement of the vascular nerves dis- tributed to the vessels of muscles, it is easy to understand how, by an increased action of these vascular nerves, the contraction of the muscles of a limb might be caused. I have demonstrated that connexions exist between the peripheral portion of purely sensitive nerves and the nerve- fibres distributed to the tissues in which capillaries ramify, as well as to capillary vessels themselves. These connexions would account for the excitation of involuntary reflex actions by the application of a stimulus to the general cutaneous surface. If this view be correct, the ganglia on the posterior roots of the nerves, rather than the different segments of the spinal cord, must be regarded as the centres of reflex actions and also as the nervous centres which, with the so-called sympathetic ganglia, preside over all the vascular, and, through the vessels, over the nutritive pheno- mena of the body. The facts and arguments in favour of these general conclusions will form the subject of a separate memoir. Arguments in favour of uninterrupted circuits, deduced from an examina- tion of the trunks of nerves, and arrangement of nerve-centres. One is somewhat surprised that the mode of branching of nerves, referred to generally in pp. 239, 240, which is so universal, has not been dwelt upon * See my paper " On the Apolar, Unipolar, and Bipolar Nerve-cells," &c., Phil. Trans. 1863, and a paper entitled " Indications of the Paths taken by the Nerve-currents," &c., Proceedings of the Koyal Society, yol. xiii. p. 386. 258 Dr. Beale— Croonian Lecture. [May 11, and carefully described by those who have written upon the structure and arrangement of nerves. The nerves distributed to a tissue or organ are often represented as if they all passed straight to their terminal distribu- tion, while the invariable arrangement is such as to lead to the inference that, of the fibres composing a bundle of nerves, some are proceeding in a direction from, and others towards the nerve-centre or peripheral part; and this is observed not only in purely motor, but in purely sensitive, as well as in mixed nerves. It is also found in the case of the sympathetic system, and is to be demonstrated in all animals. It is, however, not pos- sible to dissect the trunk of a fine nerve and render it sufficiently trans- parent to display these facts, if the ordinary methods of examination be adopted ; but by the plan of investigation I have fully described, the arrangement may be readily demonstrated in the nerves either of the higher or lower animals, although with the greatest facility in the Hyla*. Few anatomical facts seem to me of more interest and importance in their general bearing upon the physiology of the nervous system than that above alluded to. Its constancy proves its importance, if it does not alone compel us to infer that it is essential. What explanation, then, can be offered of the three sets of nerve-fibres which can invariably be traced at the point where a nerve-fibre comes off from a trunk passing at right angles to it, as represented in these figures ? Look at it how we may, there must be three sets of fibres in all cases ; and just as we find that the nerve- fibres constituting the roots of the nerves divide soon after their entrance in the spinal cord into bundles which pursue many different directions — some passing upwards towards the brain, others downwards towards the lower segments of the cord, and some to the opposite side, as has been well shown by the researches of Lockhart Clarke — so in the case of every nerve-fibre which appears to pass into or come from an adjacent nerve-trunk, fibres pursue three different courses, as shown in these drawings. These may be afferent, efferent, and commissural; and there are fibres commissural as respects different parts of the peripheral system as well as of the central organ. Thus, I believe, may be explained the action of each papilla as a separate organ, independently of its neighbours, or the harmo- nized action of several different papillae. By the same arrangement I con- sider the harmonious action of the several elementary fibres entering into the formation of muscle is effected. As has been before observed, the large compound nerve-cords or trunks, the finer bundles, and the finest constituent fibres of the pale terminal nerve-fibres exhibit the same general arrangement. The remarks already made with reference to the course of the fibres in the nerve-trunks and the branching of the dark-bordered fibres, also apply to the finest fibres ; and at the point where a fibre passes off from another at right angles, the ex- istence of the three sets of fibres can be demonstrated. I would draw * How to work with the Microscope. Third Edition, p. 204. See also " On the Branching of Nerve-trunks," &c., Archives, vol. iv. p. 127. 1865.] Of the " Terminations" of Nerves in Papilla, $c. 259 attention to the arrangement shown in these drawings, and especially to that represented in this figure ; not that I would maintain that in the finest fibres these three fibres are separated from one another or insu- lated by a layer of white substance, but, on the contrary, I consider that in many cases these fine fibres, although they may often be split in the longitudinal direction, nevertheless in their natural state form almost homogeneous fibres, the material of which may permit the passage of nerve- currents in the different directions indicated. It is very probable that the passage of the currents along precisely the same paths for a con- siderable time may cause the decomposition of the nervous matter in such a manner as to give rise to distinct lines, which might readily be mistaken for separate fibres, and after a time lines of fibres in an ap- parently transparent tissue would result*. At an early period of de- velopment, nerves form a sort of thin expansion, in which the appear- ance of fibres crossing one another in various directions may be after- wards produced by the passage of the nerve-currents. Beneath the ex- ternal investment of the common fly and many other insects, and beneath the soft, delicate perivisceral membrane of mollusca, I have seen the most beautiful and elaborate arrangement of apparent nerve-fibres of such a character as to justify the above inference. In the cornea, that part of some of the nerve-fibres from which several fine bundles radiate in different directions exhibits lines or fibres crossing one another in every direction which the emerging fibres take. This subject is capable of much further elucidation, and is well worthy of being considered in detail ; but in this Lecture I onlv allude to it cursorily because it bears, in a most important manner, upon the question of unin- terrupted nervous circuits, and affords an explanation of the manner in which the complex arrangement which nerves ultimately exhibits is brought about. Of the" termination" of nerves inpapillce and in special cutaneous nervous organs, such as the papillae concerned in touch and taste, and in the Pacinian corpuscles. Now in highly elaborate nervous organs like the papillae of the frog's tongue, which are very minute, and situated comparatively close to one another, we have an opportunity of studying, under great advantages, the course pursued by the constituent fibres of a bundle of nerves. And although even here it is not possible to follow a single fibre for any great distance, a careful consideration of what can be demonstrated leads to the inference that to every one of these papillae three sets of nerve-fibres are distributed. I have always been able to demonstrate in the peripheral organs that I have examined more than a single nerve-fibre; and where, as is almost * Indications of the Paths taken by the Nerve-currents, &c. : Churchill and Sons. 260 Dr. Beale — Croonian Lecture. [May 11, invariably the case, numerous terminal organs exist, these are always connected together by nerve-fibres which pass from one to the other. Although the arrangement is not always so distinct as represented in this drawing of the papillae from the tongue of the frog, I always find that where a nerve-trunk divides into two sets of branches, there exists at the point of division a fibre or fibres which seem to connect the two terminal organs to which the bundles of fibres pass. Passing to every touch-body in the papillae of the skin of the finger, I find more than one nerve- fibre ; and the corpuscle itself seems to consist of a very much coiled and reduplicated nucleated nerve-fibre, as represented in this drawing. In the peripheral cutaneous nervous organs of many invertebrate animals which I have examined, especially in some of the insects and annelids, I find a bundle of nerve-fibres, not a single nerve-fibre, as is usually repre- sented. This drawing illustrates the view generally entertained ; and this one, my own inference of the structure of these organs. Even in the Pacinian body I find no such indications of a true termination of the axis- cylinder as is usually described : not only so, but in many cases 1 have seen three or four very wide lobe-like continuations of the axis-cylinder bending downwards from its highest point, and passing apparently into very fine granular fibres which lie between the laminated capsules, and are continued into the nerve-sheath. The drawing will illustrate the struc- ture of all these allied peripheral nerve-organs, according to my observa- tions. Evidence in favour of continuous nerve-circuits, derived from the study of the development of nerve-fibres distributed to muscle. The development of nerves distributed to muscle is most difficult to investigate, but it is a subject well worthy of most attentive study ; and although I cannot hope to give a clear account of the process, I shall make an attempt to describe what I have myself seen. The relation of nerves to the contractile tissue of muscle and other tissues, and the general arrange- ment of nerve-fibres, having been determined, one cannot avoid asking how the fibres became arranged as we see them in the fully formed texture. Of the part taken by the masses of germinal matter there cannot be the slightest doubt ; for it can be shown most conclusively that as the nerves advance from the early to the complete stage of their development, the distance between the several masses of germinal matter gradually increases. This may be proved in the case of dark-bordered as well as of "very fine nerve-fibres. It is well shown in these figures. At an early period of the development of muscle, very numerous masses of germinal matter are seen amongst the muscular fibres, in which transverse markings are already developed. These, as I have been able to satisfy myself by researches upon the diaphragm and intercostal muscles of the foetal dog, are con- cerned in the formation of nerves and capillaries. In the young caterpillar the surface of some muscular fibres seems to be 1865.] The Development of Nerve-fibres. 261 completely covered with nuclei ; and as development advances these nuclei or masses of germinal matter seem to separate further and further from one another, and the delicate nerve-fibres might be said to be drawn out from them. At the same time the muscular fibre increases in size. It will pro- bably be conceded that at an early period of development of a muscle there are masses of germinal matter taking part in the development of the three different structures — muscle, nerves, and vessels. Besides these, upon the surface of the muscle, and between the muscular fibres, are masses which have perhaps already given rise to the formation of a soft granular and slightly fibrous connective tissue. I think that these last masses have originated from the same parent masses as the others. Indeed it is certain that this must be so. Of the masses taking part in the development of a bundle of nerve-fibres, those on the surface produce not true nerves, but connective tissue, and so with regard to muscles, vessels, and other textures. The part taken by the germinal matter in the development of muscles, nerves, and vessels may be studied in the fully-formed frog, and with greater facility than in the embryo. At certain intervals amongst the large muscular fibres of the frog may be discovered with some difficulty some bundles of finer muscular fibres. These are most distinctly seen, however, in the thin breast- muscle of the frog, where they were discovered by Kolliker. They were termed by him " nerve-tufts," and are figured in his Croonian Lecture, delivered in 1862 (Proceedings of the Royal Society, 1862, p. 78). I have had Kolliker' s figure copied. It does not, how- ever, represent all that may be seen in these swellings, prepared according to the particular plan before alluded to (p. 258); for the numerous oval nuclei, figured in Kolliker's drawings, are represented by him as being pretty generally diffused throughout the swelling, and as not being con- nected with one another, or with any definite structure. The relation of the nerve-fibres to these nuclei is not indicated in Kolliker's drawing, nor is the meaning of these numerous nuclei discussed. Some of the nuclei (masses of germinal matter), however, are seen in my specimens to be nuclei in the course of very fine nerve-fibres — nuclei which take part in the formation of the nerve-fibres themselves. Others are the nuclei of the muscular fibres which are undergoing development, and over the surface of which the fine nerve-fibres are spread out. These facts are demonstrated in several specimens which I have mounted in strong glycerine and acetic-acid syrup*. A portion of one of these is represented in the figure to which I now point. This drawing, which is magnified 700 diameters, appears somewhat confused, owing to the very close proximity of the nerves to the muscles. It is, however, a careful copy of one of my specimens just at the spot where three dark-bordered nerve-fibres pass into, or emerge from, one of the " nerve-tufts." In this drawing I have shown one branch of a dark-bordered nerve-fibre and its division into two very fine * " I have found this strong acetic-acid syrup a most valuable agent in these and kindred investigations." — How to Work with the Microscope, third edition, p. 202. 262 Dr. Beale — Croonian Lecture. [May 11, fibres. These may be followed for a considerable distance amongst the developing muscular fibres. It has been truly stated by Kolliker that the apparently single muscular fibre bearing the swelling is really a bundle of very fine muscular fibres, varying from three to seven, or more, in number, and that the apparently penetrating nerve-fibres merely pass between these imperfectly developed muscular fibres. I cannot, however, agree with him in the view that the fine muscular fibres result from longitudinal splitting of wider fibres. The bundles of fine muscular fibres under consideration extend, it is true, at a certain period of their development, from one extremity of the muscle to the other ; but all the muscular fibres of the bundle do not reach so far. In one bundle sometimes ten or twelve distinct muscular fibres, very closely packed together, may be counted. Near the swelling the muscular fibres are wide, and the fine, tapering, pointed extremities of other young mus- cular fibres can also be seen. These spindle-shaped muscular fibres are not nearly so long as the ordinary fully developed muscular fibres. In fact, at the swelling, several spindle-shaped, nucleated, already transversely striated muscular fibres may be observed, and the stages through which the elementary fibres of voluntary muscle pass in their development may be traced. In these "nerve-tufts " we may indeed study, in the fully-formed animal, striped muscle and nerve in every stage of development. Vessels cannot be traced into the youngest tufts ; but in those which consist of several partly grown muscular fibres, capillaries are to be seen ; so that the develop- ment of muscles, nerves, and vessels can be studied in these imperfectly developed "tufts." From the above observations, it will be seen that I cannot agree with Kolliker in the view he has taken of these bodies. He says, " Now if it be admitted that the finer muscular fibres composing the bundle are gene- rated by the division of thicker muscular fibres, as Weismann justly con- cludes, the explanation of the nerve-tufts becomes easy, inasmuch as they may be conceived to arise from a simultaneous growth and division of the nerve-fibre belonging to the parent muscular fibre, in order that each of the young muscular fibres may obtain its branch of nerve" (Croonian Lecture, May 1862). So far from the narrow young muscular fibres resulting from the division of old ones, the young muscles and young nerves are developed from col- lections of nuclei or masses of germinal matter, precisely resembling those which are found in the embryo. I believe this to be an invariable law. Many facts make me feel confident that it is quite impossible that new textures can be formed by the subdivision of old ones. Formation and development take place upon precisely the same principle in young and old tissues, in health and disease, in simple and complex organisms. New muscular fibres may be developed from old ones in this way : — the " nuclei" may increase in number, the old muscular tissue may undergo disintegra- 1865.] The Development of Nerve-fibres. 263 tion and disappear, in fact the nuclei may live and increase at its expense, and a new mass, consisting entirely of nuclei, or masses of germinal matter, by the agency of which .the formed material of the new fibres is at length produced, may result ; but never does old tissue split up into new tissue. As I have pointed out on many occasions, in fully-formed organs there exists a certain proportion of embryonic germinal matter, which may un- dergo development at a future period of life, and if the greater part of this becomes fully-formed tissue, still there remains embryonic matter for de- velopment at a still later period, and so on. In the situations of these so- called nerve-tufts in the breast-muscle of the frog, new elementary muscular fibres are added to those already formed, and the muscle grows as the frog advances in age. In the formation and growth of the muscular fibres, and in the formation and arrangement of the nerves around them, the move- ments of the several nuclei or masses of germinal matter to which I have drawn attention, play no unimportant part. (See my paper " On the movements of the living or germinal matter of the tissues of man and the higher animals," Archives, vol. iv. p. 150.) With reference to the nerves supplying these so-called nerve-tufts, I would remark — 1. That two dark-bordered nerve-fibres, running in the same sheath, may often be traced to one part of the " nerve-tuft." 2. Besides the dark-bordered fibre or fibres, there are invariably very fine fibres running in the same sheath. 3. That the dark-bordered fibres and the accompanying fine fibres divide and subdivide very freely amongst the young muscular fibres, and that thus quite a leash of very fine nerve-fibres results, in the course of which numerous nuclei exist at certain intervals. Many of these can be followed upon or between the muscular fibres, for the distance of the twentieth of an inch or more from the oval swelling. These points are well seen in the figures to which I now direct attention. 4. That the dark-bordered fibre or fibres which enter at the tuft are not the only nerve-fibres distributed to these bundles of muscular fibres, but that invariably a bundle, consisting of two or three fine but dark-bordered fibres, is connected with the muscular fibres, at a point above or below that at which the swelling is situated, where the large fibre or fibres enter. Sometimes there are two such bundles, one above and one below. These not unfrequently give off branches, just before they pass to the muscular bundle, which pursue a longer course, and are distributed to other larger muscular fibres ; and oftentimes branches pass from one muscular bundle to more distant ones. From the above observations it follows that these "nerve-tufts" in the breast-muscle of the frog consist of developing muscular fibres, which are freely supplied with nerves ; and the number and distribution of the nerves render it probable, not only that there are entering and emerging fibres, nerve-loops, and plexuses, or networks, upon the muscular fibres, rather 264 Dr.Beale— Croonian Lecture. [May 11, than free ends, but that the action of the new muscular fibres may be har- monized with those of the other and older elementary muscular fibres of the muscle by branches of nerve-fibres which are probably com- missural. I will next venture to consider the nature and origin of the nuclei taking part in the development of the muscular nerves ; and I would remark that in the frog it is comparatively easy to study the formation of even complex organs out of what used to be called a granular blastema. In each suc- ceeding spring-time not only new ganglion-cells but new ganglia and nerve- fibres, as well as vessels, are developed, and take the place of those which attained their perfect condition in the previous year, but which, having performed their work, have wasted and become converted into mere debris, a great part of which was removed during the period of hybernation. Now the formation of a new ganglion, of new muscular fibres, of new ves- sels, and other tissues, and even the formation of elementary organs of com- plex structure (as I have ascertained specially in the case of the uriniferous tubes of the newt), results from changes taking place in a collection of small spherical masses of germinal matter ; and these collections themselves seem to result from the division and subdivision of at most a few masses, all of them of course being the descendants of the original germinal mass formed when impregnation occurred. Now it may be affirmed most positively, that an entire organ, such as the kidney-tube, or an elementary fibre of muscle, is not formed first and the nerve then spread over it, but the development of the tissue to be influ- enced proceeds puri passu with the development of the nerves which are to influence it. And in the adult animal, where the development of new nerve-fibres takes place, new muscles, &c., are developed in relation with them. I have reason to think, indeed I feel confident, that new nerve- fibres cannot be developed so as to influence an old muscular fibre, or old nerve-fibres caused to influence newly developed muscular tissue ; and in the wasting of certain muscles, or other complex tissues, to which nerves are distributed, as may be studied in the frog, all the old tissue seems to be destroyed and removed by the increase of the germinal matter of the respective tissues. Hence it may be stated positively that in every case the new tissue is developed from a mass of " formless blastema " — that is, from a collection of spherical masses of germinal matter which could not be distinguished from the embryonic mass or collection which forms the early condition of every living thing in nature ; and in the destruction and removal of every tissue and organ, masses of germinal matter, often resulting from the division of those of the tissue itself, absorb, remove, and in fact live at the expense of, the tissue which is to disappear ; and whether this change occurs physiologically (that is, as a normal change at certain periods in a healthy and well-developed animal) or pathologi- cally (that is, in an organism which has been subjected to the influence of conditions more or less adverse to its well-being), the process is essen- 1865.] The Development of Nerve-fibres. 265 tially of the same nature ; and it would indeed be very difficult to dis- tinguish a collection of spherical masses of germinal matter, from which the tissues of a new being are to be evolved, from a mass of young pus- corpuscles, which may result from the rapid multiplication of masses of germinal matter existing in any tissue of man or the higher animals. In both cases the matter is formless; and however much the conclusion may be opposed to the affirmations of great authorities, we are compelled, by a review of the facts ascertained by observation, to infer that there is a far greater difference in the power than there is in the chemical characters, or physical properties, of the matter taking part in these changes. Many very interesting and highly important facts relating to this in- quiry may be obtained from a careful study of the minute changes which occur in the development of the tissues of the imago or perfect insect during the chrysalis stage. So far as I am able to ascertain, the larval tissues and organs are in the first instance completely removed, the ger- minal matter increases considerably in quantity, and at length a collection of new masses of germinal matter results, which take part in the formation of the new tissues of the developing imago. If those who so confidently affirm that all the phenomena of living beings are physical and chemical would investigate some of these marvellous changes, I venture to think they would very soon withdraw their confident assertions, and admit that the construction of tissues and organs is a process not to be explained by physics and chemistry, or accounted for by any of the known laws of ordinary lifeless matter or force. I must now advert to a question which I feel incompetent to grapple with, though I cannot permit myself to pass it over. Let me consider if, in the development of new muscular fibres, nerves, and vessels, as occurs in the case of the nerve-tufts of the frog, or in the development of a new ganglion connected with the sympathetic, there are certain masses of germinal matter which, as the direct descendants of pre-existing masses in muscles, nerves, vessels, &c., take part in the development of these tissues respec- tively, or if they all result from changes occurring in what would be called by some a mass of undiiferentiated blastema ? In studying the early deve- lopmental changes taking place in the embryo, one discovers nothing which would justify the inference that one set of masses is concerned in the de- velopment of all the future muscles of the body, another of all the vessels, another of all the nerves, another of all the glandular organs, and so on, — each of these masses or collections being gradually prolonged to distant parts ; but it seems rather that the whole is in the first instance formless, and that the process of formation gradually proceeds in many parts at the same time. The brain is not formed first, and other parts of the nervous system extended from this central organ ; but the active nervous system, central and peripheral, is developed as a whole, stage succeeding stage, until it attains its fully developed condition in all its parts. If masses of germinal matter for the development of the respective tissues were first formed, and 266 Dr. Beale— Croonian Lecture. [May 11, an extension from each of these to distant parts took place, it must follow that the portion first formed would be the oldest; but all observation seems to show that development gradually goes on in different and distant parts at the same time. And I infer that in the process of regeneration of the lobster's claw, or of the lizard's tail, of the fully formed animal, the several tissues constituting the organs are entirely developed anew from a formless mass, and not by the simple extension of the tissue of the muscles, nerves, vessels, &c., which exist in the stump. In the first instance there results a soft material, which exhibits no indications of definite structure ; and as development proceeds, the masses of germinal matter taking part in the development of nerves are seen arranged in lines, and are continuous with those in the nerves of the stump. It is, however, possible that new masses of germinal matter may grow and multiply from these latter and extend into the soft indefinite tissue first produced and destined to serve only a very temporary purpose ; but, before I can consider this question advan- tageously, I must make further observations. And it appears from ob- servations in the case of the frog, that when a new peripheral part or organ is developed, new central nerve-cells are developed in connexion with it. And it is probable (indeed it appears to me certain) that even in man this development of new central and peripheral organs goes on in certain instances. For example, at each pregnancy in the human female, it is pro- bable not only that new muscular fibres, vessels, nerves, &c. are developed in connexion with the growing uterus, but that new nerve-centres are also produced, with which the new nerves are connected ; and I regard it aa most probable that during the development of the lizard's tail and lobster's claw new central nerve-cells in connexion with the new nerve-fibres are developed in the already existing but comparatively simple nerve-centres. Of the relation of the ultimate branches of the nerve-fibres to the elements of the tissue and to the germinal matter. In no case does the nerve become continuous with any part of the con- tractile tissue of muscle ; nor is it connected with the nucleus of the mus- cular fibre or with that of any other tissue. The ultimate nerve-fibre bears the same relation to the contractile tissue of muscle that it bears to fibres of white fibrous tissue, to cells generally, and to the processes of cells, such as the prolongation from the pigment- cells of the frog, those of the corneal corpuscles in the cornea, &c. The arrangement is such as would lead us to infer that the tissue is influenced by the current passing through the nerve, not by any change involving an anatomical continuity of structure from the nerve to the tissue affected by it, or even in actual contact with any part of it ; for in very many instances we can prove that the nerve is not in very close contact with the tissue it influences. Moreover, results resembling those which occur from the action of a nerve may be brought about by the passage of a current of electricity through a wire situated at a considerable distance from the muscle, and 1865.] Structure and Arrangement of Ganglion Cells. 267 separated from it by non-conducting media ; so that, as I have before men- tioned, it would seem probable that the varying degrees of muscular contrac- tion are induced by the varying intensity of the current transmitted along a continuous nerve-fibre. Arguments in favour of the existence of continuous nervous circuits founded upon the structure and arrangement of ganglion-cells. In a paper already referred to, communicated to the Royal Society in 1864, and published in the 'Transactions,' I endeavoured to show that certain ganglion-cells which had been considered to be apolar or unipolar were invariably connected with at least two nerve-fibres, and that in many cases one of these fibres was coiled spirally round the other, as is well shown in this drawing. These two fibres often appear as one ; but not only have I succeeded in demonstrating that they are derived from different parts of the same cell, but that they pursue opposite directions in the nerve-trunks. I have been led to conclude that all nerve-cells give origin to more than one nerve-fibre, and that these fibres, although they run parallel to one another for a short distance, diverge and pursue very different and indeed opposite courses ; and I endeavoured to show that the arrangements I had observed received a ready explanation upon the view of the existence of complete nervous circuits. In another communication previously referred to, published in the 'Proceedings' of the Royal Society for 1864, entitled "Indications of the paths taken by the nerve-currents as they traverse the caudate nerve-cells," I showed that there existed in the caudate nerve-cells of the spinal cord and medulla oblongata a remarkable series of lines, which passed from each fibre connected with the cell across the body of the cell into every other fibre which diverged from it. I regarded these as indications of the paths taken by the nerve-currents which traversed these cells, and my observa- tions led to the inference that every single cell was the seat of decussation, and therefore formed part of the course, of a vast number of different nervous circuits. Upon this view of the constitution of the highly complex central organs of the nervous system, it is not difficult to account for the marvellous number of distinct actions effected, or of the still more wonder- ful combinations of actions which must occur in the great central organs of the nervous system of man and the higher animals. The axis-cylinder of each dark-bordered nerve-fibre probably forms the common route along which nerve-currents pass from many different parts in the nerve-centre to as many different points in the periphery. Fibres prolonged from several different nerve- cells seem to combine to form one dark-bordered fibre ; but these and other points will be readily understood by a cursory examination of the diagrams to which I now direct attention, so that it is unnecessary for me to describe them minutely. GENERAL CONCLUSIONS. To sum up briefly the results of this prolonged inquiry. The first import- 268 Prof. Sylvester on Newton's Rule for the [May 18, ant point is, that in no tissue have I been ahle to demonstrate an ' end' to a nerve. In all cases the nerve-cell or nucleus exhibits fibres proceeding from it in at least two opposite directions. The apparent cessation or thinning off of the nerve-fibre in many tissues results from its becoming so thin as to be invisible, unless special methods of investigation are resorted to. It has also been shown that near nervous centres, and near their peripheral distribution, the bundles of nerve-fibres and the individual nerve-fibres divide into very numerous branches. The bundles of coarse or fine fibres given off from a large or small trunk consist of fibres which pursue opposite directions in that trunk, one set passing as it were from, the other towards, the nervous centre. The nerves distributed to striped muscle of all kinds and to the various forms of unstriped muscle in verte- brata and in invertebrata, are arranged so as to form networks and plexuses, but no indication of terminations or ends is to be seen. These facts seem to render it probable that the fundamental arrangement of a nervous apparatus is a complete and uninterrupted circuit. This view is supported by the existence- of at least two nerve-fibres in all peripheral organs and by facts observed in the branching and division of individual nerve-fibres and of compound nerve-trunks. I have also shown that in nerve-centres it is doubtful if apolar or unipolar cells ever exist. All nerve-cells have at least two fibres proceeding from them in opposite direc- tions, and the multipolar cells in the brain and cord exhibit lines across them which are probable indications of the paths taken by continuous currents which traverse them in many different directions. The general inference from this anatomical inquiry is, that a current probably of electricity is constantly passing through all nerve-fibres, and that the adjacent tissues are influenced by the varying intensity of this nerve-current rather than by its complete interruption and reestablishment; so far as I know, no fact has ever been discovered which would justify the conclusion that there exists any arrangement for making and breaking contact in any part of the nervous system. In all cases it is probable that every nervous circuit is complete, and that there is no interruption of the structural continuity of a nerve-fibre at any part of its course. May 18, 1865. Major-General SABINE, President, in the Chair. His Royal Highness Louis Philippe of Orleans, Count of Paris, was admitted into the Society. The following communications were read : — I. " On Newton's Rule for the Discovery of Imaginary Roots of Equa- tions." By J. J. SYLVESTER, F.R.S. Received May 4, 1865. In the first part of my " Trilogy of Algebraical Researches," printed in 1865.] discovery of Imaginary Roots of Equations. 269 the Philosophical Transactions, will be found a proof of Newton's Rule for the discovery of imaginary roots carried as far as equations of the 5th degree inclusive. The method, however, therein employed offered no prospect of success as applied to equations of the higher degrees. I take this opportunity, therefore, of announcing that I have recently hit upon a more refined and subtle method and idea, by means of which the demon- stration has been already extended to the 6th degree, and which lends itself with equal readiness to equations of all degrees. Ere long I trust to be able to lay before the Society a complete and universal proof of this rule — so long the wonder and opprobrium of algebraists. For the present I content myself with stating that the new method consists essentially, first, in the discerption of the question as applied to an equation of any specified degree into distinct cases, corresponding to the various combinations of signs that can be attached to the coefficients ; secondly, in the application of the fecund principle of variation of constants, laid down in the third part of my ' Trilogy,' and, in particular, of the theorem that if a rational function of a variable undergoes a continuous variation flowing in one direction through any prescribed channel, then at the moment when it is on the point of losing real roqts, not only must it possess two equal roots (a fact familiar to mathematicians as the light of day), but also its second differential, and the variation, when for the variable is substituted the value of such equal roots, must assume the same algebraical sign*. By aid of the processes afforded by this principle, which admits of an infinite variety of modes of application, according to the form imparted to the channel of variation, and constitutes in effect for the examination of alge- braical forms an instrument of analysis as powerful as the microscope for objects of natural history, or the blowpipe for those of chemical research, the problem in view is resolved with a surprising degree of simplicity ; so much so that, as far as I have hitherto proceeded with the inquiry, the computations, algebraical and arithmetical, which I have had occasion to employ may be contained within the compass of a single line. The new method, moreover, enjoys the prerogative of yielding a proof of the theorem in the complete form in which it came from the hands of its author (but which has been totally lost sight of by all writers, without exception, who have subsequently handled the question), viz. in combina- tion with, and as supplemental to, the Rule of Descartes. On my mind the internal evidence is now forcible that Newton was in possession of a proof of this theorem (a point which he has left in doubt and which has; often been called into question), and that, by singular good fortune, whilst I have been enabled to unriddle the secret which has baffled the efforts of mathematicians to discover during the last two centuries, I have struck into the very path which Newton himself followed to arrive at his con- clusions. * The above is on the supposition that there is no ternary or higher group of equal roots. x 2 ' 270 Drs. Fagge and Stevenson on Physiological Tests [May 18, Received May 18th, 1865. Since the above note was sent in to the Society, I have completed the de- monstration for the 7th degree, and in the course of the inquiry have had occasion to consider the conditions to be satisfied in order that a rational function of x, with r equal roots a, may undergo no loss of real roots for any assigned variation imparted to the function : for the theory of the 7th degree the case of three equal roots has to be considered, and the conditions in question are that the variation itself may contain the equal root a, and that its first differential coefficient may have the contrary sign to that of the third differential coefficient of the function which it varies when a is substituted for x — a theorem which is, of course, capable of extension to the case of an equation passing through a phase of any number of equal roots*. II. " On the Application of Physiological Tests for certain Organic Poisons, and especially Digitaline." By C. HILTON FAGGE, M.D., and THOMAS STEVENSON, M.D. Communicated by J. HILTON, F.R.S. Received May 4, 1865. (Abstract.) As the chemical processes for the detection of certain organic poisons are very inconclusive in their nature, and as many of these agents produce effects of a most remarkable kind on the lower animals, it is not surprising that their physiological action should have been employed as a test for their presence. Thus Dr. Marshall Hall suggested as a means of discover- ing strychnia, the tetanic symptoms which that alkaloid causes in frogs ; and quite recently MM. Tardieu and Roussin produced a large mass of physiological evidence, in a French "cause celebre", in which digitaline was believed to be the poison used. Those who have recommended the employment of evidence of this na- ture have always relied on the similarity between the symptoms observed in the case of supposed poisoning during life, and the effects obtained on the lower animals by the extract believed to contain the toxic agent ; and as the action of poisons on man and on the lower vertebrata is certainly not always the same, the value of these physiological tests has been much disputed, and is not now admitted by most authorities in this country. It appears to us, however, that physiological evidence may be made inde- pendent of any relation of this kind. It is sufficient that the action of the * The above is on the supposition that one of the three equal roots remains unaffected in magnitude by the variation, whilst the other two' change. If all three are to change simultaneously, infinitesimals beyond the first order and with fractional indices have to be brought into consideration; in that case, on making x=a, the variation need not become absolutely zero, but must contain no infinitesimal of the first order. And a further limitation becomes necessary in addition to the conditions stated in the text, in order that no loss of real roots may be incurred in consequence of the variation. 1865.] for certain Organic Poisons. 271 substance believed to contain the poison on the animal experimented on be identical with the known effects of that poison upon the same animal, and that these effects be capable of being produced by no other agent or, at any rate, only by a limited number of other agents. In this spirit we have conducted a series of investigations, with reference to the detection of digitaline and of certain allied substances. We selected that poison, not only because of the interest which attaches to it at the present time, but also because the chemical tests for it are peculiarly in- adequate. The animals which we employed in all our experiments were frogs. Their sensibility to small quantities of poison, the fact that they are but little liable to be affected by fear or other accidental circumstances, and the independence of their organs, which makes it possible to determine with accuracy the nature of the effects produced, have rendered them better adapted for this purpose than any other animals ; and the objection ordi- narily urged against their use, that the action of poisons on them is often different from that of the same substances on the higher animals, has no validity when the question of physiological evidence is looked at from our point of view. It has been expressly denied, by those who have advocated the use of physiological tests, that animal extracts, such as those obtained from the contents of the human stomach, or from vomited fluids, could in themselves be poisonous to the lower animals. We thought it desirable, however, to make some direct experiments upon this point; and, to our surprise, we found that in almost every instance the toxic action of such extracts was most decided and unmistakeable. The effects produced were indeed very dif- ferent from those caused by digitaline ; and we think that we have been able to distinguish quite clearly between them. Still, the recognition of the fact that these extracts exert a poisonous action, independently of the presence of any of the ordinary toxic agents, must have an important bearing upon the application of physiological evidence. Unless some points of difference should hereafter be discovered, it will render impossible the detection of many vegetable substances (among which we may mention lobelia, emetina, veratrum viride, and delphinium staphisagria) by their physiological effects. And it makes invalid (at least so far as frogs are concerned) all evidence of this kind, in which the state of the heart is not more particularly described than has hitherto been the case, so far as the frog-test for strychnia is concerned ; on the other hand, though this was not the primary object of our inquiries, we may remark that tetanic spasms were produced by none of the numerous substances with which we experimented, except veratrine and theine. It is of course well known that other agents, and notably some of the constituents of opium, produce tetanus in frogs ; but on the whole our experiments lead us to hope that this test will hereafter be found of more value than is now generally sup- posed to be the case. We have devoted a considerable number of experiments to the solution 272 Drs. Fagge and Stevenson on Physiological Tests [May 18, of the practical question, whether it be possible to obtain the characteristic effects of digitaline, not only from the extracts of liquids to which it had been artificially added, but also from extracts of the stomach-contents and vomited matters of dogs poisoned by that substance. The results of these experiments were perfectly satisfactory ; and we think that our observa- tions show conclusively that there is no difficulty in obtaining from these complex mixtures physiological effects identical with those of a pure solu- tion of digitaline. Far more difficult to decide than the question of practical applicability, is the question aa to the theoretical accuracy and conclusiveness of the physiological test for digitaline and the allied poisons. To this question we do not venture to give a positive answer. Our experiments justify, as we think, the hope that this test will be hereafter found of very consider- able value in aiding in the detection of these substances; but it can be only by the combined labours of many observers, and not merely by one series of experiments, that this point can be finally settled. The following are the conclusions at which we have arrived, and which are deduced from our own experiments in every instance, except where the contrary is expressly stated, under heading 2. 1 . Digitaline is one of a small class of substances of which the action on frogs appears to be identical. As the heart is the organ primarily affected by them, they may be called cardiac poisons, so far as frogs are concerned. 2. These substances are, besides digitaline, the Upas Antiar, the Hel~ leborus viridis, and perhaps other species of Helleborus, the Tanghinia venenifera, the Dajaksch or arrow-poison of Borneo, the Carroval and Fao, South American arrow-poisons, and the Scilla maritima. Of these we have ourselves experimented only with digitaline, antiar, the Helleborus viridis and the H. niger, and the Scilla ; and we believe that we are the first observers who have recognized the identity of the action on frogs of the last of these plants with that of the other substances placed in this group. Besides digitaline, only two of them, namely, the Helleborus and the Scilla, are likely to be the subject of medico-legal investigation in this country, and that but rarely. 3. The characteristic effect of each of these agents on frogs is the pro- duction of irregularity of the heart's action, followed by complete stoppage of its pulsations ; the ventricle remaining rigidly contracted, and perfectly pale, after it has ceased to beat ; the muscular power of the animal being at this time unimpaired, and persisting as long as in frogs in which the circulation has been stopped by other means, such as ligature of the heart. The irregularity in the heart's action, which precedes its stoppage, under the influence of these poisons is peculiar. The rhythm is but little altered ; and the beats are not necessarily diminished in number, as has been sup- posed. Sometimes, however, the ventricle makes only one pulsation for two of the auricles, the number of its contractions being therefore lessened 1865.] fur certain Organic Poisons. 273 by one half. More frequently the irregularity consists in one or more portions of the ventricle (especially the apex) becoming rigidly white and contracted, while the remainder of the organ continues to dilate regularly. When these yielding pulsations are small, a peculiar appearance, as if the wall of the ventricle formed crimson pouches or protrusions, is produced. 4. No other substance, except those mentioned above, has been found to produce this chain of effects, even in a single experiment. We have ourselves tried nineteen different substances, consisting of vegetable extracts and alkaloids. Of these, emetina, and the extract of the Delphinium staphisagria caused somewhat similar irregularity of the cardiac beats ; but in frogs, poisoned by these agents, the muscular power was always lost before the heart had ceased to beat, and the ventricle stopped in the dilated, and not in the contracted, state. 5. When digitaline is applied endermically to frogs, the characteristic effect is invariably produced, if a sufficient quantity be used. This quan- tity no doubt varies with the size of the animal, but may be stated gene- rally at Yijoth of a grain. Quantities less than yl^th grain usually produce no effect, or at most only temporary irregularity of the heart's action, of a more or less characteristic kind. The result of the injection of doses larger than T^th grain is to diminish the interval between the administra- tion of the poison and the stoppage of the ventricular beats. This interval appears to be seldom less than six or seven minutes, however large the quantity of digitaline. 6. Very poisonous effects are produced in frogs by the endermic ap- plication of alcoholic or acetic extracts of matters vomited by patients, or taken from the human stomach after death. The extracts are less poison- ous, if at all, to the higher animals. 7. The symptoms produced by these extracts in frogs are in marked contrast to those caused by the cardiac poisons. Like these agents, the animal extracts impair the action of the heart ; but their tendency is to cause paralysis of its muscle, and stoppage in the dilated condition. At the same time, they generally destroy the muscular power of the animal. 8. The cause of the toxic action of these animal extracts has not been ascertained ; it is probably not always the same, as the effects produced by different extracts are not perfectly similar. These effects are perhaps the result of the combined action of different substances. They are certainly not caused by bile or pepsine, and probably not by any substance in a state of decay. 9. The vegetable acids, when injected in sufficient quantity, stop the action *of the heart more rapidly than any poison with which we are ac- quainted, the organ remaining distended with blood when it has ceased to beat. The toxic action of the "animal extracts is not, however, caused by these acids ; for the quantity of them contained in the extracts is too small, and the effect is not diminished by neutralization with an alkali. 10. When digitaline, in quantities of \-\-\ grain, is added to vomited 274 Mr. Ellis on the Corrections for Latitude [May 18, matters, or to fluids taken from the human stomach post mortem, the extracts obtained from such fluids almost invariably produce on frogs the effects of digitaline. 11. This is due partly to the fact that the action of digitaline is gene- rally more rapid than that of the poisonous constituents of the extracts themselves, hut principally to the circumstance that it was necessary to give only small doses of the extracts containing digitaline, in order to get the characteristic action. 12. The method of dialysis fails in many cases to separate digitaline from complex organic mixtures which contain it; and this method is rarely of service in aiding the detection of this poison by the physiological test. 13. "When digitaline was administered to dogs in quantities little more than sufficient to destroy life, the extracts derived from the matters vo- mited by these animals, or from the fluids contained in their stomachs after death (when vomiting was artificially prevented), were found in each of those experiments to produce on frogs unmistakeably the effects charac- teristic of the presence of one of the cardiac poisons. NOTE.— Received 18th May, 1865. We have now to add to the list of " cardiac poisons " the Manganja, an arrow-poison, brought from the Zambesi Expedition by Dr. Kirk. Our attention was directed to this substance, which is the fruit of an Apocyna- ceous plant, by Dr. Sharpey, who informed us of the results of experiments he had made on its action ; and we owe to his kindness the opportunity of confirming his observations by our own experiments. III. " On the Corrections for Latitude and Temperature in Baro- metric Hypsometry, with an improved form of Laplace's formula." By ALEXANDER J. ELLIS, F.R.S. Received May 11, 1865. Adopting the notation in Table I. (p. 284), and the data of M. Mathieu (Annualre du Bureau des Longitudes, 1865, p. 321), Laplace's hypso- metrical formula, after some easy transformations, becomes ^— H1=[logB-log£--00007.(M'-m').]x[500+A'+a'] I8336 (\ -L 15926 Yl T .(1— *cos2L)<\ 6366198/J L t = [log B— log b— -00007 . (M'— m')] x [500+A' 36-764 In the last term in (a), hr— Hj represents the product of the three pre- ceding factors, W . T' . Ga ; and z is left for the present undetermined. If y be the total increase of gravity in proceeding from the equator to the 1865.] and Temperature in Barometric Hypsometry, §c. 275 pole, the coefficient z=y-r(2 + y')*, for which most writers employ |y, as they also commonly use 1 -f^cos 2 L for 1 4-(l — z cos 2 L). The values assigned to z by different writers vary considerably. Laplace makes ,?= -002837, and M. Mathieu (Annuaire, I.e.) gives *•= -00265. I have thought it, therefore, advisable first to consult the authorities who have calculated y directly from pendulum experiments, next to calculate y from the compression deduced from measurements of arcsf, and then, having determined z for each of these values of y, to take the mean result to five places of decimals. The pendulum reductions are taken from Baily (Mem. of Astron. Soc. 1834, vol. vii. p. 94) ; the four first reductions are cited on the authority of the Engl. Cyclop. A. fy S. vol. iv. col. 362, and the fifth from the Proceedings of the Royal Society, vol. xiii. p. 270. The following are the results. Pendulum Experiments. Baily, final result y= -005 1449 z= '0025659 Sabine, -0051807 '0025837 Airy, -0051330 -0025599 Airy, Bessel, Everest, Clarke, Pratt, Mean values y= -0052651 .?= -0026256 Hence I adopt the value £= -00263. This differs from Laplace's value by -000207, and from that of M. Mathieu by -00002. Viewed in relation to the possible errors which may arise from other sources this correction is slight, but it should be made on the principle advocated by Laplace, that it is assignable (Mec. Cel. vol. iv. p. 292). Adopting this value of z and reducing the formula (a) to English feet and Fahrenheit degrees, I have constructed Tables I. and II., which give formulae and figures for calcula- ting heights with every correction of Laplace, more readily than any other that I have seen. As there is no necessity to interpolate, the Tables are even simpler to use than M. Mathieu's (Annuaire, 1. c.) or Loomis's (Astro- nomy, p. 390), and they are not only simpler but more complete than Baily's (Astronomical Tables, 1827, p. HI), which do not give the cor- * The term 1 — g cos 2 L represents the ratio of the gravity at latitude L°, to the gra- vity at latitude 45°, which on the spheroidal theory of the earth's shape is [1+y. (sin L)»]-5. (1-Hr), and this gives the above value of z. t I have used Airy's formula y — '008668 — l-=-c, and not Biot's where the constant is -00865, 1 -7-c being the compression. Measurements of Arcs. y— -0053273 *=-0026566 •0053252 •0026555 •0054530 •0027191 •0052750 •0026306 •0052816 •0026339 276 Mr. Ellis on the Corrections for Latitude [May 18, rection for the variation of gravity on the vertical. They have the further advantage of being applicable to both English and continental measures. The unavoidable uncertainties of the theory make it useless to consider more minute quantities than a foot, or the hundredth of a metre or of a toise. Hence only five-figure logarithms are required. The following examples will show the use of these Tables. Ex. 1. (Feet and Fahrenheit.) Part of Glaisher's Balloon Ascent, 5th Sept. 1862. (Report of British Association, 1862.) B' 20717 A 32-1 H 9835 V 17-931 a 25-5 L 53 836-0 T 893-6 logB' 1-31633 W. T. G 3754 log 6' 1-25360 H 9885 v for 14000 9 W -06273 V for 10000 -5 logW 879748 h 13643 logT 2-95114 lat. 53°, log G 1-82583 log (W. T. G) 3-57445 Ex. 2. (Metres and Centigrade.) Mont Blanc, taking St. Bernard the lower station. (Ann. Meteorol. de France, 1852.) B' -56803 A' 7-6 Ht 2463 b' -42429 a' -9-1 L 46 500-0 T' 498-5 log B' 9-75437 W. T'. G2 2322 log b' 9-62766 Hj 2463 vl for 4800 3-6 W -12671 V2 for 2400 -0'9 logW 9-10281 A, 4787*7 log T' 2-69767 lat. 46° 1 1-82610 log G2 } 9-73928 log (W. T'. Ga) 3-36586 Ex. 3. (Toises and Centigrade.) Monte Gregorio (cited by Bessel from D'Aubuissori's Geognosie, i. 481). 1865.] and Temperature in Barometric Hypsometry, fyc. 277 B b logB Iog6 t 329-013 263-215 2-51721 2-42848 M' 19-85 m 10-5 A' 19-95 a 9-9 500-0 T' 529-85 Ha L 128-3 46 880-2 128-3 0-3 —o-o 9-35 X -00007 t -00065 logW logT' lat. 46° logG5 i™ s\xr T" a \ 8-94488 W. T'. Gs 2-72415 H2 f 1-826 10 ra for 1000 \9-44946 V2for 100 •08873 •00065 O-O/I/1PLO % i nne.o W -08808 The coefficient 36- 764 in (a) results from Ramond's comparison of tri- gonometrical with barometrical measurements (Mec. Cel. iv. 290). Bessel's theory, with the numbers corrected by Plantamour (Ann. Met6or. de F. 1852), makes it 36-809. If this coefficient were adopted the values of log G in Table II. would have to be increased by -00053. This would increase the results in the foregoing examples by 4 feet, 2*8 metres, and 1-3 toise respectively. Verification of these numbers by actual levelling is much needed, but it is rendered difficult by the uncertainty attending the correction for temperature*. Thus if E = 1 + -003665 . r, where r degrees Centigrade is the temperature of the air at a height of x metres, and X=R1#-;-(R1+a?), it becomes necessary in the determination of the formula to integrate rfX-r-E (see especially Bessel in Schumacher's Astr on. Nachr. vol. xv. no. 356. art. 2. eq. 5), and consequently to know the relation between E and X. Laplace then says (1. c.), " comme les inte- grales ne s'etendent jamais qu'a un intervalle peu considerable, relativement a la hauteur entiere de 1' atmosphere ; toute fonction qui represente a-la-fois les temperatures des deux stations inferieure et superieure, et suivant laquelle la temperature diminue a-peu-pres en progression arithmetique de 1'une a 1'autre, est admissible., et Ton peut choisir celle qui simplifie le plus le calcul." Bessel (I. c.) says " we are entirely ignorant of this relation, and have therefore no reason to assume the alteration of temperature as otherwise than proportional to the alteration of height." Laplace and Bessel then make an assumption which approximatively fulfils this condition and is equivalent to taking E2 + £ . X=a constant, k being determined by the observed temperatures at the two stations. This makes the integration easy, but it is evident that the result should not be applied in cases where the difference of level is not small in relation to the extent of the appreciable atmosphere, or where the temperature does not diminish approximately as the height increases. Now Mr. Glaisher, as the result of his observations * The errors in determining the actual temperatures of the air in mountain ascents, arising from the radiation of the ground, are not considered, because they are rather errors of observation than of theorv. 278 Mr. Ellis on the Corrections for Latitude [May 18, on the diminution of temperature with increase of height, gives a series of average decrements such that on assuming the temperature to decrease m degrees Fahrenheit for an elevation of n thousand feet, and representing a degree Fahrenheit and a thousand feet, hy a horizontal and a vertical unit of length respectively, we shall find that the resulting curve approaches to a rectangular hyperbola mn+am + bn=0, referred to axes parallel to its asymptotes. We may then by the principle of least squares determine the values of a and b from his Tables*. But on comparing such a curve with the curves of alteration of temperature really observed f, the deviation from the average appears so great in particular cases, that no advantage would accrue from complicating the integration by the introduction of such a law. The only course that appears open to pursue is to confine the limits of the integration to those small amounts which Laplace contemplated in the passage cited, and calculate the height by sections. For it also ap- pears from Mr. Glaisher's curve, that for small alterations of height the alteration of temperature varies approximately as the alteration of height, that is, that the curve does not deviate materially from its tangent for com- paratively considerable distances. When the difference of level is many thousand feet the difference of temperature is generally *arge, and the curve consequently differs materially from a straight line. No dependence can then be placed on the result. It would appear that we should be more likely to obtain correct results by dividing the whole height into a number of partial heights, not exceeding 1000 metres or 3000 feet, and taking fresh observations whenever the temperature altered abnormally. To have a rough notion of when this occurs, an aneroid barometer and common thermometer should be watched on the ascent. Mr. Glaisher's observations tend to show that we may expect on an average a fall of very nearly 4° Fahr. for each inch of depression of the barometer under a cloudy sky, the first inch, and the llth to the 16th inch of depression being accompanied by a slightly more rapid fall of temperature. Under a clear or nearly clear sky, there is a fall of about 5° Fahr. for each of the first 4 inches of de- pression of the barometer ; then about 4°-2 per inch from the 5th to the 13th inch, and about 40<5 per inch from the 14th to the 16th inch J. This * In an article in the Reader newspaper (31 Oct. 1863, p. 513), purporting to be an extract from Mr. Glaisher's Keport to the British Association in 1863 (the passage does not occur in the published Eeport of the B. A.), it appears, on correcting two obvious misprints, that he has thus calculated m = 5'6295 . w-=-(l+0'048. «), giving mn+20-8333 . m— 117'281 . «=0, for which mn+ 21w-117«=0 is a sufficiently close approximation, and represents the mean variation very fairly, after the first 5(JOO feet of ascent. t Mr. Glaisher has laid down these in the Proceedings of the British Meteorological Society, vol. i. (19 Nov. 1862) plate 13, with which I have compared the theoretical hyperbola. | These comparisons have been obtained by calculating the height attained for each inch of depression of the barometer, from the 1st to the IGth, taking for the bottom 1865.] and Temperature in Barometric Hypsometry, fyc. 279 may therefore be considered as the normal alteration of temperature. In order to secure simultaneous observations at both stations for each section, it would be necessary to have two ascending parties, one for each variable station, each of which should be able to signal to the other. A stationary observer at the lowest station would serve as a check on the other two. This method introduces many practical difficulties, but the reduction of the observations is rendered very easy by Tables I. and II. The great importance of thus calculating heights by sections will be rendered evident by the following examples. Taking the data in the Ann. Mettor. de F. for 1852, p. 70, we have for Geneva as the lower and St. Bernard as the upper station, L 46, B' 0-72643 A' 8-97 Ht 408, V 0-56364 «' —1-89 Jir 2463. Again, for St. Bernard as the lower and Mont Blanc as the upper station, B' 0-56803 A' 7'6 Hx 2463, V 0-42429 a! — 9'1 Ax 47877; which has been calculated as Ex. 2 above. But taking the data from the Annuaire du B. des L., 1865, p. 324, we have for Geneva as the lower and Mont Blanc as the upper station, B 729-65 M' 18-6 A' 19-3 H, 408, 6 424-05 ml — 4'2 a — 7'6 A, 4815-9. That is, the height of Mont Blanc above the sea, when calculated from observations at Geneva, St. Bernard, and the summit, is determined as 4787" 7 metres, but when calculated from observations at Geneva and the summit only, is determined as 4815-9 metres, or 28*2 metres more. This is striking enough, but it is by no means clear that even the smaller amount may not be too large*. station B' 30, AGO, H 0, L45, and supposing the temperature to decrease according to Mr. G-laisher's Tables. The increase of height for each inch of depression was then divided by the number of feet of ascent in which, according to Mr. Glaisher, the tem- perature falls one degree at the height reached. * In the Ann. Met. de F. (1. c.) M. Plantamour calculates the height of St. Bernard by Bessel's formula (taking account of the humidity of the atmosphere according to his hypothesis, which is, however, not in accordance with Mr. Glaisher's observations) as 2473 metres. In the Annuaire de la Societe Meteorologique de France, 1853, p. 249, M. Plantamour gives the height of the basin of the barometer at the hospice of St. Bernard as 2493 metres, but does not there state how this result was obtained. These heights being respectively 10 and 30 metres greater than that calculated by Laplace's formula, would, if adopted as the height of the lower station in the second calculation, give results more nearly in accordance with those in the third calculation. The object here, however, is to examine the action of Laplace's formula only, and hence the height assumed for St. Bernard must be that due to that formula. But different data give different results for this height. Geneva and St. Bernard are too widely separated horizontally, and have generally too great a difference of temperature, to enable us to calculate the whole height in one section with any degree of confidence, as there are probably many abnormal intermediate changes of temperature which, as will be seen, tend to vitiate the result. Nor can any reliance be placed on adopting the mean barometric pressures and temperatures. If any mean be taken, it mu^t be the mean of many heights separately calculated from their individual data. 280 Mr. Ellis on the Corrections for Latitude [May 18, Mr. Glaisher's balloon ascents offer a very convenient series of examples on account of the comparative closeness of his observations. I have there- fore calculated two, Tables III. and IV., p. 286, which are important from their height or remarkable changes of temperature, first, by determining the height of each station from the lowest (which I call the total method) ; and secondly, by calculating the height of each station from the height of the next lower station (which I call the gradual method). I have added the differences of level between the stations as determined from both methods and the differences between them, which are important for discovering how the discrepancies between the two results are produced by temperature. Each station is lettered. Two letters against a number, as ah 5720, show that the height of the station A above the sea is found as 5720 feet, when station a is taken as the lower station with the height assigned to it in the same column. The distance a A is termed an interval. A careful examination of these results will show that the gradual method is probably the most trustworthy. In Table III. up to station i, both results substantially agree, but in the interval ij there is a sudden increase of temperature, which is quite ab- normal*. The total method, from omitting all considerations of the pre- ceding lower temperatures, makes the height of the interval ij exceed its value as determined by the gradual method by 59 feet, an enormous amount in a total height of 7518 or 7579 feet. The temperature again decreasing from.;' to k, the difference is not so great, but the total method is 8 feet in defect for this interval. Again, for m n there is only a slight fall of tem- perature, and consequently the total method, ignoring the low absolute temperature of the interval, makes the difference of level greater than the gradual method by 27 feet. In pq there is absolutely a rise of tempera- ture, and for the reason last stated, the total method makes the interval 73 feet greater than the gradual. The interval q r is a great contrast to this. The temperature falls very rapidly, 7°'l for a barometric depression of '79 inch, which is nearly double the normal amount as previously de- termined for the 14th inch of depression. Hence the total method, by distributing the cold over the warm parts, makes the interval q r 73 feet less than the gradual method. Again, r s shows an excess of 103 feet in the total method for a steady temperature, and s t a defect of 100 feet for a sudden fall of temperature. Mr. Glaisher's observations show that there was a rise and fall of temperature between r and *, but as there were no simultaneous observations of barometer and thermometer, I have not been able to introduce them into the calculation. The results after r are there- fore very doubtful. The interval v w is liable to grave suspicion, not only from the great length of the interval, but the imperfect manner in which the observations were unavoidably made. Supposing the observations to * It is readily seen that on the assumed law of temperature, E2+£ . X= constant j the sign of dx-i-dt depends on that of k, and is therefore supposed to be constant. Whdn therefore dx~d( alters its sign during part of the height, the Ittw is vitiated, and the formula inapplicable. The only chance of a decent approximation consists in separately calculating the intervals with decreasing and increasing temperatures. 1865.] and Temperature in Barometric Hypsometry, fyc. 281 be correct, the total method makes the interval v w greater than the gra- dual by no less than 610 feet, owing to its distributing the warm tempera- tures over so large an interval of extreme cold. If we then omit the inter- val vw, we find 359 feet for the sum of all the cases in which the total method was in excess of the gradual, and 20 1 feet for the cases of defect, leaving a total excess of 158 feet in 26450 or 26292 feet, which is thus shown to be a very inadequate measure of the degree of uncertainty due to the total method. In Table IV. the results to c, or even d, substantially agree ; but at d the temperature decreases very slowly, and soon becomes absolutely stationary. Great differences immediately appear. From I to r the temperature in- creases, and the total method gains greatly on the gradual till at r it is 541 feet in advance. At stations s, t the total method indicates a de- scent with a falling barometer, whereas the gradual method gives a very slow ascent. Mr. Glaisher's observations show that for the same baro- metric pressure of 14'637 inches, as at r, the temperature varied succes- sively through 36°-l, 38°'2, 38°'l, 42°'2 Fahr., which on the total method indicate different heights, whereas the gradual methods cannot admit any variation of height without a variation of pressure. The rapid fall of the thermometer from u to w causes the total method to give very much smaller intervals than the gradual, but the nearly stationary temperatures of*, y, z turn the balance the other way. On the whole, the total method gives 686 feet in excess, and 335 feet in defect of the gradual method, remaining 351 feet in excess. The temperature varied so abnormally in this ascent that little confidence can be reposed in either result after station h, when the total method is only 32 feet out of 941 1 or 9379 in advance of the gra- dual, which is still a large amount. It may be objected to the gradual method that, by multiplying stations, it multiplies errors of observation. But even when the stations are so un- necessarily multiplied as in Tables III. and IV. (in which nearly every re- corded case of a simultaneous observation of barometer and thermometer has been admitted), the error is not likely to approach that arising from the total method. We may, however, calculate the ascent of Table III. as far as r, beyond which, as already remarked, the variation of temperatures renders the results uncertain, in six instead of sixteen stations, as follows. Abridged Gradual Method. Intervals abridged. Gradual Method. Difference of Level. Abridged less Table III. Abridged. Table III. Abridged. Table III. a ad df f* l;n np pr 490 3655 5017 9875 13633 17552 20339" 490 3655 5019 9885 13640 17559 20357 490 3165 1362 4858 3758 3919 2787 490 3165 1364 4866 . 3755 3919 2798 0 0 - 2 - 8 + 3o -11 282 Mr. Ellis on the Corrections for Latitude [May 18, The final result is 18 feet less than that obtained in Table III. This difference may be easily accounted for. Up toy both results substantially agree. Between / and k there was first a rise and then a fall of tempera- ture, which are overlooked in the abridged calculation, and it consequently loses 8 feet. In the interval p r there was a steady temperature during 1400 feet, which disappears in the abridgement, and consequently it again loses 1 1 feet. It is evident, therefore, that the sections in this abridge- ment have been badly selected, and the importance of determining them rather by change of temperature than by height ascended becomes appa- rent. A better result is obtained by means of the seven sections a i 6327, ij7520,jk 9887, fen 13649, np 17568, pq 18963, qr 20366, deter- mined with reference to the change of temperature. The result, r 20366, is only 9 feet more than that of the gradual method in Table III., but is 104 feet less than that of the total method. If /3, ft', ft" be the barometric readings reduced to 32° F., and a, a', a" the corresponding temperatures of the air for any three stations, then the formula (a) shows that, rejecting the small corrections vv Vlf the height, as determined by the total method, will be the same as that determined by the gradual method when (a + a").(log/3-log/3") = (a + a') . (bg/3-log /3') + («' + «") . (log ft'-log ft"), that is, when a — a' _log/3 — log/3' a'-a" log ft1 -log ft"' When the difference in barometric pressure is not great, and hence ft f/3' is nearly =ft'+ft", by applying the reductions in 'Proceedings,' vol. xii. p. 516, the above condition becomes very nearly, that the decrement of temperature should vary as the decrement of pressure, and this is the case for the normal decrements. Thus in Table III. the intervals a i,j k, lm,np give for the quotients of the decrements of temperature divided by the decrements of pressure 4'635, 4-07, 3*26, 3'92 respectively, and the dif- ferences of the lengths of these intervals, as determined by the total and gradual methods, are only 2, —8, 13, 13 respectively. But for the intervals ij,mn these quotients are — 3'55, 1*27, and the differences 59, 37. Similarly in Table IV., for the intervals a d, ae, ah the quotients are 4 '78, 3-91, 3-97, and the differences —9, 31, 32. These results confirm the above conclusion, and also tend to show that the normal quotient is 4, and to explain why the gradual method is the most generally trustworthy. Since, then, it is advisable to calculate bv such short sections, the prac- tical rules which I gave in a former paper (' Proceedings,' March 26, 1863, vol. xii. pp. 513, 514) may be condensed into one, which will enable any traveller to calculate heights without the assistance of any tables whatever. I conclude this paper, therefore, by annexing it in its improved form, together with a rule calculated on the same principles for foreign data, and an example of each to show the method of working. 1865.] and Temperature in Barometric Hypsometry, §c. 283 PRACTICAL EULES WITHOUT ANY TABLES. 1 . English feet, Fahrenheit temperatures. Multiply the difference of the barometric readings in any unit by 52400, and divide by the sum of the barometric readings. [If the result be 1000, 2000, 3000, 4000, or 5000, add 0, 0, 2, 6, 14 respectively.] Subtract 2 5 times the difference of the temperatures of the mercury. Multiply the remainder by the result of first adding 836 to the sum of the temperatures of the air, next dividing by 900, [and finally adding for latitude 0, 20, 30, 40, 45, and subtracting for lat. 90, 70, 60, 50, 45, the decimals -0026, -0020, -0013, -0005, 0.] To this product add the height of the lower station, [and if the sum is 5000, 10000, 15000, 20000, 25000, add 1, 5, 11, 19, 30, subtracting the same numbers when the upper numbers are the heights of the lower station.] The final result is the height of the upper station above the sea-level according to Laplace's complete formula. [For British heights, the cor- rections in brackets may be omitted.] Fresh observations should be made whenever the temperature does not decrease about 4 degrees for a fall of one inch in the barometer. Calculate great heights in sections. Ex. 4. The same data as Ex. 1, with the exception of H being the interval An in the Table of the 'Abridged Gradual Method.' B' 20717 A 32-1 H 9875 V 17-931 a 25-5 L 53 836-0 B'+S' 38-648 900)893-6 B1— b' 2-786 + 52400 -9929 --0007 for lat. 53° 38-648)145986-400(3777 + 6 p -9922 3754 3783 9875 H + •9922^ +8 for 13000 -5 for 10000 Approximative difference 1 o7- 4 of level J9t A 13632 feet. Since decimals of a foot are rejected, there is always a liability to a dif- ference of 1 or 2 feet between this and the logarithmic method. A difference of 10 feet between this result and that in Ex. 1, is due to the difference in the assumed value of H. [Continued on page 288.] 284 Mr. Ellis on the Corrections for Latitude TABLE I. [May 18, NOTATION (CAPITALS, lower station ; small letters, upper station). B, b units of length of any kind, height of barometer. B', b' the same reduced to 32° Fahr. A, a deg. Fahr., A', a' deg. Cent., A", a" deg. Eeaum., temperature of air. M, m „ ,, M.',m'} „ „ M", m" „ „ temperature of mercury. H, h feet, B^, Ax metres, H2, h2 toises, height above sea. V, v „ V1( vl „ V2, v2 „ correction for height. E „ E! „ E2 „ mean radius of earth. log E=7'3199534, log R^ 6-8039605, log E2=6'5141407. L degrees, mean latitude of the two stations. *=-000039 . (M-m)=-00007 . (W-m') = -000088 . (M"-m"). T=A+a+836; T'=A'+a'+500; T"=A"+a"+400. W=log B— log b-t=log B'— log b'. log G=log 60309-19 -log 900-log (1- -00263 cos2L). log G' =log G+0-25527 log G"=log G+0-35218 log Gx =log G+9-48401-10 log G2=log G+9-73928-10 1 metre =3-28090 feet, 1 toise log G3=log G+9-83619-10 logG4=logG+9-19419-10 log G5=log G+9-44946-10 log G8=log G+9-54637-10 6-39459 feet, 1 toise =1-94904 metres. log 3-28090= -51599, log 6-39459= -80581, log 1-94904= -28982. FOEMUL^E. Result. Feet Temp. Fahr. h =W.T. G +H +v -V „ Cent. =W.T'. G' +H +v - V „ E6aum. =W.T".G"+H +v -V Metres Fahr. A^W.T.Gj+Hj+^-Vj „ Cent. =W.T'.G2+H1+*1-V1 „ Eeaum. =W.T//.G3+H1+v1-V1 Toises Fahr. A2=W.T . G4+H2+v2-V2 „ Cent. =W.T'. G5+H2+t;2-V2 „ E6aum. =W.T".G6+H2+V2-Va Log G is found from the latitude in Table II., without interpolation. V, v ; Vj, v1; V2, v.2 are found from the nearest number of thousand feet, two hundred metres, or hundred toises in H, h, "Kv hv H2, k2 respectively, by Table II., without interpolation. Make fresh observations when the temperature does not decrease about 4° Fahr., or 2° Cent, for a fall in the barometer of 1 inch, or 25 millimetres respectively. 1865.] and Temperature in Barometric Hypsometry, TABLE II. 285 Lat. LogG. Lat. LogG. Feet. Metres. Toises. h, H -flOOO. v, V. *PH, -=-100. «i, Hr *,,H, -hoc. "2,V2. 0° 1-827 28 45° 1-826 14 0 0 0 o-o 0 0-0 1 28 46 10 1 0 2 o-o 1 o-o 2 28 47 06 2 0 4 o-o 2 o-o 3 28 48 1-826 02 3 0 6 o-i •3 o-o 4 27 49 1-825 98 4 1 8 0-1 4 0-1 5 1-827 27 50 94 5 1 10 0-2 5 01 6 26 51 90 6 2 12 0-2 6 0-1 7 25 52 86 7 2 14 0-3 7 0-2 8 24 53 83 8 3 16 0-4 8 0-2 9 23 54 79 9 4 18 0-5 9 0-3 10 1-827 22 55 1-825 75 10 5 20 0-6 10 0-3 11 20 56 71 11 6 22 0-8 11 0-4 12 19 57 68 12 7 24 0-9 12 0-4 13 17 58 64 13 8 26 1-1 13 0-5 14 15 59 61 14 9 28 1-2 14 0-6 15 1-827 13 60 1-825 57 15 11 30 1-4 15 0-7 16 11 61 54 16 12 32 1-6 16 0-8 17 09 62 50 17 14 34 1-8 17 0-9 18 07 63 47 18 16 36 2-0 18 1-0 19 04 64 44 19 17 38 2-3 19 1-1 20 1-827 02 65 1-825 41 20 19 40 2-5 20 1-2 21 1-826 99 66 38 21 21 42 2-8 21 1-4 22 96 67 35 22 ' 23 44 3-0 22 1-5 23 94 68 32 23 25 46 3-3 23 1-6 24 91 69 29 24 28 48 3-6 24 1-8 25 1-826 88 70 1-825 27 25 30 50 39 25 1-9 26 84 71 24 26 32 52 4-3 26 2-0 27 81 72 22 27 35 54 4-6 27 2-2 28 78 73 20 28 38 56 4-9 28 2-4 29 75 74 17 29 40 58 5-3 29 2-6 30 1-826 71 75 1-825 15 30 43 60 5-7 30 2-8 31 68 76 13 31 46 62 6-0 31 2-9 32 64 77 12 32 49 64 6-4 32 3-1 33 61 78 10 33 52 66 6-8 33 3-3 34 57 79 08 34 55 68 7-3 34 3-5 35 1-826 53 80 1-825 07 35 59 70 7-7 35 3-8 36 49 81 06 36 62 72 8-1 36 4-0 37 46 82 04 37 65 74 8-6 37 4-2 38 42 83 03 38 69 76 9-1 38 4-4 39 38 84 03 39 73 78 9-6 39 4-7 40 1-826 34 85 1-825 02 40 77 80 10-1 40 4-9 41 30 86 01 41 80 82 10-6 41 5-2 42 26 87 01 42 84 84 11-1 42 5-4 43 22 88 00 43 89 86 11-6 43 5-7 44 18 89 00 44 93 88 12-2 44 5-9 45 1-826 14 90 1-825 00 45 97 90 12-7 45 6-2 Y 2 286 Mr. Ellis on the Corrections j or Latitude [May i a r-t rt III III S •-< Li X ^ O O •* O O : 'c- 00 O C5 Ct O >S O O ^< t- *M f? OD O ^ O >S >~ O •* — :: — - a. " c-1 l- 0 t^ ^ i-l ci rt ^. i- l- - -M CO O 1865.] and Temperature in Barometric Hypsometry, 6,-e. 287 II I I II I i L^ CO 3 CO § CO 3 i CO 1-H T— i 1 > T£ o t~oo OD < <>1 Cl CT Ol < 288 Mr. Ellis on Barometric Hypsometry. [May 18, 2. French metres, Centigrade temperatures. Multiply the difference of the barometric readings in any unit by 1 6000, and divide by the sum of the barometric readings. If the result be 300, 600, 900, 1200, subtract 0-6, 0-9, 0'9, 0-2; if 1300, 1600, add 0-2, 2-0 respectively. Subtract 1'3 times the difference of the temperatures of the mercury. Multiply the remainder by the result of first adding 500 to the sum of the temperatures of the air, then dividing by 500, and finally adding for latitude 0, 20, 30, 40, 45, and subtracting for lat. 90, 70, 60, 50, 45, the decimals -0026, -0020, -0013, -0005, 0. To this product add the height of the lower station ; and if the sum is 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000 add -2, -6, 1-4, 2-5, 3'9, 57, 77, 10-1, subtracting the same numbers when the upper numbers are the height of the lower station. Fresh observations should be taken whenever the temperature does not decrease about 2° for a fall of 25 millimetres in the barometer. Calculate great heights in sections. Ex. 5. Height of St. Cergues, in the Canton de Yaud, on the road from Paris to Geneva, lat. 46°. (Ann. Meteor, de Fr., 1849, p. 59.) 72971 67673 1406-44 B— b 52-98 X 16000 1406-44)847680-00(602-7 —•9 M'21-5 m1 18-8 2-7 Xl'3 q 3-5 A' 21-8 a' 18-8 500-0 500)540-6 1^408 1-0812 —•0001 lat. 46° p 1-0811 601-8 —3-5 q app. diff. of level 598'3 598-3 X 1-0811^ 646-8 408-0 Hx + •2 for 1000 1055 metres. 1865.] Prof. Thomson on the Elasticity, fyc.t of Metals. 289 IV. "On the Elasticity and Viscosity of Metals." By Prof. W. THOMSON, LL.D., F.R.S., F.R.S.E. Received May 18, 1865. Among the experimental exercises performed by students in the phy- sical laboratory of the University of Glasgow, observations on the elas- ticity of metals have been continued during many years. Numerous ques- tions of great interest, requiring more thorough and accurate investi- gation, have been suggested by these observations ; and recently they have brought to light some very unexpected properties of metallic wires. The results stated in the present communication are, however, with one or two exceptions, due to the careful experimenting of Mr. Donald Macfar- lane, official assistant to the Professor of Natural Philosophy, whose in- terested and skilful cooperation have been most valuable in almost every- thing I have been able to attempt in the way of experimental investigation. The subject has naturally fallen into two divisions, Viscosity, and Moduli of Elasticity. Viscosity. — By induction from a great variety of observed phenomena, we are compelled to conclude that no change of volume or of shape can be produced in any kind of matter without dissipation of energy. Even in dealing with the absolutely perfect elasticity of volume presented by every fluid, and possibly by some solids, as for instance homogeneous crystals, dissipation of energy is an inevitable result of every change of volume, because of the accompanying change of temperature, and con- sequent dissipation of heat by conduction or radiation. The same cause gives rise necessarily to some degree of dissipation in connexion with every change of shape of an elastic solid. But estimates founded on the thermodynamic theory of elastic solids, which I have given elsewhere *, have sufficed to prove that the loss of energy due to this cause is small in comparison with the whole loss of energy which I have observed in many cases of vibration. I have also found, by vibrating a spring alternately in air of ordinary pressure, and in the exhausted receiver of an air-pump, that there is an internal resistance to its motions immensely greater than the resistance of the air. The same conclusion is to be drawn from the observation made by Kupffer in his great work on the elasticity of metals, that his vibrating springs subsided much more rapidly in their vibrations than rigid pendulums supported on knife-edges. The subsidence of vi- brations is probably more rapid in glass than in some of the most elastic metals, as copper, iron, silver, aluminium f ; but it is much more rapid than in glass, marvellously rapid indeed, in some metals (as for instance zinc) £, and in india rubber, and even in homogeneous jellies. * " On the Thermo-elastic Properties of Solids," Quarterly Journal of Mathematics, April 1857. t We have no evidence that the precious metals are more elastic than copper, iron, or brass. One of the new bronze pennies gives quite as clear a ring as a two-shilling silver piece tested in the usual manner. J Torsional vibrations of a weight hung on a zinc wire subside so rapidly, that it 290 Prof. W. Thomson on the Elasticity [May 18, The frictional resistance against change of shape must in every solid be infinitely small when the change of shape is made at an infinitely slow rate, since, if it were finite for an infinitely slow change of shape, there would be infinite rigidity, which we may be sure does not exist in nature*. Hence there is in elastic solids a molecular friction which may be pro- perly called viscosity of solids, because, as being an internal resistance to change of shape depending on the rapidity of the change, it must be classed with fluid molecular friction, which by general consent is called viscosity of fluids. But, at the same time, it ought to be remarked that the word viscosity, as used hitherto by the best writers, when solids or heterogeneous semisolid-semifluid masses are referred to, has not been dis- tinctly applied to molecular friction, especially not to the molecular friction of a highly elastic solid within its limits of high elasticity, but has rather been employed to designate a property of slow continual yielding through very great, or altogether unlimited, extent of change of shape, under the action of continued stress. It is in this sense that Forbes, for instance, has used the word in stating that " Viscous Theory of Glacial Motion" which he demonstrated by his grand observations on glaciers. As, however, he, and many other writers after him, have used the words plasticity and plastic, both with reference to homogeneous solids (such as wax or pitch even though also brittle, soft metals, &c.), and to heterogeneous semisolid-semifluid masses (as mud, moist earth, mortar, glacial ice, &c.), to designate the property f common to all those cases of experiencing, under continued stress, either quite continued and unlimited change of shape, or gradually very great change at a diminishing (asymptotic) rate through infinite time, and as the use of the term plasticity implies no more than does viscosity any physical theory or explanation of the property, the word viscosity is without inconvenience left available for the definition I propose. To investigate the viscosity of metals, I have in the first place taken them in the form of round wires, and have chosen torsional vibrations, after the manner of Coulomb, for observation, as being much the easiest way to arrive at definite results. In every case one end of the wire was attached to a rigid vibrator with sufficient firmness (thorough and smooth soldering I find to be always the best plan when the wire is thick enough) ; has been found scarcely possible to count more than twenty of them in one case experi- mented on. * Those who believe in the existence of indivisible, infinitely strong and infinitely rigid very small bodies (finite atoms !) may deny this. t Some confusion of ideas on the part of writers who have professedly objected to Forbes's theory while really objecting only (and I believe groundlessly) to his usage of the word viscosity, might have been avoided if they had paused to consider that no one physical explanation can hold for those several cases, and that Forbes's theory is merely the proof by observation that glaciers have the property that mud (heterogeneous), mortar (heterogeneous), pitch (homogeneous), water (homogeneous), all have of changing shape indefinitely and continuously under the action of continued stress. 1865.] and Viscosity of Metals. 291 and the other to a fixed rigid body, from which the wire hangs, bearing the vibrator at its lower end. I arranged sets of observations to be made for the separate comparisons of the following classes : — (a) The same wire with different vibrators of equal weights (to give equal stretching-tractions), but different moments of inertia (to test the relation between viscous resistances against motions with different veloci- ties through the same range and under the same stress). (b) The same wire with different vibrators of equal moments of inertia but unequal weights (to test the effect of different longitudinal tractions on the viscous resistance to torsion under circumstances similar in all other respects). (c) The same wire and the same vibrator, but different initial ranges in successive experiments (to test an effect unexpectedly discovered, by which the subsidence of vibrations from any amplitude takes place at very dif- ferent rates according to the immediately previous molecular condition, whether of quiescence or of recurring change of shape through a wider range). (d) Two equal and similar wires, with equal and similar vibrators, one of them kept as continually as possible in a state of vibration, from day to day ; the other kept at rest, except when vibrated in an experiment once a day (to test the effect of continued vibration on the viscosity of a metal). Results. (a) It was found that the loss of energy in a vibration through one range was greater the greater the velocity (within the limits of the experi- ments) ; but the difference between the losses at low and high speeds was much less than it would have been had the resistance been, as Stokes has proved it to be in fluid friction, approximately as the rapidity of the change of shape. The irregularities in the results of the experiments which up to this time I have made, seem to prove that much smaller vibrations (producing less absolute amounts of distortion in the parts of the wires most stressed) must be observed before any simple law of relation between molecular friction and velocity can be discovered. (6) When the weight was increased, the viscosity was always at first much increased ; but then day after day it gradually diminished and be- came as small in amount as it had been with the lighter weight. It has not yet been practicable to continue the experiments long enough in any case to find the limit to this variation. (c) The vibration subsided in aluminium wires much more rapidly from amplitude 20 to amplitude 10, when the initial amplitude was 40, than when it was 20. Thus, with a certain aluminium wire, and vibrator No. 1 (time of vibration one way 1*757 second), in three trials the numbers of vibrations counted were — Vibrations. Vibrations. Vibrations. Subsidence from 40 initial am- ) K r fii R/t plitude to 20 J And from 20 (in course of the 1 9g Q8 96 same experiments) to 10 . . J 292 Prof. W. Thomson on the Elasticity [May 18, The same wire and same vibrator showed — "'vibrations. Again the same wire with vibrator No. 2 * (time of vibration one way 1'236), showed in two trials — Vibrations. Vibrations. Subsidence from 40 initial amplitude 1 ~. -0 to 20 ....................... / And continued from 20 to 10 .. ____ 90 90 Again same wire and vibrator, — From initial amplitude 20 to 10. . 103 vibrations (mean of eight trials). This remarkable result suggested the question («?). (rf) Only one comparison was made. It showed in a wire which was kept vibrating nearly all day, from day to day, after several days, very much more molecular friction than in another kept quiescent except during each experiment. Thus two equal and similar pieces of wire were put up about the 26th of April, hanging with equal and similar lead weights, the tops and bottoms of the two wires being similarly fixed by soldering. No. 2 was more frequently vibrated than No. 1 for a few days at first, but no comparison of viscosities was made till May 15. Then No. 1 subsided from 20 initial range to 10 in 97 vibrations. No. 2, the same subsidence in 77 vibrations. During the greater part of May 16 and 17, No. 2 was kept vibrating, and No. 1 quiescent, and late on May 17 experiments with the following results were made : — Time per vibration. No. 1. Subsided from 20 to 10 after 99 vibrations in 237 seconds . 2*4 98 235 „ „ 98 235 No. 2. Subsided from 20 to 10 after 58 142 „ n „ 60 147 57 139 60 147 .2-4 2-4 2-45 2-45 2'45 2-45 [Addition, May 27, since the reading of the paper.] — No. 1 has been kept at rest from May 1 7, while No. 2 has been kept oscillating more or less every day, till yesterday, May 26, when both were oscillated, with the following results : — Time per vibration. No. 1. Subsided from 20 to 10 after 100 vibrations in 242 seconds 2-42 „ 2. „ „ 44 or 45 vibrations 2-495 Moduli of Elasticity. — A modulus of elasticity is the number by which the amount of any specified stress, or component of a stress, must be divided to find the strain, or any stated component of the strain, which it produces. Thus the cubic compressibility of water being a-y^ny per atmosphere, its "modulus of compressibility" or its "volume modulus of elasticity," is 21000 atmospheres, or 76 x 13-596 x 21000=21'7 X 10" grammes weight * Of same weight as No. 1, but different moment of inertia. 1865.] and Viscosity of Metals. 293 per square centimetre (as 13'596 is the density or specific gravity* of mer- cury, and 76 centimetres the height of the barometric column corresponding to the pressure defined as "one atmosphere"). Or, again, Young's "modulus," which has generally been called simply the modulus of elasticity of a solid, is the longitudinal traction of a stretched rod or wire of the sub- stance, divided by the extension produced by it. Or, lastly, the " modulus of rigidity," or, as it is conveniently called, simply " the rigidity " of an iso- tropic solid, is the amount of tangential stress divided T by the deformation it produces, — the former being mea- sured in units of force per unit of area applied, as shown in the diagram, to each of four faces of a cube, and the latter by the variation of each of the four right angles, reckoned in circular measure. Measurements of Young's modulus have been made for many bodies by many experimenters; but hitherto there have been very few determinations of rigidity, notwithstanding the great ease with which this can be done for wires by Coulomb's method. Accordingly, although several accurate determinations of Young's modulus have been made upon wires of different substances hung in the College Tower of the University of Glasgow (which, by giving 80 feet of clear protected vertical space, affords great facilities for the investigation), I shall in this paper only refer to some of the results as bearing on the question, how are moduli of elasticity affected in one substance by permanent changes in its molecular condition ? which was my starting- point for all I have attempted to do experimentally regarding the elasticity of solids. To determine rigidities by torsional vibrations, taking advantage of an obvious but most valuable suggestion made to me by Dr. Joule, I used as vibrator in each case a thin cylinder of sheet brass, turned true outside and * The one great advantage of the French metrical system is, that the mass of the unit volume (1 centimetre) of water at its temperature of maximnm density (3°-945 Cent.) is unity (1 gramme) to a sufficient degree of approximation for almost all practical purposes. Thus, according to this system, the density of a body and its specific gravity mean one and the same thing ; whereas on the British no-system the density is expressed by a number found by multiplying the specific gravity by one number or another, according to the choice (of a cubic inch, cubic foot, cubic yard, or cubic mile) that is made for the unit of volume, and the weight of a grain, scruple, gun-maker's drachm, apothecary's drachm, ounce Troy, ounce avoirdupois, pound Troy, pound avoirdupois, stone (Imperial, Ayr- shire, Lanarkshire, Dumbartonshire), stone for hay, "stone for corn, quarter (of a hundred- weight), quarter (of corn), hundredweight, or ton, that is chosen for unit of force. It is a remarkable phenomenon, belonging rather to moral and social than to physical science, that a people tending naturally to be regulated by common sense should voluntarily con- demn themselves, as the British have so long done, to unnecessary hard labour in every action of common business or scientific work related to measurement, from which all the other nations of Europe have emancipated themselves. I have been informed, through the kindness of Professor W. II. Miller, of Cambridge, that he concludes, from a very trustworthy comparison of standards by Kupffer, of St. Petersburgh, that the weight of a cubic decimetre of water at temperature of maximum density is 1000-013 grammes. 294 Prof. W. Thomson on the Elasticity [May 18, inside (of which the radius of gyration must be, to a very close degree of approximation, the arithmetic mean of the radii of the outer and inner cylindrical surfaces), supported by a thin flat rectangular bar, of which the square of the radius of gyration is one-third of the square of the distance from the centre to the corners. The wire to be tested passed perpendicu- larly through a hole in the middle of the bar, and was there firmly soldered. The cylinder was tied to the horizontal bar by light silk threads, so as to hang with its axis vertical. The following particulars show the dimensions of the vibrators of this kind which I have used. Moment of Cylinders. Outer diameter. Inner diameter. Mean radius. Weight in grammes. inertia round axis in gramme- centimetres. No. 1 15-3 centims. 14'8 centims. 7-525 527-92 29894 , 2 15-3 14-8 „ 7-525 523-45 29641 , 3 10-295 , 9'79 „ 5-021 360-54 9089 , 4 10-3 9-81 „ 5-027 726-40 18357 , 5 10-25 , 9-745 „ 4-999 718-36 17952 > 6 10-295 , 9-805 „ 5-025 342-45 8647 Length. Breadth. Weight. Moment of inertia round axis through middle, perpendi- cular to length and breadth. Bar 1 » 2 24-03 centims. 24-11 „ •965 centim. •95 38-955 grms. 46-68 „ 1877-5 2255-5 Towards carrying out the chief object of the investigation, each wire, after having been suspended and stretched with just force enough to make it as nearly straight as was necessary for accuracy, was vibrated. Then it was stretched by hand (applied to the cross bar soldered to its lower end) and vibrated again, stretched again and vibrated again, and so till it broke. The results, as shown in the following Table, were most surprising. Length of wire, in centime- tres, Volume, in cubic cen- timetres, Density. Moment of inertia of vibrator, Time of vibration one way (or half- period), Rigidity, in grammes weight per square centimetre, Substances. V. Wfc2. in seconds, 27r3/3\VA:2 I. T, g-T^V2 ' 60-3 1-1845 2-764 31771 1-14 241X106 Aluminium •. 304-9 2-351 7-105 31896 4-31 359-6 XlO6 Zincb. 237*7 4-76 410-3 XlO6 248-3 5-456 354-8 XlO6 " Remarks. a Only forty vibrations from initial arc of convenient amplitude could be counted. Had been stretched considerably before this experiment. b So viscous that only twenty vibrations could be counted. Broke in stretching. 1865.] and Viscosity of Metals. TABLE {continued). 295 Length of wire, in centime- tres, Volume, in cubic cen- timetres, V. Density. Moment inertia of vibrator, Time of vibration one way (or half- period), in seconds Rigidity, in grammes weight per square centimetre, Substances. T. g T2V2 261-9 2435-0 214-4 143-7 286-8 1-703 15-30 1-348 •9096 8-398 8-91 8-864 8-674 38186 61412 31771 61412 swill 5-96 16-375 20-77 5-015 6-982 3-381 4-245 350-1 XlO6 448-7 XlO6 448-4 XlO6 433-0 XlO6 431-8 XlO6 393-4 XlO6 442-9 XlO6 Brass. Copper. Copper c. Copper d. Copper*. 291 4-375 435-6 XlO6 293 " 4-417 436-2 XlO6 " 296-1 SOO'O H 4-500 4-588 433-8 XlO6 434-0 XlO6 » 303-4 " 4-646 437-8 XlO6 " 309'3 " 4-833 428-6 XlO6 " 313-2 " 4-931 427-5 XlO6 " 317-4 215-6 1-962 8-835 31771 5-040 8-155 425-9 XlO6 44 2-3 XlO6 Copper f. 235-5 251-9 253-2 - 262-8 '•827 1-580 8-872 8-91 9-425 10-463 5-285 5-640 432-2 XlO6 428-6 XlO6 472-9 XlO6 464-3 XlO6 Copper8- 270-4 5-910 460-4 XlO6 278-7 6-20 458-5 X 106 287-9 6-5325 455-0 XlO6 297-5 6-8195 451'OxlO6 " 308-8 7-3075 448-9 XlO6 " 256-5 267-9 1-6145 8-90 4-226 4-5625 463-5 XlO6 453-3 XlO5 Copper11. 280-1 4-915 446-2 XlO6 " 292-2 5-240 445-5 XlO6 " 301-9 5-532 438-2 XlO6 " 316-8 6-655 791-4X106 Soft iron '. 322-1 6-88 778-3 XlO6 335-1 7-301 779-0 XlO6 " 347-4 7-768 766-6 XlO6 " 366-0 39-4 65-9 75-7 1-357 •1745 •1825 •1185 7-657 20-805 19-8 10-21 206'i2 10902 10967 8-455 2-05 756-0 XlO6 622-25 XlO6 281 X 106 270 XlO6 Platinum k. Gold1. Silver '. Remarks. c A piece of the preceding stretched. d The preceding made red-hot in a crucible filled with powdered charcoal and allowed to cool slowly, became very brittle : a part of it with difficulty saved for the ex- periment. e Another piece of the long (2435 centims.) wire ; stretched by successive simple tractions. f A finer-gauge copper wire; stretched by successive tractions. B Old copper wire, softened by being heated to redness and plunged in water. A Iengthof260centims.cutfromthis,suspended, and elongated by successive tractions. h Another length of 260 centims. cut from the same and similarly treated. 1 One piece, successively elongated by simple tractions till it broke. k Not stretched yet for a second experiment. 1 Added, May 27, after the reading of the paper. 29G On the Elasticity and Viscosity of Metals. [May 18, Thus it appears that that specific rigidity which is concerned in torsion is very markedly diminished in copper, brass, and iron wire when the wire is elongated permanently by a simple longitudinal traction. "When I first observed indications of this result, I suspected that the diminution in the torsional rigidity on the whole length of the wire might be due to inequali- ties in its normal section produced by the stretching. To test this, I cut the wire into several pieces after each series of experiments, and weighed the pieces separately. The result proved that in no case were there any such inequalities in the gauge of the wire in different parts as could possi- bly account for the diminution in the torsional rigidity of the whole, which was thus proved to be due to a real diminution in the specific rigidity of the substance. The following sets of weighings, for the cases of the wires of the two last series of experiments on copper, may suffice for example : — Wire of 308-8 centims. long, cut into four pieces. Length, in centimetres. Weight, in grammes. Weight per centimetre, in grammes. No. 1 „ 2 „ 3 „ 4 109-2 667 63-2 69-4 5-023 3-050 2-865 3-143 •04600 •04573 •04533 •04517 308-5 14-081 Wire of 301 '9 when last vibrated; further elongated by about 8 centi- metres, when it broke ; then cut into five pieces in all. Length, in centimetres. Weight, in grammes. Weight per centimetre, in grammes. No. 1 66-3 3-183 •04801 „ 2 66-4 3-083 •04643 „ 3 66-5 3-039 •04570 „ 4 66-8 3-072 •04599 „ 5 43-4 1-986 •04576 By several determinations of observations on the elongations within the limits of elasticity produced by hanging weights on long wires (about 80 feet) suspended in the College tower, it seemed that Young's modulus was not nearly so much (if at all sensibly) altered by the change of molecular condition so largely affecting the rigidity ; but this question requires fur- ther investigation. The amount of the Young's modulus thus found was, in grammes weight per square centimetre, 1159 X 108 for one copper wire, and 1153x 106 for another which had been very differently treated. 1865.] Prof. W. H. Miller on Two New Forms of Heliotrope. 297 The highest and lowest rigidities which I have found for copper (extracted from the preceding Table) are as follows : — Highest rigidity, 473X106, being that of a wire which had been softened by heating it to redness and plunging it into water, and which was found to be of density 8*91. Lowest rigidity 393-4 x 106, being that of a wire which had been rendered so brittle by heating it to redness surrounded by powdered charcoal in a crucible and letting it cool very slowly, that it could scarcely be touched without breaking it, and which had been found to be reduced in density by this process to as low as 8*674. The wires used were all commercial specimens — those of copper being all, or nearly all, cut from hanks supplied by the Gutta Percha Company, having been selected as of high electric conductivity, and of good mechanical quality, for submarine cables. It ought to be remarked that the change of molecular condition pro- duced by permanently stretching a wire or solid cylinder of metal is cer- tainly a change from a condition which, if originally isotropic, becomes seolotropic* as to some qualities f, and that the changed conditions may therefore be presumed to be seolotropic as to elasticity. If so, the rigidities corresponding to the direct and diagonal distortions (indicated by No. 1 and No. 2 in the sketch) must in all probability become different from one another when a wire is permanently stretched, instead of being equal as they must be when its substance is isotropic. It becomes, therefore, a question of extreme interest to find whether rigidity No. 2 is not increased by this process, which, as is proved by the experiments above described, diminishes, to a very remarkable degree, the rigidity No. 1 . The most obvious ex- periment, and indeed the only practicable experi- ment, adapted to answer this question, will require an accurate determination of the difference produced in the volume of a wire by applying and removing longitudinal traction within its limits of elasticity. With the requisite ap- paratus a most important and interesting investigation might thus be made. V. " On Two New Forms of Heliotrope." By W. H. MILLER, M.A., For. Sec. R.S., and Professor of Mineralogy in the Uni- versity of Cambridge. Received May 17, 1865. A heliotrope is a mirror O provided with some contrivance for adjusting it so that any given distant point T may receive the light of the sun S * A term introduced to designate a substance which has varieties of property in various directions (Thomson and Tait's ' Natural Philosophy,' § 676). t See, for example, a paper by the author, " On Electrodynamic Qualities of Metals," Philosophical Transactions, 1856. l&Jt 298 Prof. "VV. H. Miller on Two New Forms of Heliotrope. [May 18, reflected from the surface of the mirror. This instrument has been con- structed on three different principles. In Drummond's (Philosophical Transactions for 1826, p. 324), by a simple mechanism, a normal to the mirror is made to bisect the angle between the axes of two telescopes, one of which is pointed to T, and the other to S ; consequently T will receive the light of S reflected from O. In Struve's (Breitengradmessung, p. 49) the mirror is directed by means of two sights attached to its support, which are brought into the line OT. The heliotrope employed in the Ordnance Survey (Ordnance Trigonometrical Survey of Great Britain and Ireland, Account of Observations and Calculations of the Principal Tri- angles, p. 47) is similar to Struve's, except that a single mark placed at a convenient distance in the line OT is substituted for the two sights. In the two heliotropes invented by Gauss (Astronomische Nachrichten, vol. v. p. 329, and v. Zach's Correspondance Astronomique, vol. v. p. 374, and vol. vi. p. 65), in Steinheil's (Schumacher's Jahrbuch fur 1844, p. 12), and in Gallon's an optical contrivance is connected with the mirror, so as to throw a cone of sunlight in a direction opposite to the cone of sunlight reflected from the surface of the mirror, the axes of the two cones being parallel, and either very nearly or absolutely coincident. Hence any point T, from which a portion of the former cone of light appears to proceed, •will receive the light of the sun reflected from the mirror. The heliotropes I am about to describe produce two cones of sunlight thrown in opposite directions, like those of Gauss, Steinheil, and Gallon, but differ from them in having no moveable parts, and from all but Gallon's, and the sextant-heliotrope of Gauss, with a second moveable mirror, in requiring no support except the hand of the operator. One of these consists of a plane mirror, to an edge of which are attached two very small plane reflectors, a, c, forming with one another a reentrant angle of 90°, and making angles of 90° with the faces of the mirror. If a ray be reflected once by each of the two planes a, c, it is obvious that the first and last directions of the ray will be parallel to a plane containing the intersection of a, c, and will make equal angles with the intersection of a, c, which is also a normal to the face of the mirror. Therefore, if two parallel rays fall, one on the mirror, and one on either of the planes a, c, the direction of the ray reflected from the mirror will be parallel and opposite to that of a ray reflected once at each of the planes a, c. When the small reflectors are made of bits of unsilvered glass, the brightness of the image of the sun is so far reduced after the second reflexion, as not to interfere with the direct vision of T, and the mirror can be pointed without difficulty. The other consists of a plate of glass having parallel faces b, d, with two polished plane faces a, c on its edges, making right angles with one another, and with the faces b, d, the face d being silvered, with the excep- tion of a portion at the angle adc not larger than the pupil of the eye. It is easily seen that if a ray of light incident upon b, and refracted 1865.] Prof. W. H. Miller on Two New Forms of Heliotrope. 299 through b, so as to be reflected internally once at each of the planes a, c, emerge through d, the planes of incidence and emergence will be parallel, and the incident and emergent rays will make equal angles with the edge ac, and therefore with a normal to the faces b, d. Hence the portion of the incident ray which is reflected from the mirror will proceed in a direction parallel and opposite to that portion of the ray which, after internal reflexion at a and c, emerges through d. In order to ascertain that the construction of such an instrument pre- sented no unforeseen difficulties, I requested Mr. T. E. Butters, of 4, Crescent, Belvedere Road, the well-known maker of sextant-mirrors and artificial horizons, to form the faces a, c on the edges of a piece of plate glass, and then had the face d coated with chemically reduced silver. Upon trial, the emergent light was found to be too bright; but after smoking the angle adc in the flame of a candle, in order to reduce the intensity of the light, it became perfectly easy to make the centre of the image of the sun coincide with the object T seen by direct vision. An image of the sun of suitable intensity for pointing might be obtained by attaching to the edge of the mirror a piece of tinted glass, of the form of the corner abed, with the faces b, d parallel to the plane of the mirror. The Society then adjourned, over the Whitsuntide Recess, to Thursday, June 1 5, the President having announced the Meeting for the Election of Fellows to take place on Thursday, June 1, at 4 P.M. June 1, 1865. The Annual Meeting for the election of Fellows was held this day, Major-General SABINE, President, in the Chair. The Statutes relating to the Election of Fellows having been read, Mr. Brayley and Dr. Webster were, with the consent of the Society, nominated Scrutators to assist the Secretaries in examining the Lists. The votes of the Fellows present having been collected, the following Candidates were declared to be duly elected into the Society. The Hon. James Cockle, M.A. Rev. William Rutter Dawes. Archibald Geikie, Esq. George Gore, Esq. Robert Grant, Esq., M.A. George Robert Gray, Esq. George Harley, M.D. Fleeming Jenkin, Esq. William Huggins, Esq. Sir F. Leopold McClintock, Capt. R.N. Robert McDonnell, M.D. William Kitchen Parker, Esq. Alfred Tennyson, Esq., D.C.L. George Henry Kendrick Thwaites, Esq. Lieut.-Col. James Thomas Walker, R.E. 300 Communication to the Board of Trade ^ [June, Communication from the President and Council of the Royal Society to he Board of Trade on the subject of the Magnetism of Ships*. " To the Right Hon. Thomas Milner Gibson, President of the Board of Trade. "The Koyal Society, May 18, 1865. " SIR, — The attention of the Fellows of the Royal Society has been re- cently directed to the very great increase which has taken place in the employment of iron in the construction and equipment of ships, and the consequent augmentation of the embarrassment occasioned in their naviga- tion by the action of the ship's magnetism on their compasses. " The inconveniences which have already made themselves felt in the ships of the mercantile marine, and which threaten to be productive of very serious loss of life and property, unless remedial measures be adopted similar to those which have proved so advantageous to the ships of Her Majesty's Navy, have induced the President and Council of the Royal Society, after much consideration, to venture on the step of calling your attention, as presiding over the Department of Trade, to a subject which they believe to be of pressing importance. "In this view the accompanying Memorandum has been prepared, stating, as briefly as may be, the particulars which they are desirous of bringing under your consideration ; in the belief that the time has fully arrived when measures of a more stringent and eifectual character are required, in the direction which has-been already taken by Her Majesty's Government in such legislative enactments as those contained in the Merchant Shipping Act (1854), adverted to in the accompanying Memo- randum. " I have only to add that it would afford the President and Council great satisfaction if they could be of any further assistance in a matter which they believe to be of so much importance. " I have the honour to be, " Your obedient Servant, "EDWARD SABINE, " President of the Royal Society." "Memorandum. • " It is believed that the time has come when it is expedient that the Executive Government should exercise a more direct and systematic super- vision over the adjustment of the compasses of ships of the mercantile marine than it has hitherto done. The opinion that it might do so with advantage is not new, as may be seen from passages in the 2nd and 3rd Reports of the Liverpool Compass Committee (2nd Report, p. 30 ; 3rd Report, p. 38), but it has of late been gaining strength from the following among other circumstances : — * Published in the Proceedings, by order of the Council. 1865.] on the Magnetism of Ships. 301 "(1) The great increase in the number of iron ships, as well as in the amount of iron used in the construction of such ships. " (2) The losses of iron ships. " (3) The advances which have been made in, and the present state of, the science of the deviation of the compass. " We may consider these separately. " I . It is believed that for some years the number of iron ships con- structed has greatly exceeded that of wood-built ships, and this is particu- larly the case as regards passenger steamers. In such vessels iron is now used not only in the construction of the hull but in decks, deck-houses, masts, rigging, and many other parts of the ship for which wood was till recently used. The consequence has been a great increase in the amount of the deviation of the compass, increased difficulty in finding a proper place for the compass, and increased necessity for, and difficulty in, apply- ing to the deviation either mechanical or tabular corrections. " 2. Many recent losses of iron steamers have taken place, in which it is probable that compass-error has occasioned the loss. In most of these, how- ever, from the want of any record of the magnetic state of the ship, of the amount of original deviation, and of the mode of correction, and from the investigations into the causes of the loss being conducted by persons not instructed in the science, and who are necessarily incompetent either to elicit the facts from which a judgment can be formed, or to form a judg- ment on those facts which are elicited, no certain conclusion as to the cause of loss can be arrived at. The investigations are, however, suffi- cient to show the want of a better and more uniform system of compass- correction in the mercantile marine, and of more knowledge of the subject among masters and mates. " 3. Since the first introduction of iron ships it has been a recognized fact that they cannot be safely navigated without the compass being as it is termed ' adjusted,' t. e. without the deviations being corrected either mechanically by magnets or by a table of errors ; but at first the correc- tion of each ship was a separate and independent problem. Now the case is different. The theory of the deviation, its causes, and its laws, are now thoroughly understood and reduced to simple formulae, leaving the nume- rical magnitude of a certain small number of quantities to be determined by observation for each ship separately; and further, by recording, re- ducing, and discussing the deviations which have been observed in the ships of the Royal Navy of different classes, numerical results, as to the values of these quantities in ships of each class, have been determined which promise to be of the greatest use in facilitating the complete deter- mination of the deviation and its correction, and in suggesting modes for constructing iron ships, and in the selection of the position of the standard compass. The science of magnetism, in its relation to navigation, is, in fact, in a position in some degree analogous to that in which the science of astronomy at one time was. The principles of the science have been z2 '302 Communications to the Board of Trade [June, established, the formulae have been obtained ; but numerical values are wanted, which can only be derived from a large number of observations systematically made and discussed. At present these numerical results have only been obtained from, and are only applicable to, the ships of the Royal Navy. Without some systematic direction, the mercantile marine can neither derive the full benefit of, or contribute its due share to, the advance of the science. " That the subject is one coming properly within the cognizance of the Board of Trade may be inferred from the Legislature having already in the Merchant Shipping Act, 1854, sect. 301, art. (2), provided that 'every sea-going steamship employed to carry passengers shall have her com- passes properly adjusted from time to time, such adjustment to be made to the satisfaction of the Shipwright Surveyor, and according to such regulations as may be issued by the Board of Trade.' The Shipwright Surveyor is then (sect. 309) to make a ' declaration ' that the f compasses are such and in such condition as required by the Act,' and on such ' de- claration ' the ' certificate ' of the Board of Trade is issued. " It does not appear how these enactments are construed or carried into effect. It is not, however, understood that the Shipright Surveyor is expected or is necessarily competent to do more than see that the ship is furnished with proper compasses, but the goodness of the compass has nothing to do with the deviation ; the best compasses are affected by the deviation precisely in the same way and to the same extent as the worst*. It is not understood that he exercises any judgment or control as to the position of the compass, the amount of deviation, or the mode of adjust- ment, or any of the various points which are involved in the compass being ' properly adjusted.' *' As regards the important subject of ' deviation,' all that has been done by the Board of Trade consists, it is believed, in the publication of the ' Circular on Deviation ' compiled by Admiral FitzRoy, the publication of the Reports of the Liverpool Compass Committee, and the publication of ' Practical Information for Masters and Mates,' by Mr. Towson. "As regards the particular points to which the attention of the Board of Trade may be invited, they may be considered under the following heads: — " (1) The correction of the compass in particular ships. " (2) The advancement of the science of deviation of the compass. " (3) The education of Masters and Mates. " 1 . As before observed, it is now recognized that every iron ship must have its compasses ' adjusted.' Hitherto two totally different modes of * This is subject to the qualification that, from the diminution of directive force in ships having large deviations, compasses of superior power and delicacy are required ; and if the compasses arc corrected by magnets, a particular arrangement of needles is requisite. 1865.] on the Magnetism of Ships. 303 adjustment have been practised, each of which lias its advantages and disadvantages. " i . The system recommended by a Committee of Men of Science and Naval Officers appointed by the Admiralty in 1837, and which has been uniformly followed in the Royal Navy from that time. In this system each ship has a ' Standard Compass,' distinct from the Steering-Compass, fixed in a position selected, not for the convenience of the steersman, but for the moderate and uniform amount of the deviation at and around it. The ship is navigated solely by that compass. The deviation of that compass on each course is ascertained by the process of ' swinging' the ship ; a table of deviation is formed, and the deviations given by the tables are applied as corrections to the courses steered. " 2. The system proposed by the Astronomer Royal in 1839, and which is understood to be generally followed in the mercantile marine. In this system the deviations of the compass are compensated by magnets (and occasionally soft iron). The ship is navigated by the compass so cor- rected— generally the steering-compass, and generally without any tabular correction. " It would not be right, considering the weight of authority on each side, to pronounce any decided opinion against either of those modes of correction when properly used. The first system has proved in the Royal Navy to be one which can be used without danger. The same cannot be said of the second method as regards the mercantile marine ; but the prin- cipal danger of the method arises from what is in truth an abuse of the method : it is that, in reliance on the power of correcting any amount of original deviation, however great, the navigating-compass is placed in a position in which the original deviations are excessive and vary rapidly, and in which no navigating-compass should be placed. " In merchant ships the most convenient place for the steering-compass is generally near the upper part of the stern-post, the rudder-head, the tiller, and the iron spindle of the steering-wheel — all, from their shape and position, powerfully magnetic. The constructor and owner, for the sake of economy, desire that the steering-compass should be the navigating-com- pass. The compass-adjuster fears that any objection on his part would be considered a confession of incompetence, and that some less scrupulous adjuster would not hesitate to undertake the correction. The correction can only be made by powerful magnets. The compass is then held, as it were, in equilibrium by powerful antagonistic force ; and when the changes take place, which it is known do take place in all new iron ships, or when any changes take place in the magnets, large errors are introduced, which are the more fatal because the shipmaster is taught to believe that his compass is correct. " This abuse of the method is one the temptation to which is unfortu- nately so strong, that it is believed it can only be effectually prevented by prohibiting the use of the steering-compass as the navigating-compass, or 604 Communication to the Board oj Trade [June, rather by requiring that the ship shall have a navigating-compass distinct from, and in addition to, the steering-compass. " It is therefore recommended that every iron passenger-ship should be required to have a standard compass distinct from the steering-compass in a selected situation at a certain distance from all masses of iron ; that, whether corrected or not, the original deviations of the standard compass should not in ordinary cases exceed a certain limited amount ; and that on each occasion of the compass being adjusted, a table of the deviations should be furnished to the Master and returned to the Board of Trade ; and that if corrected by magnets, a return should be made of the position of the magnets and of every subsequent alteration of their position. Pro- vision may be made for exceptional cases, in which it may be found im- practicable to place the standard compass in a position where the original deviation is within the limit, by requiring in such cases a special certificate from the central authority. " It may be here observed, as regards many practical matters connected with the adjustment of the compass in particular ships, in which at present great diversity of practice prevails, that an organized department under a skilful superintendent in constant communication with the ports, would probably be of the greatest service, not merely in laying down rules, but in giving advice and suggestions to naval constructors, compass-makers and adjusters, and producing a uniform system of adjustment at the different ports, which would be generally understood by shipmasters. Advice from the same source would be not less useful to the authorities in the different ports in suggesting means of facilitating the adjustment by meridian-marks on shore, laying down moorings, &c. It would probably be one of the first duties of the superintendent of such a department to acquaint himself thoroughly with the methods practised at the different ports, and to give such suggestions, either in the form of reports to the Board of Trade, or in private communications, or both, as might appear to him advisable. Such a superintendent would also be available as an assessor in investigations into the loss of iron vessels, in cases in which there is any possibility of the loss having been occasioned by compass-error. " 2. The advancement of the science of the Deviation of the Compass. " Whatever difference of opinion exists as to the advantage or necessity of a Standard Compass as regards the safety of particular ships, there is none as to its being indispensable for any scientific inquiry into the amount of the deviation and of its constituent parts and its changes. It is from the Tables of the deviation of such compasses, and such compasses alone, observed at different times and places, and systematically reduced and dis- cussed, that those numerical results can be obtained which promise to be so useful in securing in iron ships a place for the Standard Compass where the deviation is of a safe and manageable amount, and in guarding against the dangers which arise from changes in the magnetism of recently built ships. It is from the recorded deviations of such compasses that on the loss of a 1865.] on the Magnetism of Ships. 305 ship a judgment may be formed of the effect of the deviation in causing any error in the course of the ship. "3. The education of Masters and Mates. " At present it may be said that entire ignorance of the subject is the rule. " The subject has not hitherto been a recognized branch of the educa- tion of the seaman ; and the most skilful seamen frequently either ignore it altogether, or look upon it as a mystery not capable of comprehension. Now, however, that the principles of the science have been established, it is found that the subject is not one of any serious difficulty ; and although it might not be considered just to require Masters and Mates already certifi- cated to pass an examination in a new subject, yet an opportunity might be given them of passing a voluntary examination ; and as regards future Can- didates for a Certificate of competence, notice might be given that after a certain period, say two or three years, a certain amount of knowledge of the subject will be required from Candidates (and in the mean time a text-book containing the necessary amount of information might be prepared and published), and the Examiners of the Local Marine Boards will themselves receive instruction, and, if necessary, undergo an examination on the subject. " For the purposes indicated, it seems desirable to establish a department of the Board of Trade under a competent Superintendent, the whole, or greatest part of whose time should be devoted to this subject. Almost all the advances which have hitherto been made in the science, and which have placed England at the head of the science, are due to there having been for the last twenty-five years one Officer charged by the Admiralty with this duty almost exclusively. Such an Officer becomes the depositary of all that is known on the subject, and has no difficulty in obtaining the best scientific assistance. It seems desirable that for some years at least the Board of Trade should take advantage of the ability and experience of the present Superintendent of the Compass Department of the Navy. It is understood that there would be no practical difficulty, and there would be many advantages in the present state of the science in having the superintendence of the compasses of the Royal and Mercantile Marine united in one head, with competent assistants in the two branches of the service. The subject, as has been observed, is not one of difficulty. Any intelligent man could speedily be instructed in all that would be necessary to enable him to discharge the duties of Assistant for the Mercantile Marine ; and in the selection of such an Assistant, probably it would be more important to look to general ability, intelligence, docility, and the habit of, and aptitude for, dealing with men, and particularly with Masters of merchant vessels, than to any previous knowledge of the subject." 306 Correspondence with the Board of Trade [June, Correspondence between the Board of Trade and the Royal Society in reference to the Meteorological Department*. From T. H. Farrer, Esq., Marine Secretary of the Board of Trade, to General Sabine. "Board of Trade, Whitehall, 26 May, 1865. " SIR, — I am directed by the Lords of the Committee of Privy Council for Trade, on the occasion of the vacancy in the Office of Chief of their Meteorological Department, caused by the untimely death of Admiral FitzRoy, to request you to be so good as to bring under the notice of the President and Council of the Royal Society the correspondence which took place between that Society and this Office at the time of the institu- tion of the Meteorological Department as a branch of this Office ; and particularly your letter of the 22nd February, 1855f, in reply to that from this Office of the 3rd of June, 1854, in which, when about to institute the Department, My Lords had desired the opinion of the Royal Society as to what were the great desiderata in Meteorological Science. The recom- mendations of the Royal Society conveyed in your letter of the 22nd of February, 1855, were adopted as the basis of the proceedings of the Me- teorological Department ; instruments were provided, logs were prepared, furnished, and returned to the office, and some progress was made in carrying into effect the original programme. "But in 1859 or 1860, the French Government having adopted a system of telegraphing and publishing the actual state of weather from one place to another, cooperation in which was urged on the Board of Trade by a Committee of the British Association and by Admiral Fitz- Roy, My Lords gave their sanction to what was proposed, and thence- forward a considerable part of the vote previously applied to obtaining and digesting observations was diverted to these Telegrams. In 1861 Admiral FitzRoy grafted on this system of telegraphic communication a system of forecasting the weather (the forecasts being published in the daily papers), and, on occasions of anticipated storms, the giving of special warnings, communicated by telegraph to the different Ports, and there made known by hoisting certain signals. The whole, or almost the whole, of the Funds originally voted for the purpose of observations were thus diverted from their original scientific object to an object deemed more im- mediately practical. " In 1863, on the occasion of an increased estimate for the purpose of these forecasts, it was determined to compare the forecasts and the warn- ings with the actual results. " As regards the daily forecasts, the daily reports of weather published by Admiral FitzRoy afforded, and still afford, ample means of checking them. " As regards the storm-warnings, detailed reports were called for from * Published by order of the Council. t Proceedings, vol. vii. p. 342. 1865.] on the Meteorological Department. 307 the places to which the warnings were sent. The results of these com- parisons for certain periods were tabulated and laid before Parliament in a paper, copy of which is annexed. The data for continuing the return are still kept, and, if it were thought right to incur the expense, it could be continued at any time. " My Lords at the same time addressed a further letter, dated 2/th February, 1863, asking the opinion of the Royal Society as to the course then being pursued by Admiral FitzRoy, and were favoured in reply by your letter of the 2/th March, 1863. "The vacancy in the Meteorological Department, occasioned by the death of Admiral FitzRoy, has seemed to My Lords to present a fitting opportunity toreview'the past proceedings and present state of the Depart- ment ; and with this view they are desirous of receiving any observations or suggestions, with which the President and Council of the Royal Society may be willing to favour them, on the constitution and objects of the Department, and the mode in which those objects may be most effectually attained. " The points on which the Board of Trade especially desire the opinion of the Royal Society are the following : — " 1. Are the objects specified in the Royal Society's letter of the 22nd February, 1855, still as important for the interests of Science and Naviga- tion as they were then considered ? " 2. To what extent have any of these objects been answered by what has already been done by the Meteorological Department ? " 3. "What steps should be taken for making use of any observations already collected, or any compilations already made by the Department? " 4. Is it desirable to make any, and what, further observations on any, and which of the subjects mentioned in the Royal Society's letter of 22nd February, 1855? ." 5. What is the nature of the basis on which the system of daily fore- casts and storm warnings established by Admiral FitzRoy rests ? In other words, are they founded on scientific principles, so that they, or either of them, can be carried on satisfactorily notwithstanding Admiral FitzRoy's decease ? " 6. If they, or either of them, can be carried on satisfactorily, can the Royal Society suggest any improvement in the form and manner of doing it ? " 7. Is it desirable to continue down to the present time the tables of results corresponding to the forecasts and storm warnings which were made out for certain periods in the year 1863, and were presented to Par- liament in April 1864 (Parliamentary Paper, No. 200, Session 1864, in- closed) ? The materials for doing this exist in the Office, and only require clerical labour. "8. Assuming it to be desirable to continue the publication of the daily reports of weather received from various stations, can the Royal Society 308 Correspondence with the Board of Trade [June, make any suggestions as to the extent to which it should be carried, and the form in which it should be done ? " 9. Have the Royal Society any general suggestions to make as to the mode, place, or establishment in, at, or by which the duties of the Meteo- rological Department can best be performed ? " With respect to these heads of inquiry, My Lords desire to observe, in the first place, that they understand that the Admiralty are willing to undertake, and to place in the hands of their Hydrographer, all those observations which can properly be made use of in framing charts for pur- poses of Navigation, but not those which relate to Meteorology proper. " Secondly. That the Board of Trade will gladly place the knowledge and services of Mr. Babington, Admiral Fitzroy's second, at the disposal of the Royal Society, for the purpose of the above inquiries, and will also give them any help, clerical or otherwise, which the Royal Society may require, and which the Board of Trade may be able to give. " I have the honour to be, "Sir, " Your obedient Servant, "T. H. FARRER." " The President of the Royal Society." Report by Mr. Babington on Forecasts and Storm-warnings, communicated with Mr. Farrer's Letter. " Meteorological Department, May 11, 1865. " The following is an attempt to comply with a request from Mr. Farrer for some explanation, in a few words, of the method adopted in this De- partment with regard to Forecasts and Storm Warnings — the basis on which forecasts have been made and cautions given. " Admiral FitzRoy has devoted three chapters (XIII., XIV., XV.) of his 'Weather Book' to this particular subject. I do not think the matter can be thoroughly comprehended without reference to those chapters. The very brief explanation which follows here must necessarily be most incomplete. "About ten o'clock each morning (except Sundays) telegrams are re- ceived here from about eighteen places round our own coasts, from a few French ports, and from Heligoland. These telegrams report (in cipher, for brevity) the state of the atmosphere, including pressure, temperature, wind direction and force, degree of dryness, rainfall, state of sky and sea, at each station. " The observations thus telegraphed are immediately reduced, or cor- rected, for scale-errors, elevation, and temperature, and are written into prepared forms. " The first copy, with all the telegrams, is passed to the chief of the department, or the person appointed by him, to be studied for that day's 1865.] on the Meteorological Department. 309 forecasts. At eleven, copies of the report, with forecasts, are sent out to 'The Times' (for second edition), to the 'Shipping Gazette,' and to the principal afternoon papers. Copies of the forecasts, only so far as they relate to weather expected in the Channel and on the French coasts, are telegraphed to Paris (by special request) for the Ministry of Marine. The whole of this work is finished by about half-past eleven, when every one in the department is free to turn his attention to other duties. Late in the afternoon telegrams are received from a very few selected stations. Should it appear necessary (which is now but seldom), in consequence of this later information, the morning's forecasts are more or less modified, and copies of the report are sent out for the next morning's early papers. " Besides this daily service, occasional storm warnings, or cautions, are sent to our own coasts and to Paris, and, when it appears advisable, also to Hamburg, Hanover, and Oldenburg, by the request and at the expense of the Governments of those States. "The basis upon which the forecasts and the cautions (which are merely forecasts symbolized) are founded, may be stated briefly as follows : — " They are the result of theory and experience combined. They are nqt predictions but opinions, although probably the best opinions that can be formed ; for it is manifest that if we know what is and has been occurring around an area several hundred miles in diameter, we are in a better position to form an opinion respecting the probable weather in a particular district than any person who has not such facts at command. " Considering, with Dove, that there are two constant principal wind- currents, north-east and south-west, of which the characteristics, especially with regard to temperature and degree of moisture or dryness, are totally distinct, all varieties of wind and weather in these latitudes may be traced to the operation of these two main currents — singly, in combination, or in antagonism — at times running in parallel lines but in opposite directions, frequently superposed, and occasionally meeting at various angles of incidence. "Upon the relative prevalence or failure of either or both of these currents all conditions of weather appear to depend. "It is clear that changes must begin at some places earlier than at others ; and the observations telegraphed daily to this department from the outports afford the means of forming a very good opinion respecting the nature and probable course of such changes. In a paper of this kind one or two examples must suffice, although the various examples that might be given are numerous, as also are the disturbing causes which must be taken into account by a Forecaster. " Suppose a northerly (E.N.E.-N.N.W.) current to have been pre- vailing generally over this country with fine weather ; the barometers at all the outports, during the continuance of such weather, will have been steady, or slowly rising, nearly uniform, or slightly higher at the northern than at the southern stations ; there will have been much evaporation, and 310 Correspondence with the Board of Trade [June, the sky will have been comparatively clear and free from cloud, while the temperatures, when free from the influence of radiation, will have been somewhat below the average. " Suppose now the northern barometers rise rapidly above the average, while the temperature remains low and the sky clear. This is an indication of more wind from a northern quarter, but probably without rain. Should, however, the southern barometers fall at the same time, while the tem- peratures in the south are much higher than in the north, the wind will probably increase to a gale from a northern quarter, and a sudden chilling of the atmosphere in the south will ensue, causing rain. "The first approach of a southerly current is usually indicated by a diminution of pressure (falling barometers) in the north and west, caused by a failure of the polar current ; the upper clouds are seen to be passing from the south, and the temperature increases. " Occasionally a temporary failure of both currents takes place. We may have very low barometers, but for a day or two little or no wind. Such a state of things, however, never continues long. It is then espe- cially necessary to watch for the first signs of approaching wind. The first indication is usually an increase of pressure in the direction from which the wind is coming. Should the French barometers rise rapidly or stand (say) an inch higher than in Scotland, the result will be a gale from the southward. Should both the French and the Scotch barometers rise rapidly, while in Ireland and central England the pressure continues very low, we may feel sure that both currents are approaching in force, and that the collision will be violent, causing much rain, and (according to the angle of incidence) either south-west and north-west gales, or a cyclonic movement, which experience has shown will probably advance in an easterly or north- easterly direction. On the other hand, should the increase of pressure be gradual and general, the combination of the two currents will be gradual also, and, though there may be rain, the winds will not be violent. " There are a few grand rules, which, though not always free from dis- turbing causes, may be considered as generally holding good. " 1st. The essentially distinct characteristics of the two main currents should never be forgotten. " 2nd. The direction of wind is usually from the place of high baro- meter towards the region of low barometer. "3rd. The force of wind is usually proportional to the differences of barometric pressure, not (as has been asserted by some) to the actual pressure. It matters little how low the barometer may be, if it is equally low for a considerable distance around. In such a case wind cannot follow at once, for there is no available supply at hand. " 4th. It was believed by Admiral FitzRoy that there exists a lateral transference of the whole body of atmosphere eastward. " Electrical and auroral occurrences should be carefully watched ; and the influence of high land, &c., must be borne in rnind. 1865.] on the Meteorological Department. 311 " There is another point in connexion with forecasting in which Admiral FitzRoy took great interest, namely, the frequency with which important atmospheric disturbances have been preceded by disturbances on electric wires above ground, and also on submarine wires. " No argument, or opinion, with regard to the advisability or otherwise of the continuance of the present system of forecasting is offered here, because none was asked for. I may mention, however, that the system, though at first objected to at the Paris Observatory, has since been adopted at that place, but that nevertheless the London forecasts are still sent daily to the French Ministry of Marine at the request of that department. " T. H. B." From General Sabine to Mr. Farrer. " Royal Society, Burlington House, " June 15, 1865. "Sin, — In replying to your Letter of the 26th of May, the President and Council think it may be desirable to advert in the first instance to that which has constituted the chief occupation of Admiral FitzRoy' s Depart- ment in the last four or five years, viz., the systematic forecasting of the weather by means of telegrams received from stations comprised within a certain limited area, and, on occasions of anticipated storms, the giving special warnings conveyed by telegraph to the different ports in the United Kingdom, and there made known by hoisting certain signals. " The system of forecasting which Admiral FitzRoy instituted and pur- sued has been expressly described by himself as ' an experimental process,' based on the knowledge conveyed by telegraph of the actual state of the winds and weather and other meteorological phenomena within a specified area, and on a comparison of these with the telegrams of the preceding days, so as to obtain inferences as to the probable changes in the succeeding days. The proper test of the efficiency and usefulness of such a system of cautionary signals at the different ports is to be sought in the measure of success which it appears to have attained — always remembering that the system under consideration can only be regarded as in its infancy, and that, if continued, its improvement, and consequently its importance, may be expected to be progressive from year to year. In Admiral FitzRoy's Report to the Board of Trade in May 1862, the opinions of the ship- masters at several ports in regard to the practical value which they attached to the storm-signals were given at length. Of the 56 replies published in the Appendix of that Report, 46 were decidedly favourable, 3 decidedly unfavourable, and 7 expressing no decided opinion. A statement so favour- able on the whole, obtained so very shortly after the system had been first brought into operation, must surely be considered to have fully justified the Board of Trade in directing its further prosecution. " The return to the House of Commons, dated April 13th, 1864, a copy of which accompanied your letter, presents a comparison of the probable force of the wind as indicated by the signals in the year commencing 312 Correspondence with the Board of Trade [June, April 1st, 1863, and terminating March 31st, 1864, and its actual state, as reported in the three days following the exhibition of the signals ; and Mr. Babington has since been so obliging as to communicate in manuscript a return having the same object in view for the year April 1st, 1864, to March 3 1st, 1865. "From the first of these documents, the President and Council learn (in p. 7) that the whole number of signals which were hoisted at different places, and of which reports were received, between April 1, 1863, and March 31, 1864, amounted to 2288; of these the number which proved correct in respect to the Force of the wind equalling or exceeding ' a fresh gale,' was 1 284 ; in 462 cases the stations were reached by the gale (or a still stronger wind blew) before the signal was hoisted ; and in 726 within forty-eight hours after the signal was hoisted. Hence we may conclude that (omitting the 96 cases in which the gale occurred between 48 and 72 hours after the signal was hoisted) 1188 signals, or more than half the whole number of 2288, were justified by the state of the weather, either when the telegraphic message reached the station, or within forty-eight hours afterwards. " With respect to direction of wind in a gale indicated by signal, the ' warnings' are reported to have been much less frequent. Of the 402 signals indicating direction as well as force, 271 agreed, and 131 did not agree with the real direction of the wind — being a proportion of about two correct to one incorrect. " The] manuscript with which Mr. Babington has favoured the Council since the receipt of your letter of May 26, 1865, contains a summary of the cautionary signals between April 1, 1864, and March 31, 1865, with notes stating their success or failure. From these it appears that signals were hoisted on 40 days in the course of the year, 29 of which appear to have been justified by the event, 8 to have been failures either in respect to force or direction, and 3 were late, the gale having already commenced. There are also 5 cases in which it is admitted that signals might have been made with advantage when none were sent. "It seems not unreasonable to attribute to increased experience the marked improvement of these results upon those of the preceding year, and to anticipate still further improvement. "The method adopted in preparing the storm-warnings has been very ably and lucidly explained by Mr. Babington in a paper dated May 11, 1865, presented by him to Mr. Farrer, by whom a copy has been sent to the President and Council. Possibly it may be viewed as the best arrange- ment that this branch of the duties of the office shonld continue as at present under the direction of Mr. Babington, by whom it has been virtually carried on for several months past. "On the subject of storms of a cyclonic character originating in the British Islands or in their vicinity, the interest of which was adverted to in the reply from the Royal Society to the Board of Trade, March 27, 1863, 1865.] on the Meteorological Department. 313 reference has been made to Mr. Babington for such further information as may have been subsequently obtained. His reply to General Sabine is as follows : — "'I can quite confirm your impression respecting Admiral FitzRoy's belief in the evidence of the existence of small cyclonic storms in England itself, originating in or near our islands, and generated in the brushing against each other of the N.E. and S.W. currents ; and in reply to your question I beg to say that I believe there is satisfactory evidence of the existence of such storms, but that these small storms are not very frequent — three or four in a year perhaps — and that they are, I think, more common in summer than in winter, although usually of less violence. The direction of their motion is certainly almost invariably towards some point between N.N.E. and E.S.E. With regard to the rapidity of their motion, I scarcely feel able to express an opinion ; but at the ordinary rate of progression it takes such a storm about forty -eight hours to pass from Ireland to the Baltic. Not unfrequently, however, they appear to die out (as it were) before travelling so far.' " The existence of such storms in our islands is a fact in meteorological science of considerable interest, for which we are indebted to the researches instituted and carried on by Admiral FitzRoy's department.- Though not of very frequent occurrence, they constitute a class of phenomena well suited for telegraphic advertisement, especially on our eastern and north- eastern coasts. It might perhaps be practically desirable to indicate them by a special signal, distinguishing them from storms which have a more uniform direction. But however this may be, it seems to be desirable that the occurrence of such storms and their attendant phenomena, as obtainable at the time, shojild be carefully recorded, with a view to the records being ultimately put together in elucidation of a branch of the meteorology of our islands which has hitherto been but imperfectly examined. " We proceed to notice the points on which we are informed that the Board of Trade especially desire the opinion of the Royal Society — and particularly the inquiry whether the objects specified in the Royal Society's letter of the 22nd of February 1855 are still viewed as of the same importance for the interests of science and navigation as they were then considered. " The most prominent amongst these objects was the collection and co- ordination of meteorological observations made at sea, including such as are required to form a correct knowledge of the currents of the ocean, their direction, extent, velocity, and the temperature of the surface water rela- tively to the ordinary ocean temperature in the same latitude, together with the variations in all these respects which currents experience in dif- ferent parts of the year and in different parts of their course. These — as well as the facts connected with the great barometric elevations and depres- sions which we know to exist in several oceanic localities, and their influence on circumstances affecting navigation — were noticed as inquiries well de- 314 Correspondence with the Board of Trade [Juno, serving the attention of a country possessing such extensive maritime faci- lities and interests as ours, and as forming a suitable contribution on our part to the general system of meteorological inquiry which had been adopted by the principal continental states in Europe and America. " We have learnt from Mr. Babington that much was done by Admiral FitzRoy in the three or four years succeeding the establishment of his office (and before the subject of storm-warnings had engrossed the greater part of his consideration), in directing the attention of many of the com- manders of our merchant ships to the collection of suitable data, and in improving their habits of observation and of record. The logs of such vessels form at present a large collection of documents existing in the Office of the Board of Trade, partially examined, and their contents partially classified. The President and Council are glad to learn by your letter that the further prosecution of this great and important branch of Hydrography is about to be placed in the hands of the distinguished officer who now presides over the Hydrographic Department of the Admiralty ; to whose duties it appears indeed most appropriately to belong, and to whose office no doubt the documents already collected will be transferred and made available for public purposes. " There remain, therefore, to be noticed solely the considerations which relate to 'Meteorology proper,' i. e. to the Land Meteorology of the British Islands. We find that the principal States of the European con- tinent have almost without exception formed establishments for the collec- tion and publication periodically of the meteorology of their respective countries. The arrangements consist usually of a central office, at which instruments and instructions are provided for a number of stations, greater or less, according to the area which they represent ; at which stations ob- servations are made and transmitted to the central office, where the results of all are reduced, coordinated, and published. The small extent of the area comprised by the British Islands in comparison with the territories of many of the European States, may require fewer stations ; but in a matter now so generally attended to and provided for, it seems scarcely fitting that our country should be behind others. There is, moreover, a peculia- rity in the meteorological position of the British Islands in respect to Europe generally as its north-western outpost, in consequence of which an especial duty appears to devolve upon us. M. Matteucci, in a very recent publication, has already made the important remark that extensive atmo- spheric disturbances which first invade Ireland and England are those which, in winter more especial!}-, extend to and pass the Alps (although somewhat retarded by them), and spread over Italy — and thus that, though receiving telegrams announcing storms taking place in the North of Europe, in Germany, on the western coasts of France, and of those of Spain, he finds that it has in fact been most especially in the case of announcements from England that storms so telegraphed have actually 1865.] on the Meteorological Department. 315 reached Italy, and been found to correspond with the accounts subse- quently received from Italian Mediterranean ports. "A few stations, — say six, distributed at nearly equal distances in a meridional direction from the south of England to the north of Scotland, furnished with self-recording instruments supplied from and duly verified at one of the stations regarded as a central station, and exhibiting a con- tinuous record of the temperature, pressure, electric, and hygrometric state of the atmosphere, and of the force and direction of the wind — might perhaps be sufficient to supply authoritative knowledge of those peculia- rities in the meteorology of our country which would be viewed as of the most importance to other countries, and would at the same time form authentic points of reference for the use of our own meteorologists. The scientific progress of meteorology from this time forward requires indeed such continuous records, first, for the sake of the knowledge which they alone can effectively supply, and next, for comparison with the results of independent observation not continuous. The actual photograms, or other mechanical representations, transmitted weekly by post to the central station would constitute a lithographed page for each day in the year, com- prehending the phenomena at all the six stations, each separate curve admitting of exact measurement from its own base-line, the precise value of which might in every case be specified. " The President and Council suggest that the Observatory of the British Association at Kew might, with much propriety and public advantage, be adopted as the central meteorological station. It already possesses the principal self-recording instruments, and the greater part of them have been in constant use there for many months. There will be no difficulty in obtaining, through the intervention of the Committee of Management, similar instruments for the affiliated meteorological stations, and in arrang- ing for their verification and comparison with the Kew standards, as well as in giving to those in whose hands they may be placed such instructions as may ensure uniformity of operation. The records from the other stations may be received at Kew by post weekly, or more frequently if required, and may be at once arranged for such form of publication as may be%most approved. It seems expedient that, if practicable, the stations which should be selected to act in concert and cooperation with Kew should be in localities where some permanent establishment of a scientific character exists, and where a certain amount of supervision may be secured. In this view the President and Council would suggest, as eligible, the follow- ing chain of stations, commencing from the south, viz. :— o * Falmouth — Polytechnic Institution Lat. 50 9 Kew — Observatory of the British Association .... „ 51 28 Stonyhurst — The College, which has already a mag- netical and meteorological observatory „ 53 0 Armagh — Observatory „ 54 21 VOL. xiv. 2 A 31 6 Correspondence with the Board of Trade [June O / Glasgow — University and Observatory Lat. 55 51 Aberdeen — University „ 57 9 "To these six stations the President and Council would have been very glud to have added two others, one in the south-west and one in the north- west of Ireland. For the former of these, possibly Yalentia may present a fitting locality, when an establishment shall have been formed there as the connecting link, by means of the Atlantic Telegraph between Europe and America. " Having answered thus generally, it may perhaps be desirable to add specific replies on the several points enumerated in Questions 1 to 9. Preserving the order in which the inquiries are made, the replies are as follows : — " Question 1. The President and Council are of opinion that the objects specified in the Royal Society's letter of February 22, 1855, are as important for the interests of science and navigation as they were then considered. " Question 2. — Much has without doubt been accomplished in the col- lection of facts bearing on Marine Meteorology, but as no syste- matic publication of the results has yet been made, the President and Council are unable to reply more specifically. " Question 3. — The President and Council recommend that the Sea Observations should be placed in the hands of the Hydrographer, with a view to the introduction of the results into the Admiralty Charts. They, however, at present have not sufficient information on the subject of the Land Observations which may exist in the office of the Board of Trade to justify them in offering any recom- mendation thereon. "Question 4. — The President and Council consider it very desirable that further observations should be made, especially with reference to oceanic currents and great barometric depressions, and generally on all subjects comprehended under the denomination of ' Ocean 0 Statistics.' " Questions 5 & 6. — It appears from the late Admiral FitzRoy's reports, as well as from the explanations of Mr. Babington, that the storm- warnings have been based on inferences drawn from observations extending over a considerable area ; and the President and Council recommend that they should be continued under the superin- tendence of that gentleman. Respecting the daily forecasts of weather, however, they decline expressing any opinion. " Question 7. — The President and Council are of opinion that it would be desirable that an annual report in a modified form should be made to the Board of Trade of the results from the storm-warnings in the preceding year, and should be communicated to Parliament, and thereby become known to the public. 1865.] on the Meteorological Department. 317 " Question 8. — A proper reply to this question would require informa- tion and involve considerations which would occasion an incon- venient delay in the transmission of this letter. " Question 9. — The suggestions of the President and Council in regard to the mode in which it appears to them that the important subject of ' Meteorology Proper,' or the ' Land Meteorology of the British Islands,' might be dealt with economically, and at the same time effectively, have been fully stated in the body of this letter. " I have the honour to be, Sir, " Your obedient Servant, " EDWARD SABINE, " President of the Royal Society" Extracts from a Letter to the President from Professor Dove, of Berlin, dated June \2th, 1865. " Berlin. " My views respecting the way in which meteorological communications may be made available for practical use in storm-warnings are in general accordance with the methods followed in England ; yet I acknowledge that I do not trust myself to announce daily probabilities, at least with the but limited communications which reach me telegraphically. My investi- gations in regard to storms have hitherto had relation to great atmospheric disturbances in autumn and winter, hardly at all to the storms of summer, in which the derangements of atmospheric equilibrium are much more local, and therefore the limits of the region overspread by the storm much narrower. This is particularly true of the storms of the Baltic. There, relative barometric minima occur, which seem to be cut off as it were towards the south. Probably the upper equatorial current first comes down in those high latitudes, breaking into the locally warm moist air, and occa- sioning a north-west wind at the south end of the Scandinavian mountain ranges, over the Kattegat and the lowlands of Denmark. Yet it is pro- bable that these disturbances are less local than they may seem to the in- habitants of Western Europe, for they extend into the interior of Russia, and may become more intelligible when viewed in combination with tele- graphically communicated data from Russia. All this must be studied if too hasty conclusions are to be avoided. " We have introduced the English warning- signals into our Baltic ports. We leave to authorities at the ports who are conversant with the subject a discretionary power of showing warnings, in so far as they may be able to form a judgment from the telegrams which we send them of our observations here, and the general appearance of the sky, &c., viewed in connexion with the whole local character of the weather ; but it is imperative on them to hoist a signal when an actual storm-warning is telegraphed from Berlin. I wished to introduce the system gradually. I consulted with Kupffer, who had similar views. His death is a new misfortune, following so shortly the loss of Admiral FitzRoy, to whom I owed great thanks for 2 A2 318 Letter of Professor Dove [June much kindness. Also I had concerted with Kupffer and Plantamour for attending the Swiss Scientific Meeting at Geneva at the end of August, and inviting the heads of the different systems of observation to assemble there, and consult in common as to the best modes of treatment, commu- nication, and publication. This must, no doubt, now stand over. As to the data to be communicated, it is no doubt right to give, as now, the height of the barometer at the moment the telegram is despatched ; but I think it would be desirable to add a sign indicating whether the barometer is rising or falling. The cotemporaneous temperature is in many cases desirable, and thus I think that this communication might be so arranged that some scientific result could be based thereon. If the maximum and minimum of the preceding day had heretofore been telegraphed, we should have gained six or seven years' materials for enabling us to judge whether the day of the telegram was a relatively warm or cold one. The same hour has in the diurnal variation a very different meaning in different parts of the year ; and in the summer months it is difficult to draw any definite conclu- sions from the temperatures at seven or eight o'clock. It seems to me, moreover, that in the present modes too little consideration is given to first laying down what it is desired to obtain. For England, for instance, the reduction of the barometer to the level of the sea is not difficult ; but yet there are many land-stations in which one does not know whether this reduction has been made or not. Advances in meteorology are based on long-continued labours : we seem now to want to take it by storm ; this may dazzle the public, but the results need control if they are to be recog- nized as really such. " The idea that all storms are cyclones is indeed given up by most, and I have lately been taking some pains to contribute thereto. The introduc- tion of the word ' cyclonoid ' means nothing more than that for a given case it is wished to leave the matter undecided. It is a retrograde step. " I have read with great interest the paper headed ' Forecasts and Cautions ' kindly sent to me. It seems to me very suitable to the desired end. I cannot recognize any connexion with electrical currents ; I cannot discern any proper bases for doing so. " For meteorology itself, I should deem it extremely advantageous if, as you contemplate, the immediate data of observation in England were placed under a common guidance such as that of the Kew Observatory. The British Association does indeed represent in the freest and most inde- pendent manner scientific Great Britain as a whole. I do not certainly recognize what the British and Scottish Meteorological Societies have supplied in this direction ; but an accordant mode of publication and treatment would still give quite other results. So, for example, in the monthly communications the notice of the barometric extremes of the month with the indispensable mention of the date of their occurrence is wanting. These are the very things by means of which it is possible to examine profitably the particular phenomena of a storm. 1865.] on Meteorological Communications, fyc. 319 " The small pecuniary resources of our Meteorological Institute, which now includes ninety-seven stations, do not permit me to publish the daily means. I have therefore had to content myself with five-day means ; but I think that by the consequent calculation of deviations I have brought some questions nearer to a solution. But I have to do this work by myself, and, overcharged as I am besides with official duties, I do not think I shall long be able to continue to master it. The resources which the British Association offers to all scientific undertakings in England will make it possible for you to establish in a thorough manner the constants of a climatology of England, and to investigate on this climatological basis the meteorology of England. " I had long proposed to myself to write from my own point of view a pamphlet ' how to observe ' in meteorology ; but when one has, as I have constantly, to give lectures in the day, and hold examinations in the even- ing till nine o'clock, much that has been contemplated is left undone In regard to telegraphic communications, Admiral FitzRoy once said to me that reports from Eastern Europe were of little interest for England. This may be granted where it is question of the storms which assail the English and Irish coasts themselves. But the commerce of the Baltic is for the greater part in the hands of Englishmen, and I think that it would there- fore be conducive to English interests also if the efforts were facilitated which are made by others to lessen the dangers to shipping in the Baltic. As it is precisely north-west storms which are the most dangerous in that sea, communications from England are wanted for this. Among the numerous telegraphic communications received here daily, there are none from England. Would it not be possible to arrange an exchange, if only for one or two stations ? The communication might be made through Tb'nningen, by the cable, so as to avoid the German-Austrian Telegraph Company, which declines to afford a gratuitous passage for our messages. " Harbour signal arrangements are now established at Memel, Pillau, Neufahrwasser, Stolpemiinde, Riigenwalde, Colbergermiinde, Swinemtinde, Greifswald, Stralsund, and Earth." June 15, 1865. Major-General SABINE, President, in the Chair. The Rev. W. R. Dawes, Mr. George Gore, Dr. George Harley, Mr. W. Huggins, Mr. Fleeming Jenkin, and Mr. \V. K. Parker, were admitted into the Society. The following communications were read : — 320 Mr. Gassiot — Description of a Rigid Spectroscope. [June 15, I. " Description of a Rigid Spectroscope, constructed to ascertain whether the Position of the known and well-defined Lines of a Spectrum is constant while the Coefficient of Terrestrial Gravity under which the Observations are taken is made to vary/' By J. P. GASSIOT, V.P.R.S. Received May 18, 1865. Shortly after my large spectroscope * had been removed to Kew Ob- servatory, Mr. Stewart mentioned to me that he had had some con- versation with Professor Tait of Edinburgh, as to the practicability of having a spectroscope constructed so as to preclude all errors of observa- tions arising from a displacement of the prisms or the shifting of any of the fixed portions of the apparatus. The particular object Mr. Tait and Mr. Stewart had in view, was the de- termining whether the positions of the known and well-defined lines of the spectrum are constant While the coefficient of terrestrial gravity, under which the observations are taken, is made to vary, Mr. Stewart consider- ing that, provided an instrument could be constructed so rigid in all its parts as to preclude all possibility of error, the observations might be made in balloon ascents, varying from two to four miles. I consulted with Mr. Browning as to the practicability of constructing the spectroscope. He considered such an instrument could be made, with sufficient rigidity in all its parts, to examine with great accuracy any given portion of the spectrum which might be selected, and for which the prisms would have to be adjusted and fixed. I communicated with Mr. Coxwell relative to the balloon ascents which would be required, and then deter- mined on having the spectroscope constructed. On testing the alteration in the position of the lines arising from change of temperature, it was soon ascertained that the difficulty of constructing a truly rigid spectroscope was far greater than had been anticipated. By the description of the apparatus, it will be seen that the prisms are arranged so as to bring the D-lines into the centre of the field of view (fig. in margin), with a few of the fainter lines on each side; a perpendicular fixed line, and two cross moveable lines in the cobweb micrometer eye- n-iines as seen with «. T i „ ^ the Rigid Spectro- piece, affording the means of measuring to IQ *QO of an scope. inch, whatever alteration takes place in the position of the lines. The observations having been originally intended to be made in balloon ascents, the construction of the spectroscope had necessarily to be con- sidered in reference to some portable and easily manageable form, and it was particularly desirable that its weight should be as low as possible. These conditions were obtained by constructing and mounting it in a T-shaped frame of gun-metal : in this manner the instrument was com- pleted so as to weigh little more than 40 Ibs. ; but on carefully examining the readings day by day in Mr. Browning's workshop, the errors arising * Proceedings of Koyal Society, vol. xii. p. 536. 1865.] Mr. Gassiot — Description of a Rigid Spectroscope. 321 from changes in the temperature were ascertained to be so variable that no reliable result could have been obtained. These preliminary observations were nevertheless so far valuable, for they proved that changes of temperature were taken up very slowly by the prisms, and that it would be consequently useless to employ the instrument in balloon ascents where rapid fluctuations of temperature would continu- ally occur. I then determined to attempt the construction of a rigid spectroscope with which observations might be made either on board a vessel or on land, in various latitudes ; and as the question of the total weight of the apparatus became no longer of paramount importance, Mr. Browning de- cided on mounting the instrument in cast iron. The adjustments of the telescope being dispensed with, it was mounted in two cast-iron blocks, and fixed on a bed of slate; the prisms, with their adjustments, were attached to an iron plate, the plate being bolted to the same slate-bed. In this arrangement the observations still showed discrepancies, which were con- sidered to arise from changes in the adjustments of the prisms, produced by alterations of temperature. Mr. Browning then removed all the ad- justments of the prisms, and also the iron bed-plate, bolting the prisms on the bed of slate, and securing their correct position by filing and scraping. Full particulars of this arrangement will be found in the description of the apparatus. The instrument has been carefully examined by Mr. Stewart, not only at Kew Observatory but also from time to time during the progress of its construction, as well as after it was completed in Mr. Browning's work- shops ; and it may now be considered that, with ordinary care during its transit from place to place, any observations made with it can be depended on as far as the mechanical arrangement is concerned. I am indebted to Mr. Browning for the description of the apparatus, with the notes of the readings as they were made by himself. The optical arrangement is as follows : — In order to obtain great re- fractive power in a moderate compass, the prisms were arranged as in Plate VI. fig. 1. P and P' represent two prisms of heavy flint glass, having sides 2| inches high, and 3 inches long. These prisms have refracting angles of 45°. They are arranged at the minimum angle of deviation for Fraunhofer's line D. E. represents a prism of similar material and dimen- sions, but with a refracting angle of 22° 30', that is half P and P'. The dense flint glass of which these prisms are composed was made by Messrs. Chance Brothers and Co. It has a specific gravity of 3 '9. Its mean refractive index is 1*665, and its dispersive power 0-0752. The prism R has the side further from P and P' silvered. The nearest side is placed at the same minimum angle of deviation from P as P is from P'. D andD' represent a compound prism, formed by cementing a very small diagonal prism D' on to a large diagonal prism D with a transparent cement, in such a manner that two of the plane surfaces are parallel. They 322 Mr. Gassiot — Description of a Rigid Spectroscope. [June 15, are both made of hard white optic crown glass, cut from the same hlock. O is an achromatic ohject-glass of 2!3 inches aperture, and 3 feet focal length. M is a cobweb micrometer eyepiece, having one fixed vertical web, and two which are crossed, moving together ; also a fine rack in the field of view, which serves to register whole turns of the micrometer head (fig. 4). S is a pair of knife-edges. The action is as follows : when any source of light is brought in front of the knife-edges S, some of the rays emitted pass through them, and unchanged through the double diagonal prism D, D', as shown on a large scale in diagram 2. As the object-glass O is placed at its focal distance from the knife-edges, the rays in passing through it are rendered parallel ; on entering and emerging from P', P these rays suffer refraction, and also, if the light be not homogeneous, dispersion. The same effects are produced as the rays enter the first surface of E, and again emerge from it, after being reflected from the further side, which, as has been previously mentioned, is silvered. They now retrace their way through the prisms P and P', the refraction and dis- persion being doubled in this return passage. In this manner a result is obtained equal to that which would be produced by five prisms, if em- ployed in the ordinary manner. Repassing through O, this compound lens, which before acted as a collimator, now acts as the object-glass of the telescope T. The cone of rays produced by this lens falls on the prism D D', figs. 1 & 2, and is reflected from the diagonal side, a loss of light determined by the size of the small prism D being experienced ; but as this prism need be but little more than the length and width of the slit formed by the knife-edges, the loss may, practically, be considered unimportant. In figs. 1 & 2 the continuous line represents the rays of light in their first passage through the prisms, and the dotted lines the same rays re- turning through the instrument. The image of the slit is viewed, and any change in its position observed, by means of the micrometer eyepiece M. Owing to the power of the instrument, only a very small portion of the spectrum can be seen at once in the field of view. The reflecting prism R is, however, provided with a tangent screw motion, which affords the means of bringing any portion of the spectrum into the field of view that it may be desired to examine. Although having to contend with several disadvantages on the score of reflexions not made use of in spectroscopes of the ordinary construction, and which of course cause loss of light and tend to deteriorate the defi- nition, yet it will, I think, be admitted that the performance of the in- strument is satisfactory. Mr. W. Huggins has seen two bright lines between the D-lines pro- duced by the flame of a common spirit lamp ; and several persons have seen on different occasions from five to seven lines between the D-lines in the solar spectrum. This is equal to the performance of my large spectro- scope, with which the solar spectrum is now being mapped at Kew Ob- Proc Ray. Soo. VolJZV. Plate VI. Rgl. 0 T A Eg 4. J-.BasM. 1865.] Mr. Gassiot — Description of a Rigid Spectroscope. 323 servatory, although that instrument has nine prisms. The prisms of that spectroscope are, however, hut little more than half the size of those in the rigid instrument now described. It is to the large size of the prisms, and the greater aperture and focal length of the object-glass, that the superior performance of this instrument must be attributed. The temperature of the air and of the prisms is thus observed : — A third prism (T P, fig. 3), exactly similar to P and P', is mounted on the slate block. This prism has a hole about | an inch diameter and 1| inch deep drilled in it vertically. A thermometer (Plate VI. T, fig. 3) with a fine cylindrical bulb is inserted in this hole, the intervening space being packed tight with copper filings. The upper part is covered with a layer of fused shell-lac. That the half prism may be about the same temperature as the whole prisms, another half is cemented to it. To avoid confusion, this half is not represented in the diagrams. The thermometer, after leaving the prism, is bent at right angles, and is carried across the top of the prisms on a light metal frame. Another thermometer (T', fig. 3), whose bulb is in the air, its object being to denote the temperature of the air around the prisms, runs parallel with that just described. Both the prisms and thermometers are enclosed under a metal cover, for the purpose of equalizing the tempe- rature and protecting them from injury. This cover has a long slip of stout plate-glass let into the upper part of it, through which the thermo- meters can be seen, and their readings observed. The micrometer eye- piece and the cell containing the object-glass are each mounted on distinct iron blocks. The body of the telescope which fills up the intervening space is mounted on two separate iron blocks not connected with those just mentioned. The tube which forms the body overlaps at one end the tube of the eyepiece, and at the other the mounting of the object-glass, but without being in contact with either. By this means the change of length in the body-tube, produced by change of temperature, by far the most con- siderable change we have to contend with, is prevented from exerting any influence on the indications given by the instrument. The homogeneous light of the sodium-flame is employed, and the mi- crometer wires are lighted up by the contrivance shown in fig. 4. A portion of the cap on which the knife-edges are fitted is cut away, and the light which is thus admitted enables the wires, and the rack that serves to register whole turns of the micrometer screw, to be seen distinctly *. A whole turn of the micrometer screw values — J-p- of an inch, so that the first reading in Table I. might have been written 0'0552. In making remarks on differences in the readings, they will be expressed in this manner, the reading of the line D decreasing with the rise in the temperature of the prisms. The object in taking the readings of the D-line, which are appended, was * In fig. 4 the bright lines of sodium, as seen in the rigid spectroscope, are repre- sented ; the spaces A, A are cut away, allowing the light from the sodium-flame to enter and illuminate the field enough to render the cobwebs visible. 324 Mr. Gassiot — Description of a Riff id Spectroscope. [June 15, to endeavour to determine the temperature corrections which it will be necessary to apply to the results obtained by the instrument, and also to find if the line resumed its position exactly after the instrument had been subjected to considerable changes of temperature, or carried from place to place. From Tables III. and IV. it may be noted that the readings have a constant downward tendency. To endeavour to account for this retro- gression, I can only venture to hazard the suggestion that the index of refraction of the glass of which the prisms are made may be slightly varying from some change due to annealing not having yet been entirely completed. Although showing generally a downward tendency, the decline is not quite uniform, and there are some apparent discrepancies in the readings ; these may be errors of observation, arising principally from differences of intensity in the source of illumination. Such differences tend to alter the width of the bright line observed ; and as one of its edges is taken for the point of measurement, the position of the line is apparently changed. Mr. Stewart is, however, of opinion that these variations are so slight that they will not be likely to interfere with the instrument being used for the purpose for which it was designed. TABLE I. Readings of one of the D-lines taken with the Rigid Spectroscope at the Minories. Temp. Temp. Difference in Date. Air. Prism. Micrometer. divisions. February 1 5°7'5 52'5 5-521 Ioo.n oo.r /?.*Ti-» i *• ***-' • 2. .3. 6. 6. RQ.A CQ.A K.AC ~\ 1-18 Q O^.A o r» . r /? . i A f 11 57-5 52-5 4-85 Results from 6th to 1 Hh : — Variation in temperature correction for a change of temperature of 30° O-OOO/ inch. Separation of D-lines 0'004 inch. 57-5 88-0 52-5 82-5 5-521 6-72J 90-0 52-0 82-5 52-5 6-551 5-28 J 56-0 90-5 52-5 82-5 4-981 6-15 1 53-0 95-5 53-0 82-5 5-05 1 6-23 J 54-0 84-0 82-5 6-10 J 1865.] Mr. Gassiot — Description of a Rigid Spectroscope. 325 TABLE II. Temp. Temp. Difference Date. Air. Prism. Eeadings. for 20°. February 16 4°8'5 42 -5 4-60] „ .... 58-0 52-5 5-09 I = 0-96 „ 69-5 62-5 5-56 J 17 50-0 42-5 4- ] „ 57-5 52-5 5-08 I = 0'92 „ 67-5 62-5 5-54 j 18 48-0 42-5 4-60 Variation of temperature correction for a change of temperature of 20° 0-0004 inch. TABLE III. Temp. Temp. Date. Air. Prism Eeadings. February 20. .. .. 56-0 52-5 4-98 » 21. .. .. 56-0 » » 4-88 is 22. .. .. 58-0 » >} 4-90 » 23. .. .. 53-0 » » 4-89 j> 24. .. .. 53-5 » » 4-92 „ 27. .. .. 53-0 a » 4-88 ,, 28. .. .. 52-5 it 53 4-94 March 1. .. .. 56-0 » >» 4-96 » 2. .. . . 56-5 4-93 }) 7. .. .. 56.0 „ „ 4-84 „ 8. .. .. 56-0 JJ » 4-84 „ 9. .. .. 58-0 „ „ 4-82 Decrease of zero, 0-0016 of an inch. Having thus far satisfied ourselves by observing under varied tempera- tures, and also that the removal of the instrument to different parts of Mr. Browning's premises did not affect the readings on the 22nd of March, the apparatus was removed in a cart to Kew Observatory, and placed in one of the rooms for observing, when the following readings were made : — Temp. Temp. Date. Air. Prisms. Beading. March 23 4°5'0 4°2'2 4'57 Mean of readings taken in the Minories, at a temperature of 420>5, 4'60 ; change of zero during the transit, 0'0003 of an inch. Observations were subsequently continued under the direction of Mr. Stewart. 326 Mr. Gassiot — Description of a Rigid Spectroscope. [June 15, TABLE IV. Readings taken by Mr. Beckley at Kew Observatory. Temp. Temp. Micrometer Date. Air. Prism. reading. April 3 57'5 5°6'8 573 ,,28 57-2 56-8 5-53 „ 3 55-1 54-3 5-66 „ 6 56-0 54-5 5-41 9 55-0 58-4 5-44 May 3 53*6 58'4 5'47 Decrease of zero in the month, -0026. On the 5th of May the spectroscope was removed to the rooms of the Royal Society, Burlington House, where it still remains. The result of observing under a varied temperature of 40° Fahr., the carrying of the instrument from the Minories to Kew Observatory, and subsequently to the Royal Society, without affecting the readings, may be taken as evidence that with ordinary care the spectroscope can now be used with reliance as to the rigidity of its construction, thus fulfilling the conditions which are indispensable for obtaining correct observations. It will be observed that it was my intention to have made arrange- ments with Mr. Coxwell for the observations being made with his bal- loon, but the weight of the entire apparatus (approaching two hundred weight), and still more the difficulty of obtaining a uniform temperature throughout the prisms, renders observing in this manner very difficult, if not impracticable ; I therefore suggested to Mr. Stewart that, if the ob- servations were made in different latitudes, the object sought would be obtained in a more satisfactory manner. The best, and probably the most satisfactory mode of observing, would be to obtain the sanction of the Admiralty to allow the spectroscope to be placed on board one of Her Majesty's vessels about visiting various lati- tudes ; continued observations could then be made, and the result thereof from time to time forwarded to Kew Observatory. Mr. Stewart writes me, that to this time it has been assumed, without proof, that the change of the coefficient of terrestrial gravity does not in itself alter any other coefficient of a body ; and if a reason is asked, none can be given, since gravity is a force of the nature of which men of science are confessedly ignorant, and that it would therefore be very desir- able that experiments should be undertaken with the view of setting this matter at rest. It is to determine this, as far as the index of refraction is concerned, that the spectroscope I have described has been constructed, and the assistance of the President and Council of the Royal Society will be asked, in order that the observations may be made with this apparatus by some trustworthy observer, on board any of Her Majesty's ships, from one point to another of the earth's surface. 1865.] On Fossil Plants from the Coal of Lancashire, $c. 327 II. "A Description of some Fossil Plants, showing structure, found in the Lower Coal-seams of Lancashire and Yorkshire." By E. W. BINNEY, F.R.S. Received May 12, 1865. (Abstract.) The author stated that, although great attention has been devoted to the collection of the fossil remains of plants with which our coal-fields abound, the specimens are generally in very fragmentary and distorted conditions as they occur imbedded in the rocks in which they are entombed ; but when they have been removed, cut into shape, and trimmed, and are seen in cabinets, they are in a far worse condition. This is as to their external forms and characters. When we come to examine their internal structure, and ascertain their true nature, we find still greater difficulties, from the rarity of specimens displaying both the external form and the internal structure of the original plant. It is often very difficult to decide which is the outside, different parts of the stem dividing and exposing varied surfaces which have been described as distinct genera of plants. The specimens described were collected by the author himself, and taken out of the seams of coal, just as they occurred in the matrix in which they were found imbedded, by his own hands. This has enabled him to speak with certainty as to the condition and locality in which they were met with. By the ingenuity of the late Mr. Nicol of Edinburgh, we were furnished with a beautiful method of slicing specimens of fossil-wood so as to examine their internal structure. The late Mr. Witham, assisted by Mr. Nicol, first applied this successfully, and his work on the internal structure of fossil vegetables was published in 1833. In describing his specimens, he notices one which he designated Anabathra pulcherrima. This did not do much more than afford evidence of the internal vascular cylinder arranged in radiating series, somewhat similar to that described by Messrs. Lindley and Hutton as occurring in Stiymaria faoides, in the third volume of the « Fossil Flora.' In 1839 M. Adolphe Brongniart published his truly valuable memoir, " Observations sur la structure interieure du Siyillaria elegans comparee a celle des Lepidodendron et des Stigmaria et a celle des vegetaux vivants," in the Archives du Muse'um d'Histoire Naturelle. His specimen of Sigillaria elegans was in very perfect preservation, and showed its external characters and internal structure in every portion except the pith and a broad part of the plant intervening betwixt the internal and external radiating cylinders. Up to this time nothing had been seen at all to be compared to M. Brongniart' s specimen, and no person could have been better selected to describe and illustrate it. His memoir will always be considered as one of the most valuable ever contributed on the fossil flora of the Carboniferous period. 328 On Fossil Plants from the Coal of Lancashire, fyc. [June 15, In 1849, August Joseph Corda published his 'Beitrage zur Flora der Vorwelt,' a work of great labour and research. Amongst his numerous specimens, he describes and illustrates one of Diploxylon cycadeoideum, which, although not to be compared to M. Brongniart's specimen, still affords us valuable information, confirming some of that author's views rather than affording much more original information. All these last three specimens M. Brongniart, in his ' Tableau de vegetaux fossiles con- side'rees sous le point de vue de leur classification botanique et de leur dis- tribution geologique,' published in 1847, classes as Dicotyledones gymno- spermes under the family of Sigillarees ; amongst other plants his Sigil- laria elegans, Mr. Witham's Anabathra, and Corda's Diploxylon. In 1862 the author published, in the 'Quarterly Journal of the Geolo- gical Society ' of that year, an account of specimens which confirmed the views of the three learned authors above named as to Sigillaria and Diploxylon being allied plants ; but showed that their supposed pith or central axis was not composed of cellular tissue, but of different sized vessels arranged without order, having their sides barred by transverse striae like the internal vascular cylinders of Sigillaria and Lepidodendron. These specimens were in very perfect preservation, and showed the ex- ternal as well as the internal characters of the plants. All the above specimens were of comparatively small size, with the exception of that described by Mr. Corda, which, although it showed the external characters in a decorticated state, did not exhibit any outward resemblance to a plant allied to Sigillaria with large ribs and deep furrows so commonly met with in our coal-fields, but rather to plants allied to Sigil- laria elegans and Lepidodendron. In the present communication the author has described some specimens of larger size than those previously alluded to, and endeavoured to show that the Sigillaria vascularis with rhomboidal scars gradually passes as it grows older into ribbed and furrowed Sigillaria, and that this singular plant not only possesses two woody cylinders arranged in radiating series, an in- ternal and an external one divided by a zone of cellular tissue, both increas- ing on their outsides at the same time, but likewise has a central axis composed of hexagonal vessels, arranged without order, having all their sides marked with transverse striae. Evidence is also adduced to show that Sigillaria dichotomizes in its branches something like Lepidodendron, and that, like the latter plant, a Lepidostrobus is its fructification. The outer cylinder in large Sigillaria is composed of thick-walled quadran- gular tubes or utricles arranged in radiating series, and exhibiting every appearance of having been as hard-wooded a tree as Pinites, but as yet no disks or striae have been observed on the walls of the tubes. Stigmaria is now so generally considered to be the root of Sigillaria, that it is scarcely necessary to bring any further proof of this proposition ; but specimens are described which prove by similarity of structure that the former is the root of the latter. 1865.] Mr. W. H. L. Russell on Symbolical Expansions. 329 The chief specimens described in the memoir are eight in number, and were found in the lower divisions of the Lancashire and Yorkshire coal- measures imbedded in calcareous nodules occurring in seams of coal. No. 1, Diploxylon cycadoldeum, was from the first-named district, and the same locality as the Trigonocarpon, described by Dr. J. D. Hooker, F.R.S., and the author, in a memoir on the structure of certain limestone nodules inclosed in seams of bituminous coal, with a description of some Trigonocarpons contained therein*, and the other seven (Sigillaria vascu- laris) were from the same seam of coal in the lower coal-measures in which the specimens described in a paper entitled " On some Fossil Plants showing structure from the Lower Coal-measures of Lancashire " f, were met with, but from a different locality in Yorkshire. III. " On Symbolical Expansions." By W. H. L. RUSSELL, Esq., A.B. Communicated by Prof. STOKES, Sec. R.S. Received May 13, 1865. Among the papers on symbolical algebra by the lamented Professor Boole, there is one on the Theory of Development, published in the fourth volume of the ' Cambridge Mathematical Journal.' The expansion of f (x+-r- ) is there given in a very elegant form. I am desirous to ter- minate my own investigations on the Calculus of Symbols by pointing out the connexion of the binomial theorems given in my first paper on this sub- ject with the expansions due to Professor Boole, and propose with that view to expand / ( x+x^-\ in terms of — , which will be sufficient to indicate the general method. When the term of the expansion which does not contain — is known, the other terms are easily found by a method given by Professor Boole in the paper I have just mentioned. The main object of the present paper, therefore, will be to ascertain that part of the expan- sion of f (x-\-x — ) which does not contain — . \ dx) ax Putting, as usual, p for (#) and TT for x — , the expression becomes f (p +TT). Our first object must be to ascertain that part of the expansion of (P+TT)" which is independent of (TT), from whence we may easily deduce the corresponding portion of / (P + TT). Now by a former paper the part of (P + TT)", independent of TT, will be + &c. +S(w * Philosophical Transactions, 1855, p. 149. t Quarterly Journal of the Geological Society of London for May 1862. 330 Mr. W. H. L. Russell on Symbolical Expansions. [June 15, And we must first eudeavour to find a suitable expression for 2(w— r+l)2(n— r+2)S(w— r+3) . . . . 2». "With this purpose let us assume S(n_ r+i)2(ra— r+2) 2ra= A?>(n-2r+ 1) (w_2r + 2) . . . . » (»— 2r + 3) . . . . n »— 2r+4) Whence 2r This will give us 2r(2r-2)(2r— 4) 2 A'2)=(2r-l)(2r-3) 1 S '. 2r(2r-2) 2 ~ &c.=&c. A(3)_ } (r-l)(2f—2)(2r-4)....2 r (2r-2)(2r-4) 2 (2r— 1) (2r-3) 1 2r(2r-2)(2r-4)....2 1865.] Mr. W. H. L. Russell on Symbolical Expansions. 331 Hence we have generally, using II as a symbol for a continued product, whence the portion of (? + *•)" which does not contain (TT) may he written &c. -72r-m+l the general term being A£m)pr-m+1^ 2r_m+1p»; whence the part of the expansion of/(p-f TT), which does not contain TT, is + &c. If, then, we put we have + &c., the general term being A(m) where Ai.m) has the value given above ; and fi(x), /2(a;), /s(^), &c. are given by the following formula, which, as I have before said, can be immediately VOL. XIV. 2 B 332 Mr. W. H. L. Russell on the Summation of Series. [June 15, deduced from one in the paper of Professor Boole on the Theory of Development : The method of the present paper is of course of far more general ap- plication ; but I have said enough in it to explain the principle on which such expansions must be conducted. IV. " On the Summation of Series." By W. H. L. RUSSELL, Esq., A.B. Communicated by Professor STOKES, Sec. R.S. Received May 13, 1865. In a Memoir published in the Philosophical Transactions for the year 1855, I applied the Theory of Definite Integrals to the summation of many intri- cate series. I have thought my researches on this subject might well be terminated by the following paper, in which I have pointed out methods for the summation of series of a far more complicated nature. I commence with some remarks intended to give clear conceptions of the general method of calculation. In any series, . +a*ux+&c. Where a is less than unity, it is evident that we can sum the series by a definite integral when ux=J du U, \J*, ~Ul and U being functions of u, and the integral being taken between certain assigned limits. For it is mani- fest that the quantity under the integral sign then becomes a geometrical progression. Again, for a similar reason we can express by a definite integral the sum of the series -f a*uxvxwx . . . + &c., where ux =fdu 17,11*, vx = Wje=fdwW^fx> &c. Lastly, we can sum the series xwx. . . + &c. by a definite integral when 1865.] Mr. W. H. L. Russell on the Summation of Series. 333 JP +fdv'V'1V'a: &c. = &c., the number of each set of quantities ult u', &c., «lf v', &c., M^, 10', &c. being of course finite. I shall now consider the series +«W)*W+ &c- (a;) + &c., where remembering that log^ u is negative, 0 1-2V/X(J?)COS0+ 1865.] Mr. W. H. L. Russell on the Summation of Series. 335 where F(e)=r("+r^l>°"co8 { („'+ _J>) sine} . _ °ge« and \/x(x) '1S suPPose(l less ^an unity. Hence also where we render the denominator rational by multiplication, and suppose m-2 m-3 1 — 2x(#) cos md + \(x ) (x! (^) — cos /w0) 2 -f- sin2 1 irhere *(*) = ?) is less than unity, hence XiO) is greater than unity, and therefore — cos m d is always positive ; hence The general term of the series included under the signs of definite inte- gration is now of the form " belonging to a class which I have considered in my former memoir. . Let us now consider the series and ^(ar) being rational functions of ( 336 Prof. Sylvester on a Theorem concerning Discriminants. [June 15, where >//(#) must be supposed less than unity, in order that the following transformation may hold : — ( J. f' J9Q- -*) (sin 1-2 cos mO, where The remainder of the process will be evident from the two former examples. V. " On a Theorem concerning Discriminants." By J. J. SYLVES- TER, F.R.S. Received May 27, 1865. Let F(«, b, c}d)=a*d*+4a3 c+4e, y, ^)2=0 that of the conic of five-pointic contact ; and if, moreover, a, ft, y being arbitrary constants. 350 On the Sextactic Points of a Plane Curve. [June Q = (vy-wft) 9* + (wa—uy) dy + (uft-vn) 9*, then, writing as usual A=»1 Wj — w'2, . . F=v' M?' — ul u', . . the values of the ratios a : b : c :/: g : h are determined by the equations v=o, nv=°. • • Q4v=o. Now, if at the point in question the curvature of U be such that a sixth consecutive point )ies on the conic V, the point is called a sextactic point ; and the condition for this will be, in terms of the above formulae, Q5 V=0. From the six equations V=0, QV=0,... Q5V=0, the quantities a, b,.. h can be linearly eliminated, and the result will be an equation which, when combined with U = 0, will determine the ratios of x : y : z, the coordinates of the sextactic points of U. But the equation so derived contains (beside other extraneous factors) the indeterminate quantities a, ft, y, to the degree 15, which remain to be eliminated. Instead, however, of proceeding as above, I eliminate a, /3, y beforehand, in such a way that V=0, Q V=0, =0 take the form M 0 w tzti. and more generally if W=0, representing any one of the series V=0, n V=0, . . from which a, ft, y have been already eliminated, the equa- tions W=0, QW=0, n2 W=0 are replaced by ds W_dy W_dz W_ AW u v w wil' where H is the Hessian of U, or a numerical factor, and Proceeding in this way, I obtain a result free from a, ft, y in the three forms, =0, dz(wX— a-P) d2(«Y— yP) A(MX-.rP) A(wY-yP) 9x(«X-xQ) d,(>Y-7/Q) where 1865.] Destructive Distillation of the Sulphobenzolates. 35.1 X = 0r — wq, ~Y = wp — ur, Z=uq — vp, and nr2 is a numerical factor. Each of these equations is of the degree 18w — 36 in the variables ; but it is shown in the paper that they are all divisible by H, and that they further differ only in respect of the several factors u3, v3, w3. Dividing these out, the degree of the result is reduced to (18«-36)-3 (n-2)-3 (»-!)= 12/1-27, as it should be. I have riot thought it necessary to reduce the expressions completely, as the form of the result given by Professor Cayley leaves nothing to be desired, and the point specially considered here is the degree of the equation. At the same time, the redactions necessarily effected in the course of the proof of the extraneous factors are sufficient to indicate that the formulae of the present memoir would lead to an equation of the same form as that given by Professor Cayley. XL " Products of the Destructive Distillation of the Sulphobenzolates. No. I." By JOHN STENHOUSE, LL.D., F.R.S., &c. Received June 14, 1865. Preparation of Sulpholenzolic Acid. Purification of the Eenzol, As most specimens of benzol met with in commerce, even when rectified, contain impurities besides toluol and the other homologues of benzol, I have generally found it necessary to submit it to purification before using it for the preparation of sulphobenzolic acid. The commercial article boil- ing between 80° and 90° C., was mixed with about one-twentieth of its bulk of concentrated sulphuric acid, and digested for eight or ten hours in a flask furnished with a long condensing- tube. By this means a consider- able amount of the impurities contained in the crude benzol were con- verted by the acid into a black gelatinous mass similar in appearance to that obtained in the preparation of olefiant gas, a large quantity of sul- phurous acid gas was given off, and the impure benzol acquired a reddish- brown or dark purple colour. It was separated from the black mass, washed with a small quantity of water, and again heated once or twice with concentrated acid, but for a shorter time than at first, until fresh acid when heated with it ceased to become dark-coloured. In this opera- tion the benzol loses from 10 to 20 per cent., according to the amount of impurity present, and small quantities of sulphobenzolic acid are produced. Conversion of Benzol into crude Sulphobenzolic Acid. This acid may be prepared by the process given by Mitscherlich, which consists in adding benzol to fuming oil of vitriol contained in a flask, as long as it dissolves, with agitation and frequent cooling. Notwithstanding 352 Dr. Stenhouse on the Products of the [June 15, Mitscherlich's statement* that he has "succeeded as little as Faraday in combining benzol with ordinary strong sulphuric acid," I have found it advisable, when large quantities of sulphobenzolic acid are required, to treat the purified benzol with ordinary commercial acid. Concentrated sulphuric acid and purified benzol, in the proportion of about four measures of the former to five of the latter, were placed to- gether in a flask furnished with a long condensing-tube, and heated on a sand-bath for eight or ten hours. The flask in which the digestion is performed should be very large in proportion to the quantity of benzol employed, so that an extensive surface is exposed to the action of the acid f. Sulphobenzolates. The crude sulphobenzolic acid obtained by either of the above methods was separated from the uncombined benzol, and a quantity of water, about twenty times the bulk of the sulphuric acid originally employed, was added to it. This solution, which has a small quantity of sulphobenzene, C]2 II10 SO2, suspended in it, was heated to the boiling-point, neutralized with chalk, diluted with ten parts more water, and after being boiled for a few minutes, was filtered from the sulphate of calcium. The clear and slightly coloured filtrate is a solution of sulphobenzolate of calcium, Ca C6 H5 SO3, from which the salt may be obtained by sufficient concentra- tion. Sulphobenzolate of barium may likewise be prepared in a similar manner to the calcium salt, substituting carbonate of barium for chalk. The sulphobenzolates of the alkaline metals are readily obtained by pre- cipitating the solution of the calcium salt by the carbonate of the desired metal, and evaporating the solution. By this process purified benzol yielded nearly twice its weight of sulphobenzolate of sodium. The sulpho- bemolates of copper, zinc, &c., are best prepared by precipitating the solution of the barium compound by solutions of their sulphate. The copper salt is usually described in handbooks, on Mitscherlich's authority £, as forming fine large crystals. I have only been able to obtain it, whether from water or spirit, in very small crystals, which are exceedingly soluble. Decomposition of Sulphobenzolate of Sodium. The sodium-salt, after being reduced to powder and thoroughly dried, was introduced into a copper flask furnished with a bent tube, and submitted to destructive distillation, when an oily body covered with a layer of water condensed in the receiver, and a considerable quantity of carbonic and Some sulphurous acid gas were evolved, carbonaceous matter and carbonate of sodium remaining in the retort. In order that the operation may pro- ceed rapidly, and in the most advantageous manner, the quantity of sub- * Pogg. xxxi. p. 284. t A similar process has been employed by Gerhardt and Chancel in the preparation of sulphite of chlorobenzene, Compt. Kend. vol. xxxv. p. 690. \ Gmelin'8 Handbook, vol. xi. p. 150 ; Gerhardt, vol. iii. p. 72. 1865.] Destmctive Distillation of the Sulphobenzolates. 353 stance introduced into the retort should not exceed 25 to 30 grammes at each distillation. Florence flasks can be used ; but, owing to their bad conducting-power and the high boiling-point of the oil, the result is not so favourable. When the distillation is properly conducted in a copper retort, the dried sodium- salt yields from one-fourth to one-fifth of its weight of crude oil. The crude oil was separated from the supernatant layer of water, and distilled in a retort furnished with a thermometer. It began to boil at 80° C., and then rose slowly to 110° C., the distillate between these tem- peratures consisting of a small quantity of water and benzol. When the water had all passed over, the boiling-point rose very rapidly to 290° C., at which temperature the greater portion of the liquid distilled over, leaving a black tarry residue in the retort. This black residue, when more strongly heated, gave a further quantity of an oily body, which, when rectified, first yielded the substance boiling at about 290° C., and above 300° C. a liquid which on standing some weeks deposited a small quantity of crystals. The quantity boiling between 290° and 300° C. was about two-thirds the weight of the crude oil. The rectified oil between 290° and 300° C. was again distilled, when nearly the whole of it came over at 292°*5 C., the boiling-point being re- markably constant. After another rectification in a current of hydrogen, it was subjected to analysis — the carbon and hydrogen being determined by combustion with oxide of copper and a current of oxygen, and the sul- phur by ignition with carbonate of sodium and oxide of mercury. I. -603 grm. oil gave 1'708 grm. COa and -292 grm. H2O. II. '595 grm. oil gave 1'679 grm. CO2 and '288 grm. H2 O. III. -237 grm. oil gave '302 grm. sulphate of barium. IV. !275 grm. oil gave '354 grm. sulphate of barium. Theory. I. II. III. IV. Mean. C12=144 77-41 77-25 76-98 ..- .. 77-12 H10= 10 5-38 5-38 5-38 .. .. 5'38 S = 32 17-20 .. .. 17-48 17'51 17'49 186 99-99 The formula C12 H10 S, deducible from these analyses, is that of sulphide of phenyl, or a body isomeric with it. When pure it is nearly colourless, having only a very faint yellow tinge, and an aromatic but slightly alliaceous odour. It has a high refractive power, sp. gr. 1-119, and boils at 292°-5. It is insoluble in water, very soluble in hot spirit, from which it partially separates on cooling, and is miscible in all proportions with ether, bisulphide of carbon, and benzol. Its alcoholic solution, when mixed with bichloride of platinum, gives a slight flocculent precipitate, which on standing resolves itself into a reddish-coloured oil. Nitrate of silver and chloride of mercury give no precipitate. When the oil \vas treated with sulphuric acid, it dissolved in small quan- 354 Dr. Stenhouse on the Products of the [June 15, tity, forming a red solution, which, on the application of a gentle heat, changed to a fine purple colour ; this disappeared on raising the tempera- ture, the whole of the oil dissolved, and a solution was obtained of a faint greenish-black tinge. When this solution was largely diluted with water it became nearly colourless, and on neutralization with chalk yielded (be- sides the sulphate) an organic calcium-salt, very soluble in water. The solution of the oil in sulphuric acid, when very strongly heated, blackened and gave off sulphurous acid gas. Solutions of the alkalies, whether aqueous or alcoholic, appear to have no action on the oil ; but when heated with solid potash, it was decomposed with the production of compounds I am at present investigating. Action of oxidizing Agents on Sulphide of PhenyL — Sulphobenzolene. — When the oil C12 HIO S was brought into contact with strong nitric acid, a very violent action ensued, accompanied by the copious evolution of nitrous fumes. The mixture was then boiled for an hour or two with occasional addition of fresh nitric acid, and the solution thus obtained poured into a large quantity of water, when a crystalline mass of a pale yellow colour was precipitated. This, when perfectly dried, was reduced to powder and washed with ether to remove a small quantity of adhering oil, and the partially puri- fied product was recrystalhzed once or twice from benzol, and then several times from spirit, collecting apart the first portions which separate. By this means a substance in beautiful oblique prismatic crystals was obtained in a state of perfect purity, whilst in the mother-liquors there remained a large quantity of the same body mixed with a second substance crystallizing in long needles, which, however, formed but an inconsiderable portion of the whole. Although this is the method by which I first prepared the above de- scribed substance crystallizing in oblique prisms, I have since employed a process which yields it with greater facility and in a much purer state. Ten parts by weight of water, five of concentrated sulphuric acid, and two of sulphide of phenyl, were placed in a flask furnished with a long condensing- tube, and to the mixture, kept boiling, three parts of acid chromate of potassium were added in small portions at a time. The digestion continued for twenty or thirty minutes, and the mixture was then allowed to cool. The green liquid was poured off from the cake of crystals, which, after boiling with water to free it from sulphuric acid, was dried. The nearly pure substance was then crystallized, cnce from benzol and once from alcohol, when it formed brilliant crystals which were perfectlv pure. A trace of the second sub- stance previously mentioned, crystallizing in long needles, was found in the benzol mother-liquors. By this last process, which is greatly preferable to the nitric acid one, the rectified oil yielded its own weight of crystals. I. -338 grm. crystals gave '820 grm. COa and -144 grm. H2O. II. '346 grm. crystals gave '834 grm. CO2 and -144 grm. HaO. 1865.] Destructive Distillation of the Sulphobenzolates. III. -349 grm. crystals gave -844 grm. C02 and -156 grm. H20. IV. '241 grm. crystals gave -259 grm. sulphate of barium. V. -362 grm. crystals gave '385 grm. sulphate of barium. VI. -270 grm. crystals gave '293 grm. sulphate of barium. I. II. III. IV. V. 66-18 65-75 65-97 4-73 4-62 4-96 14-74 14-59 C12=144 H10= 10 S = 32 Oa = 32 218 Theory. 66-06 4-59 14-68 14-68 100-01 355 VI. 14-89 This substance was analyzed in the same manner as the sulphide of phenyl, — Nos. III., IV., V. being prepared by the nitric acid process, and Nos. I., II., VI. by oxidation with acid chromate of potassium and sul- phuric acid. The analysis of this substance leads to the formula C12 H10 SO2, which is the same as that of the sulphobenzene of Mitscherlich. It differs greatly from that body, however, both in its chemical and physical properties. I shall therefore provisionally call it sulphobenzolene. It forms oblique prisms, which are often of large size when prepared by crystallization out of benzol, in which it is rather soluble. The crystals obtained by both the processes above described were kindly measured for me by my friend Charles Brooke, Esq., F.R.S., who states they " are of the same form, the measurements corresponding exactly. They belong to the oblique prismatic system. The measurements must be considered as only approximative, the surfaces of the crystals being imperfect." No planes have been observed to determine the symbol a of the plane lal. 010 on 001 or 100 94 30 010 TOO 8530 010 lal 108 20 001 TOO 110 20 It is very soluble in hot spirit, from which it separates on cooling in a manner closely resembling the crystallization of chlorate of potassium. It is also soluble in ether, bisulphide of carbon, and slightly in boiling water, crystallizing out completely on cooling. It melts at 126°C., and distils at a much higher temperature. Sulphobenzolene dissolves readily in concentrated sulphuric acid, and is not decomposed even when the solution is heated to the boiling-point. VOL. XIV. 2 D 356 Dr. Stenhouse on the Products of the [June 15, Water precipitates the substance unchanged. Aqueous solutions of the alkalies appear to have no action on the crystals ; but when they are heated with solid potash a powerful reaction takes place, with the production of new compounds. When sulphobenzolene is digested for some time with a mixture of con- centrated nitric and sulphuric acids, it dissolves, and red fumes are evolved. If a large quantity of water be now added to the mixture, a copious pre- cipitate is obtained, difficultly soluble in hot alcohol, from which it crys- tallizes in minute needles. Decomposition of Sulphobenzolate of Calcium. When this salt was distilled in the manner described for the sodium compound, it underwent a similar decomposition — water and oil collecting in the receiver, and carbonic and sulphurous acids being evolved. In this instance, however, a very high temperature was required, and the quantity of oil obtained was much smaller than from the sodium-salt, being only about one-sixteenth the weight of the dry sulphobenzolate of calcium employed. The crude oil, when rectified, commenced to boil at 80° C., between which and 1 1 0° C. small quantities of water and benzol came over. The boiling-point then rose rapidly to 280° C., between which temperature and 300° C. about one- fifth of the original quantity of oil came over. Above 300° C. the distillate obtained became almost solid on cooling, con- sisting apparently of the same crystalline body of which a small quantity only was obtained in the rectification of the crude oil from the sodium-salt. The portion distilling between 280° and 300° C., when submitted to the action of sulphuric acid and acid chromate of potassium, yielded a crystal- line cake, which, after washing, was dissolved in hot benzol ; on cooling, a few oblique prismatic crystals of sulphobenzolene were obtained, and like- wise a large quantity of the needle-formed crystals, probably held dissolved in the oil previously to its being oxidized. These I am at present examining. Decomposition of Sulphobenzolate of Ammonium. This salt, which melts at about 200° C., is decomposed with great facility, and at a comparatively low temperature, yielding large quantities of bisul- phite of ammonium and benzol, with some undecomposed sulphobenzolate of ammonium, and likewise a very small quantity of a crystalline substance slightly soluble in cold water, the only residue in the retort being a little carbonaceous matter. On rectifying the benzol obtained in this decom- position, a small quantity of a heavy oil was obtained, having a high boiling- point, and which deposited crystals on cooling. When oxidized, sulpho- benzolene seems to be formed in small quantity. Sulphobenzolamide. The crystalline substance which occurs in small quantity, amounting to about one and a half per cent., among the products of the destructive dis- 1865.] Destructive Distillation of the Sulphobenzolates. 357 tillation of sulphobenzolate of ammonium, is washed with cold water to free it from the ammonium salts with which it is accompanied, dissolved in boiling water, and filtered to separate it from adhering traces of oil. On the cooling of this solution, the impure sulphobenzolamide is deposited in large micaceous scales. By one or two crystallizations out of spirit, and one from boiling water, it is obtained perfectly pure and white. I. '350 grm. II. -442 grm. III. '343 grm. IV. -237 grm. V. -252 grm. VI. -432 grm. VII. -124 grm. Theory. I. C6=72 45-85 45-98 gave -590 grm. CO2 and -144 grm. H2O. gave -740 grm. CO2 and '182 grm. H2O. gave -219 grm. platinum. gave '148 grm. platinum. gave '376 grm. sulphate of barium. gave '645 grm. sulphate of barium. gave -186 grm. sulphate of barium. II. H7= 7 N=14 4-46 8-92 4-57 4-57 III. IV. 9-03 8-84 V. VI. S =32 20-38 O.2=32 20-38 157 99-99 VII. Mean. 45-82 4-57 8-93 20-46 20-48 20-58 20-51 20-17 100-00 These analyses correspond to the formula C6 H7 NSO2, which is that of sulphobenzolamide, equivalent to sulphobenzolate of ammonium minus one atom of water, C*H* 1 S03-H20=C6H7NSO2. NH4 J Sulphobenzolamide crystallizes in large and very lustrous micaceous scales, greatly resembling naphthalin in appearance. It fuses at 153° C., and recrystallizes on cooling ; when more highly heated, it volatilizes. It is extremely difficult to reduce the dry crystals to powder, owing to their toughness. When boiled with a strong solution of potash it gives off ammonia, sulphobenzolate of potassium being apparently formed at the same time. Weak acids have little or no action on it. The analyses were made for me by my assistant, Mr. C. E. Groves. XII. " An Account of the Base-observations made at Kew Observa- tory with the Pendulums to be used in the Indian Trigonome- trical Survey." By BALFOUR STEWART, F.H.S., and B. LOEWY, Esq. Received June 15, 1865. [This Paper will he puhlished in a suhsequent Number.] VOL. XIV. 358 Dr. Richardson on the possibility of [June 15, XIII. " An Inquiry into the possibility of restoring the life of Warm- blooded Animals in certain cases where the Respiration, the Cir- culation, and the ordinary manifestations of Organic Motion are exhausted or have ceased." By BENJAMIN WARD RICHARDSON, M.A., M.D. Communicated by Dr. SHARPEY. Received June 14, 1865. The present memoir presented to the Royal Society is preliminary ; it does not profess to do more than to open the way to new work, and to show the reasons why the restoration of action, in cases where life is suspended, is at present so doubtful and difficult. In the course of my inquiries I have not confined myself to the mere question of treatment as applied when there are still faint indications of spontaneous animal action, or when such action has ceased only for the moment. It is true that many of the experiments related in this Paper have reference, incidentally, to treatment under the circumstances named ; but I have had actually in view a much wider research. I have asked, When an animal body that has undergone no structural injury (that is to say, no destruction of organ or tissue) has ceased to exhibit those actions which indicate what is commonly called life, why may it not be restored at a period previous to the coagulation of the blood in its vessels, if not pre- viously to the period when the new chemical changes, developed under the form of putrefaction, are established ? To render the memoir concise, I have divided it into two parts. One of these parts contains nothing more than the details of experiments, the ex- periments being classified in groups according to the object for which they were performed. It is my desire that this record should be preserved for reference in the Archives of the Society. The other part, which is here published, consists of an analysis of the experimental evidence, with the conclusions to which I have been led by the evidence. ANALYSIS OF THE EXPERIMENTAL EVIDENCE. In the experimental inquiry all the animals operated upon had been sub- jected to such means for suspending their animation as produced the least possible amount of change in the structure of organs. The animals were all healthy while living. To suspend the spontaneous action which they presented, and which marked their life, chloroform was employed in the large majority of cases ; but in some instances carbonic acid was used, and in others the process of drowning. The readiness with which chloroform can be employed, and the painless- ness to the subject which is implied in its use, recommended this agent specially at first. As the inquiry has proceeded I have seen no reason, so far, to introduce any modification, inasmuch as the continuance of experi- ment and repeated observation have simply tended to indicate that the pro- cess called " death " is unity ; and that if animal action, brought to a stand by chloroform, could be reproduced by any process, the same restorative 1865.] restoring the Life of Warm-blooded Animals, fyc. 359 process would be applicable after every other kind of suspension that was unattended by mechanical injury of structure. Throughout the inquiry I have kept steadily in view a process for resto- ring the development of force which is constantly and successfully being performed. A simple process enough ! I mean the relighting of a taper. I see in the taper as it is burning the analogue of living action. The com- bustible substance having the force stored up in it circulating through the wick as through so many vessels, becoming distributed in the presence of incandescent heat so as to combine with oxygen ; then itself liberating force, burning, and in the process showing spontaneous action, the analogue of living action. From this analogy I gather, further, that if I could set the blood burn- ing as it burns in life, after its natural combustion has been suspended, I should relight the animal lamp, and that the redevelopment of force in the form of animal motion, which is life, would be reestablished. But how in the case of the animal body is the light to be applied ? That is the difficulty. Suppose that the taper or the fire were known only to us from their spontaneous manifestations, would the task to restore their burning if that had gone out be less difficult ? What philosophical process should we adopt? We should first most naturally take fire from fire when that were possible. But how, when that were not possible, should we pro- ceed to obtain the spark for kindling that which we might well know would burn spontaneously after kindling, the proper conditions being supplied ? In such case we should most naturally look for the process by which fire is spontaneously exhibited, and we should discover it in the friction of one body with another ; in the friction of stone, for example, with iron. Straightway we should imitate this and produce fire, and know how to renew and perpetuate it. Again, in our observation of burning bodies we should see often that a point of flame well-nigh extinguished would rekindle under a little addi- tional friction of air, or an additional communication of matter that would burn, and we should acquire an art of sustaining fire by these measures. Lastly, as we went on observing we should discover that the force elicited in the combustion could be so applied as to set in motion almost endless mechanism ; and we should learn, as we have learned, that however com- plicate the mechanism, however numerous its parts, it takes all its motion from the fire. The physiologist who would distinguish himself by learning the art of resuscitation must, I have thought, place himself precisely in the same condition as the primitive man who, in the matter of ordinary combustion, would pass to the civilized man through the phases I have described ; and it seems to me that, so far as we have progressed we have become acquainted with three natural steps in the inquiry at least. We have discovered that when the animal fire ig declining from want of air, it may be fanned into 2E2 3GO Dr. Richardson on the possibility of [June 15, existence again by gentle friction of air. We have learned hy an experi- ment, first thoroughly demonstrated before the Royal Society in the early days of its remarkable history, that when the animal fire is waning, owing to deficiency of fuel, that is to say, of blood, it may be revivified by the direct introduction of new blood. Lastly, we have learned that the natural or spontaneous combustion of blood is due to the affinity of the oxygen of the air for combustible substance in the blood, when such substance is pre- sented to the air over a sufficient extent of surface. These observations may be received as demonstrable truths ; and to them may be added an inference which amounts nearly to a demonstration, though all its elements have not yet been estimated — that the motion of the animal (the action of its mechanical parts) is produced by the force evolved in the process of combustion. The experiments submitted in this paper have reference to the best means to be adopted for fanning into active life the animal fire that is expiring but is not suspended. But they extend also to the deeper questions, whether animal combustion cannot be reestablished when it appears to have been extinguished ? and whether so-called vital acts would not be spontaneously manifested upon such reestablishment of animal combustion ? In the part of this paper which contains the details of experimental research, the experiments are classified in three series. The first series of experiments has reference to attempts made to pro- duce combustion of blood in the lungs by the introduction of air — Artificial Respiration. The second series embraces experiments in which attempts were made to induce circulation of the blood by physical operations — Artificial Circu- lation. The third series supplies the records of experiments in which the effects of an increased temperature upon the body were observed. FIRST SERIES OP EXPERIMENTS. — Artificial Respiration. Effects of simple inflation of the lungs with air. — The first series of ex- periments, those in which artificial respiration was employed, exhibits, I believe faithfully, the precise value of artificial respiration. In the preli- minary inquiries, the animals, having ceased to breathe, were immediately subjected to artificial inflation by means of double-acting bellows. The result in every case was, that whenever the action of the heart had come to rest, the temperature of the air employed being at various degrees, from 40° to even 120° Fahr., no reaction followed the inflation. In opening the bodies of animals thus treated, the lungs were invariably found empty of blood, and in a large number of cases emphysematous, while the right side of the heart was filled with fluid blood. The heart continues to beat when artificial respiration restores. — In one striking experiment, where respiration had entirely ceased and no action of the heart could be detected from pulsation, a recovery took place in a dog. 1865.] restoring the Life oj 'Warm-blooded Animals ,fyc. 361 Narcotism was again carried on to the same extremity, with recovery on inflation ; and this was repeated once more with the same result. But in this experiment, although, to appearance, animal action was entirely sus- pended, a minute examination of the heart, through an opening in the skin sufficiently large to allow the mouth of the stethoscope to rest on the ribs, but not to injure either them or the intercostal muscles, proved that there was still sufficient action of the heart to produce a faint first or systolic sound. Cessation of the heart during artificial respiration. Order of cessation. — These experiments by inflation were modified. So soon as the animal ceased to exhibit evidence of life, the artificial respiration was set up, the chest-wall was removed, and the effects of the artificial respiration on the heart were observed. In every case where the operation was performed within five minutes the heart was discovered pulsating. The action was uniformly best marked in the right auricle, next in the right ventricle, next in the left auricle, and next in the left ventricle. Contraction remained longest also in the same order. But it was observed uniformly that the contraction of the right ventricle never sufficed to fill the pulmonary artery with blood so as to reestablish the pulmonic circuit. Effect of inverting the body. — In one case the animal was suspended with the head downwards while the right ventricle was contracting vigo- rously. In this case blood passed into the pulmonary artery and faintly coloured the surface of the lung, which was previously pale ; but the pul- monic circuit was not reestablished, and after death the capillaries were found to be obstructed mechanically from coalescence of the blood- corpuscles. Effects of artificial inflation with air raised in temperature. — These ex- periments with the chest laid open were varied by the employment of air at different temperatures. The evidence was clear that when the contrac- tions of the heart were failing, an increase in the temperature of the air to 140° Fahr. caused a more vigorous action, which often lasted from five to ten minutes. Effect of exposure to the air in exciting cardiac action. — To determine whether the act of insufflation of air at a mean temperature of 60° was sufficient of itself to set up contraction of the heart, two animals were de- stroyed with chloroform and allowed to rest fifteen minutes. Then in one animal artificial respiration with air at 60° was employed for five minutes, and the hearts of both animals were immediately exposed to view. There was no action in either case at first ; but after exposure to the air for a few minutes the right auricle in both hearts commenced to contract, and the ventricles followed. But the action was in no way more determinate in the animal that was receiving air by inflation than in the other animal. I notice this point particularly, because some experimentalists, who have made but one or two observations, on seeing the heart pulsate during artificial respiration, have conceived that the phenomenon was due solely to the in- 362 Dr. Richardson on the possibility of [June 15, flat ion. I believe it myself to be due to the action of the external air, which at a moderate temperature gives up a little oxygen to the blood in the walls of the heart, by which some heat is evolved and therewith motion is exhi- bited. My reasons for this view rest on the facts that a current of air at 35° Fahr., brought to bear on the heart, at once stops the action, while another current above 60° restores it, and that a little vapour of chloroform or of ammonia blown upon the heart— both of which agents stop oxidation — im- mediately arrests the action, which returns, at a sufficient temperature, when these agents are lost by diffusion. I believe also that the right auricle is last to die, because its thin walls allow the passage of oxygen to venous blood on their interior, since on washing out the auricle thoroughly with water, or on applying to it a substance which prevents oxidation, the auricular motion at once declines. These remarks on the effect of artificial respiration in relation to the motion of the heart, do not apply with the same force when the air em- ployed for inflation is heated to 1 20° Fahr. ; then even fifteen minutes after death, if the inflation be sustained, the heart is found contracting as the chest is laid open, the action really being sustained by the diffusion of heat from the lungs to the heart ; but the action excited is insufficient to produce a pulmonic current. Effects of other gases used in artificial respiration. — The experiments were further modified by using for insufflation other gases in place of com- mon air. Oxygen was thus used, oxyhydrogen, ozone, and air containing 0'20 per cent, of chlorine. With two exceptions, the same observations are applicable to these experiments as were made in reference to those with common air. As a rule, the gases possessed no action on the heart to restore the pulmonic current when the natural action had been arrested. The exceptions were, that when the action of the heart was still feebly pro- ceeding, respiration not being suspended, the air containing chlorine or ozone produced a quicker restoration, the ozone being much the less objec- tionable in regard to its after-effects. Artificial respiration by electro-galvanic action. — The experiments on artificial respiration were finally modified by using the electro-galvanic cur- rent to excite the muscles of respiration so soon as natural respiration and circulation had ceased. By inserting a fine needle, insulated except at the point, into the larynx of an animal, and the other needle into the diaphragm, and by regulating the shock by means of a metronome, so that a given num- ber of shocks representing the respirations of the animal are administered, the most perfect appearance of natural respiration may be sustained for so long, in some cases, as seven minutes ; and the phenomena are often re- markable, and to the inexperienced deceptive. Thus, owing to the action on the vocal apparatus, a rabbit will scream as loudly as in life ; and, lying breathing and screaming, might well be considered to be alive. But all the while the heart is at rest, if it have once rested, and on opening the chest the lungs are found bloodless. 1865.] restoring the Life of Warm-blooded Animals, fyc. 363 Resume". — Value of Artificial Respiration. Reviewing the whole series of experiments, I am led to the conclusion, and I think it admits of direct demonstration, that artificial respiration, in whatever way performed, is quite useless from the moment when the right side of the heart fails in propelling a current of blood over the pulmonic circuit, and when the auriculo-ventricular valve loses its tension on contrac- tion of the ventricle. Break of blood-column. — At this point the blood-column is broken : the resistance to the passage of blood is of itself almost overwhelming, while the muscular action is decreasing in power in proportion as the difficulty of propulsion is increasing. Obstacle from coalescence of blood-corpuscles. — Another obstacle is in the blood itself. It consists in the rapid coalescence of the blood-corpuscles as the motion of the blood ceases. This is so determinate, that within three minutes after its complete cessation, the blood, though still fluid, often fails to be carried, even by a moderately strong stroke, over the lungs. In one experiment the chest of a strong dog was laid open while the animal was under chloroform, and artificial respiration was sustained. Both sides of the heart were acting vigorously, and there was a good arterial current. In the midst of this action, which could easily have been sustained for an hour, the pulmonary artery was suppressed for the space of two minutes and fifty seconds. Then it was liberated, and the ventricle, which was still beating vigorously and gave out a valvular sound, carried the pent-up column into the pulmonary vessel ; but there was no circuit. The lung was somewhat congested, and the capillaries were blocked up so as to resist an impulse which, increased by galvanism, was more active for some minutes after the liberation of the artery than it had been previously. Obstruction from coagulation of blood. — The last obstruction is the co- agulation of the blood ; but as this does not, as a general rule, occur (in cases where the blood-vessels are not opened) within twenty minutes, and often not within an hour, it may be considered a secondary difficulty, though naturally fatal to success, according to our present knowledge, when it has taken place. Modes of applying Artificial Respiration. Regarding the modes of applying artificial respiration, and the time, the facts are briefly as follows : — 1. It is unnecessary and even injurious to employ it so long as there is any attempt at natural respiration*. 2. Before employing it, the patient should be placed with the head slightly lowered, a position which will largely assist the right ventricle in any feeble effort it may be making to propel a current of blood into the pulmonic circuit. 3. It is of the greatest importance that the air conveyed into the lungs * On this poi'it see observations 20 and 21 in the Experimental Part. 364 Dr. Richardson on the possibility of [June 15, should be at a temperature above 60° ; air below that temperature should never be used. 4. All violent attempts to introduce large quantities of air are injurious ; for whenever the pressure of the blood from the right side of the heart is reduced, the danger of rupturing the air-vesicles by pressure of air is in- creased. In a word, the practitioner should remember that he is doing the same act, virtually, in artificial respiration, as he is when attempting to relight an expiring taper. Any violence will only disarrange the mechanism, and turn the last chance of success into certain failure. 5. So long as care be taken to sustain a gentle action of respiration, it signifies little, in my opinion, what means be employed. I have found a double-acting bellows, described in the experimental part of this paper, answer every purpose fairly. If any philosophical-instrument maker could invent a good and portable electro-magnetic machine with my metronome principle applied to it, so that from fifteen to twenty shocks per minute could be passed from the larynx to the diaphragm directly, the most per- fect attainable artificial respiration would be secured so long as any mus- cular irritability remained ; and I should suggest the value of such an in- strument in cases where it could be brought into operation immediately after natural respiration has ceased. In combination with air heated from 120° to 140° for inhalation, every possible advantage that could accrue from artificial respiration, or rather from respiration artificially excited, would be secured, the persistence of muscular irritability being at the same time a sure index that the effort should not cease. Note on Receiving-houses for the Drowned. The observations I have made in respect to the influence of heated air lead me to suggest that, in all receiving-houses for those who are apparently dead, a room should be set apart the air of which should be at 140° in summer, and 130° in winter. If bodies taken out of the water showed any indications of breathing, it would be sufficient, in my opinion, to place them in such an atmosphere, simply providing by the position of the body for the escape of water from the lungs. There would be under such con- ditions quick evaporation of water adhering to the bronchial surface, while the warm air would quicken the respiration, encourage the action of the heart, and prevent radiation of heat from the body. If artificial respira- tion were considered necessary, its performance in such an atmosphere would render the possibility of recovery far greater than if a low temperature and a moist state of atmosphere prevailed. SECOND SERIES OF EXPERIMENTS. — Artificial Circulation. In the second series of experiments an attempt was made by various physical means to restore the circulation ; these attempts may be called attempts at artificial circulation. Various processes were adopted. In one class of inquiry oxygen was gently infused into the circulation, either in the form of gas, or in solution as peroxide of hydrogen, in order to see 1865.] restoring the Life of Warm-blooded Animals, §-c. 365 if by this means the heart could be stimulated to active contraction. In other instances water heated to a given temperature was injected, or the vapour of water. Again, electricity was brought into play ; and, lastly, various mechanical contrivances were introduced, either for forcing the blood over the system or for drawing it over. Injection of oxygen.— In. respect to the effect of oxygen gas, I found that when the gas freshly made from chlorate of potassa, but well washed, was driven into the venous current towards the heart by the vena cava su- perior, the auricle and ventricle of the right side at once exhibited active contraction, which could be prolonged for an hour without difficulty by simply continuing the introduction of the gas at intervals ; but the contrac- tion of the ventricle was never sufficient to produce a pulmonic current. When the gas was injected into the arteries, the current being directed towards the heart, so as to charge the structure of the heart itself with the gas through the coronary arteries, the heart in one instance made active movements which could be distinctly felt through the chest wall ; but the effect was only momentary ; and after it was over, the organ was found distended with gas and devoid of irritability. In another case, on making a post-mortem examination of an infant that had been dead twelve hours, oxygen gas at a temperature of 96° was injected into the heart. The organ became gradually distended ; and on the left side, both in the auricle and in the ventricle, tremulous muscular action, like very feeble contraction, was distinctly seen. Whether this was due to the mechanical entrance of the gas or to true muscular contraction excited by the presence of the gas, is perhaps open to question, but I could make no distinction between this contraction and ordinary contraction as it is elicited immediately after death. The subject of this experiment was fourteen days old. Previous to the in- jection there had been no cadaveric rigidity, but after the injection this phenomenon was well marked. Injection of peroxide of hydrogen. — The experiments with the peroxide of hydrogen were varied by passing the solution very slowly into the lung through the trachea, so that the oxygen that would be liberated might come into contact, together with the air afterwards introduced by the bellows, with any blood remaining in the pulmonic circuit. A little fluid during this process found its way into the left auricle through the pulmonary veins, and the auricle thereupon contracted. On injecting the peroxide, in another experiment, over the arterial system, the blood on the venous side was pushed forwards into the heart and it was made red in colour from absorption of the oxygen. As the fluid found its way round the systemic circuit, vigorous muscular contraction of the pectorals, of the muscles of the neck, and of the diaphragm followed, but there was no reaction of the heart. Oxygen excites muscular action. — I gather from these researches that oxygen, introduced into the circulation directly, possesses the power of calling forth muscular contraction. This power seems to be due to the combination of the oxygen with a little blood remaining in the circulatory 366 Dr. Richardson on the possibility of [June 15, channels, and to the evolution of force from that combination. The effect of the oxygen, therefore, is extremely limited ; and when introduced in the gaseous form, the distention it produces leads to a certain degree of disor- ganization of structure. I do not at this moment see therefore that oxygen admits of being applied as a direct excitant of the heart ; but it is worthy of remembrance that the element produces temporary excitability when diffused through muscular structure recently rendered inactive. Heat as a restorer of the circulatory power. — A large number of attempts were made to restore the circulation by means of heat conveyed into the vessels by heated fluids. The phenomena produced were very remarkable, and they have engaged my attention for more than five years. I first observed that when vapour of water (steam) at a temperature of 1 30° was driven into the arteries, there was at once rapid and general mus- cular action, the heart participating in the movement, but less actively than the voluntary muscles. Injection of heated water. — I afterwards used simple water for injection heated to various degrees, from 96° to 130°. When water is thus injected, the animal being only a few minutes dead, and the water not being below 115° Fahr., the extent and activity of the muscular contractions are even more marked than when galvanism is brought into action, but in the greater number of cases the effect of the warm water ceases in from fifteen to twenty minutes. When the temperature of the air in which the animal lies is below 40°, the water will act for so long a period as three hours after death. The water ceases to exert its influence when it infiltrates the cellular tissue. The admixture of salt with the water, so as to raise the specific gravity to the natural specific gravity of the blood, unquestionably diminishes the effect of the heated water ; the muscular contractions are less rapid and less prolonged, although the infiltration into the cellular tissue is prevented for a much more lengthened period of time. I attribute the action produced on the muscles entirely to the heat evolved by the water. Injection of blood*. — Injection of blood held fluid by alkali, oxidized and heated to 96°, was employed. The blood was injected into the carotid in the direction of the heart, the object being to fill the coronary arteries with the fluid. This intention was fully carried out ; but although the animal had been only a few minutes dead, there was no response on the part of the heart. In another experiment, blood from the sheep, defibrinated, thoroughly oxidized, and warmed to 115° Fahr., was injected into the arterial system im- mediately after the death of an animal (a rabbit that had been destroyed by chloroform). The right auricle having been opened to allow of the escape of venous blood, no difficulty was experienced in forcing over the oxidized blood, and it returned freely by the veins ; but it did not excite the least contraction. When this transfusion had been carried on some minutes, the blood was replaced by water at 125° Fahr. Immediately as the water found its way round the body, vigorous action of the body was * See note, p. 369. 1865.] restoring the Life of Warm-blooded Animals, fyc. 367 manifested, with facial movements extremely like life ; and these move- ments, by repeating the injection, were sustained for an hour. This expe- riment shows that heat alone was the restorer of the muscular irritability. Electricity as an excitant of the circulation. — Electricity, in the form of electro-galvanism, was employed in several experiments and in various ways to excite the heart. The little battery of Legendre and Morin, with the addition of the metronome so as to regulate the stroke, was the instru- ment used, and artificial respiration was combined with the electric process. In one experiment the negative pole from the battery was passed along the inferior cava into the right side of the heart, and the opposite pole, armed with sponge at its extremity, was placed over the heart externally. Suffi- cient action was excited to produce a pulmonic current by the contraction of the right ventricle. The left side of the heart also contracted on receiv- ing blood, an arterial circuit was made, and the animal exhibited for the moment all the signs of reanimation. In another case the insulated pole from the battery was passed into the left side of the heart of a dog, the opposite pole being placed on the divided chest-wall. There was immediate action of all the muscles of the chest, but the heart was uninfluenced. In a third case a current was passed from the brain along the whole length of the spinal column, and artificial respiration was sustained for half an hour. On opening the body, the heart was found full of blood on both sides and was contracting, but not with sufficient force to produce a circuit. In a fourth case, a dog being the subject of experiment, electric com- munication between the right side of the heart and the external part of the organ was set up with artificial respiration, as in the first experiment of this kind, only that the poles were reversed, and at the beginning of the experiment the pole applied ultimately to the heart externally was placed for a few minutes previously over the intercostal muscles. In this experi- ment the heart did not respond at all, although the thoracic muscles made vigorous contractions. The inference which I draw from these experiments with electricity on the heart is, that by rapidly establishing a direct circuit between the blood in the right side of the heart and the external surface of the organ, using a moist conductor from the positive pole for the external surface, a sufficient contraction may (I had almost said, by a fortunate accident) be induced in the right ventricle to drive over the pulmonic current of blood, and to allow of its oxygenation by artificial inflation of the lungs. This fact at first sight looks small ; but I value it beyond measure, because it has demon- strated that, when the action of the heart has ceased, the chest of the ani- mal being open and all the conditions for reanimation being most unfa- vourable, the mere passage of blood from the right to the left side of the heart is sufficient to reestablish the action of the left side ; that the left side thus reacting can throw a blood-current into the arteries ; and that upon the reception of blood by the system, general muscular action and rhythmical action of the muscles of the chest are reproduced. 368 Dr. Richardson on the possibility of [June 15, Advantages and dangers of galvanism. — la considering the advantages that may be derived from galvanism, certain dangers of it must not be for- gotten. My experiments clearly showed that the natural muscular irrita- bility, while it is for a short time made more active by galvanism, is shortened in duration. This is natural. The irritability of muscle is in proportion to the degree of force which remains in it after the blood is withdrawn, which force is evolved in proportion as it is called forth. It is well, there- fore, in applying galvanism for any purpose to the subject in whom the action of life is suspended, to use the agent for one definite object, and to remember that, in proportion as it is used, its power for good di- minishes. Mechanical methods for restoring the circulation. — In the last division of the physical series of experiments, the object held in view was to set the blood mechanically in motion through its own vessels. The attempts were made (a) by forcing blood towards the right side of the heart and into the lungs by the action of a syringe fixed in a vein, (b) by trying to draw over a current of blood into the arteries from the veins and over the lungs, (c) by trying to inject the heart of one animal with blood derived from another animal. Forcing-action by the veins. — A priori it seems an easy task to take an animal so soon as it is dead, to fix a tube from a syringe in the external jugular vein, to fill the syringe with blood, and by a downward stroke to push on the blood in the course of the circulation. From a mechanical point of view, the operation is perfect in theory ; and when we remember that the auriculo-ventricular valve of the right side becomes in fact a natu- ral valve for the piston, it is difficult to see how an artificial circulation can fail to be established by this simple means. When we further remember how easy it is to combine artificial respiration with the propelling process, one must feel that, prior to a point of time when the blood has coagulated, the process ought to succeed. Indeed, when the suggestion first occurred to me, I was so struck by it, that I rose from bed in the middle of the night to carry it out. Without for a moment losing faith in it, it has not as yet, however, been successful in my hands. The practical difficulty lies in the adjustment of the force employed. If too much force be used, the vein gives way ; if too little, the obstruction in the pulmonary artery and lungs is not overcome. In further researches I shall employ larger ani- mals than I have done up to the present time. Suction-action by the arteries. — While conducting this forcing-process for artificial circulation, another idea suggested itself, viz., that perhaps it would be possible to draw a current of blood over the lungs into the arte- ries, oxidizing the current as it passed by artificial respiration. With this object in view, a syringe, connected with an air-pump, was fixed in a large artery, and the barrel of the syringe was then exhausted. When the syringe was thus filled with blood, the motion of its own piston downwards pushed the blood back into the arteries in the directiou of the heart. The 1865.] restoring the Life of Warm-blooded Animals ,fyc. 369 difficulties in this experiment were connected with the rapid coagulation of blood ; but here, as in a previous experiment, sufficient was indicated to prove that reanimation is a possible fact. In one case the syringe was filled with blood, brought over the lungs and oxidized ; and when this blood was driven again over the arterial circuit into the muscles, it reestablished, wherever it found its way, muscular action, and, for a brief period, all the external phenomena of life. Transference of motion from living to dead hearts. — Equally interesting with the results just named were those in which it was attempted to stimu- late to contraction the dead heart of one animal with the force derived from the blood issuing from the heart of a living animal. In the experi- ment related as bearing on this point, although the force could not be readily conveyed by the pulsating stroke of the living heart, it was shown that twenty-eight minutes after the dead heart had ceased to pulsate, its contractions were revived by the transference of the blood derived from the heart of the animal that lived. Artificial blood for injection. — It remains to be seen whether a fluid resembling arterial blood, and capable either of being readily compounded when required, or of being kept ready for use, and capable also, when heated to 98°, of restoring the muscular power of the heart, may not be invented. If it can, then the operation of injecting the heart by a carotid or brachial artery will be the most important practical step yet made towards the process of resuscitation when the motion of the heart has been arrested. Value of the heart-stroke. — Granting, however, that such a fluid could be discovered, it would be necessary, in using it, to feed the heart, not in one continuous stream, but stroke by stroke, as in life ; for it seems to me that the stroke supplements or, more correctly speaking, represents a cer- tain measure and regulation of the force derived from the combustion of the blood. After many failures, I believe I have at last contrived an in- jecting-apparatus which will supply the stroke at any tension and at any speed that may be required ; but the instrument is not yet out of the maker's hands. Bearing on this subject, it is certain that blood at 98° in the living heart will excite spontaneous action of involuntary muscle ; that blood which has been drawn, oxidized, and heated even to 115° will not excite sponta- neous muscular action when injected in a continuous stream, but that water or blood at 1 25° injected with a continuous stroke will excite. It is essential, therefore, to determine whether the addition of mechanical force by stroke will supplement the necessity of a higher temperature*. * Since this paper was laid before the Society, I have determined by a direct experi- ment that rhythmic stroke is of the first importance in restoring muscular contraction. By means of a machine which can either be worked by the hand or by electro-magnetism, I was enabled, assisted by my friends Drs. Wood and Sedgewick, to introduce blood heated to 90° Fahr. into the coronary arteries of a dog by rhythmic stroke, and at the 370 On restoring the Life of Warm-blooded Animals, fyc. [June 15, THIRD SERIES OF EXPERIMENTS. — Application of External Heat. The last series of experiments were conducted to ascertain the effects of external heat applied to the hody that has ceased to show evidence of life. I was led to the inquiry hy the fact that a kitten that had heen under water, to my direct knowledge, for two hours, became reanimated in my pocket, and lived again perfectly. To see what further could be done in this direction, I placed three young rabbits, which had been drowned, in a sand-bath at temperatures respectively of 100°-110° and 120°. Afterwards other rab- bits that were destroyed by carbonic acid and chloroform were placed in the same manner and exposed to the raised temperature for an hour. In no case was there any restoration of vitality ; but it was observed that those parts of the body that had been more directly exposed to the heat showed the earliest indications of cadaveric rigidity. In the experiments where the death took place from chloroform, and where the animals had been exposed to a temperature of 100°, the heart at the end of an hour was found still excitable, and on the right side was contracting well without the application of stimulus. This did not occur in the cases of death from drowning and carbonic acid, nor yet in cases where the warmth was carried above the natural temperature. These observations are of moment as in- dicating two facts, — viz., that chloroform is less fatal as a destroyer of mus- cular irritability than either carbonic acid or the process of drowning ; and that in the application of temperature to the external surface of the body by the bath, it is not advisable to raise the temperature many degrees above the natural standard. It is worthy of remark that in one of the rabbits which had been de- stroyed by chloroform and exposed to a temperature of 100°, the muscular irritability in the intercostal muscles was present thirteen hours after death. In all the cases the right side of the heart was found free of engorgement, while the left side and the arteries contained blood — thus indicating that a pulmonic current had been produced. GENERAL CONCLUSIONS AND INDICATIONS. I have already shown that artificial respiration is of service only when blood from the heart is being still distributed over the capillary surface of the lungs — or, to return to the simile with which I set out, that the process is simply one of fanning an expiring flame, which once expired will not, in spite of any amount of fanning, relight. The further conclusion to which I am at this moment led, goes, however, beyond the process of artificial respiration ; returning again to the simile, I venture to report that, even same rate as the stroke of the heart of the animal previously to its death. The result was, that one hour and five minutes after the complete death of the animal, its heart, perfectly still, cold, and partly rigid, relaxed, and exhibited for twenty minutes active muscular motion, auricular and ventricular. The action, which continued for a short time after the rhythmic injection was withheld, was renewed several times hy simply reestablishing the injection. 1865.] Mr. Bastian — Anatomy and Physiology of Nematoids, 871 when the heart has ceased to supply blood to the pulmonic capillaries, during the period previous to coagulation, the blood may be driven or drawn over the pulmonic circuit, may be oxidized in its course, may reach the left side of the heart, may be distributed over the arteries, and that, thus distributed, it possesses the power of restoring general muscular irritability and the external manifestations of life. Hence I infer that resuscitation, under the limitations named, is a possible process, and that it demands only the ele- ments of time, experiment, and patience for its development into a de- monstrable fact of modern science. Various modifications of the experiments to which I have had the honour to draw the attention of the Society are in hand ; and if I am allowed the privilege, they will form the subject of another communication. XIV. " On the Anatomy and Physiology of the Nematoids, parasitic and free; with observations on their Zoological Position and Affinities to the Echinoderms." By HENRY CHARLTON BASTIAN, M.A., M.B. (Lond.), F.L.S. Communicated by Dr. SHARPEY. Received June 13, 1865. (Abstract.) After commenting upon the many conflicting statements which have been made concerning the anatomy of these animals, and more especially with regard to the presence or absence of a nervous system, and of real organs of circulation, the author alludes to the increased interest which has lately been thrown over this order by the discovery of so many new species of the non-parasitic forms, marine, land, and freshwater. He has entered fully into the description of the tegumeutary organs, and has recognized a distinct cellulo-granular layer intervening between the great longitudinal muscles and the external chitinous portion of the integument. This layer is one of great importance in the economy of these animals ; the author looks upon it as the deep formative portion of the integument from which the chitinous lamellae are successively ex- creted. It is bounded internally by a fibrous membrane, which serves as an aponeurosis for the attachment of the four great longitudinal muscles ; and the well-known lateral and median lines which have so long been a puzzle to anatomists are, he says, in reality nothing more than inter-mus- cular developments of this layer. In some species each of the lateral lines contains an axial vessel, though in very many others nothing of this kind is to be met with. A periodical ecdysis of the chitinous portion of the integument takes place in all Nematoids during the period of their growth. The author agrees with Dr. Schneider as to the nature of the transverse fibres attached to the median lines. They are contractile prolongations from the longitudinal muscles, and may be considered extrinsic muscles for the propulsion of the intestinal contents, since the intestine itself has no muscular tissue in its walls. 372 Mr. Bastian — Anatomy and Physiology ofNematoids. [June 15, Schneider's description of the nervous system in Ascaris megalocephala has been confirmed, and a similar arrangement has been recognized by the author in several other Nematoids. It exists as a nervous ring encircling the commencement of the oesophagus, in connection with many large ganglion-cells. The principal peripheral branches are given off from the anterior part of the ring, and proceed to the region of the mouth and cephalic papillae. Although well developed ocelli exist in many of the free marine species, no nerve-filaments have yet been detected in con- nexion with them. The organs of digestion are mostly simple, the principal variations being met with in the presence or absence of a pharyngeal cavity, and in the structure of the oesophagus. In some species its parietes are distinctly muscular, whilst in others, as in the Trichocephali and Trichosomata, they are as distinctly cellular. Those possessing a pharyngeal cavity sometimes have well-marked tooth-like processes developed from its walls ; but the author believes that the chitinous plates which are sometimes met with in posterior swellings of the oesophagus are not " gastric teeth," as they have been hitherto described, but rather valvular plates for ensuring greater perfection in the suctorial process by which these animals pass their food along this portion of the alimentary canal. The water- vascular system may be seen in many Nematoids in its most elementary condition, as a small tubular gland, with an excretory orifice in the mid-ventral region of the anterior part of the body. In other Nema- toids no trace of such a system exists ; whilst its most developed condition yet recognized in these animals may be seen in Ascaris osculata and A. spiculigera, where an intimate plexus of vessels, still in connexion with an anterior ventral pore, is met with in a peculiar development from the left lateral band. Intermediate conditions between these extreme forms may be traced in other species ; and from the obviously glandular nature of the tubular or pyriform organ met with so commonly in the free, and also in many of the parasitic species, he thinks considerable light is thrown upon the function of the " water- vascular " system. He says, " Here we have undoubtedly to deal with an excretory glandular apparatus. No one could for a moment regard these structures as at all analogous to vessels destined alternately to receive and discharge an external fluid medium. I believe that in the Trematoda and Teeniada also, where similar though often more developed systems exist, their function is in like manner one of a purely eliminatory kind ; and 1 therefore cannot but look upon the name of ' water-vascular ' apparatus as a singularly inappropriate appella- tion for this system of vessels." Other very peculiar transverse vessels exist in the deep integumental layer of Ascaris megalocephala and ^4. lumbricoides, mostly running in pairs from median line to median line, and, strangely enough, being about twice as numerous on the right as on the left side of the body. The author believes that in the Nematoids but little provision exists for 1865.] Mr. Bastian — Anatomy and Physiology of Nematoids. 373 the oxidating portion of the process of respiration, and thinks that this deficiency may be compensated by a greatly increased activity of glandular eliminating organs. Considering the conditions under whose influence so many of the parasitic forms pass their existence, we can easily imagine that the presence of any organs for effecting an oxidation of their tissues would not only be useless, but actually baneful. Glandular organs exist in the greatest abundance in all Nematoids, and many of these are excretory organs. In those species in which no modification of the ventral excretory apparatus is met with, the author has found a very large number of channels running through the chitinous portion of the integument, so as to bring its deep cellular layer in communication with the exterior. These pores are, he believes, complementary respiratory organs, and their development is always in an inverse proportion to that of the other excretory organs. Thus amongst the free Nematoids he has found them most numerous in Dorylaimus stagnalis and Leptosomatum figuratum — species in which the ventral excretory apparatus is entirely absent. The same arrangement is met with in the Trichocephali and Trichosomata, in which these integumental channels attain their maximum development. The gradually widening longitudinal band long known to exist in the Trichocephali is due to the presence of thousands of these channels in connexion with a glandular de- velopment of the deep integumental layer beneath. Many interesting facts are brought forward concerning the " tenacity of life " of some of the free Nematoids, and their power of recovery after pro- longed periods of desiccation. This has been long known as one of the characteristics of Tylenchus tritici*, but the author has found it common only to the species of four land and freshwater genera, — Tylenchus, Plectus, Aphelenchus, and Cephahbus. The remainder of the free Nematoids are remarkably frail, and incapable of recovering even after the shortest periods of desiccation. In the last section, on "The zoological position and affinities of the Nematoids," the author enters fully into what he believes to be the points of resemblance between these animals and the Echinoderms. The strongest evidence is, he thinks, to be found in the fact of the very close resemblance between the nervous systems of these animals, differing notably as it does at the same time from what we find in the Scolecida or Annelida. Then the integumental pores which he has now discovered in so many Nematoids can, he thinks, be paralleled only by the ambulacral and other pores met with in the Echinoderms. Great similarities in the distribution of these pores may also be observed in the two groups. The Nematoids present no trace of segmentation or lateral appendages to their bodies, but traces of a radiate structure do exist. Their various parts and organs exhibit a quadrate mixed with a ternate type of development. He looks upon the order Nematoidea as as aberrant division of the class Echinodermata, which at the same time tends to connect this class in the most interesting * Vibrio tritici of older writers. VOL. XIV. 2 F 374 Dr. Fox on the Development of [June 15, manner with the Scolecida — since, although in the points above mentioned they display their affinities to the Echinoderms, still, as regards the struc- ture and different modifications of the ventral excretory apparatus, they agree more closely with the Trematoda or flukes. XV. " On the Development of Striated Muscular Fibre." By WILSON Fox, M.D., Professor of Pathological Anatomy in University College, London. Communicated by Dr. SHARPEY. Received June 15, 1865. (Abstract.) The discrepancies in the statements made by various observers on the structure, as illustrated by the history of the development, of striated mus- cular fibre, have induced the author to submit the question to a renewed and independent investigation. He has examined the process in the tad- pole, the chick, the sheep, and in man, and with results which correspond very closely in all these classes. The investigation is most easy in the tad- pole, as the early structures are of much larger size ; but observations are made with a comparatively greater precision when high magnifying powers are employed. The author has used 900 linear in his observations on the tadpole, 1250 or 1850 linear in his observations on the chick and mammalia. The earliest form in which muscular tissue appears in the tadpole is an oval body containing one or more nuclei, and densely filled with pigmentary matter. This body has a well-defined outline, which in- duces the author to regard it as a cell, though he has not succeeded iu isolating any distinct membrane. Such bodies then increase in length with or without multiplication of their nuclei, and after a short period a portion of their structure loses in great part its pigment and exhibits a striation sometimes transverse, sometimes longitudinal, or occasionally both conjointly ; but there is no distinct line of demarcation at this stage between the striated and non- striated portion of the cell-contents, — showing that the change takes place within the contents of the cell. As the pigment gradually diminishes in the non-striated portion of the cell-contents, a membrane can in some cases be very distinctly observed limiting the whole structure, while in others it can only be seen around the non-striated portion, and in the former case the presence of a striated structure within this membrane is very distinct. The nuclei are always found situated in the granular non-striated portion of the contents of the cell. The cell may elongate to a very long fibre, to which only a single nucleus may be attached, or in the process of elongation a great increase in the number of nuclei may take place. In all cases the nucleus and fibre are enclosed by a membrane, which the author regards as an extension of the original membrane enclosing the cell in its earlier stages. The thickness of the striated portion appears to be in direct proportion to the number of nuclei enclosed within the membrane. With the advance of development the space occupied within the mem- 1865.] Striated Muscular Fibre. 375 brane by the granular non-striated as compared with the striated portion of the fibre diminishes, so that the latter almost entirely fills the mem- brane, the nuclei lying within the membrane but external to the striated portion, and surrounded by a small amount of the granular matter of the original cell-contents. The differentiation of the muscular fibre of the chick commences in the dorsal region, according to the author's observations, after about forty- eight hours of incubation. Here the first appearance is of nucleated oval bodies with well-defined outlines, but much smaller than in the tadpole, which the author regards as cells, though he has been unable to isolate a membrane. These rapidly elongate into fusiform bodies, in which some- times a faint striation becomes apparent. Shortly after the commencement of the third day long fibres appear, apparently from the elongation of the former, which are striated both longitudinally and transversely, and upon them is situated a nucleus, around which is some granular matter (the remains of the original cell-contents), the whole being enclosed by a membrane. From the fourth to the fifth day a great multiplication of the nuclei follows within the membrane, and in proportion to this multiplication does the diameter of the fibre, and also of the striated portion, increase. The author has observed a similar process in the growing extremities of the sheep and of man, and concludes that the growth of muscular fibre commences in the cells of the embryo by the elongation of the cells and multiplication of their nuclei, attended by a simultaneous fibrillation and striation of their contents. He regards the sarcolemma as resulting from the extension of the wall of the parent cell, but thinks that the adult muscular fibre should not be regarded so much in the light of a single many-nucleated cell, as the result of the fusion of many cells in the act of formation, the separation of which, after the division of their nuclei, has been prevented by the early fibrillation of their contents, — a view which ap- proximates somewhat to that held by Schwann, and which is also a mo- dification of the opinion expressed by Kolliker and Remak. The development of the muscular fibre of the heart in the chick com- mences, according to the author, after forty-eight hours of incubation, by the appearance of stellate cells, which anastomose with one another in all directions. The processes which these give off increase in thickness, and nuclei appear upon them, probably by multiplication of the nuclei of the original cells. Fibrillation and transverse striation of these processes ap- pear from the third to the fourth day. The structure becomes so complex after this period, that the author has been unable to follow the development further. He has not been able to find any membrane resembling the sar- colernma upon these processes from the stellate cells, though with a power of 1250 linear they may often be seen to have a double outline. He thinks the presence of a sarcolemma may be inferred from the fact that the position of the nuclei in relation to the striated portion is the same as 2 F2 376 Dr. Carpenter on the Structure, Physiology, [June 15, in other striated muscle, and that its excessive tenuity is probably the cause of its escaping observation. XVI. "Researches on the Structure, Physiology, and Development of Antedon (Comatula, Lamk.) rosaceus.'' By Dr. W. B. CAR- PENTER, F.R.S. Received June 15, 1865. (Abstract). The author, after adverting to the special interest attaching to the study of this typical form, as the only one readily accessible for the elucidation of the life-history of the CRINOIDEA, states it to be his object to give as com- plete an account as his prolonged study of it enables him to offer, of its minute structure, living actions, and developmental history, taking up the last at the point to which it has been brought in the memoir of Prof. Wyville Thomson. He prefaces his memoir with an historical summary of the progress of our knowledge of the distinctive peculiarities of this genus, and of its relation to the Crinoidea; and he shows that the first recognition of this relation- ship was most distinctly made by Llhuyd, at the beginning of the last century, though that recognition has been passed without notice by most subsequent writers, and is altogether ignored by MM. de Koninck and le Hon in their recent history. The author then proceeds to describe the external characters of Antedon rosaceus ; and shows, from its habits as observed in a vivarium, that al- though possessed of locomotive power, it makes so little use of this under ordinary circumstances, that its life in the adult condition, no less than in its earlier stage, is essentially that of a pedunculate Crinoid. He then gives a minute description of the several pieces of the skeleton — the accounts of these previously given by J. S. Miller and Prof. Job. Miiller not being in sufficient detail to serve as standards of comparison to which the parts of fossil Crinoids may be referred. And he directs special attention to the curiously inflected rosette-like plate, previously unnoticed, which occupies the central space left within the annulus formed by the adhesion of the first radials. This plate is in special relation to the organ termed by Joh. Miiller the " heart," but certainly having no proper claim to that designation, being a quinquepartite cavity in the central axis, from the walls of which there pass out not vessels but solid cords of sarcode, into the rays and arms, and also into the dorsal cirri. The inflexions of the rosette-like plate serve for the support and protection of the large cords passing into the rays, each of which has a double origin, and a connexion with the adjacent radiating cords that reminds the anatomist of the " circle of Willis." The skeleton of the adult differs so widely in the forms and relations of its parts from that of the early Pentacrinoid larva described by Prof. Wyville Thomson, that the derivation of the former from the latter can only be understood by observation of all the intermediate stages. When 1865.] and Development of Antedon rosaceus. 377 the calcareous skeleton of the calyx first shows itself, it consists only of five oral plates arranged conformably upon five basal plates, as thus : — O O 0 O 0 B B B B B At a stage a little more advanced (which has been described by Prof. All- man, Trans. Roy. Soc. Ed. vol . xxiii. p. 24 1 ), the rudiments of the first radial* are found interposed between the orals and basals, alternating in position with both, as in the margin ; and between two of these first radials there appears a single small unsymmetrical O O O 0 O plate, which afterwards proves to be the anal. The a a a a a first radials undergo a rapid increase in size, and B B B B B soon become surmounted by second and third ra- dials, which project between the orals ; whilst the orals and basals, under- going no such increase, are relatively very much smaller ; the anal plate is still found on the line of the first radials. But from this time the radials form the principal A3 A3 A3 A3 A3 part of the calyx, which opens out widely in A* A2 A2 A2 A* conformity with the increase of space required O O O O O for the digestive apparatus, the intestinal canal A' A'f^A1 A* ^ being now developed around what was originally B B B B B a simple stomach with one orifice. The highest joint of the stem also undergoes a remarkable increase in size, and begins to acquire the form of a basin with an inflected rim, constituting what is known in the adult as the centro-dorsal piece. When the calyx opens out, the five oral plates which originally formed a circlet around the mouth, retain that position, and detach themselves entirely from the divergent ra- dials, nothing but the soft perisomatic membrane filling up the space be- tween them. These oral plates never increase in size, and towards the end of the Pentacrinoid stage they begin to undergo absorption. I can still trace their basal portions in young specimens of the free Antedon ; but as the creature advances towards maturity they are altogether lost sight of. When the intestinal canal has been sufficiently developed to open on the surface of the oral disk, the anal plate is lifted out of the position it originally occupied, and is at last found on the anal funnel, far removed from the radials. This, like the oral plates, begins to undergo absorption towards the end of the crinoidal stage, and completely disappears in the early part of the life of the free Antedon. The radial plates increase not only in size but also in thickness ; and channels which are left on their in- ternal surface by vacuities in the calcareous network, are converted into canals by a further inward growth of this, which completely covers them in. It is through these canals that the cords of sarcode pass to the arms. The basal plates, like the oral, remain stationary in point of size, and pre- sent no change in appearance or position until after they have been com- pletely concealed externally by the centro-dorsal piece (the highest joint of 378 Mr. J. W. Hulke on the Chameleon's Retina. [June 15, the stem), which rapidly augments, both in absolute and in proportional size, when the development of the dorsal cirri is taking place from its convex surface. By the end of the Pentacrinoid stage, this plate has ex- tended itself so far over the base of the calyx as completely to conceal the basals ; and as the free Autedon advances towards maturity, it gradually extends itself over the first radials, which then become adherent to it and to each other. The basals then undergo a most curious metamorphosis, con- sisting in absorption in one part and extension in another, by which they finally become converted into five peculiarly shaped pieces, the ultimate union of which forms the single rosette-like plate, which has been already stated to lie within the annulus formed by the first radials of the adult Antedon. Hence the calyx finally comes to be thus composed : — R3 R3 R3 R3 R3 R2 R2 R2 R2 R2 y CENTRO-DORSAL. As the orals and the anal have entirely disappeared, no part of the pri- mordial calyx of the Pentacrinoid larva is traceable in it, until we separate the adherent pieces which form its base, and search out the minute and delicate rosette-like plate which is formed by the metamorphosis of the basals. The structure, physiology, and development of the digestive, circulatory, and respiratory apparatus, and of the nervous and muscular systems, will form the subject of a future memoir. XVII. " On the Chameleon's Retina ; a further contribution to the Minute Anatomy of the Retina of Amphibia and Reptiles." By J. W. HULKE, Esq. Communicated by WILLIAM BOWMAN, Esq. (Abstract.) The Chameleon's retina is peculiar in having a fovea and pecten, and in the nervous conducting fibres crossing the connective-tissue fibres in- stead of running parallel to them. The fovea was discovered by Knox in 1823, and minutely described by H. Miiller, who also discovered the singular arrangement of the two sets of fibres in 1862. It is a circular pit situated at the posterior pole of the eyeball. A dark brown dot, surrounded by a lighter areola, marks its centre. Here the bacillary layer, which contains cones only, is alone present. The cones of the fovea are long, slender cylinders placed vertically upon the choroid. From the centre of the fovea outwards, the cones become stouter, shorter, and more numerous towards the periphery of the retina, 1865.] Mr. J. Wood— Varieties in Human Myology. 379 where they are flask-shaped. The other layers reach their maximum de- velopment around the fovea at successively increasing distances from its centre. From the inner ends of the cones, fine fibres proceed obliquely from the outer to the inner surface of the retina in a radial direction from the centre of the fovea to the periphery of the retina. These fibres con- nect the cones with the cells of the outer granule-layer ; they next form a thick plexus at the inner surface of this layer, which I term the cone-fibre plexus ; then traverse the inner granule-layer, in which they connect them- selves with round and roundly oval cells, and are continued through the medium of the ganglion-cell-like cells of this layer into the granular layer, where they join the processes directed outwards from the cells of the ganglionic layer. Thus they constitute an anatomical path between the cones and optic nerve-fibres. These oblique nervous fibres are crossed by vertical fibres of modified connective tissue directed radially from the centre of the eyeball. Around the fovea the connective fibres traverse the cone-fibre plexus and the outer granule-layer in the form of stout vertical pillars corresponding to those which in the turtle I named the outer radial fibres ; while in the thinner periphery of the retina, the vertical, connective-tissue fibres are finer, and traverse all the layers between the inner and outer limiting mem- branes. The pecten lies excentrically at 1'" from the centre of the fovea. Its minute structure agrees with that of the Gecko's. The distribution of the optic nerve-fibres with respect to the fovea resembles that which obtains with reference to the yellow spot in the human eye. XVIII. " Additional Varieties in Human Myology." By JOHN WOOD, F.R.C.S., Demonstrator of Anatomy in King's College, London. Communicated by Dr. SHARPED Received June 9, 1865. In the past winter session thirty-six subjects have been dissected in the Anatomical Rooms at King's College. In them the author has directed especial attention to the combinations of muscular aberrations in the same individual, with a view to obtain data for ascertaining any relation that may subsist between such abnormalities in different parts of the body. In one subject, a muscular man about 5 feet 8 inches high, with promi- nent features, aquiline nose, somewhat high cheek-bones, well-pronounced chin, and good skull-development, an extensive departure from the ordinary type was observed in every part of the body, the abnormalities being more numerous than in any other subject previously noted. In the neck, on both sides, was a well-developed and powerful levator claviculce, in all respects like that first described and figured by the author in a paper read last year before the Royal Society. It was connected 380 Mr. J. Wood — Varieties in Human Myology. [June 15, above with the posterior tubercles of the second and third cervical vertebral transverse processes, arising with the fibres of the levator anguli scapulce. Passing downwards, forwards, and outwards, as a muscle about an inch wide, it was inserted into the outer third of the clavicle, behind the fibres of the trapezius muscle, and opposite the conoid tubercle of that bone. The fasciculus was muscular in nearly its whole extent (fig. 1 a). Fig. 1. Arising from the hinder border of the first rib with the sterno-thyroideus muscle, and passing over the common carotid artery to be inserted into the cervical fascia at the upper part of the neck, was a costo-fascialis cer- vicalis muscle, precisely similar to that described and figured in the paper before alluded to. 1865.] Mr. J. Wood — Varieties in Human Myology. 381 In the axilla, on both sides, the latissimus dorsi sent a muscular slip three-fourths of an inch wide, in front of the vessels and nerves, to be in- serted, with the upper sternal fibres of the pectoralis major, into the outer bicipital ridge of the humerus (fig. 1 c). A similar detached slip arose from the seventh rib, close below the pectoralis major, and was inserted separately into the bicipital ridge a little higher than the foregoing (fig. 1 b). From the outer border of the first rib, near the cartilage, arose a thin, fleshy, triangular muscle which, widening gradually, dropped fibres of in- sertion into the second, third, and fourth ribs, close outside the origin of the pectoralis minor. It was entirely distinct from the intercostals, and may be termed a supra- costal muscle. It existed on both sides, but was more marked on the left (fig. 1 rf). In the upper arm was a well-marked brachio-fascialis, exactly similar to that described in the last paper, arising with the upper fibres of the brachialis anticus, and inserted into the semilunar fascia of the elbow, intervening between the brachial artery and median nerve close above the bend of the elbow. In the right arm only was a large fusiform muscle, arising, by a thin lunated aponeurotic tendon, from the oblique line of the radius under the origin of the flexor sublimis, and inserted by a narrow spreading tendon into the deep surface of the anterior annular ligament close to the tra- pezium. Some of the fibres could be traced into the middle portion of the palmar fascia. This muscle was also found in another muscular male, associated, as in this case, with a remarkably developed extensor brevis digitorum manus. It seems to be a homologue of the tensor fascia plant aris given in the series of drawings accompanying the last paper. A strong and distinct palmaris longus and brevis were also present. There was increased differentiation of the flexor sublimis digitorum. The flexor pollicis longus gave a strong muscular slip to the indicial portion of the flexor profundus digitorum. The third lumbricalis was double, half going to the third and half to the fourth digit, and implanted in the usual manner into their opposed sides. This was also seen in another subject. There was an extensor proprius digiti medii from the lower end of the back of the ulna and interosseous ligament, distinct from the indicator muscle, and inserted into the dorsal expansion of the common extensor tendon, lying on its deep surface and sending lateral slips to the metacarpo- phalangeal ligaments. The extensor ossis metacarpi pollicis, on both sides, had three distinct tendons, one to join the abductor pollicis, another to the front of the tra- pezium, and the third, the largest, to the base of the metacarpal bone. This is a common arrangement. 382 Mr. J. Wood — Varieties in Human Myoloyy. [June 15, The left abductor pollicis was a double muscle, which is also commonly found. On the back of both hands was a good specimen of the muscle first described and figured by the author, in his last paper, as an extensor brevis digitorum manus. It was arranged in three slips, arising by a common aponeurosis from the magnum and unciform bones, the two outer inserted with the dorsal interossei muscles into the extensor aponeurosis at the base of the middle finger ; and the inner, into the same structure at the base of the ring-finger. This muscle was also found very well marked in another muscular male arm, associated with the fusiform deep palmaris just described. Fig. 2 is drawn from this specimen, and it will be seen that in it there is a still closer approach to the ar- Fig. 2. rangement of the extensor brevis digitorum pedis, inasmuch as the outermost slip is not inserted with the second dorsal interosseus into the middle finger, but with the first palmar interosseus into the ulnar side of the index or second digit and its extensor aponeurosis. This specimen has been preserved as a preparation for the Hunterian Museum of the Royal College of Surgeons, where it may be in- spected by those interested in the question. In the foot of the subject first mentioned, the tibialis anticus on both sides, sent forwards a tendi- nous slip, one-eighth of an inch wide, to be inserted with the tendon of the extensor proprius hallucis into the base of the first phalanx of the great toe. (This was also found in a female subject on both sides.) The peroneus brevis sent off a tendinous slip (peroneus quinti) to the ex- tensor aponeurosis of the little toe on both sides. The peroneus tertius, on both sides, had a very broad tendon, which was inserted into the base of the fourth as well as the fifth metatarsal bone. The same peroneal disposition (tertius and quinti) was also observed in another muscular male foot, with an additional peculiarity which caused it to be selected as the subject of fig. 3, where it is seen at a. In both these sub- jects an abductor ossis metatarsi minimi digiti was present on both sides. In 1865.] Mr. J. Wood— Varieties in Human Myology. 383 the subject of the figure, it was the largest specimen the author has met with since he first discovered the muscle as a frequent abnormality in the human foot. Fig. 3. In the second metatarsal space, both the bones forming its sides gave origin to both the plantar and dorsal interossei muscles, producing the appearance as if the dorsal interosseus proper were divided between the second and third digits. The arteries of the arm in this subject were generally irregular. There was an axillary origin of the radial, and the superficial arch supplied the index and pollex by the aid of a large superficial volar. We have thus in this remarkable subject a development of a true levator claviculee, such as is found in all kinds of apes, monkeys, and bats, and offsets from the pectoralis major and latissimus dorsi similar to the chon- dro- and dorso-epitrochlear found also in these animals and the mok'S and birds. We have further a brachio-fascialis or quasi third head of the biceps usually found in birds; a muscular connexion between the flexor pollicis 384 Mr. J. Wood — Varieties in Human Myology. [June 15, longus and flexor digitorum profundus, as found in the apes and monkeys ; with a curious addition of the nature of a tensor fasciae palmaris, forming a close homologue with the plantaris flexor found in many of the lower animals ; a double lumbricalis, as often seen in the apes j and a proper ex- tensor of the middle finger. There is a redundancy of the extensor ossis metacarpi pollicis and abductor pollicis, and an extensor brevis digitorum on the back of the hand. This last curious muscle the author has now traced in all stages of its segregation and posterior displacement from the fibres of the dorsal interossei, which indicate strongly the light in which we should view this muscle on the dorsum of the foot. (In the fore paw of the Sloth, Professor Huxley has shown the author a similar displacement and use of the dorsal interrossei as extensors of the digits, while the palmar, as in most of the lower animals, fulfilled the part offlexores breves as well as divaricators of the digits. This function in the Sloths is rendered neces- sary by the imperfect development and abnormal displacement of the tendons of the extensor lonaus.) Lastly, in the foot of this subject we have the tibialis anticus and peroneus brevis muscles sending forwards tendinous slips to their respective digits (first and fifth). A special abductor of the metatarsal bone of the fifth digit, such as Professor Huxley and Mr. Flower have shown to exist uniformly in the higher and lower apes, and a double origin of the first plantar interosseus muscle, complete the list of irregularities which render the above subject one of the most re- markable the author has ever dissected. In a thin female subject of low stature was found, on the right side only, the remarkable muscle given in fig. 4. It consisted of a roundish fusiform slip (o) arising tendinous from the first cartilage below the subclavius close to the manubrium sterni, passing across the subclavian vessels and nerves quite distinct from the last-named muscle, and inserted into the upper border of the scapula and suprascapular ligament, where it was connected, to some extent, with the origin of the omo-hyoideus (c). From this point of insertion another slip of muscular fibres passed forwards, upwards, and outwards, to be inserted, with the subclavius, into the outer third of the clavicle (b). This muscle seems to be the same as that given in the author's first series under the name of a double subclavius, with the addition of a con- necting slip to the clavicle. It seems to the author to represent pretty closely the sterno-scapular muscle, while contributing to support the thorax in the pachyderms and ruminants, in which animals it is continued as far as the manubrium. In the same subject was a slip, on the left side only, arising from the eighth rib, with the digitation of the serratus magnus, and inserted into the short head of the biceps close to the coracoid process. A rather larger muscle like this was described and figured in the first series, under the name of a chondro-coracoid muscle. There was a third head of the biceps on the left side, arising with the brachialis anticus, and on both sides 1865.J Mr. J. Wood — Varieties in Human Myology. 385 a scapular head of the latissimus dor si, and a tendinous slip from this muscle to the long head of the triceps. Fig. 4. In the left arm of this subject, was found, for the fourth time, the curious muscle first described in the author's last paper as the extensor carpi radialis accessorius, arising by a broad fleshy head from the external condyloid ridge of the humerus, below and distinct from the extensor carpi radialis 386 Mr. J. Wood — Varieties in Human Myology. [June 15, longior, and inserted by a long tendon into the base of the metacarpal of the pollex, below and distinct from the extensor ossis metacarpi pollicis. In this instance no slip was given to the abductor, as is sometimes the case. The author had the satisfaction of showing this specimen to Pro- fessor Sharpey, with the levator claviculee before described. Professors Ellis and Huxley, and Messrs. Flower and Pettigrew of the Royal College of Surgeons, also inspected it. It was not present on the right side, but here a muscular connexion existed between the supinator longus and ex- tensor carpi radialis longior. There was no palmaris longus on the left side, and only a small one on the right. On the left side also the fourth lumbricalis was absent. In the body of a fine young Negro, which was very carefully dissected and observed, few departures from the ordinary muscular arrangement were observed, and these were present only in the upper extremity. In the left arm was a complex arrangement of the flexor sublimis digitorum. Two large muscular slips from the coronoid origin of this muscle passed to the tendons of the deeper muscles. The inner and more superficial ter- minated in two long tendons, which passed separately under the anterior annular ligament, and became blended in the middle of the palm with those of the flexor profundus going to the fourth and fifth fingers. The outer slip also divided (a little higher up) into two tendons. One of these joined, in the middle of the forearm, that of the flexor pollicis longus; and the other, after receiving a muscular head from the radius below the last-named muscle, became connected in the palm with the perforating tendon of the index, giving part origin to the first lumbricalis. Here were three ad- ditional tendons intermediate between the flexor sublimis and profundus, passing separately under the annular ligament. Additional tendons have been before met with in this position in Europeans, but the author does not remember to have met with them to the extent seen in this Negro. In the same arm, the third lumbricalis joined the ulnar side of the middle finger instead of the radial side of the ring-finger, which had no lumbricalis. The interossei muscles were regular, that to the thumb (the first palmar of Henle) was also present. All the palmares muscles were well developed, as well as the plantares and the peroneus tertius. The latter was con- nected at its origin (as is commonly found) more intimately with the exten- sor tendons of the fourth and fifth toes, than these were with those of the second and third. The arteria comes nervi mediant was very large, forming the greater part of the superficial palmar arch, and supplying the thumb and index. In a well-formed tall adult Lascar, with a good cranial development, features of an elevated type, and of a deep olive colour, the most careful observation detected no further irregularity than an extensor proprius of the middle finger on both sides, arising partly in common with the indi- cator, and inserted into the common extensor aponeurosis. There was also an increased differentiation of t\\e flexor sublimis diyitorum. 1865.] Mr. J. Wood— Varieties in Human Myology. 387 In two muscular male subjects were found a well-marked sternalis brutorum, very similar to that figured in the last series, and in both (as in that case) on the right side only. In another male it was found on the left side only ; and in a fourth, slips of tendon, intermingled with muscular fibre, were found on both sides, passing from the sternal tendon of the sterno-mastoideus down to the cartilages of the ribs as low as the sixth, and evidently of the nature of a sternalis muscle. Two of these subjects were affected with further abnormalities, confined to the arms. In the right arm of one was found the tensor fascia palmaris before described, and associated with the extensor brevis digitorum manus (given in fig. 2). The latter was present in both hands. The palmaris longus on the left side was much stronger than that on the right. In the right arm also was a muscular slip connecting the flexor profundus with the flexor longus pollicis, a double indicator muscle, and no less than three ex- tensor tendons to the little finger. In the subject in which the sternalis brutorum existed on the left side only, were found, in both arms, slips connecting the flexor sublimis with the flexor longus pollicis, and a distinct muscle, arising from the radius inside the last muscle, and be- coming connected, by means of a long and strong tendon, with the perfora- ting or deep tendon of the index just below the annular ligament, pre- cisely similar to one given in the last series. On the dorsum of both hands were found three well-marked and distinct muscular slips, forming an extensor brevis digitorum, arising in common as high as the posterior annular ligament. Small slips representing these, and passing to the middle and ring-fingers only, have been found in no less than six other subjects during last session. In another male left arm were found combined the following abnor- malities, viz. three heads to the biceps, a double palmaris longus, and a double tendon to the extensor minimi digiti. Right arm normal. In two subjects were seen, in the legs, good samples of the extensor primi internodii hallucis, distinct muscles, with a strong tendon, as de- scribed and figured in the last series. In five subjects were found, on both legs, tendinous slips representing the peroneus quinti. In that from which fig. 3 was taken (a very tall and muscular man), it will be seen that the digital slip passes in a curious way through a division of a large tendon of the peroneus tertius, at its insertion into the bases of the fourth and fifth metatarsals. It is associated also with an abductor ossis metatarsi minimi digiti. In connexion with these more common irregularities of the peroueal tendons, the author would call attention to that given in fig. 5 from a left female foot, in which the tendon of the peroneus longus (a), as it turns over the cuboid bone, gives distinct and sole origin to the flexor brevis minimi digiti (b), and to the outermost plantar interosseus of the same digit (c). Of other detached muscular abnormalities observed during the session, 388 Mr. J. Wood — Varieties in Human Myology. [June 15, Fig. 5. the more remarkable may now be briefly de- scribed. In a female was found, on both sides, an in- creased development of a common irregularity, viz. a broad muscular slip from the tendon of the latissimus dorsi, passing across the axillary vessels and nerves to be inserted with the deeper or sternal fibres of the pectoralis major. This slip was separated from the rest of the latissimus by a well-marked tendinous intersection, and was connected with the ninth rib. In a male subject, which presented an abnormal subclavian slip of muscle closely resembling that in fig. 4, were found upon the larynx two small but curious muscular slips arising from the lower border of the thyroid cartilage on the left side, between the crico-thyroid and thyro-hyoid muscles, and pass- ing obliquely across the median line, in front of the thyroid isthmus, to be inserted into the front of the fifth, ring of the trachea, near to and parallel with each other. They seemed to be prolonga- tions of the superficial fibres of the crico-thyroi- deus, with the tendency to cross the median line more commonly shown by the hyoid and laryngeal muscles than else- where. In a male pharynx, the middle constrictor showed an irregularity. A few of the upper fibres, on both sides, arose from the vaginal process of the temporal bone, and, curving inwards and upwards, were inserted with the rest of the upper fibres of the constrictor into the pharyngeal ridge and median raphe. This[arrangement is somewhat different from that of the salpinyo-pharyngeus described by Cruveilhier and not unfrequently found in this situation. In both arms of a muscular male was found a small slip of tendon giving off a fourth head to the biceps, and springing from the lesser tuberosity of the humerus at the insertion of the capsule and tendon of the sub- scapularis. This is a bicipital head of the same character as the fourth head described by Meckel as arising sometimes from the greater tubero- sity at the edge of the bicipital groove. The third head in the present case arose in the usual situation, from the upper fibres of the brachialis anticus. In a feebly developed male left arm was found a curious offset from the flexor pollicis longus. On its inner side, arising partly in common with this muscle, was a penniform muscle of good size, ending in a long and strong tendon which, after passing under the annular ligament, became continuous with the outer of the two heads of a double first lumbricalis 1865.] Mr. J. Wood — Varieties in Human My ology. 389 muscle. The other head was derived in the usual penniform way from the indicial tendon of the perforans. The whole muscle was larger than common, and was inserted in the usual way. The same hand presented also a double insertion of the third lumbricalis, which was divided between the inner side of the medius and the radial side of the ring-finger, and inserted in the usual way. The middle finger is thus provided with a lumbricalis on each side. An exactly similar ar- rangement to this was found in another subject, a female, on both sides. In a muscular male, the extensores radiales of the left arm exchanged tendinous slips of considerable size. That from the longior was highest, and joined the brevior just below the place where the latter gave off its return slip to join the tendon of the longior at its insertion into the base of the second metacarpal. Mr. Langrnore, a student of University Col- lege, has lately written to the author to say that he has seen in a subject there dissected, a muscle arising with the extensor carpi radialis longior, the tendon of which, passing under that of the brevior, was inserted to its ulnar side into the base of the middle metacarpal. These irregularities are interesting in their bearing upon the occasional occurrence of the extensor carpi raaialis accessorius before described. This muscle, how- ever, is distinguished from all these by its insertion into the metacarpal of the pollex, and its frequent connexion with the abductor in the manner of the tendon of the extensor ossis metacarpi. In many feet of both sexes, examined during the session, were found sesamoid bones developed in the tendon of the tibialis anticus, and playing over a bursa on the internal cuneiform cone. In one, a male, a strong distinct slip of tendon passed from it to join and strengthen the inner division of the plantar fascia, being ultimately attached to the base of the great toe. In many of the same feet, and in others, a sesamoid bone was likewise found in the tendon of the tibialis posticus, placed to the inner side of, and playing over, the scaphoid bone. Its relation to the occurrence of an additional tarsal bone in this situation in the hinder limbs of the Arma- dilloes and other Edentata is suggestive. The special muscle found at- tached to it in these animals is produced apparently by a differentiation of fibres of the tibialis posticus, similar to that which frequently occurs in the tibialis anticus in the human subject, as shown in the author's last paper read before the Society. In a small male foot (right) was found a slip of muscle revealing a transitional formation towards that universal in the apes, and sometimes seen complete in the human subject. A small slip of muscle from the flexor brevis digitorum (fig. 6 6) is joined by a similar one, arising by a tendinous origin from the outer part of the tendon of the flexor longus (a). The two, after joining, result in a tendon, which instead of forming a regular perforatus for the little toe, becomes blended with that of the long or perforating flexor at the first phalanx, giving off slips VOL. XIV. 2 G 390 Mr. J. Wood — Varieties in Human Myology. [June 15, only to the middle and ungual phalanges. On the other foot no ab- normal muscle, but a similar blending of the tendons of the little toe was found. Attention having been drawn by Mr. Huxley to the importance of as- certaining the arrangement of the interossei muscles in the hand and foot, and especially the usual or most frequent manner of insertion in the toes in the human subject, the author has carefully examined these muscles in a considerable number of subjects. It was found that in the hand, although the origin of these muscles is usually such as de- scribed in anatomical works, viz. of the dorsal by a double penniform arrangement from the adjacent metacarpals, and of the palmar by a single penniform origin from the metacarpal of its own digit, yet iu several cases the so-called first palmar interosseus, viz. that of the index, had a bi- penniform origin from both second and third metacarpals, exactly as that on the corresponding side of the same digit in the foot. This abnor- mality is sketched in fig. 7 «. The dorsal interosseus of the same space covers it by its double penniform origin (one portion of which is repre- sented divided in the sketch). Fig. 6. Fig. 7. Both the muscles are perforated by the arterial branch of communication from the dorsum to the palm. In this hand is also well seen the palmar 1865.J Mr. J. Wood — Varieties in Human Myology. 391 interosseus of the thumb (6) exposed by the division of the abductor indicis, and lying upon the flexor brevis, with the deep fibres of which it is usually confounded. The insertions of these muscles are invariably (as usually described, and as seen in the sketch) divided between the base of the phalanx (where it is blended with the capsular investment of the joint derived from the extensor aponeurosis) and the sides of the extensor tendon, passing with the fibres from the lumbricalis, partly to the middle, and chiefly to the ungual phalanx. In the foot, the same occasional reference to the type occurring in the hand is found, in the origin of the first plantar interosseus. This muscle is sometimes a double penniform, arising from the adjacent second and third metatarsals on the plantar aspect of the second dorsal, and, like it, per- forated by the communicating artery. In both the hand and foot where these irregularities are found, the respective digits to which the muscles are attached seem somewhat larger in proportion than is usual, the size and extent of attachment of the muscles appearing to be determined by the size and uses of the corresponding digit. The foregoing abnor- malities of the interossei reflect some light upon the differences in the normal arrangement in the upper and lower extremities, which have often perplexed anatomists. The terms dorsal and plantar or palmar, referring to position only, and not to the action of these muscles, have apparently somewhat obscured the homologies of the separate muscles. In the hand, the middle digit being the most bulky, has a double or dorsal interosseous muscle for each of its divaricators. Its divaricator to the pollex excludes from the third metacarpal the divaricator from the pollex of the second digit, and obtains origin for itself from the dorsal part of the second metacarpal, so becoming a dorsal muscle. The transverse convexity of the back of the hand gives a dorsal prominence to the middle metacarpal and its digit over the rest. This explains the circumstance of this muscle assuming a dorsal position over the palmar interosseous of the index. In the foot, the first and second metatarsals and their digits attain a greater proportionate size and dorsal prominence, to fulfil their chief func- tion of sustaining and propelling the body. Here we find the divaricator to the pollex of the second digit (the first palmar interosseous of the hand) becoming developed into a double penniform muscle, with a dorsal position, excluding the divaricator to the pollex of the third digit (the second dorsal of the hand) from attachment to the second metatarsal, and itself acquiring an origin from the third metatarsal. An occasional recurrence of one to the type of the other might have been expected under peculiar conditions of development. Mr. Huxley informs the author that he has found, almost invariably, that the inter- osseous muscles in the foot are inserted entirely into the bases of the pha- langes, and are not, as in the hand, prolonged by a tendinous expansion in 2 o 2 392 Prof. N. S. Maskelyne on New Cornish Minerals [1865. common with the lumbricalef, into the extensor aponeurosis, and so to the middle and extreme phalanges. He looks upon this as one characteristic distinction between the hand and foot. In the arrangement which the author believes to be almost general in respect to the insertion of the interossei in the foot, and which supports essentially Mr. Huxley's view, it will be found that the bulk of each tendon is implanted into the base of the first phalanx, blendingwith the lateral ligaments of the metatarso-phalangeal joint, while only a few of the dorsal fibres are sent upwards and forwards, to meet and blend with the slips sent down to the sides of the joint from the extensor aponeurosis. These are not, however, so distinct and powerful as we find them in the hand, and, in their thin and scattered appearance, differ entirely from the insertion of the lumbricales tendons into the more forward part of the same extensor aponeurosis. " On New Cornish Minerals of the Brochantite Group." By Professor N. STORY MASKELYNE, M.A., Keeper of the Mineral Department, British Museum. Communicated by A. M. STORY MASKELYNE, M.A. Received February 13, 1865*. In March last my attention was drawn to a very small specimen of Killas, with some minute blue crystals on it, associated with a few equally small green crystals. The latter I proceeded to investigate with the goniometer. They proved to have almost identical angles with Atacamite, and, presuming them to be crystals of that mineral, I neglected them in order to measure the angles of the blue crystals. These proved also to belong to the pris- matic system, and evidently were a new mineral. The specimen had come to the Museum from Mr. Tailing, of Lostwithiel, a dealer from whom the National Collection has received a very large proportion of its finest Cornish minerals, and whose attention had been called to this specimen by the novelty of its appearance. Mr. Tailing no sooner was apprised of the in- terest attached to his little fragment of Killas, than he set energetically ' about tracing it to its locality. After a short time he succeeded in finding this locality ; and though he has not yet divulged it, he soon forwarded other specimens to me at the British Museum. He has since found fine masses of the minerals, which are described in this memoir, and they are now in the collection under my charge. The Killas which usually carries these minerals is of a very friable texture, often occurring as a breccia cemented by the minerals themselves, and at other times coated by them as incrustations. Sometimes, however, they are found on it as minute crystals scattered over, and in direct contact with, the rock, or in a succession of layers de- posited on it. In the latter mode of occurrence, the stone, whether Killas * Read February 23, 1865: see Abstract, p. 86. 1865.] of the Brochantite Group. or, as occasionally, a quartzose vein-stone, usually presents on its surface a very thin glaze of a greyish-white colour, and endowed with a remarkable metallic lustre. On this a thin layer, sometimes but -^th of an inch in thick- ness, of the blue crystals is met with, and on that a thicker agglutinated mass of the same mineral of rather a paler blue colour. Sometimes this paler variety exhibits a very fine sky-blue colour, and assumes the form of folia- tions with the appearance of small and extremely thin crystals, which are, in fact, an aggregate of crystals generally twinned, and in the form of laminae. Above the whole is occasionally seen a coating, varying in thickness from an eighth to half an inch, of a faintly bluish- or greenish-white mineral with a fibrous, and sometimes a slightly foliated, structure. The place of the blue mineral is often taken by one of a fine green colour, varying from a dark emerald to verdigris-green, and often crystalline. Oc- casionally also crystals of Brochantite may be seen, sometimes in clusters, and occasionally also mixed with this green mineral. I. On Langite. The first of these minerals that I propose to describe is that which occurs in crystals and crystalline masses, whether of the deeper or lighter lines of blue. I propose to call it Langite, in honour of my valued friend and late colleague Dr. Viktor von Lang, now Professor of Physics at Gratz. Langite crystallizes in very minute generally dark and somewhat greenish blue crystals belonging to the prismatic system, the ratios of the parameters being a : b : c= 1 : O'o347 : 0'6346. The forms observed are (1 0 0), (0 0 1), (1 1 0), (2 0 1), and (010). The inclinations found between normals to thin planes being 10000 1=90 11011 0=56 16 001 201 = 51 46 11020 1 = 68 8 10011 0=61 46 61° 52' calc. 10001 0 = 90 The crystals are for the most part twinned similarly to those not unfre- quent in cerussite : twin axes (1 10). T 1 0 (1 1 0) I 1 0=112 32 1^00 (1 10) 100=123 44 1 1 0 (1 1 0) 1 "I 0= 67 28 394 Prof. N. S. Maskelyne on New Cornish Minerals [1865. Cleavage parallel to 0 0 I distinct ; parallel to 1 0 0 nearly equally so. The plane 0 0 1 is brilliant ; 1 0 0 rather less so, as is the rarer plane 010; the plane 1 1 0 sometimes exhibits hollows, the sides of which are parallel to the cleavages. The specific gravity of the mineral is 3'48 to 3*50. Its hardness less than 3. On looking through a section of one of these microscopic crystals of Langite, ground parallel to the plane [ 0 0 1] in the polarizing microscope, the plane of the optic axes is seen to be parallel to 100; but though coloured rings are visible, the axes lie beyond the field, and the double refraction is weak. Probably, however, the first mean line is the normal to 0 0 1, and it is negative. The symbol for its optical orien- tation would be b c CT The crystals present dichroism : — 1st. As seen through 0 0 1 (along axis b c) : C (plane of polarization || to 1 0 0) greenish blue. b (plane of polarization [| to 0 1 0) blue. 2nd. As seen through 100 (along axis a) : C (plane of polarization [| to 0 0 I) darker bluish green. 0. (plane of polarization || to 0 1 0) lighter bluish green. It is a fact worthy of remark that Langite is geometrically isomorphous with Leadhillite. Langite is insoluble in water, but readily soluble in acids and ammonia. When submitted to the action of heat, it loses its blue colour, turning at first bright green. As the heat is increased, it passes gradually through various darker hues of this colour, till it becomes of a dull olive-green, and ultimately black. Water is given off the whole of the time, which in the later stages of the change has an acid reaction. Before the blowpipe, it gives off water and acid fumes, colours the flame green, and becomes reduced to metallic copper with carbonate of soda on charcoal. The chemical composition of Langite is represented by the empirical formula, 4Cu"05H'2OS04. which may be written as The copper was determined in one case (i.) by precipitation on the interior of a platinum crucible, by means of a cell of a Grove's battery, a method that seems, however, to give the value of the metal in excess ; in other cases (ii., iii., and iv.) by means of the volumetric method, wherein the iodine set free on precipitation of copper by an iodide is determined by means of starch and hyposulphite of soda. The sulphuric acid was de- termined in the usual way. The water in two cases (i. and ii.), by mixing the powdered and dried mineral with previously ignited carbonate of barium and heating the mixture in a combustion-tube in a current of dry 1865.] of the Brochantite Group. 395 air, the liberated water being retained by sulphuric acid iu pumice in a bulbed TJ-tube. In the other cases the mineral was heated with oxide of lead, and the water estimated by the loss. From the slight differences in the numbers given by the sulphuric- acid determinations in these minerals, and from the difficulty of determining the values of traces of iron, lime, and impurities as disturbing elements in the calculation of the analysis, the water-determinations are especially impor- tant. The following are the numbers the analyses have yielded me — 1st, crystals of Langite, carefully selected ; and 2nd, of the much paler blue incrustation or aggregation of crystalline Langite, generally showing the plane 0 0 1 largely developed on the surfaces of the incrustation : — Copper-Determination. I. Picked crystals. Grammes. Per cent. i. 0-2024 gave 0'1074 copper, corresponding to 53'06 ii. 0-2185 took 18'18 cub. centims. of standard solution of hypo- sulphite of soda, corresponding to* .... 52-26 iii. 01866 „ 15'2 „ „ „ „ 52-10 II. Pale Blue Langite. iii. 0-4295 „ 35-8 ' „ „ „ „ 52-80 Average =52'55 Sulphuric Acid-Determination. I. Picked crystals. 0-2746 gave 0-1297 Ba SO4, corresponding to -04457 SO3 . . =16-20 1-6687 „ 0-80475 Ba SO4, corresponding to -27587 SO3 . . =16'23 0-288 „ 0-1375 Ba SO4, corresponding to -0470085 SO3 . . =16'35 II. Pale Blue Langite. 0-1701 „ 0-0826 BaSO4, corresponding to -028387 SO3 . . =16-61 0-4295 „ 0-2094 Ba S04, corresponding to '07196 SO3 . . = 16-75 Average =16-42 Water-Determination. I. Picked crystals. i. 0-3622 lost . . . 0-0649 Water, corresponding to .... 17'93 [ii. 0-4737 „ ... 0-0915 „ , 19-31] f iii. 0-7210 with oxide of lead 0'1326 . „ „ .... 18'39 II. Pale Blue Langite iv. 0-2258 0-0423 . .... 18-73 Omitting the 2nd, the average=18'3l7 There are traces of lime and iron ; of the latter I found in one experi- ment 0'03 per cent. * Two preliminary experiments with the standard solution on pure crystallized sul- phate of copper and one on pure copper gave 99-66 per cent. ] 99-965 „ \ of the copper required by calculation. 99-92 „ J t A little acid came over in this experiment. 396 Prof. N. S. Maskelyns on New Cornish Minerals [1865. The formula 3 Cu" H'2O2 + Cu" S04 + 2H'2 O requires the following numbers * : — Calculated Average percentage. found. 4 equivalents of copper 12672 = 52-00 52-55 4 „ oxygen 32 = 13-13 (calc. 13-268) 1 „ sulphuric anhydride 40 = 16-41 16'42 5 water . . 45 = 18-46 18'317 243-72 100-00 100-55 In order to determine the proportions of water on which the blue colour of the Langite depended, and, if possible, to obtain some insight into the nature, or, at least, the number, of the different degrees of the hydration, 1-6987 gramme of the crystals, after having been previously powdered and dried in dry blotting-paper, were heated in an air bath. The result was a loss :— At 0 100 C. of -02625=1-54 per cent, water Between 100 and 120 C. of -03825=2-25 120 and 140 C. of -03900=2*30 (begins to turn green). 140 and 180 C. of -0620 =3-650 180 and 190 C. of -0692 =4-216 190 and 220 C. of '096 =5'651 „ (turns dark olive). 250 C. of -1352 =7-959 255 C. of -1402 =8-254 260 C. of -1472 =8-616 290 C. decomposition. 2 equivs. ofHO = 7'384. The passage, then, of Langite, under the influence of heat, into a substance with the formula 3 Cu" H'2O2 +Cu" SO4 + H'2O would take place at a temperature of about 180° C. ; and it would further pass into a substance with the formula of Brochantite, 3 Cu"H'202 + Cu" SO4 at a temperature of about 23.0° or 240° C. A transition, however, so effected would probably be incompatible with a new crystalline structure in the mineral resulting from it, which would be, in fact, a pseudomorph . The high temperature requisite for the expulsion of the last three equi- valents of water, which cannot be performed without decomposition, would seem to give colour to the belief that this water is in more intimate associa- tion with the oxide, and forms with it a hydrate. It is a fact worthy of remark that I have found one old specimen in which Langite is associated with Connellite. I convinced myself that the mineral was Langite by removing a crystal and measuring it. It gave the * I have adopted in this paper the doubled equivalents of all the elements involved in my formula*, except hydrogen. 1865.] of the Brochantite Group. 397 angle of the prism 1 1 0, fl 0 = 56°34', TOO (I 1 0) 1 C 0 = 124° 10' (calculation requires 123° 44'). II. Waringtonite. The mineral to -which I would next invite attention is one with a colour varying from emerald to verdigris-green that occurs sometimes mixed with Langite, but more often forming with it a continuous coating on the Killas or vein-stone, one part of this coating being in such cases Langite, and another part of it consisting of the mineral in question. At first I was in doubt whether this green body was not the result of the action of heat on Langite— in fact a pseudomorph after that mineral. Subsequently, however, Mr. Tailing sent me some unmistakeably crys- talline specimens, and as at that time I had already made its analysis, there could no longer be any doubt that it was a new mineral. I propose to call it " Waringtonite " in honour of my friend Mr. Waring- ton Smyth, Inspector of Mines to the Crown Lands, and to the Duchy of Cornwall, &c. The crystallography of Waringtonite presents a difficult problem, for the reason that it carries only one very distinct plane. The prevalent form of the crystals, which are almost microscopic, is that of a double curved wedge (or, to use a familiar illustration, like a stonemason's double- edged hammer), the flat summit being formed by this distinct but narrow plane. That plane is characterized by great brilliancy, is bounded by curved outlines, and though often fissured near its extremities by the accu- mulation of two or more parallel crystals in optical contact at their centres, is otherwise without striation. If we call this plane, by its analogy to the brilliant and unstriated plain in Langite, 001, and refer a very minute plane occasionally seen on the acute edges of the wedge to the form I 0 0, we find the planes 0 1 0, 0 1 0, and those in the zone [0 1 0, 0 0 1] repre- sented by rounded surfaces, from which it is impossible to obtain any accu- rate measurements ; and the prism planes in the zone [1 0 0, 0 1 0] are likewise much curved. There would seem to be two prisms in that zone, one of which forms a normal angle approximately determined as 1 1 0, T 1 0 = 28° 30' very nearly. It is difficult to say whether \Varingtonite is prismatic or oblique. The plane 0 0 1 forms an angle of 90° with those in the zone [0 10, 100]; and the principal planes indicated by the planes of polarization, as seen on looking down the normal to 0 1 0, are parallel to 1 0 0 and 001; but it is very difficult to speak with certainty as to the exact directions of the planes of polarization as seen when looking through the plane 001, and as to the direction of a plane of polarization really bisecting the acute angles of the wedge. The crystals often occur in interpenetrating forms, with the appearance of being twins. The angles, however, between corresponding planes in the two indivi- duals are not sufficiently uniform for the establishment of a twin plane. 398 Prof. N. S. Maskelyne on New Cornish Minerals [1865. The analysis of Waringtonite yields numbers that conduct us to the formula 3 Cu" H2' O2 + Cu" S94 + H'2 O, as the results which follow suffice to prove. Copper-Determination. grammes. per cent i. -1925 yielded (by precipitation) '1054 eopper=54'75 ii. '334 took 29'20 c.c. of standard solution of hyposulphite sodium . = 54*44 iii. -320 ,, 27-40 „ „ . =54'252 Average =54-48 Sulphuric Acid-Determination. i. -2104 yielded '1001 grm. Ba SO4 =16'22 SO3 ii. -4201 „ -2060 „ =16-825 iii. -3200 -16017 =17'16 Average =16-73 SO3 Water-Determination (3) -4041 amorphous substance yielded when ignited with carbonate of barium -0607 = 14-18 2 '4891 picked crystalline Waringtonite -0777=15'00 1 -3897 do. do -0503=14-80 4 -5680 lost when ignited with oxide of lead -0806=14-19 5 -3707 do. do. do. . -0540=14-56 Average, omitting the first, = 14-64 I am indebted to Mr. Madan of Queen's College, Oxford, for the ana- lyses i. and ii. in this Table, and the water-determination in analysis i. of Langite. Like Langite, this mineral also contains traces of iron, lime, and mag- nesia. Of protoxide of iron I found in a very pure crystalline specimen of the mineral 0-14 per cent. Crystals of Brochantite are often mixed with the Waringtonite, and the more amorphous forms of the green substance would seem to be mixtures of the two minerals. The formula 3 Cu" H2' O2+Cu"SO4 + H2O requires — Calculated Average percentage. found. 4 equivalents of copper 12672 = 53' 99 54-48 4 „ oxygen 32 = 13-63 (calc. 13756) 1 „ sulphuric anhydride 40 = J 7'04 1673 4 water . . 36 = 15-34 14-64 23472 100-00 99-606 Like Langite, Waringtonite, though insoluble in water, is readily dissolved by acids and ammonia, and its behaviour before the blowpipe is similar to that of Langite. Its specific gravity is 3'39 to 3'47. Its hardness is 3 to 3'5. It abrades calcite, but not Arragonite. When a crystalline fragment is crushed between a cleavage face of celestine and a 1865.] of the Brochantite Group. 399 smooth surface of porcelain or chalcedony, it leaves the celestine without perceptible abrasion. Brochantite, on the other hand, deeply cuts into that mineral. In comparing the physical characters of these two minerals, one has fur- thermore to observe that, besides their differences in hardness and specific gravity (in Brochantite G=3-87-3'9), their crystallographic habits are entirely dissimilar. Thus if we assume, for comparison's sake, the angle obtained for the normal inclination of the planes 1 1 0, 1 1 0 in Warington- ite to correspond to that between e e or 1 0 I, Fo 1 of Brooke and Miller in Broclmntite, a point of view from which we see the two minerals in the most advantageous orientation for comparison, we shall find that the planes of the form (1 0 1) in Brochantite, like those of (1 1 0) in Waringtonite, are much curved ; the plane I 0 0, however, is a well-marked plane in Brochan- tite, striated parallel to the zone-axis [0 0 1J. In Waringtonite the corre- sponding plane, 0 1 0, is a curved surface without striation. The plane 001 is furthermore a most conspicuous plane in the latter mineral, while the analogous plane 0 I 0 in Brochantite is, I believe, unknown. A mineral, described by Berthier (Ann. Chim. Phys. 1. 360), and one recently analyzed by Domeyko (Annales des Mines, 1864, p. 460), gave the following percentage composition : — Berthier. Domeyko. M. Pisani. Waringtonite. Copper 52-85 55'89 54-9 54-48 Oxygen 13-35 14-15 13'9 13*756 Sulphuric anhydride .. 16-6 16-15 17'2 1673 Water .. . 17'2 13-81 13-2 14-64 100-0 100-00 1-0 99-606 CaO -8 101-0 In the third column of the above Table I have also given the results of M. Pisani's analysis of a green mineral which he found associated with Lan- gite, and which was probably Waringtonite mixed with the ferruginous Kilias (on which it often occurs). He assigned the mineral to Brochantite. Berthier' s mineral from Mexico was probably Waringtonite containing hygrometric moisture, as by deducting two per cent, of water his analysis almost exactly accords with the numbers representing that mineral. The green fibrous mineral from the Cobre mines in the Atacama desert would seem, from the description of the eminent mineralogist of Chili, to be a mixed substance. III. Atacamite. I have mentioned that the first specimen of Langite that came into my hands had upon it small bright green crystals of a mineral with the angles of Atacamite. These angles were the following : — 400 Dr. B. Jones on the Passage of Crystalloids [1865. Corresponding angles Found. in Atacamite. 1 1, 00=63° 48' 63° 20' 1 1, 1 0=36 27 36 18 00, _1 0=56 35 56 10 1 0, 1 1 0 = 66 50 67 40 0 1, 00=52 50 52 50 1 0 1, 0 1 = 74 20 74 20 Seen in polarized light through 100, the normal to 1 0 0 appears to be a bisectrix, and the plane of the optic axes is parallel to the edge 1 10, 100; and the crystal, as seen through 1 0 0, is negative. It is dichroic, exhibiting — C, = plane of polarization parallel to 0 0 1, grass-green, b, =plane of polarization parallel to 0 1 0, more yellowish green. There were but a very few of these minute, in fact microscopic crys- tals ; but two of them I dissolved in nitric acid on a watch-glass, and tested them with nitrate of silver in the field of the microscope. A white cloud was at once struck in the solution, which, while refusing to dissolve in nitric acid, readily yielded to the solvent action of ammonia. This mineral then is Atacamite, as is confirmed by its apple-green streak. Since that time a mine in St. Just has produced this mineral, and I have from Mr. Tailing a specimen from there which contains sulphate as well as chloride of copper. I hope soon to have the opportunity of effecting its analysis from purer specimens than such as have as yet been raised ; for these consist of an intimate mixture, in which Atacamite, indeed, seems to be the preponderating ingredient, but in which, perhaps, Langite and Bro- chantite will prove also to be present. " On the Rate of Passage of Crystalloids into and out of the Vas- cular and Non-vascular Textures of the Body." By HENRY BENCE JONES, A.M., M.D., F.R.S. Received April 26, 1865*. It occurred to me that possibly, by means of the spectrum, I might trace the rate of passage of medicines into the vascular and non-vascular textures, and prove their presence, and determine the time during which they remain in action in some of the tissues far more accurately than had yet been done. I was fortunate enough to obtain the assistance of Dr. A. Dupre, who had already published a paper in the Philosophical Magazine on the presence of lithium and strontium in the waters of London ; and I am greatly indebted to him for carrying out all the suggestions which I thought requisite for proving how soon the salts of lithia pass into the different vascular and non-vascular textures of animals and of man, and how quickly * Read May 4, 1865 ; see Abstract, p. 220. 1865.] into and out of the Vascular and Non-vascular Textures. 401 these salts again pass out and cease to be detectable in the different parts of the body. I shall divide this paper into five sections : — 1 . On the method of analysis, and its delicacy. 2. Experiments on animals to which salts of lithium were given, upon the rate of their passage into the textures. 3. On the rate of the passage of lithia-salts out of the textures. 4. On experiments on healthy persons, and on cases of cataract. 5. On the presence of lithium in liquid and solid food. 1. On the Method of Analysis, and its delicacy. Three methods of preparing the substance to be analyzed were followed, according as much or little lithia was present. When plenty of lithia was present, it was immediately detected in the spectrum by simply touching the substance containing lithia with a red- hot platinum wire. In the case of liquids, a portion of a drop was taken up on the end of the wire, and it was then put into the gas-flame. If no lithia was thus detectable, a larger or smaller portion of the sub- stance was extracted by distilled water twice or thrice, and the liquid was evaporated to dryness, and the residue was then tested. If very little lithia was present, it was necessary to incinerate a larger or smaller portion of the substance, and to treat the ash with sulphuric acid, to exhaust the resulting sulphates with absolute alcohol and evapo- rate the alcohol extract to dryness, and to test the residue for lithia. Kirchhoff and Bunsen state that less than 1,000.000 °^ a milligramme of carbonate of lithia = to about 8,ooo.ooo °f a gram can De detected by the spectrum analysis. To determine the delicacy of the test for the chloride of lithium, the following experiment was made : — One grain of chloride of lithium was dissolved in one litre of water. Of this solution 100 cub. centims. were taken and again diluted to one litre, this latter solution containing O'l grain of chloride of lithium to the litre. When further diluted to five times its bulk, the lithium reaction was still seen faintly on a wire taking up 0'06 grain of solution. The line is most distinctly visible in the evening, in a somewhat dark room. This dilution is equal to O'l grain of chloride of lithium in 5 litres of water, or 1 grain in 50 litres. 1 litre= 15,440 grains, or 50 litres = 7/2,000 grains. In O'OG grain of this solution there are therefore O'OOOOOOOS grain chloride of lithium, or about T^oTo^ToTo1^ °f agram of chloride of lithium. This contains only ^ part of lithium, so that the 72 00*6 Tooth °f a gram °f metallic lithium, when pure, gives the spec- trum reaction. When the chloride of lithium was dissolved in urine, the test was from twice to six times less delicate than in distilled water. 402 Dr. B. Jones on the Passage of Crystalloids [1865. 2. Experiments on animals to which salts of lithium were given, upon the rate of the passage into the textures. Experiment 1 . Two guinea-pigs were fed for several days on the same food. One was killed, and the urine, the nails, hair, blood, bones, muscles, nerves, cornea, and crystalline lens were examined by the spectrum, and no trace of lithium was found anywhere. The other was given half a grain of chloride of lithium for seven days, and for two days one grain. It was then killed, and the lithium was found everywhere, even in the cornea, crystalline lens, hair, and toe-nails. In these it was more distinctly present than anywhere else, so that it probably came from the urine. Experiment 2. Another guinea-pig, fed on the same food as the first two, was given only half a grain of chloride of lithium for three days. The third morning the lithium was detectable, by analysis, in the hair ; the fourth day it was killed, and the lithium was found everywhere, as in the last instance. Experiment 3. Another, after the hair and nails had been examined for four days and no lithium found, was given three grains of chloride of lithium. In two hours and a half lithium was detected in the hair of the belly, though in six hours none was found in the hair of the back ; much more was then in the hair of the belly. In twenty- six hours it was killed. Lithium was found everywhere, — both in the outer and inner part of the lens very distinctly, and in the cartilage of hip- and knee-joints. The spleen and liver seemed to have less lithium than the vitreous and aqueous humour and the lens. Experiment 4. A guinea-pig was given three grains of chloride of lithium, and in twenty-four hours it was killed. Lithium was found in the cartilage of the hip- and knee-joints, in the centre of the lens, in the nails, and in the outer moisture of the eye. Experiment 5. To another, the hair of which gave no trace of lithium, were given three grains of chloride of lithium, and it was killed in eight hours ; as usual, lithium was found in all the organs — by far the most in the kidneys. Little was found in the blood. It was quite evident in the cartilage of the hip-joint, and very distinct in the outer layer of the crystalline lens, but none at all could be found in the centre of the lens. Both lenses were examined more than six different times with the same result. Experiment 6. In a guinea-pig, much younger than the last, which was killed eight hours after three grains of chloride of lithium, the whole lens was penetrated, — the smallest particle, even one-twentieth the si/e of a pin's-head, taken from each part of the lens, showing the lithium distinctly. The whole lens of another pig that had taken no lithium was- burnt, and did not show the slightest trace of lithium. Experiment 7- Another guinea-pig was given three grains of chloride of lithium, and it was killed in four hours. Lithium was found in the fibrin, serum, and corpuscles of the blood, in the cartilage of the hip-joint, and in 1865.] into and out of the Vascular and Non-vascular Textures. 403 the lens, even in its most central part. There was scarcely any difference between the inner and outer part. The vitreous and aqueous humours showed much more evidence of lithium than the lens itself did. Experiment 8. A guinea-pig, the urine of which gave no trace of lithium, had three grains of chloride of lithium, and was killed in two and a half hours. The lithium was found in the cartilage of the hip-joint dis- tinctly but faintly. The blood showed the lithium very distinctly, much more so than in any of the previous experiments. The outer portion of the lens showed lithium, though but slightly. The inner portions of the lens showed more. The vitreous and aqueous humours showed lithium very distinctly. Experiment 9. A large guinea-pig was given three grains of chlo- ride of lithium, and it was killed in an hour. Lithium was found in the blood, urine, and nails very distinctly ; in the cartilage of the hip- and knee-joints very faintly ; in the vitreous and aqueous humours of the eye very distinctly. No lithium was found in the lens, not even when half the lens was taken for a single experiment. The stomach contained food. Experiment 10. Another guinea-pig was killed an hour after the same dose. The lithium was found strongly in the blood, bile, liver, and kidney. Traces occurred in the brain and in the cartilage of the hip-joint. It was present distinctly in the humours of the eye and in the lens. The differ- ence between the inner and outer part of the lens was very marked. The second eye was not examined for more than fourteen hours after the first eye. After this time the centre of the lens contained as much lithium as the outer part did. The stomach contained water. Experiment 11. A young guinea-pig, fasting, was given three grains of chloride of lithium, and thirty-two -minutes afterwards it was killed. Li- thium showed faintly in the cartilage of the hip-joint ; very distinctly in the humours of the eye ; distinctly in the outer part of the lens, very faintly in the inner part ; nearly the whole of the inner part had to be burnt to give the appearance. Lithium was very distinct in the blood, and re- markably so in the nails. Experiment 12. Another young guinea-pig, fed in the same way, and bought at the same place as the two former, was killed without taking any lithia. No lithium was found anywhere. The whole of the spleen, one kidney, and one lens were incinerated, and each ash was used for a single experiment, and in no instance was lithium found. There was no lithium in the cartilage of the hip-joint, nor in the blood, nor in the nails. Experiment 13. A very young and small guinea-pig that had been kept fasting for thirty-six hours, was given three grains of chloride of lithium, and it was killed in half an hour, the urine having been previously examined, and no lithium found in it. Very much lithium was found in the blood and in the urine ; very slight traces in the cartilage and in the brain. The lens showed no lithium when incinerated entire, but the aqueous extract of the lens showed minute traces of lithium. 404 Dr. B. Jones on the Passage of Crystalloids [1865. Experiment 14. An old guinea-pig, also fasting for about thirty-six hours, was given the same quantity of chloride of lithium, and was also killed in half an hour. No lithium could be detected before the dose in the urine, nor in the toe-nail of one leg. After taking the lithium, the animal was wrapped up in a cloth, the leg only being left out, to prevent it from licking the toe ; after death, the nails of this leg showed that some lithium was there. The sciatic nerve showed traces of lithium. The cartilage of the hip-joint, when touched with red-hot wire, showed no lithium, but scrapings from the surface showed traces of lithium. The humours of the eye showed traces of lithium, but the lens showed no lithium even in the watery extract. The brain showed only exceedingly faint traces of lithium. The stomach was almost completely empty. Experiment 15. A guinea-pig was kept fasting for twenty-four hours ; it was then given three grains of chloride of lithium, and it was killed in a quarter of an hour. Lithium was found in the bile, liver, kidney, and blood very distinctly ; very faintly in the brain and in the cartilage of the hip-joirt, and in the humours of the eye. None was found in the lens. The stomach contained only some water, no solid food. Experiment 16. Three fresh guinea-pigs were taken, one was killed without taking any lithium. The urine showed no lithium in one drop, but the ash of the urine showed traces of lithium. No lithium could be detected in any of the organs, not even by treating the ash of the kidney with sulphuric acid and alcohol. The two remaining animals were each given one quarter of a grain of chloride of lithium. The first was killed in five and a quarter hours afterwards. All the organs, except the lens of the eye, showed lithium by simply touching them with the red-hot wire. The urine and the bile showed the lithium very distinctly. The blood showed lithium faintly. The vitreous and aqueous humours showed traces of lithium. An aqueous extract of the lens showed no lithium. The animal was a large and old one, and the stomach was nearly empty. The second was killed twenty-four hours after one quarter of a grain. None of the organs showed any lithium by simply touching them with a red-hot wire. The ash of the kidney showed traces of lithium, and so did the ash of part of the liver. No lithium could be detected either in the vitreous and aqueous humour or in the lens ; the urine and the bile showed lithium in one drop, but only faintly. Possibly the lithium had not been absorbed in this case. The state of the stomach, as regards food, was not recorded. " It follows from these experiments, that when no lithium is taken no lithium can be found in the different textures, but that even in a quarter of an hour three grains of chloride of lithium given on an empty stomach may diffuse into the cartilage of the hip-joint and into the aqueous humour of the eye. In very young and very small guinea-pigs the same 1865.] into and out of the Vascular and Non-vascular Textures. 405 quantity of lithium in thirty or thirty-two minutes may give traces of lithium in the lens ; but in an old animal in this time it will have got no further than the aqueous humour. If the stomach be empty, in an hour the lithium may be very evident in the outer part of the lens, and very faintly in the inner part ; but if the stomach be full of food, the lithium does not in an hour reach the lens. Even in two hours and a half lithium may be more marked in the outer than in the inner part of the lens. In four hours the lithium may be in every part of the lens, but less evidence of its presence will be obtained there than from the humours of the eye. In eight hours even, the centre of the lens may show less than the outer part. In twenty-six hours the diffusion had taken place equally through every part of the lens. Even one quarter of a grain in twenty-four hours showed lithium everywhere except in the lens. Experiment 17. To endeavour to determine the different rate of ab- sorption and excretion in young and old animals, four guinea-pigs were taken ; two were young, and two were old. The four, after fasting for fif- teen hours, were each given two grains of chloride of lithium. Two of them, one young and one old, were killed in six hours. The young animal showed lithium distinctly in the outer and inner part of the lens, and also in the cartilage of the hip-joint, when touched with a red-hot wire. The stomach was about half full of food. The old one showed lithium distinctly in the outer part of the lens, but scarcely the faintest trace in the inner part. The cartilage of the hip-joint showed lithium quite as distinctly as the cartilage of the young Pig- The other two guinea-pigs were kept. After forty-eight hours, the urine of both showed lithium very distinctly in one drop. Six days after- wards, the urine of the young animal still showed lithium faintly in each drop. The urine of the old one found in the bladder after its death showed lithium faintly in each drop. Both were killed on the sixth day, and no lithium could be detected in the alcoholic extracts of the kidneys, livers, or lenses of either. A short series of experiments were made with the view of determining the rate at which the salts of lithium diffuse into the textures when the lithium is injected into the skin instead of passing through the stomach. Three grains of chloride of lithium in solution were injected into the skin of the back of the neck of a guinea-pig, and the animal was killed in twenty-four minutes. The urine, bile, kidney, and liver showed lithium very distinctly. The cartilage of the hip-joint showed lithium distinctly when touched with a red-hot wire. The aqueous humour showed lithium very distinctly, but the lens, when washed, showed only a very minute trace ot lithium when the entire lens was taken at one time on the wire. The toe-nails showed lithium very distinctly. VOL, XIV. 2 H 406 Dr. B. Jones on the Passage of Crystalloids [1865. Another had three grains injected under the skin of the neck, and it was killed in ten minutes. The humours of the eye showed lithium distinctly, but the aqueous humour showed decidedly more than the vitreous humour. The inci- nerated aqueous extract of the lenses showed lithium very faintly. The large nerves of the leg also showed lithium very faintly. Another guinea-pig had a grain and a half of chloride of lithium injected under the skin of the neck, and in five minutes it was killed. The aqueous humour showed lithium distinctly. The vitreous humour showed none. The blood and bile showed lithium very distinctly. The kidney and urine showed lithium faintly, and the liver very faintly. In another pig three grains of chloride of lithium were injected into the skin of the neck, and the animal was killed in four minutes. The blood and the bile showed lithium very distinctly ; the blood showed it rather more than the bile. The bladder contained only a few drops of urine, which showed lithium distinctly. The kidney showed lithium fairly well. The liver showed the lithium only very faintly, and in some parts not at all. The aqueous humour showed lithium distinctly. The vitreous humour showed no lithium. So that, when injected under the skin, 3 grains in twenty-four minutes gave lithium in the lens and everywhere. 3 grains in ten minutes gave lithium in the lens and everywhere. 1J grain in five minutes gave lithium in the aqueous humour and in the bile. 3 grains in four minutes gave lithium in the aqueous humour and in the bile. 3. Experiments on the Rate of Passage of the Lithium out of the Textures. Experiment 18. Five guinea-pigs were given two grains of chloride of lithium each. They were killed at different periods ; the first in six hours. The smallest particle of the lens showed the lithium very dis- tinctly ; a decided difference, however, was detectable between the inner and the outer part. The cartilage of the hip-joint showed lithium very distinctly when touched with the red-hot wire. All the organs and the blood showed lithium very abundantly. The stomach contained very little solid food, but was half full of liquid. The second and third were killed in twenty-four hours. The lenses of both showed the lithium very distinctly; no difference was perceptible between the inner and the outer part. The cartilage of the hip-joint showed no lithium when touched with the red-hot wire ; but a small portion taken off the surface showed lithium distinctly. The fourth guinea-pig was killed in forty-eight hours. The lens showed 1865.] into and out of the Vascular and Non-vascular Textures. 407 lithium very distinctly. A small piece taken from the cartilage of the hip-joint showed only traces of lithium. The fifth was killed in ninety-six hours. The lens showed no lithium even when a considerable proportion of it was taken for one experiment. The aqueous extract of half one lens showed no lithium. A small portion of the cartilage of the hip-joint showed no lithium. The urine showed lithium very distinctly even in one drop. Experiment 19. Six fresh guinea-pigs were taken. The first was killed and examined, having had no lithium. The two lenses, incinerated and treated with sulphuric acid and alcohol, showed no lithium. The ash of the kidney showed no lithium directly, but when treated with sulphuric acid and alcohol, showed a distinct trace of lithium. The five others were given each one grain of chloride of lithium. The first was killed five and a half hours after the dose. The cartilage of the hip-joint showed lithium faintly when merely touched with a red- hot wire. The lens showed lithium distinctly in the outer part, scarcely a trace in the inner part. The vitreous and aqueous humours showed lithium very distinctly. The stomach was quite full. The second was killed twenty-four and a half hours after the lithium was taken. The cartilage of the hip-joint showed no lithium even in a small particle scraped off the surface. The lens still showed lithium dis- tinctly, though less so than in the first; no difference was perceptible between the inner and the outer portion. The third was killed in forty-eight hours. The lens showed no lithium in a small particle taken on a loop of the wire. The aqueous extract of the lens showed only faint traces of lithium. The urine showed lithium very distinctly in a single drop. The fourth was killed in seventy- two and a half hours. The lens showed no lithium when the ash was treated with sulphuric acid and alcohol. The ash of the kidney showed no lithium directly, but when treated with sulphuric acid and alcohol, showed traces of lithium. The urine still showed lithium distinctly in one drop. The fifth guinea-pig : on the seventh day after the dose, the urine showed lithium in one drop ; ninth day, still faint traces of lithium in the urine ; eleventh day, urine directly shows no lithium, but the ash still shows faint traces ; thirteenth day, ash of urine shows no lithium, but alcoholic extract shows lithium distinctly ; fourteenth day the same ; sixteenth day the same ; thirty-sixth day, when killed, no lithium could be detected in the bones, nerves, lens, or vitreous or aqueous humours, nor in the urine, kidney, or liver. Experiment 20. Two guinea-pigs, in the urine of which no lithium could be detected, were given each half a grain of chloride of lithium. In three hours and fifty minutes afterwards one was killed. The car- tilage of the hip-joint showed no lithium when simply touched with a red- 2H2 408 Dr. B. Jones on the Passage of Crystalloids [1865. hot wire. Scrapings from the surface of the cartilage showed faint traces of lithium. The sciatic nerve, humours of the eye, and the brain showed faint traces. The muscles of the thigh showed the lithium much more distinctly than the sciatic nerve. The lens showed lithium very dis- tinctly in the aqueous extract, but not otherwise. The blood and bile were very rich in lithium. The stomach was moderately full of food. The other animal, which was given half a grain, was kept until the lithium ceased to appear in the urine. Fourth day. Lithium distinctly in the urine. Tenth day. Urine showed exceedingly minute traces of lithium. Eleventh day. Still traces. Thirteenth day. Urine shows no lithium in the quantity adhering to the wire. Fourteenth day. Still lithium in the alcoholic extract. Twenty-seventh day. Still traces of lithium. Thirtieth day. The animal was found dead. The ash of the urine found in the bladder (about a quarter of an ounce) showed no lithium. The alcoholic extract of the ash showed lithium faintly. The alcoholic extract of the ash of one kidney showed no lithium. And the alcoholic extract of the two lenses showed no lithium. Experiment 21. Two guinea-pigs, the urine of which contained no li- thium, were each given one quarter of a grain of chloride of lithium. One was killed in four hours and thirty-five minutes. Lithium was found very faintly in the spleen, very distinctly in the blood, in the urine, and in the bile. Faintly in the sciatic nerve and in the brain. Very faintly in the scrapings of the cartilage. Pretty distinctly in the vitreous and aqueous humours, but very faintly in the aqueous extract of the lens. The stomach was moderately full. The other was kept until the lithium ceased to appear in the urine. Second day. Lithium very distinctly. Fourth day. Minute traces of lithium. Sixth day. A drop or two of urine shows no lithium, but on evaporating and incinerating one-twelfth of an ounce, the ash shows lithium very dis- tinctly. Seventh day. Lithium still distinct in the ash. Eighth day. Still in the ash. Tenth day. Ash of urine shows only the merest trace. Eleventh day. Ash of urine shows no lithium ; but when treated with sulphuric acid and alcohol, lithium is still distinct. Thirteenth day. Still lithium in one quarter of an ounce. Fourteenth day. Alcoholic extract from one-eighth of an ounce shows no lithium. Sixteenth day. The animal was killed. The fluids and organs were incinerated, the ash treated with sulphuric acid, excess of acid driven off 1865.] into and out of the Vascular and Non-vascular Textures. 409 and the dry residue extracted with absolute alcohol, alcoholic extract evaporated, and dry residue tested. The two lenses gave extremely feeble traces of lithium. One-eighth of an ounce of urine and bile gave traces of lithium. Ninety grains of liver gave traces. One quarter of an ounce of blood gave no lithium. An entire kidney, weighing ninety grains, distinctly contained lithium. Experiment 22. Two guinea-pigs, the hair and nails of which showed no lithium, were given each three grains of chloride of lithium. In the first, in two hours no lithium was in the hair. In four hours lithium was in the hair of the belly, but scarcely perceptible in the hair of the head. In twenty-four hours it was very distinct in the hair of the belly and the head, and in the nails. For five days it was detected in each drop of the urine. Ten days afterwards the urine showed lithium very distinctly ; only after thirty-two days was lithium absent from a few drops of the urine. The thirty-third day after the dose the animal was killed. No lithium was found in the bile, liver, blood, lens, kidneys, spleen, or other parts, by simply taking a small piece of the organ on a red-hot wire. The evaporated aqueous extract of the two lenses showed no trace of li- thium ; when, however, the two kidneys were incinerated, the ash treated with sulphuric acid, the resulting sulphates exhausted with absolute alcohol and the alcoholic extract evaporated to dryness, lithium was easily detected in the residue. A portion of the liver, treated in the same manner, also yielded lithium. The second guinea-pig gave traces of lithium in the urine when one- eighth of an ounce was evaporated and treated with sulphuric acid and alcohol, thirty-nine days after the lithium was taken. It follows from these experiments on the rate of passage of lithium into and out of the body, that — With three grains of chloride of lithium, a young guinea-pig in half an hour had lithium in the watery extract of the lens. An old guinea-pig in the same time had no lithium in the lens. With two grains, a young guinea-pig in six hours had lithium dis- tinctly in all parts of the lens. An old guinea-pig had in the same time scarcely any lithium in the inner part, but some in the outer part of the lens. With the same quantity, in six days neither a young nor an old guinea- pig gave any trace of lithium in the alcoholic extract of the kidney, liver, or lenses. When two grains of chloride of lithium were taken, after six hours the lithium was more distinct in the outer than in the inner part of the lens. In twenty-four hours no difference in the different parts of the lens was detectable. In forty-eight hours still no difference was observed. In ninety-six hours (four days) no lithium was detectable in the lens or in a cartilage of a joint ; still the urine showed lithium very distinctly even in one drop. 410 Dr. B, Jones on the Passage of Ci-ystalloids [1865. After one grain of chloride of lithium, in five hours and a half the lithium was more distinct in the outer than in the inner part of the lens. In twenty- four hours and a half there was no difference throughout the lens. In forty-eight hours the watery extract of the lens showed faint traces of lithium. In seventy-two hours and a half (three days) the alcoholic ex- tract of the lens showed no lithium. The urine still showed lithium dis- tinctly in one drop, and continued to do so for seventeen days in the alcoholic extract. After a quarter of a grain, in five hours and thirty-five minutes lithium was distinct in the vitreous and aqueous humours, and very faintly in the lens. After sixteen days, the minutest traces of lithium were detected in the lens, the liver, and the kidneys, but no trace could be found in the blood. (This animal had perhaps somehow eaten the minutest quantity of lithia in the food*.) After half a grain of chloride of lithium, in three hours and fifty minutes traces of lithium could be found in the lens, and for thirty-seven or thirty- eight days traces of lithium could be found in the urine. After three grains of chloride of lithium, in four hours^ lithium was in the hair of the belly, and for thirty-two days the urine showed lithium very distinctly. The thirty-third day after the lithium the lens was found to contain minute traces of lithium, and after thirty-nine days the lithium was in the alcoholic extract of the urine. 4. Experiments on the Bate of Passage of Lithium through the Human Body, and into and out of the Crystalline Lens. Experiment 1 . A man took ten grains of carbonate of lithia dissolved in water, four hours after his midday food. In five minutes no lithium could be detected in the urine. In ten minutes lithium was evident. In eighteen hours it was present in the nails of the hands and feet, and in the hair of the beard and body ; apparently most where there was most perspiration. No lithium could be found in the hair of the head or whiskers. In forty-two hours very perceptible. In sixty-six hours another dose of ten grains was taken. In ninety hours lithium was detectable in the hair of the head. For three days after the second dose it was perceptible in one drop of the urine, but rather doubtful in the hair and in the nails. For six days after the second dose lithium was detectable in the urine. For eight days after, no lithium could be detected when the eighth of an ounce of urine was evaporated. * The skin of guinea-pigs throws off lithium, and it collects on the hair and nails, so that it is possible for the animal to redose itself with lithium from its own body, and thus to keep lithium passing in and out of the textures much longer than if a single dose only were taken. 1865.] into and out of the Vascular and Non-vascular Textures. 411 Twelve days afterwards, though no lithium was in the urine or the hair of the head or whiskers, it was detectable in the hair of the body. Experiment 2. The same man three hours after breakfast took ten grains of carbonate of lithia. In five minutes lithium was just perceptible in the urine. In ten minutes extremely distinct in one drop of the urine. In twenty-four hours very distinct in the urine. Fourth day. Traces of lithium when the urine was concentrated by eva- poration. Fifth day. Less perceptible in evaporated residue. Sixth day. No lithium could be detected in evaporated urine. 'Experiments. The same man took ten grains of carbonate of lithia after fasting for seven hours. The urine was passed every second minute after taking the lithia. Second, fourth, and sixth minute, no lithium. Eighth minute, traces of lithium very slight. Tenth minute, lithium distinctly present. Third day afterwards lithium very distinct. Fourth day. Lithium faintly found in each drop of urine. Fifth day. Lithium very faint in each drop. Sixth day. Only the merest trace. Seventh day. No lithium in the eighth of an ounce evaporated to a few drops. Eighteenth day. Two ounces of urine incinerated, and the ash heated with sulphuric acid and alcohol, showed no lithium. Twenty-first day. Nails of the hands and feet still show lithium. Experiment 4. The same man, two hours and a half after a little food, took ten grains of chloride of lithium : one nail on the hand and one on the foot were varnished before taking the lithium. Second and fourth minute afterwards no lithium was in the urine. Sixth minute, traces of lithium. Eighth minute, distinctly present. Tenth minute, very distinctly. Twenty-five hours afterwards none of the nails showed any lithium. Forty-four hours. Scrapings of the unvarnished nails on the hands and feet showed lithium distinctly. The further the scraping was carried the less lithium was found. The scrapings of the varnished nail of the hand shows only traces of lithium. The varnished nail of the foot has no lithium. A small particle of the skin from the hand or foot shows lithium distinctly. Perspiration shows lithium distinctly. The hair of the head or whiskers shows no lithium. Third day. Nails the same as yesterday. The unvarnished nails show lithium ; the varnished, none. Urine shows lithium most distinctly. Fourth day. Urine shows lithium in one drop. Fifth day. Urine still shows minute traces of lithium in one drop. 412 Dr. B. Jones on the Passage of Crystalloids [1865. Sixth day. Urine shows no lithium. Ash of the urine shows faint traces of lithium. Seventh day. Ash of urine shows no lithium. Alcoholic extract shows traces. Eighth day. Alcoholic extract from one ounce of urine still shows traces of lithium. Ninth day. Alcoholic extract from one ounce of urine shows no lithium. Experiment 5. A boy, aged sixteen years, took five grains of chloride of lithium, and the urine was passed every second minute. Half an hour previously he had eaten some bread and butter. No lithium could be de- tected in the urine previous to the taking of the dose. Second minute, no lithium in the urine. • Fifth minute, none. Ninth minute, none. Tenth minute, very faint traces of lithium. Thirteenth minute, lithium very distinctly present. After twenty-four hours lithium still very distinct. Second, third, fourth, and fifth day. Still very distinct. Seventh day. No lithium was found in the evaporated residue. The ash of the residue shows very slight traces. Eighth day. The alcoholic extract from one ounce of urine shows no lithium. Experiment 6. The same boy had his hair, nails, and urine examined, and no lithium was found. Five grains of carbonate of lithia was then given to him. In two minutes, five minutes, ten minutes, no lithium was found in the urine. In twenty minutes lithium was distinctly present. In eighteen hours the lithium was found in the nails, none in the hair of the head. In thirty-two hours, still none in the hair of the head. Very distinctly in the root and tip of the nails. Another five grains of carbonate of lithia was then given. In nineteen hours lithium was detected in the hair of the head. In four days a drop of the urine showed lithium very distinctly, as did the hair and nails. In five days the same. In seven days one drop of the urine shows no lithium, but if the urine - is slightly concentrated by evaporation, lithium is still perceptible. In eight days one-eighth of an ounce evaporated still shows slight traces. In nine days no lithium in one-eighth of an ounce of urine. Experiment 7. The same boy took five grains of carbonate of lithia, but he omitted previously to empty his bladder. In five minute?, lithium not yet detectable in the urine. 1865.] info and out of the Vascular and Non-vascular Textures. 413 In ten minutes lithium very distinctly present in one drop of the urine. Four days afterwards traces of lithium still in the urine. Five days afterwards slight traces in one-eighth of an ounce of urine when evaporated. In six days afterwards no lithium perceptible in the urine. Experiment 8. Twenty-five grains of chloride of lithium were dissolved in one gallon of water, and the feet and ankles of a man were kept in the solution for two hours ; at the end of this time the urine was passed and examined for lithium, and no trace could be found in the aqueous extract of the ash of one quarter of an ounce of urine. These experiments agree very closely with some which I made many years since on a full-grown German who had an open bladder, admitting the urine to be caught as it came from the kidneys. Feb. 24, 1852. At 8.45 A.M. he took two cups of black coffee and nothing else. 9.30 to 9.50. Urine was caught, and it contained no trace of iron. 9.50. Protosulphate of iron, 6-7 grains, free from persulphate was taken in two ounces of distilled water. 9.55. Urine caught and contained no iron. 1 0. No iron as peroxide. Present as protoxide. 10.5. Slightest trace of peroxide. Protoxide distinct. 10.10. Slightest trace of peroxide. Protoxide distinct. 10.20. Slightest trace of peroxide. Protoxide less distinct. 10.30. „ ,, Protoxide less distinct. 10.40. ,, „ Slightest trace of protoxide. 11. „ „ No trace. 11.10. „ „ No trace. Feb. 26. The same patient. At 8 A.M. two cups of black coffee and nothing else. 10.20 to 10.30. Urine caught and no trace of iron found. 10.30. Sulphate of protoxide of iron four grains, given in one ounce of distilled water. 10.31. No trace of iron in the urine. 10.34. No trace. 10.35. No trace. 10.36. No trace. 10.37. Slightest trace of protoxide of iron in the urine. No peroxide. " 10.39. No trace. 10.40. No trace. March 2nd. The same patient. At 8 A.M. two cups of black coffee and nothing else. 9.34 to 9.40. Urine collected and no trace of iron found. 9.40. Sulphate of protoxide given, seven grains in two ounces of dis- tilled water. 9.42. None. 414 Dr. B, Jones on the Passage of Crystalloids [1865. S.45. Noiie. 9.47-|. None. 9.50^. A trace. 9.52£. A trace. 9.55. Good. 9.57|. Doubtful. 10. Doubtful. 10.5. More distinct. 10.10. Doubtful. 10.15. Doubtful. March 19. At 8 A.M. two cups of black coffee without milk, nothing else taken. Urine from 9.50 to 9.56 collected ; contained no iodine. One grain of iodide of potassium dissolved in one ounce of water was then taken. 9'58. No iodine. 9.59. No iodine. 10. None. 10.1. None. 10.2. None. 10.3. None. 10-4. None. 10-5. None. 10.6. None. 10.8. Trace of iodine. 10.10. Very marked iodine. 10.15. Very marked. So that one grain of iodide of potassium in one ounce of water was de- tected in the urine in twelve minutes, and was very marked in fourteen minutes. Iron was detected once in seven minutes and twice in ten minutes, and it was very distinct in fifteen minutes. Professor Mulder also made many experiments on this patient, but I am unable to find any account of his results. In the 'Medical Gazette' for 1845, pp. 363 & 410, Mr. Erichsen gives some experiments he made on a boy of thirteen who had an open bladder. He states that twenty grains of ferrocyanide of potassium were detected in one minute in the urine. The stomach was fasting, and the salt was dis- solved in three ounces of water. Forty grains taken three quarters of an hour after a full meal were only detected after thirty-nine minutes. Forty grains in four ounces of water were twice detected in two minutes, and no trace could be found after twenty-four hours ; once in two minutes and a half ; once in six minutes and a half ; once in fourteen minutes ; once in twenty-seven minutes ; and once in thirty-nine minutes. Twenty grains of ferrocyanide he once detected for twenty-eight hours. It follows from these experiments that ten grains of carbonate or chloride of lithium, taken two and a half, three, or four hours after food by a man, 1865.] into and out of the Vascular and Non-vascular Textures. 415 require between five and ten minutes to pass from the stomach to the urine, and this quantity of carbonate or chloride of lithium will continue to produce traces of lithium in the urine from six to seven, or even eight days. Five grains of chloride or carbonate of lithia, taken shortly after food by a boy, gives no appearance in the urine until from ten to twenty minutes, and this quantity continues to pass out for five, seven, or eight days. Experiments made by the ordinary mode of analysis showed that Four grains of sulphate of the protoxide of iron, taken almost fasting by a man, gave a trace in the urine in seven minutes. Seven grains gave distinct appearance in ten minutes and ten minutes and a half. One grain of iodide of potassium, taken by the same man fasting, appeared in the urine in twelve minutes. Experiments on the Kate of Passage of Lithium into and out of the Crystalline Lens. Through the kindness of Mr. Bowman and Mr. Critchett at the Moor- fields Ophthalmic Hospital, lithia water, containing variable quantities of lithia, was given to different patients about to be operated on for cataract. Experiment 1 . The hard cataracts from two patients who had taken no lithia water were examined ; no trace of lithium could be found in either lens. Experiment 2. The hard cataracts from two other patients who had no lithia water were examined ; an aqueous extract of each lens was made ; one showed the most excessively feeble lithium line ; the other lens did not give the slightest indication. Experiment 3. The hard cataracts of two other patients who had taken no lithia water were examined ; the alcoholic extract of the ash, after treat- ment with sulphuric acid, showed no lithium in either lens. The lens of a third patient was examined when no lithia water had been taken, and the alcoholic extract showed no lithium. Experiment 4. The lens of a man aged seventy was extracted twenty- five minutes after he had taken twenty grains of carbonate of lithia in water on an empty stomach ; no lithium could be detected in the lens. Experiment 5. A woman, set. sixty-four, at 9 A.M. took twenty grains of carbonate of lithia in water; both lenses were extracted at 11| A.M. the same day. Neither of the lenses showed any lithium when touched with a red-hot wire, but the aqueous extract of one lens showed lithium faintly, and the aqueous extract of the other lens showed lithium distinctly. Experiment 6. An eye was removed three hours after twenty grains of carbonate of lithia had been taken ; the lens was removed half an hour afterwards, and on examination every portion of the lens contained lithium. The circulation through the eye had been healthy, and the lens itself was clear. Experiment 7. The soft lens of a girl aged fourteen was examined after 416 Dr. B. Jones on the Passage of Crystalloids [1865. ten grains of carbonate of lithia in water had been taken five hours before the operation, and the same quantity four hours before extraction. The smallest fraction of the lens showed the lithium distinctly. Experiment 8. Another patient with two soft cataracts took twenty grains of carbonate of lithia seven hours before one operation ; but the capsule of the lens had been previously broken, so as to expose the cataract to the aqueous humour. Lithium was found very distinctly even in the smallest particle of the cataract. Four days after the first operation the capsule of the other lens was broken, so as to expose the cataract to the aqueous humour ; and seven days after the first operation the second operation was performed. In this cataract not the slightest trace of lithium could be found. A woman with diseased heart drank some lithia water, containing fifteen grains of citrate of lithia, thirty-six hours before her death; and six hours before death she drank the same quantity. After death the crystalline lens, the blood, and the cartilage of one joint were examined for lithium. The cartilage showed lithium very distinctly ; the blood showed lithium very faintly ; and when the entire lens was taken for a single examination, the faintest possible indications of lithium were obtained. . Another patient five and a half hours before death drank lithia water containing ten grains of carbonate of lithia. After death the cartilage of one joint and the crystalline lens were examined. The cartilage showed lithium very distinctly. When half the lens was taken for a single analysis, only very faint traces of lithium could be found. When no lithia had been taken, seven cataracts were examined most carefully, and one only showed an exceedingly feeble trace of lithium. When twenty grains of carbonate of lithia were taken twenty-five minutes before the operation, the lens showed no lithium ; the same quantity taken two and a half hours before, showed lithium in the watery extract ; three an da half hours before, showed lithium in each particle; between four and five hours before, the same ; seven hours before, the same ; seven days before, not the slightest trace of lithium. Thirty grains of carbonate of lithia, taken between six and thirty-six hours before death, showed the faintest indications of lithium in the lens. Ten grains of carbonate of lithia taken five and a half hours before death, gave only faint traces of lithium in the lens. On the Passage of Solutions of Lithium through the Textures after death. A sheep's eye was examined after death and no lithium could be detected in any part. Two other eyes were placed in a solution of chloride of lithium containing one grain to one litre of water. Twenty-three hours afterwards the lithium was found to have penetrated through the entire 1865.] into and out of the Vascular and Non-vascular Textures. 417 eye. There was, however, a perceptible difference between the amount of lithium in the inner and outer part of the lenses. Two other sheep's eyes had a small portion of the cornea in front and the sclerotic removed at the back ; they were then placed in a moderately strong solution of chloride of lithium, and the aqueous humour was examined from time to time. After eighteen hours the aqueous humour showed lithium distinctly, and when the lens was extracted the lithium was found throughout its substance. Two other eyes were placed whole in a solution containing one-tenth of a grain of chloride of lithium to one litre of water. In twenty-four hours the lithium had penetrated the entire eye. No difference was perceptible in different parts of the lens. The rate at which a solution of chloride of lithium diffused through the stomach of a fresh-killed guinea-pig which had taken no lithium was de- termined. A solution of one grain of chloride of lithium in twenty grains of water was put into the stomach, and it was hung up so that the solution gravi- tated to the lowest part. The outer side of the stomach opposite the solution was touched from time to time with a loop of platinum wire, which was afterwards tested for lithium. In first minute. No lithium came through the stomach. In second minute. No lithium. In third minute. No lithium. In fourth minute. No lithium. In fifth minute. No lithium. In sixth minute. Traces of lithium. In seventh minute. Traces of lithium. In eighth minute. Lithium was very distinct. The stomach of another guinea-pig was filled with a solution of lithium containing one grain of lithium in about half an ounce of water. The stomach was entirely filled and laid flat on a plate. The ends of the stomach and round the side showed lithium coming through in four minutes. The upper part of the stomach showed the lithium coming through in fifteen minutes. 5. On the Presence of Lithium in Solid and Liquid Food. An ounce of each substance was taken. It was dried or evaporated, and incinerated carefully at a low red heat in a muffle on a platinum tray. The ash was tested for lithium first by taking a small fraction on a loop of a platinum wire into the flame of the spectroscope. When no lithium was thus detected, the ash was treated with sulphuric acid, and heated to expel the excess of acid ; the dry residue was extracted with absolute alcohol, the solution filtered, evaporated to dryness, and the residue taken up in a drop of water and tested by the spectroscope. 418 Dr. B. Jones on the Passage of Crystalloids [1865. Potatoes. In ash direct. In alcoholic extract. No. 1. No lithium. No lithium. 2. „ ,, 3. » » 4. „ Lithium distinctly. 5. „ No lithium. Apples. No. 1. >} » 2. » 3. „ Lithium distinctly. 4. Trace of lithium. Carrots. No. 1. „ No lithium. 2. » j> Bread. No. 1. „ Slight traces of lithium. 2. „ Traces of lithium. 3. „ Lithium distinctly. Savoy Cabbage. No. 1. Lithium distinctly. 2. No lithium. Lithium shown distinctly. Tea. No. 1. » » 2. „ Lithium very faintly. 3. „ Lithium very distinctly. 4. Faintly. 5. „ „ 6. 5» » 7. „ No lithium. 8. „ Faintly. 9. ,, No lithium. 10. „ Very distinctly. Coffee. No. 1. „ Very faintly. 2. » 3. „ No lithium. 4. „ Lithium* distinctly. 5. „ Very distinctly. "Wines : in almost all cases the ash gave direct evidence of the presence of lithium. - Port Wines. No. 1. Small traces oflithium. 2. Faintly. 3. Very faintly. Lithium exceedingly distinct. 1865.] into and out of the Vascular and Non-vascular Textures. 419 Port wines. 4. 5. 6. Sherry. No. 1. 2. 3. 4. 5. 6. French Wines. No. 1. (red). 2. (white). 3. (champagne) In ash direct. Very faintly. No lithium. Lithium extremely brightly. Faintly. Exceedingly faintly. Very faintly. Faintly. Distinctly. Lithium very distinctly. Extremely distinctly. Very brightly. In alcoholic extract. Lithium exceedingly distinct. Very faintly. Very distinctly. Rhine Wines. No. 1. 2. 3, 4. 5. 6. 7. 8. Ale. No. 1. 2. 3. Porter. No. 1. 2. 3. Lithium exceedingly faintly. Lithium distinctly. Very faintly. Distinctly. Faintly. Distinctly. Faintly. No lithium. Lithium faintly. No lithium. Lithium faintly. „ No lithium. ,, Lithium distinctly. In the Philosophical Magazine, vol. xx. Messrs. A. and F. Dupre gave the spectrum analysis of London waters. All the different waters examined gave lithium. The shallow waters appear to be richer in lithium than the deep-well waters. The different waters examined were : Thames water at high and low tide at Westminster Bridge ; the water from Chelsea and Lambeth Water-Companies ; New River water ; Duck Island well, in St. James's Park ; Pump in Lincoln' s-Inn. These were above the London clay. Burnett's Distillery and Whitbread's Brewery : from the sand above the Chalk. Guy's Hospital well and Trafalgar Square well : from the Chalk. 420 Dr. B. Jones on the Passage of Crystalloids [1865. In ash direct. No lithium. In alcoholic extract. Very faint traces. No lithium. Entire sheep's kidney. One ounce of kidney. One ounce of mutton. ,, ,, One ounce of beef. „ „ It appears from these experiments that Potatoes showed lithium once in five trials. Apples ,, „ twice in four trials. Carrots „ no lithium in two trials. Bread „ lithium thrice in three trials. Cabbage „ „ twice in two trials. Tea ,, „ eight times in ten trials. Coffee „ „ four times in five trials. Port wine „ „ six times in six trials. Sherry „ ,, six times in six trials. French wine, „ four times in four trials. Rhine wine,, „ eight times in eight trials. Ale „ „ twice in three trials (traces). Porter „ „ twice in three trials (traces). Mutton, beef, and sheep's kidney showed no lithium : one kidney had a slight trace of lithium. I hope in a future paper, with the help of Dr. Dupre, to show that Thal- lium, Rubidium, and Caesium, by spectrum analysis, can be traced even into the crystalline lens, and to determine the rate at which they pass in, if not out of, the textures ; and by other means we shall endeavour to trace the passage of other crystalloids throughout the textures. CONCLUSIONS. 1. On the Rate of P assay e of Solutions of Lithium into the Textures of dnimals. In guinea-pigs, even in a quarter of an hour after three grains of chloride of lithium are taken into the stomach, the lithium may be found not only in all the vascular textures, but even in the cartilage of the hip- joint, and in the humours of the eye. If the same quantity is injected into the skin, in ten minutes it can be detected in the lens and everywhere ; and even in four minutes the lithium may be detected everywhere except in the lens. In half an hour after the same quantity is taken into the stomach, lithium may be found in the crystalline lens. After it has been taken eight hours, it may not have passed completely into the inner part of the lens. In twenty-six hours it will be found in every part of the lens. When half a grain only of chloride of lithium was taken, in less than 1865.] into and out of the Vascular and Non-vascular Textures. 421 four hours traces were found in the lens. And even when only a quarter of a grain was taken, faint traces of lithium were found in five and a half hours. 2. On the Rate of Passage of Solutions of Lithium out of the Textures of Animals. After two grains of chloride of lithium, in six days neither a young nor an old guinea-pig gave any lithium in the kidney, liver, or lenses. After two grains, in four days no lithium could be found in the lens, nor in the cartilage of a joint. After one grain, in three days the alcoholic extract of the lens showed no lithium. After a quarter of a grain of chloride of lithium, in sixteen days the minutest traces of lithium were detected in the liver, kidneys, and lens. After half a grain, for thirty-seven or thirty-eight days traces of lithium could be found in the urine. After three grains, traces were found in the lens for thirty-three days, and for thirty-nine days, the smallest quantity could be found in urine. The skin of guinea-pigs throws off lithium, and it collects on the hair and nails ; so that it is possible for the animal to redose itself with lithia from its own body, and thus to keep lithia passing in and out of the textures much longer than if a single dose only were taken. 3. On the Rate of Passage of Solutions of Lithium inland out of the Human Body. In ten-grain doses, lithium may be found in the urine in from five to ten minutes, and continue to pass out for six or seven days. In five-grain doses it may be in the urine in from ten to twenty minutes, and continue to pass out even for eight days. In twenty-grain doses, it may be found in small quantity in the crystal- line lens in two and a half hours, and be present in every particle of the lens in three and a half, five, and seven hours ; and no trace of lithium may be detectable in the lens after seven days, when twenty -grains of the carbo- nate of lithia had been taken. 4. Results of the examination of Solid and Liquid Food. Although almost every kind of vegetable food, and almost every fluid which we drink, contains infinitesimal quantities of lithia, yet. rarely, if ever, can lithium be detected iu any part of the body of man or animals, unless some larger quantity is taken than ordinarily occurs in the food or drink. APPENDIX.— Received July 8, 1865. On the Passage of Chloride of Rubidium into the Textures. A guinea-pig was given three grains of chloride of rubidium at 1 1 A.M. VOL. xiv. 2 I 42.2 Dr. B. Jones on the Passage of Crystalloids [1865. At 6.30 P.M it was killed. Rubidium was not detectable anywhere ; not even satisfactorily in the urine. Another guinea-pig was given ten grains of chloride of rubidium at 11.20A.M. At 3 P.M. scarcely any rubidium could be detected in the urine. The following day, at 1 1 A.M., it was given five grains more. At 2 P.M. rubidium was just detectable in the urine. The next day, at 2 P.M., it was again given five grains, the rubidium being just perceptible in the urine. Twenty-five hours afterwards it was killed. Extremely minute traces of rubidium were found in the kidney and in the blood ; somewhat more, but still very faint traces, in the liver. In the cartilages no rubidium could be found, nor in the aqueous humour of the eye. When the whole lens was incinerated at once the smallest possible trace of rubidium was found. The urine showed traces of rubidium. An elderly man took nineteen grains of chloride of rubidium four hours before he was operated on for cataract. The most careful search could not find any rubidium in the lens after its removal. Another patient, with a double cataract, was given twenty grains of chloride of rubidium. One lens was extracted ten hours afterwards, and the other seven days afterwards, but in neither could traces of rubidium be found. It was found by experiment that 1 6 ^ 0 0- of a grain of chloride of rubi- dium in water was detectable by the spectrum analysis. -^^Q of a grain in urine could be distinctly observed. On the Passage of Chloride of Caesium into the Textures. Delicacy of the reaction for Ccesium. — One grain of chloride of caesium in 400 cub. centims. of water just gives the blue caesium lines in a quantity of solution that can adhere to the loop of a platinum wire which took up 0'05 of solution. The * part of a grain of chloride of caesium in water can be detected. If potassium is present in the same solution the test is much less delicate. In urine, one grain of chloride of caesium in 200 cub. centims. is the limit of the reaction for a quantity remaining on the loop of the same wire as was previously used. Hence 62>1500 of a grain of chloride of caesium in urine can be detected. A guinea-pig was given three grains of chloride of caesium, and twenty hours afterwards another three grains. Twenty hours after the second quantity it waB killed. The ash of the urine showed caesium slightly. No caesium could be detected in the two lenses taken for one examination ; nor in the liquid humours of the eyes. A small portion of the ash of the kidneys and liver showed no caesium, but aqueous extracts, after con- centration, showed caesium' faintly. No caesium could be detected in the blood, nor in the bile. A guinea-pig was given six grains of chloride of caesium, and six grains more nineteen hours afterwards ; twenty-four hours after the second dose 1865.] into and out of the Vascular and Non-vascular Textures. 423 it was killed. No caesium could be found in the lenses, nerves, aqueous humour, blood, or bile. Urine, kidney, and liver showed caesium slightly in the aqueous extract of the ash. A guinea-pig was given ten grains of chloride of csesium, and twenty hours afterwards ten grains more. Twenty-seven hours after the second dose it was killed. The evaporated and incinerated extract of the two lenses showed the caesium only faintly. The aqueous humour of the eye showed caesium faintly. The evaporated and incinerated extract of the two large nerves of the legs showed caesium pretty distinctly. On the Passage of Sulphate of Thallium into the Textures. A rabbit was given one grain of sulphate of thallium. The urine, passed two hours after the first dose, gave the reaction very clearly. Another rabbit was given three grains of sulphate of thallium, and it was killed twenty-one hours and a half afterwards. This rabbit took no food after the dose of thallium, but the stomach was found completely full of dry food. Thallium was found in the kidneys, liver, and spleen,: by simply touching with a red-hot wire and bringing the small quantity of substance adhering to the wire into the flame. The blood, lens, and cartilage showed none in this manner. The aqueous extract, however, of the coagulated blood and lens showed thallium distinctly. The cartilage of the hip could not be thus examined, owing to the small quantity to be got. Another rabbit was given three grains of sulphate of thallium, and it was killed in six hours and a half. The aqueous extract of the lens showed thallium distinctly. A guinea-pig was given two grains of sulphate of thallium, and twenty hours afterwards it took two grains more ; twenty-two hours after the second dose it was killed. The urine showed thallium only after con- centration. Small pieces of the liver, kidney, cartilage of the short ribs, and large nerve of the leg showed thallium distinctly. Humours of the eye showed thallium distinctly. Aqueous extract of the lenses to- gether showed it distinctly. The blood showed no thallium directly, but the aqueous extract of a small quantity of coagulated blood showed the thallium very faintly. The brain showed the thallium also very faintly. The toe-nails showed the thallium very distinctly ; and the hair of the belly also showed it very distinctly. Another guinea-pig was given two grains of sulphate of thallium, and it was killed in six hours. The aqueous extract of the lens showed thallium faintly. The urine showed the thallium distinctly. The aqueous extract of the two large nerves showed no thallium. On the Passage of Sulphate of Silver into the Textures. A guinea-pig was given one-eighth of a grain of sulphate of silver. Twenty-three hours afterwards it was given another eighth of a grain. 424 Dr. B. Jones on the Passage of Crystalloids, $c. [1865. Twenty-seven hours afterwards a third eighth of a grain was given ; and the same dose on the third, fourth, fifth, sixth, seventh, ninth, and tenth days ; on the eleventh day the animal died. One grain and a quarter of sul- phate of silver in twelve days was taken. The ashes of the liver, kidney, and stomach showed silver fairly, by means of galvanic precipitation of silver or copper. The ash of the bile showed silver rather less distinctly. The ash of the urine showed the silver only very slightly. The ash of the lenses showed only very slight traces of silver, and the ash of the brain showed none. On the Passage of Chloride of Strontium into the Textures. Two guinea-pigs, which had been given no strontium, had the whole kidney, liver, and lenses examined for strontium, but no trace of it could be found. A guinea-pig was given four grains of chloride of strontium ; in seven hours it was killed. The urine showed strontium distinctly in a single drop. No strontium could be detected in the kidney, liver, or lens, though a whole lens was taken for the examination by the spectrum analysis. Another guinea-pig was given ten grains of chloride of strontium ; in fourteen hours and a half it was killed. A small quantity of urine showed no strontium, and no strontium was found in the ashes of the kidney or liver. To a third guinea-pig half a grain of chloride of strontium was given. Nineteen hours afterwards the urine showed traces of strontium, and then half a grain more was given. Twenty-four hours and a half afterwards another grain was given ; and twenty- four hours after this half a grain more. Twenty-seven hours afterwards another half grain of chloride of strontium was given. At this time then the urine showed strontium very distinctly. On the sixth day another half grain, and again on the seventh, eighth, ninth, tenth, and eleventh day, until five grains and a half were taken. The twelfth day it was killed. The urine showed strontium dis- tinctly. No strontium could be detected in the lens, humours, or blood ; and minute traces only in the ash of the kidneys and liver. Proc-Roj. Soc- Vol . XF. Plat* VH. Pmc.Say.Soc. VdJfltfHateEL 1865.] Pendulum Base Observations for India. 425 " An Account of the Base Observations made at the Kew Observa- tory with the Pendulums to be used in the Indian Trigonome- trical Survey." By BALFOUR STEWART, M.A., LLJX, F.R.S., Superintendent of the Kew Observatory, and BENJAMIN LOEWY, Esq. Received June 13, read June 15, 1865. Her Majesty's Indian Government, on the recommendation of the Royal Society, lately decided that pendulum observations shall be made at different stations in India in connexion with the Great Trigonometrical Survey of that country. The object of these proposed observations may be stated in a very few words. The labours of those engaged in the Trigonometrical Survey have already disclosed the fact that the direction of the plumb-line in the north- ern stations of India was influenced to some extent by the mass of the Himalayas, and it was therefore thought highly desirable that the influ- ence of these mountains upon the intensity of terrestrial gravity should be investigated in addition to their influence upon its direction. The propriety of this view will at once be evident, if we reflect that by knowing the change produced not only upon the direction of gravity, but also on its intensity, we know at once all the particulars of the disturbing mountain- force both as regards magnitude and direction. It was therefore with the view of ascertaining the alteration which these mountains might cause upon the intensity of gravity that the Indian pen- dulum observations were decided upon. In consequence of this decision, Captain Basevi, R.E., and first assistant in the Survey department, was ap- pointed to superintend the observations, and instructed to repair to the Kew Observatory previously to his departure for India, in order to become acquainted with the necessary instruments, their adjustment, and the method of observing with them. After attending daily at the Observatory from the beginning of Septem- ber to the middle of November, this officer was perfectly instructed in every particular necessary for the practical part of these observations, as well as for their calculation and reduction. He was then obliged to leave for India, being prevented by his early departure from making the necessary base determinations with the instruments at Kew Observatory. The best arrangement of apparatus formed the subject of careful discus- sion with Colonel Walker, Superintendent of the Indian Survey ; and the experimental arrangements ultimately adopted received the sanction of this officer, who, besides suggesting several improvements, made himself tho- roughly acquainted with all the details of the apparatus. VOL. XII. 2 K 426 Pendulum Base Observations for India. [1865. A room suitable for these observations was constructed in the south-east corner of the Observatory, the expenses of which were defrayed from the Government Grant Fund of the Royal Society. The following simple diagram will be sufficient to show the experimental arrangement in the Pendulum-room. C is the place for the clock, which is connected with the transit-instrument; P is the pillar bearing a slab attached also to the wall at W, to which the receiver (E) is rigidly fixed. T is the telescope for the observations of the coincidences, mounted on a pillar which stands in a depression, so that the observer is not under the necessity of kneeling down during the observation. In every other part the arrangement is entirely similar to that de- scribed by General Sabine in the Philosophical Transactions for 1829, — with this difference, that the receiver was in our experiments a copper one with glass windows. The whole of the apparatus was made by Mr. P. Adie, who deserves the highest praise for the excellent manner in which the work was executed by him. The pendulums used were those marked No. 1821 and No. 4, used formerly by General Sabine in different parts of the globe. The former was also used by Mr. Airy in his Harton experiments. Method of registering and reducing the Observations. The manner in which the number of vibrations, made by a detached pendulum, are determined from a series of observed coincidences with the pendulum of a clock has been so often described, that we may refer to the writings of Kater, Sabine, Baily, and others on the subject. The esta- blished methods have been followed throughout in these experiments, and 1865.] Pendulum Base Observations for India. 427 the only change introduced was a very slight one, with the view of obtaining a more correct arc of vibration. It is usual to observe the arc a little after the coincidence, which does not give the true arc corresponding to it. To obviate this, the arc was read in our series about 30 seconds before, and again 30 seconds after each observed coincidence, marking first the right edge of the tailpiece and then the left one. If we call these four readings of the scale a, b, c, d, we may consider as a very exact representation of the reading for the arc at the instant of the coincidence. The adjustment of the diaphragm, disk, and tailpiece was made very carefully at the commencement of the experiments. Nevertheless it was found slightly deranged when the pendulum was reversed. In this case, as is well known, the disappearance and reappearance of the disk are not each instantaneous ; but we see first one side of the disk, then the other disappear, and in the same order reappear, so that we have four events, of which, calling the time of their happening respectively a, /3, y, c>, either )> lastly> r will give us the time of coincidence. In a few sets of our series the first formula was used ; but it was soon found that the correct registration in such a case is a matter of the greatest difficulty, and it was therefore thought in one instance preferable to stop the clock and repeat the adjustment, and afterwards a similar derangement was rectified by a lateral motion of the observing telescope. With a few trials, using a few successive coincidences for the purpose, it is quite possible to adjust the whole to the greatest nicety without stopping the clock. The reduction of the observations was made entirely after the manner of former experimenters. It comprises the following corrections : — A. Correction of the observed arc-readings and reduction of the vibra- tions to infinitely small arcs. In the first place, the scale for reading the arc being behind the tailpiece of the pendulum, the registered readings are too large. Let D be the distance of the scale from the object glass of the telescope, d its distance from the tail of the pendulum, O the observed reading of the whole arc on the scale graduated from end to end, S the distance of the indicating- point of the tailpiece from the knife-edge, then the true arc, or more correctly semiarc observed (=a), through which the pendulum moved from the vertical, is given by the formula expressing all distances in inches, into which the scale was divided. 2 K2 428 Pendulum Base Observations for India. [1865. The values of t ~- were determined for each pendulum from accurate measurements, and are 9874 For pendulum No. 4 in position, face on =- face off = „ „ No. 1821 „ face on = face off = 2 X 100-22 x 49-89 99-67 2x100-22x49-89 99-47 2x100-22x49-3 98-95 2x100-22x49-3 The logarithms of these expressions were added to those of the observed readings for the logarithm of the tangent of a. In the next place, the reduction to infinitely small arcs was deduced from the well-known formula, Number of infinitely small vibrations =n + n x M S'" (a + a>) sm (*."*? *, 32 (log sm a — log sin «) where M denotes the logarithmic modulus =0-4342945 ; * the initial, and «' the final semiarc of vibration, expressed in degrees, minutes, and seconds, n being the number of observed vibrations ; and to obtain a more correct result from this formula, the calculation was made/or each interval between two successive observations. B. The rate of the clock was determined from a series of observations of star-transits, the results of which are given in Table I. The rate was somewhat unequal during the experiments, the range being equal to T%ths of a second ; and besides, the unfavourable state of the weather occasioned longer intervals between the observations than was desirable. To free the results as far as possible from any errors arising from this source, the rates were represented in a series, as shown in Table II., which also gives the actual number of vibrations made by the sidereal clock in a mean solar day, as deduced from the following formula : — Number of vibrations in a mean solar day =Nr=86636-5554( 1 — r \ \ b0400/ where r is the observed rate, which in our case was a losing one throughout the whole of the observations. If we now call V the number of observed vibrations of the clock -pen- dulum from beginning to the end of one experiment, V the number of observed vibrations of the detached pendulum during the same time, cor- rected for the amplitude of the arc, and finally N' the number of actual vibrations of the clock in a mean solar day at the date of the experiment, found as above, we have for the number of infinitely small vibrations of * See Memoirs of the Royal Astronomical Society, yol. vii. p. 22. 1865.] Pendulum Base Observations for India. 429 the detached pendulum during a mean solar day the following pro- portion : V : V : : N' : N, XT VN' N=-T?T-« TABLE I. — List of Transits observed in connexion with the Pendulum Experiments for India, and clock-rates deduced from them. Date. Name of Star. Eight Ascension. Time of passing mean wire. SutnoJ instru- mental errors. Error of clock. Mean rate deduced. 1865. January 7. » 8. „ 9. „ 13. „ 14. „ 16. ,, 17. » 19- „ 20. ,, 22. /3 Arietis a. Arietis PCeti aPersei i] Tauri h m s i 47 12-40 i 59 35-42 2 2O 60-28 3 H 44'47 3 39 29-68 3 5i 4514 4 28 12-58 13 48 15-68 14 9 30-38 14 26 0-57 14 39 5-z6 13 48 15-71 14 9 30-42 14 26 o-6i H 39 5'3° H 9 3°'54 J4 39 5'43 '4 39 5H6 '4 43 25-37 i 34 25-30 i 47 12-31 i 59 35'33 2 21 O'2O 3 39 29-61 14 26 0-85 H 39 5-52 14 43 25-43 14 9 30-67 14 26 0-89 H 39 5'55 14 43 25-46 3 39 29-55 4 20 46-05 4 28 i z'49 3 14 44-22 3 61 45-20 4 20 46-04 4 28 12-48 5 6 46-01 3 H 44-i8 3 39 29-52 3 51 45-18 4 20 46-02 4 28 12-46' h m s i 47 7-96 i 59 30-96 2 20 55-42 3 14 40-84 3 39 25"i6 3 51 40-06 4 29 39'4 13 48 9-98 14 9 24-72 14 25 55-16 14 38 59-68 13 48 8-4 14 9 22-98 14 24 53-74 14 38 58-2 14 9 i6'i 14 38 51-02 14 37 4-56 14 41 23-70 i 32 23-44 i 45 10-66 i 57 33-8 2 18 58-28 3 37 27-98 14 23 56-72 14 37 1-16 14 41 20-18 14 9 45-86 14 26 16-3 14 39 2i'o 14 43 40-22 3 39 4I-°6 4 20 57-54 4 28 23-78 3 14 54-92 3 5i 54'i6 4 20 55-6 4 28 21-94 5 6 56-2 3 H 51-28 3 39 3574 3 51 50*66 4 20 52-16 4 28 18-38 +oS76 +0-70 + 1-03' -0-17 -f-o-68 + 1-48 +0-85 + 1-06 + 1-04 +0-81 + 0-89 +0-84 +0-82 +°'55 +0-64 4-0-97 +0-81 -j-o-88 + 1-65 4-i-iz +0-79 +°73 -f i -06 +0-71 +0-79 +0-87 + 1-65 + 1-13 +0-92 +0-98 4- 1 '69 +°"57 +0-69 +0-76 -°'33 + 1-4! 4-o-Si 4-0-83 — 0-03 -0-17 4-0-67 4-1-46 4-0-88 +°'94 m s - 3-68 - 376 - 3-83 - 3-8o - 3-84 - 3-82 - 3-85 - 4-64 — 4*62 — 4-60 — 4'69 - 6-47 - 6-62 - 6-32 - 6-46 - I3-47 — 1 3 '60 — 2 O"O2 — 2 O'O2 -2 074 -z 0-86 — 2 0'8o 2 0-86 s -1-81 -1-83 -1-76 -1-64 1-76 /Eridani a Tauri « Bootis p Bootis eBootis tj Bootis a. Bootis p Bootis eBootis « Bootis eBootis eBootis «2 Libra v Piscium /3 Arietis a Arietis g2Ceti yTauri p Bootis e Bootis — 2 0*92 -2 3"34 -2 3'49 — z 3'6o 4- i6'3z 4- 16-33 4- 16-43 + 16-45 4- 2-08 + 2-18 4- 2-05 + o'39 + °"37 + 0-37 + 10-29 4- 10-16 + 6-93 4- 6-89 + 6-94 + 7'°2 + 6-86 a2Libra3 aBootis -1-67 -1-77 -1-71 p Bootis eBootis «2Libra TjTauri eTauri «Tauri «Persei 7' Eridani eTauri aTauri aAurigse aPersei 7/Tauri y' Eridani eTauri aTauri 430 Pendulum Base Observations for India. TABLE I. (continued.') [1865. Date. Name of Star. Eight Ascension. Time of passing mean wire. Sum of instru- mental errors. Error of clock. Mean rate deduced. 1865. h m s h m s s m s January28. /3Tauri 5 17 47-76 5 17 46'36 +0-96 - 0-44 d Orionis 5 25 8-50 5 25 6'5 + r42 - 0-58 e Orionis 5 29 23-66 5 29 21-721+1-44 — 0-50 s a Orionis 5 47 53-8o 5 47 51-96+i'3i - 0-53 — 1-22 Febr. 9. y'Eridani 3 Si 44'9° 3 5i 29-06 + 1-53 -I4-31 eTauri 4 20 45-78 42,0 7o*c8 +o'8i — 14-39 «Tauri 4 2g 12-23 *"* J J° 4 27 56'98 +0-87 -14-38 i Aurigae 4 48 I4-34 4 47 59'3 +0-63 - I4'4 * e Leporis 4 59 46-14 4 59 30-06 + i'79 — 14-29 aAurigse 5 6 45-68 5 6 31-16 + O"22 — 14-30 /3Tauri 5 17 47'6i 5 17 32-26 +0-88 -14-47 « Leporis 5 26 48-22 5 26 31-96 + I-73 -H'53 -ri6 ., 17 t Auriga 4 48 14-29 4 47 48-36 +0-41 -25^2 e Leporis 4 59 45'99 4 59 18-68 + i'73 -25-58 « Aurigae 5 6 45-52 5 6 19-98 — 0-06 — 25-60 /STauri 5 i? 4747 5 17 21-36 +0-54 -25'57 S Orionis 5 25 8-24 5 24 41-4 + 1-22 -25-62 -1-40 „ 19 /i Geminorum . 6 14 49-62 6 14 20*16 4-0-50 — 28-98 y G-eminorum . 6 29 56-79 6 29 27-08 +0-66 -29-05 a. Canis Majoris 6 39 13-88 6 38 43-26 + 1-50 — 29'12 -1-69 ,, 20 t Aurigae .... 4 48 14-13 4 47 42-58 4-0-82 -3°'73 e Leporis 4 59 45^3 4 59 '3-4 + 1-84 -30-69 K. Aurigae 5 6 45'43 5 6 14-26 +0-45 -30-72 jSTauri 5 17 47-42 5 *7 J5'7 4-0-92 -20-80 a Leporis .... 5 26 48-03 5 26 15-48 4-175 — 30-80 -1-80 TABLE II. — Showing the rate of the clock, and the number of its vibra- tions during a mean solar day. No. f exp. Eate (sid. time). So. of vibr. in a mean solar day =N'. No. of exp. Eate (sid. time). $o. of vibr. in a mean solar day =N'. No. of exp. Eate (sid. time). No. of vibr. in a mean solar day =N'. s s i -1-76 86634-795 21 - -16 86635-395 41 -1-40 86635-155 2 -1-76 86634-795 22 - -16 86635-395 44 -1-40 86635-155 3 -1-76 86634-795 23 - -16 86635-395 43 -1-46 86635-095 4 -1-76 86634-795 24 - -16 86635-395 44 -1-52 86635-035 5 -1-64 86634-915 5 - -16 86635-395 -1-52 86635-035 6 — 1*64 86634-915 6 - -16 86635-395 46 -1-58 86634-975 7 ' -1-64 86634-915 7 - -16 86635-395 47 -1-58 86634-975 8 -1-76 86634-795 8 - -16 86635-395 48 — 1-64 86634-915 9 -1-76 86634-795 9 - -16 86635-395 49 -r64 86634-915 10 -1-67 86634-885 3° - -16 86635-395 5° -1-64 86634-915 ii -1-67 86634-885 - -16 86635-395 -1-64 86634-915 12 -1-77 86634-785 32 - -16 86635-395 S2 — 1-69 86634-865 J3 -i'73 86634-825 33 - -16 86635-395 53 — 1-69 86634-865 14 -1-69 86634-865 34 - -16 86635-395 54 -1-69 86634-865 15 -1-26 86635-295 35 — '22 86635-335 55 — 1-69 86634-865 16 — 1-24 86635-315 36 — "2.1. 86635-335 56 -1-69 86634-865 17 — 1-22 86635-335 37 - -28 86635-275 57 -J75 86634-805 18 — 1-20 86635-355 38 -1-28 86635-275 58 -175 86634-805 19 20 -1-18 -1-18 86635-375 86635-375 39 40 -1-28 -I'34 86635-275 86635-215 g 86634-805 86634-805 1865.] Pendulum Base Observations for India. 431 C. Correction for temperature. — Two thermometers were fixed, one to the lower, the other to the upper part of a brass bar, which was made by Mr. Adie, of precisely the same form as the pendulums. The brass bar being fixed near the middle of the receiver, close to the swinging pendulum, every, change in the temperature of the latter was of course shared by the brass bar, and indicated by the two thermometers, which were extremely sensitive and read to '05 of a degree. The readings of these two thermometers were in the first instance corrected for index- error. The instruments having been very carefully compared with the Kew Standard, a table of index-errors was made from these comparisons, and, by interpolation, giving the errors from degree to degree. Another correction was applied for the observations in the exhausted receiver on account of the eifect of exhaustion on the glass tubes of the thermometers. This effect was determined very accurately by a series of experiments at Kew, and found to be equal for both thermometers, and amounting to 0°'43 for a decrease in pressure of 29'210 inches. This correction is smaller than that assumed by General Sabine and the late Mr. Baily, who make it | of a degree for the thermometers which they employed. Our experiments showed the remarkable fact that the correction is by no means proportional to the decrease in pressure. The diminution of the pres- sure from 30-080 inches to 13-610, that is, by an amount of 16-470 inches, gave a correction of only 00<0/>2, while a further decrease of 12-820, bringing the pressure to 0790 inch, gave for one thermometer 0°'377, and for the other 0°-385. The mean of the upper and lower thermometer reading will give the temperature of the pendulum at the moment of the observations ; and if we call t, t', t", t'" the temperatures found in this manner for the successive observations, we have t_ + t_ t' + t" t" + t'" 2 ' ~~2~' 2 as the most probable temperature during the interval between two con- secutive observations. These intervals being of unequal length, we will call n, ri , ri', ri", the number of coincidence-intervals which they contain ; and calling t° the mean temperature of the whole experiment, we have n-\-ri Table III. gives the mean temperature found in this manner for each ex- periment, and shows the mean of all observed temperatures for each pendu- lum, to which temperature all the experiments made with that pendulum have been reduced. For this reduction it would have been best if we had had an opportunity of swinging the pendulums at extremes of temperature, say about 50° distant from each other. But the desirability of sending the appa- ratus to India under the care of Mr, Hennessey, who left by the March mail, 432 Pendulum Base Observations for India. [1865. prevented such a course, and we availed ourselves of the elaborate series of experiments on the temperature corrections of pendulums, made by General Sabine (vide Phil. Trans. 1830, p. 251), which gives 0'44 vibration per diem for each degree of Fahrenheit's scale. General Sabine found in a former series this correction nearer to 0'43 ; and he says, in the above men- tioned publication, " The probable error which may be incurred by employ- ing the correction 0'44 for each degree as now determined, can only be very inconsiderable ; but when the differences of temperature amount to 50°, which is a case of actual experience in pendulum observations, the question of whether 0'43 or 0'44, for example, be the more correct value, involves an uncertainty in the ultimate result of no less than half a vibration a day." The pendulums which we used were not those employed by General Sabine in his determinations, but they were made by the same maker at the same time, and very probably from the same kind of brass, and there cannot be the least doubt that the true correction will lie between 0-43 and 0'44. We have therefore adopted 0'435 for our reductions ; and as the greatest difference in temperature between a single experiment and the mean is less than 11°, the greatest error would in this case amount only to y^-yths of a vibration per diem, an error too small to affect seriously the mean result of the whole. At the same time we must state that, as Colonel Walker and Captain Basevi inform us, experiments will be made in India with both pendulums, to ascertain their exact constants with regard to expansion, and that our results will of course have then to be modified accordingly. 1865.] Pendulum Base Observations for India. 433 TABLE III. — Showing the Mean Temperature for each experiment, and the Mean of the whole series for each Pendulum. Pendulum No. 1821. Pendulum No. 4. No. of Mean tem- No. of Mean tem- experiment. perature. experiment. perature. o o i 57-963 I 55-869 2 54'573 2 52-692 3 53750 3 52-116 4 54-460 4 53-586 5 52-890 5 54-269 6 52-300 6 5''°47 7 5^233 7 51-432 8 53'339 8 52-093 9 53'397 9 53'972 10 49' i 54 10 50-794 ii 49'°75 ii 45-631 12 51-649 12 50-120 13 49-789 *3 50-455 14 5°795 14 57-081 IS 477^3 15 56-737 16 48-813 16 58-894 *7 48-398 17 59-412 18 48-843 18 60-954 *9 48-203 '9 6o-597 20 46-264 20 62-560 21 46-515 21 65-55I 22 50-892 22 59-162 ^3 50-077 23 61-489 24 50-352 24 62-183 25 54-051 25 64-151 26 55'7H 26 66-690 27 55'536 28 56-561 29 58-344 Mean .... 51-781 Mean .... 56'520 "D. Correction for pressure of air. — This correction, as shown in the Phil. Trans, for 1832, is thus determined : — Let ft' denote the reading of the gauge for the mean of the experiments made in air, and ft" the same reading for the mean of the vacuum experi- ments ; also let t° denote the mean temperature of all the experiments, both in air and vacuo, then the expression ft'-ft" — 32) will denote very nearly the mean difference of density between the two sets of experiments. Now if N' denote the mean number of vibrations in air during a mean solar day, and N" the mean number of vibrations in vacuo during the same time, then the constant for one inch of reduced pressure will be •flit _ "Vrr C'=pr^r(l + -0023(^-32)). Hence if ft denote the actual mean pressure for a single experiment and 434 Pendulum Base Observations for India. [1865. t the mean temperature of that particular experiment, the final correction for that experiment will then be found C =C' v /3 I + '0023(*-32)' The following Table (IV.) gives the elements for obtaining the constant C' for both pendulums. TABLE IV. — Elements for deducing the Constant C' from the Experiments in Air and in the Exhausted Receiver. Pendulum No. 1821, Position " Face on." In Air. In the Exhausted Eeceiver. No. of experi- riment. Number of corrected vibrations. Pressure. Tempe- rature. No. of experi- ment. Number of corrected vibrations. Pressure. Tempe- rature. in. in. I. 86063-840 29-793 57-96 I. 86072-053 2-165 49-I5 II. 86063-881 29-381 54'57 II. 86072-725 1-3^5 49-07 III. 86063-818 29-193 5375 III. 86072-643 1-402 51-65 rv. 86064-126 29-153 54-46 IV. 86072*917 0-943 49-79 V. 86063-771 29-048 54-°5 V. 86072-846 1-944 50-80 VI. 86064-240 29-103 55'7* VI. 86072-495 0-905 47'72 VII. 86064-202 29-222 55-54 VIII. 86064-138 29-271 56'56 IX. 86064-015 29-362 58-34 Means... 86064-015 29-281 55-66 Means... 86072-613 1-447 49-70 Pendulum No. 1821, Position "Face off." in. in. I. 86064-362 28-906 52-89 I. 86073-049 0-781 48-81 II. 86064-206 28-718 52-30 II. 86072-769 1-461 48-40 III. 86064-354 28-990 52-23 III. 86072-349 1-031 48-84 IV. V. 86064-578 86064-423 29-180 29-068 53-34 53-40 IV. V. 86072-385 86072-200 0-814 0-960 48-20 46-26 VI. 86063-433 29-378 50-89 VI. 86072-289 i-5i3 46-51 VII. 86063-375 29-279 50-08 VIII. 86062-738 29-005 5°'35 Means... 86063-934 29-065 5I-94 Means... 86072-507 1-093 47-84 Pendulum No. 4, Position "Face on." in. 1 in. o I. 86162-815 29-926 55-87 I. 86171-544 1-649 57-08 II. 86162-495 3o'i59 52-69 II. 86171-213 1-831 56-74 III. 86162-518 30-427 52-12 III. 86170-853 2-865 58-89 IV. 86162-351 3°"459 53'59 IV. 86170-518 3-340 59'4! V. 86162-394 30-532 54-27 V. 86170-909 3-839 60-95 VI. 86162-774 29-718 60-60 VII. 86163-228 29-709 62-56 VIII. 86163-337 29-683 65-55 Means... 86162-739 30-077 57-16 Means... 86171-007 2-705 58-61 1865.] Pendulum Base Observations for India. TABLE IV. (continued.) 435 Pendulum No. 4, Position " Face off." In Air. In the Exhausted Eeceiver. No. of experi- ment. Number of corrected •vibrations. Pressure. Tempe- rature. No. of experi- ment. Number of corrected vibrations. Pressure. Tempe- rature. in. in. I. 86162-460 30-631 5i'°5 I. 86172-510 1-491 50-79 II. 86162-187 30-638 5r43 II. 86171-026 1-973 4775 III. 86162-994 30-640 52-09 III. 86172-383 °'575 45-63 IV. 86162-933 29-355 59-16 IV. 86172-236 0-637 50-12 V. 86163-613 29-303 61-49 V. 86171-482 °'53S 5°"45 VI. 86163-484 29-306 62-18 VII. 86163-480 29-477 64-15 VIII. 86163-757 29-647 66-69 Means... 86163-113 29-874 58-53 Means... 86171-927 1*042 48-95 Determination of the Constant Cf from the above Mean Results. N"-N'. 0'-/3" I + -0023(^-32). Value of C'. Pendulum No. 1821, Face on... „ Face off... Pendulum No. 4, Face on „ „ „ Face off 8-609 S'573 8-268 8-814 27-834 27-972 27-372 28-832 1-047564 1-041147 1-059524 I-O5OOO2 0*324010 0-319096 0-320040 0-320988 E. The reduction of the resulting number of vibrations to the sea-level is calculated from where E is the earth's radius at the latitude of the Kew Observatory, h the height of the receiver above the mean level of the sea, and x a quantity which, with Dr. Young, may be assumed for a tract of level country to be = •666 (vide Phil. Trans, for 1819, page 98). This correction has been only applied to the ultimate mean number of vibrations of each pendulum. Taking Bessel's value for the semiaxis major and the eccentricity of the earth, andh=l7'5 feet as given by measurement and the known height of our standard barometer, the logarithm of the factor for this correction is 7-7467623. Result. Adopting the values for the reduction to a vacuum as found in Table IV., and applying the correction to those experiments, which were made in a highly rarefied medium, we find the following numbers of vibrations made by each pendulum in both positions in a mean solar day in vacuo, viz. for 436 Pendulum Base Observations for India. [1865. Pendulum No. 1821, Face on, Exp. I. 86072-728^ II. 86073-138 ' III. 86073-078 I ofin-TA^ IV. 86073-211 >860'3-°64 V. 86073-450 VI. 86072-777 Face off, Exp. I. 86073-289^ III. 86072-668 I 8fiM7o fi44 IV. 86072-635 >86072 844 V. 86072-497 VI. 86072-756J Pendulum No. 4, Face on, Exp. I. 86172-043) II. 86171-767 Mean: III. 86171-717 V86171-822 IV. 86171-524 V. 86072-061J „ Face off, Exp. 1.86172-969^ II. 86171-637 I Mean: III. 86172-562 V86172-249 IV. 86172-432 V. 86171-647J And reducing the means to the sea-level, we obtain the following Final Result : — Pendulum No. 1821, Face on, 86073-112 vibrations in a mean solar day. „ „ Face off, 86072-892 Pendulum No. 4, Face on, 86171*870 „ „ „ Face off, 86172-297 >, Finally, we give an example of one experiment, with the mode of its reduction. 1865.] Pendulum Base Observations for India. 437 O 1 ° 3 O 2 a £ oo "ioo d m pi in d O . r~- t^oo oo t-^t^oo o\ o\ .go cb b '-> « M « « . | | O 71 « ON <3N O rj- M O p « H 1 3 ^^^^^,0 ^^^ 1 i^iOOOO^o Ov^vOOm1^ 11 rt co N « r» c?vvo -4- M rt co o mm tn m vn Vo 'o b\ ON b b b H p ^- 1 t> TJ-COO^OVOTj- rJ-COMQ O\00 dHc4ONO>O\ W-)lOW-»^-COCO ci 'd V» M M M b b b b b b •3 •*» co en M O O C7\ O ooo ro r» N wi ui 10 ^- ^- ro t-^vo vo vO vo « *J cococncococo dc4dddr) jP 1 «j M H W H M M M '(•> Cl CJ r) C-l -a' I « vOMrlOOOOt^ VOU-.HWP-IO MMclOsOC7> uiinu-,^-,}.^- c> c> c> « M M b b b b b b 1 *ti vo^ri-NcJM i-iOo^^co oooooot-^t^t^ OOC^o^oo^ U 1 000000 " «« 8 »o 10 in >« u-, ir> cnuoovow^ 0 § 11 s| «r^^-rlvOroO roO^J-OOOvO fl vo d t^oo coos vOvot^-O^nO •a , ] vi 10 vr, to 10 xy, vr, w, w-, u-> un u-> 11 I mooincor~,Tj->-i r^mo\>OTj-M VO 1-1-^-10 M^«tJ-U-> 'S S1* j y^^^^^^ ^ ^ r :° ^ .•« ij S| I g vO r» r>-oo coo\ \ovot--O>^>>-i WWCICOCO 1HCO^«1-10 "§*' 8 S M^ « j 1 x vb ro w in 'd OS b\ >noo in *M b co HirJ-inm wco co^ui »o «n in ui vn ws in m m m «n m it! S^ ' eji 1 1 oovOco>iindOs Os inoo vn N O co w^-mvn wco co^j-m fi vo d r~.oo cooo vo vo t^ O m O i-it-tdcoco Mro^J-^'in rfl N ^ i^ JT £* o III j «dcot^ooos comosco^J-m M HI M m 'n tnoo oo oo rS4 g 1 438 Pendulum Base Observations for India. Preliminary corrections. [1865. Correction of the Thermometer- Eeadings. Computation of semiarc of vibration =«. Corrected for index error. Corrected for effect of ex- haustion. Mean reading of scale = O. Logarithm ofO. Logarithm of tan «. True semiarc = «. Upper. Lower. Mean. 53-I7 53-22 53'32 53-22 5*755 52-805 52-905 5i'655 52-962 53-012 53-112 5*'937 53-392 53-442 53'542 53-367 2-250 2-225 2'2IO 1-970 0-3521825 0-3473300 0-3443923 0-2944662 8-3550433 8-3501908 8-3472531 8-2973270 17 51 16 59 16 28 8 10 53-22 53*7 49-92 49-67 52-655 52-705 49-21 49-01 52-937 52-987 49-565 49-340 53-367 53-4I7 49-995 49-770 I-970 ^955 0-550 0-540 0-2944662 0-2911468 9-7403627 9-7323938 8-2973270 8-2940076 7-7432235 7-7352546 8 10 7 39 19 2 iS 41 49'43 50-22 50-27 50*37 48-81 49-74 49-84 49-94 49-120 49-980 50-055 50-I55 49-550 50-410 50-485 50-585 0-515 0-505 0*400 0-390 9-7118072 9-6074550 9-6020600 9-5910646 7-7146680 7-6103158 7-6049208 7-5939254 *7 49 14 i 13 5i 13 30 Correction for amplitude of arc and rate. Number of Coin- Vibra- tions of clock Vibra- tions of detached log. M sin (*+«') sin («-*') lQgw + Correction for ampli- infinitely small vibrations cidence. pen- dulum. pen- pulum =n. 32 (log sin a. —log sin «') = logA. kgA. tude, during experi- ment. per diem. i to 2 307-0 305-0 5-5009216 7-9852214 0*0096654 2 — 3 308-0 306-0 5-4931423 7-9788637 0-0095250 3 — 17 4294-0 4266-0 5-4412666 9-0712875 0-1178386 17 — 18 18 — 19 i- 614-0 6 10*0 5-3871234 8-1724532 0-0148749 f 8 19 — 153 41243-0 40975*0 4-9438104 9-5563294 0-3600223 • Jo £ '53 — 155 617-0 613-0 4-2743172 7-0617777 0-0011529 1 i55 — 159 1233-5 1225-5 4-2457725. 7-3340858 0-0021582 vg 00 159 — 183 7406-5 7358'5 4-1249578 7-9917471 0-0098118 183 — 184 308-0 306-0 4-0114300 6-4971514 0-0003142 184 - 185 308-0 306*0 3-995I628 6-4808842 0-0003026 j , 56639-0 56271-0 0-5256659 1865.] Pendulum Base Observations for India. Correction for temperature. 439 Tempera- £-« Number ' ture of Is g 1 of Coin- cidence. pendulum during interval Number of intervals. v(t+t\ n(T2~) II vibrations per diem corrected t+f II & a* for tempe- "T- 3*8 II rature. 1 tO 2 53*417 53-417 a — 3 53*492 i 53'492 3—1? 54'454 H 762-356 §" 17 — 18 / 53-367 i 53'367 •43 18 — 19 19 — 153 153 — 155 L53'392 51-706 49-882 i 134 2 53'392 6928-604 99764 o\ •V? 0 1 86072-643 V-l iSS — 159 49-660 4 198-640 p O 159 - 183 49-980 24 1199-520 1 183 - 184 50-447 i 50-447 184 — 185 50-535 i 50-535 . 184. 9503'534 Correction for pressure of air. Mean pressure in the receiver during the experiment = 1-402 inch=/3. Mean temperature in the receiver during the experiment= 5i°-65 = £. £—32 = 19-65 log= 1-2933626 Iog/3=o'i46748o log -0023 =7-3617278 log 0 = 9-5105577 9'6573057 •0023 X(^— 32) = 0-045 J95 log= 8-6550904 log I-j-'OO23(£- Correction for pressure =0-43 5 ^=9-6381084 EESULT OP THE EXPERIMENT. Corrected vibrations : 86072-643 + 0-43 5 for pressure of air. Number of vibrations in vacuo : 86073-078 440 Dr. Davy on the Temperature, %c., of Birds. [1865. " Some Observations on Birds, chiefly relating to their Temperature, with Supplementary additions on their Bones." By JOHN DAVY, M.D., F.R.S., &c. Received May 26, 1865 *. The observations which I have now the honour to submit to the Royal Society, have been made with the hope of contributing something to the elucidation of the high temperature for which birds as a class are remark- able. I. Of the Temperature of the Common Fowl (Gallus domesticus). Mr. Hunter, in his paper entitled " Of the Heat, &c. of Animals and Vegetables," published in the Philosophical Transactions for 1778, states that he found the temperature of the common fowl, both male and female, in the intestinum rectum between 103° and 104° of Fahr. From such ob- servations as I have made, both in Ceylon and in England, it would appear that the temperature of this bird is considerably higher. In the former I found it as high in recto as 110° and 1 1 1°, and this in December, when the average temperature of the atmosphere, in that part of the island where the trials were made, is about 77°, which was the temperature of the air at the very time. In the latter I have found it to vary from 107° to 109° *. That the temperature of the common fowl should be a little lower in England than in Ceylon, is no more than might be expected, from the analogy of the difference of temperature of man in the two climates ; and, in accord- ance, in the fowl I have found that even in England there is a slight differ- ence in favour of the warmest months, comparing the results then obtained with those in the coldest. Of the want of agreement between Mr. Hunter's results and mine I can offer no satisfactory explanation. I have thought it right to advert to them, he being so deservedly a high authority in physiology. Were his results to be depended on, then, were the common fowl to be considered as a fair ex- ample of the temperature of birds generally, they could hardly be consi- dered as a class peculiar for highness of temperature, some of the mammalia having a temperature differing but little from that which he assigns to the common fowl f. Or, if not a fair example, then an exception, and the * Bead June 15, 1865. See Abstract, page 337. •f* The trials from which the last-mentioned results were obtained Jiave been made during the last two or three years, using a delicate thermometer of Negretti and Zambra made for the purpose, which had been compared with a standard instrument. The fowls tried were all barn-door fowls, living at large, and having the run of a field. The number of females examined was 37, of males 25. The mean temperature of the former in recto was 107°'64 ; the highest 109°, the lowest 107° ; of the latter the mean tempe- rature was 108°-25, the highest 109°, the lowest 107°. | In Ceylon I found the temperature of the blood of the wild hog, as it flowed from the divided great cervical vessels, 106°, and that of the pig in Engknd, in two instances, of the same degree ; both were in excellent condition, and were killed in December ; of one the temperature of the blood was tried ; of the other, the cavity of the abdomen. The temperature of the sheep I have found to vary from 103° to 105° in recto ; the latter in Ceylon. 1865.] Dr. Davy on the Temperature, fyc., of Birds. 441 common fowl would have to be placed amongst those birds, few in number, chiefly palmipedes, ocean-birds, peculiar for lowness of temperature *. Now, as neither of these conclusions is admissible, it seems unavoidable that Mr. Hunter's results must be received as inaccurate. II. Of the expired Air, and of the Air in the Air-receptacles and Bones of Birds. 1 . Of the expired air. — That which I have examined has been obtained from birds in the act of drowning. It is worthy of remark, I may premise, and I am not aware that the fact has been noticed by any previous in- quirer, that different birds vary as to their power of retention of life under water. The goose expires I have found in about ten minutes ; the duck in about the same time ; the common barn-door fowl in about four or four and a half minutes ; the turkey in about three minutes ; the jay in about a minute and a half ; the pigeon, the carrion-crow, rook, jackdaw, in about a minute ; the robin, the hedge-warbler in about the same time ; the black- bird in about three-quarters of a minute ; the tawny owl, the bullfinch, the house-sparrow, in about half-a-minute. Those birds which are capable of retaining the air longest emit little air commonly when first submerged ; but later, shortly before the extinction of life, they expel it in large quan- tities ; those, on the contrary, especially the smaller birds, which soonest die, expel no air in the act of drowning. I have examined the air from the goose in one instance only ; it was a portion of the last emitted. Tested by milk of lime and phosphorus, it was found to consist of 7'5 carbonic acid gas, 92*5 azote. The air from a duck, a small portion collected after four minutes' sub- mersion, was composed of 2*38 carbonic acid, 9'52 oxygen, 88' 10 azote. From another duck two portions of air were tried, one after five minutes' submersion, the other after between eight and ten. The first consisted of 7'5 carbonic acid, 7'5 oxygen, 85 azote ; the second of 15*7 carbonic acid, 4'1 oxygen, 80 '2 azote. From the common fowl the air was examined in two instances ; in both it was that which was emitted near death. Of one, the composition was 6'18 carbonic acid, 5'08 oxygen, 82'84 azote ; of the other, 3'3 carbonic acid, 779 oxygen, 88-89 azote. From a pigeon, the air emitted (it was pretty considerable in quantity) consisted of 11-1 oxygen, 89'7 azote. From these results, and from a few others which I have obtained, it would appear that in the air expired by birds in the act of drowning there * The temperature of the Procellaria (equinoctialis in one instance I found 103°'5 in recto, in another 105°. Dr. Brown-Sequard has made similar observations. See Ms 'Journal do la Physiologic' for January 1858. M. Ch. Martins has found the tempe- rature of some sea-birds even lower, that of Procellaria glacialis 102°, of Larusridi- bundus 104°. See his very interesting memoir on the Temperature of Northern Birds in the same Journal, and in the Number before quoted. VOL. XIV, 2 L 442 Dr. Davy on the Temperature, $c., of Birds. [1865. is a certain loss of carbonic acid, a loss equivalent to the proportion of oxygen less than exists in the atmospheric air inspired ; and it may be in- ferred that the deficient carbonic acid was absorbed and retained in the blood; and that it was so, was indicated by the very dark colour of the blood ob- tained by the division of the great cervical vessels immediately after the extinction of life, and further by the large quantity of air that was disen- gaged from the blood when subjected to the air-pump *. 2. Of the air from the air-sacs. — On the air from these receptacles I have made the following experiments : — From a turkey killed by drowning, a portion of air was collected by a puncture made under water into the air-vesicles under the sternum. It was found to consist of 15*5 carbonic acid, 84*5 azote. From a duck deprived of life in the same manner, a portion of air was obtained from the abdominal air-receptacles. It was composed of 10*52 carbonic acid, 5' 26 oxygen, 88'32 azote. These results would seem to warrant the inference that the very delicate membrane of which the air-receptacles are formed, is like that of the air- cells of the lungs pervious to air ; and the further inference, that the defi- cient carbonic acid in the air examined was owing to its absorption by the blood. 3. Of the air contained in the bones. — The experiments I have made on this air have been confined chiefly to that of the humerus. I may premise that in every instance in which I have examined the lining membrane of the hollow bones of birds (the air-containing bones), I have found it dis- tinctly vascular ; in this respect differing from the membrane of the ail* receptacles communicating with the lungs situated in its thoracic and ab- dominal cavities. Not unfrequently, both in the humeri and femora, the vessels have had the appearance of being varicose, and this when the ex- amination was made a few minutes after death. From the humerus of a common fowl, killed by drowning, a portion of air obtained was found to be composed of 4' 7 oxygen, 95'3 azote. The bone was dissected out under water, and its head there removed to allow free exit to the included air. From the humerus of another fowl killed by the division of the great cervical vessels, the air procured consisted of 8'3 carbonic acid, 8'3 oxygen, 83 '4 azote. In this instance the bone was dissected out underwater, whilst the fowl was still warm. No air escaped until the delicate bony tissue (the reticulated structure) was broken through, and indeed then but little, until the head of the bone had been removed. * Two trials of the blood were made, one in which the blood was received in water previously purged of air, the other in which it was received in weak solution of potassa, also exhausted of air by the pump : the difference was remarkable, so much air being disengaged from the first, so little from the second. It may be deserving of mention that in the instance in which the blood diluted with water was allowed to coagulate, no air was disengaged by the action of the pump until the resisting clot was broken up, when the disengagement on exhaustion was copious. 1865.] Dr. Davy on the Temperature, fyc., of Birds. 443 From a third fowl, a cock weighing ten pounds and three-quarters, killed in the same manner as the last, the air from the humerus, measuring one- tenth of a cubic inch, consisted of 15 oxygen and 85 azote. From the humerus of a rook, a few minutes after the bird had been shot, the air obtained, measuring '22 cubic inch, was composed of 11 carbonic acid, 89 azote. From the humerus of a tawny owl, three days after the death of the bird by drowning, the air collected consisted of 5*5 carbonic acid, 5'5 oxygen, 89 azote. Though these results are not so uniform as might be expected, they seem to prove that the air in the bones undergoes the same change as in the air- sacs, and that there is an absorption, more or less, of the carbonic acid formed by the blood contained in the vessels of the lining membrane, the quantity varying according to circumstances. It may be conjectured that the difference in the results may partly be owing to the air-passage, the fo- ramen or foramina, in the head of the bone, being more free in some in- stances than in others III. On Pulmonary and Cutaneous Aqueous Exhalation. The loss of water by exhalation from the lungs in the air expired, and from the cutaneous covering of the body by evaporation, must be con- sidered material elements in the problem of the animal heat of birds. And inasmuch as birds drink but little, inasmuch as their skin generally is very thin, dry, and little vascular; further, as the air in expiration has to pass over a considerable length of surface of comparatively low tempera- ture before it enters the open air, their loss of heat owing to these condi- tions must be small, and more especially so, taking into account the admirable covering of feathers, such bad conductors of heat, with which they are provided. The only experiments I have to describe bearing in part on what has just been stated, chiefly the last-mentioned, are the following on the rate of cooling. Two fowls, hens of the same brood, were selected for trial. The weight of each after loss of blood, having been killed by the division of the great cervical vessels, was five pounds. The temperature of one (No. I), ascer- tained just before, was 107°' 25 in recto ; of the other (No. 2), 108°. The latter was rapidly deprived of its feathers, with the exception of the wings, whilst on the other they were left on. Both were suspended by the legs, * I have occasionally found a delicate transparent membrane connecting some of the eincelli. Invariably the opening into the humerus is obstructed by the muscle attached to the cavity in which the foramen or foramina above mentioned are situated. Mr. Hunter found when the trachea of a cock was tied, and " the wing cut through the os humeri," the passage of air to the lungs was so difficult as to render it impossible for the animal to live longer than to prove that it breathed through the cut bone.— Observations on certain parts of the Animal Economy, p. 82. 2 L2 444 Dr. Davy on the Temperature, fyc., of Birds. [1865. the wings of the plucked fowl kept apart from the body, the wings of the other in close contact with the body. The room in which they were sus- pended was 53° at the time. From the great delicacy of the thermometer used, about a minute and a half sufficed in recto to give a good result ; as the same instrument was used, the trial was made alternately as to time ; iu the first trial of the temperature beginning with No. 1, in the second with No. 2, and so on. b- m 0 0 0 March 29th.— 10 2 A.M., air 53 No. 1, 107'25 No. 2, 108 10 40 „ 52 „ 104 „ 103 11 54 „ 52 „ 97 „ 87 1 P.M., air 52 „ 90 „ 72 24,, 52 „ 87 „ 66 37,, 52 „ 85 „ 62 42,, 52 „ 83 „ 61 „ 53,, 53 „ 80 „ 59-5 6 35 „ 50 „ 75-5 „ 55-5 „ 9 50 „ 50 „ 68 „ 52 March 30th. — 12 15 A.M., air 48 „ 65 „ 50'5 8 30 „ 49 „ 55-5 „ 48'5 10 20 „ 51 „ 55 „ 49 „ 12 15 P.M., air 53 „ 54 „ 50 From the last of these observations it is seen how little was the cooling effects from evaporation, the temperature of the plucked fowl rising a degree, and differing one degree only from the air of the room. Of the other trials made, one was on a drake, one on a tawny owl. The drake, well covered with feathers, weighed seven pounds. It was killed by drowning; the blood was retained. Like the fowls, it was suspended by the legs ; its wings were apart. Previously its temperature in recto was 107°'5. The thermometer was left in recto. h m o o April 5th.— 10 51 A.M., air 55 Drake 107-5 ., „ 11, 25 „ 55 „ 104. „ 1 2 40 „ 55 „ 94. „ 28 „ 55 „ 89-5. 3 15 „ 55 „ 85. 4 35 „ 55 „ 81. 55 „ 55 „ 65. „ 11 45 „ 53 „ 65. April 6th. — 8 30 A.M., air 51 „ 57. The owl was killed also by drowning. It had been fed the preceding evening. On the 2nd of December, when alive, at 10.30 A.M., its tem- perature in recto was 106°- 5. Tho observations on its cooling were made on it placed on a table, the bird resting on its abdomen, the wings close to its sides j the thermometer was left in recto. 1865.] Dr. Davy on the Temperature, £$c.} of Birds. 445 December 2nd.— 10 45 A.M., air 58 „ 11 45 „ 58 „ 12 45 P.M., air 58 „ 1 45 » 58 » 2 45 „ 58 }> 3 45 58 M 4 45 57 » 7 15 „ 57 „ 9 30 „ 56 » 11 30 55 December 3rd .— 9 A.M., air 55 ,, 12 M., air 58 »> 2 P.M., „ 60 ti 4 60 „ 12 „ 57 December 4th . — 9 A.M., air 58 » 4 P.M., air 60 „ 12 57 Owl .... 100 „ 93-25 „ 86-25 „ .... 80-50 „ .... 75'75 „ .... 72 „ .... 69-25 „ .... 64-50 „ 61-25 „ .... 59-25 „ .... 54-5* „ .... 56-25 „ .... 57 ,, .... 58-5 „ 57 „ 55-5f „ .... 58-5 „ 57 These results seem sufficient to show that birds owe much of their high temperature, especially its preservation, to their clothing of feathers. Further, it may be remarked in proof of the little activity of their cuticular structure (except, indeed, in the growth of feathers), that birds are never observed to eat, or have their feathers wet from condensation on them of perspired moisture ; nor am I aware that their breath becomes visible, to use a popular expression, in the coldest weather. And in accordance it would appear, comparing birds with animals of other classes, that the proportion of their aqueous element is somewhat less, which also harmo- nizes with an inconsiderable cooling effect from cutaneous evaporation — a fact which some of the results given seem to prove, and as is shown by the following, so far as trials on the dead are applicable, inferentially to the living animal. Of four sparrows just shot, one (No. 1) weighing 414*5 grs. was sus- pended with its feathers entire ; a second (No. 2) clipped, i. e. its feathers cut short, weighing 405-6 grs. (it had lost 23 grs. by the clipping), was suspended by its side, as were also the other two ; No. 3, deprived of its feathers, its skin unbroken, weighing 414 grs. ; No. 4, deprived of its skin as well as its feathers, weighing 384-5 grs. During twenty-four hours' exposure to the air of room varying from 48° to 50°, No. 1 lost 1-5 per cent.; No. 2, 2-3 ; No. 3, 7'9 j No. 4, 17'4. * In the room there was no fire from 5 P.M. on the 2nd to 8 A.M. on the 3rd ; during the night the thermometer in air must have been below 54° -5 ; in a small cup of water close to the bird at 9 A.M. it was 53°. t Water in cup covered 55°. 446 Dr. Davy on the Temperature, $c., of Birds. [18G5. IV. — Of the Kidneys and their Excretion. Another element in the problem of the temperature of birds is the kidneys, with th excretion. , As is well known, these organs in birds are propor- tionally large and active,; their secretion, not inconsiderable in quantity, and formed chiefly of urate of ammonia, is voided in a state far removed from the liquid, hardly semifluid from the little water it contains. Hence in the performance of .the .function there is but little loss of heat. Moreover, as it would appear from ultimate analysis that the urate contains less oxygen than urea, there must be a less expenditure of oxygen in its forma- tion, leaving more for a more profitable conversion into carbonic acid. What are the general conclusions which are admissible from the pre- ceding results ? Do they not warrant the inference that the high temperature of birds is owing to a combination of circumstances, some positive, some negative; the one, the positive, acting through the air inspired and the conversion of oxy- gen into carbonic acid gas, productive of heat ; the other, the negative con- ditions, such as those mentioned, influential mainly by economizing the heat when produced, or checking its escape ? Besides these negative conditions, it may be open to question, consider- ing the proportional smallness of the lungs of birds, and the smallness of the nerves with which they are supplied, whether there are not other cir- cumstances concerned of an ancillary kind — such, to enumerate some of the most probable, as a powerful heart, especially a powerful left ventricle; the quality of their blood, that but little viscid, as indicated by the little, if any tendency of the red corpuscles to collect in piles * ; the large pro- portion of these corpuscles, and their nucleated structure, a structure with which may be connected an electrical influence. If the chief use of the peculiar pneumatic system of birds be to secure a high temperature, it is probable, and is in part already admitted, that it may subserve other uses inferior only in degree of importance in relation to the habits and well-being of the class : for instance, as generally ad- mitted, it may conduce to great power of flight in some, to running power in others, to vocal power in a third ; and, in all, may not the thorough aeration of the blood, as denoted by its more florid hue even in the veins, be essential to the energy, to that intensity of action and endurance for which the muscles of those birds in which the structure under considera- tion is most developed, are so remarkable ? The subject in its entireness, it must be allowed, is full of interest. It affords in the variety of structure exhibited by different birds, supple- mentary to the lungs, ample scope for further research. Why some birds, such as the woodcock, the snipe, the swallow, birds of rapid and long flight, should be destitute of air in their bones ; why the small birds, with few exceptions, the tits for instance, some of the smallest, should expe- * In no instance have I seen the blood-corpuscles of any bird to cohere and form rouleaux or piles, nor have I seen a buffy coat on the blood of birds. 1865.] Dr. Davy on the Temperature, fyc., of Birds. 44-7 rience the same exemption ; why one bird, the apteryx, a solitary example should be without air not only in every part of its osseous system, but also without air-sacs ; and another bird, the grouse, not remarkable for power of flight, should have air in its femora as well as humeri, are questions which at present it may be difficult to answer, but which, it may be hoped, were careful and minute inquiry instituted, might be satisfactorily accounted for on the teleological principle of fitness of structure to use. If I may be allowed to offer a conjecture, it seems to me probable that in our commonly received generalization relative to the consumption of oxygen in the respiration of birds, the quantity presumed to be used has been overrated, and that in many instances the expenditure of this gas may be found to be less proportionally than in the mammalia. As supplementary to the preceding observations, I would beg to state some further particulars respecting birds, the results of the inquiry in which I have been engaged. 1st. Of the birds examined. — All of them were natives of the Lake Dis- trict, with two or three exceptions which will be specified, and all were obtained between November and March, excepting those marked with an asterisk, which were shot in April and May, They may be divided into two sections, one including those birds in one or more of the bones of which air was found to exist communicating with the lungs. The other, of those birds in which in the corresponding bones no air could be detected. The birds were all at least one year old, an ample time, I apprehend, for the marrow which exists probably in the bones of every individual of the class at the time of hatching, and for some time after, to be absorbed in those in which it is not permanently present. It may be right to remark that in every instance the question whether air was present or not was determined bv an examination of the contents of the particular bones, and not merely from their appearance, which, as regards colour, is sometimes deceptive. Of the birds belonging to the first section, the bones, which are named after each, were those only in which air was found, i. e. communicating with the lungs. SECTION I. Buzzard (Falco buteo) humeri, scapulae, clavicles, furcula, femora. Tawny owl (Strix stridula) do. do. do. do. do. Carrion crow ( Corvus corone) do. do. do. do. — Rook (C.frugilegus) . do. do. do. do. — Jackdaw (G. monedula) do. do. do. do. — Magpie (G. pica) do. do. do. do. — Jay (G. glandarius) do. do. do. do. — Cuckoo (Cuculus canorus) do. — — — Common fowl (Gallus domesticus) do. — — — Pheasant (Phasianus colchicus) do. — — — — 448 Dr. Davy on the Temperature, fyc.} of Birds. [1865. Grouse (Tetrao scoticus) .... humeri, scapulae, clavicles, furcula, femora. Partridge (Perdix cinerea) do. — — — Wood-pigeon (Coluinba palustris) do. — — — Common pigeon (C. domestica) do. Wild duck (Anas boschus) do. Common duck {A. domesticus) do. — Wigeon (A. Penelope) do. — — — Skylark (Alauda arvensis) do. do. do. — Woodlark (A. arbored) do. do. do. — — Great tit (Parus major) do. — Blue tit (P. cceruleus) do. Marsh tit (P.palustris) do. — SECTION II. •Titlark (Anthuspratensis). Tufted duck (Anas fuligula). Common guillemot (Uria, Troile). Water-hen (Gallimda chloropus). *Corncrake (G. crex). Woodcock (Scolopax rusticuld). Snipe (5. yallinago). Bar-tailed godwit (S. ceyocephala). Dunlin (Tringa alpina). Little sandpiper (T. pusilld). Missel-thrush (Turdus viscivorus). Blackbird (T. merulci). Song- thrush (T. musiciis). Redwing (T. iliacus). Fieldfare (T. pilaris). Water-ouzel (T. cinclus). Starling (Sturnus vulgaris). Goldfinch (Fringilla carduelis). Chaffinch (F. ccelebs). Siskin (F. spinus). Lesser-redpole (F. linaria). Common sparrow (F. domestica). Mountain linnet (F. montana). Robin (Sylvia rubecula). *Stonechat (S. rubicola). Wren (S. troglodytes). *Hedge-warbler (S. modularis). *Blackcap (S. atricapilla). *Redstart (S. pheenicura). *Willow warbler (S. trochilus). Bullfinch (Loxia pyrrhula). 1865.] Dr. Davy on the Temperature, $c.} of Birds. 449 *Greenfinch (L. Moris), Yellowhammer (Enteriza citrinella). Gray wagtail (Motacilla boarula). Yellow wagtail (M.flava). Common creeper (Certhiafamiliaris). *Pied flycatcher (Muscicapa atricapilla) . * Spotted flycatcher (3/. grisold). * Swift (Hirundo apis}. * Swallow (H. rustica}. *Martin (H. urbica). *Sand-martin (H. riparia). Of the birds in each section, the crania, with some exceptions, contained air. The skull of the water-ouzel is one of the exceptions. It is not cel- lular like that of the majority, but compact and sinks in water. Its greater heaviness may be suitable to the habits of the bird, seeking its prey in the bed of ruuning streams with its head downmost. The same compactness of bone is seen in the crania of the Scolopacidse. This compactness is remarkably contrasted with the cellular state of cranium of certain other birds, in which it is most strongly marked, where lightness as well as power of resistance is needed, such as that of the owls and tits. There are certain bones which in the adult stage of the bird appear to be without both marrow and air ; the scapular arch is occasionally an ex- ample of this, especially its posterior wing*, and also the sternum. Professor Rudolph Wagner, in his 'Elements of Comparative Anatomy' (English translation), refers to the blackbird and thrush as instances of birds which have air in their femora. I have sought for air in these bones in all the thrushes I have examined, seven different species, but have found only marrow. If verified it would be a curious fact, that in one country air should occur in the bones in question and in another marrow. Whether the circumstance of the presence or absence of air in the bones is deserving of attention in the classification of birds, may be worthy of the consideration of the naturalist. In all the tits I have examined, and the number has been considerable, especially of the blue tit, I have never found marrow in the humeri, and the same remark applies to these bones in the larks, but not to those of the pipits. 2nd. Of the proportions of certain parts of birds as determined by weigh- ing.— In the Table which follows a statement is given of results, comprising the weight of the birds examined, of their feathers, and, with a few excep- tions, of their bones, the latter after having been cleaned, deprived of their periostrum, and dried by exposure to the airf. In the first column the * The posterior wing in the tabular list is designated scapula, the anterior portion, the coracoid process of some authors, is designated clavicle. t In one instance (the bones of the buzzard) it was found, by weighing them before and after drying, that the difference or loss was 12'5 per cent. 450 Dr. Davy on the Temperature, fyc., of Birds. [1865. weight in grains of the fresh birds, before the removal of their feathers, is inserted, the heading of the other columns is sufficiently distinctive. The primates of the wings and the quill-feathers of the tail in each instance were weighed apart. The weight of the whole of the plumage was ascertained by two weighings, one before, the other after the feathers had been taken out, the loss, including the whole of the quill-feathers, showing the total amount. When a trial was made of more than one of a species, the results have been inserted, on the idea that possibly they may be of some interest in relation to variations ; these no doubt depending on many circumstances, such as sex, condition as to fatness, and others less easy of appreciation. Specie,. Sex. Weight bird. Weight of tail- feathers. Weight of wing- feathers. Total weight of feathers. Weight of bones. Buzzard F. 23040 grs. 128 5? 2276* grs. 1163-6 Buzzard M. 12994 89 330-5 2022 1050*8 M 5776 22'6 127*6 696*2 428*5 M 7885 48-4 223-6 1074 556*9 Rook .... F 8664 45 207-3 1122-3 537 Rook M. 6556 45-5 201-6 974 463*7 Jackdaw M. 3900 28 98 390 272*5 Jay 2539 14-9 43.7 250-4 152*2 M 2091 23-6 49 197-6 106-9 F 24851 57*5 214 1846*5 1438*7 Common duck Woodcock F. 22547 4198 30 8-1 160-4 58-9 1755-5 306 280 Little sandpiper Blackbird -. 629-4 1668 1-7 8-1 8-8 20-2 62-7 104*5 36*6 81*3 Song-thrush Missel-thrush ... 1175 2127 4 12 76*5 156 Water- ouze 873 3 6-5 53*2 46*9 Skylark F 744 56*6 Skylark M. 657-7 53-2 33*2 Skylark F 643-7 2-8 12*2 64*7 Skylark F. 523 2-6 9-1 47*9 24-2 Woodlark F 493 2-3 9'1 47 24*2 Titlark F 368 1*5 5*4 14*5 20*2 Black-cap M 273-2 1-2 3-3 19-7 12*4 Stone-chat M 346-8 1-8 6-2 34-8 21-4 House-sparrow 421-7 2 5-7 30-6 25-3 Chaffinch 401 19 Bullfinch M 374 1'9 5*9 31*9 15-3 Greenfinch M 388-6 1-5 5 34-1 22 Swallow F 321-8 1'8 8-1 25-8 16 Swift F 784-3 9 18 55-3 39*5 Martin F 301 1-3 7 21 14*6 Sand-martin F. 210-5 •9 6-2 14-5 9*4 320-5 1-5 4 22 Blue tit 180-9 •95 1-15 18'4 Blue tit . . M 162-1 •83 2-16 16*49 8*71 Blue tit 145 15'4 Blue tit 137 13*5 Blue tit . 167-5 13-8 On the results in this Table I have but few remarks to offer. The regu- larity of feathers as to number, i. e. of the primates of the wings and of 1865.] Dr. Davy on the Temperature, fyc., of Birds. 451 the quill tail-feathers, is well known to the naturalist. In all the instances in which I have weighed the primates of each wing, I have found them, if not precisely of the same weight, to diifer in the smaller birds not more than by pl or '01 grain, and in the larger the difference has rarely exceeded 1 grain ; a degree of equality this which might be expected, as essential to the regularity of flight ; and small as it is, I am disposed to think that in the larger birds even it would hardly be appreciable could the quills be extracted with precisely the same proportion of adhering tissue. Comparing the quill-feathers of the small with those of the large birds, the proportional weight of the latter, it would appear, is commonly greater than that of the former, — a disproportion, it may be inferred, connected with the larger birds having, as needed, stronger wing- and tail-quill fea- thers, and, indeed, stronger feathers generally, the few exceptions harmo- nizing, at least those of the common fowl and duck. Comparing their bones, those of the larger and more powerful, as might also be anticipated, appear, too, proportionally heaviest. Comparing individuals of the same species, whether as to the total weight of birds, or of feathers and bones, variations will be found to occur. The skylarks may be mentioned as examples, and also the tits, the former ob- tained not from the same locality, one having been procured from Lincoln- shire, one from Oxfoid, a third from Yorkshire, a fourth from the imme- diate neighbourhood of Ambleside, where it is rarely seen, and where it came during a severe frost probably in quest of food, having been found close to a running stream* ; the tits were all from the immediate neigh- bourhood of Ambleside. 3rd. Of the weight of the principal bones of the skeleton, — The results obtained are given in the next Table. The birds, the bones of which were the subjects of trial, have already been all mentioned, and may be identified by their weight, as inserted again in the first column. With the cranium, it may be stated, the maxillae and facial bones were weighed, and with the pelvis the caudal vertebrae : the spine comprised all the other vertebrae excepting those anchylosed with the pelvis ; the terminal bones of the extremities are designated by metacarpi, &c. for the upper, and by phalanges for the lower. * In the gizzard of all the larks I have examined I have found grass, tending to prove that, at least in winter, meadow-grass is their chief food. 452 Dr. Davy on the Temperature, $c., of Birds. [1865. •;

o> t^Mi cct^co ^-i ,_, eo w ao co o cp >n cp

• «^ rp r-i ' H ' • -^<^HCpcp«pc>pcp *? T1 7* ® T1 ' **«-l cp cp in coco-^^-i^^-i «-*'.i>-ccc^ioo : : 2 ; 'H'S I o e : ii i H i iJ.|.i i i i I i I 1865.] Dr. Davy on the Temperature, fyc., of Birds. 453 The results given in the preceding Table may justify the remark, — aeon- elusion that might be anticipated, that generally the comparative weight of the bones of each species of birds bears a relation to the power exercised by the limbs on parts to which they belong ; of this striking examples are afforded in the instances of the upper and lower extremities of the buzzard and common fowl ; of the one, the buzzard, a bird of powerful flight, the wing-bones are proportionally the heaviest ; whilst of the other, the fowl, which makes so little use of its wings and so much use of its legs, the opposite is the case ; and other contrasts not less striking are noticeable. Also, as might be anticipated, and in accordance with what was before observed of the feathers, the primates of each wing, the weight of the bones of each was found to be nearly the same, the difference being no greater than might be expected from the mode of preparing them. 4th. Of the Composition of some of the principal bones. — This was ascertained by calcination, by which merely the proportion of animal or combustible matter was determined and that of the incombustible, chiefly phosphate of lime. I shall first give the results of the trials on humeri and femora : in each instance the shafts of these bones were selected ; and previously to a thorough drying over steam, they were deprived of their investing membrane internally as well as externally. Though the quantities employed did not exceed a few grains, and were even less than a grain from some of the smaller birds, yet as the weighing was carefully made to the one hundredth of a grain, the results may be received as tolerably reliable for comparison. Hum eras. Fern ur. Phosphate of lime. Animal matter. Phosphate of lime. Animal matter. 69-53 grs. 30-47 68-80 31-20 Owl 68-50 31-50 71-20 28-80 Rook 69 20 30-80 70-70 29-30 Jackdaw 70-30 29-70 71-30 28-70 67-70 32-30 71-40 28-60 Common fowl (cock "1 two years old j 70-22 74.70 29-78 25-30 71-40 73-40 28-60 26-60 Skylark 77-00 2'J-OO 72-00 28*00 Blackbird 71-60 28-40 76-20 23-40 71-10 28-80 71-90 28-10 70-70 29-30 72-50 27-50 72-80 27-20 73-23 26-77 Guillemot 70-10 29-90 67-60 32-40 If inferences may be drawn from these results, they seem to favour the conclusion, first, that the proportion of phosphate of lime is somewhat greater in the bones of birds, the cylindrical of the extremities, than in the like bones of the Mammalia ; and secondly, that the composition of those con- taining air and of those containing marrow is much the same, which is not 454 Dr. Davy on the Temperature, $c., of Birds. [1865. in accordance with a statement that has been made, that the former have a larger proportion of earthy constituents *. It may generally be stated, I believe, that the composition and structure of each particular bone has relation to its function, — that where unyielding resistance is required, there, cceteris paribus, the proportion of phosphate of lime is largest, as witnessed in the majority of the long bones of the ex- tremities ; that where yielding and elasticity are needed, the proportion of animal matter is somewhat more considerable, as seen in the sternum, cra- nium, ribs, and maxillae. Also it may be generally stated, I believe, that in different species of the same family or genus of birds, the composition of corresponding bones varies comparatively little ; and that where there is a variation, it too is connected with use, irrespective of size. And the same remark, I am dis- posed to infer, would be near the truth relative to the proportional weight of the bones in different species. The following results are offered in illustration. First, of the cranium. The portion subjected to calcination was that covering the cerebrum. grs. grs. Buzzard 69 '7 phosphate of lime, 39 '3 animal matter. Carrion crow. . . „ . . 59'5 „ 40'5 „ Rook 60-1 „ 39-9 Jackdaw 59'5 „ 40'5 „ Magpie 60'0 „ 40'0 „ Owl 57-4 „ 42-6 Common fowl .... 60'0 „ 40'0 „ Common duck 60'0 „ 40'0 „ Woodcock 58-2 „ 41-8 „ Skylark 63'0 „ 47'0 Blue tit 58-0 „ 42-0 Water-ouzel 57'5 „ 42*5 „ Godwit, bar-tailed . 60'0 „ 40'0 „ Dunlin 67'0 „ 33'0 Of the above, some of the crania were cellular, others were compact, sinking in water. The crania of the owl and water-ouzel, as already men- tioned, are extreme examples, and yet their proportion of phosphate of lime and animal matter is much the same, both conditions of bone, the very cellular structure of the one, and the compact structure of the other without cells, being suitable to the habits of the individual, — in the owl, great strength with lightness ; in the water-ouzel, strength with a compa- ratively high specific gravity. The following is the composition of the sternum of a few of the same birds, illustrative of the quality of lightness coupled with a considerable degree of yieldingness, which in the moist bone is very observable. The * Op. cit. p. 69. 1865.] Dr. Davy on the Temperature, $c., of Birds. 455 perpendicularity of the crest or keel of this bone, I may remark, is very characteristic of the equality of action of the great pectoral muscles attached to it. grs. grs. Buzzard .......... 55 phosphate of lime, 45 animal matter. Stork ............ 54 „ 46 ;, Carrion crow ...... 54 „ 46 ., Jackdaw ........ 55 „ 45 Skylark .......... 58 „ 42 The composition of the maxillae of a very few birds is given illustrative of the same quality. The lower jaw has been selected, and it has been divided, its anterior portion deprived of its horny integuments ; its posterior, including its head, have been taken for the sake of comparison, the one being more elastic than the other. Phosphate of lime. Animal matter. Phosphate of lime. Animal matter. grs. grs. grs. grs. Buzzard. Anterior portion 64-8 35 •2 Posterior 67-0 43-0 Song-thrush. „ 56-3 43 •7 H 59-1 40-9 Carrion crow. » 52-1 47 •9 „ 56-8 43-2 Godwit . . . »> 64-8 35 •2 M 67-0 33-0 * Here I would beg to offer a few remarks more on the subject of the bones of birds. It is stated, and by so high an authority as Professor Wagner, that their hollow bones are whiter than those filled with marrow. Gene- rally this is a fact, and for the reason that, being translucent, the latter owe their colour to the marrow within them. Accordingly their colour varies with the colour of the marrow. Thus in some in which the marrow is of a light hue, almost white, as in the instance of the tawny owl, its ulnse and radii are so white as to suggest their containing air. In another (the yel- low-hammer), in which the marrow is of a bright yellow, as is also the fat, the long bones have the same hue. The same hue is seen in the bones of the cuckoo, and from the same cause, and also, but in a less degree, in those of the greenfinch. Nor are there wanting examples of a dark colour of the bones, from a dark colour of the marrow : those of the little sand- piper may be mentioned as an instance. Generally it may be remarked that the femora are darker than the humeri ; and that the lower portion of the tibiae is very much lighter than their upper, corresponding to the colour of the marrow in each. Another circumstance influencing the colour of the bones of birds is the degree of thickness of their walls. The thicker * The bone of the under bill of the godwit, like that of the majority of the long-billed birds, is very slender and remarkably elastic, especially its anterior portion, that which is covered with integuments and a hard horny cuticle ; the same portion is cellular and very vascular, suitable for renewing the growth of the beak as it is wasted in use, a remark more or less applicable to the beak of birds generally. 456 Dr. Davy on the Temperature, fyc., of Birds. [1865. they are, the less translucent they are, and consequently the lighter is the colour, being less affected thereby by that of their contents. The long bones of the common guillemot, and also of the corn-crake, the parietes of which, especially of the wing-bones, are more than ordinarily thick, may be mentioned as illustrative examples. In a preceding part of this paper I have referred to the size of some of the more important organs of birds. lu many instances I have ascertained their weights. As examples, those of five different species are selected, and I give them without comment. 1. Tawny owl. Weight 5776 grs. April 7.' grs. Brains, its membranes detached 139 Eye freed from muscle and fat 91 Lens (-58 inch diameter) 1 9'6 Skin freed from most of its fat 250 Membranous stomach 115 Liver without gall-bladder 1 54'7 Spleen 1 4'6 Pancreas 9'5 Kidneys 577 One lung, it contained a little coagulated blood 13'2 Heart freed from fat 39 Testes (no spermatozoa could be detected in them) .... 2*5 Great pectoral muscles 634 Other muscles of chest, those attached to furcula and sca- pular arch, exterior of costal 198 Muscles of humeri 188 Muscles of ulnae and radii 156 Muscles of femora 272 Muscles of tibiae 346 2. Rook. Weight 6556 grs. April 19. Brain freed from its membranes 1 18*6 Eye formed from muscle and fat * 41 Skin, exclusive of that of tarsi and phalanges, or very little fat adhering 344 Gizzard 208 Liver, gall-bladder detached 167 Spleen 2-8 Pancreas 23'2 Kidneys 72'6 * Of another male rook, shot April 29, and examined whilst still warm, the eye weighed 37-6 grs., the lens 1-2 gr. ; it was very soft ; evaporated to dryness it lost '75 gr., or 62-5 per cent, of water. The lens of the rook, of that of which the weight of the organs is given above, was almost as liquid as the vitreous humour. 1865.] Dr. Davy on the Temperature, fyc , of Birds. 457 One lung ; it contained a very little clot 46 The other ; it contained a little more * 49 Heart freed from fat 77 Testis, spermatozoa were abundant in its ducts 67 Glandula uropygii f 107 Great pectoral muscles 960 Muscles attached to scapular arch and bones of wings . . . 493 Ditto, of lower extremities 680 3. Common fowl, a hen. Weight 24,851 grs. Brain 53 Eye 30 One lung 53 The other ; it contained a little clot 60 Gizzard 466 Spleen 27 Pancreas 36 Kidneys 181 4. Swallow, female. Weight 321-8 grs. May 5. Brain 8 Heart 4-6 Liver 1 7'8 One lung 1 ' 7 Stomach 8 Pancreas '3 Spleen. '5 Kidneys 6'6 Great pectoral muscles 75 5. Cuckoo. Weight 2091 grs. May 3rd. Brain 26'3 Eye 29 Lens 2-3 Liver 347 Spleen 7 Pancreas 1 -6 Kidneys 18 Stomach 33'2 Testis 1-3 * By steeping in water and expressing the blood the first was reduced to 32-7 grs., the second to 26-2 grs.' t The whitish semifluid expressed from it consisted of very miuute oil-globules, and of the casts of the secreting tubes. VOL. XIV. 2 M 458 Messrs. Frankland and Duppa. — Synthetical [Nov. 16, November 16, 1865. Lieut.-General SABINE, President, in the Chair. In accordance with the Statutes, notice of the ensuing Anniversary Meeting for the election of Council and Officers was given from the Chair. Mr. Bowman, Dr. Frankland, Mr. F. Galton, Sir John Lubbock, and Mr. Spottiswoode, having been nominated by the President, were elected by ballot Auditors of the Treasurer's accounts on the part of the Society. Mr. George Robert Gray was admitted into the Society. The following communications were read : — I. " Synthetical Researches upon Ethers. — Synthesis of Ethers from Acetic Ethers." By E. FRANKLAND, F.R.S., Professor of Chemistry in the Royal Institution of Great Britain, and in the Royal School of Mines, and B. F. DUPPA, Esq. Received July 13, 1865. (Abstract.) In a recent note * we have briefly described the synthesis of butyric and diethacetic ethers by acting consecutively upon acetic ether with sodium and the iodide of ethyl. In the present paper we have the honour to lay before the Royal Society the detailed results of one section of this research, embracing the action of sodium and the iodides of methyl, ethyl, and amyl upon acetic ether. I. Action of Sodium and Ethyl Iodide upon Acetic Ether. When acetic ether is treated with sodium at a temperature gradually rising to 120° C., hydrogen is evolved, and a thick brownish liquid pro- duced ; the latter solidifies on cooling to a yellowish mass, presenting the appearance of beeswax. On digesting this solid mass with ethylic iodide at 100° C. for several hours, a number of products are formed, which on the addition of water, may be distilled off from a residue consisting chiefly of iodide of sodium. The distillate can readily be separated into an aqueous and an oily portion. The latter then presented the appearance of a light straw-coloured oil, possessing a pleasant and fragrant odour. It was washed and then dried over chloride of calcium, and submitted to fractional distil- lation, by which traces of alcohol, acetic ether, and ethyl iodide were effectually removed from the other products, which now boiled between 120° and 265° C. We have described the constituents of this complex liquid under two distinct heads, viz. :• — 1st. Products depending upon the duplication of the atom of acetic ether. 2nd. Products derived from the replacement of hydrogen in the methyl of acetic ether by the alcohol-radicals. In order successfully to separate the two products from each other, and * Proceedings of the Royal Society, vol. xir. p. 198. 1865.] Researches on Ethers. 459 especially to disentangle their constituent compounds, it is absolutely ne- cessary to operate upon large quantities of material. But if this be done, there is obtained a considerable quantity of the products of the first divi- sion boiling between 204° and 208°, whilst the products of the second di- vision boil considerably below these temperatures. a. Examination of the products depending upon the duplication of the atom of acetic ether. Submitted to analysis, this liquid was found to consist of two bodies of the formulae C10H1803, and C8 H, O43, separable from each other by repeated rectification, and also by the action of boiling aqueous potash, which decomposes the second but scarcely affects the first. From the results of the analysis, and from considerations which are fully entered into in the paper, we propose for these bodies the following names and formulae : Ethylic diethacetone carbonate Ethylic ethacetone carbonate . or— Lo C2 H5 The production of ethylic diethacetone carbonate is explained in the fol- lowing equations : ;H, cr OC2H5 Acetic ether. Ethylic diethacetone carbonate. Ethylic diethacetone carbonate is a colourless and somewhat oily liquid, possessing a fragrant odour and a pungent taste. It is insoluble in water, but miscible in all proportions with alcohol and ether. Its specific gravity is '9738 at 20° C. It boils between 210° and 212°, and distils unchanged. 2 M 2 460 Messrs. Frankland and Duppa — Synthetical [Nov. 16, The density of its vapour was found to be 6'59. The above formula, cor- responding to two volumes, requires the number C'43. Boiling aqueous solutions of potash and soda have scarcely any action on ethylic diethace- tone carbonate, but baryta-water and lime-water decompose it with great fa- cility, as do also boiling alcoholic solutions of potash and soda. In all cases a carbonate of the base is precipitated, and alcohol, together with a light ethereal liquid, is separated. This liquid, freed from alcohol by repeated washing with salt and water, boiled, after drying over chloride of calcium, between 1370<5 and 139° C. Submitted to analysis, it yielded results corresponding with the formula C7HU0. We regard this body as diethylated acetone. Its formula and its rela- tions to acetone may be thus expressed : JCH3 JCEt2H \CMeO \CMe° Acetone. Diethylated acetone. Diethylated acetone is produced from ethylic diethacetone carbonate by the action of alcoholic potash according to the following equation : w fo (C2H.)2 + 2KH O=C j OK4-C2H5O j (yi [ O K Alcohol. LO C2 H5 Potassium Ethylic diethacetone carbonate. carbonate. Diethylated acetone is a colourless, transparent and mobile liquid, possess- ing a penetrating odour of camphor, and the burning and bitter after-taste of the same substance. It is very slightly soluble in water, but miscible in all proportions with alcohol and ether. Its specific gravity is '8171 at 22° C. It boils at 137°'5 to 139° C. A determination of its vapour-density gave the number 3'86, the above formula requiring 3'93. Diethylated acetone does not oxidize in the air, neither does it reduce ammoniacal solution of nitrate of silver when boiled with it. Mixed with concentrated solution of sodium bisulphite, it forms an oily compound which scarcely exhibits signs of crystallization at 0° C. It suffers no alteration by prolonged boiling with alcoholic potash. It is isomeric with butyrone, with a ketone ob- tained by Fittig * in the distillation of calcium valerianate, and with oenan- thol. From the first it is distinguished by its lower boiling-point (138°), butyrone boiling at 144° C., aud Fittig's ketone at 161° to 164°, and from the third by its different properties, which are essentially those of a ketone and not of an aldehyde. The difference in structure of three of these bodies may be expressed with considerable certainty by the following formulae : / C Et2 H / C Et H2 f C (Aq) H2 \CMeO \C(Pr)0 \CHO Diethylated acetone. Butyrone. (Enanthol. Ann. Ch. Pharm., vol. cxvii. p. G8. 1865.] Researches on Ethers. 461 Ethylic ethacetone carbonate is produced by the action of sodium and ethylic iodide upon acetic ether, according to the following equations : (TT O7' +Na=C4^ £a +C2H,0 OC,H5 I jj» Acetic ether. LOCH Ethylic sodacetone carbonate. + NaI. lOC2H5 ^OC2H5 Ethylic sodacetone Ethylic ethacetono carbonate. carbonate. Ethylic ethacetone carbonate is a colourless and transparent liquid, pos- sessing a very fragrant odour and an aromatic taste. It is nearly insoluble in water, but miscible in all proportions with alcohol and ether. Its den- sity in the liquid condition is -9834 at 16°C. It boils at 195° C., and distils without decomposition. A determination of its vapour-density gave the number 5 '36. The above formula requires 5'45. Ethylic ethacetone car- bonate is readily attacked by boiling aqueous solutions of potash and soda, yielding carbonates of these bases, alcohol, and ethylated acetone, according to the following equation : fH3 I5L_ f0" fS. + 2KHO=C OK 0" Alcohol. IOC,, H, Ethylated Ethylic ethacetone acetone, carbonate. Ethylic ethacetone carbonate is still more readily decomposed by aqueous solution of baryta and by alcoholic potash, in both cases ethylated acetone and a carbonate of the base is produced. Ethylated acetone may be freed from alcohol by repeated washing with salt and water, but it is best obtained in a state of absolute purity by com- bination with, and subsequent separation from, bisulphite of soda. Ethyl- ated acetone thus purified and rectified from quicklime yielded on analysis numbers agreeing well with the formula which may be reduced to the radical type as follows : 462 Messrs. Frankland and Duppa— Synthetical [Nov. 16, 3 t C H3 O" _r JP^_ _ JCEtH2 HC'CaH.- \CMeO Its relations to acetone and diethylated acetone are then clearly seen in the following formula, /CH3 JCEtH2 JCEt2H \CMeO \CMeO \CMeO Acetone. Ethylated Diethylated acetone. acetone. Ethylated acetone is a colourless, transparent and very mobile liquid, possessing a powerful and pleasant odour, in which that of camphor is slightly perceptible. Its specific gravity is '8132 at 13° C., and '8046 at 22° C. It boils steadily at 101°-5, and its vapour has the density 2-951, the above formula requiring 2*971. Ethylated acetone neither absorbs oxygen from the air, nor reduces ammoniacal solutions of silver. It yields with concentrated solutions of bisulphite of soda a compound in large and brilliant crystals, which are quite permanent in the air, and which at once distingush it from diethylated acetone, the latter producing under the same circumstances an oily compound. Ethylated acetone is not altered by pro- longed ebullition with alcoholic potash. j3. Examination of the products derived from the replacement of hydro- gen in the methyl of acetic ether by ethyl. The chief results of this examination are given in the note above alluded to *, and we have only to add that ethacetic acid is identical with butyric acid, whilst diethacetic acid is isomeric with caproic acid. II. Action of Sodium and Methylic Iodide upon Acetic Ether. This reaction is conducted in substantially the same manner as that above described, and the products are completely homologous. Thus there are produced two carboketonic ethers, and an ether derived from acetic ether by the substitution of methyl for hydrogen. The latter has been already described in our previous communication on this subject. The following are the names and formulae of the carboketonic ethers : — (9 Ethylic dimethacetone carbonate . . C4<( / OC2H5 H, O" p CT Ethylic methacetone carbonate . . CtJ -- • lo77"" Lqc.H, * Proceedings of Eoyal Society, vol. xiy. p. 198. 1865.] Researches on Ethers. 463 The reactions involved in the production of these bodies are exactly si- milar to those by which the corresponding ethylic bodies are formed. Ethylic dimethacetone carbonate is a colourless, slightly oleaginous liquid, possessing a peculiar penetrating and pleasant odour, and a sharp burning taste. It is scarcely at all soluble in water, but readily so in alcohol and ether. Its specific gravity is '9913 at 16° C. It boils constantly at 184° C., and distils unchanged. A determination of its vapour-density gave the number 5 -3 6, the above formula requiring 5 -4 5. Its remaining properties very closely resemble those of ethylic diethacetone carbonate. Boiled with baryta-water, it gives barium carbonate and dimethylated acetone, f C Me H2 \CMeO Dimethylated acetone is a colourless, transparent and very mobile liquid, possessing a pleasant odour, reminding at the same time of parsley and ace- tone. Its specific gravity is '8099 at 13° C., and it boils at 930>5 C. Its vapour-density is 2'92, theory requiring 2*97. Dimethylated acetone closely resembles its ethylic homologue in all its chemical properties ; like diethylated acetone, it is oxidized with difficulty, and does not very readily form a crystalline compound with bisulphite of soda — differing in the latter respect markedly from its isomer, ethylated acetone, and also from me- thylated acetone described below. Ethylic dimethacetone carbonate and ethylic methacetone carbonate boil at the same temperature, arid cannot therefore be separated by rectification ; but we have prepared and examined the ketone from the second of these bodies ; viz. methylated acetone, which has the formula J C Me H2 \CMeO Methylated acetone is best obtained in a state of purity by combining it with bisulphite of soda, pressing the beautiful crystalline compound so formed between folds of blotting-paper to remove traces of dimethylated acetone, exposing it over sulphuric acid in vacuo, and then regenerating the methylated acetone by distillation with aqueous potash. The liquid so ob- tained, after drying over quicklime and rectification, gave analytical results corresponding with the above formula. Methylated acetone is a colourless, transparent and very mobile liquid, possessing an odour like chloroform, but more pungent. It is tolerably soluble in water, and more than slightly so in a saturated solution of com- mon salt. Its specific gravity is '8125 at 13° C. It boils at 81° C., and its vapour-density is 2*52, the above formula requiring 2'49. Methylated acetone is identical with the ethyl-acetyl obtained by Freund * in acting upon chloride of acetyl with zinc ethyl. Methylated acetone forms a splendidly crystalline compound with bisulphite of soda, and in its other chemical properties so closely resembles ethylated acetone as to require no further description. It retains alcohol with such tenacity as to render its separation from that liquid by washing and treatment with chloride of cal- * Ann. Ch. Pharm., vol. cxviii. p. 1. 464 Mr. Schorlemrner on the Hydrocarbons [Nov. 16, cium almost impossible. This separation, however, is readily effected by bisulphite of soda. III. Action of Sodium and Amyl Iodide upon Acetic Ether, For this reaction the compounds of sodium derived from acetic ether were prepared as before, and were then submitted to the action of amylic iodide for several hours at the boiling-point of the mixture. When the sodium had all become converted into iodide, water was added and the su- pernatant liquid decanted. We reserve a complete description of this liquid for our next communication, and will here confine ourselves to the separa- tion from it of oenanthylic acid, which was obtained as follows : — The crude product, after drying over chloride of calcium, was submitted to rec- tification, and the portion boiling between 170° and 190° C. collected apart and decomposed by ebullition with alcoholic potash. By this treatment we destroyed any ethylic amylacetone carbonate and ethylic diamylacetone carbonate that were present, and obtained a potash-salt of an acid derived from acetic acid by the substitution of one atom of amyl for one of hydrogen. The potash-salt thus obtained was distilled with excess of sulphuric acid diluted with a large quantity of water. Upon the distillate there floated an oily acid, possessing an odour resembling oenanthylic acid. This acid was converted into an ammonia-salt, from which a silver-salt was prepared by precipitation. After being well washed with cold water, this salt yielded numbers on analysis closely corresponding with the formula of amylacetate or cenanthylate of silver : OAg We have also examined the barium-salt, which is an amorphous soapy substance. Dried at 100° C., '2715 grm. gave '1599 grm. of barium sul- phate, corresponding to 34-62 per cent, of barium. Barium oenanthylate contains 34 '09 per cent, of barium. We believe amylacetic acid to be identical with cenanthylic acid. The concluding portion of the paper is devoted to a discussion of the theoretical bearings of the reactions above described, and to the investi- gation of the internal architecture of the synthetically prepared ethers, acids, and ketones. II. " Researches on the Hydrocarbons of the Series CH H2)!+2." — No. II. By C. SCHORLEMMER, Esq., Assistant in the Labora- tory of Owens College, Manchester. Communicated by Prof. H. E. ROSCOE. Received July 20, 1865. From my experiments communicated to the Royal Society on the 6th of April, 1865, I concluded that the question, whether only one series of hydrocarbons of the general formula Crt Hzw+s exists, or whether this 1865.] of the Series CnlI2R+y 465 series exhibits cases of absolute isomerism, can only be definitely decided by obtaining from different sources perfectly pure hydrocarbons, having the same composition. But unfortunately only a few of the hydro- carbons can be obtained perfectly pure, and still fewer of these possessing the same composition can be derived from different sources. This is seen by a glance at the following Table, containing those alcohol-radicals and hydrides which have been obtained with certainty in a pure state. Boiling-points, Boiling-points. C0 H8 Methyl. Hydride of ethyl. G; H10 Ethyl. C3 H]2 0 Hydride of Amyl .... 30 C6 Hu Ethyl-butyl 62 Hydride of hexyl * . . 69'5 C7 H16 Ethyl-amyl 90 Hydride of heptyl f . . 99 C8 H18 Butyl 108 C9 H00 Butyl-amyl 132 C10H2"2 Amyl ..." 158 C12 H2C Hexyl (caproyl) 202 For the purpose of examining the question of the identity or the isomerism of these hydrocarbons, I selected methyl-hexyl and hydride of heptyl, obtained from azelaic acid, comparing the properties of these bodies with ethyl-amyl, as described in my last communication. (1) Methyl-hexyl. Methyl-hexyl (methyl-caproyl) has already been prepared by \Vurtz by the electrolysis of a mixture of acetate and oenanthylate of potas- sium, but he has obtained it in a small quantity only, and in a very impure state J. I adopted the same method, and am able to confirm all that Wurtz has stated. Although I employed several ounces of cenanthy- late of potassium, only a very inconsiderable quantity of an aromatic oil was obtained, which, in order to isolate the hydrocarbon C7 H,6, was first distilled with concentrated sulphuric acid, by the action of which sulphu- rous acid was evolved and a black charry matter separated out. The oily distillate was well washed and further purified by means of nitric acid, caustic potash, and sodium, as described in my former papers, and then the small quantity of methyl-hexyl separated by fractional distillation from hexyl, C]2H26, which latter hydrocarbon is formed in by far the greatest proportion. Methyl-hexyl boils at 89°-92°C., and has the specific gravity 0-6/89 at 1 9° C. The analysis gave the following numbers : — 0-2002 substance gave 0'6150 carbonic acid and 0'2900 water. Calculated. Found. C7 84 83-78 H10 _16 16-14 100 99-92 * Dale, Journ. Chem. Soc. New Ser. ii. p. 258. t Ibid. I Ann. de Chim. et de Phys. 3 scr, xliv. 296. 466 Mr. Schorlemmer on the Hydrocarbons [Nov. 16, The quantity which I obtained was only sufficient for determining the boiling-point and the specific gravity, both of which nearly coincide with those of ethyl-amyl ; and although I could not investigate its reactions, I believe that these also will agree with those of ethyl-amyl, so that the two hydrocarbons appear to be identical. (2) Hydride of Heptyl from Azelaic Acid. By C. SCHORLEMMER and R. S. DALE, B.A. One of us has shown that by heating a mixture of azelaic acid and caustic baryta to a dull red heat, an aromatic liquid is obtained, which chiefly consists of the hydrocarbon C7 H16. By oxidizing castor-oil with nitric acid on a large scale, one pound of pure azelaic acid was prepared, which yielded about one ounce of a hydrocarbon boiling between 95° and 100°. Subjected to fractional distillation, a small quantity of hydride of hexyl from the suberic acid, which still adhered to the azelaic acid, was separated, and now the liquid boiled constantly at 100°'5 C. (corrected). The sp. gr. at 20°'5 C. was found to be 0'6640. The determination of its vapour-density gave the following results : — Balloon + air .................. 7'5660 Temperature of air .............. 16°-5 Balloon and vapour .............. 7'7830 Temperature on sealing .......... 140° Capacity of balloon .............. 1 15'5 cub. centims. Vapour density calculated. Found. 3-46 3-63 This hydrocarbon is very easily attacked by chlorine, the chloride C7 H15 Cl being chiefly formed, together with a small quantity of higher chlorinated products. The chloride boils at 151°-lo3° C., and has the specific gravity 0'8/37 at 18°'5. It is a colourless liquid, smelling exactly like the chloride ob- tained from ethyl-amyl. 0-3045 substance gave 0'3165 chloride of silver and 0'0045 of metallic silver. Calculated. Found. 26-40 per cent. Cl 26*20 per cent Cl By heating this chloride with acetic acid and acetate of potassium in sealed tubes, heptylene and acetate of heptyl are formed. This decompo- sition goes on much quicker than in the case of the chloride from ethyl- amyl ; and the proportions of the substances formed also differ, as only a very small quantity of heptylene is produced, and the chief product con- sists of the acetate, whilst the chlorides from ethyl-amyl and from petro- leum yield these two substances in about equal quantities. The heptylene boils at 95°-97°, and has the specific gravity 07026 at The faint garlic-like smell is identical with that of the heptylene de- scribed in my last paper. 1865.] of the Series Cnll2n+2. 467 0-1952 substance gave 0-6130 carbonic acid and 0-2510 water. Calculated. Found. CT 84 85-7 85-65 Hu _1£ 14-3 14-28 8 100-0 99-93 The acetate also has the same pear-like smell as the acetate from ethyl- amyl. It boils at 180°-182°, and has the specific gravity of 0*8605 at 16°. 0-2446 substance gave 0-6135 carbonic acid and 0-2540 water. Calculated. Found. C9 108 68-35 68-40 H]8 18 11-39 11-53 02 32 20-26 158 100-00 From the acetate the alcohol was prepared by heating with a concen- trated solution of caustic potash. Dried over caustic baryta, the alcohol boiled at 164°-167°. The specific gravity at 19°-5 = 0'8286. Its odour cannot be distinguished from that of the alcohol from ethyl- amyl. By oxidizing it with chromic acid, first the odour of cenanthol is per- ceived, and then an oily acid is obtained, which by its smell, as well as the analysis of its silver-salt, was recognized as cenanthylic acid. 0-1205 of the silver-salt obtained by saturating the rectified acid distillate with carbonate of silver, gave 0'0551 of metallic silver, or 45*72 per cent., the formula C7 H13 AgO2 requiring 45'57 per cent. Ag. The annexed Table gives the boiling-points and specific gravities of the hydrocarbons C7 H1G of different origin, and their derivatives. From these data, as well as from the experiments detailed in this and in my former papers, it appears that we meet here with examples of absolute isomerism, viz. compounds having the same percentage composition and the same con- stitutional formula (A. Crum Brown), but differing from each other in their physical properties. This is not only the case with the hydro- carbons, but also, in a greater or less degree, with their derivatives. Ethyl-amyl and hydride of heptyl from azelaic acid, as well as the corre- sponding chlorides, were obtained in as pure a state as possible, and in pretty large quantities ; and although only small quantities of the acetate, alcohol, and olefine from the hydride were at our disposition, yet the greatest care was taken to obtain them pure, and all determination of the boiling-points and specific gravities were carried out under the same circumstances, the same thermometer always being used, so that they may be fairly compared with each other. 468 Mr. Schorlemmer on the Hydrocarbons [Nov. 16, Heptyl compounds derived from 1. 2. 3. 4. Methyl- Petroleum. Ethyl-amyl. Azelaic acid, hexyl. r IT ("Boil.-point 90°-92°(98-99 °) 90°-91° 100°'5 89°-92° 7 16 1 Sp. gravity 0-7148 at 15° 0-6795 at 20° 0-6840 at 20°-5 0-6789 at 19° CrH14 f Boil.-point \ Sp. gravity 95°-97° 0-7383 at 17°-5 93°-95° 0-7060 at 12°-5 95°-97° 0-7026 at 19°-5 _ C7H13C1 f Boil.-point "I Sp. gravity 148°-150° 0-8965 at 19° 146°-148° 0-8780 at 18°-5 0-8737 at 18°-5 C7H100 f BoiL-point \ Sp. gravity 164°-165° 0-8479 at 16° 163°-165° 0-8291 at 13°-5 164°-167° 0-8286 at 19°-5 cl^b} n f Boil.-point U LSp. gravity 0-8865 at 190° 178°-180° 0-8707 at 16°-5 180°-] 82° 0-8605 at 16° C. M. Warren has lately published * an investigation on the hydro- carbons contained in the American petroleum, which he isolated according to a new method of fractional condensation. He states that the petro- leum contains two series of the hydrocarbons CmH2n+2, the isomeric pairs of which show a difference in their boiling-points of 7°-8°. Some of the results which I have formerly obtained tend to confirm this view. Frankland, Wurtz, Pelouze, and Cahours found 30° as the boiling-point of hydride of amyl ; the hydrocarbons of the same composition, which I isolated from the light oils obtained from Cannel coal, boils constantly between 39° and 40°. The hydride of heptyl obtained from the same source boiled at 98°-99°, and the same hydrocarbon I found in American petroleum, whilst Pelouze and Cahours give 92°-94° as the boiling-point ; and in my last communication I have quoted some experiments made by Mr. Wright, who found that from that part of American petroleum which boils between 95°-100° a considerable quantity of a hydrocarbon, C7 H16, may be obtained which boils constantly at 90°-92°. These latter hydro- carbons and their derivatives show, even after repeated rectification, higher specific gravities than the isomeric alcohol -radicals and the hydrocarbons from azelaic acid. Thus it appears that bodies showing a purely physical isomerism are as numerous in the marsh-gas family as in the case of the terpines, C10 H16. In order to complete this investigation, I intended to study in the same manner the hydrocarbons CB Hu, namely hydride of hexyl from suberic acid, methyl-amyl, and, if possible, ethyl-butyl ; but this intention could not be carried out, as I could not succeed in preparing methyl-amyl. This hydrocarbon appears not to be formed by any of the methods which are employed to prepare the so-called mixed alcohol-radicals. A mixture of the iodides of methyl and amyl is exceedingly slowly attacked by sodium. The boiling-point of the mixture is below the fusing-point of sodium, and the metal soon becomes coated with a hard crust of iodide of sodium. I * Mem. American Academy, New Series, vol. ix. p. 156. 1865.] of the Series Ctt H2rt+2. 469 added, therefore, a sufficient quantity of pure amyl to raise the boiling point, but even the sodium in the fused state acts very slowly, a consider- able quantity of gaseous products being evolved. After the mixture had been heated for a week, large quantities of the iodides were still present, and after destroying these by strong nitric acid, the remaining hydrocarbon was found to be pure amyl. No better results were obtained by adding anhydrous ether to tho mixture. The action in the cold is exceedingly slow ; heated in sealed tubes, the iodides are soon decomposed ; but besides gaseous products, only amylj and not a trace of a mixed radical, is formed. Besides hydride of heptyl, other products are formed by the action of caustic baryta upon azelaic acid. Of those only one could be obtained in a pure state. If the aromatic liquid which is first obtained is distilled with water, hydride of heptyl chiefly distils, and a brown oily liquid re- mains behind, which, after cooling, solidifies to a crystalline mass con- taining a brown aromatic oil which may be removed from the crystals by pressing between blotting-paper. The solid substance is repeatedly re- crystallized from hot diluted alcohol, in which the still adhering oil is very slightly soluble. The pure substance is thus obtained in small colourless needles, which are grouped in tufts. It is odourless and tasteless, very soluble in ether and in alcohol, insoluble in water, melts between 41° and 42°, solidifies again at 40°, and distils between 283°-285° (not corrected) without decomposition. The following analysis shows that it has the formula C« H2». 0-2480 substance gave 0*7800 carbonic acid and 0-3215 water. Calculated. Found. C» 85-7 85-77 ' H2)l 14-3 14-40 100-0 100-17 The quantity obtained was not sufficient to determine the vapour-density. If this olefine is suspended in water and bromine added, not in excess, the two substances combine readily to a colourless oily liquid, the odour of which resembles bibromide of ethylene. It cannot be distilled without decomposition, and appears even to be decomposed by a diluted solution of caustic soda, as a small portion thus treated in order to remove an excess of bromine changed its odour completely. By an unfortunate accident the whole of the bromide was lost, -with the exception of the portion treated with caustic soda. This was washed with water, dissolved in ether, and the ethereal solution dried with chloride of calcium. After evaporating the ether and drying the remaining small quantity of heavy yellow oil over sulphuric acid under the air-pump, only just sufficient was left to determine the bromine. 0-1500 gave 0-0736 of bromide of silver, and 0*0102 of metallic silver, corresponding to 25*8 per cent, of bromine. From the boiling point of the olefine it appears that its molecular for- 470 Messrs. V. Harcourt and Esson on the [Nov. 1C, mula is most likely CZ6 H32 ; and if bromine forms the bibromide, C16 H32 Br2, from wbich by the action of caustic soda H Br is abstracted, the com- pound analyzed would be C16 H31 Br, which formula requires 26'4 per cent, of bromine, whilst the analysis gave 25*8 per cent. ; the hydrocarbon would then be an isomer of cetene. III. " On the Laws of Connexion between the conditions of a chemical Change and its Amount/' By A. VERNON HARCOURT and W. ESSON. Communicated by Sir B. C. BRODIE, Bart., F.R.S. Received September 5, 1865. (Abstract.) The amount of a chemical change under any conditions which allow of its completion, depends ultimately upon the amount of that one of the substances partaking in it which is present in the smallest proportional quantity. But if the change be arrested before any one of the reagents is exhausted, its amount depends upon the conditions under which it has oc- curred. These conditions, in the simplest cases, are the quantity of the several reagents, their temperature, and the time during which they have been in contact. The laws of connexion between these conditions of a che- mical change and its amount are the subject of an investigation upon which the authors have entered. An account of the first stage of this investiga- tion is contained in the present paper. Although every chemical change is undoubtedly governed by certain general laws relating to the conditions under which it occurs, the number of cases in which the investigation of these laws is possible is extremely limited. For it is requisite both that the amount of change should be readily estimated, and also that all the conditions affecting it should be sus- ceptible of measurement and of such independent variations as must be made in order to determine the separate influence of each. The first reaction chosen for investigation was that of permanganic acid upon oxalic acid. It is well known that when a solution of potassic per- manganate is added to a solution containing an excess of oxalic acid and sulphuric acid, a change takes place which in its final result is represented by the following equation : — K2Mn2O8+3H2SO4+5H2C204=K2SO4 + 2MnS04+10C02+8H20. This reaction occurs at the ordinary temperature ; it is thus comparatively easy to keep the temperature of the solution absolutely constant during its progress. It occupies, under a due arrangement of other conditions, a con- venient interval of time, and can be started and terminated at a given moment. The reagents are readily obtained in a state of purity, and can be accurately divided and measured as liquids. Lastly, no other condition besides those named affects the result : when each of these is fixed, the amount of change observed in successive experiments is always the same. Nevertheless this reaction, as appeared in the course of its investigation, is 1865.] Laws of Connexion, fyc. 471 not well adapted to the purpose in view. It is not chemically simple. More than one change occurs under the circumstances of the experiment, and the equation above written represents only a net result. But the ex- amination of a second and simpler reaction in which the authors are at present engaged, has confirmed an explanation which had already suggested itself to them of the results of this series of experiments, and thus they are now enabled to present these results together with a theory which explains and is supported by them. The effect of varying the amount of each of the reagents and the dura- tion of the action was successively investigated. The remaining condition of temperature was not made the subject of experiment, owing to the dis- covery of the complex nature of the chemical change. A series of Tables contain the numerical results of these experiments. The principal com- plication arises from a secondary reaction which takes place between per- manganic acid and the manganous salt formed by its reduction. It became necessary, in consequence of this action, to include manganous sulphate among the reagents the effect of whose variation was to be determined. The general method of experimenting was briefly as follows : — Measured quantities of the standard solutions of oxalic acid, sulphuric acid, and man- ganous sulphate were mixed with a measured quantity of water and the whole brought to a temperature of 16° C. A measured quantity of a stan- dard solution of potassic permanganate was added, and the time of the addition noted. Throughout the course of the action the temperature, observed by means of a thermometer passing into the fluid, was kept rigo- rously constant. When the required interval had elapsed, an excess of potassic iodide was thrown in, and the liberated iodine, which furnishes an exact measure of the residual permanganic acid or manganic oxide, esti- mated by means of a standard solution of sodic hyposulphite. The amount of chemical change occurring in any given time with any given amounts of the several reagents can thus be determined. 1 . Variation of Sulphuric Acid. — Each experiment of this series was allowed to proceed for four minutes. Oxalic acid and potassic permanga- nate were employed in the proportions in which they act one upon another. The quantity of sulphuric acid was varied from the proportional quantity up to seven times that amount. A regular increase in the amount of che- mical change within the allotted time occurs with each increment of sul- phuric acid. The relation of these quantities, which formed the subject of many series of experiments, is, however, of a complex character. Two or three reactions, it is shown, occur simultaneously, and each of these is influenced by the acidity of the solution. 2. Variation of Manganous Sulphate. — At the ordinary temperature in a dilute and feebly acid solution, permanganic acid acts very slowly upon oxalic acid, but the presence of a manganous salt, formed by its reduction or previously added, causes a great acceleration. This acceleration is shown to reach a maximum when three molecules of manganous sulphate are taken to one of permanganate. By the reaction of these quantities man- 472 Messrs. V. Harcourt and Esson on the [Nov. 16, gauic binoxide is formed according to the equation K2 Mna 08 + 3 MnS04 + 2 H2 O = K2 SO4 + 2 H2 S04 + 5 MnOa. 3. Variation of Oxalic Acid. — The results obtaiued in this series of experiments are at first sight paradoxical. The quantity of permanganate reduced in three minutes, which was the time allowed to each experiment, increases with the proportion of oxalic acid up to a certain point ; it then diminishes until another point is reached, after which further additions of oxalic acid produce again a very gradual acceleration. The result is the same whether only oxalic acid, potassic permanganate and manganous sul- phate are taken, or whether sulphuric acid is added to these. The maxi- mum action occurs with five molecules of oxalic acid and one of perman- ganate, that is with proportional quantities. The second and constant minimum is nearly attained with ten molecules of oxalic acid. Probably the manganic binoxide formed by the reaction of manganous sulphate and potassic permanganate combines with an excess of oxalic acid to form a compound whose decomposition proceeds more slowly than the action of free binoxide upon it. The conditions of the minimum action may be thus represented : — 1. MnO2 + 2H2C,04=MnC408 + 2H20. 2. MnC4Oa=MnC2O4 + 2CO2. There is found in the first instance a clear brown solution, the colour of which slowly fades. 4. Variation of the Time. — If it were possible for all other conditions of a chemical change to remain constant, if, for example, the substances reacting could be added in proportion as they disappeared, and those formed either were without influence or could be removed, the effect of a variation of time might be confidently predicted. In such a case the total amount of chemical change would be directly proportional to the duration of the action. But when one or more of the substances diminishes in quantity as the change proceeds, the relation is no longer of this simple cha- racter. Experiments upon this relation form the remaining and chief part of this inquiry. Each experiment of a series exactly resembled every other except in the time allowed to elapse beforo the action was interrupted. And thus each series may be regarded as exhibiting the course of a single experiment, and showing how much of the active substances still remain at any time from its commencement. In the earlier series the reagents were employed in proportional quanti- ties, and it was observed that for most of the determinations the product of the number expressing the duration of the action and of the number expressing the amonnt of active substance still remaining, is a constant quantity. The first stages of the action exhibit, however, a divergence from this law. This divergence is explained by reference to the simulta- neous occurrence of two gradual actions, that in which manganic binoxide is formed and that in which it is reduced. The inverse proportionality of the residue to the duration of the action when two substances present in 1865.] Laws of Connexion, $c. 473 proportional quantities are destroying one another, is shown to follow from a law the generality of which the authors hope to establish— namely, that the total amount of chemical change varies directly with the amount of each of the substances partaking in it. In the later series of experiments the necessary condition, that the ratio of the reagents should remain constant throughout the action, was fulfilled by taking all but one of them in great excess as compared with that one. Under these circumstances a single substance gradually disappears, all around it remaining unchanged ; and according to the law above enunci- ated, the total amount of change occurring at any moment is proportional to the quantity of substance then remaining. It is shown that if this be the case, the numbers representing the amounts of residue after equal in- tervals of time should form a series in geometric progression. This relation is actually exhibited by some of the experimental series ; but the greater number of them do not conform to it. The reason of this is to be found in the fact that more than one reaction occurs under the circumstances of these experiments, and that it is only possible to measure the total effect. Experiments upon the solution in which the gradual oxidation of oxalic acid has taken place are adduced to show that some other oxidized product besides carbonic acid is formed, and it is inferred that more than one agent takes part in its oxidation. Also the facility with which hydrated peroxide of manganese reacts with dilute sulphuric acid and manganous sulphate to form a solution of mangano-manganic sulphate renders it probable that this salt is produced in the experiment. With an excess of oxalic acid and manganous sulphate the red colour of potassic permanganate disappears as soon as this salt is added to the mixture. The formation of manganic bin- oxide appears to be instantaneous. It finds itself in presence of two sub- stances, both of which act gradually upon it — oxalic acid and manganous sulphate, the latter producing an intermediate oxide, probably the protoses- quioxide, which is also reducible by oxalic acid. It is possible that other oxides besides these may be formed ; but it is almost certain, from the experimental results, that the action is not more simple than this. At the end of each expe- riment both" or all of these oxides are alike instantaneously reduced by hydri- odic acid and thus measured conjointly. Finally it is shown that an equation may be constructed embodying this hypothesis, and that all the series of experimental numbers may be expressed by equations of this form. The paper concludes with a mathematical discussion, by Mr. Esson, of various points in the theory of this action. An outline of his statement is here appended. When a single substance is undergoing chemical transformation under constant conditions, it is shown by experiment that the law of connexion between y, the quantity of substance remaining unchanged, and x, the time during which the change has been proceeding, is y=aax ; where a is the quantity of substance present at the beginning of the change, and a a con- VOL. XIV. 2 N 474 On the Laws of Connexion, fyc. [Nov. 16, stant, which depends upon the conditions under which the change takes place. From this equation is derived dy ctydz, which expresses the fact that the amount of change varies directly with the time and with the quan- tity of substance. Cases of complex chemical change can be investigated by the application of this general law. When two substances are reacting in proportional quantities, the amount of change is proportional to the amount of each, and the equation for determining the character of the reaction is dy = < y. By varying continuously one of the conditions of the reaction, it is possible to obtain in succession values of a and y, such that a is first >• y, and then = y, and finally < y ; and thus these three forms of curves may occur in an investigation on the effect of varying one of the conditions of a reaction of this kind. 1865.] Note, by Dr. Davy, on Birds. 475 Supplementary Note to Dr. Davy's Paper on Birds ; received November 25, 18G5. Mention is made in the paper referred to of the comparatively low tem- perature of certain birds. Another example of the same kind occurs in the goose ; in two instances I have found its temperature in recto 104°, and in a third 103°'5. The trials were made in November; the geese had not previously been confined, were about seven months old, fully feathered (few birds have a warmer clothing), and the weather at the time was moderate ; the temperature of the open air between 40° and 50° Fahr. Notice is also taken of a bird, the grouse, not remarkable for power of flight, having air in its femora as well as in its humeri. I have since found another example of the same kind in the pheasant, a bird even of feebler flight; in no instance, and I have examined several specimens, have I detected marrow in either of these bones. In reference to the statement implying that those bones of birds which contain air in their adult state, in an earlier stage contain marrow, later observations have led me to infer that, instead of marrow, these bones have their canals impacted with blood-vessels, which in process of the bird's growth shrink and are absorbed. November 23, 1865. Lieut.-General SABINE, President, in the Chair. In compliance with the Statutes, notice was given from the Chair of the ensuing Anniversary Meeting, and the list of Council and Officers proposed for election was read as follows : — President. — Lieut.-General Edward Sabine, R.A., D.C.L., LL.D. Treasurer. —William Allen Miller, M.D., LL.D. f William Sharpey, M.D., LL.D. \ George Gabriel Stokes, Esq., M.A., D.C.L. Foreign Secretary. — Professor William Hallows Miller, M.A. Other Members of the Council. — John Frederic Bateman, Esq. ; Lionel Smith Beale, Esq., M.B. ; William Bowman, Esq. ; Commander F. J. Owen Evans, R.N. ; Edward Frankland, Esq., Ph.D. ; Francis Galton, Esq.; John Peter Gassiot, Esq. ; John Edward Gray, Esq., Ph.D. ; Thomas Archer Hirst, Esq., Ph.D. ; Sir Henry Holland, Bart., M.D., D.C.L. ; William Odling, Esq., M.B. ; Sir John Rennie, Knt. ; Prof. Warington W. Smyth ; William Spottiswoode, Esq., M.A. ; Paul E. Count de Strzlecki, C.B., D.C.L. ; Vice-Chancellor Sir W. P. Wood, D.C.L. Dr. Robert M'Donnell was admitted into the Society. Pursuant to notice given at the last Meeting, The Right Honourable Charles Pelham Villiers was proposed for immediate ballot. VOL. XIV. 2 O 476 Prof. Tyndall on Calorescence. [Nov. 23 The proposal having been seconded, the ballot was taken, and Mr Villiers was declared duly elected a Fellow of the Society. Mr. Villiers was afterwards admitted into the Society. 1 The following communications were read : — I. "On Calorescence." By JOHN TYNDALL, F.R.S. Received October 20, 1865. (Abstract.) The paper is divided into ten short sections. In the 1st the experiments of Sir William Herschel and of Prof. Miiller on the sun's radiation are described. In the 2nd are given a series of measurements which show the distribution of heat in the spectrum of the electric light. In the 3rd section is described a mode of filtering the composite radiation of an in- tensely luminous source so as to detach the luminous from the non-lumi- nous portion of the emission. The ratio of the visible to the invisible radiation determined in this way is compared and found coincident with the results of prismatic analysis. The eminent fitness of a combination of iodine and bisulphide of carbon as a ray-filter is illustrated, and in the 4th section experiments with other substances are described ; various effects obtained in the earlier experiments on the invisible rays being mentioned. In the 5th section the absolutely invisible character of the radiation is established ; it is also proved that no extra-violet rays are to be found at the obscure focus. Numerous experiments on combustion produced by invisible rays are also described in the 5th section. The 6th section deals with the subject of calorescence, or the conversion of obscure radiant heat into light. In section 7 various modes of experimenting are described by which the danger incident to the use of so inflammable a body as the bisulphide of carbon may be avoided. In the 8th section are described experiments on the invisible radiation of the lime-light and of the sun. In the 9th section the effect obtained by exposing papers of different colours at the dark focus are mentioned ; while the 1 Oth and concluding section, deals with the calorescence obtainable from rays transmitted by glasses of various kinds. II. " Notice of the Surface of the Sun." By JOHN PHILLIPS, M.A. LL.D., F.R.S., &c., Professor of Geology in the University of Oxford. Received October 27th, 1865. It appears desirable, as a first step to a right theory of the condition of the sun's surface, that the appearances which it presents should be re- corded in some systematic way. Photographs will suffice for the distribu- tion of the spots, but careful eye-drawings must be appealed to in evi- dence of the form, arrangement, and intestine motions of the parts of those spots, and eye-drawings with measures are the only means of recording accurately the dotted, areolar, granular, crested, and other arrangements 1865.] Prof. Phillips on the Surface of the Sun. 477 which under the general title of " porosity " have been recognized over the whole face of the sun. Descriptions cannot be complete, but, what is more, they may be, and probably often are, misleading — words which call up right ideas of things often fail very much when required to perform the same function for new objects not well understood. With this con- viction in my mind, I have requested the Royal Society to accept a few drawings representing features on the sun's face as they appear to me looking through a telescope of known dimensions, and used in a certain way. If observers would send sketches made at the telescope, showing what they see, or think they see, — not finished paintings to illustrate hypothetical ideas, — these sketches, by gradual accumulation and com- parison, would at last furnish evidence by which even a great theory might be brought to a satisfactory test. Therefore it is that I presume to offer to the Royal Society some additional sketches of the "porosity" of the sun, as seen in good observing weather in this month of October*. The whole surface of the sun, as seen on the 24th and 25th, appeared quite free from any dark patches large enough to be called spots— offering in this respect a singular contrast with its aspect on the 1 7th, when the large doubly nucleated spot, of which I sent a sketch a few days since, was so conspicuous near the (apparent) right edgef. On this apparently even and marble-like surface, a power of 50, with the full aperture of 6 inches, made manifest the existence of the porosity at every point, from the centre to near the edge, the distinctness being greatest over all the middle part of the area. By applying successively powers of 75, 100, 135, and 180, it was easy to observe the general effect, and the particular features of diversity. The clock-rate being regulated exactly, any particular part of the disk might be kept continually under view ; and to increase the distinctness of the object, or rather the comfort of the observer in looking at it, the field was contracted by diaphragms to one-half or one-third of the usual diameter. The great obstacle to a strict observation of any small selected part of the sun's disk is unsteadiness of the head, a circumstance troublesome to portrait-photographers, but more injurious to astronomers. I believe this kind of error to be one of the elements of personal equation, and that it can sometimes only be cured by allowing the observer to take hold of the moving telescope. This, thanks to Mr. Cooke's solid construction, can be safely done. The sketches now presented relate only to the appearances presented to one observer, with the precautions stated ; to what degree they are affected by " personal equation" remains to be proved by comparison with others, and I hope better drawings. * Drawings made on a former occasion, and presented to the Royal Society, may be referred to for comparison. (See Plate XII. fig. 6.) f Telescope furnished with diagonal glass, the rays reflected to the West. By this arrangement the usual reversal of the object in every direction becomes limited to the vertical direction. 2o2 478 Prof. Phillips on the Surface of the Sun. [Nov. 23, PL XII. fig. 1 represents a part of the surface under a low power (75), which is carefully moved out of focus inwards and outwards. Under these conditions, the soft undefined mottling which it shows catches the eye, and appears clearly to be caused by parts not differing in structure from the more shadowy spaces between them, except by there being less effect of shadow points and lines on the parts which are relatively lighter. Here and there apparently dark specks appear, either in the darker tracts or on the lighter parts ; and there are specks of all degrees of darkness, as well as lines of greater or less distinctness. PI. XII. fig. 2 is offered as a careful attempt to copy a definite tract, still employing a low power (75), and using every means to get the focus exactly. When this is accomplished, and the eye placed as close as possible to the eyepiece, the appearances can be sketched as well as an artist can picture a tree with its leaves, a heap of broken stones, or some dissected and areo- lated clouds. They can be sketched, but certainly not well or truly, without patient attention, and eyes and head in a good state. Here the texture appears to be areolar, with much irregularity in the shapes, but no great inequality of size. Dots of extremely small dimensions, sometimes quite black, appear singly or in pairs in the centres of several areolse. PI. XII. fig. 3. Another sketch, under the same conditions, but employ- ing powers of 135 and (rarely) 180. In this part of the disk dots, occa- sionally running together into a complicated short tract, may be seen, not specially conformed to the areolar structure, but in some places crossing it, and elsewhere scattered about it. The number of short irregular discon- tinuous lines which occur mixed with dots is very great ; none of them appear to be regularly curved or regularly straight, but seem to be intervals merely between more enlightened parts. It does not seem to me that dots of greater darkness usually appear at the intersections or terminations of these fissure-like objects. PI. XII. fig. 4, is intended to convey the impression arising from a close study of one small space quite definite in character and marked by distinct small dots, one elongated in the middle part of a subpentagonal space, around which other less regular areolse were gathered. After much atten- tion, it appeared to me that the boundaries of this rude pentagon were in part broken up into irregular short loops and dots ; and though the obser- vation was difficult, I am not afraid to trust it. This selected space is drawn on a larger scale, but it was not seen with higher powers than No. 3. PI. XII. fig. 5 shows a curious areola with a black central dot, and three parallel markings on the boundary. PI. XII. fig. 6, a sketch made in April 1864, is introduced for com- parison, and especially for the softly luminous mottling of the surface. I shall be very glad to be informed whether what is here said agrees or not with the observations of other persons, made with other instruments. 1865.] Prof. Phillips— Notice of a Spot on the Sun. 479 Supplementary Note, Nov. 25, 1865* The spot to which the above notices refer has been made the subject of careful observations by M. Chacornac, who has issued interesting descrip- tions and drawings of it from October 7 to October 16. The Rev. Mr. Hewlett has also scrutinized the same object, and prepared drawings to October 17, the day when my first sketch was made. Thus we have for this spot observations through one rotation and a half, and we may perhaps have the pleasure of welcoming it again in a new form. — J. P. III. " Notice of a Spot on the Sun, observed at intervals during one Rotation." By JOHN PHILLIPS, M.A., LL.D., F.R.S., Professor of Geology in the University of Oxford. With Drawings. Re- ceived November 15, 1865. On the 17th of October, 1865, at 2 P.M. the spot referred to had tra- versed a great portion of its arc, and was approaching the limb. It showed two large unequal umbrae, and in each of them a blacker nucleus. Between them were several small dark dots, partially coalescent. The edges of the umbrse were very irregular. In the smaller umbra two bright dots. Above the larger umbra (which appeared to the right in the telescope) was an exceptionally bright band, traversed by two dark threads ending in dark dots. This band crossed a part of the umbra, like a bridge, but itself was there traversed by a small bar. Four bright patches lay in the continu- ation of this facula toward the prolonged upper (apparently) extremity of the penumbra, which was itself more luminous than other penumbral parts. The penumbra had broken edges, and an interior mottling of small brighter and darker spaces directed variously toward the umbrse. The granulated surface of the sun with soft gleaming facular ridges was conspicuously seen, and tracts of darkly dotted surface were seen beyond each extremity and on one side (PI. X. fig. 1). Nov. 4, 9.45. — The spot had now returned by rotation, and was very distinctly seen amidst far extended clouds of bright faculae, though reduced to less than half its former dimensions. It retained the two umbral tracts 5 but it was now the left-hand tract which was the larger. Being about 15° from the lirnb, the general figure was oval, as usual ; the umbrae were of irregular figure, the larger one cut into by bright branches from the inter- umbral space. Dark dots amidst the faculae on the border (PI. X. fig. 2). Nov. 6, 9.45. — The spot had reached about 45° from the edge, and appeared less elliptical, and otherwise changed in aspect. The large um- bra was much dissected by bright streams, and the smaller one had assumed a distinctly tripartite shape. The edges of the penumbra appeared rugged. Many small spots and dark dots towards the edge of the disk (PI. X. fig. 3) Nov. 11, 9.45. — The spot had now passed the central meridian, and was greatly altered, and almost cut into two parts by a bright facular mass, passing between the umbrse. The larger of these is now in a pentagonal 480 Prof. Phillips — Notice of a Spot on the Sun. [Nov. 23, form, and has a bright central speck, with a rather obscure narrow prolon- gation. The smaller umbra is tripartite, and has small gleaming points in it. Several black dots in the surrounding surface, amidst faculae, areolse, and other structures very distinctly seen for a great part of this day with good definition (PL XL fig. 4). Nov. 13, 9.45. — Very great change in general figure and in the several parts of the spot. The larger spot is now cut in twain ; the smaller spot is reduced to two dots, surrounded by a large bright space. The spot is now about 36° from the limb (PI. XI. fig. 5). Nov. 15. — The spot is very near the edge, and of course almost elliptical in outline (PL XI. fig. 6). The faculse which accompany it are seen on a smaller scale in PL XI. fig. 7. The woodcut shows the apparent places of the spot at the several dates mentioned. EXPLANATION OF THE FIGURES IN PLATES X., XI., XII. PI. X. fig. 1. Appearance of spot near the edge of the disk before passing off. 2. Spot after reappearance, within the opposite edge of the disk. 3. The same farther on the disk. PI. XI. fig. 4. The same after passing the centre of the disk. 5. The same advancing toward the edge. 6. The same very near the edge. 7. The same surrounded by faculaj. This figure is drawn on a smaller scale than the others. PI. XII. figs. 1, 2, 3, 4, 5. Sketches taken in October 1865. 6. Sketched in April 1864. 1865.] Anniversary Meeting. 481 November 30, 1865. ANNIVERSARY MEETING. Lieut.-General SABINE, President, in the Chair. Mr. Bowman, on the part of the Auditors of the Treasurer's Accounts appointed by the Society, reported that the total receipts during the last year, including a balance of .£683 14*. Id. carried from the preceding year, amounted to ^64882 0*. Id. ; and that the total expenditure in the same period, including 36905 invested in the Funds, amounted to 365001 18*. 1 Id., leaving a balance of £ 135 7*. lOd. due to the Bankers, and £15 9s. i the hands of the Treasurer. The thanks of the Society were voted to the Treasurer and Auditors. The Secretary read the following Lists : — Fellows deceased since the last Anniversary. Royal. His Imperial and Royal Highness the Archduke Maximilian of Austria. On the Home List. John George Appold, Esq. George Boole, Esq. George William Frederick Howard, Earl of Carlisle, K.G. Samuel Hunter Christie, M.A. Joseph Dickinson, M.D. Hugh Falconer, M.A., M.D. Rear- Admiral Robert FitzRoy. Renjamin Gompertz, Esq. Richard Dugard Grainger, Esq. Woronzow Greig, Esq. Sir Benjamin Heywood, Bart. Sir William Jackson Hooker, K.H., LL.D. Rev. George Hunt, M.A. WilliamThomas HornerFoxStrang- ways, Earl of Ilchester, M.A. John Lindley, Esq., Ph.D. Sir John W. Lubbock, Bart., M.A. James Heywood Markland, D.C.L. Sir John Maxwell, Bart. James B. Neilson, Esq. Algernon Percy, Duke of Northum- berland, K.G. Benjamin Oliveira, Esq. Henry John Temple, Viscount Palmerston, K.G. Thomas Joseph Pettigrew, Esq. Sir John Richardson, C.B. Sir Robert Schomburgk. Robert William Sievier, Esq. Admiral William Henry Smyth, K.S.F. Henry Herbert Southey, M.D. Rev. Robert Walker, M.A. Thomas Williams, M.D. On the Foreign List. Johann Franz Encke. | Adolph Theodor Kupffer. Withdrawn. William Hopkins, M.A., LL.D. Defaulter. William Bird Herapath, M.D. 482 Anniversary Meeting. [Nov. 30, Fellows elected since the last Anniversary. On the Home List. George Harley, M.D. Fleeming Jenkin, Esq. William Huggins, Esq. Sir F. Leopold M'Clintock, Com- modore. Robert M'Donnell, M.D. William Kitchen Parker, Esq. Alfred Tennyson, Esq., D.C.L. George Henry Kendrick Thwaites, Esq. Lieut.-Col. James Thomas Walker, R.E. The Right Hon. Charles Pelham Villiers. Dufferin and Claneboye, Frederick Temple Blackwood] Lord, ILP., K.C.B. Donoughmore, Richard John Hely Hutchinson, Earl of. Turner, The Right Hon. Sir George James, Lord Justice. H.R.H. Louis Philippe d'Orle'ans, Count of Paris. The Hon. James Cockle, M.A. Rev. William Rutter Dawes. Archibald Geikie, Esq. George Gore, Esq. Robert Grant, Esq., M.A. George Robert Gray, Esq. The PRESIDENT then addressed the Society as follows : — GENTLEMEN, IN my last year's Address I informed you of the steps which had been taken, with the approval of the Council, to obtain the concurrence of Her Majesty's Government in the printing and publication of the Catalogue of the Titles of the Scientific Memoirs contained in Scientific Periodicals in all languages, from the commencement of the present century to the end of 1863, the manuscript of which had been prepared under the direction and superintendence of the President and Council, and the cost defrayed from the funds of the Society. Her Majesty's Government having been pleased to accede to the proposition that had been then made to them, the Serial Catalogue, as originally proposed for the Society's Library, is now in progress of rearrangement in alphabetical order according to author's names, to be followed by an alphabetical Index according to subjects. The preliminary questions regarding the type, and'the form and size of the pages, having been discussed and agreed upon with the authorities of the Stationery Office, the first portion of the manuscript, containing the titles of all memoirs having the letter A as the first letter of the author's name, has been prepared, and is now placed in the printer's hands, so that the printing may be forthwith commenced. In the meantime the endeavours to render the work more complete have not been relaxed ; the number of titles, which in my last year's Address was stated to exceed 180,000, has been since extended to 213,000 ; and will continue to be augmented whilst the printing is in progress. It is proposed that all titles which should not be in time to be entered under their respective alphabetical heads shall be included in a supplementary 1865.] President's Address. 483 volume, which shall also comprise the titles of memoirs which must be regarded as Anonymous, having been published without the author's name. The original Serial Catalogue prepared in manuscript for the use of the Fellows of the Society still remains in the Library ; and it is with great satisfaction that I am able to add that the Library itself already possesses the Transactions, Journals, and other periodical works in which two-thirds of the 213,000 titles already collected for the Catalogue are contained; and that every endeavour is making to render the Library as complete as possible in this important branch of scientific literature. The total expenses hitherto incurred in the preparation of the Catalogue amount to <£l 626 ; and to this a small annual addition will be required until the printing and publication shall have been completed. The Fellows of the Royal Society, and those especially who are in- terested in the progress of Sidereal Astronomy, will hear with pleasure that the communications, passing through Her Majesty's principal Secre- tary of State for the Colonies, between Sir Henry Barkly, K.C.B., F.R.S., Governor of the Colony of Victoria, and the President and Council of the Royal Society, regarding'the establishment at Melbourne of a telescope of great optical power for the observation of the Nebulae and multiple stars of the southern hemisphere, have led to a vote which has passed the Legislature of Victoria of .£5000 for a suitable telescope, to be con- structed under the superintendence of the President and Council of the Royal Society. In the Anniversary Address in 1862, and again in that of 1863, I availed myself of the opportunities then afforded of making known to the Fellows the progress of the communications which at each of those dates had taken place between the Government of Victoria, the authorities of the Melbourne Observatory, and the Royal Society ; and I have now the satisfaction of laying before you the following letter, re- ceived on the 23rd of last month from Professor Wilson, Honorary Secre- tary of the Board of Visitors of the Melbourne Observatory : — " The University, Melbourne. Aug. 21, 1865. "My DEAR SIR, " It is with very great satisfaction that 1 forward to you the following resolutions of the Board of Visitors adopted on the loth inst. : — " 1. That the President of the Royal Society of London be informed that the Legislature of Victoria has voted the sum of .£5000 for the purchase of an equatorial telescope, one half of which sum has been already remitted to the Crown Agents in England, and placed at the dis- posal of Major Pasley, of the Royal Engineers, for the purpose ; and that the Government has placed the correspondence connected with it in the hands of the Board of Visitors. " 2. That the President and Council of the Royal Society be requested to give the Board of Visitors the benefit of their assistance in selecting a maker, settling the contract, and superintending the construction of the 484 Anniversary Meeting. [Nov. 30, telescope, so as best to carry out the recommendations contained in the Report of the Royal Society to the Duke of Newcastle, 18th December 1862. " 3. That Major Pasley be requested to place himself in communication with the President and Council of the Royal Society, and, after ascertaining their views, to enter into such contract as will most effectually carry them out. " I enclose also a copy of a letter received from the Treasury, on which the foregoing resolutions are based, and a copy of the letter which I send to Major Pasley by this mail. " The great interest which you have shown in this matter leads the Board of Visitors to count confidently on your further assistance in bring- ing it to a successful conclusion. The request contained in the second resolution is not intended to imply that in the opinion of the Board any further discussion as to the form of telescope or the maker is necessary. The Board thinks, and I believe that it is also your opinion, that the dis- cussion which has already taken place has settled that question, and that Mr. Grubb's proposal should be adopted. This is not distinctly expressed in the resolution, because Mr. Grubb's name is not mentioned in the Report of the Royal Society, and because the Board desires to leave you free in the event of anything having happened to Mr. Grubb, or of any discovery having been made which would tend to modify your opinion. " In any case the Board, bearing in mind the great length of time that has elapsed since the proposal for a telescope was first made, and having now received authority from the Government to act in the matter, is de- sirous of securing the completion of the telescope at the earliest possible time consistent with the highest attainable perfection in the instrument ; and considers that this end will be most effectually secured by leaving you quite free to act in the matter, and trusting to you to secure the co- operation of those eminent practical astronomers whose names you men- tioned as willing to superintend the work during its execution. " Mr. Grubb's last estimate is £4600 for the telescope complete ; and this, I believe, covers everything, including the erection in Ireland for a trial. " The sum voted is £5000, and the balance, £400, will be available for a spectroscope and for a photographic apparatus adapted to the telescope, and will still probably leave sufficient to pay the freight to Melbourne. As these two adjuncts will not occupy long in making, it will probably be desirable not to commence them till the telescope proper is approaching completion, so that the latest improvements may be introduced into them. " Trusting to your earnestness to induce you to undertake the great amount of trouble we are imposing upon you, " I remain, my dear Sir, " Very faithfully yours, " W. P. WILSON, " Hon. Sec. to the Board of Visitors." " Major-General Sabine, R.A., Pres. R.S." 1865.] President's Address. 485 To the information contained in this letter I have now the satisfaction of being able to add that since its receipt Mr. Grubb has signified his readiness to proceed in the construction of a telescope corresponding to the specification contained in his letter to Dr. Robinson of Dec. 3, 1 863, printed in the second portion of the correspondence respecting the Southern Telescope, — the execution to be under the supervision of the Earl of Rosse, Dr. Robinson, and Mr. Warren De la Rue, who, on their parts, have accepted the responsibilities of superintendence. The contract between the Crown Agent for Victoria and Mr. Grubb is in process of execu- tion, and in eighteen months from its date we may hope that the telescope will be in readiness to be embarked for Melbourne, where in the meantime preparations will be made for its reception and mounting. The selection of an Astronomer fitted by education and acquirements to be entrusted with its use at Melbourne, and who may be willing to devote his entire energies to the cultivation of the splendid field which will be open to him, must be the next anxious and important duty devolving upon the Mel- bourne authorities. If in its execution they should require any assistance from the Royal Society, such assistance will assuredly be most readily given. The arrangements connected with this subject being so far advanced, I have thought it desirable to place on record a consecutive statement of the steps by which they have been brought to their present stage ; and I have done this in the form of a Note (Note A)*, to avoid trespassing unneces- sarily upon your present attention. The welcome intelligence has been received from Colonel "Walker, F.R..S., Superintendent of the Trigonometrical Survey of India, of the safe arrival in that country of the Pendulums prepared for the experiments which it is proposed to make at the principal stations of the survey, and of the vacuum-apparatus in which the pendulums are to be vibrated. As it has been proposed to make the Kew Observatory the Base Station of the important observations which may be made with these instruments in many parts of India, a full and very careful series of Base observations were made with them at Kew before their departure for India. These have been printed in the Proceedings of the Royal Society in the present year in the form of a communication from Messrs. Balfour Stewart and Loewy. In the course of the last Session an important paper was communicated to the Society, and has been since printed in the Philosophical Transactions for 1865, Art. V., entitled « On the Magnetic Character of the Armour- plated Ships of the Royal Navy, and on the Effect on the Compass of par- ticular arrangements of Iron in a Ship," by Staff-Commander Frederick John Evans, R.N., F.R.S., Superintendent of the Compass Department of Her Majesty's Navy, and Archibald Smith, Esq., F.R.S. In the course of the reading of this paper, and in the discussion which * See note A, p. 503. 486 Anniversary Meeting. [Nov. 30, followed it, the absence of any proper provision for the instruction or guidance of the builders, fitters, and navigators of the ships of our mer- cantile marine was strongly dwelt upon. It is well known that the number of iron ships recently constructed greatly exceeds that of wood-built ships. In such vessels iron is now used, not only in the construction of the hull, but in decks, deck-houses, masts, rigging, and many other parts of the ship, for which wood was till recently used. The consequence has been a great increase in the amount of the deviation of the compass, increased diffi- culty in finding a suitable place for the compass, and an increased neces- sity for, and difficulty in, applying to the deviation either mechanical or tabular corrections. Many recent losses of iron steamers have taken place, in which there is reason to believe that compass-error occasioned the loss. In most of these, however, from the want of any record of the magnetic state of the ship, of the amount of the original deviation, and of the mode of correction — and from the investigations into the causes of the loss having been conducted by persons uninformed or not interested in the science, and who are neces- sarily incompetent therefore either to elicit the facts from which a judg- ment can be formed, or to form a judgment on those facts which are elicited — no certain conclusion as to the cause of the loss can be arrived at. The investigations are, however, sufficient to show the want of a better and more uniform system of compass-correction in the mercantile marine, and of more knowledge of the subject on the part of those who are entrusted with the fitting and navigation of these ships. - Acting in conformity with the opinions expressed in the discussion which followed the reading of the paper by Commander Evans and Mr. Smith, and availing themselves of the counsel of thosewho are justly regarded as possessing the greatest practical experience on such subjects in this or any other country, the President and Council addressed a letter to the President of the Board of Trade, bringing under his consideration a sub- ject which they have reason to believe is of pressing importance, requiring that measures of a more stringent and effective character should be taken in the direction already followed by Her Majesty's Government in such legislative enactments as those contained in the Merchant Shipping Act of 1854 ; and, impelled by a strong conviction of the impending danger, they have ventured to suggest the expediency of steps being taken for the mer- cantile marine similar in character to those which have been found to work so successfully in the Compass Department of the Royal Navy. The lamented decease of the late Admiral FitzRoy induced a desire on the part of the Board of Trade to review the past proceedings and pre- sent state of the department of that Board which had been placed under Admiral FitzRoy's direction. Adverting to the fact that at the forma- tion of that Department the Board of Trade had requested the opinion of the Royal Society as to what might then be considered the great 1865.J President's Address. 487 desiderata in Meteorological Science, and had received in reply a letter from the President and Council (dated February 22, 1855) containing recommendations which were eventually adopted as the basis of the pro- ceedings of the Meteorological Department of the Board of Trade, the Board was now desirous of being informed to what extent those objects had been fulfilled by what had already been accomplished, and whether the objects which had been so specified were still considered as important for the interests of science and navigation as they were then considered. The Board of Trade were also desirous of obtaining an opinion from the Royal Society regarding the Forecasts of Weather and the Storm Warn- ings which had not been included in the original recommendations of the Royal Society, but had originated with Admiral FitzRoy himself and had formed a considerable part of the duties of the Meteorological Depart- ment since 1859. To enable the President and Council to form a judgment on the ques- tions referred to them, the Board of Trade supplied them with the following documents : — 1. Admiral FitzRoy's Report to the Board of Trade, dated May 1862. 2. A Report by Mr. Babington (Admiral FitzRoy's first assistant) on the method adopted in the department with regard to forecasts and storm- warnings. 3. A return to the House of Commons, dated April 13, 1864, present- ing a comparison of the probable force of the wind as indicated by the signals in the year from April 1, 1863, to March 31, 1864, and its actual state as reported in the three days following the exhibition of the signals. 4. A manuscript return, furnished by Mr. Babington, having the same object for the year from April 1, 1864, to March 31, 1865. The first of these documents contained the opinions of the Shipmasters at several ports on our coasts, officially requested and given, in regard to the practical value which they attached to the storm-warnings. Of these replies, by far the greater number were decidedly favourable, three only out of fifty-six being decidedly unfavourable. The date of the Report containing them was May 1862 ; and the two subsequent Reports, dated respectively in 1864 and 1865, exhibited in comparison a marked improve- ment in successive years. Upon the authority of those statements, and viewing the system of forecasting which Admiral FitzRoy had instituted simply (as described by himself) as "an experimental process," based on the knowledge conveyed by Telegraph of the actual state of the winds and weather and other meteorological phenomena within a specified area, and on a comparison of these with the telegrams of the preceding days, so as to obtain inferences as to the probable changes in the succeeding days — taking into account also the evidence supplied of the improvement in the forecasts of each year compared with those of the preceding year — the Pre- sident and Council were of opinion that it was not unreasonable to antici- pate that the system, so far at least as regarded the storm-warnings, if 488 Anniversary Meeting. [Nov. 30, continued, might receive still further improvement ; and that possibly the best arrangement at the present time would be that this branch of the duties of the office should continue as at present, and be carried on under the direction of Mr. Babington, by whom it had been virtually superin- tended for several months past. With reference to those branches of inquiry which had been originally suggested by the Royal Society in the letter of the President and Council of February 22nd, 1855, the reply, as might reasonably be expected, was of a more decided character. The most prominent amongst the objects recommended in that letter was the collection and coordination of facts bearing on what may perhaps not improperly be termed Oceanic Sta- tistics,— viz. all such facts as are required to enable a correct knowledge to be formed of Currents of the Ocean, their direction, extent, velocity, and the temperature of the water relatively to the ordinary ocean temperature in the same latitude, together with the variations in all these respects which currents experience in diiferent parts of the year and in different parts of their course. These, as well as the facts connected with the great persistent barometric elevations and depressions which we know to exist in several oceanic localities, leading to a knowledge of their causes, as well as of their influence on circumstances affecting navigation, were noticed in the letter of February 1855 as inquiries well deserving the attention of a country possessing such extensive maritime facilities and interests as ours, and as likely to form a suitable contribution on our part to the general system of meteorological inquiry which had then recently been adopted by the principal continental states in Europe and America. It was learnt from Mr. Babington that much had been done by Ad- miral FitzRoy in the three or four years succeeding the establishment of his office (and before the subject of storm-warnings had engrossed the greater part of his thoughts), in directing the attention of many of the commanders of our merchant ships to the collection of suitable data, and in improving their habits of observation and of record. The logs of such vessels, we were informed, constitute at present a large collection of documents existing in the office of the Board of Trade, partially examined, and their contents partially classified. A full and careful examination of these for the purpose of ascertaining the amount and value of their contents was our first recommendation, to be combined with a considera- tion of the most fitting mode in which the information they might be found to contain may be made available for public use. Such an exami- nation may also be expected to lead to improvements in the instructions which have been issued to our merchant seamen, who have doubtless be- come more competent to conduct, and even to extend, the observations for these and similar purposes, than when the system was first introduced. Those amongst us who have read with the attention it deserves the admirable paper in which Captain Henry Toynbee has enriched our Proceedings in the past year with the results of his five Indian voyages, will not doubt the 1865.] President's Address. 489 competency or the disposition that may exist amongst our merchant seamen to collect materials of the highest value for the investigations which the President and Council originally recommended ; and we can entertain no doubt that, whatever may prove to be the amount and value of the ma- terials already collected, they will form but a small contribution towards that general embodiment of the statistics of the ocean which the great in- crease of our commercial activity makes of pressing importance, and which may be expected to shorten materially the passages between distant ports. The Board of Trade were also desirous to know whether the Eoyal Society has any recommendations to make with reference to what may be called "Meteorology proper," viz., meteorological observations to be made on land, in addition to the marine observations which were so strongly urged in the letter of the President and Council of February 1855. The reason why the advantages to be derived from a well-directed system of maritime observations was more particularly pressed on that occasion was, that neither the instruments nor the modes of observation suitable for a well-organized, general, and efficient system of land meteorology had been then prepared. The circumstances which constituted the difficulty in this respect were well stated by Lieut. Maury in a letter addressed to the United States Government, dated November 6, 1852, subsequently trans- mitted by the American minister to the Earl of Clarendon, and printed in the papers preceding the Brussels conference, which were presented to the House of Lords in February 1853. This difficultv no longer exists, having been wholly obviated by the self-recording system of observation, for which the necessary instruments have been devised and brought into use at the Kew Observatory. The President and Council have had therefore no hesitation in expressing the opinion that systematic meteorological observations at a few selected land stations in the British Islands are desirable, in addition to the marine meteorological observations, in order to complete a suitable contribution from this country to the meteorological observations now in progress in the principal states of Europe and America, under the authority of their respective Governments. A few stations, say six, distributed at nearly equal distances in a meridional direction from the south of England to the north of Scotland, furnished with self-recording instruments supplied from and duly verified at one of the stations regarded as a central station, and exhibiting a continuous record of the temperature, pressure, electric and hygrometric state of the atmosphere, and the direction and force of the wind, might perhaps be sufficient to supply an authoritative knowledge of those peculiarities in the meteorology of our country which would be viewed as of the most importance to other countries, and would at the same time form authentic points of reference for the use of our own meteorologists. The scientific progress of meteorology from this time forward requires in- deed such continuous records — first, for the sake of the knowledge which they alone can effectively supply, and next for the comparison with the 490 Anniversary Meeting. [Nov. 30, results of independent observation not continuous. The actual photograms, or other mechanical representations, transmitted periodically by post to the central station might be made to constitute a lithographed page for each day in the year, comprehending the phenomena at all the six stations — each separate curve admitting of exact measurement from its own base-line, the precise value of which might in every case be specified. The President and Council have added a suggestion that the Observatory of the British Association at Kew might, with much propriety and public advantage, be adopted as the central meteorological station. It already possesses the principal self-recording instruments, and the greater part of these have been in constant use there for many months. There would be no difficulty in obtaining similar instruments for the affiliated meteoro- logical stations, and in arranging for their verification and comparison with the Kew standards, as well as in giving to those into whose hands they may be placed, such instructions as may ensure uniformity of operation. You are aware that Royal Princes, Foreign as well as British, who signify their desire to enter the Society, and are proposed accordingly, are under- stood to be entitled to immediate ballot. On a late occasion, however, it was found that, according to the strict letter of the statutes, the head and repre- sentative of a Royal House might be inadmissible by privileged election, whilst members of the same family of inferior rank were entitled to it. His Royal Highness the Count of Paris having expressed a desire to join our body, it appeared on referring to the Statutes, that although he is the son of the late Duke of Orleans and hereditary representative of the late King of the French, yet, inasmuch as his father had not been a "sovereign prince," the Society was precluded from showing him a courtesy which it may extend to other members of his family who look up to him as the head of their house. The Council, believing that the Society would desire to see this anomaly corrected, took, after due deliberation, the prescribed steps for amending the Statute ; and being advised that the usage of Her Majesty's Court would afford a suitable criterion of rank applicable to the case, introduced words extending the privilege in question to " any foreign Prince who is received by Her Majesty as Imperial Highness or Royal Highness." The unanimous election of the Count of Paris under the amended Statute may, I think, be taken as a ratification of the act of the Council. I am glad to avail myself of this opportunity of stating that the reduc- tion of the automatic records of the bifilar magnetometer at Kew during the seven years from 1858 to 1864 inclusive has now been completed, so far as to make known the relative amount of magnetic disturbance in each of those years. The results are shown in a note (B)*, by which it will be seen that 1859 was a year of decided maximum, the aggregate disturb- ances in that year being considerably greater than in 1858, and dimi- * See note B, p. 512. 1865.] President's Address. 491 nishing progressively from 1859 to 1863-1864: in 1863 and 1864 the amount of disturbance was nearly identical, and was only about one-third of the amount in 1859. From the general aspect of the photographic traces in the present year (1865), there appears reason to believe that the epoch of minimum is now passed. If this be so, the years 1863-64 will have been the fourth return of the epoch of minimum since 1823-24 (Arago's Meteorological Observations, English translation, Editor's Note, pages 355 to 357)> thus confirming the coincidence with the decennial variation of the sun-spots discovered by Schwabe. Those who regard with interest the progressive establishment of the theory which assigns a cosmical origin to the Terrestrial Magnetic Varia- tions, will have noticed the remarkable, but not altogether unanticipated, testimony borne to the decennial variation by the annual values of the magnetic Inclination at Toronto in the years from 1853 to 1864, in the volume recently published by Mr. Kingston, Superintendent of that Ob- servatory. The general effect of the disturbances of the Inclination at Toronto is to increase what would otherwise be the amount of that ele- ment ; therefore, if the disturbances have a decennial period, the absolute values of the Inclination (if observed with sufficient delicacy) ought to show in their annual means a corresponding decennial variation, of which the minimum should coincide with the year of minimum disturbance, and the maximum with the year of maximum disturbance. I have placed in a note (C)* the annual values derived in each case from the regular monthly determinations, commencing with 1853, and ending with 1864, taken from the publication referred to, whereby it will be seen that an actual variation does exist such as I have indicated, 1853 being a minimum and 1859 a maximum ; the increasing progression being uninterrupted from 1853 to 1859, and the decreasing progression uninterrupted from 1859 to 1864, the date of the latest published results. It was in the year 1853 that the Toronto Observatoiy was transferred to the provincial authorities, and was placed by them under the direction of Mr. Kingston. The Inclinometer employed is the same which was described in a paper in the Philosophical Transactions for 1850, Art. IX., entitled "On the Means adopted in the British Colonial Magnetic Ob- servatories for determining the Absolute Values, Secular Changes, and Annual Variations of the Terrestrial Magnetic Elements ;" and the as- sistants by whom the observations were made were the same persons who had performed the same duties when the Observatory was under, the direction of Officers of the Artillery. The results are ar valuable exemplifi- cation of the accuracy attainable when proper attention is paid to the selection of the instruments, and to the employment of careful and skilful observers. Such evidence is of more than ordinary interest at the present time, when such institutions are rapidly increasing. We have recently learned by a despatch from Sir II. Barkly, Governor of * See note C, p. 513. VOL. XIV. 2 P 492 Anniversary Meeting. [Nov. 30, Mauritius, to the Secretary of State for the Colonies, a copy of which has been transmitted to the Royal Society by Mr. Cardwell, that arrangements have been made and funds provided for a magnetical and meteorological observatory in that colony, on the model of the Kew Observatory ; and that Professor Meldrum, who has been appointed its superintendent, may be expected immediately at Kew to receive the instruments which have been prepared by Mr. Balfour Stewart, and to make himself acquainted with the details both of instruments and methods in use at that observatory. We have also reason to hope that the example thus set at Mauritius will shortly be followed at Melbourne and at Bombay. A summary of the results arrived at in discussing the Solar Autographs taken at the Kew Observatory with the Photoheliograph belonging to the Royal Society has appeared in the ' Proceedings ; ' and the Fellows have thus been made acquainted, in a general way, with the conclusions which have been based on the observations so obtained. The state of the atmo- sphere permitting, pictures of the sun are taken daily by Miss Beckley, daughter of the resident mechanical assistant ; and these are as regularly measured and discussed by Dr. Loewy. In this way has been accumulated a vast mass of materials on which to found conjectures as to the nature of the physical forces operating at the surface of the sun ; and, taking these materials as a basis, Messrs. De la Rue, Stewart, and Loewy have drawn the conclusions enunciated in their several papers on solar physics. It is, however, by no means improbable that other investigators, could they ob- tain access to the same full and complete details of the observations and measurements, would succeed in evolving other and most important theories of solar activity, and thus that our knowledge of the subject might be greatly advanced. It is moreover evident that in a method of observa- tion so new, and in a subject so intricate, the minutest fact can hardly be dismissed as insignificant, seeing that, whatever its present apparent isola- tion, it may hereafter be shown to stand connected with an important series of facts, towards a right theory of which it may indeed furnish im- portant aid. It has therefore to be considered in what way the publica- tion of these voluminous details can be best effected. Pending this, how- ever, I am glad to state that the authors above-named have themselves determined to print in detail their first paper, and that a sufficient number of copies will be placed at the disposal of the Society for distribution among the Fellows. The amount of spotted area is being measured ; and the elements of the sun's rotation will be calculated from the spots. Those of the Fellows who are interested in the trial of gun-cotton as a propellant, will be glad to learn that its employment as a charge for the \Vhitworth and Eufield Rifles is progressing favourably. By a mode of construction of the cartridge ingeniously devised to control the too great rapidity of combustion, the cotton is found to command, without injury to 1865.] President's Address. 493 the rifle, a range fully equal to that of powder, and, in experiments at the School of Musketry at Hythe, under the superintendence of Major-General Hay, has made excellent shooting, producing diagrams at 1000 yards, hardly, if at all, inferior to those obtained from the best small-bore rifles of the day. These diagrams were obtained with a Whitworth- Rifle : in the first, 10 consecutive shots were fired at 1000 yards, with a mean radial deviation of T65 foot; in the second, 9 consecutive shots at 1000 yards, giving a mean radial deviation of 2'02 feet. And in the third, 20 consecutive shots were fired at 1000 yards, giving a mean radial deviation of 2-43 feet. The charge in all cases was 25 grains of gun-cotton, the angle varying from 3° to 3° 3'. The cartridges with which these shots were fired were made by hand : the defect of cartridges so made is obvious, viz., that they may not be strictly uniform. But this is an inconvenience remediable by the employ- ment of very simple machinery. In preliminary trials above 2000 rounds have been fired out of one and the same rifle, without occasioning the slightest injury to the piece. The advantages of the cotton charges were manifest in the diminution of recoil and smoke, and in the entire absence of fouling. The demand for cotton charges for sporting-purposes has become very considerable since the shooting-season commenced, and they are under- stood to have given very general satisfaction. It is not unreasonable to anticipate that the principles of construction of the cartridges which have proved so successful in the adaptation to small arms, may eventually, with suitable modifications, make cotton available for iron ordnance, as a substitute, in a greater or less degree, for powder, which is far more dangerous in manufacture and storage. As far as has been yet tried, the cotton is found to keep perfectly well for any length of time submerged in distilled water. I proceed to the award of the Medals : — The Council has awarded the Copley Medal to M. Michel Chasles, For. Mem. U.S., for his Historical and Original Researches in Pure Geometry. The historical and original researches of Chasles extend over a period of about forty years. Throughout this time he has devoted his energies, with a constancy of purpose rarely equalled, to the restoration and ex- tension of those purely geometrical methods which, bequeathed to us from antiquity, had their growth arrested during the middle ages, and their utility temporarily eclipsed by the brilliant discovery of coordinate geometry by Descartes. In his well-known ' History of the Origin and Development of Geometrical Methods,' published in 1837 and crowned by the Academy of Brussels, Chasles thus expresses what has proved to be the leading object of his life's labours : — " I propose to show, so far as my feeble means will permit, that in a nuiltitude of questions the doctrines of pure geometry most frequently present to us that easy and natural path which, penetrating to the very 494 Anniversary Meeting. [Nov. 30, origin of truths, brings us into actual contact with each individual truth, and at the same time reveals to us the mysterious chain by which all are connected." The elaborate work here quoted* is unique of its kind ; it is our highest authority on all matters connected with the history of geometry, of which science it carefully traces the development from the time of Thales and Py- thagoras, down to the earlier part of the present century. Although pro- fessing to be an aperru merely, it nevertheless represents a vast amount of historical research, and is moreover enriched by copious notes containing the results of important original investigations. In the year 1846 the foundation of a chair of modern geometry was de- cided upon by the Faculty of Sciences at Paris, and Chasles was at once chosen to supply a demand which his own researches had in a great measure created. Thus commenced that personal influence on the younger geo- meters of his country which still continues, and is traceable in all their productions. Another result of this appointment, by which geometers of all nations have greatly profited, was the publication, in 1852, of his 'Trea- tise on the Higher Geometry '•(•, — a work in which the three fundamental principles of pure geometry are, for the first time, fully and systematically expounded. These principles embrace the modern theories of anharmonic ratios, of homographic divisions and pencils, and of geometric involution. An anharmonic ratio is in reality a ratio of two ratios, the latter having reference to two pairs of segments determined by any four points of a line. On one peculiar property of this ratio — that of its remaining unaltered by projection — all modern geometry may be said to be founded. Homographic divisions consist of two rows of points, in the same straight line or in different ones, which so correspond that the anharmonic ratio of any four points of one row is equal to that of the corresponding points of the other row. Finally, two homographic rows, in the same straight line, are said to form an* involution when to any point whatever of that line one and the same point corresponds, no matter to which of the two rows the first point may be conceived to belong. Usually there are two points in such an involution, each of which coincides with its own corresponding point ; by a mere accident of position, however, the actual existence of these double points may be destroyed, whilst all other properties of the involution remain intact. In this contingency originated a mode of speech of the greatest utility in geometry. The double points are said to be real in the one case, and imaginary in the other. For the undisguised and philosophic introduction of imaginary points and lines into pure geometry we are chiefly indebted to Chasles. * Aperfu historique sur 1'origine et le developpement des mcthodes en Geometric, particulierement de celles qui se rapportent a la Geometric Moderne ; stiivi d'un Memoirc de Geometric sur deux principes generaux de la science, la dualite et riiomograpliie. Bruxelles, 1837. German translation by Dr. SShncke; Halle, 1837. t Traite de Geometric Superieurc. Paris, 1852. 1865.] President's Address. 495 The term anharmonic ratio, now universally employed, is due to Chaslcs ; the ratio itself, however, appears to have been known to Pappus, the eminent Alexandrian geometer of the fourth century. Chasles, indeed, has shown that this ratio probably constituted an essential feature of those three famous books on Porisms, which Euclid is known to have written, but of whose nature vague indications merely have been transmitted to us in the mathematical collections of Pappus. Robert Simson of Glasgow, the well-known translator of Euclid's ' Elements,' was the first who satis- factorily solved the enigma concerning the real nature of Porisms, and he also succeeded in partially restoring the three lost books. Chasles, however, was the first to restore them completely ; and this he has done in a work* which is admitted to be a valuable addition to the history of geometrical science, as well as a model of ingenious and philosophical divination. Chasles has contributed to the advancement of pure geometry, not only by means of the three complete works already alluded to, but also through the publication of numerous smaller memoirs. Of these the following, by no means the only important ones, demand a passing reference. The papers on " Stereographic Projections " converted a method ori- ginally devised for the construction of maps into a powerful instrument of geometrical transformation. Two able memoirs on " Cones of the Second Order" and on "Spherical Conies," thanks to the translation, published in 1841, by Dr. Graves of Trinity College, Dublin, had a direct influence on pure geometry in our own country. A paper " On the Corre- spondence between Variable Objects " furnished us with a principle of the greatest utility in all higher geometrical investigations. In several other memoirs the method of generating curves of higher orders by means of homographic pencils of curves of inferior orders is perfected, and new properties are thereby deduced of plane curves of the third and fourth orders. The theory of non-plane curves, especially those of the third and fourth orders, had its origin, for the most part, in Chasles's memoirs ; and the modern science of kinematics is indebted to him for two valuable papers on the finite and infinitesimal displacements of a Solid Body. The pro- blem of the attraction of Ellipsoids, rendered celebrated by the investiga- tions of Newton, Maclaurin, Ivory, Legendre, Lagrange, and Laplace, re- ceived from Chaslcs its first complete synthetical solution. In this problem, too, originated the conception of confocal surfaces of the second order, the theory of which he has since greatly perfected. The first volume of Chasles's fourth work (a Treatise on Conic Sections f) appeared during the present year: it is a sequel to his 'Higher Geometry ;' * Les trois livres dc Porismcs d'Euclide, retablie ponr la premiere fois, d'apres la notice et Ics lemraes dc Pappus, ct conformement au sentiment de R. Simson sur la forme des cnonces de ces propositions. Paris, 1860. t Traite dcs Sections Coniqucs, faisaiit suite au traito dc Geometric Snpcricurc. Paris, 1865. 496 Anniversary Meeting. [Nov. 30, and in it the three principles already alluded to find their most appropriate field of application. The second volume of this treatise is looked forward to with interest, as it will contain a full exposition of the admirable researches on conic sections wherewith Chasles has just crowned his labours. These researches, a brief account of which appeared during the past year in the pages of the ' Comptes Rendus,' have put us in possession of an entirely new method, the nature and utility of which may be rendered intelligible even to those who have not made modern geometry a subject of special study. For the determination or construction of the curves usually called conies, and of which the hyperbola, parabola, and ellipse are species, five conditions are requisite and, in general, sufficient. The nature of these five conditions may be such, however, as to admit of their being satisfied by more than one conic. For instance, although one conic only can be described through five given points, there exist two distinct conies, each of which passes through four given points, and touches a given line. Hence arises the important general question, How many conies are there capable of satisfying any five conditions whatever ? By the new method of Chasles we are enabled to answer this question, hitherto a difficult one, with great facility. Starting from the elementary cases where the five conditions are of the simplest possible kind, consisting solely of passages through points and contact with lines, he gradually replaces those conditions by more complex ones, and finally arrives at a simple symmetrical formula which fully answers the above question. Seeing how numerous are the questions in conies which may be ultimately reduced to the one here solved, we may, without exaggeration, assert that in this single formula a great part of the entire theory of conies is virtually condensed. The method has been aptly termed by its eminent discoverer a method of geometrical substitution. It involves the consideration of the properties of a system of conies (infinite in number) satisfyingybwr common conditions. Such a system is for the first time defined in a manner closely analogous to that in which curves are distinguished into orders and classes. We merely require to know, first, how many conies of the system pass through an arbitrarily assumed point, and, secondly, how many of them touch any assumed line. These two numbers or characteristics, as they are termed, being once found, all the properties of the system of conies are thereby expressible. For instance, the sum of twice the first characteristic and three times the second gives us the order of the curve upon which the vertices of every conic of the system are situated. This new method of characteristics has been already applied to curves of higher orders, as well as to surfaces ; and, considering the magnitude of the new fields of investigation thus opened out, it is probable that, as an instrument of purely geometrical research, the method of Chasles will bear comparison with any other discovery of the century. 1865.] President's Address. 497 PROFESSOR MILLER, M. Chasles being prevented from being present in person to receive the Medal which has been awarded to him, I have to request you as our Foreign Secretary to receive it for him, and to transmit it into his hands. It will assure him of the very high estimation in which his labours, in a branch of mathematical research which for more than a century has been little followed and little encouraged, are held in this country. The Council has awarded a Royal Medal to Joseph Prestwich, Esq., F.R.S., for his numerous and valuable Contributions to Geological Science, and more especially for his papers published in the Philosophical Transac- tions, on the general question of the Excavation of River Valleys ; and on the Superficial Deposits in France and England, in which the Works of Man are associated with the Remains of Extinct Animals. It is now not less than sixteen years since the Geological Society awarded to Mr. Prestwich the "Wollaston Medal, the highest honour in their gift, for the researches and discoveries he had then made ; and it may be said without disparagement to the services he had then rendered to geology, that the works he has since completed and published greatly outweigh in amount and value what he had achieved in 1849. Before that time his writings comprised memoirs both on the palaeozoic and tertiary strata : — one on the Old Red Sandstone strata containing ichthyolites, and on some beds of the glacial period at Gamrie; and another, a very elaborate one, on the coal strata of Coalbrook Dale, in which he explained in detail the structure of that coal-field, and the arrangement and distribution of the fossils throughout a long succession of the carboniferous strata. In the tertiary formations he introduced a considerable reform in the classification of the English series by proving, amongst other points, that the central division of the Bagshot Sands coincided in date with the "calcaire grossier" of the Paris Basin, instead of occupying, as was before supposed, a much higher place in the series. After 1849, continuing his researches on the English tertiary formations, he made two other important steps in the advance of our knowledge, viz., 1st, by showing that the clays of the Island of Sheppey, those of Barton, and those of Bracklesham, in Hampshire, instead of being all three contemporaneous, according to the then received opinions, were each due to a separate period, — an important rectification of the chronological order of the British tertiary formations ; and, 2nd, by pointing out that beneath the fluviatile beds of Woolwich, or that series commonly called the plastic clay and sands, there existed an older marine formation, for which he proposed the name of the Thanet Sands — a subdivision now generally recognized and adopted. By establishing the true position of this subdivision, a decided step was made towards filling up the wide gap which still divides the lowest of our Eocene strata from the Maastricht beds or upper part of the chalk. 498 Anniversary Meeting. [Nov. 30j After completing these and other papers, too many to enumerate here, Mr. Prestwich undertook the more difficult and complicated task of corre- lating the successive tertiary formations of England, France, and Belgium ; and communicated the results in Memoirs published in the Geological Society's ' Journal,' embodying the fruit of many years of travelling and much thought and study. In 1851 Mr. Prestwich published a separate work on the water-bearing strata around London, facilitating the subterranean search for water by giving actual measurements and probable estimates of the thickness of the chalk and other beds immediately above and below the chalk, and suggesting means of obtaining an additional supply of water for the metropolis. In 1859 Mr. Prestwich presented to the Royal Society a highly important memoir on the occurrence of flint-implements associated with the remains of animals of extinct species in France and England ; and another paper in 18G3, on the theoretical questions connected with the same subject. In these memoirs, as generally throughout all his writings, Mr. Prestwich has exhibited in a very marked degree a combination of unwearied labour and patience in the accumulation of facts, with a remarkable impartiality of judgment in the deduction of their bearing on the existing state of know- ledge,— a combination, the value of which cannot be too highly estimated. MR. PRF.STWICH, I present you with this Medal in testimony of the high sense entertained by the Council, and specially by those Members of the Council who are engaged in the same pursuits as yourself, of your laborious researches, and of the spirit in which they have been conducted, in the rectification of many important points in the geology of this and of neighbouring coun- tries, and in tracing out the facts of the occurrence of implements, the work of man's labour, in association with the remains of extinct animals. The Council has awarded a Royal Medal to Archibald Smith, Esq., F.R.S., for his papers in the Philosophical Transactions and elsewhere on the Magnetism of Ships. The irregularities to which ships' compasses are liable from the disturb- ing influence of the iron contained in the ship, originally noticed by the astronomer Wales in the voyages of Captain Cook, and subsequently by Flinders at the commencement of the present century, attained a magni- tude in the first of the polar voyages of discovery, viz. that of 1818, which forced on the attention of those who were responsible for the navigation of the vessels the indispensable necessity of meeting and surmounting the difficulties and dangers occasioned thereby. Having been attached to the two first of these expeditions to take charge of all matters of a scientific character, this duty devolved more especially on myself; and before the expedition of 1819 quitted the northern shores of Britain (those of the Shetland Islands), two leading characteristics of modern practice — the 1865.] President's Address. 499 establishment of a standard compass, in a fixed and suitable position, by which compass alone the ship's course should be directed and all bearings should be taken, and the formation of a table of deviations on the several points of the compass by the method now so universally practised of swinging the ship — were adopted in both the 'Isabella' and the 'Alex- ander.' The systematic character of the deviations, unprecedented in amount, which were experienced by these ships in subsequent parts of their voyage, attracted the attention of an eminent French geometrician, Poisson, who published, in 1824, two papers in the Memoirs of the French Institute, containing a mathematical theory of magnetical induction, with formulae in- volving coefficients to be determined by observation, expressing the action of the soft iron of a ship upon her compass — and, in a subsequent memoir, adapted the formulae to observations made on shipboard sufficient in num- ber to determine the coefficients in the particular case of the soft iron being symmetrically distributed on either side of the principal section of the ship. The application of these formulae was verified by deviations calculated for different positions in the high northern latitudes, where the absolute values of the magnetic elements, as well as the deviations of the compass on board, had been observed by the polar ships, the observed and calculated deviations showing a remarkable accordance. About twenty years after the date of the Arctic voyages, the system of compass-correction, which had been so successfully practised in the ships engaged in those voyages, was definitely adopted in the Royal Navy, on the recommendation of a committee appointed by the Admiralty, including among its members two of the officers who had served on these voyages, viz. the late Sir James Clark Ross and myself. At a somewhat later epoch the Magnetic Survey of the Antarctic regions brought into prominent view the importance and value of Poissori's theory. By far the greater part of the Survey having to be executed by daily ob- servation of the three magnetic elements on shipboard, it became desirable for the deduction of the results, that the fundamental equations of Pois- son's theory should receive such a modification as should adapt them to the form in which the data generally present themselves. This was the first great service which Mr. Smith rendered towards the correction of the irregularities occasioned by the magnetism of ships. Himself a mathe- matician of the first order, and possessing a remarkable facility (which is far from common) of so adapting truths of an abstruse character as to render them available to less highly trained intellects, he derived, at my request, from Poisson's fundamental equations, simple and practical for- mula} including the effects both of induced magnetism and of the more persistent magnetism produced in iron which has been hardened by any of the processes through which it has passed. These formulae supplied the means of a sufficiently exact calculation when the results of the Survey were finally brought together and coordinated. They were subsequently printed in the form of memoranda in the account of the Survey in the 500 Anniversary Meeting. [Nov. 30, ' Phil. Trans.' for 1843, 1844, and 1846. Instances occurred during the Survey, and are recorded in the account, in which (although these were not iron ships) the difference of the pointing of the compass on different courses exceeded 90° ; the differences almost entirely disappearing when Mr. Smith's formulse were applied. The assistance which, from motives of private friendship and scientific interest, Mr. Smith had rendered to myself was, from like motives, con- tinued to the two able officers who have successively occupied the post of Superintendent of the Compass Department of the Navy ; and the formula for correcting the deviation, which he had furnished to me, reduced to simple tabular forms, were published by the Admiralty in successive edi- tions for the use of the Royal Navy. As in the course of time the use of steam machinery, the weight of the armament of ships of war, and generally the use of iron in vessels increased more and more, the great and increasing inconveniences arising from compass-irregularities were more and more strongly felt, and pressed themselves on the attention of the Admiralty and of naval officers. An entire revision of the Admiralty Instructions became necessary. Mr. Smith's assistance was again freely given, and the result was the pub- lication of ' The Admiralty Manual for ascertaining and applying the De- viations of the Compass caused by the Iron in a Ship.' The mathematical part of this work, which is due to Mr. Smith, seems to exhaust the subject, and to reduce the processes by simple formulae and tabular and graphic methods to the greatest simplicity of which they are susceptible. Mr. Smith also joined with his fellow-labourer, Capt. Evans, F.R.S., the present Superintendent of the Compass Department of the Navy, in laying before the Society several valuable papers containing the results of the mathematical theory applied to observations made on board the iron-built and armour-plated ships of the Royal Navy. Owing in great measure to these researches, the system practised in the Navy has been brought to its present advanced state. The outline of the system may be stated briefly as follows : — 1 . As regards the building of ships. It has been ascertained that the amount of disturbance is greatest in iron ships which are built (in British ports) with their heads to the North, and is still further and greatly increased in armour-plated ships when they are plated with their heads in the same direction in which they were built. It is therefore desirable that iron ships should not be built with their heads to the north, and that armour-plated ships should be plated in the reverse position to that in which they were built. 2. In respect to the fitting of ships. It is held to be essential that in every ship a Standard Compass should be fixed in a position selected, not for the convenience of the helmsman or of the builder, but for the moderate and uniform amount gf the deviation at and around it, and where every facility exists for the examination of errors, by comparison 1865.] President's Address. 501 with the azimuths of celestial objects, or by terrestrial bearings. No iron of any kind should be placed, or should be suffered to remain, within a certain distance of the Standard Compass ; in the British naval service this distance is 7 feet : and all vertical iron, such as stanchions, arm-stands, &c., should be at a still greater distance ; in the British naval service this distance is 14 feet, — whether on the same deck or immediately below it. .It is not difficult to select a place where the Standard Compass can be most advantageously placed ; but it is difficult, and some more stringent measures are required than at present exist, to induce ship-builders to adapt the arrangements of the vessel to the requirements of the compass. 3. In respect to those who have to navigate the ship. Every iron ship should be swung when her cargo is complete, and when she is ready in all respects for sea. Tables of the deviation of the Standard Compass on each course should be made according to the directions now universally adopted in Her Majesty's Navy, the tabular deviations being applied as correc- tions to the courses steered. The table of deviations to be carefully watched as the ship proceeds on her voyage, by comparison with the azi- muths of celestial objects, and reformed as changes in the geographical position of the ship, or in the magnetic condition of her iron, take place, according to rules which have been devised for that purpose, confirmed by experience, and published by authority. By a strict adherence to the precautions, arrangements, and practices which have been thus briefly sketched, the compass may still, in great measure, retain its place as the invaluable guide to the mariner in iron ships, as it was formerly in wooden ships. But with the increased employment of iron increased vigilance is re- quired in those on whom the responsibilities devolve. The assiduous labours of several eminent men, and prominently amongst them of Mr. Smith, have placed it in the power of any intelligent seaman to navigate his iron ship with safety ; but it cannot be too strongly inculcated, that no processes of supposed correction — whether tabular or mechanical — should be allowed to interfere with the habitual and constant practice of examin- ing the Standard Compass, on all occasions when the state of the heavens will permit, by comparisons with celestial objects. The benefits of Mr. Smith's labours have not been confined to our own Navy. The works to which he has contributed have been translated into the German, Russian, and French languages. The British system has been adopted in Hussia, whose vessels have to navigate a sea in which the mag- netic dip, and consequently the deviation of the compass, is even greater than in our own seas. A Compass Observatory has been established at Cronstadt to fulfil the same purposes as our Compass Observatory at Woolwich. Amongst our neighbours the French, whose fleets approximate the nearest to our own in the species of defensive armour which is perilous to their navigation, the system adopted in this country to preserve the utility of the compass has been the subject of a special mission appointed 502 Anniversary Meeting. [Nov. 30, by the Government, and of a Report addressed to the Minister of the Marine by M. Darondeau, entitled " Rapport a son Excellence le Ministre de la Marine sur une Mission accomplie en Angleterre pour ctudier Ics questions relatives a la regulation des Compas." The principal conclu- sions of this Report in reference to the compass by which the ship's course is to be directed, may be stated in a few words ; and I shall employ for this purpose M. Darondeau's own expressions, as they are a remarkable testimony to the value of the system adopted in the British Navy. " Etablir sur tous les batimens un ' Standard Compass,' ou compas de relevement a poste fixe, qui ne serait pas corrige. Ce compas devrait ctre assez eleve pour permettre de prendre les relevemens par dessus le bastin- gage ; il devrait en outre etre place dans la position la plus favorable pour n'etre soumis qu' a la force totale du navire, et non aux forces perturba- trices provenant de pieces de fer isolees. Dans ce but on I'eieverait de maniere a le soustraire a ces dernieres forces perturbatrices. " Ce compas ne serait jamais corrige" The italics are mine ; but the repetition of this last injunction is M. Da- rondeau's own, and is emphasized by him by being made to occupy a line by itself. M. Darondeau also recommends the employment in the French Marine of compasses similar to the Admiralty compass of the British Navy, having four needles attached to the card in the manner and for the purposes originally suggested by Mr. Smith ; and he does not fail to urge on his countrymen the indispensable duty of examining the deviations of the Standard Compass by reference to the heavenly bodies, whenever the state of the weather will permit. MR. SMITH, Receive this Medal which the Council has awarded you in testimony of their high sense of the value of your researches on the magnetism of ships. I trust that you will always regard it with a real pleasure, agreeing well with the yet higher pleasure derived from the consciousness of the essen- tial service your generous labours have rendered to the mariners of this and all other maritime nations. I will venture on the personal expression of the high gratification which my position in this chair allows me this day to enjoy — in mine being the hand which places this Medal in that of one who from his earliest youth has been the object of my ever-increasing high esteem and warm friend- ship. 18C5.] President's Address. 503 NOTES. NOTE A. The steps which have led to the procurement of a large reflecting telescope for active employment in the southern hemisphere originated in a resolution passed by the General Committee of the British Association assembled at Birmingham in September 1849, during the Presidency of the Rev. Dr. Thomas Romney Robinson. The resolution was as follows : — " That an application be made to Her Majesty's Government to esta- blish a reflector of not less than 3 feet in diameter at the Cape of Good Hope, and to make such additions to the staff of that observatory as may be necessary for its effectual working ; and that the President be requested to communicate with the Earl of Rosse and Sir J. Herschel, the Astronomer Royal, Sir Thomas Brisbane, and Dr. Lloyd on the subject ; and to ob- tain the concurrence in the application of the Royal and Astronomical Societies of London, the Royal Society of Edinburgh, and the Royal Irish Academy." The communications thus directed having been made, the President and Officers of the British Association received on the 9th of the No- vember following (1849) a reply from the Council of the Royal Astrono- mical Society, declining to cooperate with the British Association in re- commending the establishment of a large reflector at the Cape of Good Hope, on the ground that " a system of observations essentially meridional, as those of the Cape Observatory now are, has very little in common with a system of observations with a large reflector. The Council conceive that the subjects and methods and difficulties of the last-mentioned observa- tions absolutely require the entire energies of a superintendent fitted by his talents and education to be the head of an observatory. They con- sider therefore that the proposal in question amounts to nothing less than the establishment of a new observatory, a measure which the Council [of the Royal Astronomical Society] are not prepared to recommend." The reply of the Council of the Royal Society of Edinburgh was dated December 10, 1849, and was as follows: — "The Council [of the Royal Society of Edinburgh] are of opinion that it is not expedient at present to take part in the proposed application to Government relative to the large reflecting telescope, suggested to be sent to the Cape of Good Hope." No specific reply appears to have been received from the Royal Irish Academy, it having been stated in a letter from Dr. Lloyd to the Rev. Dr. Robinson, that " the Council of the Royal Irish Academy had de- clined to enter upon the subject, as not being strictly within the province of the Academy." 504 Anniversary Meeting. [Nov. 30, The reply from the Royal Society of London was dated April 19, 1850, and was as follows : — " The President and Council of the Royal Society agree entirely with the British Association in their estimate of the importance of the active use of a large reflector in the southern hemisphere, and deem the subject well worthy of a recommendation to Her Majesty's Government, in which they would be ready to concur ; but they would deem it advisable that, in such recommendation, the locality to which the telescope should be sent, and the establishment to which its use should be confided, should be left to the choice of Her Majesty's Government." These replies were submitted to the Council of the British Association on the 20th of May, 1850, when the Council passed the following reso- lution : — " That the object which the General Committee had in view in their resolution for a recommendation to establish a large reflector at the Cape of Good Hope, viz. the systematic observation of the nebulae of the Southern Hemisphere with an instrument of great optical power, would be accomplished by the establishment of such an instrument in any other part of the Southern Hemisphere which should be equally suitable for the observations in question ; the Council are therefore of opinion that the President will be carrying out the spirit of the recommendation of the General Committee, by putting the proposition to be made to Her Ma- jesty's Government in the general form suggested by the President and Council of the Royal Society, and by concurring with the President of the Royal Society in submitting the recommendation so modified to the consideration of Her Majesty's Government." The President (Dr. Robinson) was further requested to draw up a Me- morial to accompany the Resolution, and to communicate thereupon with the Earl of Rosse, President of the Royal Society. The Memorial pre- pared by Dr. Robinson, and concurred in by the Earl of Rosse, was presented, in accompaniment with the Recommendation of the General Committee thus amended, to Earl Russell (then Lord John Russell), the First Lord of the Treasury. The Memorial itself may be referred to in the " Report of the Council to the General Committee of the British Association assem- bled at Edinburgh in July 1850." The reply from the Treasury was as follows : — « " Treasury Chambers, August 14, 1850. « SIR, — I am commanded by the Lords Commissioners of Her Majesty's Treasury to acquaint you that your Memorial of the 3rd ultimo, addressed to Lord John Russell, applying, on behalf of the British Association for tbe Advancement of Science, for the establishment in some fitting part of Her Majesty's dominions of a powerful Reflecting Telescope, and for the ap- pointment of an observer charged with the duty of employing it in a review of the Nebulae of the Southern Hemisphere, has been referred by His Lordship to this Board ; and I am directed to inform you with re- 1865.] President's Address. 505 ference thereto, that while My Lords entertain the same views as those expressed by you as to the interest attaching to such observations, yet it appears to their Lordships that there is so much difficulty attending the arrangements which alone could render any scheme of the kind really beneficial to the purposes of science, that they are not prepared to take any steps without much further consideration. '* I am, Sir, &c. &c., " G. CORNEWALL LEWIS." This reply, though failing to meet the not unreasonabte expectations which had been founded on the intrinsic importance of the subject itself and on the earnest recommendation it had received from the two principal scientific institutions of the kingdom, was still so far satisfactory that it conveyed the approval of the Government of the principle of the proposi- tion ; it was reasonable to believe therefore that by perseverance and by a judicious selection of times and opportunities the object would be eventually secured. Such was the view taken by its promoters ; and in accordance with this view the subject was again brought under the consideration of the British Association at their Meeting at Belfast in September 1852, in the opening address of the President, suggesting that a decision should be taken — whether any, and if any, what official step should be adopted for its immediate furtherance. After the usual discussions in Sections and Committees, the General Committee passed the following Resolution : — " That it is expedient to proceed without delay in the establishment in the Southern Hemisphere of a Telescope not inferior in power to a 3-feet Reflector ; and that the President (Col. Sabine), with the assistance of the following gentlemen, viz. the Earl of Rosse, Dr. Robinson, Lord Wrot- tesley, Professor Adams, the Astronomer Royal, J. Nasmyth, Esq., Wm. Lassell, Esq., Sir'D. Brewster, and E. J . Cooper, Esq., be requested to take such steps as they shall deem most desirable to carry this resolution into effect." The first step taken by this Committee was to communicate the resolu- tion to the President (The Earl of Rosse) and Council of the Royal Society, who (on the 25th of November, 1852) resolved as follows : — " That the President and Council agree with the British Association in considering it desirable to proceed without delay in obtaining the establish- ment of a Telescope of very great optical power for the observation of Nebulce in a convenient locality in the Southern Hemisphere j and that a Committee be appointed to take such steps as they may deem most desi- rable to carry out this resolution. The Committee to consist of ihe Presi- dent, Officers, and Council of the Royal Society, with the addition of Sir John Herschel, Sir John Lubbock, and the Dean of Ely." It was also agreed that the Committee should act conjointly with the gentlemen named in the Resolution passed by the British Association. The joint Committee applied themselves in the first instance to a con- 506 Anniversary Meeting. [Nov. 30, sideratiou of the most suitable construction and dimensions of a telescope for the desired purpose. This was effected by a correspondence amongst the members of the Committee, passing through the Secretary of the Royal Society, the letters being printed for greater convenience in circulation. The proceedings of this Committee were terminated by a meeting of its mem- bers at the apartments of the Royal Society on July 5, 1853, the Earl of Rosse, President, in the Chair; when the following resolutions were passed : — " I. That the Committee approve the proposition made by Mr. Grubb, and contained in Dr. Robinson's letter of June 30, 1853, for the construc- tion of a/oM?--foot Reflector. " 2. That application be made to Her Majesty's Government for the necessary funds. " 3. That the Presidents of the Royal Society and of the British Asso- ciation, accompanied by Dr. Robinson, who was associated with the Earl of Rosse in the former application, and Mr. Hopkins, the President elect of the British Association, be a deputation to communicate with Government respecting the preceding Resolutions. " 4. That the Earl of Rosse, Dr. Robinson, Mr. Warren De la Rue, and Mr. Lassell be a Subcommittee for the purpose of superintending the pro- gress of Mr. Grubb' s undertaking." No record appears to have been made of the subsequent steps taken by this Committee ; but it is understood that the application was made to the Earl of Aberdeen, who had become First Lord of the Treasury, and that the reply received was that " no funds could be then spared as the country was engaged in the Crimean war ; but that when the crisis then impending was past the matter should be taken up." Lord Aberdeen's retirement from office, and subsequent death, rendered this promise of no avail. I must now advert to a circumstance which has exercised a most beneficial influence on the proposition for a southern telescope, and has contributed greatly to bring it to its present advanced stage. Amongst the Members of the Mathematical and Physical Section of the British Association who took part in the discussions relating to the telescope at the Belfast Meet- ing, there was one, Mr. William Parkinson Wilson, Professor of Mathe- matics in Queen's College, Belfast, who was remarked for the deep and earnest interest with which he viewed the subject. Appointed shortly afterwards to the Mathematical Chair in the University of Melbourne, Professor Wilson appears to have been impressed by the suitability of Melbourne for such a telescope, both from its latitude and climate, and from the increasing wealth and public spirit of its inhabitants manifested in the liberal support given to many scientific institutions. Melbourne enjoyed also at that time the great advantage of a Governor, Sir Henry Barkly, whose education and acquirements enabled him to appreciate the importance in such a colony of scientific cultivation. Being appointed Hon. Secretary of the Board of Visitors of the Melbourne Observatory, 1865.] President's Address. 507 then in process of organization, and with the sanction of the Governor, who was President of the Board, Professor Wilson submitted to the considera- tion of the Observatory Committee of the Philosophical Institute of Vic- toria a scheme for the establishment at Melbourne of a reflecting telescope of 4 feet aperture to carry out the objects which had been proposed by the Royal Society and British Association, as already narrated. In this pro- position Professor Wilson was warmly supported by Captain Kay, R.N., F.R.S., one of the Board of Visitors, who had been for several years Super- intendent of the Magnetical and Meteorological Observatory in the sister colony of Tasmania. After discussions at several Meetings, a Memorial was adopted and presented to the Chief Secretary of the Government, adverting to the favourable condition of the finances of the colony, and urging the establishment of such a telescope at Melbourne " as suited alike to render an important service to science, and to redound highly to the credit of the colony, both in Australia and in Europe." The favourable reception of this Memorial by the Government of Vic- toria, and the proceedings which followed, will be best explained by the following despatch from Sir Henry Barkly to the Duke of Newcastle, then Secretary of State for the Colonies, transmitted to the Royal Society on October 10, 1862, accompanied by the expression of His Grace's assurance that " the Royal Society would do whatever may be in their power for encouraging science in the colony of Victoria." Governor Sir H. Barkly to the Duke of Newcastle. (Copy.) Government Offices, Melbourne, M* LORD DUKE, 23rd July, 1862. The Board of Visitors to the Melbourne Observatory, over which I have the honour to preside, being of opinion that the project long entertained of erecting in the Southern Hemisphere a telescope of much greater optical power than that used by Sir John Herschel at the Cape of Good Hope, would be materially advanced by an expression of interest and sympathy on the part of scientific men in England, has requested me to bring the subject under Your Grace's notice, with a view to its being submitted for the Report of the Royal Society of London and the British Association for the Advancement of Science. I have great pleasure in forwarding accordingly, with the approval of my advisers, an extract from the Board's Minutes, together with the accom- panying letter from its Honorary Secretary, Professor Wilson, in which the reasons for this step are so fully set forth, and the advantages likely to arise from obtaining a powerful instrument for this purpose so clearly explained, as to leave nothing for me to add beyond earnestly soliciting Your Grace's good offices in the matter. It will be observed that the pecuniary cooperation of the British VOL, xiv. 2 Q 508 Anniversary Meeting. [Nov. 30, Government is not applied for ; but I need hardly say that even the smallest donation from that quarter would much facilitate raising the neces- sary funds. I avail myself of this opportunity to put Your Grace in possession of the Second Annual Report of the Board of Visitors, from which it will be found that a commencement has been made in the erection of the new Observatory, advocated in the Report previously transmitted ; and I am glad to be able further to state that a sum of .£4500 has since been voted by the Legislature for the completion of the requisite buildings. Should it be possible, therefore, to add an equatorially mounted tele- scope, the Astronomical Branch of the Observatory will be rendered com- plete, and no greater expense than at present will be incurred for the Staff attached to it. I have, £c., (Signed) HENRY BARKLY. His Grace the Duke of Newcastle, K.G., fyc. fyc. fyc. Professor Wilson to Sir H. BarJcly. (Copy.) The University, Melbourne, 16th July, 1862. SIR, I have the honour, by direction of the Board of Visitors to the Obser- vatories, to forward to Your Excellency the accompanying extract from the Minutes of a Meeting held yesterday, and to express a hope that you will comply with the request contained in it. Though entertaining no doubt of the importance of the results to be obtained by such a telescope as is recommended, or of the conspicuous and creditable position which Melbourne would consequently occupy in the eyes of all persons in Europe who take an interest in Science, the Board is desirous of obtaining an expression of opinion from scientific men in England, because it is due to those who may be asked to contribute towards its accomplishment that the importance of the object should be attested by higher scientific authority than the Board can lay claim to ; because also it considers that every means should be used to obtain, so far as funds will permit, the best instrument which modern skill and recent inventions render possible ; because, finally, the Board feel that, whether the cost of the instrument be defrayed wholly or partially by private contributions or a grant from the Legislature, public sympathy will be much more strongly enlisted in its favour by a statement of the interest taken in the matter in Europe, and by the approval of the Imperial Government, than by any representation which the Board can make. I have, &c., (Signed) W. P. WILSON, Secretary to the Board of Visitors. His Excellency the Governor. 1865.] President's Address. 509 Extract from the Minutes of a Meeting of the Board of Visitors to the Observatories, held 15 July 1862. " The attention of the Board having been drawn to the following cir- cumstances— "I. That, as long since as 1849 the facts brought to light by Lord Rosse's Telescope were judged by the Royal Society of London and the British Association for the Advancement of Science to be so important as to justify them in making an urgent appeal to the British Government for the erection, at some suitable place in south latitude, of a telescope for the examination of the multiple stars and the nebulae of the Southern Hemi- sphere, having greater optical power than that used by Sir John Herschel at the Cape of Good Hope ; which appeal there is little doubt would have been successful but for the Russian war and the consequent expenditure ; " II. That, since that time, Lord Rosse reports that he has discovered systematic changes in some of the most important northern nebulae ; " III. That the interest and scientific importance of the solution of the problem of their physical structure, as well as the probability of its accom- plishment, are thus greatly increased ; " IV. That some of the most important nebulae, and those presenting the greatest variety of physical features in close proximity, can be observed only in places having a considerable southern latitude ; " V. That the geographical position and clear atmosphere of Melbourne render it peculiarly suitable for this work, and that the arrangements already made for the establishment of an Astronomical Observatory on a permanent footing offer great facilities for carrying it on ; " VI. That, independently of the especial object to which such telescope would be applied, an Astronomical Observatory cannot be considered com- plete without an equatorially mounted telescope of large optical power : " It was Resolved, — " 1st. That, in the opinion of the Board, the establishment of such a tele- scope in Melbourne would materially promote the advancement of science. "2nd. That, before applying to the Colonial Government for any pecu- niary grant in aid of this object, His Excellency the Governor be requested to obtain, through the Secretary of State for the Colonies, an expression of opinion from scientific men in England as to the importance of the results to be expected from it, the most suitable construction of telescope for the purpose, both as to the optical part and the mounting, its probable cost, and the time requisite for its completion." On the receipt of this communication from the Colonial Office, a corre- spondence ensued, passing through myself as President of the Royal Society, consisting of twenty-three letters, the writers being Mr. Lassell, Sir John Herschel, the Earl of Rosse, Dr. Robinson, Mr. Grubb, and Mr. De la Rue, which was printed for private circulation amongst the Fellows of the Royal Society. The correspondence led to and terminated in the following Report 2a2 510 Anniversary Meeting . [Nov. 30, from the President and Council addressed to the Duke of Newcastle, in reply to His Grace's communication of October 10, 1862 : — " Report of the President and Council of the Royal Society respecting the proposal of erecting in Melbourne a Telescope of greater optical power than any previously used in. the Southern Hemisphere. "1. The President and Council learn with pleasure that the Board of Visitors at the Melbourne Observatory have proposed resolutions, indica- ting their sense of the importance of erecting at Melbourne an equatorially mounted Telescope of great optical power, and that the proposal is favour- ably regarded by Sir Henry Barkly, Governor of Victoria, and by His Grace the Secretary for the Colonies. In respect to the importance which the President and Council attach to such an undertaking, they need do no more than refer to the fact that in the year 1850 the Royal Society and the British Association for the Advancement of Science presented a joint Memorial to Her Majesty's Government, in which they urged the establish- ment of such a telescope at some suitable place in the Southern Hemi- sphere. The scientific objects to be attained thereby are so clearly stated in that Memorial, of which a copy is enclosed, and in the Resolutions of the Board of Visitors of the Melbourne Observatory, in July 1862, that the President and Council feel it unnecessary to do more than refer to these documents. "2. Since the presentation of the Memorial of 1850, an equatorially mounted telescope of greater optical power than that then recommended has actually been constructed by Mr. Lassell, at his own expense, in Eng- land, and erected in Malta, where he is now occupied in making obser- vations with it : we have now, therefore, in addition to our previous know- ledge, the benefit of his experience. In referring to Mr. Lassell's Telescope, the President and Council wish it, however, to be understood that they do not conceive that it should necessarily be copied in all respects, and that for the present they think it best to leave the details of construction in many respects open to further consideration. "3. When the subject was previously under consideration, letters were written to some of the most eminent practical astronomers of Great Britain and Ireland, requesting them to state their opinions as to the best mode of construction ; and a correspondence ensued, of which a printed copy is sent herewith. After receiving the communication from the Colonial Office of the 10th of last October, the President wrote to the four gentlemen who were appointed as a Committee on the former occasion to superintend the construction of the instrument (in case the Government should accede to the request), and also to Sir John Herschel, enclosing a copy of the former correspondence, and asking whether their views had in any way changed in the interval. The answers received from each have been circulated among the others, as was done on the former occasion, and have in most cases elicited additional remarks. "4. Availing themselves of the information thus so kindly afforded 1865.] President's Address. 511 them, the President and Council have to recommend as follows regarding the construction of the instrument contemplated. " («) That the telescope he a reflector, with an aperture of not less than four feet. This is essential, as no refractor would have the power required. " (b) That the large mirror be of speculum-metal. Such mirrors can be constructed with certainty of success, and at a cost which can be foretold ; whereas the recently introduced plan of glass silvered by a chemical process has not yet been sufficiently tried on so large a scale as that contemplated. " (c) That the tube be constructed of open work, and of metal. Lord Rosse has recently changed the tube of his three-foot altazimuth from a close to an open or skeleton one, and it is understood that he intends doing the same with his great telescope. Mr. Lassell's tube is also an open one, which his experience leads him decidedly to prefer. *' (d) The telescope should be furnished with a clock-movement in right ascension. " (e) Apparatus for repolishing the speculum should be provided. " (/) With respect to the form of reflector to be adopted, some differ- ence of opinion exists, as the Newtonian and Cassegrainian have each some advantages not possessed by the other. On this point further corre- spondence appears desirable ; but as the main features of the scheme are the same in both cases, there does not appear to be any occasion to wait till this point shall have been finally decided. " 5. With respect to the cost, something must depend on the solidity of the construction and the perfection of the workmanship ; but if it be assumed that the workmanship shall be of the best description, and the instrument furnished, as seems desirable, with polishing apparatus, and a second speculum for using while the other is being polished, it is probable that the cost will not fall much short of ^OOO. " 6. It is estimated that the construction of the instrument will occupy about eighteen months. " 7. It seems highly desirable that the future Observer should come to England during a part at least of the time occupied in the construction of the instrument, in order that he may become thoroughly acquainted with all its details, and especially with the mode of repolishing ; and also that he may personally acquaint himself with the working arrangements followed at the Observatories of the Earl of Rosse and Mr. Lassell, who have expressed thjeir willingness to afford him every facility." This Report, accompanied by several copies of the Correspondence ad- verted to, was transmitted in due course to Melbourne. In 1863 Mr. Lassell made the most liberal offer of freely presenting for the observations at Melbourne his own 4-foot reflector, with which he had been carrying on a series of observations at Malta, as soon as that series should be completed, or in the coarse of a year or two. The construction of this telescope had been largely considered and discussed in the corre- spondence already adverted to. On Mr. Lassell's munificent offer being 512 Anniversary Meeting. [Nov. 30, transmitted to Melbourne, the authorities there were at first disposed to embrace it ; but subsequently, on further consideration and correspondence, they determined to revert to the original plan, of a telescope to be con- structed by Mr. Grubb expressly to meet in the most perfect attainable manner all the special requirements of the case. This plan is described in a letter addressed to Dr. Robinson on the 3rd of December, 1862, being the thirteenth letter in the printed Correspondence referred to. It seems scarcely possible to doubt the wisdom, in every point of view, of the decision thus arrived at. The alterations which would have been required in Mr. Lassell's telescope would have demanded a large proportion of the time and the ex- pense needed for the construction of the new one ; and the result would have been that Europe would have lost all the services which Mr. Lassell's tele- scope may still perform — while Australia would have had a much less per- fect instrument, for the especial purposes in view, than it will now possess. In April 1864 a proposition for a grant of ^65000, to cover the expense of constructing a telescope, was submitted to the Colonial Legislature by one of its members, Mr. Alexander John Smith, also a Member of the Board of Visitors of the Observatory, who, previously to his residence in Victoria, had been one of that band of highly-trained naval observers who, under the command of Sir J. C. Ross, had accomplished, between the years 1839 and 1843, the Magnetic Survey of the Antarctic regions, and had subsequently become one of the officers employed with Capt. Kay in the Magnetical and Meteorological Observatory at Hobarton. This pro- position was successful ; and the notification received from Professor Wilson is printed in the text of this Address, p. 483. NOTE B. The number of hourly tabulations from the photographic traces of the bifilar magnetometer at Kew, between January 1, 1858, and December 31, 1864, is 60,491 : of these, the number in which the amount of dis- turbance from the normal of the same year, month, and hour equalled or exceeded 0*150 division of the scale, or -0015 of the total horizontal force at Kew, was 5932, being about one in ten of the whole number of tabulated hourly values. The aggregate value of the 5932 disturbed ob- servations in parts of the bifilar scale, of which 1 inch equals "01 of the whole horizontal force, was as follows : — Year ending December 31, 1858 267*893 inches. 1859 369-286 „ 1860 270-349 „ 1861 206-748 „ 1862 183-645 „ 1863 114-642 „ 1864 114-725 „ The mean annual value in the seven years is 218*184 inches ; and the ratios of disturbance, in each of the seven years, to the mean annual value are as follows : — 1865.] President's Address. 513 Year ending December 31, 1858 1'23 1859 1-69 1860 1-24 1861 0-95 1862 0-84 1863 0-53 1864 0-53 NOTE C. Mean Annual Values of the Magnetic Inclination at Toronto deduced from the Monthly Determinations ; reprinted from Table LIII. (p. 93) of the 'Abstracts of Observations made at the Magnetic Observatory at Toronto,' published by its Director, G. T. Kingston, Esq. The years 1863 and 1864 are added from the Numbers of the ' Canadian Journal of Science.' " The monthly determinations were commonly made on three consecu- tive days, as nearly as possible about the middle of the month. One determination was usually made each day between noon and 1 P.M. The monthly and annual means were derived directly from the observations." Years. 1853. 1854. 1855. 1856. 1857. 1858. 1859. 1860. 1861. 1862. 1863. 1864. Yearly ] Means. \ 75°+ J 22-17 22-96 23-54 23!19 21-47 20-93 24-06 24-32 24-44 24-98 24-55 23-75 On the motion of Mr. "Warren De la Rue, seconded by Colonel Yorke, it was resolved, — " That the thanks of the Society be returned to the Pre- sident for his Address, and that he be requested to allow it to be printed." The Statutes relating to the election of Council and Officers having been read, and Mr. De la Rue and Mr. Merrifield having been, with the consent of the Society, nominated Scrutators, the votes of the Fellows present were collected, and the following were declared duly elected as Council and Officers for the ensuing year : — President. — Lieut.-General Edward Sabine, R.A., D.C.L., LL.D. Treasurer.— William Allen Miller, M.D., LL.D. f William Sharpey, M.D., LL.D. I George Gabriel Stokes, Esq., M.A., D.C.L. Foreign Secretary.— Professor William Hallows Miller, M.A. Other Members of the Council. — John Frederic Bateman, Esq. ; Lionel Smith Beale, Esq., M.B. ; William Bowman, Esq. ; Commander F. J. Owen Evans, R.N. ; Edward Frankland, Esq., Ph.D. ; Francis Gallon, Esq ; John Peter Gassiot, Esq.; John Edward Gray, Esq., Ph.D.; Thomas Archer Hirst, Esq., Ph.D. ; Sir Henry Holland, Bart., M.D., D.C.L. ; William Odling, Esq., M.B. ; Sir John Rennie, Knt. ; Prof. Warington W. Smyth ; William Spottiswoode, Esq., M.A. ; Paul E. Count de Strzlecki, C.B., D.C.L. ; Vice-Chancellor Sir W. P. Wood, D.C.L. The thanks of the Society were voted to the Scrutators. 514 Financial Statement. [Nov. 30, £ Ml i ^ •g i | 111 ':& N 4^ j^ -2 t t J in r£ . . 0 1 1 §c2 • g ^ ^r^-2 : T3 SJD.S o r^§.5 &g • s-s p^_- 5*, " h Jl a _M»a ^g « Ml §11 1 1 i ^335 ^> I 2 ^°S||o f i I { fe I ^ ^ -- .S «%«»»» 5 1865.] Financial Statement. 515 516 Correspondence on Magnetism of Ships, [Nov. 30, The following Table shows the progress and present state of the Society with respect to the number of Fellows : — Patron and Royal. Foreign. Having com- pounded. Paying £ 2 12s. annually. Paying £4 annually. Total. November 30, 1864 . Since elected 6 + 1 49 320 -j-9 3 276 + 10 654 + 20 Since deceased .... — 1 — 2 —20 — 10 —33 Since withdrawn _1 _1 Since defaulter — 1 _1 November 30, 1865. 6 47 309 3 274 639 Further Correspondence between the Board of Trade and the Royal Society, in reference to the Magnetism of Ships, and the Meteo- rological Department *. Mr. Farrer to General Sabine. " Board of Trade, Whitehall, 25th July, 1865. " SIB, — I am directed by the Lords of the Committee of Privy Council for Trade to acknowledge the receipt of your letter of the 25th May, and its inclosed Memorandum, calling attention to the subject of the adjust- ment of compasses in iron vessels. "The Memorandum states that the subject of the deviation of com- passes is one which has hitherto been regarded as too intricate and obscure to be made the subject of practical rules for seafaring men, but that recent experience has placed the science on a sound basis, and has made it pos- sible to frame rules which there will be no practical difficulty in applying. " The Memorandum further intimates what those rules should be with respect to the placing and adjustment of compasses, and suggests that mea- sures should be taken by the Board of Trade to enforce their observance. It also suggests that steps should be taken to compel Merchant Officers to become acquainted with them ; and finally recommends that for the ac- complishment of these purposes an Officer should be appointed, whose duty it should be, in communication with the Compass Department of the Ad- miralty, to aid the Board of Trade in carrying it into effect. * Published by order of the Council. 1865.] and on the Meteorological Department. 517 " The Board of Trade desire me in reply to return their thanks to the Royal Society for calling attention to a subject which is of first-rate im- portance to the Mercantile Marine. They have no doubt that the present practice is far from satisfactory ; nor do they think that the steps taken by the Board of Trade under the provisions of existing Acts are such as to remedy the evil. At the same time they can see considerable diffi- culty in adopting all the suggestions made by the Royal Society. " The steps which the Board of Trade now take are as follows : — " The Merchant Shipping Act provides that the compasses of passenger steamers shall be adjusted to the satisfaction of the Board of Trade Sur- veyors, and according to regulations laid down by the Board of Trade. This duty the Surveyors do as well as the means at their disposal enable them to do, and according to regulations which will be found in para- graphs 83 to 86 of the accompanying ' Instructions to Surveyors.' " As regards the information of Masters and Mates, the Board of Trade have circulated a pamphlet, prepared by Mr. Towson, of Liverpool, which is, no doubt, known to the Royal Society, and have added a general ques- tion on the subject to the Examination-papers. " Under these circumstances it is to be considered whether the Board of Trade can, and whether, if they can, they ought to do more than they d either as regards the proper supply and adjustment of compasses, or as regards the diffusion of information on the subject. " As regards the first of these points, viz. the proper supply and adjust- ment of compasses, the Royal Society will, no doubt, concur with the Board of Trade in thinking that it is very undesirable for the Legislature or the Government, except under very exceptional circumstances, to take upon themselves responsibilities which properly belong to shipowners and insurers, or to dictate to those persons the mode in which they, shall carry on their business. The proper supply and adjustment of compasses is a matter so material to the safety and success of their undertakings, that motives of self-interest are likely to effect much greater and much better results than could be hoped for by the compulsory interference of a Go- vernment Department. These considerations will have to be very care- fully weighed before any attempt is made to obtain from the Legislature further powers for the regulation of compasses in merchant ships. And under the law, as it now stands, the Board of Trade do not see what effec- tual step they can take in the direction pointed out by the Royal Society. " In the first place, the powers under which they act only apply to pas- senger steamers, whilst the want which the Royal Society wish to meet is felt just as much in the case of other iron vessels, which are becoming more numerous every day. " In the second place, the powers of the Board of Trade only extend to obtaining a Certificate ' that the compasses have been properly adjusted.' They do not enable the Board of Trade or its Officers to see that the com- passes are good, or to require — what the Royal Society appears to consider 518 Correspondence on Magnetism of Ships, [Nov. 30, the most important condition of all — that there should be a Standard Com- pass (in addition to the Steering Compass) so placed as to be free from local attraction. " This Board cannot, therefore, do what is wanted under the present Acts. " There is, however, a body, namely, Lloyd's Register Committee, whose proper business it is to see that ships classed by them are seaworthy, and My Lords will refer this part of the subject to them, stating what they hear upon the subject from the Royal Society. This Board will also gladly communicate to Lloyd's any practical rules which the Royal So- ciety can furnish as to the supply, placing, and adjustment of compasses, and as to the effect upon them of different modes of construction of the hull of the ship. "Secondly. As regards the diffusion of information on the subject of compasses, especially among Merchant Officers, the first desideratum ap- pears to be a clear and intelligible Manual or set of directions upon the subject, containing such practical rules as the present state of Science can furnish, and such a statement of the principles as may be necessary for the comprehension of those rules. My Lords will be glad to be informed by the Royal Society if they can put them in the way of obtaining such a Manual. Any expense connected with its preparation will be readily de- frayed by the Board of Trade. " The next step to be taken would be to introduce the subject into places of nautical education. On this the Board of Trade can do nothing except communicate with the Science and Art Department, which they will gladly do on hearing from the Royal Society that such a Manual as above men- tioned is in preparation. "The third step would be to introduce the subject more effectually into Examinations in Navigation, and to have printed questions prepared for the purpose. On this point also the Board of Trade would be glad to know whether the Royal Society can give them information or assistance. One difficulty which will arise will be the difficulty in finding Examiners who have given sufficient attention to the subject, and the first step must pro- bably be to instruct the Examiners themselves. For this purpose also the suggested Manxial will be of great importance. " The steps suggested above may be taken with the aid of the Royal Society, without any such appointment by the Board of Trade of an addi- tional officer as the Royal Society suggest. " This disposes of most of the important points referred to. There arc two which still require notice. The Royal Society propose that the sug- gested new Officer of the Board of Trade shall assist at inquiries into wrecks, where questions arise concerning the deviation of the compass. Though the Board of Trade are not prepared to appoint a special officer for this purpose, or to commit the inquiry to such an officer, they think that it would be very useful if, in the cases of future inquiries into 1865.] and on the Meteorological Department. 519 wrecks, where important questions concerning compasses are likely to be raised, a person thoroughly acquainted with the suhject could attend and give the Court the benefit of his opinion. On this subject the Board will communicate with the Admiralty. " Lastly, the Royal Society refer to the possible improvement of the science by means of farther observations. As regards this, all the Board cf Trade could do would be to obtain observations from Masters of mer- chant ships, in the manner originally proposed by the Eoyal Society, when the Meteorological Department of this office was established. The whole subject of that department is now under consideration, and this branch of the subject of the Royal Society's letter will be considered in connexion with the rest of that department. " I have the honour to be, " Sir, " Your obedient Servant, " T. H. FARRER." " Major- General Saline, &fc. <$fc, 6fc., President Royal Society." Mr. Fane to General Saline. "Board of Trade, Whitehall, 12th August, 1865. " SIR, — I am directed by the Lords of the Committee of Privy Council for Trade to forward to you the inclosed copy of a letter received from the Secretary to Lloyd's Register, in answer to a communication from this Board relative to the subject of Compasses in Iron Ships. " I am, Sir, " Your obedient Servant, « Major-General Saline, $c. $c. $c., " W. S. FANE." President Eoyal Society." (Liclosure.) " Lloyd's Register of British and Foreign Shipping, 2 White Lion Court, Cornhill, 4th August, 1865. <( gIE) — I am directed to acknowledge the receipt of your letter dated 25th ultimo, with its inclosures, relating to the variation &c. of Com- passes in Iron Ships, and to acquaint you that it occupied the attention of the Committee of this Society at their Meeting yesterday. " It appears that it is a subject encompassed with difficulties, and that but little is known at present as to any method which shall ensure satis- factory action of compasses in iron vessels. " The Committee apprehend therefore that it will not be in their power to take any active steps in the matter ; but they will avail themselves of such means as arc at their disposal to obtain information on the important 520 Correspondence on Magnetism of Ships, [Nov. 30, subject thus brought under their notice, and will apprize the Board of Trade Authorities of the result of their inquiries. " I am, &c., (Signed) « GEO. B. SEYFANG, " T. H. Fairer, Esq., " Secretary." Secretary, Board of Trade, London.7' General Sabine to Mr. Farrer. " Llandovery, S. Wales, Aug. 28th, 1865. " SIB,— I beg to acknowledge the receipt of your letter (3027W) of the 12th inst., enclosing copy of a letter received from the Secretary to Lloyd's Register. They shall be duly laid before the Council of the Royal Society, together with your previous letter, at the first Meeting after the " From inquiries which I have made I have reason to believe that when the proper time shall come a Manual, such as you have referred to, for the instruction and guidance of the builders, fitters, and navigators of the iron ships employed in conveying passengers and merchandize, might be supplied by persons whose sound and practical knowledge qualify them eminently for rendering such a public sen-ice ; but a work which should satisfy all the requirements referred to in your letter cannot be prepared until the system to be adopted in the Mercantile Marine shall have been, to some extent at least, determined, and then not without the concurrence of the person or persons who should be charged with bringing the system into practical operation. " The success which has attended the steps taken by the Board of Admi- ralty to remedy the evils resulting from the disturbance of the compass in Her Majesty's Ships at a time when the science was in a comparatively rudimentary state, is owing to the combination of a proper code of instruc- tions with arrangements for their enforcement under official and competent superintendence, and may be advantageously referred to as a precedent should the Board be disposed to adopt a similar proceeding. " I have the honour to be, Sir, " Your obedient Servant, " T. H. Farrer, Esq.'' " EDWAUD SABISTE." Mr. Farrer to General Sabine. " Board of Trade, Whitehall, 23rd October, 1865. " SIR, — I am directed by the Board of Trade to acknowledge the receipt of your letter of the 28th August relative to the preparation of a Manual for the guidance and instruction of persons employed in the construction and navigation of iron ships. " In reply, I am to thank you for your communication, and to observe that the object of this Board, in proposing a Manual of this kind, was, in 1865.] and on the Meteorological Department. 521 the first and chief place, to place in the hands of those interested in ship- ping, the means of making themselves acquainted with the results of recent observation, which the Royal Society say can now be made available in practice, and the Board of Trade supposed, and still hope, that this may be done without involving the necessity of Government interference with, and supervision over, the Mercantile Marine. " I have the honour to be, Sir, " Your obedient Servant, " Major-General Saline, $c. $c. $c., " T. H. FAKKEK." President Royal Society" Mr. Farrer to General Saline. " Office of Committee of Privy Council for Trade, Whitehall, 24th October, 1865. " SIE, — I am directed by the Lords of the Committee of Privy Council for Trade, to acknowledge the receipt of your letter of the 15th June last, on the subject of the Meteorological Department of the Board of Trade, and to thank yourself and the Council of the Royal Society for the valu- able information, advice, and suggestions which it contains. " The Council of the Royal Society discuss the system of Weather Tele- graphy, and recommend that it shall be continued ; they approve of the proposal to hand over to the Hydrographer to the Admiralty such part of the observations collected in the Meteorological Department of the Board of Trade as he can make use of in constructing Charts for the use of sea- faring men. And they discuss and recommend the adoption of a new system of making and recording Meteorological Observations on land. " As regards, however, one branch of the subject, viz. Meteorological Observations made at sea, which formed the original object of the Meteo- rological Department, and the chief subject of the letter from the Royal Society of the 22nd February, 1855, the Board of Trade are not satisfied that they fully understand the present views of the Royal Society. " Your letter says in answer to Question 1, contained in my letter of the 26th May last, asking ' Are the objects specified in the Royal Soci- ety's letter of the 22nd February, 1855, still as important for the inte- rests of Science and Navigation as they were then considered ?' that ' The President and Council are of opinion that the objects specified in the Royal Society's letter of 22nd February, 1855, are as important for the interests of Science as they were then considered.' " And it further says in answer to Question 2, asking ' To what extent have any of these objects been answered by what has already been done by the Meteorological Department ?' that ' Much has without doubt been accomplished in the collection of facts bearing on Marine Meteorology; but as no systematic publication of the results has yet been made, the President and Council are unable to reply more specifically.' It is pro- bably for the reasons contained in this answer, that whilst the other sub- 522 Correspondence on Magnetism of Ships, [Nov. 30, jects above mentioned are fully discussed in your letter, the subject of these Meteorological Observations at sea is scarcely referred to. " It is, however, essential that the Board of Trade should be rightly informed upon this point before they can determine what steps should be taken with regard to the Meteorological Department. What is the value of the Observations at sea already collected '? what steps should be taken to make them useful ? and whether any, and, if any, what further observa- tions of the same kind should be collected, are questions which must be answered before any final arrangement can be made with respect to the other points mentioned in your letter. "With the view of clearing up these points, the Board of Trade are disposed to suggest the appointment of a small Committee, consisting, say of three or four persons, to examine the whole of the data already collected by the Meteorological Department; to inquire whether any, and what steps should be taken for digesting and publishing them ; and also to report whether it is desirable that observa- tions of a similar kind shall still continue to be collected. Such a Com- mittee would also in all probability be able to make valuable recommenda- tions as to the mode in which the business of the Department (if continued) shall be conducted, and as to the form in which the daily weather reports (by whomsoever they may be made) should be published. " If the Eoyal Society concur in this suggestion, the Board of Trade would ask them to appoint, as a member of the Committee, some gentleman whose acquirements would enable him to give valuable advice on the scien- tific part of the subject, and they would also ask the Admiralty to appoint another member. The Board of Trade will feel much obliged if you will favour them with the opinion of the President and Council on this sugges- tion. " With reference to the subject of Meteorological Observations on land, the Board of Trade do not clearly understand whether the Royal Society think that they should be substituted for, or be in addition to the Meteoro- logical Observations at sea, which were originally suggested by the Royal Society. They are disposed to agree with the Royal Society in thinking that any observations of a scientific nature would be better conducted under the authority and supervision of a scientific body such as the Royal Society, or the British Association, than of a Government Department. But they do not see how they could advise the Government to sanction any plan which would involve the establishment of two separate Offices for Meteo- rological purposes, one under the Board of Trade at Whitehall, and the other at Kew. It seems to them obvious that any assistance to be given by Parliament for Meteorological purposes will be more advantageously employed if concentrated at one place, and in one set of hands, than it can be if distributed among different Establishments. " I have the honour to be, Sir, " Your most obedient Servant, " The President of the Eoyal Society." " T. H. FARRER." 1865.] and on the Meteorological Department. 523 Staff -Commander Evans, R.N., to General Sabine. "Ilydrographic Office, October 23rd, 1865. " MY DEAR SIR, — I have forwarded to Burlington House for your accept- ance, a copy of my letter of suggestions relative to iron ships and their compasses, drawn up for the Board of Trade. " I gathered from a recent conversation that you were desirous of having this document, with the possible view of showing it to the Council of the Royal Society. I hope it may be found useful, as supplementary to your and their labours." " I am, my dear Sir, " Yours very faithfully, " General Sabine, cj-c. $c. cjv." " FRED. JNO. EVANS." Copy of Letter, with Appendices, from Staff- Commander Evans, H.N., to the Hydrographer of the Admiralty. " Admiralty, Ilydrographic Department, September 1865. " SIR, — Having carefully examined the correspondence between the President and Council of the Royal Society and the Board of Trade on the Magnetism of Ships, together with the Memorandum appended to the. President's letter of the 18th May, and having also considered the requi- sitions made by the Board of Trade to the Admiralty, by letter of the 28th July, 1865, to be furnished through the Compass Department with any information or suggestions on the subject, I have to submit the following for your consideration. " The Memorandum of the Royal Society is so comprehensive in its general views of the subject, that little remains to be added to the argu- ments and reasons therein advanced ; but in those matters of detail which would require attention in the event of action being taken on the recom- mendations of that body, there are several suggestions which present them- selves, and which possibly may be useful to the Board of Trade. To these I address myself. " To clearly understand the existing difference of administration, in com- pass-equipment and efficiency, between the Royal and Mercantile Marine, it is necessary to point out the views the Board of Admiralty entertained, and the steps they deemed it necessary to take on the introduction of steam machinery, and of so much iron in the general construction of ships of the Royal Navy. " Passing over the investigations successively made under their auspices by Flinders in 1814, Barlow in 1821, and Johnson in 1830 the Admiralty in 1837, ' deeming it necessary to apply some remedy to an evil so pregnant with mischief,' referring to the then defective state of the compasses sup- plied to Her Majesty's ships, < have determined to have the subject fully in- vestigated by a Committee of Officers conversant with magnetic instru- ments.' Resulting from the labours of this Committee, which extended VOL. XIV. 2 R 524 Correspondence on Magnetism of Ships, [Nov. 30, over several years, was not only the improvement of the compass itself, but the establishment of a system of compass-adjustment which has since been uniformly followed in Her Majesty's Navy. ! " The principal features of this system are the following : — " 1. The having in each ship a standard compass distinct from the steer- ing-compass, fixed in a position selected, not for the convenience of the helmsman, but for the moderate and uniform amount of the deviation at and around it, by which compass alone the ship is navigated. " 2. The requiring each ship to be swung, and to be navigated by a Table of Errors. " The Admiralty further at this period (1842), to ensure the proper manufacture and adjustment of the standard compass, especially the selec- tion of its position in the ship, and the general supervision of the ' swinging' of the ships of the Fleet, created a small Compass Department, and erected an Observatory and offices for the general examination of all the compasses supplied to Her Majesty's ships. As a matter of opinion, I may here express my belief that indirectly this latter establishment has tended very much to the improvement of compasses generally. " The Admiralty at this time also issued a small book of Eules, known as the * Practical Kules ' for ascertaining and applying the deviations of the compass ; these Rules have undergone revision and addition from time to time. (The latest edition is appended.) " General rules were also now laid down for guarding, in the equipment of the ship, against the near proximity of iron to the compass : extracts embracing the leading features of these Eules will be found in Appen- dix 1. " In 1862, consequent on the increased use of iron in the construction and armature of ships of war, there was issued for the service of the Fleet, the ,' Admiralty Manual of the Deviations of the Compass,' a work which, incorporating also the ' Practical Rules,' placed within the reach of the educated seaman the theory and general principles of the magnet- ism of ships, as also so much of the elements of terrestrial magnetism as affected the navigator. " In the Mercantile Marine, regulations for the examination and adjust- ment of the compasses are confined to sea-going passenger steamers. I gather from the letter of the Board of Trade, in reply to the Royal Society, as indeed I am aware from general personal knowledge, that practically, except perhaps in the larger shipping companies, these regulations are inoperative, or nearly so. " For example, there are no prescribed rules as to the number, the posi- tion, or the efficiency of the compasses, and there is no guarantee for the competency of the adjuster, in whose hands the whole arrangements are generally placed. In many ports, and especially that of London, there is inefficient provision for swinging the ships. ** It appears unnecessary to remark, after what has just been briefly 1865.] and on the Meteorological Department. 525 stated, that the system adopted to ensure security of navigation in the Royal Navy has no counterpart in the Mercantile Marine. The assimilation in practice of the two services, so far as relates to the more essential points, would certainly be a desirable end to attain. " I have already briefly detailed the two leading features of the Admi- ralty system : — The first of these (the navigating the ship by a standard compass) is in itself so simple, and has proved in practice so secure, and the neglect of it in many cases in merchant ships has been followed by such disastrous consequences, that I conceive there is no question that it should be enforced wherever there are the means of enforcement. Indeed, were it rendered imperative by law, that every vessel making a long sea voyage, and every iron vessel, whether employed coasting or foreign, should be fitted with a standard compass, I am of opinion this measure would not only directly tend to their secure navigation, but would indirectly tend to foster that knowledge of compass-laws and action now found to have be- come a necessity, when iron ships are the rule, and not the exception, as was the case some twenty years past. On the assumption that a measure of this nature must eventually obtain, I have appended a few short and simple rules (Appendix II.), which perhaps might be advantageously recommended by the authority of the Board of Trade, or Lloyd's Register Committee. . " With reference to the second leading feature of the Admiralty system : — . " For many years in the Royal Navy the adjustment practised consisted in the careful selection of a place for the standard compass, and the formation of a Table of Errors by the process of swinging the ship ; and this proved sufficient so long as the deviations were moderate in amount. " In many recent iron-built and iron-plated ships the amount of devia- tion is, however, so large that the employment of magnets to reduce the amount of deviation has become unavoidable ; but the correction by mag- nets, however perfect it may be, is not considered in the Royal Navy aa superseding the obtaining a Table of Errors and navigating the ship by that Table. " The benefits which have been derived in the Royal Navy, both as. regards the safety of ships, and the theoretical and practical knowledge of the subject we have thereby obtained, cannot, I think, be over-estimated ; and I may add that I consider that no compass can be said to be ' pro- perly adjusted' of which, whether compensated by magnets or not, a Table of Errors has not been obtained by the process of swinging the ship, and that Table examined by a competent person. ~ " Closely connected with the subject is that of the construction of the compass itself, as regards form and workmanship, magnetic power, and adjustment. This subject received much of the attention of the Committee I have referred to ; and the result of their labours was the production of the 'Admiralty Standard Compass,' an instrument which has stood the test of twenty-five years' use, with little modification introduced, and 2 R2 526 Correspondence on Magnetism of Ships, [Nov. 30, which has been adopted in all countries which directed their attention to this subject. " Although indirectly the introduction of this compass into the Royal Navy has been the cause of much improvement in the compasses of the Mercantile Marine, there is still room for improvement. At present much expense is incurred in matters which are merely ornamental, and in some cases prejudicial. Probably much advantage would be derived from a model compass being fixed upon, which at a moderate price would supply the Mercantile Marine with the great desideratum of a compass of suffi- cient delicacy and accuracy. Considering that a few notes relating to the efficient points of a compass may prove useful, these notes will be found as Appendix III. "There are yet two features in the ' Compass question' which appear to me as being worthy of consideration in any system that may be con- templated for assimilating the practice of the Mercantile Marine to that of the Royal Navy. These are, — " 1st. As to the efficiency of those who engage to perform the adjust- ments. " 2nd. The periods for examining the adjustments. " By constant practice, but without any very clear knowledge of the principles of magnetism, several [skilful adjusters of compasses are to be found at some of the great mercantile ports. These ' adjusters ' must, from their practice, be now well known to the Board of Trade Surveyors. The registration of their names, and of the firms employing them, either by the local Marine Boards or by Lloyd's Committee, might be a desirable step to take as a preliminary measure. " The arrangements for swinging ships, I have also heard, are either defective, or practically do not exist, at most of the mercantile ports ; might not the Board of Trade Surveyors report upon the nature of existing arrangements, and the means generally adopted by the ' adjusters ?' " As to the periods for examining the adjustments, the recommenda- tions of the Liverpool Compass Committee (see page 40, 3rd Report, 1861) appear to me to fully meet the case, and have such an important bearing on the secure navigation of iron ships, that I gladly bring them again to notice. " ' There appears sufficient reason for requiring that a new iron sailing ship or steamer should be swung immediately before each of the first two or three voyages ; that all iron vessels should be swung immediately before the first voyage following any considerable amount of repair, when- ever a change has been made in the position of the standard compass ; when there is a change of Captain, unless the new Captain had charge of the vessel during the preceding voyage as Chief Officer.' " In conclusion I must observe that the present state and prospects of the science and practice of the correction of the compass make it impos- sible to offer with confidence any complete set of suggestions as to the 1865.] and on the Meteorological Department. 527 system to be adopted in the Mercantile Marine. This could only be elabo- rated by careful and continued attention directed to the magnetic character of the ships of the Mercantile Marine, their compasses, and the capabilities of its officers ; and I think it must be assumed that no system can be ex- pected to be satisfactory which docs not gradually develope itself under proper supervision. " I have the honour to be, &c. (Signed) " FREDERICK JOHN EVANS, Staff -Commander R.N., Chief Naval Assistant, in charge of Magnetic Department." " The Hydrographer of tht Admiralty." APPENDIX I. Extracted from the Queen's Regulations and the Admiralty Instructions for the government of Her Majesty's Naval /Service. " No iron of any kind is to be placed nor suffered to remain within the distance of seven feet of the binnacle or standard compasses, when it is practicable, according to the size and construction of the vessel, to remove it ; and mixed metal or copper is to be substituted for iron in the bolts, keys, and dowels, in the scarphs of beams, coamings, and head-ledges, and also the hoops of the gaffs and booms and belaying-pins which como within the distance of seven feet of the compasses. " The spindle and knees of the steering-wheels which come within the distance of seven feet of the compasses arc also to be of mixed metal. " Iron tillers, which work forward from the rudder-head, are not to range within seven feet of the compasses ; and in vessels which have iron tillers working abaft the rudder-head, the binnacles are to be placed as far forward from the wheel as may be convenient for the helmsman to steer by. " The boats' iron davits are to be placed as far as may be practicable and convenient from the compasses. "All vertical iron stanchions, such as those for the support of the deck, or for the awnings, &c., and likewise the arm-stands, arc to be kept beyond the distance of fourteen feet from the compasses in use, so far as the size of the vessel will admit. " The binnacles for the steering-compasses are to be constructed upon a given plan, with tops made to take off ; and in order to prevent improper materials from being deposited therein, they are not to be fitted with doors. " For the better preservation of the compasses, in every ship a closet is to be constructed in a dry place, sufficiently large for the reception of the ship's establishment of compasses, and it is to be appropriated to that purpose exclusively, the key being kept by the Masters ; and in order that 528 Correspondence on Magnetism of Ships, [Nov. 30, the spare compass-cards may never be kept with poles of the same name nearest to each other, cases are supplied which will prevent the possibility of their being packed improperly. " All ships are to be swung before sailing from the port where they fit out, and subsequently once in each year, for the purpose of ascertaining the errors of the compasses, also immediately on their arrival on a Foreign Station ; or if there has been any great change in the ship's geographical position since the errors were observed." APPENDIX II. Suggested Rules relating to the Compasses of Iron Merchant Ships. " 1. It is deemed a necessary equipment for every iron ship to be fitted with a Standard or navigating compass, in addition to one or more com- passes for the use of the helmsman. " 2. That so far as the requirements of the ship will permit, special arrangements be made in the course of construction for preparing a place for this compass. " 3. That the Steering- Compasses being subordinate in importance to the Standard Compass, less strict precautions are required for their position ; but it would in all cases be desirable that these compasses (and of necessity the steering-wheel) should not be placed within half the breadth of the ship from the stern-post, rudder-head, and screw-well. " 4. The Standard Compass to be placed at such a height from the deck (not less in any case than five feet) as to command a clear view of the horizon above the bulwarks, and to be out of the way of the sails, booms, &c. " 5. In ships built with their heads near the north, the Standard Com- pass to be placed as far forward as the requirements of the ship will permit. In ships built with their heads near the south, this compass to be placed as near the stern as convenient, subject to the condition that it should not be within half the breadth of the ship from the rudder-head, stern-post, or screw- well. " In ships built near east and west, this compass should not be placed near either extreme of the ship. " 6. The Standard Compass to be as far as possible, and not less than ten feet, from the end of any elongated mass of iron, especially if vertical, such as iron stanchions, capstan-spindles, steam- and stove-funnels, venti- lating-shafts, 0 ; and in ten per cent, of the hundred the average change was 30S<6. The chronometer-room at the new Observatory now being erected at Bidston by the Mersey Docks and Harbour Board will be provided with the means of testing simultaneously between two and three hundred chro- nometers in the way shown by the examples in Table I. It is not neces- sary to test chronometers in this elaborate way on every occasion that they arrive in port, as the corrections for change of temperature remain the same fora long period. The rate may change, as in example 2, Table IV., while the thermal correction remains sensibly the same. When the Greenwich mean time is communicated from an authorized establishment, as is now generally the case in our large sea-ports, the rates of chronometers in the temperature that prevails at the time can be easily ascertained. At present these rates are used on the assumption that the thermal adjustments are perfect. The corrections for change of tempera- ture in Table II. show the improvement which might be effected by testing all chronometers when new, and supplying mariners with Tables of such corrections as may be found to exist. These corrections would require verifying periodically, as in cleaning and repairing timekeepers the thermal adjustment is sometimes altered. December 21, 1865. Sir HENRY HOLLAND, Bart., Vice-President, in the Chair. The following communications were read : — . I. " On the Expansion of Water and Mercury." By A. MATTIIIESSEN, F.R.S. Received December 7, 1865. (Abstract.) Before commencing a research into the expansion of the metals and their alloys, it was necessary to prove that the method I intended to employ, namely that of weighing the metal or alloy in water at different tempera- tures, would yield good and reliable results. To check, therefore, the method, I was led to determine the coefficient of expansion of mercury, and, basing my calculations on Kopp's coefficients of expansion of water, I expected to obtain Regnault's coefficient of expansion of mercury. The coefficient deduced from experiments did not agree with Regnault's ; and being unable to discover any source of error in the method of experimenting, I determined to reinvestigate the matter. The memoir is divided into four parts. 552 Dr. A. Matthiessen on the Expansion [Dec. 21, I. On the determination of the coefficients of the linear expansion of cer- tain glass rods. These rods (1825 millims. long and of 20 millims. diameter) were kindly made for these experiments by Mr. F. Osier. The method used for the determination of their increment in length was that of measuring it with a micrometer-screw, with which a length could be measured with accuracy to 0-001 millim. The rod was placed in a long trough, the one end of the rod resting against a fixed glass tube capped with zinc, the other against another glass tube the other end of which rested against the micrometer-screw. Water was allowed to flow through these glass tubes during the time of observa- tion. The trough being filled with water at ordinary temperature and the position of the screw read off, the water was heated to boiling and another reading taken. The mean of sixteen observations gave for the linear expansion of these rods L,=L0 (1+0-000007290, and therefore for the cubical expansion Y,=V0 (1+0-000021870- II. On the method employed for the determination of the cubical expan- sion of water and mercury. This part of the paper contains a full description of the apparatus em- ployed, and the precautions taken. The method consists of weighing the substances in water at different temperatures, and from the loss of weight in water deducing its volume. For this deduction, the expansion of water at different temperatures is required. III. On the redeterminations of the coefficients of expansion of water. To determine these, pieces of the glass rods (the linear expansion of which had to be determined), ground to the shape of a double wedge, were weighed in water of different temperatures. Three pieces of glass were used (making three Series), the weighings being made at temperatures between 0° and 100°, the whole number of observations being thirty-two. From these it was found that the expansion of water between 4° and 100° may conveniently be expressed between 4° and 32° by the formula V,= 1-0-0000025300 (£-4) + 0-0000083890 (#—4)2-0-00000007173(£-4)3 and between 32° and 100° by V,=0-999695 + 0-0000054724£2-0-000000011260*3. The values calculated from these formulae for the volume occupied by water at different temperatures are given in Table I. from degree to degree together with the differences for each degree. 1865.] of Water and Mercury. TABLE I. 553 •c. Volume of water atT°. Differ- ence per 1°. T . c. Volume of water at T°. Differ- ence per 1°. C. Volume of water at T°. Differ- ence per 1°. 4 5 6 7 8 I "OOOOOO I -000006 1-000028 I -000066 1*000119 0*000006 22 38 53 6q 11 39 40 •006616 •006979 •007351 •007730 •008118 0-000355 363 372 379 388 69 70 72 73 '022050 •022648 •023252 •023861 •024477 0-000598 604 609 6 1 6 622 9 10 ii 12 '3 14 15 16 17 18 2O 21 22 24 26 27 28 29 3° 3* 33 34 35 36 1-000188 1-000271 1-000369 1-000479 1-000604 1-000742 1-000892 1-001054 I '001227 I'OOI4I2 I -001 608 1-001814 I '002029 I '002254 1-002488 1-002731 1-002982 1-003241 1-003507 1-003780 1-004059 I '004345 1-004635 1-004931 1-005249 1-005578 1-005916 I '00626 1 8? 98 no % 150 162 173 185 196 206 215 225 234 243 251 259 266 273 279 286 290 296 318 329 338 0*000345 42 43 44 45 46 47 48 49 So S* 53 54 55 56 59 60 61 62 63 64 165 66 67 68 •008514 •008918 •009331 •009751 •010179 -010614 •011059 •011510 •011969 •012435 •012909 •013391 •013879 •014376 •014879 •015390 •015907 •016432 •016964 •017502 •018047 •018599 •019158 •019724 •020296 1-020874 1-021459 396 404 413 420 428 435 445 45 » 459 466 474 482 488 497 503 5" 5^5 532 538 545 55^ 559 566 572 578 585 74 jl 79 80 81 82 83 84 II 87 88 89 9° 91 92 93 94 95 96 97 98 99 100 •025099 •025727 •026361 •027000 •027646 •028296 •028953 •029615 •030283 •030956 •031634 •032318 •033007 •033701 •034400 •035104 •035813 •036527 •037245 •037969 •038697 •039429 •040166 •040907 •041653 •042404 1-043159 628 634 639 646 650 657 662 668 673 678 684 689 694 699 704 709 714 718 724 728 732 737 741 746 0-000755 IV. On the redeterminatioa of the coefficient of expansion of mercury. The pure mercury was weighed in a bucket in the water at different temperatures. The glass bucket was made from the end of a test-tube (its length being about 20 millims. and width 15 millims.). The expansion of this sort of glass was found to be V,=V0 (1 + 0-0000256G*). Five series were made with mercury ; and its expansions, deduced from the water-expansions given in Table I, were Series I ....... V,=V0 (1 +0-00018150, Series II ....... Vi=V0 (1+0-0001813*), Series III ....... V*=V0 (1 +0-0001808*), V,=V0 -00018080, Series IV Series V ....... V;=-V0 (1 +0-00018160, Mean ____ V,=V0 (1+0-00018 12*), a value closely agreeing with Rcgnault's, namely V =Vo (1+0-00018150- 554 On the Expansion of Water and Mercury. [Dec. 21, Calculating from the five series the coefficients of expansion of mercury, using Kopp's water-expansion (taking the volume at 4°=1), we find as mean V<=Vo (1+0-0001 78*). In the following Table I give the values obtained by different observers for the volumes occupied by water at different temperatures, the volume at 4° being taken equal to 1. TABLE II. T. p*. Desprctz t. Pierre J. Hagen §. Matthiesscn. 4 I -000000 I -000000 i -oooooo I 'OOOOOO i -oooooo 10 •000247 1*000268 •000271 1-000269 •000271 , 15 •000818 1-000875 "000850 •000849 •000892 20 •001690 1-001790 •001717 •001721 •001814 3° •004187 1-004330 •004195 •004250 •004345 40 •007654 1-007730 •007636 •007711 •007730 5° •011890 1-012050 •011939 •011994 •011969 60 •016715 1-016980 •017243 •017001 •016964 70 •022371 1-022550 -023064 •022675 •022648 80 1-028707 1-028850 •029486 •028932 •028953 90 1-035524 1-035660 •036421 1-035715 1-035813 100 1-043114 1-043150 •043777 1-042969 1-043159 Kopp, Despretz, and Pierre used the same method for their determi- nations— that of determining the expansion of water in glass vessels (dilato- meters). Hagen employed the weighing process, but at high temperatures employed no special precautions to prevent the steam condensing on his fine wire ; hence his values at 90° and 100° fall below mine. It will be seen from the foregoing Table that Kopp's values are lower than the others ; and bearing in mind that the coefficient of expansion of mercury, when deduced by means of these, falls below that obtained by Regnault, but when deduced from Despretz's or my own agrees closely with Regnault' 9, we are led to conclude that Kopp's values must be some- what incorrect. * Pcgg. Ann. xcii. 42. t Ann. de Cbim. et de Phys. Ixx. (lre s«r.) 1. } Ann. de Cbim. etde Phys.xiii. (3mc ser.) 325. Calculated by Frankenheim, Pogg. Ann. xcvi. 451. § Abhandlungen d. k. Acacl. der Wisscnsch. zu Berlin, 18G5. 1865.] On the forms of some Compounds of Thallium. 555 II. "On the forms of some Compounds of Thallium." By W. H. MILLER, M.A., For. Sec. R.S., Professor of Mineralogy in the University of Cambridge. Received December 13, 1865. Nitrate of Thallium. Prismatic, 0 1 0, 0 1 1=38° 8'-l ; 1 00, 1 1 0 = 62° 56'-3. Fig. 1 1 0 0, 0 1 1 100, 1 10 1 0 0, 2 1 0 100, 111 1 0 0, 2 1 1 90 0 62 56-3 44 23 68 6-5 51 13 I 1 0, 1 1 1 34 57-5 0 1 1, 0 f 1 103 44 0 1 1, 2 1 1 38 47 1 10, FlO 54 7'4 2 1 0, 2 1 1 28 46 2 1 0, 2 1 0 91 14 01 ,111 21 53-5 1 1 , M 1 43 47 1 1 , 1 fl 93 44-8 1 1 ,TFl 110 5 21 ,211 77 34 21 ,211 75 38 21 , 2l 1 122 28 Observed combinations :— 1 0 0, 1 1 1 ; 1 0 0, 1 1 1, 2 1 1 ; 1 0 0, 0 1 I, 111, 211; 100, 110, 210, 111, 211; 100, Oil, 110, 210, 1 1 1, 2 1 1. No cleavage observable. From tbe observed minimum deviation of the brightest part of the solar spectrum formed by refraction through the faces 100, 110, it appears that the index of refraction of a ray in the plane 001, and polarized in that plane, is about 1-817. The refrangibility of the other ray is greater, its minimum deviation through the same faces being 93° nearly. Sulphocyanide of Thallium. Pyramidal, 0 0 1, 1 0 1 =38° 20'-3. Observed forms :— 1 0 0, 1 1 0, 1 0 1 . 2T 556 Prof. W. H. Miller on the forms Fig. 2. [Dec. 1 0 0, 0 1 0 90 0 1 0 0, 1 1 0 45 0 100, 01 1 90 0 100, 101 51 397 1 I 0, 1 0 1 63 59 101, lOl 76 40-6 101, 01 1 52 2 Observed combinations :— 1 1 0, 1 0 1 ; 1 0 0, 1 I 0, 1 0 1. The crystals are remarkable for the very unequal extension of the faces of the same simple form, and at first sight look as if they belonged to the oblique system. The breadth and thickness of one of the largest crystals were ri and 0*055 millimetre respectively; and of two adjacent laces of the form 1 0 1, one was about eleven times the breadth of the other. The distribution of the large and small faces did not appear to be subject to any law ; so that these crystals cannot be regarded as combinations of large and small hemihedral forms. Twins. Twin face 101. Fig. 3. ioi,10j 180 0 1 1 0, o 1 1 52 4 110,011 -52 4 01 1, 110 75 56 on, no 75 56 ioi,~foi 26 38-8 No cleavage observable. An attempt was made to determine the optical constants of the crystal by observing the minimum deviation of light refracted through a face of the form 110 and one of the opposite faces of the form 100; the latter were, however, so small that the observation could not be made with much accuracy. It appeared that for the ordinary ray polarized in a plane parallel to the line 001, the indices of refraction of red light, of the brightest part of the spectrum, and of violet light were about 2' 1 15, 2- 159, and 2"314 respectively, and that, for the extraordinary ray polarized in the plane 0 0 1, the indices of refraction of red light, the brightest part of the spectrum, and of violet light were about 1-890, 1'973, and 2-143 re- spectively. 1865.] of some Compounds of Thallium. 557 Carbonate of Thallium. The faces which have been observed are all in one zone, and exhibit a symmetry which is compatible with either the prismatic or the oblique system. The crystals probably belong to the prismatic system. They are aggregated in such a manner as to render it very difficult to isolate a single crystal, or to determine the faces which belong to the different individuals of a group of crystals. Observed forms :— 1 0 0, 1 I 0, 2 I 0, 120. Fig. 4. 1 00, 1 1 0 51 28 1 0 0, 2 1 0 32 7 1 0 0, 1 2 0 68 57 1 1 0, 1 1 0 77 4 Twins. Twin face 110. One individual is generally united to each of two others, in this respect resembling the twins of cerussite, aragonite, glaserite, and chrysoberyl. A cleavage has been observed probably parallel to the faces of the form 110; it may, however, be parallel to the faces of the form 100, the com- plexity of the twin crystals being such that it could not be ascertained whether the cleavages observed belonged to one crystal or to two different crystals. I am indebted to Mr. Crookes, the discoverer of thallium, for the crystals of nitrate, sulphocyanide, and carbonate of thallium, above described. •' t» •:*i>'l^ I '. '• . « INDEX TO VOL. XIV. ACETIC ether, action on, of sodium and ethyl iodide, 458 ; sodium and methylic iodide, 462 ; sodium and amyl iodide, 464. ether, synthesis of butyric and ca- proic ethers from, 198. Acid, tricarballylic, soda-salts of, 78. Acids of the lactic series, notes of re- searches on : No. II., 17 ; No. III., 79 ; No. IV., 83; No. V., 191; No. VI., 197; No. VII., 198. , tribasic, on the synthesis of, 77. Acute cestode tuberculosis, on the produc- tion of, 214. Allen (Capt.W.), obituary notice of, i. Aluminium, note on the atomicity of, 74. compounds, preliminary note on, 19. Amylhydroxalic acid, 196. Anniversary Meeting, November 30, 1865, 481. Annual Meeting for election of Fellows, June 1, 1865, 299. Antedon rosaceus, researches on the struc- ture, physiology, and development of, 376. Atacamite, 399. Atmosphere, on the normal circulation and weight of, in the North and South Atlantic Oceans, 345. Atmospheric moisture, its connexion with insolation, 111. Auditors, election of, 458. Australia, on the fossil mammals of: Part II. Description of an almost entire skull of Thylacoleo carnifex, Ow., 348. Babington (T. H), report on forecasts and storm-warnings, 308, 487. Barometric hypsometry, on the corrections for latitude and temperature in, 274. Bastian (H. C.) on the anatomy and phy- siology of the Nematoids, parasitic and free, with observations on their zoologi- cal position and affinities to the Echino- derms, 371. Beale (L. S.), note on a new object-glass for the microscope, of higher magnifying power than any one hitherto made, 35. , on the ultimate nerve-fibres distri- VOL. XIV. buted to muscle and some other tissues, with observations upon the structure and probable mode of action of a ner- vous mechanism, 229. Belavenetz (J.) on the magnetic character of the iron-built armour-plated battery ' Pervenetz ' of the Imperial Eussian navy, 186. Benzol, purification of, 351. Binney (E. W.), a description of some fossil plants, showing structure, found in the lower coal-seams of Lancashire and Yorkshire, 327. Birds, some observations on, chiefly in re- lation to their temperature, 337, 440, 475. , of the air in the air-receptacles and bones of, 441, 475. Board of Trade, communication to the, on the magnetism of ships, 300, 486, 516. , correspondence in reference to meteorological department of, 306, 486, 516. , further correspondence in reference to the magnetism of ships and the meteorological department, 516. Brain, connecting-fibres of the, 129, 134. Bray ley (E. W.), inferences and sugges- tions in cosmical and geological philo- sophy, 120. Brochantite group, on new Cornish mine- rals of the, 86, 392. Bubbles, on, 22. Buckton (G. B.) and Odling (W.), preli- minary note on some aluminium com- pounds, 19. Butyric ether, synthesis of, 200. Ctesium, on the passage of chloride of, into the textures of animals, 422. Calorescence, on, 476. Candidates for election, list of, March 2, 1865, 91. selected, list of, May 4, 1865, 204. Caproic ether, synthesis of, 203. Carbonate of thallium, 557. Carpenter (W. B.), researches on the structure, physiology, and development of Antedon (Comatula, Lamk.) rosaceus, 376. 2u 560 Catalogue of scientific papers, notice of, 48^. Cayley (A.), addition to the memoir on Tschirnhausen's transformation, 641. , a supplementary memoir on the theory of matrices, 543. Cells, on the movements in, 231. Chasles (M.),Copley Medal awarded to,493. Chemical affinity, on the influence of quantity of matter on, 144. change, on the laws of connexion be- tween the conditions of, and its amount, 470. Child (G.), further experiments on the production of organisms in closed vessels, 178. Chronometers, on the testing of, for the mercantile marine, 548. Ciliary action, 232. Circulation, artificial, experiments on, 364. Colloid acid, on a, a normal constituent of human urine, 1. , compounds of, 6. , physiological relations of, 8. Compass, effect of particular arrangements of iron in a ship on the, 114, 500, 516. in iron ships, on the correction of, 527. Contractility, on, 231. Medal awarded to Michel Chasles, Cosmical and geological philosophy, in- ferences and suggestions in, 120. Council, list of, 513. Croonian Lecture, May 11, 1865.— On the ultimate nerve-fibre distributed to muscle and some other tissues, with ob- servations upon the structure and pro- bable mode of action of a nervous me- chanism, 229. Crystalloid substances, on the rapidity of the passage of, into the vascular and non-vascular textures of the body, 63. Crystalloids, on the rate of passage into and out of the vascular and non-vascular textures of the body, 220, 400. Cureton (Eev. W.), obituary notice of, i. Dale (R. S.), hydride of heptyl from azelaic acid, 466. Davy (J.), some observations on birds, chiefly in relation to their temperature, with supplementary additions on their bones, 337, 440, 475. Dawes (Rev. W. R.) admitted, 319. De la Rue (W.), Stewart (B.), and Loewy (B.), researches on solar physics : Series!. On the nature of solar spots, 37. , Series II. On the behaviour of sun-spots with regard to increase and diminution, 59. Diethylated acetone, 460. Digitaline, on the application of physiolo- gical tests for, 270. Discriminants, on a theorem concerning, 336. Disk, on the heating of, by rapid rotation in vacuo, 339. Donoughmore (Earl of) admitted, 134. Dove (H. W.) on meteorological observa- tions, 317. Dufferin (Lord) admitted, 204. Echidna hystrix, on the marsupial pouches, mammarv glands, and mammary foetus of the, 106. Electric light, note on the invisible radia- tion of, 33. Electrical resistance, report on the new unit of, 154. Electricity, atmospheric, observations of, at Windsor, Nova Scotia (No. II.), 10. Ellis (A. J.), introductory memoir on plane stigmatics, 176. on the corrections for latitude and temperature in barometric hypsometry, with an improved form of Laplace's formula, 274. Entozoa, cystic, on the production of, in the calf, 214. , nematode, chemical examination of the fluid from the peritoneal cavity of,69. , on the existence of glycogen in the tissues of, 543. Equations, on Newton's rule for the dis- covery of imaginary roots of, 268. Ethers, notes of synthetical researches on, (No. I.), 198, 458. Ethylic amyloethoxalate, 193. amylohydroxalate, 192. diethacetone carbonate, 459. Evans (F. J.) and Smith (A.) on the magnetic character of the armour-plated ships of the Royal Navy, and on the effect on the compass of particular ar- rangements of iron in a ship, 114, 485. Everett (J.D.), account of observations of atmospheric electricity at King's College, Windsor, Nova Scotia (No. II.), 10. Fagge (C. H.) and Stevenson (T.) on the application of physiological tests for certain organic poisons, and especially digitaline, 270. Fellows deceased, list of, 481. elected, list of, 482. Fibre, striated muscular, on the develop- ment of, 374. Flower (W. H.) on the commissures of the cerebral hemispheres of the Marsu- pialia and Monotremata, as compared with those of the placental mammals, 71. , reply to Professor Owen's paper " On zoological names of characteristic INDEX. 561 parts and homological interpretations of their modifications and beginnings, especially in reference to connecting- fibres of the brain," read before the Royal Society March 23, 1865, 134. Foetus, mammary, of the Echidna hystrix, 106. Forecasts and storm-warnings, report on, 308, 487. Fossil plants found in the lower coal-seams of Lancashire and Yorkshire, descrip- tion of, 327. Foster (M.) on the existence in the tissues of certain entozoa, Fox (Sir C.) on the size of pins for con- necting flat links in the chains of sus- pension bridges, 139. Fox (W.) on the development of striated muscular fibre, 374. Frankland (E.) and Duppa (B. F.), notes of researches on the acids of the lactic series : — No. II. Action of zinc upon a mixture of iodide of ethyl and oxalate of methyl, 17 ; No. III. Action of zinc- ethyl upon ethylic leucate, 79 ; No. IV. Action of zinc upon oxalic ether and the iodides of methyl and ethyl mixed in atomic proportions, 83 ; No. V. Action of zinc upon a mixture of ethyl oxalate and amyl iodide, 191 ; No. VI. Action of zinc upon amylic oxalate and ethylic iodide, 197 ; No. VII. Action of zinc upon a mixture of amyl oxalate and amyl iodide, 198. , notes of synthetical researches on ethers : No. I. Synthesis of butyric and caproic ethers from acetic ether, 198. , synthetical researches upon ethers — synthesis of ethers from acetic ether, 458. Galton (F.) appointed a member of me- teorological committee, 541. Gas, liquefied hydrochloric acid, on the properties of, 204. Gassiot (J. P.), description of a rigid spectroscope, constructed to ascertain whether the position of the known and well-defined lines of a spectrum is con- stant while the coefficient of terrestrial gravity under which the observations are taken is made to vary, 320. Geometry of space, on a new, 53. Glyceri-tricarballylate of baryta, 78. Glycogen, on the existence of, 'in the tissues of certain entozoa, 543. Gore (G.) admitted, 319. — on the properties of liquefied hydro- chloric acid gas, 204. Grant (R.) admitted, 541. Gray (G. R.) admitted, 458. Green (J. H.), obituary notice of, i. Gun-cotton, notice of utility of, 492. Gurney (H.), obituary notice of, v. Guthrie (F.) on bubbles, 22. Harcourt (A. V.) and Esson (W.) on the laws of connexion between the condi- tions of a chemical change and its amount, 470. Harley (Dr. G.) admitted, 319. Harrison (J. P.), lunar influence on tem- perature, 223. Hartnup (J.) on testing chronometers for the mercantile marine, 548. Heliotrope, on two new forms of, 297. Heptyl, hydride of, from azelaic acid, 466. High Asia, temperatures of the atmosphere and isothermal profiles of, 547. Hirst (T. A.) on the quadric inversion of plane curves, 91. Horner (L.), obituary notice of, v. Howard (L.), obituary notice of, x. Huggins (W.) admitted, 319. on the spectrum of the Great Nebula in the Sword-handle of Orion, 39. Hulke (J. W.) on the chameleon's retina, a further contribution to the minute anatomy of the retina of amphibia and reptiles, 378. Hydrocarbons, researches on, 164. of the series CnH2,,+2 (No. II.), re- searches on, 464. Hydrochloric acid gas, on the properties of, 204. Indian meteorology, numerical elements of, 111. Trigonometrical Survey, account of the base-observations made at Kew Ob- servatory, 425. Infusoria, on the development of certain, 546. Insolation, and its connexion with atmo- spheric moisture, 111. Jenkin (F.) admitted, 319. , report on the new unit of electrical resistance proposed and issued by the committee on electrical standards ap- pointed in 1861 by the British Associa- tion, 154. Jones (H. Bence) on the rapidity of the passage of crystalloid substances into the vascular and non-vascular textures of the body, 63. on the rate of passage of crystalloids into and out of the vascular and non- vascular textures of the body, 220, 400. Langite, 87, 393. Laplace's formula, improved form of, 274. Life, inquiry into the possibility of re- storing, in warm-blooded animals, in certain cases where respiration, circula- 562 INDEX. tion, and signs of organic motion appear to have ceased, 358. Light, electric, invisible radiation of, 33. Lithium, experiments on the rate of pas- sage of, into and out of the animal tex- tures, 406; through the human body, and into and out of the crystalline lens, 410, 415. , on the presence of, in solid and liquid food, 222, 417. , on the rate of passage of solutions of, into the textures of animals, 420. , salts of, experiments with, on ani- mals, 402. Livingstone (D.) admitted, 204. Lunar influence on temperature, 223. M'Donnell (R.) admitted, 475. Magnetic character of armour-plated ships, 114,186,500. disturbances at Kew, 1858-64, coin- cidence of with variation of sun-spots, 490, 512. variation, terrestrial decennial period of, 491, 513. Magnetical observations, taken at the Col- lege Observatory, Stonyhurst, 65. Magnetism of ships, communication to the Board of Trade on, 300, 516. Marcet (W.) on a colloid acid, a normal constituent of human urine, 1. , chemical examination of the fluid from the peritoneal cavity of the nema- tode entozoa, 69. Mars, further observations on, 42. Marsupialia, on the commissures of the cerebral hemispheres of the, 71. Maskelyne (N. S.) on new Cornish mine- rals of the Brochantite group, 86, 392. Matrices, supplementary memoir on the theory of, 543. Matter, on the influence of quantity of, over chemical affinity, 144. Matthiessen (A.) on the expansion of water and mercury, 551. Mercury, on the expansion of, 551. Metals, on the elasticity and viscosity of, 289. Meteorological department of Board of Trade, correspondence in reference to, 306, 486, 516. observations, suggestion for syste- matic scheme of, 489. Meteorology, numerical elements of In- dian: Series II., Ill ; Series III., 547. Methylated acetone, 463. Methyl-hexyl, 465. Microscope, note on a new object-glass for, 35. Miller (W. H.) on two new forms of heliotrope, 297. on the forms of some compounds of thallium, 555. Monotremata, on the commissures of the cerebral hemispheres of the, 71. Mylne (W. C.), obituary notice of, xii. Myology, human, additional varieties in, 379 Nematoids, parasitic and free, on the ana- tomy and physiology of, 371. , observations ou their zoological posi- tion and affinities to the echinoderms, 373. Nerve-fibres distributed to muscle, &c., 229. Nervous mechanism, structure, and pro- bable mode of action of, 251. Nitrate of thallium, 555. Nova Scotia, observations of atmospheric electricity in, 10. Obituary Notices of deceased Fellows :— Capt. W. Allen, i. Rev. Dr. W. Cureton, i. J. H. Green, i. Hudson Gurney, v. Leonard Horner, v. Luke Howard, x. W. C. Mylne, xii. Major-General J. E. Portlock, xiii. Dr. Archibald Robertson, xvii. Giovanni Antonio Amedeo Plana, xvii. Heinrich Rose, xix. Friedrich Georg Wilhelm Struve, xx. Object-glass for microscope, on a new, 35. Oceanic statistics, suggestion for scheme of, 488. Organisms in closed vessels, further expe- riments on the production of, 178. Orion, on the spectrum of the great ne- bula in the sword-handle of, 39. Ornithorhynchus, eggs of, 111. Ostrich tribe, structure and development of the skull of the, 112. Owen (R.) on the marsupial pouches, mammary glands, and mammary foetus of the Echidna hystrix, 106. on zoological names of characteristic parts and homological interpretations of their modifications and beginnings, especially in reference to connecting- fibres of the brain, 129. on the fossil mammals of Australia : Part II. Description of an almost en- tire skull of Thylacoleo carnifex, Ow., 343. Paris, H.R.H. the Count of, admitted, 268. , • , notice of election of, 490. Parker (W. K.) admitted, 319. on the structure and development of the skull of the ostrich tribe, 112. Pendulums, an account of the base-obser- vations made at Kew Observatory with INDEX. 563 the, to be used in the Indian Trigono- metrical Survey, 357, 425. Perrenetz, iron-built armour-plated bat- tery, on the magnetic character of, 186. Phillips (J.), further observations on the planet Mars, 42. , notices of the physical aspect of the sun, 46. , notice of the surface of the sun, 476. , notice of a spot on the sun, observed at intervals during one rotation, 479. Photoheliograph at Kew, observations with, 492, Plana (Baron G. A. A.), obituary notice of, xvii. Plane curves, on the quadric inversion of, 91. Plane stigmatics, introductory memoir on, 176. Pliicker (J.) on a new geometry of space, 53. Poisons, cardiac, addition to the list of, 274. , on the application of physiological tests for, 270. Portlock (Major-General J. E.), obituary notice of, xiii. President's Address, 482. Prestwich (J.), Eoyal Medal awarded to, Radiation from a revolving disk, prelimi- nary note on, 90. Rainey (G.) on the influence of quantity of matter over chemical affinity, as shown in the formation of certain double chlorides and oxalates, 144. Receipts and payments, statement of, 514. Respiration, artificial, experiments on, 360. Retina, on the chameleon's; a further con- tribution to the minute anatomy of the retina of amphibia and reptiles, 378. Richardson (B. W.), an inquiry into the possibility of restoring the life of warm- blooded animals in certain cases where the respiration, the circulation, and the ordinary manifestations of organic mo- tion are exhausted or have ceased, 358. Robertson (Dr. A.), obituary notice of, xvii. Rose (H.), obituary notice of, xix. Royal Medal awarded to J. Prestwich, 497; to Archibald Smith, 498. Rubidium, on the passage of chloride of, into the textures of animals, 421. Russell (W. H. L.) on symbolical expan- sions, 329. on the summation of series, 332. Samuelson (J.) on the development of certain infusoria, 546. Schlagintweit (H. von), numerical elements of Indian meteorology : — Series II. In- solation, and its connexion with atmo- spheric moisture, 111 ; Series III. Tem- peratures of the atmosphere, and iso- thermal profiles of High Asia, 547. Schorlemmer (C.), researches on the hy- drocarbons of the series Cn H2B+2, 164. 464. Sextactic points of a plane curve, on the, 349. armour-plated, on the character of, 114,186. Sidgreaves (Rev. W.), monthly magnetical observations taken at the College Ob- servatory, Stonyhurst, in 1864, 65. Silver, on the passage of sulphate of, into the textures of animals, 423. Simonds (J. B.) and Cobbold (T. S.) on the production of the so-called " Acute Cestode Tuberculosis " by the adminis- tration of the proglottides of Tania mediucanellata, 214. Simpson (M.) on the synthesis of tribasic acids, 77. Skull of the ostrich tribe, on the structure and development of, 112. Smith (A.), Royal Medal awarded to, 498. Solar autographs, 492. physics, researches on : Series I., 37 ; Series II., 59. spots, on the nature of, 37. Southern telescope, notice of, 483, 503. Space, on a new geometry of, 53. Spectroscope, description of a rigid, 320. Spectrum of the great nebula in the sword-handle of Orion, 39. Spottiswoode (W.) on the sextactic points of a plane curve, 349. Stenhouse (J.), preliminary notice of the products of the destructive distillation of the sulphobenzolates, 89. — , products of the destructive distilla- tion of the sulphobenzolates (No. I.), Stewart (B.) and Loewy (B.), an account of the base-observations made at Kew Observatory with the pendulums to be used in the Indian Trigonometrical Survey, 357, 425. and Tait (P. G-.), preliminary note on the radiation from a revolving disk, 90. , on the heating of a disk by rapid rotation in vacuo, 339. Stonyhurst, magnetical observations at, 65. Strontium, on the passage of chloride of, into the textures of animals, 424. Struve (F. G. W.), obituary notice of, xx. Sulphobenzolates, preliminary notice on the products of the destructive distilla- tion of, 89 ; products of the destructive distillation of (No. I.), 351. Sulphobenzolic acid, preparation of, 351. Sulphocyanide of thallium, 555. 564 Summation of series, on, 332. Sun, notices on the physical aspect of the, (Part I.), 46. , notice of the surface of, 476. , notice of a spot on, observed at in- tervals during one rotation, 479. Sun-spots, on the behaviour of, with re- gard to increase and diminution, 59. , variation of, coincidence of mag- netic disturbance with, 491. Suspension bridges, on the size of pins for connecting flat links in the chains of, 139. Sylvester (J. J.) on Newton's rule for the discovery of imaginary roots of equa- tions, 268. on a theorem concerning discrimi- nants, 336. Symbolical expansions, on, 329. lania mediocanellata, on the production of acute cestode tuberculosis by admi- nistration of the proglottides of, 214. Temperature, lunar influence on, 223. of birds, observations on, 337, 440, 475. Tennyson (A.) admitted, 541. Thallium, on the passage of the sulphate of, into the textures of animals, 423. , on the forms of some compounds of, 555. Thomson (W.) on the elasticity and vis- cosity of metals, 289. Thylacoleo carnifex, description of an al- most entire skull of, 343. Toronto, magnetic observations at, 491, 513. Toynbee (H.) on the normal circulation and weight of the atmosphere in the North and South Atlantic Oceans, so far as it can be proved by a steady meteorological registration during five voyages to India, 345. Tribasic acids, on the synthesis of, 77. Tricarballylate of lime, 78. of copper, 78. of lead, 79. Tricarballylic ether, 77. amylic ether, 78. Trigonometrical Survey of India, note on, Tschirnhausen's transformation, addition to the memoir on, 541. Turner (Lord Justice) admitted, 134. Tyndall (J.), note on the invisible radia- tion of the electric light, 33. on calorescence, 476. Unit of electrical resistance, on the new, 154. Vice-Presidents appointed, 541. Villiers (Rt. Hon. C. P.) admitted, 476. Waringtonite, 88, 397. Warm-blooded animals, restoration of life in, experiments on, 358. Water, on the expansion of, 551. Williamson (A. W.), note on the atomicity of aluminium, 74. Wood (J.), additional varieties in human myology, 379. Zinc, action of, upon a mixture of iodide of ethyl and oxalate of methyl, 17; upon oxalic ether and the iodides of methyl and ethyl, 83 ; upon a mixture of ethyl oxalate and amyl iodide, 191 ; upon amjlic oxalate and ethylic iodide, 197 ; upon amyl oxalate and amyl iodide, 198. Zincethyl, action of, upon ethylic leucate, 79. Zoological names of characteristic parts, &c., 129, 134. END OF THE FOURTEENTH VOLUME. Printed by TAYLOB and FRANCIS, Red Lion Court, Fleet Strnet. EEEATA. Page 178, line 4 from the bottom, for George Child, M.D. read Gilbert W. Child, M.D. „ 228, „ 12, for 618 read 619. „ 318, „ 7 from bottom, for recognize read fail to recognize. „ 445, „ 23, for eat read sweat. „ 446, „ 2, „ th read their. ,, 449, ,, 2, ,, Yellowhammer read Yellow ammer. „ 455, „ 25, „ yellow-hammer read yellow ammer. „ 456, „ 11, „ Brains read Brain. „ — „ 25, „ exterior read exclusive. „ — ,, 32, ,, formed read freed. „ — „ 33, „ or read a. „ 475, „ 5 from bottom, and page 513, line 3 from bottom, for Paul E. Count de Strzlecki read, Paul E. Count de StrzelecM. „ 540, ,, 24, for receptionf read reception of. NOTICE TO THE BINDEE. In this Volume the following pages are to be cancelled :— 153 & 154, 203 & 204, 299, 357 & 475. OBITUARY NOTICES OF FELLOWS DECEASED BETWEEN 30-TH Nov. 1863 AND 30-TH Nov. 1864. Capt. WILLIAM ALLEN entered the Navy in 1805. At the passage of the Dardanelles, by Sir John Duckworth, he served on board 'The Standard ; ' and afterwards took part in the expedition against Java. He was engaged in the Niger exploration under Capt. Trotter in 1841, and in 1848 published an account of the Voyage, in two volumes. In 1855 he brought out another work on the " Dead Sea, and the Overland Communi- cation with the East," in which he recommended the cutting of a canal from the Mediterranean to the Dead Sea. He was an active member of the Royal Geographical Society, and was elected into the Royal Society in 1844. He died in January, aged seventy-one. In the Rev. Dr. WILLIAM CURETON, Canon of Westminster, ancient lite- rature has lost one of the ablest of Syriac scholars. His 'Corpus Ignatianum,' an edition of an ancient Syriac version of the Epistles of St. Ignatius, with commentaries, published in 1845, established his reputation as an Orien- talist, and became the occasion of a spirited controversy which was carried on for some years among students of ancient texts. This was followed by an edition of a palimpsest of portions of Homer, discovered in a convent in the Levant, and in 1855 by ' Spicilegium Syriacum,' in both of which Dr. Cure ton exhibited profound and accurate scholarship. He was con- tinuing his researches into old Syriac versions of St. Matthew's Gospel at the time of his decease ; and, considering how valuable were the services he rendered to that department of literature, the accident by which those services were interrupted is the more to be deplored. Dr. Cureton was born in 1808. About two years before his death, which took place at Westbury, Shropshire, on June 17, 1864, he sustained so severe a shock from an accident to a railway-train in which he was tra- velling, that his health remained permanently impaired. He was educated at Christ Church, Oxford, and was ordained a priest in 1834 ; in 1847 he was appointed Chaplain in Ordinary to the Queen, and in 1849 was pre- ferred to a canonry of Westminster, and therewith to the rectorship of St. Margaret's. Besides these ecclesiastical employments, he held for a short time the place of Sublibrarian to the Bodleian Library ; in 1837 he became Assistant-keeper of the MSS. in the British Museum, and was afterwards appointed one of the Trustees of the Museum on the part of the Crown. He was elected a Fellow of the Royal Society in 1838. JOSEPH HENRY GREEN was born in London, on the 1st of November, 1791, and died at Hadley, Middlesex, on the 13th of December, 1863. Mr. Green's father was a merchant of high standing in the City of Lon- don, and his mother was a sister of Mr. Cline, the eminent surgeon. His school education was begun in this country, but completed in Germany, where, accompanied by his mother, he spent three years, chiefly in Hanover. VOL. xiv, b At the age of eighteen he was apprenticed to his uncle, Mr. Cline, and en- tered on the study of medicine at St. Thomas's Hospital, of which Mr. Cline was surgeon. In 1813 he married Miss Anne Eliza Hammond. This lady, who survives him, was the daughter of Mr. Hammond, surgeon at Southgate, and sister of an early friend and fellow student. In 1815 Mr. Green became a member of the College of Surgeons, and was soon afterwards appointed Demonstrator of Anatomy at St. Thomas's Hospital. "While in this office he published a ' Dissector's Manual,' which bore advantageous comparison with the books of the same kind then in use. In the meantime Mr. Cline had retired from St. Thomas's, and was suc- ceeded by his son Mr. Henry Cline, on whose early death, in 1820, Mr. Green was appointed Surgeon to that Hospital, and Lecturer on Surgery in the Medical School, in conjunction with Sir Astley Cooper, who withdrew from the joint office in 1825. The advantageous position in which Mr. Green was now placed, and his own merit, speedily gained for him the confidence of his profession and the public. In 1824 he was appointed Professor of Anatomy to the Royal College of Surgeons ; in 1825 he was elected a Fellow of the Royal Society (in later years he served on the Council). Also in 1825 he received the appointment of Professor of Anatomy to the Royal Academy, and in the latter part of that year delivered the first of a long succession of annual courses on Anatomy in its relation to the Fine Arts. Ere now, too, he had acquired a considerable and increasing share in the private practice of his profession. Respecting the Lectures at the College of Surgeons, which formed one comprehensive course distributed over four years, Professor Owen, who heard them delivered, thus writes to Mr. Simon* : — "For the first time in England the comparative anatomy of the whole animal kingdom was de- scribed, and illustrated by such a series of enlarged and coloured diagram as had never before been seen. The vast array of facts was linked by refer- ence to the underlying Unity, as it had been advocated by Oken and Carus. The Comparative Anatomy of the latter was the text-book of the Course. Green illustrated, in his grand course, Carus rather than Hunter ; the dawning philosophy of Anatomy in Germany, rather than the teleology which Abernethy and Carlisle had previously given as Hunterian, not knowing their master." Of Mr. Green's lectures at the Royal Academy (where he retained his professorship till 1852), Mr. Simon, who attended several of the courses, thus expresses himself: — " His teaching at the Royal Academy, like all his teaching, was characterized by a very deep-going and comprehensive treat- ment of his subject. He recognized, of course, that the details of anatomy * The facts, and in some places the language, of this notice have been taken from a biographical memoir prefixed to Mr. Green's posthumous work (to be afterwards referred to) by its editor, John Simon, Esq., F.R.S., Mr. Green's friend and pupil. The passages in inverted commas are taken from that source. (even of mere artistic surface-anatomy) could not be adequately spoken of, much less conveyed, in the six formal lectures which he had annually to deliver. ...... Not indeed that he omitted to survey, or surveyed other- wise than admirably, the composition and mechanism of the human body ; and perhaps no mere anatomist ever taught more effectively than he what are the bodily materials and arrangement which represent the aptitude for strength, equipoise, and grace, or what respective shares are contributed by bone, muscle, and tegument to the various visible phenomena of form and gesture, attitude and action. But to this he did not confine himself. Specially in the one or two introductory or closing lectures of each course, but at times also by digression in other lectures, he set before his hearers that which to them, as artists, was* matter of at least equal concern — the science of interpreting human expression and appreciating human beauty. His discourses on these subjects were very deeply considered. Necessarily they were of wide philosophical range. And they were enriched with num- berless illustrative references to the history of Art, and to the master-works of ancient and modern sculpture and painting." On the establishment of King's College in 1830, Mr. Green was nomi- nated Professor of Surgery, and continued to hold the Professorship till 1836, when he resigned it (on retiring to' live in the country), and was elected a Member of the Governing Council of the institution. Of his surgical lectures it is stated on the best authority that the technical instruc- tion imparted, perfect as it was, was by no means their sole excellence ; they had also a moral aim, and were admirably fitted to exert a favourable influence on the habits of thought and future professional character of his young hearers. In 1 835 Mr. Green was elected on the Council of the College of Surgeons, and in 1846 appointed to the Court of Examiners. In 1840 and 1847 he delivered the Hunterian Oration ; in 1849-50 and again in 1858-59 he was President ; in 1853 he exchanged his post of Surgeon to St. Thomas's for the honorary appointment (then first made) of Consulting Surgeon to that institution; and on the creation, by the Medical Act of 1858, of the General Council of Medical Education and Registration, he was chosen by the College of Surgeons to be its representative in the new body. Two years later, when the post of President of the Medical Council became vacant by the retirement of Sir Benjamin Brodie, the Council unanimously elected Mr. Green to the office ; and he continued in it, with the warmest regard and confidence of its members, for the remaining three years of his life. Mr. Green thus attained to the foremost rank in his profession, and came to occupy with universal assent its highest public offices ; but the contem- plation of his professional and public career would convey a wholly inade- quate notion of his intrinsic mental tendencies and pursuits, and the scope of his intellectual activity. From his early years he had a bent towards the study of abstract philosophy in its largest and highest sense ; and to gratify this inclination he, in the summer of 1817, found time to spend a few months in Berlin to go through a private course of reading on philosophy with Professor Solger, on whom, as well as on Ludwig Tieck whom he had met in London, his amiable disposition and "noble eagerness for knowledge" made a most favourable impression. Probably about this time also he became acquainted with Coleridge, and contracted an admi- ration of his philosophy ; soon afterwards, at any rate, a close inti- macy grew up between them, which continued during the rest of Cole- ridge's life. "Invariably he spent with Coleridge — they two alone at their work— many hours of every week, in talk of pupil and master. And so year after year,' he sat at the feet of his Gamaliel, getting more and more insight of the teacher's beliefs and aspirations, till, in 1834, two events occurred which determined the remaining course of his life. On the one hand, his father died, and he became possessed of amply sufficient means for his profession to be no longer needful to his maintenance. On the other hand, Coleridge himself died. And the language of Coleridge's last will and testament, together no doubt with verbal communications which had passed, imposed on Mr. Green what he accepted as an obliga- tion to devote, so far as necessary, the whole remaining strength and earnestness of his life to the one task of systematizing, developing, and establishing the doctrines of the Coleridgian philosophy." Influenced by these circumstances he withdrew from private practice and resigned his professorship at King's College. Then, too, he gave up his London house and retired to reside at Hadley ; and although he did not relinquish his interest in the practical aspects of his profession or his care for the amendment of its institutions, continuing still to take an active share in the government of the College of Surgeons, and finally presiding in the Medical Council, yet all such occupations and objects then became secondary in his mind to the one object of his philosophical studies and the fulfilment of the task he had undertaken. With this purpose Mr. Green entered upon the widest possible range of study ; for he deemed it necessary to test the applicability of the Colerid- gian system to all branches of methodized human knowledge. Accordingly, in the twenty-seven years of life that remained to him, " Theology, Ethics, Politics and Political History, Ethnology, Language, ^Esthetics, Psycho- logy, Physics and the Allied Sciences, Biology, Logic, Mathematics, Pa- thology— all were thoughtfully studied by him in at least their basial principles and metaphysics, and most were elaborately written of as though for the divisions of some vast encyclopaedic work." Mr. Green took advantage of the public discourses which on more than one occasion he was called on to deliver, to make known his opinions on the relation of the Coleridgian philosophy to the study of science and the learned professions. Of these there have appeared in print his Address oil the opening of the Medical Session at King's College in 1832, the Hun- terian Oration for 1840, entitled "Vital Dynamics," and that for 1847, with the title "Mental Dynamics." But as years advanced, certain threatening bodily ailments warned him that it was time to utilize in a systematic and communicable form, at least a part of the fruits of his vast preparatory labour ; and he accordingly determined to complete a work which should give in system the doctrines, especially the theological and ethical doctrines, which he deemed most distinctively Coleridgian ; and to this he devoted what in effect proved to be the whole available remainder of his life. The result is a work in two volumes published under the editorship of Mr. Simon. The first volume is devoted to the general principles of philosophy, while the second is entirely theological, and espe- cially aims at vindicating a priori (on principles for which the first volume has contended), the essential doctrines of Christianity. The mental qualities and character of Mr. Green will be found ably de- lineated in Mr. Simon's memoir; suffice it here to say that his life, both private and public, was a life of benevolence, probity, truth, and honour. Mr. HUDSON GURNEY, who died at the advanced age of ninety-five, was one of the well-known Norfolk family of that name, members of the Society of Friends, and through his wife was connected with the Barclays of Ury. He was for many years a leading Member of the House of Commons, dis- tinguished by the favour he showed to men of letters, and the literary and art collections which he formed. In 1811 he published a poem, 'Cupid and Psyche,' based on the Golden Ass of Apuleius. He was elected a Fellow of the Royal Society in 1818. LEONARD HORNER, the third and youngest son of Mr. John Homer, linen-merchant in Edinburgh, was born on the 17th of January, 1785. It was but natural that with an early enthusiasm for science he should have become a geologist ; for in Edinburgh at that time Button, Hall, Playfair, and a band of zealous followers, by observation in the field and by experi- ment in the workshop, were gathering materials for a new philosophy of geology, and were waging a keen warfare with the partizans of Werner. The year of Mr. Homer's birth was that in which Button's famous excursion to the granite of Glen Tilt was made. He was three years old when that philosopher unfolded his new theory to the Royal Society of Edinburgh, and he had grown up to be a High School boy of ten years of age when the immortal 'Theory of the Earth' was published. At that time, indeed, according to his own confession, he was a thoughtless youth with no special liking for study, and a vague passion for the sea. But these scientific discussions had not come to a close when he grew up to be able to understand and take an interest in them, and their influence is to be traced throughout his life. He entered the University of Edinburgh in 1 799, and attended the lectures of Playfair on Mathematics. In 1802 he was study- ing moral philosophy under Dugald Stewart, and chemistry with Hope ; and it, was when fairly launched into these studies that his mind took that bent towards natural science by which it was marked during the rest of his life. " From that time," he writes, " began a new state of mind. I took an interest in the subject, bought apparatus, made experiments, and de- stroyed many of my mother's towels. I took a particular interest in mineralogy, began to make a collection of specimens, cultivated acquaint- ance with some fellow students who had the same turn, and read Playfair's ' Illustrations of the Huttonian Theory,' of which I became a worshipper, having heard it well expounded by Dr. Hope." He was too young to have personal intercourse with Hutton, though he tells how he used to hear much in his own family of the " ingenuity, acuteness, and even light- hearted playfulness " of that philosopher. But he became attached to the Professor of Mathematics, to whom sixty years afterwards he referred from the chair of the Geological Society as his " venerable friend the able and eloquent Play fair." At the age of nineteen Mr. Horner left Edinburgh to become partner in a branch of his father's business, which it was proposed to carry on in London. His elder brother Francis was already rising to eminence in the House of Commons ; so that Mr. Horner soon found himself in the midst of a large circle of friends, among whom were not a few of note in science and literature. Two years afterwards he married Miss Lloyd, daughter of a landed proprietor in Yorkshire, and took a house in London. His love for geology, however, was not quenched by the claims of business, for we find him, the year after his marriage, joining the newly-founded Geological Society. Nor did he become an inactive member. In 1810, the second year after his election, he was chosen one of the Secretaries of the Society, and from that time down almost to the very day of his death, he continued one of its most zealous and unwearying members. In 1815 he found himself under the necessity of returning to Edinburgh to take a personal superintendence of his business there. Two years after- wards his brother Francis, with whom he had journeyed to Italy in a vain search for health, died full of promise. When Mr. Horner had recovered from the blow of this sad loss, his active mind sought new scope for itself in the organization of political meetings, wherein the young Whiggism was 'developed, for which Edinburgh afterwards came to be so noted. In this, as in many other features of his life, Mr. Horner showed the practical and methodical character of his mind, as well as his social disposition ; for these meetings were not arranged without exciting much keen opposition and political feeling. His residence in Edinburgh was marked by the success of another project — one of themostwidelyuseful of all his schemes for thebenefit of his fellow-men. In March 1821, happening to observe some watch- makers at work, he was led to inquire whether they ever received any mathematical education. On being told that they did not, and that, though anxious to obtain such instruction, they could not afford to pay for it, the idea occurred to him to found a school for the training of mechanics in those branches of science which would aid them in their daily work. Hence arose the Edinburgh School of Arts. Mr. Homer laboured hard for the success of this scheme, and he lived to see it completely successful. He acted as Secretary of the School for the first six years ; and during all the rest of his life, even though no longer resident in Edinburgh, he continued to take an active interest in the institution and in its prominent students. He several times gave donations of books to the library, and in 1858 in- vested a sum of money for an annual prize of three guineas. The useful- ness of this school has been great. About seven hundred young men are entered annually as students in mathematics, chemistry, or natural philo- sophy, and receive at small cost instruction which would otherwise lie be- yond their reach. Several of the foremost engineers of the present day have been students there. It was in remembrance of this and similar kinds of philanthropic activity, that Lord Cockburn styled Mr. Horner " one of the most useful citizens Edinburgh ever possessed." Mr. Horner left Edinburgh in the year 1827 to assume the office of Warden in the University of London, a post at which he laboured for four years, until his failing health led him to seek a retreat with his family on the banks of the Rhine. At Bonn he had leisure to renew his old love for mineralogical and physical geology ; and in making himself acquainted with the geological structure of the district, he at the same time formed a life- long friendship with some of the most eminent men of science and learning there. On his return to England in 1833 he was appointed one of a Commission to inquire into the employment of children in the factories of Great Britain. The Report of this Commission gave rise to the Factory Act, under which Mr. Horner was made one of the Inspectors of Factories, an office which, through good and ill report, he laboriously and conscien- tiously filled for nearly thirty years. His zeal for the interests of the women and children in the factories often placed him in conditions of great delicacy, yet, notwithstanding opposition and disparagement, he continued his exertions, and earned the gratitude of the workers, while he was at the same time rewarded by finding an ever-increasing number of millowners who acknowledged the benefits of the Act which it was his duty to enforce. During these busy years, however, he never lost or relinquished his interest in the progress of science, and more especially of Geology. No face was more constantly seen at the Meetings of the Royal and Geological Societies than that of Mr. Horner. He had become a Fellow of the Royal Society in 1813, and in various years served on the Council. In 1845 he took an active part in the reform of the Society, whereby the mode of Election of new Members was modified. In the year 1857 he was nomi- nated Yice-President. In the Geological Society he took a still more prominent part. Besides reading papers at its Meetings, he became in 1846 its President, an office which he again filled in 1860. He was unremitting in his attention to all that might in any way further the interests or usefulness of the Society. He worked with his own hands in the Museum, arranging and cataloguing its stores of specimens ; and he carried on this task at intervals np to within a short period of his death, labouring often to the verge of his physical strength. To his suggestion is due the publication of the Quarterly Journal of Papers read at the Society's Meetings, one of the most important undertakings of this Society. When Mr. Homer at last resigned the office of Inspector of Factories, although now seventy-five years of age, he still remained so full of youthful energy, that he looked forward hopefully to spend yet a few years in more undivided attention to his favourite science. Unable longer for the toils of out-of-door geology, he resumed with fresh zeal the arrangement of the Geological Society's Museum, anxious that its stores of rock-specimens should be classified in such a form as in the end to afford a comparative series of the different rocks throughout the globe. The failing health of his wife interrupted this task, and induced him to spend the winter of 1861-62 at Florence. There, as at Bonn, he found a ready welcome into the cultivated and learned society of that city. While there, he occupied himself with translating from the Italian Villari's * Life of Savonarola,' and published it in England a few months afterwards. Mrs. Homer's health, however, which had continued a source of anxiety to him, at last gave way, and she died as the family was on the point of returning to England, When M r Horner came back to London, his friends saw with concern that this great sorrow had told only too plainly upon his health. His strength began to fail, but his energy seemed as fresh as ever. He returned to his labours among the collections of the Geological Society, and day after day he was found poring over dusty specimens, describing and cataloguing them with the same perseverance and even enthusiasm which he had shown from the beginning. A few months after his return from Italy, viz. during the summer of 1862, he paid his last visit to his native city. Never was his welcome warmer. He came at the time when the schools were passing through their public examination previous to dismissal for the autumn holydays — the High School where he himself had been educated, and the Academy which, with Lord Cockburn, he had founded. He attended the examinations, addressed the boys, presented some of the prizes, and showed at the end of his long life the same deep interest in education and in the pursuits of youth. His old Edinburgh friends, too — now a yearly de- creasing number — vied with each other in their attention to the venerable philanthropist. Returning from Scotland to London, he fixed upon the 1 5th of March, 1864, as the day when he should leave England to revisit the grave of his wife at Florence. But before that day came round a cold seized him, followed by extreme weakness, and he died calmly on the 5th of March. Physical geology was the branch of science to which Mr. Horner more specially devoted himself. The influence of his early acquaintance with Playfair and the Huttonian geologists at Edinburgh is visible throughout his scientific course. He began the study imbued with the prevailing ideas regarding the importance of mineralogical geology ; and his first papers — that on the Malvern Hills, and that on Somersetshire — may be taken as characteristic specimens of the mineralogical system of treatment by which the geology of the early part of this century was marked. But though from the state of the science at that time (1811—1815) it was not to be expected that he should succeed in unravelling the complicated geo- logical relations of the different rocks, it is yet interesting to mark how he carried with him the spirit of careful observation in which Playfair had trained him, and how readily he saw among the hills of England proofs of the truth of the Huttonian system. During his active life he had few opportunities of doing much in field-geology. When he found a little leisure in his retreat at Bonn, he at once reverted to his favourite science, and the results of his sojourn were given to the Geological Society in a paper on the Geology of the Environs of that town. During the same interval of rest he was led, in the true spirit of the Huttonian school, to institute a series of experiments on the quantity of solid matter suspended in the water of the Rhine, with the view of arriving at some " measure of the amount of abraded stone transported to the sea, there to constitute the materials of new strata now in progress of formation." These researches have become classic in the' history of geology. Fifteen years later a similar kind of inquiry greatly interested him when Lepsius called attention to certain sculptured marks in the valley of the Nile ; and in 1851 he obtained from the Royal Society a grant of money for the purpose of excavations to be made in the Nile alluvium. To link together the earliest human with the latest geological history seemed to him an object worthy of earnest prosecution. After four years of exploration, carried on according to a plan drawn up and sent out by him to Egypt, Mr. Homer published the results of his researches in the 'Philosophical Transactions' for 1855. His presidential addresses to the Geological Society were devoted to a survey of the progress of geology. They are remarkable for the sympathy which they show for views far in advance of those in which he had himself been trained. But it is not by the number or character of his writings that Mr. Horner's influence among the scientific men of his day is to be estimated. His age and experience, his association with the early days of British geology, his political connexions, his sound judgment and careful business habits, joined to his excellent social qualities, gave him a position which none can now fill. And he retained his influence in no small measure from the singular fervour and youthfulness of his mind. Instead of clinging to old methods and beliefs as one of his years and early predilections might have been expected to do, he was found ever ready to receive and sympa- thize with new developments of truth, and to uphold the cause of progress in all departments of science. Even at the last, when he read his final address to the Geological Society, he pleaded boldly for the high antiquity of the human race in opposition to popular prejudice on this subject, and claimed for the speculations of Mr. Darwin the thoughtful consideration of all lovers of truth. Mr. Homer's death severed a link closely and visibly connecting the geologists of today with the early masters of the science in this country, and closed a long and honourable life, full of all kindliness, and ever devoted to the welfare of his fellow men. g LUKE HOWARD was born in London in 1772, a date which carries us back to the early years of the reign of George III., and opens a long vista of history in which great political changes are rivalled by the grandest discoveries of modern science. Luke Howard's parents, members of the Society of Friends, sent their son to a country school in North Oxfordshire, where, as he was accus- tomed to say in after life, " he learnt too much of Latin grammar and too little of anything else." But having even then an observing eye, he began to notice the appearances of the sky and forms of clouds ; and his inclina- tion towards meteorology appears to have been fixed by his impressions of the remarkable atmospheric and meteoric phenomena which, as those ac- quainted with the history of meteorology will remember, characterized the year 1783. From school young Howard went as apprentice to a chemist at Stock- port, which was then a quiet country town. In this situation he devoted his spare hours to the course of self-improvement which he had already begun, and acquired that knowledge of French, botany, and the principles of chemistry, which were so useful to him in after years. The quickening effect produced on his mind by the works of Lavoisier he described as "like sunrise after morning moonlight," an effect which has been felt by many a student. In 1798 he entered into partnership with "William Allen, whose repu- tation as a manufacturing chemist has long been recognized. This con- nexion, however, was brought to an amicable close a few years later, and Howard, taking as his portion the laboratory at Plaistow, applied himself to the business therewith connected, and to his favourite scien- tific pursuits. Making use of his observations of natural phenomena, he wrote a paper " On the Modifications of Clouds," and read it at a meeting of the Askesian Society, of which he and his friend Allen were members. This paper, as he himself tells us, " the result of his early boyish musings, enriched by the observations of many a walk or ride, morning and evening, to or from his day's work at the laboratory," was published in 1803, and made known the author's name and ability to a wider circle. The Aske- sian was not a publishing Society ; otherwise Luke Howard might have been better known than he is as a pioneer in departments of science besides meteorology. " I know," writes one of his friends, " that one or more of his papers related to atmospheric electricity, and another was an antici- pation of the cell-theory, as regards the structure and functions of plants, founded on microscopic investigations." Many, if not all, the articles on meteorology in * Rees's Cyclopaedia/ were written by Luke Howard. He contributed a series of papers to the 'Athenaeum,' embodying the results of his meteorological observations from the year 1806; and these he published in two volumes (1818-20), under the title " Climate of London, deduced from Meteorological Observa- tions made in the Neighbourhood." This, republished in 1833, in three volumes, has become one of our standard works on meteorology. Luke Howard was elected a Fellow of the Royal Society in 1821. From that time his reputation as a meteorologist increased, and eminent persons in many parts of the world opened a correspondence with him, which, in some instances, became the initiation of a lasting friendship. Although the increasing perfection of philosophical apparatus has super- seded some of his methods of observation, there can be no doubt that his labours imparted more of a scientific character to meteorology than it had ever received before. His classification of the clouds is the one still recog- nized at all observatories, and remains an evidence of the quick eye he had for form and colour, and of the daily labour which was to him a labour of love. One who knew him well in the latter part of his life, says, " Those who lived with him will not soon forget his interest in the appearance of the sky. "Whether at morning, noon, or night, he would go out to look around on the heavens, and notice the changes going on. His intelligent remarks and pictorial descriptions gave a character to the scene never before realized by some. A beautiful sunset was a real and intense delight to him ; he would stand at the window, change his position, go out of doors, and watch it to the last lingering ray ; and long after he ceased, from failing memory, to name the ' cirrus,' or ' cumulus,' he would derive a mental feast from the gaze, and seem to recognize old friends in their outlines." Sharing in the active beneficence so characteristic of the Society of Friends, Luke Howard readily aided endeavours for the religious and moral as well as the material welfare of the community. Not least im- portant among these was the seeking to mitigate by pecuniary means the sufferings of the Germans during the campaigns immediately preceding the first abdication of Napoleon. In Ackworth School — a well-known esta- blishment of the Friends — he took a lively interest; and to participate the more directly therein, as well as to offer hospitality to the annual visitors to the school, he bought the Ackworth Villa estate in 1823, making it his summer residence, and Tottenham his winter residence, during the greater part of his life. In 1796 Luke Howard married Mariabella Eliot, a member of the same Society with which he was himself connected. Of their family of seven children two sons only survived their parents. About his eightieth year he was much enfeebled by alarming attacks of illness ; and the death of his wife following, after a union of fifty-six years, added sorrow to his xh weakness. Henceforward his life was a subdued waiting for the end. He died at Tottenham on the 21st March, 1864. A portrait of Luke Howard, bequeathed to one of his friends, is even- tually to be added to the Royal Society's collection. Besides the works above mentioned, he published — Essay on the Modifications of Clouds, 1832 ; Seven Lectures on Meteorology, 1837 ; a Cycle of Eighteen Years in the Seasons of Britain, &c., 1842 ; Barometrographia — Twenty Years' Variation of the Barometer in the Climate of Britain, 1847 ; Papers on Meteorology, 1850-54 ; and The Yorkshireman, a religious and literary Periodical, in 5 vols., 1833-37. WILLIAM CHADWELL MYLNE was born in London, on the 6th of April, 1781, and died on the 25th of December, 1863. His father, Robert Mylne, F.R.S., a native of Edinburgh, and the representative of a long line of Scotch architects, commenced his career in London in 1759 by building Blackfriars Bridge, and held the appointment of Engineer to the New River Water Works, to which his son, the subject of this notice, suc- ceeded in 1810. Mr. Mylne may be said to have been from his cradle bred an engineer. When a boy only sixteen years of age he was engaged with the younger Mr. Golborne in the Fen country in staking out the lands for his father's great scheme of the Eau Brink Cut, an undertaking which, through oppo- sing interests, was defeated at that time, but was eventually carried out by Mr. Rennie in 1817. Subsequently he was occupied on his father's well- known project, the Gloucester and Berkeley Ship Canal, seventy feet in width ; and he was generally engaged in assisting his father in the largest professional practice of that day. Succeeding at thirty years of age to the sole conduct of the New River Works, Mr. Mylne had before him an arduous and responsible office. The supply of water to London had hitherto been solely derived from the New River and London Bridge Works ; but the rapid extension of the metro- polis led to the establishment of new companies, which gave rise to serious contests, and for some years involved them in a ruinous competition. Mr. Mylne's ability and energy were soon tried in carrying out extensive changes in the New River Works. The old wooden main pipes, which up to 1810 were the principal conduits for the passage of water, were found insuffi- cient to stand the requisite pressure, and it was deemed expedient to sub- stitute pipes of cast iron. This improvement was effected at a cost of nearly half a million sterling ; and the whole was satisfactorily accom- plished under Mr. Mylne's judicious management. Notwithstanding the constant and \inremitting engagements of the New River business, Mr. Mylne was occupied in considerable engineering prac- tice, particularly in the Fen country, carrying out Sandys Cut, with several other important drainage works. Combining also the hereditary profes- sion of an Architect, he was engaged in bridge-building, and in the alte- rations and extensions of many private mansions. Among his works, the single-arched iron bridge over the River Cam, at St. John's College, Cam- bridge, has been much admired ; and the church of St. Mark's, Clerken- well, met with considerable approval at the period of its erection, forty years since. Mr. Mylne in later years was much occupied in Government references, and acted as surveyor for fifty years to the Stationers' Company, having succeeded his father in that office. He was also extensively engaged before Parliamentary Committees on Water, Dock, and Drainage Works, and was consulted in continental works of similar character. From the date of his entering on the direction of the New River Works to his retirement, two years before his death — a period of fifty years — he had the satisfaction to witness a very great advance in the income of the Company, and a great extension of their works, consequent on the increased demand caused by the further growth of the metropolis and awakened attention to its salubrity. In 1852 new works were undertaken to the extent of three quarters of a million sterling, and executed by him, with the assistance of his son, R. W. Mylne, F.R.S. Mr. Mylne was a man of a peculiarly kind and conciliatory disposition, a peace-maker in all professional strife, of strict integrity and high honou- rable feeling. He was for many years the guiding hand, as Treasurer, to the Society of Engineers styled " Smeatonians," in which, as in all other Asso- ciations, he won the respect, esteem, and almost affection of those with whom he was connected. His retiring disposition caused him seldom to take part in scientific discussions ; but he took a keen interest in all ques- tions of progress, and during his long career judiciously availed himself of the opportunities offered him of adopting the new inventions of the age. Mr. Mylne was elected a Fellow of the Royal Society on the 16th of March, 1826. Major-General JOSEPH ELLISON PORTLOCK, son of Captain Nathaniel Portlock, a distinguished officer of the Royal Navy, was born at Gosport in September 1/94. He received his early education at a school in his native town and at Tiverton, from which he went to the Royal Military Academy at Woolwich. In 1813 he took his first commission in the Royal Engineers, and was sent in the following year to Canada, where he remained actively employed in military service or exploring expeditions until 1822. He was present at the siege of Fort Erie ; and, on the retire- ment of the troops, he constructed the lines and bridge-head at Chippewa, at which Sir Gordon Drummond made his successful stand, and saved Upper Canada. In 1824, on the extension of the Ordnance Survey to Ireland, Lieut. Portlock was one of the officers first selected by Colonel Colby to take part in the work ; and his earliest duty in connexion therewith, conjointly with Lieuts. Drummond and Larcom, lay in working out the preliminaries of what has since grown into first-rate importance as the Topographical Department. The task at that time was beset by difficulties, which the progress of physical and mechanical science has since removed : the pre- paration of the base-apparatus, the construction of astronomical and other surveying-instruments, the contriving of signals by lamp and heliostat, and the training of sappers for their special duties had to be undertaken under the disadvantage of newness. But at that time the Duke of Wellington was Master- General of the Ordnance ; and supported by him, Colonel Colby carried out his plans in full efficiency. In 1825 the first detachments were removed to Ireland, and the first trigonometrical station was taken up on Divis Mountain, near Belfast. There the first signals and observations with lamp and heliostat were attempted, and, to the satisfaction of the originators, proved completely successful. This was Lieut. Portlock's start on the trigonometrical branch of the survey, of which he shortly became the senior, and eventually sole officer. In addition to scientific skill and accuracy, great personal endurance was required in carrying on the observations. In 1826 the camp on Slieve Donard, 2800 feet above the sea, was more than once blown down by the violence of the wind. Colonel Colby was seriously injured by a fall while climbing from the observatory to his tent ; and communication with the country below involved both difficulty and danger. Yet " Portlock," we are told, " held out to the last. For some weeks he was the only officer remaining ; but he struggled on, and brought the operations to a successful close." In the following year, while Colonel Colby was measuring the base on the shore of Lough Foyle, Lieut. Portlock, with Lieut. Larcom, carried out the observations at seven hill-stations, regardless of season and weather. In 1828, and for some years afterwards, he performed the work single- handed, observing with the great theodolite from mountain after mountain till the principal network of triangulation was complete, and the Irish system was, by means of the lamp and heliostat signals, united to that of Britain. In addition, care had to be taken for the direction of the secondary triangulation for the details of the survey, and for the rectification of errors and the discrepancies that were sure to occur at the junction of the separate districts. For this the whole had to be combined under one general system ; and this additional labour Lieut. Portlock undertook while still on the mountains. He carried it on afterwards at his office in Dublin ; and so well did he direct these secondary operations, that, after the parties became used to the work, the surveying went on at the rate of three million acres a year. The horizontal survey involved the necessity of an elaborate vertical survey and calculations for altitude. The altitudes were deduced at first from the sea, by actual levelling from it to bases of altitude, and from them transferred, by angles of elevation and depression, to the summit of every XV hill and station, at distances averaging a mile asunder ; and on this the minor levelling of the detail survey depended. This also was ultimately generalized into a system by Lieut. Portlock, and by him furnished regu- larly and rapidly. In fulfilling this purpose, he personally carried a line of levelling across the island from the coast of Down to the coast of Donegal, and caused several lines to be observed in other places. In this way a more general and homogeneous system of altitudes was obtained than had ever before been attempted. It supplied the data for the paper on Tides by the Astronomer Royal, published in the ' Philosophical Transactions.' In all this we see a character conspicuous alike for ability and energetic perseverance ; but among its other elements, there was one which may be properly noticed here— the praiseworthy example he set to the men under his command. They felt that with him they were in the hands of some- thing superior to themselves in intellect and acquirements, and they im- proved in a marked degree in the duties of the survey, in intelligence, and the habit of obedience. " They needed only encouragement, no coercion, and they rapidly acquired knowledge ; to all of which I can testify," writes one of Portlock' s brother officers ; " and I am sure it is the expe- rience of the whole corps, more perhaps than any other in the army, that when officers study the characters of their men, and use in governing them the knowledge so acquired, they are amply rewarded by the result, and need no coarser discipline." Sergeant Manning, who worked under Lieut. Portlock through the whole period of his service on the Irish survey, was chosen as the non-commissioned officer best fitted to take charge of a party sent in 1848 to the Cape of Good Hope, to verify, under direction of Mr. (now Sir Thomas) Maclear, the base measured by Lacaille nearly a century before. Of the great value of the Irish survey in connexion with the geology, archaeology, statistics, and industrial resources of Ireland, this is not the place to speak. Suffice it to say that when the time came for drawing up a Report on the subject, Lieut. Portlock proved himself not less able as a geological than as a geodetical observer. His separate Report on the Geology of Londonderry has been pronounced by high authority to be " a perfect model for fidelity of observation and minute attention to pheno- mena." It is safe to affirm that the name of Portlock will ever be most honourably associated with the history of the Ordnance Survey of Ireland. In 1843 Captain Portlock was ordered to Corfu on the ordinary duties of his corps. In the comparative leisure which he then enjoyed he wrote papers on the geology and natural history of the island, and on professional subjects. Some of these were published in the Reports of the British Association, the Annals of Natural History, and Journal of the Geological Society. The Association voted him a grant " for the Exploration of the Marine Zoology of Corfu," the results of which he embodied in two papers subsequently published. In these again we have evidence of his activity of mind and accuracy of observation. Recalled to England in 1847, Major Portlock was stationed first at Portsmouth, and afterwards, as Lieut. -Colonel, at Cork. From this time the literature of his profession and scientific study engaged'much of his attention. The annual volumes published by the British Association con- tain papers from his pen ; and besides contributions to the Professional Papers of the corps, he wrote the articles " Geology and Geodesy," " Gal- vanism," "Heat," "Palaeontology," andan Appendix on Gun-Cotton for the Aide-memoire, and the Treatise on Geology in Weale's Rudimentary Series. Others of his papers appear in the Journal of the Geological Society of Dublin, of which Society he was four times President. In 1851 Lieut.-Col. Portlock was appointed Inspector of Studies at the Royal Military Academy, Woolwich, in which place he helped forward measures for improving the scientific character of the system of education, and increasing its efficiency generally ; and during this period he wrote the articles " Cannon," " Fort," " Gunnery," and revised the article " War" for the 8th edition of the ' Encyclopaedia Britannica,' besides translating for the new series of Professional Papers a work on Gunpowder (from the French), and a treatise on Strategy (from the Italian). He wrote also a memoir of his former chief, Major-General Colby, a publication honourable alike to the subject and the author. To all this must be added the two Addresses delivered by him as President of the Geological Society in 1857 and 1858, which, in the words of an eminent authority, are characterized by " faithful and elaborate research." After resigning his appointment at Woolwich, and holding the command for a few months at Dover, Major-General Portlock became in 1857 a Member of the Council of Military Education, in whose proceedings, as might have been expected, he took an active and earnest part. His sen- timents with regard to the objects in view may be gathered from a memo- randum drawn up by one of his colleagues, who writes, " General Port- lock's opinions on the questions presented to him as a Member of the Council were in all cases those of the most forward advocates of educa- tion. He looked upon competition as the great principle upon which public appointments should be made, nor did he shrink from the inevi- table social results which such a change would involve. Education, combined with good morals, he regarded as constituting a paramount claim to the rank of gentleman. He was therefore a warm advocate of the system of open competition as applied to the elections into the Royal Military Academy of Woolwich ; nor did he share the apprehension, which has been very frequently expressed, of a consequent lowering of the social position of the officers of the two great scientific corps. The weakness and infirmities of advancing years were borne by General Portlock with a spirit not less calm and patient than that which animated him through the hardships of the Ordnance Survey. He retired to Lota, a pleasant spot near Dublin, and there died on the 14th February, 1864. He was elected a Fellow of the Royal Society in June 1837, and was a member of other metropolitan and provincial Societies. The honorary degree of Doctor of Laws was conferred on him by Trinity College, Dublin, in 1857." This brief notice of one who was for twenty-seven years an honour to the Society, may be fittingly closed with a few words of affectionate testi- mony by a brother officer, to whose Memoir we are indebted for much of the foregoing. " The characteristics which shone forth in Portlock during his well-spent life," writes Major-General Sir Thomas Larcom, "whether as a soldier, a geographer, or a geologist, were — undaunted courage in facing difficulties, Spartan endurance and invincible perse- verance in overcoming them. Endowed, when in the zenith of his career, with a frame and nerves of iron, he exhibited such a vast power of con- tinuous labour, that he achieved every object he had in view ; while great ability, and a pure love of knowledge, were in him guided and governed by the highest sense of honour and moral rectitude." Dr. ARCHIBALD ROBERTSON was born at Cockburnspath in Scotland, on the 3rd of December, 1 789. He studied medicine at Edinburgh, and in 1808 entered the Naval Medical Service. After some years of active employment in Europe arid America, he on the termination of the war resorted again to Edinburgh for the further prosecution of study, and took his degree of M.D. in that University in 1817. He then settled as a physician in Northampton ; and although for more than a twelvemonth he did not receive the encouragement of a single fee, he held on to the position he had taken, and was soon rewarded by large and lucrative employment, his success being promoted and assured by his being in 1820 elected Physician to the Northampton Infirmary. After a long and pros- perous professional career, and the acquisition of a handsome independence honourably earned, he in 1853 resolved to withdraw himself from the labour of active practice. He accordingly left Northampton, and passed the rest of his life in retirement in the west of England. Dr. Robertson was a man of considerable literary accomplishment, and, before his time became engrossed by practice, he was in the habit of writing literary articles in some of the journals and reviews of the day. He con- tributed two short articles on professional subjects to Forbes's 'Cyclopaedia of Medicine.' He was elected a Fellow of the Royal Society on the llth of February, 1836. Both as a physician and as a member of society, Dr. Robertson was highly esteemed. His death took place at Clifton, on the 1 9th of October, 1864. GIOVANNI ANTONIO AMEDEO PLANA, descended from an ancient and distinguished family of Guarene in Piedmont, was born at Voghera, on the 8th of November, 1781. In 1800 he entered the Polytechnic School of Paris, where he so greatly distinguished himself that, on the 23rd of May, 1803, he was appointed Professor in the Artillery School of Alessandria. On the 28th of November, 1809, he presented to the Academy of Turin a paper, entitled "Equation de la courbe formee par une lame elastique quelles que soient les forces qui agissent sur la lame," the first of a series of papers offered to the same Academy, far too numerous to be recorded in the present notice. On the 15th of March, 1811, on the recommendation of Lagrange, he obtained the Professorship of Astronomy in the Uni- versity of Turin, and on the 5th of March, 1813, became Director of the Observatory. After the Restoration, the king, Victor Emmanuel I., who took a personal interest in the progress of astronomy and frequently sent for Plana to explain various celestial phenomena, augmented the income of the Observatory, and transferred it from the house of the Academy to a better situation on the west tower of the north face of the Palazzo Ma- dama. During the years 1821, 1822, 1823 he was associated with Carlini in the operation of measuring an arc of parallel in Savoy and Piedmont. The results were published in 1825, under the title "Observations geode- siques et astronomiques pour la mesure d'un arc de parallele moyen." In 1828 the authors received from the Institute the Lalande prize for the astronomical part of their joint work. In 1832 he published his ' Theorie du mouvement de la Lune,' in three large quarto volumes. This he re- garded as the most important of all the labours of his life. For this work the Copley Medal was awarded to him in 1834, and the Gold Medal of the Astronomical Society in 1840. In announcing the latter award, Sir John Herschel, President of the Society, made the following quotation from the " Discours preliminaire " of the ' Theorie de la Lune' — "Je n'ai pu me faire aider par personne ; j'ai du traverser seul cette longue chame des calculs, et il n'est pas etonnant si, par inadvertence, j'ai omis quelques termes qu'il fallait introduire pour me conformer a la rigueur de mes propres principes," — adding, " When we look at the work itself there seems something awful in this announcement." In 1822, on the occasion of the appearance of his " Mdmoire sur les mouvements des fluides qui recouvrent une sphero'ide a peu pres spherique," he was elected a Corresponding Member of the Institute, and in 1860 one of the eight Foreign Associates. In December 1851 he became President of the Royal Academy of Turin. He was elected Foreign Member of the Royal Society in 1827. He received from his own king the title of Baron, and was created a Senator on the formation of the Senate in 1848. He delighted in the classic poets, and was not more remarkable for the accuracy and elegance of his mathematical investigations than for the pre- cision of his style in writing. He was in the habit, it is said, of bestowing extraordinary care on the composition and correction of his works. On the 6th of January, 1864, he read a paper before the Royal Academy of Turin, entitled " Memoire sur les formules du mouvement circulaire, et du mouvement elliptique libre autour d'un point excentrique par 1'action d'une force centrale." This was his last work. He died at Turin on the 20th of January, 1864, leaving a widow (Lagrange's niece) and a daughter. XIX The death of his only son, on the 27th of March, 1832, called forth the expression of grief which concludes the Introduction to the 'Theorie de la Lune.' HEINRICH ROSE was born on the 6th of August, 1795, at Berlin, where his father, son of the discoverer of the fusible alloy known by his name, was Pharmacist and Assessor of the Superior Medical College. His father died in 1807, leaving behind him a widow and four young boys. H. Rose studied Pharmacy first in Dantzic, where he experienced the horrors of a siege, and nearly lost his life by typhus fever. He served in the campaign of 1815, together with his three brothers, of whom one is Professor Gustav Rose, the distinguished Mineralogist of Berlin. On the conclusion of the war he continued his studies in Berlin, working in Klaproth's labo- ratory during the summer of 1816. In September 1816 he entered the Pharmacy of Dr. Bidder of Mitau. About the end of 1819 he went to Stockholm, where he worked for a year and a half in the laboratory of Ber- zelius, who recommended him to devote himself to the teaching of che- mistry as a profession. On quitting Stockholm he resided for some time at Kiel, where he wrote his Dissertation " de Titanio ejusque connubio cum oxygenio et sulphure," and took the Degree of Doctor of Philosophy. In the summer of 1822 he obtained the sanction to become a private teacher in the University of Berlin, and began a course of lectures on prac- tical analytical chemistry in the autumn of the same year. He was ap- pointed Extraordinary Professor in 1823, and Ordinary Professor of Che- mistry in 1835. He was elected a Member of the Berlin Academy in 1832, Foreign Member of the Royal Society in 1842, Corresponding Mem- ber of the Institute in 1843, and was invested with the Prussian order of pour le merite. His memoirs on inorganic chemistry and chemical analysis, a department in which he stood unrivalled, to the number of nearly, if not quite, two hundred, are contained principally in Gilbert's and Poggendorff's ' Annalen.' The results of his researches in analytical chemistry are embodied in his ' Handbuch der analytischen, Chemie,' which came out in one volume in 1829. A second edition, in two volumes, was published in 1831, a fourth in 1838, a fifth in 1850, the sixth (so thoroughly revised that it should be regarded as a new work) was published in French, at Paris, in 1861. In forming an estimate of the labour expended in preparing this voluminous treatise, it must be remembered that each precept is the result of an expe- riment (frequently of a series of experiments) made by the author. During the last years of his life he was engaged in writing an elementary treatise on analytical chemistry, about thirty sheets of which were printed during his lifetime. For this work also a large number of experiments were made in his laboratory. His activity and industry increased with advancing age. A year before his death he was heard to exclaim, " I have at most only a few years to live, and so much remains to be done!" During the latter part of his life his only recreation was a long walk taken late in the evening, in all weathers, throughout the year. He was the first person in all Ger- many who established a class of working pupils. He received them in his private laboratory without fee, providing at his own cost most of the appa- ratus and all the reagents they required. He was spared the pain of feeling the approach of bodily and mental infirmity. He lectured in full possession of all his faculties only eight days before his death, and he was confined to his bed only seven days. On the 27th of January, 1864, he asked for writing-materials to correct some proof sheets, saying that he felt well, and that he could now leave his bed. That afternoon he died, of inflammation of the lungs. He left behind him a widow, his third wife, and a grandchild, the daughter of Professor Karsten. Her mother, H. Rose's only child, died some years since. FRIEDRICH GEORG WILHELM STRUVE was born at Altona on the 15th of April, 1793. He was the fourth son of Dr. Jacob Struve, Direc- tor of the High School of Altona. His mother was the daughter of Pas- tor Stinde, Chaplain to Peter III., Emperor of Russia. In order to avoid the French conscription, he went in 1808 to the University of Dorpat, where his elder brother Carl was a Classical Lecturer. At first he devoted himself to Philology, a study in which he delighted to the end of his life. He supported himself partly by private tuition in the family of M. de Berg, and partly on some pecuniary assistance afforded him by the Uni- versity on the recommendation of the elder Parrot, who had discovered Struve's promise of future eminence. In 1811, after taking his first de- gree in Philology, he commenced the study of Astronomy under Huth, who permitted him the free use of the few instruments contained in the Observatory at that time; and in August of that year he verified by obser- vation the conclusions of Sir "William Herschel respecting the angular mo- tion of the two stars composing Cas or. In the autumn of 1813 he took the degree of Doctor of Philosophy, the title of his thesis on that occasion being " De geographica specula Dorpatensis positione." In November 1813 he was appointed Extraordinary Professor of Mathematics and Astronomy, and, after the death of Huth, Ordinary Professor, and Director of the Observatory. During the years 1816-19 he surveyed and mapped Livonia at the request of the Economical Society of that Province, the only instrument employed by him in the survey being a 10-inch sextant by Troughton. In 18121 the Observatory of Dorpat was supplied with a meridian-circle by Reichenbach and Ertel, and in 1824 with an equatorially mounted re- fractor, of 9 Paris inches aperture and 160 Paris inches focal length, by Fraunhofer. The principal results of the observations made by Struve at Dorpat during the years 1814-1838 are given in the works entitled "Ob- servationes astronomicse institutes in specula Dorpatensi, 1817—1839," " Catalogus 795 stellarum duplicium, 1822," " Catalogus novus stella- rum duplicium et multiplicium, 1827 " [in the introduction to this XXI work it is incidentally noticed that on one occasion lie had observed unin- terruptedly for eight hours in a temperature of — 25° C.], " Stellarum duplicium et multiplicium mensurse micrometricae, 1 837," " Stellarum fixarum imprimis compositarum positiones mediae, deductae observatioiiibus meridianis a 1822 ad 1843 in specula Dorpatensi, 1852," " Beobachtungen des Halley'schen Cometen bei seinem Erscheinen im Jahre 1835, auf der Dorpater Sternwarte angestellt, 1839." In the spring of 1839 he left Dorpat to assume the Directorship of the Observatory of Pulkowa, built in accordance with his own plans, and fur- nished with instruments contrived and executed under his own directions. An account of the building and instruments is given in his " Description de 1'Observatoire central de Pulkowa, 1845." In 1843 he published his " Catalogue de 514 etoiles doubles et multiples, &c., et Catalogue de 256 etoiles doubles principales ou la distance des composantes est de 32" a 2' &c.," and " Sur le coefficient constant dans 1'aberration des etoiles fixes deduit des observations qui ont etd executees a 1'observatoire de Poulkova." In 1847 he published " Etudes d' Astronomic stellaire." Struve devoted a portion of the summer for many years to the vast un- dertaking of measuring an arc of the meridian of 25° 20' from Fuglenaes on the Arctic Ocean, lat. 70° 40', to Ismail on the Danube, lat. 45° 20'. This work may be considered the principal labour of his life : he was assisted in it by General Tenner and the astronomers Selander and Hansteen. It lasted thirty-seven years, and was completed in 1853» An account of the measurement is given by Struve in " Breitengradmessung in den Ostseeprovinzen Russlands ausgefiihrt und bearbeitet in den Jahren 1821 bis 1831," in " Expose* historique des travaux executes jusqu'a la fiu de 1'annee 1851, pour la mesure de Tare du mcridien, &c., 1860," and in "Arc du me'ridien de 25° 20' entre le Danube et la mer Glaciale, 1860." Besides the works already mentioned, he is the author of many separate treatises, and of papers in Bode's ' Jahrbuch,' the ' Zeitschrift ' of von Lindenau and Bohnenberger, von Zach's ' Correspondence Astronomique,' and the 'Bulletins' and ' Memoires ' of the Imperial Academy of St. Petersburg. In 1858 he was attacked by a severe illness, for which rest from work and travelling were prescribed. These remedies, however, failed to remove the consequences of his malady. In 1862 he retired from the post of Director of the Pulkowa Observatory, and was succeeded by his son O. \V. Struve. He then went to live with his family in St. Petersburg, occupying the remainder of his life with the subject of double stars. On the 4th of November he felt Indisposed ; his strength failed rapidly ; and he died on the morning of November the 23rd, 1864. He was elected Foreign Member of the Royal Society in 1827, and in the same year one of the Royal Medals was awarded to him for his ' Cata- logus novus Stellarum duplicium.' He received the Gold Medal of the Royal Astronomical Society in 1826, "for his important researches on the subject of multiple stars." His name appears in the list of Associates in the first volume of the ' Memoirs of the Astronomical Society.' In iy33 he was elected Corresponding Member of the Institute. Struve married twice ; he had twelve children by his first wife, of whom eight survive, and eight by his second wife, now his widow, of whom four survive. Much of the present notice has been derived from a very comprehensive sketch of Struve's life and labours in the Proceedings of the Astronomical Society, by the Rev. C. Pritchard. T. MAR 9 19 H L718 v.H 'hysical & Applied So. eriab Royal Society of London Proceedings PLEASE DO NOT REMOVE CARDS OR SLIPS FROM THIS POCKET UNIVERSITY OF TORONTO LIBRARY