SjfcStf JOURNAL OF NATURAL PHILOSOPHY, CHEMISTRY, AND THE ARTS. VOL. XXII. 3iUu0ttatcD toitfj €ngta\3ings. BY WILLIAM NICHOLSON. ttauummaammm* LONDON. PRINTED BY W> STRATFORD, CROWN COURT, TEMPLS BAR * FOR W. NICHOLSON, CHARLOTTE STREET, BLOOMSBURY; AND SOLD BY J.STRATFORD, No. IK', Holbgun- IIiil. 1809. PREFACE. X HE Authors of Original Papers and Communications in the present Volume are, the Rev. E. J. Burrow, A. M. ; Sir Thomas Clarges, Bart.; P. Barlow, Esq.; Mr. John Farey; Mr. William Skrimshire, jun. ; Dr. Thomas Stewart Trail! ;• A Correspondent; Richard Greene, Esq. P.R. M.S. E. ; Mr. B. Cook; Mr. James Scott ; G. K. M. ; Philochemicus ; Mr. de Luc ; E, F. G. H. ; S. N. ; Sir George Cayley, Bart. ; T. ; Mr. Charles Hayter; Mr. W. Wel- don; W. Saint, Esq.; Arthur Aikin, Esq. ; Thomas Young, M.D. F. R. S. ; John Gough, Esq. ; J R. Gowen, Esq. ; C. O, T. Of Foreign Works, M. Tonnelier; M. Blavier; J. C, Delame- therie; Hericart de Thury ; H. Lelivec; C. L. Cadet; M. Guyton- Morveau. And of British Memoirs abridged or extracted, William Her- shel, L.L.D. F.R.S.; T. A. Knight, Esq. F. R S. ; Mr. Wil- liam Brande; Everard Home, Esq. F. R. S. ; Humphry Davy, Esq. Sec. R, S. M. R. I. A. ; William Henry, M.D.'; Tho- mas Young, M.D. for. Sec. R. S. ; John Goldingham, Esq. F. R.S.; William Richardson, D. D.; W. Allen, Esq. F.R.S.; W. H. Pepys, Esq. F. R. S. ; Right Hon. Sir Joseph Banks, Bart. K. B. P. 1LS. ; Mr. James Parkinson; R. A. Salisbury, Esq. F.R. S.; Mr. John Dunbar; Henry Reeve, M.D. ; Dr. James Howison; Mr. James Broad; Bath Agricultural Society; Lord Somerville; John Billingsley, Esq. ; Mr. Charles le Caan ; James Edward Smith, M. D. F. R. S. P.L. S.; William Hunter, Esq. -Sec. A. S. ; Mr. William Anderson; Dr. Alexander Anderson. The Engravings consist of 1. An improved Goniometer, by the Rev. William Burrows: 2. Views of the late Comet, by Dr. Her- schel: 3. Crystals of the Diopside, a new Species of Mineral: 4. Mr. Christopher TowilPs Life Boat: 5. Delphinus Melas, a non descript of the Order Cere: 6. Dr. W. Henry's Apparatus for the Analysis of the Compound inflammable Gasses by slow Combustion: 7. Messrs. Alien and Pepys's Apparatus for showing the Changes produced in Air by Respiration. 8. View of Port- moon: 9. View of Pleskin, on the N. W. Side of Bengore Pro- montory: 10. Sir George Cay ley's Plan for a Theatre: 11. The Chinese Method of propagating Fruit Trees: 12. Mr. Broad's In- strument for measuring standing Timber: 13. Mr. Le Caan's im- proved Tram Plates for Rail Roads: 14. Guyton-Morveau's per- manent Apparatus for destroying Contagion. TABLE TABLE OF CONTENTS TO THIS TWENTY-SECOND VOLUME, JANUARY, J 309. Engravings of the following Objects: 1. An improved Goniometer, by the Rev. William Burrow j 2. Views of the late Comet, by Dr. Herschel: 3. Crystals of the Diopside, a new Species of Mineral s 4. Mr. Christopher TowilPs Life Boat. I. An Account of a Goniometer invented by the Rev. E. J. Burrow, A. M. FeU low of Magdalen College, Cambridge - - i II. Observations of a Comet, made with a View to investigate its Magnitude, and the Nature of its Illumination. By William Herschel, LL. D. F. R. S. 3 III. Remarks on the Diopside, a new Species in Mineralogy established by Mr. Haiiy, comprising two Varieties found in the Piedmontese Alps by Mr. Bon- voisin, and described in the Journal de Physique for May 1806, under the Names of Mussite and Alalite. By Mr. Tonnelier, Keeper of the Cabinet of Mineralogy to the Council of Mines 14 IV. Letter from Sir Thomas Clarges, Bart, of Sutton upon Derwent, to W. An- nesley, Esq., on the Subject of Life-boats - - 20 V. On the Origin and Office of the Alburnum of Trees. In a Letter from T. A. Knight, Esq., F. R.S. to Sir Joseph Banks, Bart. K. B. P. R. S. 27 VI. Letter on Polygonal Numbers, in reply to Mr. Gough. By P. Barlow, Esq. - - - - - 33 VII. A Letter on the Differences in the Structure of Calculi, which arise from their beiug formed in different Parts of the Urinary Passages ; and on the Ef- fects that are produced upon them, by the internal Use of solvent Medicines, from Mr. William Brande to Everard Home, Esq., F. R. S. - 35 VIII. Some Observations on Mr. Brande's Paper on Calculi. ByEverard Home, Esq., F.R.S. - - - - - 54 IX. Electro-Chemical Researches on the Decomposition of the Earths ; with Observations on the Metals obtained from the Alkaline Earths, and on the Amalgam procured from Ammonia. By Humphry Davy, Esq., Sec. R.S. M. R. I. A. (Concluded from Vol. XXI, p, 383) - - 54 X. On the supposed universal Distribution of Fossil Coal, in Reply to Mr. B. Cook, p. 292; and on the Nature and Situations of the extraneous Fossil (Belemnite) analysed by Mr. J. Acton, at p. 305, under the Denomination of a " Crystal" called a Thunder-pick. In a Letter from Mr, John Farey 68 XI- Account of a British Vegetable Product, that may be substituted for Coffee. Iq a Letter from Mr. William Skrimshire, Jun. - - , 70 XII. Account of some ferruginous Rocks serving as Substitutes for Emery, By Mr. Blavier, Mine Engineer - - - - 74 XIII. Onthe Anthophyllite. By J.C. Delametherie - * 76 Scientific News ---_-„ jD, MeteorologicalTable ■• 80 FEBRUARY, CONTENTS. v, FEBRUARY, 1809. Engravings of the following Objects: 1. Delphi mis Melasma nondescript Spe* cies of the Order Get* from an original Drawing: 2. Dr. W. Henry's Ap- paratus for the Analysis of the compound inflammable G asses by slow Conv bustion, I. Description of a new Species of Whale, Delphinus Melas. In a Letter from Thomas Stewart Traill, M. D. SI JI. Description of an Apparatus for the Analysis of the Compound Inflammable Gasses bv slow Combustion ; with Experiments on the Gas from Coal, ex- plaining its Application. By William Henry, M. D., Vice Pres. of the Lit* and Phil. Society, and Physician to the Infirmary at Manchester. Commu- nicated by H. Davy, Esq., Sec. It. S. - - - 83 III. Account of a new Irregularity latelv perceived in the apparent Figure of the Planet Saturn. By William*Herschel,-LL. D. F. R. S. - 100 IV. Hvdraulic Investigations, subservient to an intended Croonian Lecture on the Motion of the Blood. By Thomas Young, M. D. For. Sec. It. S. 104 V. A Mi nera logical Description of the Mountain and Silver Mine of Cha- lanches, in the Department of the Isere. By Hericart de Thury, Mine Engineer ' ' '. 'J - - - - 134 VI. Effects of Gravity on the Balance of a Watch compared with those on (he Pendulum of a Clock. In a Letter from a Correspondent - 13 * VII. An Account of a simple and economical Method of preparing an artificial Cheltenham Water highly impregnated with Carbonic Acid (fixed Air). By- Richard Greene, Esq. of Cork, A. B. Trin. Col. Dub., M. D., and Presi- dent of the Royal Medical Society, Edinburgh - - 139 \TII. Second Letter on the xVdvantages of Coal Gas Lights. By Mr. B. Cook 145 IX. On the Superiority of Platinafor making the Pendulum Spring of Watches, By Mr. James Scott" - - - - - 148 X. On the Construction of Galvanic Batteries. In a Letter from a Correspon- dent ------- 140. XI. Account of an economical Method of evaporating the Water of Brine- springs, employed at the Salt Works of Moutiers, in the Department of Mont-; Blanc. By Mr. II. Lelivec, Engineer of Mines, &c. for the Departments of Mont-Blanc and the Leman Lake - - - 151 XII. Eclipses of the Satellites of Jupiter, observed by John Goldingham, Esq. F. R. S., and under his Superintendance, at Madras, in the East Indies J 53 Scientific News - - - r 15tf Meteorological Journal - ? - - - 100 MARCH, *i CONTENTS. MARCH, 1809. Engravings of the following Objects: 1 . Messrs. Allca and Pepys*s Apparatus for showing the Changes produced in Air by Respiration: 2. View of Port- moon. I. A Letter on the Alterations that have taken place in the Structure of Rocks, on the Surface of the basaltic Country in the Counties of Derry and Antrim. Addressed to Humphry Davy, Esq. Sec. R. S. By Wm. Richardson, D. D. 1G1 f I. On the Purification of Camphor by Means of Potash. In a Letter from a Correspondent - - -* - - 170 III. An Account of some Peculiarities in the anatomical Structure of the Wombat By Everard Home, Esq. F. R. S. - - 177 IV. On the Changes produced in Atmospheric Air, and Oxigen Gas, by Re- spiration. By W. Allen, Esq. F. R. S., and W. H. Pepys, Esq. F. R. S. 180 V. A Letter on Comets, addressed to Mr. Bode, Astronomer Royal at Berlin. Received from the Author - 206 VI. An Example of the Utility of a Series in finding a Fluent. By a Corre- spondent ------ 21" VII. An Account of the Method of cultivating the American Cranberry, Vac- cinium Macrocarpum, at Spring Grove. By the Right Hon. Sir Joseph Banks, Bart. K. B. P. R. S. &c. - - - 21t> VIII. On the Existence of Animal Matter in Mineral Substances. From Par- kinson's Organic Remains - - - - 2 IS IX. Observations on the different Species of Dahlia, and the best Method of cultivating them in Great Britain. By R. A. Salisbury, Esq. F. R.S. 224 X. Some Questions in Ornithology. In a Letter from a Correspondent 233 XI. On the GoW Mines in the Department of the Isere. By Hericart de Thury, Mine Engineer ----- 934 Scientific News * 237 Meteorological Journal * 24* APRIL, CONTENTS. Tii APRIL, 1S(&. Engravings of the following Objects: 1. View of Pleskin on tke North West Side of Bengore Promontory: 2. Sir George Cay ley's Plan for a Theatre. E, Plan for an improved Theatre. By Sir George Cayley, Bart. In a Letter from the Author - - - - - 241 ! ] A Letter on the Alterations that have taken place in the Structure of Rocks, on the Surface of the Basaltic Country in the Cduntiea of Derry and Antrim. Addressed to Humphry Davy, Esq., Sec. R. S. by William Richardson, D. D. 245 III. Remarks on the Habits of the Tmber and Northern Divers, in answer to a Correspondent. In a Letter from Thomas Stewart Traill, M. D. 250 IV. Inquiry concerning the Use of Galvanism in Deafness. By a Correspon- dent ------ 260 V. An Addition Table, with a Multiplication Table on a new Plan. By Mr. Charles Hayter ----- 261 VI. On the Cultivation of the common flax, Linuui Usitatissimum of Linne, as an ornamental Plant in the Flower Garden. By Mr. John Dunbar, Gar- dener to Thomas Fairfax, Esq. - - - 264- VII. Analysis of a Mineral Water near Dudley, in Worcestershire. By Mr. H. W. Weldon - - - - 266 VIII. On the Gold Mines in the Department of the Isere. By Hericart de Thury, Mine Engineer - - - - 219 IX. A short Account of Nectarines and Peaches naturally produced on the same Branch. By R. A. Salisbury, Esq. F. R. S. &c. - - 284 X. On the Substitution of Iron for Mahogany and other expensive Kinds of Wood in Articles of Furniture and other Purposes. By Mr. B. Cook 287 XI. On ascertaining Square Numbers and Biquadrates by Inspection. By W. Saint, Esq. - - - - - 291 XII. Some Account of Cretinism. By Henry Reeve, M. D. of Norwich. Communicated by William Hyde Wolfaston, M. D. Sec. R. S. 294 XIII. On the Composition of -the Salts of Barytes. By Mr, Arthur Aikin 301 XIV. A Memoria Technica for double Elective Attractions. By Thomas Young, M. D. F. R. S. - - - - 304 XV. An Abstract of a Meteorological Journal for the Years 1807 and 1808, kept at Middleshaw, near Kendal, in Latitude 5i° 20'. By John Gough, Esq. ------ 305 XVI. An Essay on Electrical Attractions and Repulsions. By Mr. • • * 303 XVII. Analysis of the English Medicine called James's Powder. Communi- cated by Mr. C. L. Cadet, Apothecary - - . - 316 Scientific News - - - - - 3 1 8 Meteorological Table - - - - - 320 SUPPLEMENT viil CONTEN T S. SUPPLEMENT TO VOL. XXII. Engravings of the following Objects: 1. The Chinese Method of propagating Frtlit Trtes \ 2. Mr. Broad's Instrument for measuring standing Timber: 3; Mr. le Caan's improved Tram Plates for Rail Roads : 4. Guyton-Morveau's permanent Apparatus for destroying Contagion. I. An Account of the Chinese Method of propagating Fruit Trees by Abscis- sion. By Dr. James Ilowison .... 32t Jl. Description of a Gauge or Measure for standing Timber, invented by Mr. James Broad, of Downing Street - _ . 324r III. Report of a Committee appointed by the Bath and West of England So- ciety, to investigate the Claim of the Right Hon. Lord Somerville to a Pre- mium " for the greatest Number and most profitable Sort of Sheep." 321 IV. On the Advantages of the Use of Oxen and Neat Cattle in Husbandry. By Lord Somerville - - - - 330 ictical Statement on the foregoing Subject, with Claim of Premium. By John Billingsley, Esq. - - - 334 VI. On the Conversion of French Weights into English. In a Letter from Mr. JohnFarey - - - - 337 YII. Acrount of an Improvement in Tram-plates for Carriages on Rail Roads, By Mr. Charles le Caan, of Llanelly in \\ ales - - 339 VIII. Observations on the Use of Acid Fumigations in purifying the Air and stopping the Progress of Contagion, and the most simple Means of com- pletely obtaining this Effect. Extracted from the Correspondence of Mr. Guyton-Morveau - 344 IX. Account of a Well for preserving and filtering Rain-water for domestic Purposes, where a Supply of Spring-water was not easily to be obtained* Communicated by J. R. Gowen, Esq. - 353 X. An Inquiry into the Structure of Seeds, and especially into the true Nature of that rart called by G«rtner the Vitellus. By James Edward Smith, M. D. F.R.S. P.L.S. - - * - - 354 XI. Observations on Nauclea Gambir, the Plant producing the Drug called Gutta Gambeer, with Characters of two other Species. By William Hunter, Esq. Secretary to the Asiatic Society. Communicated by the President 36*6' XII. On the Varu-gation of Plants. In a Letter to Richard Anthony Salisbury, Esq, F. R. S. and L. S. by Thomas Andrew Knight, Esq, F. R. S. and L. S, 370 XIII. Method of Painting Linen Cloth with Oil Colours, so as to be more pli- ant, durable, and longer impervious to Water, than in the usual Mode. By Mr. William Anderson, of his Majesty's Dock-yard, Portsmouth 373 XIV. Account of the Royal Botanical Garden in the Island of St. Vincent. By Dr. Alexander Anderson - 380 XV. Query on Accidents frequently happening to Dies with which Medals are struck. In a Letter from a Correspondent. - - 383 Scientific News. - - - i - 38* Mcholsom FhOos. Journal* , Vol. ZM.FIJ. p.l. jL^J^JtiMtmy W7u. F.R.S*. JL HE comet, which we have lately observed, was pointed Comet when out to me by Mr. Piggot, who discovered it at Bath the 28th of September, and the first time I had an opportunity of examining*it was the 4th of October, when its brightness to the naked eye gave me great hopes to find it of a differ- ent construction from many I have seen before, in which no solid body could be discovered with any of my telescopes. Jn the following; observations, my attention has been di- Examined ,& / ,., i • with respect f rected to such phenomena only, as were likely to give us -lts physical some information relating to the physical condition of the condition, comet, it will therefore not be expected, that I should give an account of its motion, which I was well assured would be most accurately ascertained at the Royal Observatory at Greenwich. » The different parts of a comet have been generally ex- Terms relating pressed by terms that may be liable to misapprehension, qUentlymisap* such as the head, the tail, the coma, and the nucleus; for plied. in reading what some authors say of the head, when they speak of the size of the comet, it is evident that they take it for what is often called the nucleus. The truth is, that inferior telescopes, which cannot show the real nucleus, will give a certain magnitude of the comet, which may be called its head ; it includes all the very bright surrounding light ; nor is the name of the head badly applied, if we keep it to this meaning; and since, with proper restriction, the terms which have been used may be retained, I shall give a short account of my observations of the comet, as they re- late to the above-mentioned particulars, namely, the nucleus, the head, the coma, and the tail, without regarding the oi- lier of the time when they were made. The date of each * Philosophical Transactions for jSo$, Part II, p. 145. B % observation, OBSERVATIONS OF A COMET. Nucleus. Nucleus has a Visible dirk, "which is real. Apparently observation, however, will be added, that any person who may hereafter be in possession of more accurate elements of the comet's orbit, than those which 1 have at present, may repeat the calculations in order to obtain a more accurate rer suit. Of the Nucleus. From what has already been said, it will easily be tinder? stood, that, by the nucleus of the comet, I mean that part of the head which appears to be a condense3 or solid body, and in which none of the very bright coma is included. It should be remarked, that from this definition it follows, that when the nucleus is very small, no telescope, but what has light and power in an eminent degree, will show it distinctly. Observations. Oct. 4, 1807. 10-feet reflector. The comet has a nu- cleus, the disk of which is plainly to be seen. Oct. 6. I examined the disk of the comet with a proper set of diaphragms, such as described in a former paper*, in order to see whether any part of it were spurious ; but when the exterior light was excluded, so far from appearing larger, as would have been the case with a spurious disk, it appeared rather diminished for want of light; nor was its diameter lessened when I used only the outside rays of tiie mirror. The visible disk of the comet therefore is a real one. Oct. 4. I viewed the comet with different magnifying powers, but found that its light was not sufficiently intense to bear very high ones. As far as 200 and 300, my ]0 feet reflector acted very well, but with 400 and 500 there was no? thing gained, because the exertion of a power depending on the quantity of light was obstruetedf, which I found was here of greater consequence than the increase of magnitude. Illumination of the Nucleus. Oct. 4, Ch. 15/ The nucleus is apparently round, an4 * See Phil. Trans, for 1805, page 53. Use of the Criterion + See Phil. Trans, for 1800, p. j8. equally OBSERVATIONS OF A COMET. 5 equally bright all over its disk. I attended particularly to round and uni- its roundness. formly bright. Oct. 18* The nucleus is not only round, but also every- where of equal brightness. Oct. 19. I see the nucleus again, perfectly round, well defined, aud equally luminous. Its brilliant colour in my 10 feet telescope is a little tinged with red; but less so than that of Arcturus to the naked eye* Magnitude of the Nucleus. Oct. 2G. In order to see the nucleus as small as it really its magnitude* is, we should look at it a long while, that the eye may gra- dually lose the impression of the bright coma which sur- rounds it. This impression will diminish gradually, and when the eye has got the better of it, the nucleus will then be seen most distinctly, and of a determined magnitude, Oct. 4. With a 7 feet reflector I estimated the diameter Diameter less of the nucleus of the comet at first to be about five seconds, than 3 seconds. but soon after I called it four, and by looking at it longer, I supposed it could not exceed three seconds. Oct. 6. 10 feet reflector, power 221. The apparent disk Apparent disk of the comet is much less than that of the Georgian planet, Iess than tha* which being an object I have seen so often with the same in- strument, and magnifying power, this estimation from me- mory cannot be very erroneous. Oct. 5. Micrometers for measuring very small diameters,Compared with when high magnifying powers cannot be used, being very globules of little to be depended upon, I erected a set of sealing wax sea U'S wax' globules upon a post at 2422 inches from the object mirror of my 10 feet reflector, and viewed them with an eye glass, which gives the instrument a power of 221, this being the same which I had found last night to show the nucleus of the comet well. I kept them in their place all the day, and reviewed them from time to time, that their magnitudes might be more precisely remembered in the evening, when I intended to compare the appearance of the nucleus with them. On examining the comet, I found the diameter of its nu- cleus to be certainly less than the largest of my globules, which, being -04G6 of an inch, subtended an angle of 3"*97 at the distance of the telescope in the day time. Comparing O OBSERVATIONS OF A COMET. Comparing the nucleus also with the impressions, which the view of the second and third had left in my memory, and of which the real diameters were *0325 and '0290 of an inch : and magnitudes at the station of the mirror 2""77 and 2"*47> I found, that the comet was almost as large as the second, and a little larger than the third. Oct. 18. The nucleus is less than the globule which sub- teuds 2"-77. Oct. 19. The air being uncommonly clear, I saw the co- met 40 minutes after five, and being now at a considerable altitude, I examined it with 289, and having but very lately reviewed my globules, I judged its diameter to be not only less than my second globule, but also less than the third : that is, less than 2"*47. Oct. 6. The 20-feet reflector, notwithstanding its great light, does not show the nucleus of the comet larger than the 10 feet, with an equal magnifier, makes it. Oct. 28. My large. 10 feet telescope, with the mirror of 24 inches in diameter, does not increase the size of the nu- cleus. Compared Oct. 6. Being fully aware of the objections, that may be wUh theSdsa- made against the method of comparing the magnitude of tellitfcof Juui- 7 . • ,. , , ter. the nucleus ot the comet with objects that cannot be seen together, I had recourse to the satellites of Jupiter for a more decisive result, and with ray 7 feet telescope, power 202, I - viewed the disk of the third satellite and of the nucleus of the comet alternately. They were both already too low to be seen very distinctly ; the diameter of the nucleus however appeared to be less than twice that of the satellite. Oct. 18. With the 10 feet reflector, and the power 221, a similar estimation was made; but the light of the moon would not permit a fair comparison. Examined with Oct. 19. I had prepared a new 10 feet mirror, the delicate a new mirror. p0ijsn Gf my former one having suffered a little from being exposed to damp air in nocturnal observations. This new one being uncommonly distinct, and the air also remarkably clear, I turned the telescope from the comet to Jupiter's third satellite, aud saw its diameter very distinctly larger than the nucleus of the comet. I turned the telescope again to the comet, and as soon as I saw it distinctly round and well OBSERVATIONS OF A COMET. 7^ well defined, I was assured that its diameter was less than that of the satellite. 6h 20'. I repeated these alternate observations, and al- ways found the same result. The night is beautifully clear, and the moon has not yet risen to interfere with the light of the comet. Nov. 20. "With a 7 feet reflector, and power only 75, I can also see the nucleus; it is extremely small, being little more than a mere point. Of the Head of the Comet. When the comet is viewed with an inferior telescope, or if Head of the the magnifying power, with a pretty good one, is either much comet- too low, or much too high, the very bright rays immediately contiguous to the nucleus will seem to belong to it, and form what may be called the head. Oct. 19. I examined the head of the comet with an indif- ferent telescope, in the manner I have described, and found it apparently of the size of the planet Jupiter, when it is< viewed with the same telescope and magnifying power. With a good telescope, I saw in the centre of the head a very small well defined round point. Nov. 20. The head of the comet is now less brilliant than it has been. Of the Coma of the Comet, The coma is the nebulous appearance surrounding the Us coma, head. Oct. 19. By the field of view of my reflector, I estimate, the coma of the comet to be about 6 minutes in diameter. Dec. 6. The extent of the coma, with a mirror of 24 inches diameter, is now about 4' 45". Of the Tail of the Comet. Oct, 18. 7h. With a night glass, which has aiield of view Its tail, of nearly 5°, I estimated the length of the tail to be 3Q|; but twilight is still very strong, which may prevent my see- ing the whole of it. Nov. 20. The tail of the comet is still of a considerable length, certainly not less than 2§ degrees. Oct. 8 OBSERVATIONS OF A COMET. Oct. 26. The tail of the comet is considerably longer on the south-preceding, than on the north-following side. It is not bifid, as I have seen the comet of 1769 delineated by a gentleman who had carefully observed it*. Oct. 28. 7 feet reflector. The south-preceding side of the tail in all its length, except towards the end, is very well de- fined ; but the north-following side is every where hazy and irregular, especially towards the end ; it is also shorter than the south-preceding one. The shape of the unequal length of the sides of the tail, when attentively viewed, is visible in a night glass, and even to the naked eye. Oct, 31. 10 feet reflector. The tail continues to be better defined on the south-preceding than on the north-following side. Dec. 6. The length of the tail is now reduced to about 23' of a degree. Of the Density of the Coma and Tail of the Comeh Density of the Many authors have said, that the tails of comets are of so cotna and tail rare a texture, as not to affect the light of the smallest stars that are seen through them. Unwilling to take any thing upon trust, that may he brought to the test of observation, I took notice of many small stars, that were occasionally covered by the coma and the tail, and the result is as fol- lows. ffi-% ^ct* 2^» ^* *5, Large 10 feet reflector, 24 inches aper- obscure the ture. A small star within the coma is equally faint with two tiarS ilTtl other stars that are on the north-following side of the comet, but without the coma. 7h. 30'. The coma being partly removed from the star, it is now brighter than it was before. Oct. 31, 6h. 5'. 10 feet reflector: A star in the tail of the comet, which we will call a, is much less bright than two others, b and c, without the tail. Two other stars, d and e, towards the south of b and e> are in the following skirts of the tail, and are extremely faint. 7h. 20'. The star e is now considerably bright, the tail * Dr. Lind of Windsor. having OBSERVATIONS OF A COMET. £ having left it, while d, which is rather more involved than it was before, is hardly to be seen. 7I1. 50'. The star a, toward which the comet moves, is- involved in denser nebulosity than before, and is grown fainter* d is involved in brighter nebulosity than before, but being near the margin, it will soon emerge. 8b. 35'. Being still more involved, the star a is now hardly visible. e is quite clear of the tail, and is a considerable star; d re- mains involved. 9b. 10'. The star d is also emerged, but the cornet is now too low to estimate the brightness of stars properly. Nov. 25, 7h. 35'. There is a star a within the light of the tail, near the head of the comet, equal to a star b situate without the tail, but near enough to be seen in the field of view with a. The path of the head of the comet leads towards a, and a more intense brightness will come upon it. 8h. 46'. The starn is now involved in the brightness near the head of the comet, and is no longer visible, except now and then very faintly, by occasional imperfect glimpses; but the star b retains its former light. Nebulous appearance of the Comet. Dec. 6. The head of the comet, viewed with a mirror of Nebulous ap- 24 inches diameter, resembles now one of those nebulae, P ea rauce o£the which in my catalogues would have been described, " a very * large, brilliant, round nebula, suddenly jnuch brighter in the middle/' Dec. 16. 7 feet reflector. The night being fine, and the moon not risen, the comet resembles " a verv bright, larce, irregular, round nebula, very gradually much brighter in the middle, with a faint nebulosity on the south-preceding aide." Jan. 1, 1808. 7 feet. " Very bright, very large, very gra- dually much brighter in the middle." . If 1 had not known this to be a comet, I should have ad- ded to my description of it as a nebula, that the centre of it might consist of very small stars; but this being impossible, 1 directed my 10 feet telescope with a high power to the co- met 10 OBSERVATIONS OF A COMET. met, in order to ascertain the cause of this appearance; in consequence of which I perceived several small stars shining through the nebulosity of the coma. Jan. 14. 7 feet. " Bright, pretty large, irregular round, brighter in the middle.'* Feb. 2. 10 feet, 24 inch aperture. " Very bright, large, irregular round, very gradually much brighter in the mid- dle." There is a very faint diffused nebulosity on the north preceding side; I take it to be the vanishing remains of the comet's tail. Feb. lj). Considerably bright; about \ of the field — 3' 26 " " in diameter, gradually brighter in the middle.'' The faint nebulosity in the place where the tail used to be still projects a little farther from the centre than in other directions. Feb. 21. Less bright than on the 19th; nearly of the same size*, gradually brighter in the middle. The nebulosity still a little projecting on the side where the tail used to be. Result of the foregoing Observations. General infer- From the observations which are now before us, we may ences. draw some inferences, which will be of considerable import- ance with regard to the information they give us, not only of the size of the comet, but also of the nature of its illumina- tion. It is a solid A visible, round, and well defined disk, shining in every bo<1.v» part of it with equal brightness, elucidates two material cir- cumstances; for since the nucleus of this comet, like the body of a planet, appeared in the shape of a disk, which was experimentally found to be a real one, we have good reason to believe, that it consists of some condensed or solid body, the magnitude of which may be ascertained by calculation. For instance, we have seen, that its apparent diameter, the 19th of October, 6h. 20', was not quite so large as that of the third satellite of Jupiter. In order therefore to have some idea of the real magnitude of our comet, we may ad- mit, that its diameter at the time of observation was about l", which certainly cannot be far from truth. The diameter of the 3d satellite of Jupiter, however, is known to have a permanent disk, such as may at any convenient time be measured OBSERVATIONS OF A COMET. 11 measured with all the accuracy that can be used ; and when the result of such a measure has given us the diameter of this satellite, it may by calculation be brought to the dis- tance from the Earth at which, in my observation, it was compared with the diameter of the comet, and thus more accuracy, if it should be required, may be obtained. The following result of my calculation however appears to me quite sufficient for the purpose of general information. From the perihelion distance 0*G474<>1, and the rest of the given elements of the comet, we find, that its distance from the as- cending node on its orbit at the time of observation was 73° 45' 44"; and having also the Earth's distance from the same node, and the inclination of the comet's orbit, we com- pute by these data the angle at the sun. Then by calculat- ing in the next place the radius vector of the comet, and having likewise the distance of the Earth from the sun, we find by computation, that the distance of the comet from the Earth at the time of observation was 1*169192, the mean dis- tance of the Earth being 1. Now since the disk of the comet was observed to subtend an angle of l", which brought to the mean distance of the Earth gives l<*l69, and since we also know that the Earth's diameter, which, according to Mr. Dalby, is 79-13,c2 miles*, subtends at the 538 miles m same distance an angle of I7""2 we deduce from these ia e r* principles the real diameter of the comet, which is 538 miles. Having thus investigated the magnitude of our comet, we Its illumina- may in the next place also apply calculation to its iliumina- tion* tion. The observations relating to the light of the comet were made from the 4th of October to the 19th. In all which time the comet uniformly preserved the appearance of a planetary disk fully enlightened by the sun: it was every where equally bright, round, and well denned on its borders. Now as that part of the disk which was then visi- ble to us could not possibly have a full illumination from the sun, 1 have calculated the phases of the comet for the • See Phil. Trans, for 1791, page 239. Mr. Dalby gives the two se. miaxes of the Earth, from a mean of which the above diameter 7913-1682 |S obtained. 4th l£ OBSERVATIONS OF A COJIET. 4th and for the 19th, the result of Which is, that On the 4tf> the illumination was 119° 45' 9", as represented in PI. I, fig. 3, and that on the 19th it had gradually increased to 124° 22' 40", of which a representation is given in tig. A* Both phases appear to me sufficiently defalcated, to prove that the comef did not shine by light reflected from the sun only ; for had this been the case, the deficiency I think would have been perceived, notwithstanding the smallness of the object. Those who are acquainted with my experi- ments on small silver globules* wi'l easily admit, that the same telescope, which could show the spherical form of balls, that subtended only a few tenths of a second in dia- meter, would surely not have represented a cometary disk as circular, if it had been as deficient as are the figures which give the calculated appearances. indicates it to jf these remarks are well founded, we are authorised to be luminous of 1,11,10, • „ . ,„ iuelf. conclude, that the body ot the comet on its surface is selr- luminous, from whatever cause this quality may be derived. The vivac'ity of the light of the comet also had a much greater resemblance to the radiance of the stars, than to the mild reflection of the sun's beams from the moon, which is an additional support of our former inference. Which is far- The changes in the brightness of the small stars, when ther proved by ^e are succes&ivelv immerged in the tail or coma of the the stars seen J J ° • i , 1 , through the comet, or cleared from them, prove evidently, that they are tai!- sufficiently dense to obstruct the free passage of star-light. Indeed if the tail or coma were composed of particles that reflect the light of the sun, to make them visible we ought rather to expe< ,, that the number of solid reflecting parti- cles, required for this purpose, would entirely prevent our seeing any stars through them. But the brightness of the head, coma, and tail alone, will sufficiently account for the observed changes, if we admit, that they shine not by reflec- tion, but by their own radiance ; for a faint object projected on a bright ground, or seen through it, will certainly appear somewhat fainter, although its rays should meet with no ob- struction in coining to the eye. N<;w, as in this case we are sure of the bright interposition of the parts of the comet, * See Phil. Traus. for 1805, p. 38, the 5th experiment. but OBSERVATIONS OF A COMET. J 3 but have no knowledge of floating particles, we ought cer* tainly not to ascribe an effect to a hypothetical cause, when the existence of one, quite sufficient to explain the pheno- mena, is evident. If we admit, that the observed full illumination of the disk Other circurn- of the comet cannot be accounted for from 'reflection, we the same. may draw the same conclusion, with respect to the bright- ness of the head, coma, and tail, from the following consi- deration. The observation of the 2d of February mentions, that not only the head and coma were still very bright, but that also the faint remains of the tail were still visible; but the distance of the comet from, the Earth, at the time of observation, was nearly 240 millions of miles*, which proves, I think, that no light reflected from floating particles could possibly have reached the eye, without supposing the number, extent, and density of these particles far greater than what can be admitted. My last observation of the comet, on the 21st of Feb- ruary, gives additional support to what has been said ; for at the time of this observation, the comet was almost 2*9 times the mean distance of the sun from the Earthf . It was also nearly 2*7 from, the sun J. What chance then could rays going to the comet from the sun, at such a distance, have to be seen after reflection, by an eye placed at more than 275 millions of miles § from the comet? And yet the instant the comet made its appearance in the telescope, it struck the eye as a very conspicuous object. The immense tails also of some comets that have been ob- Tails of comets served, and even that of the present one, the tail of which, not vapour, on the 18th of October, was expanded over a space of more than 9 millions of miles||, may be accounted for more satis- factorily, by admitting them to consist of radiant matter, guch as, for instance, the aurora borealis, than when we un- necessarily ascribe their light to a reflection of the sun's il- * 839894939* •J* The suns mean distance being i, that of the comet was a 89797. % The comet's distance from the sun was z-6$3T96, § 275077889, 11 9i6°5i*- . lumination tf ON THE DIOPSIDE. Rumination thrown upon vapours supposed to arise from the J>ody of the comet. By the gradual increase of the distance of our comet, we have seen, that it assumed the resemblance of a nebula ; and it is certain, that had I met with it in one of my swee]>s of the zones of the heavens, as "it appeared on either of the days between the 6th of December, and the 21st of February, it would have been put down in the list 1 have given of nebulae. This remark cannot but raise a suspicion, that some comets may h::.ve actually been seen under a ne- bulous form, and as such have been recorded in my cata- logues; and were it not a task of many years labour, I should undertake a review of all my nebulce, in order to see whether any of them were wanting, or had changed their place, which certainly would be an investigation, that might lead to very interesting conclusions. III. Remarks on the Diopsidc, a new Species in Mineralogy esta- blished by Mr. Haiiy, comprising two Varieties found in the Piedmontese Alps by Mr. Bonvoisin, and described in the Journal de Physique for May, 1806, under the names of Mussite and Alalite. By Mr. Tonnelier, Keeper of the Cabinet of Mineralogy to the Council of Mines*. Di-covery of Jl HE naturalist, who is led by his zeal to researches ajt- "ew.s,,bstant; tended with much toil, feels himself well rewarded, if in ths best reward ' of the natu- his travels he be so fortunate, as to meet with substances not rahst. ye|. jinown> Such discoveries he considers as the most valu- able recompense of his labours; and he deems it his duty, to publish descriptions of the new objects, with which he has enriched the field of science. Mr. Bonvoisin, a much respected natural philosopher, member of the imperial aca- demy of Turin and of the legislative body, has recently ex- This occurred perjenced this satisfaction. Many celebrated naturalists had toBonvoi-sm in ....... . , • the Piedmon- visited the Piedmontese Alps before him, and made known tese_Alp$. ^0 us, among the subjects they have had opportunities of ob- • Journal des Mines, vol. XX, p. 65. serving, OK THE DIOPSIPE. 15 serving, those that appeared to them most interesting either for their novelty or their rarity. The-lithology of these re- gions, less assiduously cultivated than the other branches of natural history, appeared to the learned academician an am- ple field, in which science might promise itself a rich har- vest. His expectations were not disappointed, and the re- sult of his researches, the merit of which is enhanced by the difficulties he had to overcome, is an account of his tra- vels, the speedy appearance of which he gives us reason tq> hope. In the mean time we have to express our thanks to Mr. Bonvoisin for having made us acquainted with the prin- cipal substances he has collected in his mineralogical tour. Of these a very ample description is given in the Journal de Physique for May 1806, but my attention is confined at pre- sent to two of them, to which he has given the provisional names of mussite and alalite. A few days ago I was present at a meeting, at which Mr. ywo 0f the Haiiy exhibited to several of his pupils the new substances, new substances ,. , , i -i • i • r» i i_« foundbvhim which he purposes to describe in his course ot lectures this particularly year, and among others those which Mr. Bonvoisin has sent noticed, from Piedmont to Mr. Fourcroy, who has destined the -most remarkable for the gallery of the Museum of Natural History*. Among these substances two particularly enga- ged my attention, which the celebrated professor of miner- alogy, informed us he had been led by his observations to urtite in one species, the essential characters of which differ completely from those that distinguish all the known spe- cies, notwithstanding their appearance seems to indicate, that they should be separated. The constant occupation, which the approaching publication of the second edition of his Treatise on Natural Philosophy imposes on Mr. Haiiy, not allowing him to publish the results of his examination of the substances in qxiestionf , I requested his permission, to take * Mr. Haiiy has since given a description of the diop=ide, which con- stitutes the subject of the present paper, in the public lecture on miner- alogy, which he gave at rhe Museum of Natural History on the jath of July this year. •f With respect to the diopside Mr. Haiiy has followed his usual cus- tom of committing to writing the new observations he delivers to his pu- pils, and depositing a copy in the library of the Museum, which every Diie is at liberty to transcribe after the lecture. this 16 Characters of the new spe- cies diopside. Determinate »anetics of form, primiiive. pidodecaedral ON THE DIOPSIDE. this task upon myself, and drew up an article on the subject for the Journal des Mines, persuaded, that these new obser- vations could not fail to be interesting to its readers. This I now purpose to perform, tracing here the principal charac- ters of the two substances discovered by Mr. Bonvoisin. Characters of the diopside. Its specific gravity is 3'2374. It does not scratch glass, or very slightly ; but scratches fluate of lime. Before the blowr pipe it fuses into a glass of the same greenish colour as the mass itself. Jta primitive form is a right angled quadrangu- lar prism, PI. I, hg. 5, with oblique bases, the angle of inci- dence between the diagonal drawn from A to O and the edge H is 107° 8'. The prism is subdVisible by very clean sec- tions in the direction of the diagonals of its bases}:. The divisions parallel to the bases are in general very clean; those that answer to the sides m m are less easy to obtain. I. Determinate varieties of form. The two principal varieties pointed out by Mr. Haiiy are, lot variety, Primitive diopside: a variety of the mussite of Mr. Bonvbisin. Fig. 5. Care must be taken, not to confound the joints exposed on breaking the crystals exhibiting this variety with its na- tural bases. 2d variety, Didodecaedral diopside, fig. 6. A twelve-sided prism, terminated at each extremity by six faces, situate two and two, one above the other. The angle of incidence between M and Mh 90* r and M 135° s and M p and r n and r I and s I and p t and s x and r I and M I and rhe sur. face contiguous to S, behind the crystal, 117° 55' This % If from the point O a perpendicular be let fall on the side opposite to the edge H, the ratio between this perpendicular and the part inter- cepted 135* 107° 8' J 37° 12' 145° 53' 124° 7' 161° 16' 153° 26' 1348 86' ON THE DIOPSIDE. ]7 Tins fignre is analogous to that described in the Journal The angles of i ™ . -i. *■ ** ii' i i a crystal must de Physique, May J806, p. 430, as belonging to the regular be accurateiy crystals of alalite. The author of the description was aware, ascertained, that, to give an accurate idea of a crystal, the number and position of the faces will not be sufficient, but that the quan- tities of the angles they form with each other must be as- signed; so that if he had contented himself with mentioning the number of sides that form the prism; and the faces that terminate it, he would have given but a very imperfect idea of the crystalline form he wished to make known, as the de- scription would apply to several different figures, on which account it would be of little use. However, having had re- ,. , . /. i • i which cannot course to the goniometer alone, the measures of which arebe done by merely approximations, without the assistance of calcula- measurement tion, he has not sufficiently guarded against the danger of giving angles inconsistent with the principles of geometry, to which the crystallographer exposes himself, who neglects the resources of algebra. Thus the faces M M being ac- knowledged to form a right angle with each other, and the angles of incidence between / M, and / s, or the edge that sometimes occupies'the place of the latter, being given, the third, or inclination of the face adjacent to s, follows neces- sarily. Now on calculating this from the other data in the • Journal de Physique, we find, that the result of the mecha- nical measurement is erroneous by several degrees. The descriptions of Rom e-de-F Isle, though in general Rom 4 de risle accurate, sometimes exhibit instances of these contradic- some,,ime^ , ii /» l i /» t mistaken from tions between the values ot the angles of the same crystal, trusting to the This learned gentleman, for instance, after having given 105° g°niometer» as the great angle of the rhombus of inverted carbonate of lime, which he called muriatic calcareous spar, gives 115° for the great angle of the principle section, or that which passes through the oblique diagonals of two opposite faces, and the intermediate edges*. Now if we take the first angle as given, we shall be led by calculation to IQQ°4 for the se- cond, which, makes a difference of more than 5° degrees cepted by it toward the point A will be V'ai : v'T; and this inter, cepted part will be to either of the edges, G or H, as I to 5. * Ctistallographie, vol, I, p. 520. Vol. XXII.— Jan. 1808. C ^ from 18 ON THE DIOPSIDE. from the angle determined by observation. This value is too tar from the truth, not to lead us to a suspicion of some irregularities in the crystal, which that celebrated crystallo- Geometrical grapher examined. It is equally certain, that calculation calculation would have acquainted him with his mistake, in affording cessary him a sure method of correcting his observation. I might, mention other instances, if T were not afraid of wandering from my subject. That which I have adduced is sufficient, to show the justice of the remarks on the manner of describ- ing crystals may by Mr. Hatiy in the Annals of the Museum assisted by the 0f Natural History. This gentleman has there shown, that ligation. " tne descriptions of a crystal, to be precise, must indicate the angles as determined by the concurrence of common geo- metry with that founded on the structure of minerals. By following this method, the only one compatible with strict accuracy, we shall be certain, that the angles will always agree with each other. They will be as so many limits, to* which the observer may come sufficiently near with the goni- ometer, to be able to refer a crystal to the species or variety, the characters of which it bears. This is all we can expect from this instrument, however nicely it may be executed, and however skilful the hand that employs it. The diopside To return to the diopside. Though this substance has a distinct spe- never vet been subjected to analysis, Mr. Hatiy does not he- sitate to consider it as a species, that should occupy a dis- tinct place in the system*. The few characters I have given are sufficient, to demonstrate this assertion, because they occupy the first rank among those that are truly specific. The primitive form obtained by mechanical division differs from all other known forms. Far from having the character of a limitation, it is remarkable for a singularity, that no other species has yet presented. This consists in the double appearance it exhibits, one in its prism, which is a foursided The diopside • The place assigned to the diopside is immediately aft«r the pyrox- ilf-!.,5?!^*1?!^ ene, the primitive form of which bears some analogy to it. In each the primitive form is a quadrangular prism : but Mr. Haiiy has ascertained, that this prism is rectangular in the diopside, while the faces of that of the pyroxene are inclined to each other in angles of about 92° and 88°. Be- sides, the primitive form of the diopside is subdivisible in the direction of the two diagonals of its bases, while that of the pyroxene is capable of fceing subdivided enly parallel to the greater diagonal. rectangle^ logy to thepy xoxeue ON THE DIOPSIDE. \() rectangle, the other in its bases, which are rhombs inclined to the sides of the prism. From this circumstance Mr. Haii^ lias suggested the name of diopside (double face.) II. Indeterminate varieties of form. Indeterminate varieties. S. Compressed and laminiform diopside*. While Mr. Compressed Sc Haiiy was examining the crystalline forms of the new spe- lammiform • c^ies, Mr. Tondi, a mineralogist of distinguished merit be- longing to the Museum of Natural History, looking over the collection Mr. Bonvoisin had sent, which was accompa- nied by a systematic catalogue, observed the flattened va- riety among some specimens of a different species. This variety, which belongs to the mussite, afforded Mr. Haiiy the mechanical division, by which the species is character- ized. 4. Cylindroid diopside: in prisms full of grooves or striae. Cylindroid. 5. Compact diopside. If we examine attentively the compact. crystals of mussite, we see them prolonged in an uninter- rupted series into a compact mass, which serves as their gangue, is of the same colour, though often not so dark, and cannot fail to be perceived to be the same substance, though in a less perfect state of crystallization, as Mr. Bon- voisiii conjectured. The colours of the diopside are green, greenish gray, Colours. greenish white, and yellowish white. It is sometimes trans- lucid, sometimes opake. The crystals of mussite are small, elongated, and com- Ctajs monly opake. Several are twisted, and exhibit the primitive form very undecidedly. The crystals of alalite are in gene- ral larger, translucid, and of a greenish white. The mussite has been found in the commune of la Balme- \fu<;S;te wher« de-Mussa, in the department of the Po, toward the north of found. the valley of Lans, in the interstices of a vein one or two yards thick, that traverses, at the height of four or five yards, a rock called the Black Rock, which is twelve or fifteen yards high. The crystals have sometimes a translucid gra- nular carbonate of lime for their gangue. * This variety of form answers to what Werner calls strahliger, radi- ated. C 2 The 20 ON LIFE BOATS. Alalite where The alalite has been discovered in a vein in the mountain of Ciarmetta, situate beyond that of Testa-Ciarva, at the Alp of la Mussa, near the village of Ala. It is commonly accompanied with green or pale yellow primitive garnets, and emarginated garnets of a hyacinth red, which have no- thing in common with the topaz. It was these last that Mr. Bonvoisin designated by the name of topazolites, because he thought them of a pleasing colour, which he compared with the yellow of the topaz. The pyrophy- J snan avaii myself of this opportunity to announce, that ' Mr. Haiiy has found the substance called pyrophysalite by Messrs. Hisinger and Berzelius, an analysis of which was given by these gentlemen in the Annales^de Chimie for May, 1806*, to be a variety of the aluminous fluate of silex (topaz), of a greenish white colour, and nearly opake. IV. Letter from Sir Thomas Clarges, Bart, of Sutton upon Derwent, toW. Annesley, Esq,, on the Subject of Life boats. Dear Sir, Portsmouth, Nov. 29, 1808. Lukin's patent A Promised to give you an account of Life-boats. In the boat. first plaCe there is one by Lukin, late a coach-maker in Long- A ere, who has published a treatise on it. It is a row- boat, and on the sides has something similar to mine, a hol- low case made air-tight, running the whole length of the Buoyed up by boat. A bird must have wings on each side to support it in cork, and air- the air; and thus we technically give the name of wings to ig eaaes. those parts on the sides of a boat, that tend to give it buoy- ancy. On the outside of the airtight cases in Lukin's boat is a layer or belt of cork : so that his wings are formed of airtight cases, to buoy up the boat in the water like blad- Balanced by ders, and of cork. To prevent the boat from upsetting, it is an iron keel. furmshed with a cast iron keel. Objections to The objections to Mr. Lukin's boat are these. The air- tight cases are not in compartments, or chambers, like mine ; and therefore, if forced through by a rock, or striking againft it * See our Journal, vol. XIX, p. 33. any ON IIFE BOAT9. 21 any projecting part of the wreck, the whole length would fill with water. Besides, they do not open at top like mine, nor, if they did, are they large enough to afford cabin room. Cork, if used in sufficient quantity to be serviceable, occu- pies considerable space, and likewise affords no room. The iron keel, though safe for sailing, is a very great incum- brance in rowing, particularly against a high wind and heavy sea, so that the boat could not move very fast. My boat, being large and wide, could never be upset, unless the men did it purposely; yet would answer briskly and steadily to the oars. I now come to the Shields boat, improperly called Great- Shields, or head's. This is sharp at both ends, like the funny-boats 50^tatheads about Westminster bridge, to row with either end foremost. The wings are of cork, of which there are two layers, or belts, on each side, one without the gunwale, the other within. The history of the Shield's boat in brief is this. Some gentlemen of Shields, seeing the frequent occurrence of the dreadful accident of shipwreck, offered a premium of two guineas to the person, who should produce the best mo- del of a life^boat ; and a committee was appointed, to exa- mine and decide on the models. A painter of Newcastle, of the name of Wouldhave, made Wouldhave's a model of copper, sharp and high at both ends, and belted inTenti<>n« with cork. This, being tried in a tub of water, would not sink when full ; and when upset, it righted again. Mr. Greathead, a shipbuilder of Shields, gave in a model Greathead's, of a boat he had seen in America, in shape much resembling a butcher's tray. This had a singular property for a life boat , it soon upset, and they could not get it back again, but it whold keep its bottom uppermost. The committee however rejected Wouldhave's, because copper would not swim ; and gave the prize to Greathead, because his model was made of wood. Two gentlemen of the committee went into a brickmaker's, moulded a model in clay, nearly the same shape as Wouldhave's, and floated with cork like his, and gave orders to Greathead to build a boat from this model. Greathead suggested a curved keel jnstead of a straight one, which was adopted. Thus his claim 22 ON LIFE BOATS. claim to invention was building boats of wood, and making? them like rocking boats. Objections to ^ne objections to this boat are glaring. The rowing this boat. against a heavy sea and wind with such elevated ends is like rowing against the wind with sails set. The idea of the gen- tlemen was to keep out the water. But what signified the water coining in, if the boat would not sink? Besides, a boat thus formed would be filled amidships by the first wave, in spite of the high ends. Then as the oars lie on a curved gunwale, the poor rowers at each end will be scarcely able to dip their blades in the water; while those in thec middle will be constantly catching crabs, as the sailors call it, and getting severe blows on the stomach. The curved keel too has the great inconvenience of making the boat rest as it were on a point, so as to be liable every moment to be turned round, and laid athwart the waves: and if she be not turned round, when a heavy wave strikes against her high bow, from being sharp at both ends she will run back- ward much faster than the rowers can pull her forward. Now mine is intended only to row forward, and her broad stern hinders her from being driven backward. There is one advantage however in rowing either end foremost; as the boat is liable from her curved keel to be spun round every minute, the men need not concern themselves about getting her round again, but may row on stern foremost, as if no- thing had happened. In fact the Shields boat is a farce to a real seaman, and never attempts any thing but moderate seas*. It is indeed much worse constructed for the purpose than any common row-boat, in all respects except the addi- tion of cork ; and this even Wouldhave did not invent in the eye of the law, since Lukin had a patent for it years before. Wouldhave's idea of high ends, to make the boat right her- self again, if she upset, though not so bad as that of keep- ing the water out, is like the proverb of penny-wise and pound-foolish : for you cannot well upset a large wide boat in rowing, and such ends may defeat the chief object, that pf being able to put out to a wreck against a tremendous jvind and sea, which is often to be expected. Another fault * See our Journal, vol. XXI, p. 132 : and for a description of a life boaf by Mr. Wilson, p. 124. Pf ON LIFE BOATS. 25 •f a curved keel is the difficulty it occasions of steering the boat straight, particularly when from the height of the end the steersman is so high above the water. To come to rny boat, of which a plan is given in plate 2. Description of You will perceive from her size and width, that she is secure ew oa * from upsetting, without being incumbered below with an iron keel, or above with high ends. She cannot sink, which is the chief thing. Her wings are close; and yet they can be opened to admit many things. The space of the boat is not occupied by belts of cork, or hollow cases that cannot open, like Lukin's: while the wings, from their size, afford cabin room ; and, being in compartments, if a rock force through one, the others remaiiiing sound will prevent the water from rising much in that which is damaged. Perhaps Mr. Lu- kin would say, if these be opened, and any thing put in them, they will cease to be wings, and will not buoy up the boat like a hollow case: but you know one great secret of buoyancy is the resistance at bottom. Thus put an empty basin into water, and try to sink it, and you will find how great its resistance is, though completely open at top: or by putting weights into it you may satisfy yourself, that it will float a considerable burden. In mine the burden can be suited to the occasion ; and if not wanted to hold any thing, keep the lids close, and they are airtight buoys. As the wings of my boat are so broad, they form a deck, on which people may lie, particularly if a few iron stanchions be placed along the gunwale and connected by ropes. These stanchions might have a joint at the bottom, allowing them to yield inwardly, but not outwardly, which would prevent any damage if a heavy sea should roll the boat against the wreck. You must remember a peculiar feature in the boat, the Herfecullari- larse cabin in the bow for women and children, with ven- tl?\' ° i i • • i • A lar6e cabin, tilators on the valve principle, to admit air upwards, but no water downwards. I need not dwell on the importance of this cabin, in cases of shipwreck, to affrighted and half drowned women and children. It is obviously an indispen- sable requisite to a life-boat, that it should be incapable of sinking; but mine cannot even fill, or be waterrlogged. and after ports This is effected by very simple means, which do not appear *? discharSe even 24 ON LIFE BOATS. Her gqod pro- perties. Lines floated by cork. Peculiar rud- der. Copper cases not essential. Useful tQ ships on discovery, or any large $hjus. even to have been thought of before. It must be observed, that the little space in the midships, where the rowers sit, is the only part in which the water, that breaks in, can lodge, But as the bottom of this space is above the level of the wa- ter without, there are two portholes at the stern, opening outr wardly like valves, at which the water will discharge itself; and when they fall too, the heaviest sea striking the stern, instead of finding its way in, will only serve to close them. Having stated the leading features of my boat, namely, that she will not upset, or sink, or be waterlogged ; that she affords cabin room ; that she is like a man of war's launch, well built for rowing, the oars not on a curve, but nearly in a right line, and low to the water, of which she draws little, a circumstance that renders her a fine pilot boat; I need not dwell on a few secondary points, which however it would be improper not to mention. These are her being provided with small ropes, or lines, fastened to hooks on the gunwale, and each having a piece of cork painted red at the exr tremity ; intended not only for persons who fall overboard, or swim from a wreck, to see and catch hold of; but to tow any for whom there may not be room in the boat : and her having a very powerful rudder, which reaches some inches below the keel, but will haul up level with it, when going in very shallow water, and then let down again. The copper, cases, though affording additional security to those who choose to be at the expense, are no mpre a necessary point of my plan, than coppering her bottom. The woodwork alone, if well executed and properly attended to, may be kept quite airtight. Tf the assistance of cork were to be called in, it appears to me, that it might be better applied than in the other boats, by filling the cases with cork jackets, to take to a crowded wreck ; in going off to which the cases would not be wanted for any other purpose, and the jackets would not be an encumbrance. You must be aware of the impor- tance of the side cabins, or cases, for stowing valuable goods from a richly laden vessel. A boat of this kind, but somewhat smaller dimensions, would be exceedingly useful to ships on voyages of disco- very, and indeed to any largt vessels; as it would not only frnswer for wooding and watering, but is peculiarly adapted ON LIFE BOATS, 25 for excursions up rivers, or small inlets of the sea, or explore ing clusters of islands. As a pleasure boat she answers extremely well. And with Excellent respect to her safety I can say, that I have sailed in her from Plea*ure boat- Brighton round the Cornish coast to Conway in North Wales, without any accident, though we experienced some very dreadful weather on the voyage. The following is a description of the boat, as built by Mr. Description of Christopher Towill, of Teignmouth, see Plate 2. this boat' Her length is 30 feet, her breadth 10, her depth 3 feet 6 inches. The space between her timbers is fitted up with pine wood; this is done with a view to prevent the water Jodging there. The pine wpod is well caulked and paid. She is buoyed up by 8 metal cases, 4 on each side ; these are watertight, and independent of each other. They will serve to buoy up six tons; but I find that all the buoyant parts of the boat, taken collectively, will buoy up ten tons. The cases are securely decked over, and boarded at the sides with pine. There is a scuttle to each ase to put gopds in ; the edges are lined with baize; and over each scuttle, m the case, is one of wood, of a larger s ze, the margin of which is lined in the same manner to exclude the water. Between the cases are Norwegian balks, bolted to the bottom, fastened to each other by iron clamps, and decked over. The depth of her keel is about 9 inches below the garboard-streak, the dead rising is 4 inches. Her keel is narrow at the under part, and wide above, for the purpose of giving the timber a good bed, which will support the bolts, in case a necessity should arise to encounter sandbanks. In sailing over a bar, or in places where the water is shal- low, the rudd.er will, with ease, draw up even with the keel, and when in deep water, it will let down, instantly, and with equal facility, a foot below it ; in consequence of which ad- vantage, the boat is found to steer remarkably well. The forecastle of the boat forms a cabin 10 feet wide, fj feet long, and 4 feet deep, into which women, children, and disabled persons may be put. It is amply supplied with air, by means of two copper ventilators. It is furnished be- sides with two grapnels, very proper to be thrown on board a wreck, to ride by. The grapnel ropes will assist the suf- ferers 25 ' ON LIFE BOATS. ferers to remove, and escape from the wreck to the boat. She is likewise equipped with masts and sails, and is as manageable with them as any boat of her dimensions can pos- sibly be. In a tempest, however, she must be dismasted, and rowed by fourteen men, with oars 16 feet long, double banked. The men are all fastened to the thwarts by ropes, and can* not be washed from their seats, Explanation of the platp. Explanation of Fig. 1. A, Four copper ventilators, the plate. R The forecastle skuttle. \ £, C, C, C. Four wood scuttles on each side. D. D. The deck that covers the copper cases, wherein seven tons of goods may be put, or other articles, E. Hooks for the life lines, F. Seven life-lines on each side, the ends in the water, floated with cork, by which men may hold that are washe4 from the wreck before they can be taken into the boat. G. The grating in the bottom of the boat.. - H. Three small pump wells. I. The tholes, K. The bitts. L, L. Ropes to fasten the men to the thwarts, Fig. .2. Section of her midship part. M. Five Norway baulks. N, N. The copper cases. Fifif- 3. A perspective view of one of the cases detached. Fig. 4. The stern. O. The rudder on a new principle. P, P. The stern ports to let out the water. Fig. 5. A side view of the boat, to show her sheer. Q,Q. The oars. pN THE ALBURNUM OF TREES, %J v, On the Origin and Office of the Alburnum of Trees. In a Letter from T. A. Knight, Esq. F.R.S. to $ir Joseph Banks, Bart. K. B. P. R. S*. Mr. Dear Sir, , N my last communication I endeavoured to prove, that The bark not the bark of trees is not subsequently transmuted into albur- changed into num ; and if the statements that I have there given be cor- rect, they are, I conceive, decisive on the point for which I .contended : and jf the bark be not converted into alburnum, the experiments of Duhamel, and subsequent naturalists, but deposits and those of which I have given an account in former me- lhe alburnous moirs, afford sufficient evidence, that the bark deposits the alburnous matter. If the succulent shoot of a horse chesr nut, or other tree, be examined, at successive periods in the spring, it will be seen, that the alburnum is deposited, and its tubes arranged, in ridges beneath the cortical vessels; and the number of these ridges, at the base of each leaf, will be found to correspond accurately with the number of apertures through which the vessels pass from the leaf-stalks into the interior bark, the alburnpus matter being apparently deposited (as I have endeavoured to prove in former me- moirs) by a fluid which descends from the leaves, and subse- quently secretes through the barkf . I shall therefore ven- ture to conclude, that it is thus deposited, and shall pro- ceed to enquire into the origin and office of the alburnous tubes. The position and direction of these tubes have induced al- Origin and of- most all naturalists to consider them as the passages through fice of ttief'- , , in r • i burnous tub**, which the sap ascends; and at their nrst formation, when the substance which surrounds them is still soft and succu- lent, they are always filled with the fluid, which has appa- rently secreted from the bark. They appear to be formed in the soft cellular mass? which becomes the future albur- f Philos. Trans, for 1808, Part II, p. 313. f f nil. Trans. J807, p. 33^. num, 28 ON THE ALBURNUM OF TREES. mim, as receptacles of this fluid, to which they may either afford a passage upwards, or simply retain it as reservoirs, till absorbed, and carried off, by the surrounding cellular substance. The former supposition is, at first view, the most probable ; but the latter is much more consistent with the circumstances, that I shall proceed to state. Ascent of the Many different hypotheses have been offered by naturalists ***** to account for the force, with which the sap ascends in the spring; of these hypotheses two only appear in any degree Sausaure's hy- adequate to the effects produced. Saussurejun. supposes, ** that the tubes contract as soon as they have received the sap in the root, and that this contraction, commencing in the root, proceeds upwards, impelling the sap before it: and I and one of Mr. have suggested, that the expansion and contraction of the Kn^ts, compressed cellular, or laminated substance (the tissu cel- lulaire of Duhamel and Mirbel) which expands and con-* tracts with change of temperature* after the tree has ceased to live, might produce similar effects, by occasioning nearly a similar motion and compression of the tubes, the coats of which are, 1 believe, universally admitted not to be mem- inconsistent branous. ' But both these hypotheses are inconsistent with with facts. the facts, that I have now the pleasure to communicate to you. Tubes of an- Selecting parts of the stems of young trees, from which conrtned u>\he annual branches had sprung in the preceding year, I ascer- extemal an- tained by injecting coloured infusions into the stems, through w^wdo^he the anrmal snoots, that the tubes, which descended from the same side, latter, were, at their bases, confined to that side of the stem from which they spring, and to the external annual layer of Thecommunl- wood. Deep incisions were then made into the stems of cation cut off other trees immediately beneath the bases of similar annual somee S ■' shoots, by which I am quite confident, that all communica- tion through the alburnous tubes, with the stem, was wholly cut off: yet the sap passed into the annual shoots in the suc- ceeding spring, all of which lived, and some grew with con- d th t b siderable vigour. I, at the same time, selected many lateral cut through in branches, about three lines in diameter, in a nursery of apple ethers. trees, which I could easily secure to the stems of the adjoin- * ThiJ. Trans. *8o*, p. 345, nig ON THE ALBURNUM OF TREES. g<} ing trees to prevent their being broken. I then made an incision, more than two lines deep in each, on one side, and at the distance of six or seven lines another incision, equally deep, on the opposite side; and as I am quite certain, from the texture of these branches, that the alburnous tubes passed straight through them, I am equally certain, that every alburnous tube was at least once intersected. Yet the sap The sap still passed into these branches, and their buds unfolded in the buds unfolded, succeeding spring, the incisions having been made in the and the winter. But I have repeated the same experiment after the branches llYed- leaves have been full grown in the summer, and still the branches have contiuued to live. All natural ts have agreed in stating, that trees perspire When trees most in the summer, when their leaves have attained their PerfPire mos,t, full growth, and of course that much sap must ascend a.t tubes dry. this period; yet at this period the tubes of the alburnum appeur dry, and to contain air only ; which induced Grew to suppose, that the sap rose in the state of vapour; a suppo- sition by no means admissible. Yet it is, I conceive, evi- The sap there- dent, that the sap cannot rise as a liquid through dry fore does not » 7 T , rise through tubes, nor in any state through intersected tubes ; and there- them. fore it appears probable, that it does not rise at ail through the tube3 of the alburnum, and that these tubes are in- tended to execute a different office. If the sap do not rise through the tubes of the alburnum, Consequently it must rise through the cellular substance; yet the passage Jt must rise of any fluid through this has been denied by almost every cellular sub- naturalist, probably because coloured infusions have not stance. been observed to penetrate it, and because many naturalists have considered it as mere compressed medulla. Mirbel, however, contends, that the fluid which generates the new bark exudes from it; and although a fluid, capable of pro- ducing the same effects, e:tndes from the bark, when de- tached from the alburnum, 1 am much disposed to coincide with him in opinion, having observed a new bark to be ge- nerated on the surface of the cellular substance of pollard oaks, in detached spaces*. And if the sap in sufficient quantity to generate a new bark can pass through the cel- • Phil. Trans. 1607, p. 107 ; or our Journal, vol. XIX, p. 245. lular But coloured infusions will pass through tke cellular Substance. 20 ON TtiE ALBURNUM OF TREES* lular substance of an oak, it appears possible at least* thai Celoured infu- tne whole of the sap may ascend through it. Coloured in- sions not pas- fu9ions do not, 1 think, in any degree* pass through the bark sing, no proof „ . . . - . * , J?« . . , that sap does °* tre^Sj yet it is evident, that the sap passes readily through not. it; and therefore should it be proved, that such infusions do not penetrate the cellular substance of the alburnum* the evidence which this circumstance would afford would be very defective. Among other experiments which I made to ascertain whe- ther the cellu]ar substance of the alburnum would imbibe coloured infusions, I took off branches of two years old with the annual shoots and leaves attached to them, in the sum- mer, from trees of different species ; and I effectually closed the albumous tubes with a composition formed of calcined oyster shells ahd cheese*, and this was covered with a mix- ture of bees wax and turpentine, so as effectually to exclude all moisture. A part of the bark was taken off each branch, in a circle round it, a few lines distant from its lower end, where the tubes had been closed; and each branch was then placed in a decoction of logwood, in a vessel deep enough to cover the decorticated spaces. At the end of twenty hours, or somewhat longer periods, these branches were examined, and the coloured infusion was found to have insinuated itself between the alburnous tubes, in many instances apparently through the cellular substance. This was most obvious in the walnut tree, the young wood of which is very white. The principal object I had in view in making this experi- ment was, to-detect the passages through which I conceived the sap to pass from the bark into the albumumf. From the preceding circumstances, I am disposed tp in- the cellular ^*er» tnat tne saP secretes through the cellular substance of the alburnum; and through this I conceive that it must as- cend, when the tubes were intersected in the preceding ex- periments, and in those seasons of the year when the albur- nous tubes are empty, though the sap must be rising with great rapidity: and I shall endeavour to show, that the p re- Effectual ce- # I have found this composition, and this only, to be capable of in- nient to stop stantaneously stopping the effusion of sap from the vine, or other tree in the bleeding of lhe bleeding season. f Phil. Trans, 1807, p. 107 ; or Journal, XIX, p. 24$. sence The sap se- substance of (he alburnum, ON THE ALBURNUM OF TREES, 31 sence of the sap in the alburnous tubes, during that part of the year in which trees, when wounded, bleed abundantly, does not afford any decisive evidence of the ascent of the sap through those tubes. In the last spring, when the buds of the sycamore first Experiments began to prepare tor unfolding, I found, that the sap ^e*he *T°a* abounded in the points at the annual branches; and at the same time it flowed abundantly from incisions made into the alburnum near the root. But when similar incisions were made at the distance of eight or ten feet from the ground, not the least moisture flowed; and the tubes of the albur- num appeared to contain air only. I also observed, that the sap flowed as abundantly from the upper as from the under side of the lower incisions, if not more abundantly, and so it continued to flow to the end of the bleeding season. The sap must therefore have been, by some means, thrown into the tubes above the incisions, for the quantity discharged from them exceeded more than a hundred times that which the tubes could have contained at the time the incisions were made, even hud every tube been filled to the extremity of the most distant branch. And, as it has been shown, that the sap can pass up when all the alburnous tubes are inter- sected, there appears, I think, sufficient evidence, that it • must in this case have been raised by some other agent than those tubes. Through the cellular substance I therefore venture to con- The sap as- elude that t'oe sap ascends ; and it is not, 1 think, difficult to cends through conceive, that this substance may give the inipulse, with substance. which the sap is known to ascend in the spring. I have shown, that the bark more readily transmits the descending sap towards the roots than towards the points of the branches*; and if the celltflar substance of the alburnum expand and contract, and be so organized as to permit the sap to escape more readily upwards from one cell to another, than in any other direction, it will be readily expelled to the extremities of the branches : and I have shown, that the statement, so ™ r- j • i • • ,» ,. The sap not otten repeated in the writings of naturalists, of a power in transmitted tbe alburnum to transmit the sap with equal facility in op- Wlth e(lual fa* 9 r cihty in oppo- • Phil. Trans. 1804, p. 5 ; ©r Journal, vol. X, p. 292. posite S2 ON THE ALBURNUM OF TREES. posite directions, and as well through inverted cuttings as others, is totally erroneousf. The albumous If the sap be raised in the manner I have suggested, tubes reservoirs much 0f jt w^]| probably accumulate in the alburnum in the spring; because the powers of vegetable life are, at that period, more active than at any other season; and the leaves are not then prepared to throw off any part of it by transpi- ration. And the cellular substance, being then tilled, may discharge a part of its contents into the alburnous tubes, which again become reservoirs, and are filled to a greater or less height, in proportion to the vigour of the tree, and the state of the soil and season: and if the tubes which are thus filled be divided, the sap will flow out of them, and the tree will be said to bleed. But as soon as the leaves are unfolded, and begin to execute their office, the sap will be drawn from its reservoirs, and the tree will cease to bleed, if wounded. These tubes The alburnous tubes appear to answer another purpose in are analogous trees an(j to be analogous, in some decree, in their effect*, to the cavities . . . , . '.. in bones, in- to the cavities in the bones of animals; by which any de- c5easJJ1F • h gr.ee of strength, that is necessary, is given with less expen- out weight, diture of materials, or the encumbrance of unnecessary weight; and the wood of many different species of trees is thus made, at the same time, very light, and very strong, the rigid vegetable fibres being placed at greater distances from each other by the intervention of alburnous tubes, and con- sequently acting with greater mechanical advantage, than they would if placed immediately in contact with each other. The air in the J nave shown in a former communication, that the specific alburnous „ . . . , . .-, tubes conduces gravity ot the sap increases during its ascent in the spring, to the produc- and that saccharine matter is generated, which did not pre- tion of sugar, vjousiy. ex-gt jn ^e alburnum, or in the sap, as it rose from the root: and I conceive it not to be improbable, that the air contained in the alburnous tubes may be instrumental in as when apples tne generation of this saccharine matter. For I discovered are ground to in the last autumn, that much air is absorbed, or at least m eci er, disappears, during the process of grinding apples for the purpose of making cider, and that during this absorption of • Phil. Trans, 1804, p. 5 j or Journal, vol. X, p. *9t. aic ON POLYGONAL NUMBERS. 33 air, the juice of acid apples becomes very sweet, and ac- quires many degrees of increased specific gravity; and a si- milar absorption of air, with corresponding effects, is well andinmalting. known to take place in the process of malting. I shall conclude with observing, that in retracting the Subsequent B . ^ r motion of opinion 1 formerly entertained respecting the ascent ot the the sap sap in the alburnous tubes, I do not mean to retract any through the ...iT1 ..„ . . central vessels. opinion that 1 have given in former communications re- leaves &batk;. specting the subsequent motion of the sap through the cen- tral vessels, the leaves, and bark ; or the subsequent junction of the descending with the ascending current in the albur- num: every experiment that I have made has, on the con- trary, tended to confirm my former conclusions. I am, My dear Sir, Your much obliged obedient servant, THOMAS ANDREW KNIGHT. Elton, June 15, 1808. VI. Letter on Polygonal Numbers, in Reply to Mr. Gough: by P. Barlow, Esq. To the Editor of the Philosophical Journal. SIR, .R. Gough is perfectly correct in stating, that I was in Re j to Mr< possession of his reply previous to the date of my letter Gough. inserted in your Journal. The reason I did not think pro- per to publish it was, that it was written in answer to a pri- vate letter, which was not exactly the same in form as that published in your number for October, and consequently an answer to the former could not with propriety have been given as a reply to the latter. I must now beg leave to be permitted to make a few re- marks on the answers of Mr. Gough inserted in your last Vol. XXII. — Jan. I8O9. D number; 34* ON POLYGONAL NUMBERS. GouV0^ number; tnis gentleman has divided ray paper into three objections, which he has pronounced to be futile, and I must add without proving them to be so. Mr. Gough will recollect, that in my letter, so far as related to the first four propositions and their corollaries, I did not object to the conclusion, but to the manner of obtaining it; my object was only to show, that an unnecessary number of proposi- tions and corollaries were introduced into the essay, to de- monstrate that which needed no demonstration. Mr. Gough does not deny this, except that 1 have called that a postulate, to which I have given the importance of; a theorem, and de- monstrated it as such ; it is true, as it stands in my letter, it has the appearance of a proposition, but it was unneces- sary to give it this form : it might have stood thus ; Definition. Unity is a polygon of every denomination. Postulate. Let it be granted, that every integer is an ag- gregate of units, or of polygonals. Here it is evident that no demonstration is necessary, and had Mr. Gough begun his essay with this postulate, he would at all events have saved himself and readers consider- able trouble. My third, and only objection that effects the truth of the demonstration, Mr. Gough has evaded, by charging me with putting a false construction upon his words; and now I am under the necessity of retorting the charge. I never said, nor intended to say, that it was necessary to show, that e ~y + t can be resolved into m -~-f polygon in all cases ; the question which I proposed was this; " If e r: y -f- 1 cannot be resolved into m —>/ polygons, how does it appear from the demonstration, that e + f can be resolved into m polygons ?" This question I again repeat, and unless it can be satisfactorily answered, the theorem will be still with- out a demonstration, however unwilling Mr. Gough may be to acknowledge it. This gentleman must also be aware, that he cannot be allowed to introduce his examples, which are the moment before derived from the demonstration, to prove the truth of the supposition on which that demonstra* tion is founded. Mr. Gough appears to have deceived himself by consi- dering only small numbers, in which the polygons, being 1 also ON THE STRUCTURE OF CALCULI. 35 ttlso small, are commonly some of them equal to y, m or Reply to Mr. unity; let him take a larger number, for example 1520, and oug ' resolve into squares; now e~ 1520, y sz 1444, and t zz 19 m; .whereas his demonstration does not include numbers higher v , than those of the form e zz y -f 2 m. It is not my intention to pursue this argument any far- ther, because however curious the theorem may be as relat- ing to the indeterminate analysis, it is perhaps uninteresting to the greater part of your correspondents. If therefore, Mr. Gough undertake to answer this question, I shall leave it for your mathematical readers to decide for themselves, how far it may be considered as satisfactory. Yours, &c. Royal Military Academy, P. BARLOW. Dec. 9, 1808. VII. A Letter on the Differences in the Structure of Calculi, which arise from their being formed in different Parts of the Urinary Passages; and on the Effects that are produced upon them, by the internal Use of solvent Medi* cines, from Mr, William Brande to Everard Home, Esq. F.R.S. Dear Sir, H. AVING availed myself of the opportunity you pro* Calculi in the cured for me of making a chemical examination of the cal- Huntenan culi contained in the Hunterian Museum, as well as those Mr. Homes in your own collection, I herewith send you an account of what I have done. Should the observations appear to you to throw any new light upon the formation of calculi, I request, that you will do me the honour of laying them before the Royal Society. The collection, which I have examined, is not only un- very numer- commonly large, but the greater part of the specimens have ous> anc! iu 6^ histories of the case annexed to them. I> 2 This 3() ON THE STRUCTURE OF CALCULI. their histories This circumstance enabled me not only to ascertain the annexed. situations in which the calculi were found, but likewise many of the circumstances attendant on their formation. I have therefore endeavoured to form an arrangement upon these principles, with a view to render the subject more clear and perspicuous. Sect. I. Of Calculi formed in the Kidnies, and voided without having afterwards undergone any Change in the uri- nary Passages, Calculi of the These have the following properties : They are of a brownish yellow colour, sometimes of a grayish hue, which seems to arise from a small portion of dry mucus adhering to their surface. They are entirely soluble in a solution of pure potash, and during their solution they seldom emit an odour of am- monia. When heated to dryness, with nitric acid, the residuum is of a fine and permanent colour. Contain animal When exposed to the action of the blow-pipe, they black- matter. en antj emjt a gtrong odour of burning animal matter, very different from that of pure uric acid. This arises from a variable proportion of animal matter which they contain, and which occasions the loss in the analysis of these calculi. Its relative quantity is liable to much variation, as may be seen from the following statements, A calculus from the kidney, weighing seven grains, was dissolved in a solution of pure potash. A quantity of muri- atic acid (rather more than sufficient for the saturation of the potash) was added, ami the precipitate of uric acid thus obtained weighed when dry 4'5 grains. No other substance, except animal matter, which was evident on at- tempting to obtain the muriate of potash, could be detect- ed, consequently the composition of this calculus was as follows: Grs. Uric acid • 4*5 Animal matter 2*5 7-0 This ON THE STRUCTURE OF CALCULI. 3J This is the largest proportion of animal matter which I have met with. A small calculus from the kidney, weighing 3*7 grains, Sometimes in afforded by a like treatment 3-5 grains of uric acid, so that T^J^f11 it was nearly a pure specimen of that substance. The largest calculus of this kind which I have examined weighed seventeen grains ; much larger ones have been found, but there is no evidence of their not having remained in the urinary passages for some considerable time. Thus Dr. Heberden mentions one weighing twenty-eight grains*. It often happens that the ingredients are not united toge- Sand, ther so as to form a calculus, but are voided in the state of a fine powder, commonly termed sand. This consists either phosphates of uric acid, or of the ammoniaeo-magnesian phosphate, found in this, alone, or with the phosphate of lime. I am induced to believe, that the last mentioned sub- *wt n°t in the stances, although the production of thekidnies, and held in solution, are never met with in a separate state, till the urine has been at rest, and therefore calculi from the kidnies are never composed of the phosphates. In a few instances, calculi from the kidnies composed of pxalateof oxalate of lime are voided ; *but this is a very rare occurrence. lime* Of three preserved in the Hunterian collection, two are ex- tremely small and hard, having an appearance of being made up of several smaller calculi, of a dark brown colour. The third is of the size of a small pea, its surface smooth, and of a gray colour, not very hard. Sect. II. Of Calculi which have been retained in the Kidney. When one or more of the calculi described in the preced- Calculi detain- ing section are detained in the infundibula or pelvis of the nem * e kidney, it frequently happens, that they increase in that si- tuation to a considerable size. This increase is of two kinds. I. Where there is a great disposition to the formation of uric acid, the calculus consists wholly of that substance and animal matter, so as frequently to form a complete cast of the pelvis of the kidney. * Comment on the Hist, and Cure of Diseases, 3d. edit. p. 88. 2. Where 38 ON THE STRUCTURE OF CALCULr. Phosphates in 2. Where there is less disposition to form uric acid, the external laminae are composed of the ammoniaco-magnesiah phosphate, and phosphate of lime. In one instance, a small uric calculus has been deposited in the kidney in such a situation, that its upper surface was exposed to a continual stream of urine, upon which beauti- ful crystals of the triple phosphate had been deposited. It would therefore seem, that, under common circumstances, a stream of urine* passing over a calculus of uric acid has a tendency to deposit the phosphate upon it. Sect. III. Of Calculi of the urinary Bladder. Calculi of the Calculi met with in the bladder are of four kinds. bladder. 1# Those formed upon nuclei of uric acid from the kid- ney. 2. Those formed upon nuclei of oxalate of lime from the kidney. 3. Those formed upon sand, or animal mucus, deposited in the bladder. 4. Those formed upon extraneous bodies introduced into the bladder. They were arranged under the following divisions. Calculi of uric 1# Calculi, which, from their external appearance, con- acid chiefly, sist chiefly of uric acid. These calculi vary in colbur from a deep reddish brown, to a pale yellowish brown. They are either entirely soluble in a solution of pure pot- ash, or nearly so. During their solution they frequently emit the pdpur of ammonia. When acetic acid is added to their alkaline solution, a precipitate possessing the properties of uric acid is obtained. Calculi of 2. Calculi composed chiefly of the ammoniaco-magne- phosphates sian phosphate, or of phosphate of lime, or of mixtures of chiefly. . - ■ the two. These calculi are externally of a whiter appearance than the former. Some perfectly white, others gray, occasionally exhibit- ipg small prismatic crystals upon their surface; others again soft and friable, a good deal resembling chalk; They are, ON THE STRUCTURE OF CALCULI. 39 N are farther characterised by their solubility in dilute muri- atic acid. 3. Calculi containing oxalate of lime ; commonly called W"1,?1 oxalat« ., . .. D f of hme, or mulberry calculi. mulberry eai- - These are distinguished by the difficulty with which they culi- dissolve in dilute acids, by their hardness, and by leaving pure lime, when exposed to the action of the blowpipe. In the examination of these calculi, I was struck with the small number of those strictly belonging to the first divi- sion, having been led, from the account of Fourcroy and Vauquelin*, and the experiments of Dr. Pearsonf, to be- lieve that calculi, composed of pure uric acid, were by no means unfrequent. The greater number of the calculi examined by the for- mer chemists are stated to be completely soluble in the fixed alkaline lies; and of three hundred examined by Dr. Pearson, a large proportion is said to consist of uric acid. The following is a statement of the composition of the Composition different calculi found in the bladder which I have exa- of different . calculi. mined. 16 were composed of uric acid. 45 , uric acid with a small relative pro- portion of the phosphates. 66 i.i the phosphates, with a relatively small proportion of uric acid. J 2 1 . ■ of the phosphates entirely. 5 ■ . — • of uric acid, with the phosphates and nuclei of oxalate of lime. 6 ■ chiefly of oxalate of lime. 150 - To injure these calculi as little as possible, they were Sawn in two carefully cut through with a fine saw, and a portion of the an<* a portion whole cut surface removed by a file ; in this way all the dif- ° ' ferent ingredients of the calculi were obtained. In the experiments upon uric calculi from the bladder, I More loss from found, in most instances, a far more considerable loss in at- tllose ©f toe * Annales de Chimie, xxxii, ai8. •fr Philos. Trans. 1798. p. 37. tempting 40 bladder than those of the kidney. One supposed to consist of yrate of am- monia digested in water. Solution eva- porated. Another di- gested in alco- hol. Solution eva- jporatecj. ON THE STRUCTURE OF CALCULI. tempting to obtain their pure uric acid, than in the kidney calculi, which led me to suppose, that they contained ureal and that the presence of this substance, with some of the salts of urine, and with small portions of the ammoniaco- magnesian phosphate, was the cause of the occasional evo- lution of ammonia when treated with the fixed alkalis, and of their easy solubility in those substances. To determine this point, a small calculus, weighing twenty-five grains, and of the species commonly supposed to consist of urate of ammonia*, was digested for two hours with water in a very moderate heat. The water which had assumed a pale yellow colour was filtered off, and fresh water added to the residuum three successive times, when it appeared, that every thing soluble in that fluid was sepa* rated. The insoluble part of the calculus, being now care^ fully dried and weighed, was found to have lost 5*5 grains. The aqueous solution was evaporated by a gentle heat, nearly to dryness, and a substance was obtained having all the properties of urea, in combination with a small portion of muriate of ammonia, and of the ammoniaco-magnesian phosphate. Sixty grains of another calculus of a considerable size, supposed from a superficial analysis, to consist of nearly pure urate of ammonia, were digested at a low temperature in one ounce of alcohol. In an hour the alcohol was decanted off, and fresh portions were added successively, as long as it appeared to act upon the calculus, which, after having been carefully dried in a temperature below 212°, weighed 54«8 grains, so that 5*2 grains had been taken up by the al* cohol. On evaporating the alcoholic solutions, a substance was obtained having all the properties of urea, with a small por-r tion of saline matter, probably muriate of ammonia, as by the addition of potash a slight ammoniacal odour was per- ceptible; its quantity however was too minute for accurate examination. • Fourcroy observes, that urate of ammonia is easily detected by it* tapid solubility in the fixed alkalis, and the odour of ammonia, which is perceived during its soluticn.-»Vide Thomson's Svst. of Chem. vol. v, *65t- Th, OTf THE STRUCTURE OF CALCULI. 4j| The remaining portion of the calculus, weighing 54*8 Treated with grains, was treated with small portions of acetic acid, by ace *° aci * which 6 grains of the amraoniaco-magnesian phosphate were obtained. - The part of the calculus remaining after this treatment, Residuum dis- weighing 48*8 grains, was perfectly soluble in a solution 0f sojved in pot- pure potash ; it emitted no ammoniacal odour when acted upon by the alkali, and possessed the properties of pure uric acid. The following therefore is the composition ofyhis calculus. Component part*. Grains. Urea, and muriate of ammonia .... 5*2 Ammoniaco-magnesian phosphate • • 6* Uric acid • • • • 48*8 60- From these and many similar experiments upon other No urate of calculi, hitherto generally supposed to consist of urate of ammoniaina** ammonia, I am induced to believe, that the evolution of ammonia depends in all instances upon the decomposition of the ammoniacal salts contained in the calculus, more es- pecially of the ammoniaco-magnesian phosphate, and that no substance, which can be called urate of ammonia, exists in calculi. The mulberry calculus (oxalate of lime) I have but rarely Mulberry cat- met with. In those preserved in the Hunterian Collection culi* there is a large relative proportion of phosphate of lime, and. of uric acid. The purest of them afforded Grs. Oxalate of lime 65* Uric acid iQ» Phosphate of lime 15» Loss in animal matter • • • • 4# 100* When calculi of the urinary bladder increase to a very large very large cal- size, they are generally composed of two or even three of culi seldom the above mentioned varieties, the ammoniaco-magnesian omoSeneous« phosphate 42 °N THE STRUCTURE OF CALCULI. phosphate being situate «xternally, and in the greatest abun- dance. One of 23 02. The largest calculus, whiah I have seen, weighed, when z6grs. recently removed from the bladder, twenty-three ounces and twenty-six grains. It consisted of a large mulberry or oxalate of lime calculus, the nucleus of which was uric acid, surrounded by a considerable quantity of the ammo* niaco-magnesian phosphate in a very pure state. Oneof J5|oz. Another very large calculus, weighing fifteen ounces and a half, consisted of a nucleus of uric acid, enveloped in the ammoniaco-magnesian phosphate, not however pure, but in- tersected by several laminae of uric acid. Four distinct substances are extremely rare in calculi; I Four distinct have seen one in which the uric acid, the ammoniaco- mag- ♦ubstances nesian phosphate, the phosphate of lime, and the oxalate of lime, were all in perfectly separate and distinct layers. Four calculi, having the following extraneous substances Four formed for their nuclei were examined. «wr foreign nu- \, A common garden pea. cJei, 2. A needle. 3. A hazel nut. 4. A part of a common bougie. In the two first instances, the calculous depositions were of a pale gray colour, inclining to white; soft and friable in their texture, and entirely soluble in muriatic acid. The composition of the first was as follows; Grs. Phosphate of lime • 65 • Ammoniaco-magnesian phosphate* • 28* Loss • • • • • • • 7# 100- Of the second ; Phosphate of lime » • * 45* Ammoniaeo-magnesian phosphate •• 38* Oxalate of lime ] £• Loss • • « 5* 100 * * It appears, that in this case there had been an accidental disposition to the formation of oxalate of lime. The ON THE STRUCTURE OF CALCULf. 43 The deposition of calculous matter upon the bougie was covered with blood, and in very small quantity, the bougie having been removed by an operation soon after it bad passed into the bladder. It appeared to consist chiefly of -phosphate of lime. The incrustation upon the hazel nut was also destitute pf uric acid. Sect. TV. Of the Calculi of the Urethra, All those that were examined had escaped from the blad- Calculi of the der while very small, and had afterward lodged in the mem- jbranous part of the urethra, where they had increased in size, and formed a cavity, in which they were more or less imbedded. Two of these calculi were broken. The fragments consisted in one instance of ammoniaeo- rnagnesian phosphate, and phosphate of lime, with a small portion of uric acid: and in the other the fragments were composed entirely of the ammoniaco-magnesian phosphate? The third calculus was of a very remarkable appearance; its form being that of a perfect sphere, about half an inch in diameter. It was coated with small but very regular crystals of the triple phosphate in its purest state. On ac- count of the singularity of the form and external appear- ance of this calculus, it was not sawn through; the nucleus, in all probability, is a small kidney calculus, which lodging in the urethra has become coated with triple phosphate. Sect. V. Analysis of Calculi from other Animals. J. The horse. Calculi of the A. From the kidney. horse. A very large calculus, from the kidney of a horse, was From the kid- pomposed of neY* Phosphate of lime » 76 Carbonate of lime ................ 22 98- B. From the bladder* This calculus was also of a large size; its weight, when From the Mad- perfectly dry, nine ounces and a half; its external surface der* very ££ ON THE STRUCTURE OF CALCULI, Tery irregular, of a reddish brown colour, and covered with minute crystals of the aminoniaco-magnesian phosphate. On making a section of it, the internal structure exhibited a radiated appearance, and was of a light brown colour. It consisted of Phosphate of lime • • • • 45* Amraoniaco-magnesian phosphate •• 28* Animal matter 15. Carbonate of lime ] o* 98- In another case the bladder of a horse was found to be nearly full of sand, the composition of which was as follows ; Phosphate of lime • 60* Carbonate of lime 40* 10Q- Calculi of the 2. The ox. A number of small calculi, from the size of a pea down- wards, are not unfrequently found in the bladder of the ox. Those in the Hunterian Collection are of a pale brown co- lour, and of the size just mentioned ; some of them have the mulberry appearance. They consist of carbonate of lime and amimal matter, which last substance retains the form of the calculus, after it has been acted upon by diluted acids. Of the sheep. 3> The sheep. A calculus from the kidney of a sheep was composed of Phosphate of lime • 72* Carbonate of lime 20* Animal matter 8* 100- Of the rhino- 4. The rhinoceros. The urine of this animal is exceedingly turbid at the time it is voided, and when allowed to remain at rest, depo- sites a very large proportion" of sediment, which consists of carbonate of lime, with small portions of phosphate of lime and animal matter. 5. The eeros. ON THE STRUCTURE OF CALCULI. 4£ 5. The dog. Of the dog. A large calculus from the bladder of a dog twenty years old, weighing sixteen ounces, was extremely hard, and of a gray colour ; when cut through, it exhibited a nucleus about the size of a hazel nut, partly made up of concentric layers of phosphate of lime, and partly of crystals of the amino* niaco-magnesian phosphate. The part of the stone sur- rounding the nucleus consisted of Phosphate of lime • 64* Ammoniaco-magnesian phosphate • • 30' Animal matter 6' 100' Sand taken from a dog's bladder was of a gray colour, and contained Carbonate of lime ......••••• 20* Phosphate of lime 80* 100* 6. The hog. Of the hog. A calculus from the bladder of this animal weighed nine- teen drachms; it was of a pale gray colour inclining to white, and so hard that it was with difficulty cut through. Its internal structure was uniform, .and there was no appear- ance of a nucleus. It was composed of Carbonate of lime* •••.....• go* Animal matter io» ^100- 7. The rabbit. Of the rabbit A calculus from the rabbit's bladder weighing four drachms, was of a dark gray colour, and appeared as if com- posed of several smaller calculi. It consisted of Phosphate of lime 39* Carbonate of lime 42» • Animal matter . • • 19* 100« Sect. the stone in the bladder. 46 ON THE STRUCTURE OF CALCULr. Sect. VI. General Inferences. General con- It appears from the preceding observations, that calculi elusions. formed in the kidnies, and immediately voided, are almost always composed of uric acid ; and that the phosphates are very frequent ingredients in calculi of the bladder, more especially in those, which, from their situation, have been exposed to a continual current of urine : they also uniformly are deposited upon extraneous substances introduced into the bladder, but appear never to form small kidney calculi. Fit of the ^n wnat *s commonly called a fit of the gravel, a small gravel. uric calculus is formed in the kidney, and passes along the ureter into the bladder. Formation of It is found from observation, that for some time after a stone has passed from the kidney, the urine is generally un- usually loaded with uric acid, and deposites that substance upon the nucleus now in the bladder. When this period, which is longer or shorter in different individuals, has elapsed, the subsequent addition to the calculus consists principally of the phosphates. Where the disposition therefore to form uric acid in the kidnies is very great and permanent, the calculus found in the bladder is principally composed of uric acid ; but where this disposition is weak and of short duration, the nucleus only is uric acid, and the bulk of the stone is composed of the phosphates. Wrhere the increased secretion of uric acid returns at in- tervals, the calculus is composed of alternate layers of uric acid and the phosphates. Other small calculi being formed in the kidney, they make their way into the bladder, and afford fresh nuclei; so that several calculi are sometimes found in the same blad- der, and their composition is usually nearly the same. In other cases it happens, that a constant increased secre- tion of uric acid is going on from the kidnies, only in small quantity, which will be more uniformly mixed with the phosphates deposited in the bladder, and where the uric acid predominates, the species of calculus, denominated impro- perly urate of ammonia, will be produced. F rmationof ^e ave ent*rely ignorant of the cause of the formation of ON THE STRUCTURE OF CALCULI. 47 #ie oxalate of lime, or mulberry calculus. I have fre- thf mulberry quently looked for oxalate of lime in the urine of calculous patients, but have never been able to detect it ; and as it does not exist in healthy urine, it must be regarded as a morbid secretion. Its mode of formation seems to resemble that of uric acid, since small kidney calculi, composed of oxalate of lime, have in a few instances been voided ; and in these cases, as far as my own inquiries go, the persons have been much less liable to a return of the complaint, than where uric calculi have been voided. In some rare instances we meet with calculi of the blad- der which are destitute of uric acid, and of oxalate of lime, the nucleus being composed of a little loosely agglutinated ammoniaco-magnesian phosphate, and the whole calculus consisting of that substance, with variable portions of phos- phate of lime: in two cases I have met with calculi of this kind, composed of the triple phosphate only : they seem to be entirely formed in the bladder. Having taken this short view of the formation of calculi, Action gf«c&* I shall now inquire into the action of solvents, employed vents' either with a view of effecting their solution, or of prevent- ing their formation and increase. Solvents are of two kinds. 1. Alkaline. 2. Acid. In the exhibition of these, the practitioner is usually guided by the chemical composition of the calculous mat- ter voided by urine. The different kinds of gravel, voided by persons labour- Gravel of i*e ing under calculous complaints, may be classed in two di- kmd$' visions. 1, Uric acid, either in a pure state, or with a very small proportion of the phosphates. 2. The phosphates, either pure, or with a small propor- tion of uric acid. The first species, which generally appears in the form of Uric aeii. minute crystalline grains, of a reddish brown colour, or of an impalpable brown powder, is either entirely soluble in pure alkaline solutions, not emitting an ammoniacal odour, in which case it consists of pure uric acid : or it does emit an ammoniacal odour, aud is not entirely soluble, in which case 48 ON THE STRUCTURE OF CALCULI. case it contains the triple phosphate of ammonia and mag- nesia. Effect of alka- When this substance is observed in the urine, the alkalis Ms. are recommended. They are exhibited either in a pure' state, or as carbonates, and in each instance the uric sedi- ment generally diminishes rapidly, and during the continued use of alkaline medicines, occasionally disappears altoge- ther. It however frequently happens, that the matter voided is not diminished in quantity by the use of alkalis, but that its form and composition are altered, and that it assumes the appearance of a gray powder, and is composed of uric acid, with variable portions of the ammoniaco-magnesiau phosphate. Prevent the in- From these facts therefore it cannot be doubted, that the crease of a cal- internal exhibition of alkalis often prevents the formation of uric acid, and hence must likewise prevent the increase of a calculus in the bladder, as far at least as uric acid is con- cerned; but it has also been supposed, that the alkalis are capable of acting upon the stone itself, and even of efTect- Caustic alkali ing its complete solution. It is true, that, if we immerse a dissolves a cal- calculus composed of uric acid in a dilute solution of caus- the bladder. t\c alkali, it will be slowly acted upon, and after some time entirely dissolved. If however we attend to what would take place in the body, we shall find the circumstances very different. Alkaline car- That alkaline carbonates and subcarbonates exert no ac- bonatesdonot. tjon upon uric acid, I consider to be completely established, both by the experiments of several eminent chemists, and Alk li th e ^ose 1 have myself made upon the subject; and as there is fore cannot act at all times a quantity of uncombined acid in the urine, it in t£f bladder follows» tnat> although the alkali may arrive at the kidnies in its pure state, it will there unite with the uncombined acid, and be rendered incapable of exerting any action npon the calculus in the bladder. Beside phosphoric acid, the urine always contains a quantity of uncombined carbonic acid ; this is proved by placing a quantity of recently voided urine under the receiver of an air pump; during the ex- haustion, a large quantity of carbonic acid gas makes its escape : and when urine is distilled at very low temperatures* carbonic ON THE STRUCTURE OP CALCULI. 4# carbonic acid gas is given off: and also, when lime water is poured into urine, a precipitate appears, consisting of phos- phate and carbonate of lime. Lime water, on account of the insoluble compound which JjJJJJJjJJJ lime forms with carbonic and phosphoric acids, is even more tionable. objectionable as a solvent, than the alkalis. It may however be said, that, if these means prevent the Howfarpalli- increase of a calculus, material relief is afforded to the pati- atlVe' ent. How far the exhibition of alkaline remedies can be recommended upon these grounds will appear, when the cir* cumstances, which attend the formation of the second spe- cies of calculous sediment or deposition in the urine, are considered. The ammoniaco-magnesian phosphate appears Under two Ammoniac^ forms : it is either voided in a solid state, or in solution. In SJJttl the former case it bears a good deal of resemblance to a white sand, and is frequently mixed with variable proportions of phosphate of lime. In the latter it makes its appearance after the urine has remained undisturbed for some hours in an open vessel, generally in the form of a fine pellicle, or of crystalline laminae, which when collected and dried bear some resemblance to boracic acid. Its putting on this form is accounted for, from its being held in solution in the first instance by carbonic acid, and as this flies off, the triple salt makes its appearance. If a por- tion of the urine be preserved in a phial closely stopped, the carbonic acid cannot escape, and consequently no phosphate is observed to separate. There is also a quantity of phos- phoric acid present, which keeps another portion of the am- moniaco-magnesian phosphate, and also some lime (in the state of superphosphate of lime) in solution. It is therefore obvious, that, whenever the urine is de- Injurious «f- prived of a portion of the acid which is natural to it, the ecW ° *' deposition of the triple phosphate, and phosphate of lime, more readily takes place : this is effected by the exhibition of the alkalis. It may therefore be asserted, that, altjhougb alkaline me- dicines often tend to diminish the quantity of the uric acidr fnd thus to prevent the addition of that substance in its pure Vol. XXII.— Jan. 1809. £ state 50 ON THE STRUCTURE OF CALCULI. Vse of acids. •tate to a calculus in the bladder ; they favour the deposi- tion of the phosphates. They reach the It cannot be doubted, that the alkalis reach the bladder, bladder. . ' since in cases where large doses of subcarbonate of petash have been exhibited, I have seen evident traces of it in the urine. Where the phosphates only are voided, it has been pro* posed to dissolve the calculus by the exhibition of acids, and more especially the muriatic acid. During the use of the muriatic acid, the phosphates are either diminished or disappear altogether ; and even some- times the urine acquires an additional acidity ; a solution of that part of the calculus, which consists of the phosphates, might therefore be expected; but even then the nucleus of uric acid would remain, and thus a great deal of time would be lost without any permanent advantage. I have also occasionally remarked, that during the use of acids, the uric acid reappears, and even seems to be aug- mented in quantity. Attempts have been made at different times to effect the solution of calculi, by the injection of solvents into the blad- der. This subject has been more lately revived by Four- croy and Vauquelin, who, in their paper on the composition of calculi, lay down rules for its practice. Independent, how- ever, of the impossibility of ascertaining the composition of the calculus with sufficient accuracy, it is obvious, that were the composition of the surface of the calculus known, the frequent introduction of an instrument into the bladder, and the long continuance of the process which would be neces- sary, even where the calculi are small, are insurmountable objections; and whenever this mode of treatment has been adopted,, it has speedily been relinquished, as it always ag- gravates the sufferings of the patient. It has been shown, that, in the majority of cases, the nu- Injection of solvents. Seal use of al- kalis. clei of calculi originate in the kidnies, and that of these nu- clei by far the greater number consist of uric acid; the good effects therefore, so frequently observed during the use of an alkali, arise, not from any actual solution of calculous mat- ter, but from the power which it possesses of diminishing the secretion of uric acid, and thus preventing the enlargement of ON THE STRUCTURE OF CALCULI. 51 of the calculus, so that, while of a very small form, it may- be voided by the urethra. VIII. Some Observations on Mr. Brande's Paper on Calculi. By Everard Home, Esq. F. R* 5*. JL HAT calculi in the human bladder are not dissolved by Inefficacy of the internal use of alkaline medicines, is an opinion which cines"6 "^ 1 have long entertained, but the grounds of failure, so clearly pointed out by Mr. W. Brande, were not known to me: I only knew from expeiu-mce, that, to whatever extent the medicines are given, no such effect: takes place. The cir- Ground of the cumstance of the exterior laminae of calculi extracted from nton^ °P patients, who had persevered in a course of alkaline prepar- ations, having been found softer than the parts towards the centre, has always been considered as a proof of the action of the medicines upon the calculus, and led to the belief,- that where the stone was small, it might be wholly dissolved. This, however, Mr. W. Brande has now proved to be a de- a deception, ception, and that the soft part is not a portion of the original calculus, but a newly formed substance, in which the uric acid is not deposited in crystals, but mechanically mixed with the phosphates and the animal mucus in the urine. Having met with cases, which confirm Mr. W. Brande's Cases confirm observations, it will be satisfactory to state them, as they l 1S* may assist in doing away many erroneous notions generally entertained on this subject. The opinion, that calculi in the human bladder have been Apparently entirely dissolved, has received its principal support from dencf ^^ instances having occurred, and those by no means few in number, where the symptoms went entirely away while the patients were using alkaline medicines, and never afterward returned. This evidence appears to be very strong, but it a mere fallacy, will be found from the following cases, that it is not so in reality; since the fallacy has been detected in all the in- stances in which an opportunity was afforded of examining * Phil. Trans, for 1808, p. 244. E 2 the 52 OV THE STRUCTURE OF CALCULI. the bladder after death. Two of these I shall particularly notice, because they were published during the patient's life time in proof of the stone having been dissolved. Case illuitrat- Both patients were great sufferers from the symptoms of * l$' stone for many years ; but when they arrived at the age of sixty-eight, or thereabout, the symptoms entirely left them. The one had been taking the saline draught in a state of ef- fervescence, under the direction of the late Dr. Hulme : the cure was attributed to this medicine, and the case was pub- lished in proof of its efficacy. When the patient died, I examined the bladder, and found twenty calculi ; the largest ©f the size of a hazel nut, the others smaller. It appeared, that the going off of the symptoms had arisen from the pos- terior lobe of the prostate gland having become enlarged (a change which it frequently undergoes about that period of life,) and having formed a barrier between the calculi and the orifice of the bladder, so that they no longer irritated that part either in the act of making water, or in the different movements of the body, but lay in the lower posterior part ©f the bladder without producing any disturbance. Their number prevented the pressure from being great upon any one part of the intestine immediately behind the bladder, and their motion on one another rendered their external sur- face smooth, and probably prevented their rapid increase. Awtliert The other patient was under a course of Perry's lixivium ; and when the symptoms went away, he published the case in proof of the efficacy of that medicine in dissolving the stone. I examined the bladder after death, and found fourteen cal- culi ; the largest of the size of a nutmeg, the others smaller. There was the same enlargement of the posterior lobe of the prostate gland, and the calculi were exactly under the same circumstances as in the former case. ^n several cases 1° several cases, in which I have examined the body after «tonej not felt, death, calculi have been found enclosed in cysts, formed be- tween the fasciculi of the muscular coat of the bladder, so as to be entirely excluded from the general cavity, and there- fore had not produced any of the common symptoms of stone. I have seen in the same bladder, two, three, and even four such cysts, each containing a calculus of the size of a walnut* It ON THE STRUCTURE OF CALCULI. 53 It is a circumstance deserving notice, that in the case, Mrs. Stevens, which gave celebrity to Mrs. Stevens's medicine, and procur- ed her a remuneration from Parliament, the bladder was not examined after death. That calculi in the bladder do sometimes increase, while Calculi some- the patient is using alkaline medicines, is fully proved by d™J^ » the ass the following examples, which also show, that the uric acid of alkalis, and phosphates are formed in different proportions, accord- ing to the peculiarities of the constitution. A gentleman who suffered from symptoms of stone was founceofthis. sounded, and a stone was found in his bladder. I put him on a course of alkaline medicines, and he voided a small compact calculus, composed of uric acid, and evidently formed in the kidney. He wa6 desired to persist in the use of the medicines, which he did at intervals for four or five years, suffering occasionally in a slight degree, but he did not pass any more calculi. He died at the age of seventy- five. On examining the bladder, its whole cavity, (the ca- pacity of which was equal to a pint measure) was completely filled with soft, light, spongy calculi, three hundred and fifty in number, and of different sizes, from that of a walnut to a small pea. They were composed of a mixture of uric acid in powder, the phosphates, and animal mucus; and differed so much from the calculus voided soon after the patient be- gun the use of alkalis, that they appear to have been form- ed after that period in the manner mentioned by Mr. W. Brande. A gentleman, who was found to have a stone in his blad- Another, der, was persuaded, that it was so small, that it might be dissolved, and with this view he took the fossil alkali, both in its caustic and mild state, for about three months ; but at the end of that period the symptoms were increased, and he submitted to have it extracted by an operation. On ex- amining the calculus after it was extracted, the external part, for the thickness of TV of an inch, was entirely com- posed of triple phosphate, in a state of perfect spiculated crystals, so as to present a very rough irritating surface to the internal membrane of the bladder, while the inner parts of the calculus were made up of a mixture of uric acid and phosphates, so that the alkali had prevented, the formation of 54 AMALGAM PRODUCED PROM AMMONIA. of uric acid, but the phosphates were deposited more rapidly than before. v Alkalis do not A gentleman, in whose urine the uric acid appears in a always coun- .. , r . ,. Il teract the sond iorm immediately alter it is voided, has the same ap^ formation of pearance in the urine, even when nine drachms of soda dis- solved in water impregnated with carbonic acid are taken in twenty-four hours; so that in this instance the alkali does not even counteract the formation of uric acid. of ammonia. IX. Electro-Chemical Researches on the Decomposition of the Earths; with Observations on the Metals obtained from the alkaline Earths, and on the Amalgam procured from Ammonia. By Humphry Davy, Esq. Sec. K. S. M. R. LA. {"Concluded from Vol. XXI, p. 3S3.J V. On the production of an Amalgam from Ammonia, and on its Nature and Properties. Deoxidation Jl N the communication from Professor Berzelius and Dr. SonoTtlK?"111" P°ntm> which I have already referred to, a most curious compound base and important experiment on the deoxidation and amalga- mation of the compound basis of ammonia is mentioned, which these ingenious gentlemen regard as a strict proof of the idea I had formed of its being an oxide with a binary basis. Mercury, negatively electrified in the Voltaic circuit, is placed in contact with solution of ammonia. Under this agency it gradually increases in volume, and, when ex- panded to four or five times its former dimensions, becomes a soft solid. And that this substance is composed of the deoxigenated compound basis of ammonia and mercury, they think is proved; 1. By the reproduction of quicksilver and ammo- nia, with the absorption of oxigen, when it is exposed to air; and secondly, by its forming ammonia in water, while hi- drogen is evolved, and the quicksilver gradually becomes free. An AMALGAM PRODUCED FROM AMMONIA. 55 An operation, in which hidrogen and nitrogen exhibit metallic properties, or in which a metallic substance is ap- parently composed from its elements, cannot fail to fix the attention of chemists: and the peculiar interest, which it offered in its relations to the general theory of electrochemi- cal science, induced me to examine the circumstances con- nected with it minutely and extensively. In repeating the process of the Swedish chemists, I The p™cel8 found, that to form an amalgam from fifty or sixty grains of mercury, in contact with saturated solution of ammonia, re- quired a considerable time, and that this amalgam greatly changed even in the short period required for removing it from the solution. -I was however able, in this mode of operating, to witness all the results they have stated, and I soon found simple and more easy means of producing the effect, and circumstances under which it could be more distinctly analysed. The experiments, which I have detailed in the Bakerian Ammonia pro- lecture for 1806, proved, that ammonia is disengaged from naSCem s\ate the ammoniacal salts at the negative surface in the Voltaic would be acted circuit; and I concluded, that, under this agency, it may Jj more rea* be acted on in what is called the nascent state, when it was reasonable to conclude it would be more readily deoxigen- ated and combined with quicksilver. On this view of- the subject, T made a cavity in a piece of 50 grs. of mer- muriate of ammonia; into this a globule of mercury, acavSy^n mi£ weighing about fifty grains, was introduced. The muriate riate of ammo- was slightly moistened, so as to be rendered a conductor, "l *and electri" and placed on a plate of platina, which was made positive in the circuit of the large battery. The quicksilver was made negative by means of a platina wire. The action of the quicksilver on the salt was immediate ; a strong effer- vescence with much heat took place. The globule in a few Amalgam pro- minutes had enlarged to five times its former dimensions, duced- and had the appearance of an amalgam of zinc; and me- tallic crystallizations shot from it, as a centre, round the body of the salt. They had an arborescent appearance, of- ten became coloured at their points of contact with the mu- riate ; and when the connection was broken, rapidly disap- peared, S6 AMALGAM PRODUCED FROM AMMONIA. peared, emitting arumoniacal fumes, and reproducing quick- silver. Carbonate of When a piece of moistened carbonate of ammonia was ammonia pro- use(j tne appearances were the same, and the amalgam was duced a similar . rr B . amalgam, formed with equal rapidity. In this process of deoxidation, when the battery was in powerful action, a black matter •and some car- formed in the cavity, which there is every reason to believe was carbonaceous matter from the decomposition of the carbonic acid of the carbonate*. Potassium so- The strong attraction of potassium, sodium, and the me- dium, &c. em- tals of the alkaline earths for oxigen, induced me to exa- oxWateammo- mme wnetner their deoxidating powers could not be made nia without to produce the effect of the amalgamation of ammonia, in- 00 ICI y* dependently of the agency of electricity; and the result Was very satisfactory. When mercury, united to a small quantity of potassium, sodium, barium, or calcium, was made to act upon moist- ened muriate of ammonia, the amalgam rapidly increased to six or seven times its volume, and the compound seemed to contain much more ammoniacal basis than that procured by electrical powers. The amalgam As in these cases, however, a portion of metal used for oo pure. ^e deoxidation always remained in union in the compound ; in describing the properties of the amalgam from ammonia, I shall speak only of that procured by electrical means. Its properties. The amalgam from ammonia, when formed at the tem- perature of 70° or 80, is a soft solid, of the consistence of butter: at the freezing temperature it becomes firmer, and a crystallized mass, in which small facets appear, but having no perfectly defined formf. Its specific gravity is below 3, water being one. When thrown into water it produces a quantity of hi- ♦ The black matter which separates at the negative surface in the elec- trical experiments on the decomposition of potash or soda, and which some experimenters have found it difficult to account for, is I find car- bonaceous, and dependent upon the presence of carbonic acid in the al- kali. [See our Journal, vol. XIX, p. 156, and 307 ] •f- From the facet I suspect the form to be cubical. The amalgam of potassium crystallizes in cubes as beautiful, and in some cases as large, as those of bismuth. drogen, AMALGAM PRODUCED FROM AMMONIA. , '. ' $J, clrogen, equal to about half its bulk, and in consequence of this action the water becomes a weak solution of ammonia. When it is confined in a given portion of air, the air erir larges considerably in volume, aud the quicksilver reap- pears. Ammoniacal gas, equal to one and a half or one and three fifths of the volume of the amalgam is found to be produced, aud a quantity of oxigen equal to one seventh, or one eighth of the ammonia disappearsf. When thrown into muriatic acid gas, it instantly becomes coated with muriate of ammonia, and a small quantity of* hidrogen is disengaged. In sulphuric acid it becomes coated with sulphate of am- monia and sulphur. I attempted by a variety of modes to preserve this amal- The metal gam. I had hoped by submitting it to distillation out ofg^ffi^* the contact of air, or water, or bodies which couid furnish rate, oxigen, to be able to obtain the deoxigenated substance, which had been united to the quicksilver in a pure form ; but all the circumstances of the experiment opposed them- selves to such a result. It is well known to persons accustomed to barometrical experiments, that mercury, after being once moistened, re- tains water with great perseverance, and can only be freed from it by boiling ; and in the cases of the decomposition of ammonia, when a soft amalgam had been kept continu- ally moist, both internally and externally for some time, it could not be expected, that all the water adhering to it should be easily removed. I wiped the amalgam as carefully as possible with bibu~ lous paper; but even in this process a considerable portion of the ammonia was regenerated ; I attempted to free it from moisture by passing it through fine linen, but a complete decomposition was effected, and nothing was obtained but pure quicksilver, The whole quantity of the basis of ammonia combined in sixty grains of quicksilver, as is evident from the statements that have been made, does not exceed T^7 part of a grain, j This experiment confirms the opinions I have stated concerning the quantity of oxigen in ammonia ; but as water is j resent, as will be im- mediately shown, the data for proportions are not perfectly correct. and 58 The amalgam quickly de- composed. Distilled. Tlie triple amalgams may be pre- served some time. Heated oyer mercury. AMALGAM PRODUCED FROM AMMONIA. sod to supply oxigen to this scarcely ttjVjj- part of a grain of water would be required, which is a quantity hardly appre- ciable, and which merely breathing upon the amalgam would be almost sufficient to communicate. Hence, when an amalgam, which had been wiped by means of bibulous paper, was introduced into naphtha, it decomposed almost as rapidly as in the air, producingammo- nia and hidrogen. In oils it evolved hidrogen, and generated ammoniacal soap ; and when it was introduced into a glass tube, closed by a cork, gas was rapidly formed, and the mercury re- mained free; and this gas, when examined, was found to consist of from about two thirds to three fourths ammonia, and the remainder hidrogen*. That more moisture sometimes existed attached to the amalgam, when wiped as dry as possible by bibulous paper, than was sufficient for the effect of decomposition, I soon found by an experiment of distillation. About a quarter of a cubic inch of an amalgam nearly- solid was wiped very dry, and introduced into a small tube : in this tube it was heated till the gaseous matter had expel- led the quicksilver ; the tube was then closed, and suffered to cool, when moisture, which proved to be a saturated so- lution of ammonia, had precipitated upon it. I have mentioned, that the amalgams obtained from am- monia by means of the metals of the fixed alkalis or alka- line earths seemed to contain much more ammoniacal basis in combination than those procured by electricity: and when they are combined with the metals of the fixed alkalis or of the earths in any considerable quantities, they are much more permanent. Triple compounds of this kind, when carefully wiped, scarcely produce any ammonia under naphtha, or oil, and may be preserved for a considerable time in closed glass tubes, a little hidrogen being the only product evolved from them. I heated a triple amalgam obtained from ammonia by * In the experiment of the action of the amalgam upon air, the oxi- gen is probably absorbed by nascent hidrogen, and reproduces water, which is dissolved by the ammonia. potassium AMALGAM PRODJCED FROM AMMONIA. $g potassium, and which had been wiped by bibulous paper, in a dry plate-glass tube over mercury ; a considerable eleva- tion of temperature was required before any gaseous mat- ter was emitted, but the heat was raised till gas was rapidly formed, and the whole of the amalgam expelled from the tube : in cooling, the mercury rose very quickly in it, so that a great part of the gaseous matter had been either mer- cury, or water, in vapour, or something which the mercury had absorbed in cooling. The small quantity, which was permanent, did not equal one half the volume of the amal- gam. On the idea that this gas might be a compound of hidro- The gas exa- gen and nitrogen in the state of deoxigenation, I mixed a mined, small quantity of oxigen gas with it, but no change of vo- lume took place; I then exposed it to naphtha, when one half of it was absorbed, which, by the effect the naphtha produced upon turmeric, must have been ammonia ; the re- maining gas analysed was found to consist of the oxigen that had been introduced, and of hidrogen and nitrogen to each other in the proportion of nearly four to one. At first I was perplexed by this result, which seemed to Here ammonia prove the production of ammonia, independent of the pre- apparently sence of any substance, which could furnish oxigen to it, out oxigen. and to show that its amalgamation was merely owing to its being freed from water, and combined with hidrogen : but a satisfactory solution of the difficulty soon offered itself. Exposing the triple amalgam procured from ammonia by The difficulty potassium to a concentrated solution of ammonia, I found, solved- that it had very little action upon it, and introducing the amalgam moistened by it into a glass tube, it had nearly the same permanency as the amalgam which had been wiped before it was introduced, a little hidrogen only being evolved ; but on heating the tube gaseous matter was rapidly gene- rated, which proved to consist of two thirds ammonia, and one third hidrogen. In the instance in which the amalgam had been wiped, a small quantity of solution of ammonia, and perhaps of potash, must have adhered to it; and though the amalgam does not act upon this powerfully at common temperatures, yet when the water is raised in vapour, it tends to oxigenate both 60 AMALGAM PRODUCED FROM AMMONIA. both the basis of ammonia, and potassium, and hence hidro- gen is evolved, and volatile alkali produced* S^wo?*" I distilled an amalgam procured by potassium from am* naphtha. monia, in a tube filled with the vapour of naphtha, and hermetically sealed, in the same manner as in the experi-. ments for obtaining the metals of the earths, but in this thing con- case I procured ammonia, hidrogen, and nitrogen only, and focedbat Plire mercury; and the residuum was1 potassium, which mercury, acted powerfully on the glass tube. even when ^ another experiment of the same kind, I kept one part of cooled by ice. the tube cool by ice, at the same time the other part was strongly heated, but nothing condensible except mercury was produced, and the elastic products were the san>3 as in, the former instance, Ammonia in J endeavoured to procure an amalgam from ammonia, to would not ga* wnicn no moisture could be supposed to adhere, by heating amalgamate, an amalgam of potassium in arnmoniacal gas. The amal- gam'became covered with a film of potash, but it did not enlarge in its dimensions, and a considerable quantity of nonabsorbable gas, which was found to consist of five parts of hidrogen, and one of nitrogen, was produced. The amalgam after this operation did not emit ammonia by ex- posure to air, hence it seems probable, that for the deoxi- genation of ammonia, and the combination of its basis with mercury, the alkali must be in the nascent state, or at least in that condensed form in which it exists in arnmoniacal salts, or solutions. VI. Some Considerations of general Theory, connected with Vie Metallization of the Alkalis and the Earths, j»ro p«rties of The more the properties of the amalgam obtained from the amalgam ammonia are considered, the more extraordinary do they ap- from ammonia extraordinary, pear. Mercury by combination with about ttStb- Vart °? ita weight of new matter is rendered a solid, yet has its specific gravity diminished from 13*5 to less than 3, and it retains all its metallic characters; its colour, lustre, opacity, and conducting powers remaining unimpaired. It is scarcely possible to conceive, that a substance, which forms with mercury so perfect an amalgam, should not be metallic AMALGAM PRODUCED FROM AMMOfflA. (Jl metallic in its own nature*; and on this idea to assist the discussion concerning it, it may be conveniently termed ammonium. - But on what do the metallic properties of ammonium de- pend? Are hidrogen and nitrogen both metala in the aeriform Are hidrogen state, at the usual temperatures of the atmosphere, bodies metaisj of the same character as zinc and quicksilver would be in the heat of ignition ? Or are these gasses, in their common form, oxides, which or °xuJes? become metallized by deoxidation? Or are they simple bodies, not metallic in their own na- ?r s.,mpe J r » ... bodies com- ture, but capable of composing a metal in their deoxi gen** posing a metal! ated, and an alkali in their oxigenated state? These problems, the second of which was stated by Mr. Cavendish to me, and the last of which belongs to Mr. Ber- zelius, offer most important objects of investigation. I have made some experiments in relation to them, but SjJJlJjjJ- as yet unsuccessfully. I have heated the amalgam of potas* treated with »ium in contact with both hidrogen and nitrogen, but with- 1122™ n" out attaining their metallization ; but this fact cannot be considered as decisively for or against any one of these con- jectures. I mentioned in the Bakerian Lecture for 1807, that a modi-* Modification fication of a phlogistic chemical theory might be defended °istic ^eory. on the idea, that the metals and inflammable solids usually called simple, were compounds of the same matter as that existing in hidrogen, with peculiar unknown bases; and that the oxides, alkalis, and acids were compounds of the same ba9es with water : and that the phaenomena presented by the • The nature of the compounds of sulphur and phosphorus with mer- cury favours this opinion ; these inflammable bodies by combination im- pair its metallic properties : cinnabar is a nonconductor, and it would seem from Pelletier's experiments, Ann. de Chimie, vol. xiti, p. 125, that the phosphuret of mercury is not metallic in its characters j charcoal is ft conductor, and in plumbago carbon approaches very near to a metal in its characters, so that the metallic mture of st»el does not militate ggainst the reasoning in the text Th« only facts wv) ch 1 urn acquainted frith, that do militate against it, are th:; metallic characters of some of tke sulpuutets and phosphurets of the imp«rf«ct metals. \ \ metals 62 AMALOAM PRODUCED FROM AMMONI4 metals of the fixed alkalis might be explained on this hy- pothesis. Less distinct The same mode of reasoning may be applied to the factf fbanSihePre- °^ tne raetaUization of the earths and ammonia, and per- ceived thecy. haps with rather stronger evidences in its favour; but still it will be less distinct and simple, than the usually received theory of oxigenation, which I have applied to them. The general facts of the combustion, and of the action of these new combustible substances upon water, are cer- tainly most easily explained on the hypothesis of 'Lavoisier; and the only good arguments in favour of a common prin- ciple of inflammability flow from some of the novel analo- gies in electrochemical science* Isnothldrogen Assuming the existence of hidrogen in the amalgam of the common ammonium, its presence in one metallic compound evidently element of in- ( ' r. . , • • . , j • flammable leads to the suspicion or its combination in others* And in bodies? the electrical powers of the different species of matter there are circumstances, which extend the idea to combustible substances in general. Oxigen is the only body, which can be supposed to be elementary, attracted by the positive sur- face in the electrical circuit; and all compound bodies, the nature of which is known, that are attracted by this surface, contain a considerable proportion of oxigen* Hidrogen it the only matter attracted by the negative surface, which can be considered as acting the opposite part to oxigen ; may not then the different inflammable bodies, supposed to be simple, contain this as a common element? Alkalis earths, Should future experiments prove the truth of this hypo- and metallic thesis, still the alkalis, the earths, and. the metallic oxides to the same"8 w'^ belong to the same class of bodies. From platina to class of bodies, potassium there is a regular order of gradation as to their physical and chemical properties, and this would probably extend to ammonium, could it be obtained in the fixed form. Platina and gold in specific gravity, degree of oxidability, and other qualities differ more from arsenic, iron, and tin, than these last do from barium and strontium. The phaenomena of combustion of all the oxidable metals are precisely analogous. In the same manner as arsenic forms an acid by burning in air, potassium forms an alkali, and calcium an earth ; in a manner similar to that in which osmium AMALGAM PRODUCED FROM AMMONIA. 6$ osmium forms a volatile and acrid substance by the absorp- tion of oxigen, does the amalgam of ammonia produce the volatile alkali; and if we suppose that ammonia is metal- lized, by being combined with hidrogen, and freed from water, the same reasoning will likewise apply to the other metals, with this difference, that the adherence of their phlogiston' or hidrogen would be exactly in the inverse ratio of their attraction for oxigen. In platina* it would be combined with the greatest energy ; in ammonium with the least ; and if it be separable from any of the metals without the aid of a new combination, we may expect that this re- sult will be afforded by the most volatile and oxidable, such as arsenic, or the metals of the fixed alkalis, submitted to intense heat, under electrical polarities, and having the pres- sure of the atmosphere removed. Whatever new lights new discoveries may throw upon this We are it least subject, still the facts, that have been advanced, show, that onesteP ad- a step nearer at least has been attained towards the true knowledge of knowledge of the nature of the alkalis and the earthsf. the earths and * . alkalis. ■ Something * The common metallic oxides are lighter than their bases, but pot- Specific gravi- ash and soda are heavier ; this fact may be explained on either theory ; ^es of com- the density of a compound will be proportional to the attraction of its ^UJ-1 ,f f^u parts. Platina, having a weak affinity for oxigen, cannot be supposed to attraction of condense it in the same degree as potassium does j or if platina and potas- their parts. g'uim be both compounds of hidrogen, the hidrogen must be attracted in platina with an energy infinitely greater than in potassium. Sulphuric acid is lighter than sulphur; but phosphoric acid, where there is a stronger affinity, is heavier than phosphorus. The oxide of tin (wood tin) is very little inferior to tin in specific gravity. In this instance the metallic base is comparatively light, and the attraction for oxigen strong; and in a case when the metal is much lighter and the attraction for oxi- gen stronger, it might be expected a priori, that the oxide would be hea- vier than the base. f Since the facts in this paper were communicated to the Royal So- Potassium ciety, I have seen an account of some very curious experiments of supposed to Messrs. Gay Lussac and Thenard, (in Number 148 of the Moniteur, for beacompound 1808, which I have just received,) from one of which they have con- • ' eluded, " that potassium may be a compound of hidrogen and potash." These gentlemen are said to have heated potassium in ammonia, and found, that the ammonia was absorbed, and that hidrogen gas equal to two thirds of it* volume appeared, and that the potassium by this pro- 64tS AMALGAM PRODUCED FROM AMMONIA. The tnflam- Something lias been separated from them which adds to their weight; and whether it be considered as oxigen, or as water .cess had become of a grayish-green colour. By hedltng this grayish- .green substance considerably, two fifths of the ammonia were again emitted, with a quantity of hidrogen and nitrogen corresponding to one fifth more; and by adding water to the mixture, and heating it very ftrongly again, they obtained the remainder of the ammonia, and nothing but potash was left. But the sup- In these complex processes, the phenomena may be as easily ex* position gratu- piained on the idea of potassium being a simple, as that of its being a compound substance; nor when the facts that have been stated in this paper, and those about to be stated, are considered, can the view of these distinguished chemists, as detailed in the notice referred to, be at all ad- mitted. Potash, as I have found by numerous experiments, has no affinity for ammonia, for it does not absorb it when heated in it ; it is not therefore, allowing their theory, possible to conceive, that a substance having no attraction for potash should repel from it a substance which is intimately combined with it, and which can be separated in no other way. The pheno- A part of the hidrogen evolved in their experiment may be furnished mena account- t,v water contained in the ammonia; but it is scarcely possible, that the j whole of it can be derived from this source, for on such an idea the am- monia must contain more than half its weight of water. There is how- ever no evidence, that the whole of the hidrogen may not be furnished by the decomposition of the volatile alkali itself. Potassium in its first degree of oxigenation may have an affinity for nitrogen, or potassium may expel a portion of hidrogen at the moment of its combination with ammonium; and as the whole of the ammonia cannot be regenerated with- tut the presence of water, hidrogen and a little oxigen may be furnished to the remaining elements of the ammonia from the water, and oxigen ta the potassium. Even before the conclusion was formed, that a metallic substance is decomposed in this experiment, it should have been proved, that the ni. trogen had not been altered. Potash cannot That mere potash combined with hidrogen cannot form potassium, is form potassium I think shown by an experiment, which I tried, in consequence of the by com ma- important fact, lately ascertained by Messrs. Gay Lussac and Thenard, droeen. °f the deoxidation of potash by iron: Experiment. ^n ounce °f potash was kept in ignition for some time in an iron tube, ground into a gun barrel in which one ounce and a half of iron turnings were ignited to whiteaess ; a communication was opened, by withdrawing a wire which closed the tube containing the potash, between that alkali and the metal. As the potash came into contact with the iron, gaseous matter was de- veloped, which was received in a proper apparatus 5 and though some of it AMALGAM PRODUCED FROM AMMONIA. 6$ water, the inflammable body is less compounded, than the Iesscom- inflammable substance resulting from its combustion. poun e an Other it was lost by passing through the potash into the atmosphere, yet neatly half a cubic foot was preserved, which proved to be hidrogen. In the tube was found two products, one in the quantity of a few grains, con- taining potassium, combined with a small quantity of iron, and which had sublimated in the operation, and the other a fixed white metallic substance, which consisted of an alloy of iron and potas&ium. The first of these substances burnt when thrown upon water j and in its other characters resembled pure potassium, except that its specific gravity was greater, its colour less brilliant, and when it tarnished in the atmosphere, it became of a much deeper colour than pure potassium. Now potash that has been ignited is the purest form known of this »r water Dre. alkali j but on Messrs. Gay Lussac's and Thenard's theory, this potash gent to have must contain water, not only sufficient to furnish hidrogen to metallize furnished hi- the alkali, but likewise the quantity disengaged : dry potash then, as it <*rogen, ♦s procured in our experiments, must on this theory be a compound, con- taining a considerable quantity of matter which can furnish hidrogen ; and what would be its form or properties if deprived of this matter we are wholly unable to judge, which brings this question to the general question discussed in the text. Potassium I find may be produced readily from dry ignited potash in anenic, yet from the experiments of these gentlemen it appears that potassium separates arsenic from ar- leniated hidrogen; and hidrogen, which is supposed by them to exist in both compounds, can have no affinity for hidrogen, nor can hidrogen in one form be supposed capable of separating arsenic from hidrogen in an- other form. Could not the experiment of Messrs. Gay Lussac and Thenard, be ex- plained, except on the supposition of the hidrogen being derived from the potassium, it -would be a distinct fact in favour of the revival Of the theory of phlogiston. It would not prove, however, that potassium is composed of hidrogen and potash, but that it is composed of hidrogen %nd an unknown basis > and that, potash is this basis united to water. * Phil. Trans. 1807, Part I, p. 23, or pur Journal, vol XIX, p. 3S8. The amalgam obtained from ammonia ofFers difficulties to both the phlogistic and antiphlogistic hypotheses. If we assume the phlogistic hypothesis, then we must assume, that nitrogen, by combining with one fourth of its weight of hidrogen can form an alkali, and by combining with one twelfth more can become metallic. If we reason on the anti- phlogistic hypothesis, we mustasseit, that, though nitrogen has a weaker affinity for oxigen than hidrogen. yet a compound of hidrogen and ni- trogen is capable of decomposing water. The first assumption is however by far the most contradictory to the •rder of common chemical facts; the last, though it cannot be wholly lemoved AMALGAM PRODUCED FROM AMMONIA. ()J I venture to hint at these notions: but I do not attach Theory of cha- in u;h importance to them; the age of chemistry is not yet "JJJJJJJ0* yet sufficiently mature for such discussions ; the more subtile -powers of matter are but just beginning to be considered; and all general views concerning them must as yet rest upon feeble and imperfect foundations. Whatever be the fate of the speculative part of the in- quiry, the facts however will, I hope, admit of many appli- cations, and explain some phenomena in nature. The metals of the Earth cannot exist at the surface of the phenomena of globe ; but it is very possible, that they may form a part of volcanoes, the interior; and such an assumption would offer a theory for the phaenomena of volcanoes, the formation of lavas, and the excitement and effects of subterraneous heat*, and would probably lead to a general hypothesis in geology. The removed, is yet lessened by analogies. Thus alloys in general, and in- flammable compounds, are more oxidable than the simple substances that compose them. Sulphuret of iron at common temperatures de- composes water with facility ; whereas sulphur under the same circum- stances has no action on water, and iron a very small one. The com- pound of phosphorus and hidiogen is more inflammable than either of its constituents. Should a new theory of the dependence of the chemical forms of Theory of the matter upon electrical powers be established, the facts belonging to am- dependence of monium would admit of a more easy solution. Ammonium might be chemical forms supposed to be a simple body, which, by combining with different quan- °n e e^ aca ties of water, and in different states of electricity, formed nitrogen, am- monia, atmospherical air, nitrous oxide, nitrous gas, and nitric acid. Water, on this idea, must be supposed a constituent part of all the different gasses ; but its electricities in oxigen aud hidrogen would pro- bably be the very reverse of what they have been supposed by Mr. Rit- ter, and some ingenious English inquirers. Water positively electrified would be hidrogen, water negatively elec- trified, oxigen j and as in the physical experiments of temperature, ice, added to certain quantities of steam, by an equilibrium of heat produces water, so in the chemical experiment of the generation of wafer the positive and negative electricity of oxigen and hidrogen in certain pro- portions would annihilate each other, and water alone be the result. At all events ammonium, whether simple or compound, must be considered as owing its attraction for oxigen to its highly positive electrical state, which is shown by its powerful determination to the negatiTe surface in the Voltaic circuit. • Let it be assumed, the metals of the earths and alkalis, in alloy with F » commo ft 68 DISTRIBUTION OF FOSSIL COIL. Meteors. The luminous appearance of those meteors connected with the fall of stones is one of the extraordinary circum- stances of these wonderful phenomena. This effect may be accounted for, by supposing, that the substances, which fall, come into our atmosphere in a metallic state; and that the earths they principally consist of are a result of combus- tion ; but this idea has not the slightest connexion with their origin or cause. dtc. X. On the supposed universal Distribution of Fossil Coal, in Reply to Mr. B. Cook, Vol. XXI, page 292; and on the Nature and Situations of the extraneous Fossil (Belemnite) analysed by Mr, J. Acton, at page 305, under the De- nomination of a" Crystal" called a Thunder-pick, In a Letter from Mr. John Farey. To Mr. NICHOLSON. SIR, Assertion, that A"T *s sincerely to be regretted, when practical and highly c«al may be useful papers, like that of your correspondent Mr. B. Cook most all parts on ^e advantage of gas lights, in your number for Dec, ef this country, contain any assertions or speculations, which, being foreign to the profession or pursuits of the writer, are liable to mix errour with so much of practical and useful truth. I was led to these reflections by the following remarks of your correspondent at page 292. *« This country produces a vast " quantity of coal, in almost every part where it is properly *' sought for ;" if gas lights were generally introduced, it might raise the price of coals, " but it certainly would be a " stimulus to men of landed property to seek for it, where common metals, exibt in large quantities beneath the surface, then their accidental exposure to the action of air and water must produce the effect of subterranean fire, and a product of earthy and stony matter analogous to laras. « "to DISTRIBUTION OF FOSSIL COAL. 6Q u to the present it has been supposed a stranger: it would *' therefore, if the demand was so much greater, be found, *' I am sure, in greater quantities than at present, as miners " would be induced to seek it every where." A greater or more common mistake is not often com- a mistake of se< mitted, than this which Mr. Cook has fallen into, in sup- lious moment, posing, that coals might be any where met with, if sought for; an errour which has occasioned the useless expenditure of hundreds and sometimes of thousands of pounds, in nu- merous instances, as some in the vicinity of Boxhill in Sus- sex can testify, ou recent experience. A district passing from Somersetshire, through Gloucestershire, Warwick- Only coal dis- shire, Leicestershire, Nottinghamshire, Derbyshire, York- tricts* shire, and Durham ; and some local districts to the west- ward and northward of this line, contain numerous and valuable seams or strata of coal; but to the eastward or southward of this line, no coal ever has or probably ever will be found, at practicable mining depths, owing to these south-eastern districts being universally covered by great thickness of upper strata to any which contain coal*9 and which upper strata seem to cover many of the intervening §paces in the north-western districts of Britain ; while in others of these spaces, the coals and their accompanying strata seem wanting, and lower strata, from beneath the coal measures, lie exposed. The substance called a thunder-pick, the analysis of which The thunder- is given by Mr. J. Acton at page 305, is not " a crystal," (as ^ notac,7- Dr. Woodward supposed) but the exuvia of an animal now unknown, called a belemnite; which extraneous fossils are frequently found among alluvial matter, on the surface of ploughed lands, mixed with the ruins of the stratum from which they have been dislodged. A stratum in the clay under the Woburn sand produces belemnites in great numbers throughout its whole course, so does a stratum in the great Bath freestone range of hills (see Walcot's Petri- * Biluminated wood lodged in white clay, such as occurs at Borry Tracey in Devonshire, has often been confounded by sanguine specula* tors with fossil coal, to the cruel disappointment of themselves and others. factions 70 BRITISH COFFEE. factions found near Bath, page 34), another in the chalk strata, and perhaps others in the British series of strata. I am, Sir, Your humble servant, JOHN FAREY. Upper Crown Street, Westminster. XI. Account of a British Vegetable Product, that may be Sub- stituted for Coffee. In a Letter from Mr. William Skrimshire, Jim. To Mr. NICHOLSON. a SIR, British substi- J[n the first week of October last, I discovered a vegetable ' product of British growth, which by particular manage- ment may prove an excellent substitute for foreign coffee, and immediately made it a subject of communication to the Scientific Society in this place. But as I cannot learn, that the substance in question has ever been applied to a similar purpose by any other person, I conceive the circumstance of sufficient importance, to claim the public attention, and should you coincide with me in this opinion, I shall be happy to have it form an article in your valuable miscel- lany. Yours, &c. W. SKRIMSHIRE, Jun. British Coffee, Common yety The iris pseudacorus, flower de luce, or common yellow water flag, is a plant which grows in great abundance in some marshes, and by the sides of rivers and ditches. The seeds The germen, or seed pod, which is here provincially and vulgarly called old sows, is well stocked with seeds covered with chesnut coloured husks. These may be readily thrashed from BRITISH COFFEE. 71 from the pods when they are ripe/ and, if deposited in a dry place, will keep well for a long time. This beautiful and ornamental plant is so productive of Tery plentiful. feeds, that I gathered more than a bushel of them in the space of a few yards, by the side of an old river, in this neighbourhood. The seeds of this plant, being roasted in the ssme man- When roasted ner as coffee is treated, very much resemble it in colour and rf01C°0eanlUi,e" flavour; but have something more of a saccharine odour ap- other substi* proaching to that of the extract of liquorice. However, tute' when carefully prepared, they possess much more of the aroma of coffee than is to be found in any, of the leguminous and gramineous seeds, that have been treated in the same manner. The government duty Upon coffee having been lately taken off, this new product cannot at present be brought to market as a lucrative article of commerce; yet I trust these observations may prove of considerable advantage to those persons, in whose vicinity the iris pseudacorus abounds. Some persons may perhaps object to the use of these seeds Not cathartic* as here recommended, on account of the yellow water flag being a medical plant, possessing so violent a purgative ef- fect upon the human frame, as to render its administration extremely unsafe. I readily grant, that the fresh root is a very drastic cathartic; but I assert, that the other parts of the plant do not possess the same virtues as the root ; and that even the root itself, when perfectly dried, is one of the Even the root, most powerful astringents, that this country produces, and wv^n *d» att is probably one of the most effectual remedies of this class, that we can employ to remove a diarrhoea, or too great a laxity of the bowels. Besides, I can speak positively from Used by the my own experience, that the coffee from the seeds of the author, yellow water flag is very wholesome and nutritious, in the proportion of half an ounce, or an ounce, to a pint of boiling water. And as far as a few experiments enable me to form an Has the che- opinion, I expect, that this product will be found to possess "llcal Pr0Per- most of the chemical as well as physical properties of the foreign coffee. The phenomena which occur in roasting the seeds are 72 BRITISH COFFEE. The seeds de •cribed. Iffects of roasting. 80 very similar to what take place in foreign coffee during the same process, that I shall presently relate them. The seeds of the iris pseudacorus when ripe, fresh ga- thered, and freed from the husks, are of a dirty brown cor lour, semitransparent, and tough like horn. They have, if I may be allowed the expression, a leguminous taste. Their form is various, some are circular and thin, others wedge shaped, while others again are conical* resembling minute bulbous roots. They are between three and four lines in breadth, never more than four, and they are seldom more than two lines in thickness, but generally much thinner. Beside the arillus, which merely covers the crown of the seed, it is closely enveloped by a very thin brown epidermis, which firmly adheres to the rugous surface of the seed, givr ing it the appearance of very fine shagreen. When this covering is removed, the seed itself is of a yellowish colour. Under the microscope this epidermis appears to consist of a congeries of papillae distilling an oil from the surface of the seed underneath *. When the seeds are exposed to heat upon an iron plate, in order to roast them, they at first crackle and are covered with minute blisters, they change to a reddish brown colour, and are rendered opake ; they next become dark brown, and almost black, by the carbonization of the epidermis; they now sweat, or appear oily, emit a dense smoke, and acquire the aromp of coffee. If they be taken from the fire at this stage of the process, and wrapped in unsized paper, it ab- sorbs the oil, and different parts of it thereby become trans- parent. In this state the epidermis, though carbonized, does not easily separate from the seed, but adheres to its oleaginous surface, giving it a very dirty appearance. But if rubbed in a cotton or woollen cloth, or tossed to and fro in a bag but partly filled with them, they may be freed from this carbonaceous matter, and will thus receive a polish that will enable them to bear handling without staining the fin- gers. • The arillus, the epidermis, and even very thin cuttings of the seed itself are exceeding beautiful microscopic objects. If BRITISH COFFEE. 73 IF the process of roasting be continued longer, the smoke Over-roasting, increases in quantity and density, acquiring a very pene- trating empyreumatic odour, the seeds become black from carbonization, and the aroma is entirely destroyed. The two great inconveniences in performing this opera- Precautions to tion with the greatest success are, 1st, the shape of the seeds, which occasions an inequality in the roasting, unless they be continually stirred during the process : 2dly, the tough consistence of the seeds, which renders it necessary to conduct the operation very slowly, for if the fire be too violent, the oil will be burnt and communicate a nauseous flavour to the coffee ; and if the seeds be not sufficiently dried and hardened by the continuance of the heat, they will remain too tough for the mill to be able to grind them. In short, the whole art of roasting them consists in being able to continue the heat long enough to render the seeds of a dark brown colour, perfectly opake, and sufficiently brittle to be readily ground by the mill, without allowing it to be so fierce as to carbonize the oil, which exudes from them. These very directions are as precisely applicable, and as These precau. necessary to be attended to, in roasting foreign coffee, as in ^?J£ coffeeST* preparing the seeds of the iris pseudacorus. I have preserved the aroma of this British coffee in the greatest perfection, by roasting the seeds in the husks; and could a method be contrived for separating the roasted seeds from the carbonized husks, which may easily be done, I have no doubt but this would be by far the best method of con- ducting the process. P. S. 1 hope the idea of presenting the public with a general Index to the Philosophical Journal is not wholly given up. The work itself is now so considerable a depo- sitory of knowledge and multifarious information, that it is become a work of daily reference, and the public have a right to expect a general index. So far from the sale of the work being diminished by such a measure, I should think it would be increased by the adoption of a fresh series. W. S. XIL 74 SUBSTITUTE FOR EMERY, XII. Account of some ferruginous Rocks serving as Substitutes for Emery, By Mr. Blavier, Mine Engineer *. Slf c*sr ™ ATURALISTS are agreed in confining the name of dered an essen- emery to a rock containing corundum ; but if we were to tial part of comprise under this general term every matter capable like the true emery of giving the highest polish and lustre to metals, marbles, granites, and other substances necessary or An iron ore useful in the arts, we might admit into this class the mica» tm6,!*, 1 !~ ceous iron ore, which occurs in the hollows and on the sura* same purposes. " mit of the granitic table-land between the left bank of the Aveyron and the Viaur. Where found. This substance is found chiefly, and in the greatest abun* dance, at the bottom of the mountain of Rodez. Its colour is sometimes gray, at others of a deeper or lighter red, but in either case its fracture is steel-grained. It occurs thus on the banks of the brook of Briane, and at a little distance from Boutonnet, in the commune and arrondissement of Rodez. These ferruginous rocks exist in the hollows in rounded nodules, and in masses, the weight of which some- times amounts to upward of 5 myriagr. [about 1 cwt.]. May we not suppose, that these nodules are nothing but fragments separated from the veins, that appear of different thicknesses through the quartzose schists deeply tinged with iron, that form the higher hills? This situation is at present well known along the Briane, and it agrees perfectly with the different points, where this mineral has been turned up by the plough. Thus similar blocks are found on the sum- mit of the table-land, particularly in the domain of Puech, and at the side of the monastery, directly south and oppo- site to the mountain of Rodez. The same ferruginous rock exists in separate and more or less bulky fragments on the back of the hill, that forms the separation between the cal- careous band of St. Radegonda and the schistous ground that continues parallel with the left bank of the Aveyron as far as the granitic hill of Levezon. On descending the * Journal des Mines, No. ill, p. »oi, north-east SUBSTITUTE FOR EMERY. 75 north-east declivities of this hill, toward the coalpit of Sen- sac, we meet with this ferruginous ore in the greatest abun- dance, and always with the reddish colour of wine lees. , Farther researches will lead us to the discovery of its bed, the correspondence of which with the mine of Boutonnet will easily be established, since the narrow flat of Saint Radegonda is the only space that separates them. Be this as it may, I can aver, that all the schistous land Begun to be abounds with this kind of ore; and the working it has al- ready engaged the attention of one of the proprietors of Boutonnet, who has solicited from government a permission to search for this substance, in order to its being used in the arts as a cheap substitute for emery. | A stamping mill with three pestles and a few troughf would be sufficient for the establishment of a manufactory, the produce of which would be the more important, because, after having extracted the coarser emery, which constitutes the principal consumption of workers in marble and some other artists, the last deposit of the washing would yield a substance capable of supplying the place of English rouge A substitute for the last polish given to metals and even glass. For this ^kewise fc>r nothing more is necessary, than to repeat the washings, till it is brought to a sufficient degree of fineness. The situation of Rodez is very favourable for such an un- dertaking ; since the manufactories of arms at Tulles and Saint Etienne would occasiou a considerable demand for the article ; and on the other hand the statuaries of Toulouse and some other neighbouring places would find great advan- tage in using it. Lastly, it appears, that for polishing look- Might be use* ing glasses it might be substituted instead of emery of the *°.r PolishixIS first and second quality ; and I doubt not but with a little practice and patience the workmen may use it all through the process, when they have learnt to prepare it in a proper manner for grinding and polishing at the same time. The artificial emeries however, which we now know how to com- pose, prevent our being any longer embarrassed with the di£. ficulty of procuring native emery ; and if I recommend the establishment here mentioned, it is particularly on account of the cheapness at which its produce may be obtained, es- pecially by the neighbouring manufacturers. XIII. 76 ON THE ANTHOPHYLLITE. XIII. On the Anthophyllite ; by J. C. Delametherie*. Anthophyllite Jl HE anthophyllite described by Schumacher is found at wa " Kongsberg in Norway. It has the appearance of asbestoid, or strahlstein. I have an asbestoid from the Tyrol, that re- sembles it greatly. Its crystals are prisms, the former of which has not yet been determined. Its colour is a brown green inclining a little to violet. It6 specific gravity, aor cording to Karsten, is 3*156f. Dr. John of Berlin, has analysed this substance, and ob- tained from a hundred parts, Its component Silex 6<2'66 fart*. Alumine 13*33 Oxide of iron • ■ » • • 12 Magnesia 4 Lime 3*33 Oxide of magnesia • * 3*25 98*57 Loss i-43 100. This analysis evidently approaches near that of the as- bestoid ; accordingly, I have placed it next the asbestoid in my classification of minerals. SCIENTIFIC NEWS. Wemerian Natural History Society, Coal-formation 2^5™ 1\T the meeting of the society on Saturday the 19th of November, Mr. Mackenzie junior, of Applecross, read a short account of the coal-formation in the vicinity of Dur- ham. From the precise and accurate description commu- nicated by this gentleman, the rocks appear to belong to the oldest coal-formation of Werner. During the course of hi» observations, he explained what is called the creep by min- ers, and exhibited specimens of the different rocks, and a section of the coal-mine of Kipier, in which both the miners' appellations and the scientific names of the different strata were inserted. • Journal de Physique, vol. LXIV, p. S5/>. + Haiiy gives its spec. grav. 3-292, and suspect* it to bt merely a va- riety of the Labradot hornblende. T. At SCIENTIFIC NEWS. ff At the same meeting, Dr. Ogilby of Dublin read the con- Mineralogy of tinuation of his description of East Lothian, under the ti- East Lothian* tie of Observations on Veins of the newest Floetz-trap of East Lothian. After some preliminary observations on the general geognostic relations of the rocks of East Lothian, and of the precipitation of feldspar in its different states of fineness, from earthy to glassy feldspar, he proceeded to de- scribe the different veins he had an opportunity of examin- ing in this tract of country. These veins he considered as of three different periods of formation; viz. 1. Veins de- rived from partial formations subsequent to the floetz-trap, which however are not of frequent occurrence ; 2. Veins of the different rocks of the formation penetrating the older beds : and, 3. Those of contemporaneous origin. He nyext enumerated and described, after the manner of Werner^ the following veins,—- greenstone, jasper, quartz, heavy-spar, and calc-spar; and concluded with several interesting general remarks. At this meeting, also, Mr. P. Neill read some observations Great ce*. on the great sea snake of the Northern ocean. He enu- 8n*ke. * merated and read extracts from the different authors, who have mentioned it,— Ramus, Egede, and Pontoppidan. He remarked, that it was placed, by the latter author, between the mermaid and the kraken, in a chapter which treats on sea monsters; and that, standing in such suspicious company, it had been rejected by naturalists in general as a fabulous creature. He stated however, that, within these few weeks, Onelatelr a vast marine animal, shaped like a snake, and not described driven ashore in the works of systematic naturalists, had been cast ashore * r nejr' in Orkney. This curious animal, it appears, was stranded in Rothesholm Bay, in the island of Stronsa. Malcolm Laing, Esq., M.P., being in Orkney at the time, communicated the circumstance to his brother Gilbert Laing, Esq., advo- cate, Edinburgh, on whose property the animal had been stranded, Through this authentic channel Mr. Neill re- ceived his information. The creature was dead when it came ashore, and the tail seemed to have been injured and broken by dashing against the rocks. The body measured fifty-five feet in length, and the circumference of the thickest part was equal to the girth of an Orkney poney. The J-g SCIENTIFIC NEWS. The head was not larger than that of a seal, and was fur- nished with two blowholes. From the back, a number of filaments (resembling in texture the substance called silk- worm gut, or Indian sea grass) hung down like a mane. On each side of the body were three large fins, shaped like paws, and jointed. Before measures could be taken for se- curing this rare animal for the inspection of naturalists, a violent tempest unfortunately occurred, and beat the carGase to pieces. Some fragments however have been collected by Mr. Malcolm Laing, and are to be deposited in the Museum of the University of Edinburgh. Mr. Neill concluded with remarking, that no doubt could be entertained, that this was the kind of animal which had served as the proto- type of all the wonderful sea-snakes, whose appearance is on record; and that although the unfortunate destruction of the specimen by the storm may probably render it im- possible to form a correct generic character on Linnean principles, yet a place (if it should be in an appendix,) could no longer be refused by the most scrupulous natur- alists to the serpens marinus magnus of the bishop of Ber- gen. Sea unlcom. At the meeting of this Society the 10th of December, the Secretary read a communication from the Rev. John Fle- ming of Bressay, describing a narwhal, or sea-unicorn, of the sort denominated le ndrwal microcephale, by la Ce- p&de, which had been lately cast ashore alive at Weisdale Sound in Zetland. The description was accompanied with a correct drawing of the animal, which is to be engraved. Mineralogy of At the same meeting, Dr. Ogilby of Dublin read a paper Fassnet. oq ^g transition greenstone of Fassnet in East Lothian, which beside much valuable mineralogical information, con- tained a satisfactory answer to the query proposed some time ago by Professor Jameson in regard to the goegnostic rela- tions of the rocks of this tract of country. The descrip- tions of the individual rocks, and their general and particu- lar geognostic relations, were detailed with ability; and the interest of the whole was increased by acute observations on the mode of examining and discriminating rocks,— a subject of high value, particularly to those who may be employed in examining the mineralogy of a country. The SCIENTIFIC NEWS. 79 The following gentlemen have been elected office-bearers Officers for of this society for 180* :— l809* President. R. Jameson, Esq., Prof. Nat. Hist. Edin. Vice Presidents. Dr. Wright, Dr. Macknight, Dr. Bar- clay, and Dr. Thomson. Of the Council. Gen. Dirom , Col. Fullerton , C . S. Men- teith, Esq., Dr. Home, Dr. Yule, James Russell, Esq., C Anderson, Esq., and C. Stewart Esq. Treasurer. P. Walker, Esq. Secretary. P. Neill, Esq. Mr. CARMICHAEL, of Dublin, has in the press a se- Carmichael ©a cond edition of his Essay on the Effects of Carbonate and the effect of other Preparations of Iron upon Cancer, with an Inquiry onlcan°ei! ^d into the Nature of that Disease. This edition, we under- the uses of - stand, is so much enlarged and improved, that it may al- PS^^i^ most be considered as a new work. Among the additions are a great number of highly interesting cases; a disquisi- tion on the uses of the oxide of iron in the blood ; and re* marks on such diseases, as depend on its excess or deficiency, or in any way bear a relation to cancer ; with an attempt to answer the Queries of the Medical Society established in London for investigating the nature and cure of that corn- corn- plaint. ■""■ ^mmmm" Mr. George Singer, has by some recent arrangements Scientific in- considerably improved the original plan of the Scientific stitution. Institution, Prince' s-street, Cavendish square ; at which in future the public lectures are to be assisted by courses of private instruction, and conversations on the various subjects of philosophical inquiry; which are severally illustrated by an extensive and increasing collection of instruments. The attention of the pupils in the ensuing season will be principally directed to subjects of electrical and chemical research ; with particular reference to the developement and explanation of the new experiments. A sketch of the plan of this institution, and a prospectus of the lectures, is pre- paring ; and may be shortly obtained at the lecture room. London Hospital. Dr. Buxton's, Lectures on the theory and practice of Me- Medical J«o» dicine and on materia medica will be commenced about the tureg* 20th. January, 180Q. METEOROLOGICAL JOURNAL For DECEMBER 1808, Keptby ROBERT BANCKS,Mathematical Instrument Maker, in the Strand, Lundon. THERMOMETER. 1 BAROME- TER, WEA1 rHER. NOV. . « *j j 36 2§ 8 a> Day of < Cu .2° to 9 A. M. Night. Day. o> o> £ 26 50 52 54 50 29\98 Cloudy Rarn 27 50 42 54 34 29*50 Fair Ditto 28 35 36 53 34 29'8 I Ditto Faii- 29 36 41 47 40 2977 Rain Rain 30 42 41 46 37 29 16 Fair Fair DEC. . 1 40 43 47 42 29-36 Ditto* Ditto 2 41 43 47 41 29-17 Ditto Ditto 3 42 46 47 42 29-45 Ditto Ditto 4 41 40 48 36 30-02 Fog Ditto 5 40 48 49 48 30-27 Mist Cloudy 6 50 47 52 34 29-97 Fair Rain 7 35 39 42 32 29-89 Ditto Fair 8 34- 40 41 40 29*95 Ditto Ditto 9 41 39 44 33 29-86 Fog Ditto . 10 35 40 40 34 30-08 Cloudy Ditto 11 36 36 42 33 30-25 Fair Ditto 12 36 41 42 39 3025 Fog Cloudy 13 40 35 42 34 30-33 Rain Ditto 14 34 40 42 33 30-36 Cloudy Ditto 15 34 33 38 33 30-08 Ditto Fair' 16 33 33 35 30 30-07 Fair Ditto \7 32 26 34 22 29-82 Snowf Snow 18 26 30 32 28 29-62 FairJ * Fair 19 28 29 33 28 2965 Cloudy Snow 20 28 32 33 20 29-69 Fair Ditto 21 24 31 31 28 29-96 Snow Ditto 52 28 28 32 26 29-26 Ditto Ditto 23 27 32 32 27 2938 Ditto Ditto 24- 28 28 33 26 29-47 Cloudy Cloudy 25 29 30 30 24 29-56 Ditto Ditto 26 26 31 32 [ 30 29-49 Ditto Ditto • Heavy rain in the night. -f Stars brilliant at 6 P. M., snow at 9, high wind all night. X Snow at 5 P. M. Stars brilliant in the evening. At it appearance of change for thaw. A JOURNAL OF NATURAL PHILOSOPHY, CHEMISTRY, AND THE ARTS. FEBRUARY, 1809. ARTICLE L Description of a new Species of Whale, Delphinus melas. lt% a Letter from Thomas Stewart Traill, M. Z>. To Mr. NICHOLSON. Dear Sir, Description and correct drawing of an animal never New species of before figured by any naturalist cannot fail of being accept- whale, able to many of your numerous readers. Ninety-two whales of a new species were stranded in Scapay Bay, in Pomona, one of the Orkneys, a few days previous to the great storm in December, 1806. My friend James Watson, Esq. made the enclosed drawing (see Plate III) on the spot, the day after they were driven on shore. This animal very clearly belongs to the genus delphinus, Differs from of the class mammalia. The only hitherto described species the grampus, of that genus, which it at all resembles, is the delphinus orca, or grampus; but it is distinguished from the grampus by the shape of its snout, the shortness of its dorsal fin, the length and narrowness of its pectoral fins, the form and number of its teeth, and the colour of its belly and breast. Vol. XXII. No. 97— Feb. 1809. G It 82 NONDESCRIPT WHALE. Abundant It abounds in the sen around the Orkney and Shetland ney&Shet?arnd Isles* In Mr* Neill's interesting Tour through those is- islands. lands, we are informed, that 310 of this species were forced on shore in Shetland in 1805. From the imperfect account transmitted to him, this gentleman very properly conjectured them to be a new species. Description. Description. — The whole body almost is black, smooth, and shining like oiled silk. The back and sides are jetty black; the breast and belly of a somewhat lighter colour, The general length of the full grown ones is about twenty feet. The body is thick. The dorsal fin does not exceed two feet in length, and is rounded at the extremity. The pectoral fins are from six to eight feet in length, narrow, and tapering to their extremities. The head is obtuse ; the upper jaw projects several inches over the lower in a blunt process. It has a single spiracle. The full grown have twenty-two subconoid sharp teeth, a little hooked. Among those stranded in Scapay Bay were many young ones, which, as welf as the oldest, wanted teeth. The youngest measured about five feet in length, and were still sucklings. The females had two teats, larger than those of a cow, out of which the milk flowed when they were squeezed. Habits. These animals are gregarious, generally swimming in con- siderable numbers. They frequently enter the bays around the Orkney coast in quest of small fish, which seem to be their food. When one of them takes the ground, the rest surround, and endeavour to assist it: from this circumstance several of them are generally taken at once. I have fre- quently observed an animal, which I conjecture to be of this species, elevating its dorsal fin and a considerable part of its back above the waves, with a slow tumbling motion for many successive times. They are inoffensive, and rather timid. They are chased on shore not unfrequently by a fev* vawls. They seem generally to follow one as a leader with blind confidence. I once was in a boat when the attempt •was made to drive a shoal of them on shore ; but when they had approached very near the land, the foremost turned round with a sudden leap, and the whole rushed past us with great velocity, but carerully avoided the boat. They are ex-, trfcittely fat, and yield a considerable quantity of good oil. This APPARATUS FOR THE ANALYSIS OF GASSES. 83 This- new species may be denominated delphinus melas, Name and cha- on the sunie principle on which Gmelin gives the Beluga racter> the name of del ph. leucas. The following may serve as its character. Delphinus Melas. — Corpore crasso, nigro; pinna dorsali una brevi; pinnis pectoralibus longis, angustis; rostro obtuso ; maxitlo superiore proclinante ; dentibus acutis conoideis, parum incurvatis. THOMAS STEWART TRAILL. Liverpool, Dec. 17, 1808. II. Description of an Apparatus for the Analysis of the Com- pound Inflammable Gasses by slow Combustion ; with Ex- periments on the Gas from Coal, explaining its Applica- tion. By William Henry, M.D., Vice P res. of the Lit. and Phil. Society, and Physician to the Infirmary, at Manchester. Communicated by H. Davy, Esq., Sec. U.S.* JL HE aeriform compounds of hidrogen and carbon, which Compound in- were already entitled to accurate investigation, as objects of flammable gas- scientific research, have derived an additional claim to the !!!? ™*IU *ccu" raie exi mina~ attention of the chemist from their application to an im- tion, portant economical purpose, described in a late communi- cation to the Royal Society f. Yet there is, perhaps, no part of chemistry, the investigation of which is beset with but this liable greater difficulty, or with more numerous sources of errour ; to many er* insomuch, that the actual state of the science enables us to attain scarcely more than approximations to the truth, and degrees of probability of greater or less amount. It was the object of the experiments, which are described in the here attempted following pages, rather to remove some of the obstacles, toberemoyed which present themselves to a successful inquiry into the * Phil. Trans, for 1808, p. 282. f See Mr. Murdoch's paper, p. 124 5 or Journal, vol, XXI, p. 94. G 2 nature $4 APPARATUS FOR THE ANALYSIS OF GASSES. nature of these bodies, than to acquire such facts, as rosy enable the chemical philosopher to decide the controverted question respecting their composition. Results sufficiently multiplied and precise for this purpose would require a larger appropriation of time, than 1 have the prospect of Best method of being able to bestow ; and I can only on the present occasion proceeding. Q^er an exampJe 0f the method, in which it appears to me, that the analysis of this class of substances will be most suc- cessfully attempted. Vegetable sub- When a vegetable substance, composed (as may be is- stances. sumed to simplify the statement) of oxigen, hidrogen, and carbon, united in the form of a ternary compound, is sub- mitted to distillation, at a temperature not below that of ignition, the equilibrium of affinities, which constituted the triple combination, is destroyed; and the elements, com- posing it, are united in a new manner. Those, which are disposed to enter into permanently elastic combinations, cs- The carbon, cape in the state of gas. The carbon, uniting with oxigen, either composes carbonic acid gas, or, stopping short of that degree of oxigenation, which is essential to change it into The hidrogen. au acid, is converted into carbonic oxide. The hidrogen, combining with a portion of carbon, constitutes a binary compound of these two ingredients, forming either what has been called carburetted hidrogen gas, or supercarburetted hidrogen, better known by the appellation of olejiant gas* Toward the close of the process, a portion of simple hidro- gen gas is also mingled with the products. Perhaps in no The gasses al- instance is any One of the gasses, which have been enume- ways more or raj-e(] obtained perfectly pure, by the distillation of a vey-a- less mixed, W1 ■<. a •, . 8 table substance. The aeriform fluids, which are thus ge- nerated, are found to be possessed of almost every degree of specific gravity; and to yield, by combustion, extremely different results, according to the temperature at which they have been formed ; the stage of the process at which they have been separated; and other modifying circum- 6t their ele- stances. It becomes an interesting question, whether these edfeinSvl°rbusn* g*^8* so mucn diversified in their physical and chemical proportions, properties, are mixtures of a few binary compounds, with which chemists are already acquainted ; or whether, on the contrary, their elements are capable of uniting in indefinite proportions. APPARATUS FOR THE ANALYSIS OF GASSES. &5 proportions, and of composing ternary compounds of oxi- gen, hidrogen, and carbon, or varieties of oxicarburctted hidrogen. It would encroach too much on the time of the Royal Society, to enter upon this controversy. And, as neither opinion admits, at present, of demonstrative evi- dence, I may be permitted, in explaining the following ex- periments, to assume that theory, which appears to me most probable; viz. that the aeriform products of the distillation Most probably of vegetable substances are mixtures of carbonic acid, car- bonic oxide, defiant, carburetted hidrogen, and simple hidrogen gasses; or of two or more of these in various pro- portions. ■■ ■ » ■ • » ■ ■■ The analysis of these compound gasses has hitherto been Usual mode of attempted solely by their rapid combustion with oxigen gas, anal>'sls> in the following manner: a mixture of the inflammable gas with oxigen gas in known proportions is admitted into a Volta's eudiometer; inflamed over mercury by the electric spark ; and the diminution ascertained. To the remainder caustic potash or lime water is added, by which it sustains a second diminution of bulk; and the amount of this denotes the quantity of carbonic acid formed by the combustion. The quantity of nitrogen gas? in the oxigen employed, as well as in the residue left by potash, being determined by a fit eudiometrical test, it is easy to infer what quantity of oxigen has been absorbed by the detonation. And as it is proved, that oxigen gas sustains no change of bulk by con- version into carbonic acid, we may conclude, that, after deducting from the volume of oxigen gas expended that of the carbonic acid which has been formed, the remaining number shows how much oxigen has been employed in the saturation of hidrogen. If, for example, 100 measures of carburetted hidrogen consume 200 of oxigen gas, and give 100 of carbonic acid; it follows, that the carbonic acid holds in combination 100 measures of the oxigen gas consumed ; and that the remaining hundred have been applied to the saturation of hidrogen. In this estimate it is assumed, that One source cl the carbon has acquired, by combustion, the whole of the errour oxigen necessary for its acidification, and that no part of it existed previously in the state of carbonic oxide, a proposi- tion, in many cases, perhaps, very far from being consistent with 86* APPARATUS FOR THE ANALYSIS OF GASSES. may be de- w*,th the truth. This, however, admits of be'in*? decided by tected » an accurate comparison between the weight of the gasses consumed and that of the products. Gasses already jror ^e pUrp0Se Gf obtaining a general approximation to the nature of a combustible gas, it may be sufficient to exa- mine its coincidence with those, the properties of which have been already determined. The following table exhi- bits the results of the combustion of the few gasses, that appear entitled to be considered as distinct species. They are deduced from the experiments of Mr. Cruikshank and Mr. Dalton. Sp. Grav. (air =■= IOOO.) 100 measures, Kind of Gas. Take meas.of oxigen. Give carbo uicacicl Aiv dimi- nished by firing. Olefiant - Carbonized hidrogen, from ") stagnant water - - J Carbonic oxide - - - - Hidrogen gas - - - - 909 600 967 84 300 200 45 50 200 100 90 200 ■200 55 154 Inflammability of gasses pro- portional to the oxigen they consume. Results dis- trusted because they Taried consi- derably. The inflammability of the compound gasses, and their fitness for the purpose of affording light, are directly pro- portionate to the quantity of oxigen required for their satu- ration. The olefiant gas, therefore, burns with the greatest brilliancy ; carburetted hidrogen gas, though inferior, affords a. dense and compact flame ; but the carbonic oxide and hi- drogen gas are entirely unfit to be employed as the means of artificial illumination. In the execution of a series of experiments on the com- pound combustible gasses, which are described in the Uth volume of Mr. Nicholson's Philosophical Journal, I had reason to be dissatisfied with the above method of effecting their decomposition, and to distrust the results which were obtained. The products of the combustion of the same gas varied considerably in different experiments ; and, with re- spect to some, it was evident, that the full proportion of their carbonaceous ingredient was not oxigenised, in conse- quence of the precipitation of charcoal in the act of deto- nation. The quantities, also, that can be submitted in this way 2?ickoleor& Ftiks Journal FolJXJI.£l4- •/>■£/ r /////.<, APPARATUS FOR THE ANALYSTS OF GASSES. 87 way to experiment, are extremely minute; and the inflam- Experiments mation of highly combustible gasses is attended, as I have d.inger, more than once experienced, with considerable danger from the bursting of the glass tubes. It was desirable, therefore, to employ a process not liable to these objections; and after many alterations of the apparatus, contrived with this view, I at length fixed upon one, which I shall now proceed to describe. The principal parts of the apparatus, are two glass cylin- Apparatus ders, or air receivers*, bb and o o, PI. IV, of which the lhe anaiysis , larger one is intended to contain oxigen gas, and the smaller described. one, the inflammable gas submitted to experiment. They are connected by a bent glass tube s s, the diameter of which should not be less than TV of an inch, to the upper extremity of which is cemented an iron burner, t9 the ori- fice of which is about 7V of an inch, while to the lower end a socket is fixed, on which may be occasionally screwed the cock r. The receiver o o is contained in a larger glass jar n w, and is closed at the top by a brass cap p, and stop cock q. The oxigen gas receiver is also closed by a brass cap e and cock /, the lower orifice of which is tapped internally, for the purpose of receiving a small screw at the end of the copper wire g. This wire is in two parts, each of which screws into a movable socket, connecting the two ; and, by this contrivance, the wire may be lengthened or shortened at pleasure. To prepare the apparatus for use, the receiver Method of prdr o o is partly filled with the combustible gas; and is secured Par,nS lt f#r by wedges of cork v v, in the jar n w, the level of the water in the latter being regulated by opening the cock x or z. The bent pipe s *, with its cock r, is screwed upon the top of the receiver, and partly immersed in the water of a pneu- matic cistern, a «, so that the orifice of the burner may rise a few inches above the surface of the water. The receiver b b9 detached from the situation in which it is represented in the drawing, is then exhausted by an airpump; and, being filled with oxigen gas, is transferred (its mouth being closed during the act of removal with a piece of leather) to * I am indebted to Mr. H Creighton, of Soho, not only for a draw- ing of the apparatus, but for much raluable assistance in tht perform- ance of the experiments. the 88 APPARATUS FOR THE ANALYSIS OF GASSES. the cistern «, and quickly inverted over the burner t. By a little practice, this may be done with the admission of very little common air. A transferring vessel is then screwed upon the cock f; and a portion of oxigen gas removed for eudiometrical examination. To allow room for the expan- sion of the oxigen gas, the water is raised by a siphon to a proper height within the receiver b, as appears in the draw- ing, and of conduct- The apparatus being thus disposed, the cock f is con- tinent, nected by the chain h with the prime conductor of an elec- trical machine; and a rapid succession of sparks is made to pass between the copper ball at the end of the wire g, and the orifice of the burner. The cocks q and r being now opened, the stream of gas is kindled ; and in order to pre- vent the flame from playing upon the wire, the jar n n is moved a little nearer to the cistern a, which brings the point of the burner into the axis of the receiver. At the same time, by opening the cock x, water flows into the jar n w, and finds its way into the receiver, through two small holes w iv drilled near its mouth. The combustion continues, until either the whole of the inflammable gas is consumed, or till the cocks q and r are shut. The wedges v v are removed ; the receiver o o un^ screwed ; and the bent tube removed from its place* It is at this moment, that the cock r is useful, by preventing the escape of the gas from the receiver b through the tube s s. The upper part of the receiver is cooled by the application Calculation of of a wet sponge. Without waiting, however, till the gas the results. j^ Gained the temperature of the atmosphere, a very small and sensible thermometer is introduced into it; and the height of the mercury is noted, as soon as it becomes sta- tionary. The volume of the residuary gas is then observed, and is reduced by calculation to the bulk, which it would occupy at 60° of Fahrenheit. Either the whole, or an ali- quot part of it is removed by a transferring vessel, screwed upon the cock f> to a mercurial cistern, where the propor- tion of carbonic acid is determined by liquid potash. The proportions of oxigen and nitrogen gasses, in the unabsorbed residue, are learned by agitation with sulphuret of lime, observing the precaution* which have been stated by de Marti. APPARATUS FOR THE ANALYSIS OF GASSES. 89 Marti. The residuary oxigen being deducted from the quantity at the outset of the experiment shows how much qxigen has been expended in the combustion of the inflam- mable gas. It is scarcely necessary to observe, that the gasses are carefully reduced, at each stage of the operation, to a mean temperature and pressure, (60° of the thermome- ter, and 30 inches of the barometer)*. The process of combustion, as thus stated in general terms, appears sufficiently simple. It is often, however, ren- Source of w dered complicated by the imperfect combustion of the in- rour* flammable gas, a part of which escapes through the orifice of the burner, either wholly unaltered, or only partially burned. As this portion- is not absorbed by sulphuret of lime, it gives a fallacious appearance of an actual addition of nitrogen to the oxigen gas remaining in the receiver b. I .am unacquainted with any method of entirely obviating this difficulty ; but its amount may be diminished by an Precautions attention to certain precautions. With this view, the pres- a£ainst ll* sure upon the gas, contained in the receiver o o, should, on first opening the cocks q and r, be no more than is sufficient for its gentle expulsion through the tube s s. When, how- ever, the stream is once kindled, the larger the flame, and the more active the combustion, within certain limits, the more completely is the gas consumed. It is necessary, also, to stop the combustion, before it is rendered languid by the admixture of carbonic acid with the gas in the receiver b, and by the diminished purity of the oxigen gas. If this be not attended to, a large proportion of the inflammable gas, toward the close of the process, makes its escape unaltered into the receiver o. In general I have found, that, setting The more com- out with oxigen gas of equal purity, the more combus- bustiblethegas tible the inflammable gas submitted to experiment, the piete the" de- more complete is its decomposition by slow combustion.' The composition. apparatus, therefore, is better adapted to the analysis of ole- fiant gas, of carburetted hidrogen gas, or of mixtures of these two, than of carbonic oxide, or any gas of which this oxide forms a large proportion. * The rules observed in these calculations are stated in my Epitome of Chemistry, $th edition, p. 441. The 00 APPAllATUS FOR "THE ANALYSIS OF GASSES. Method of as- The inflammable gas, which has found its way into the lelkluTl'hidro- receiyer *> is always present in too minute a quantity to gen. compose, with the residuary oxigen, after the removal of the carbonic acid, a mixture capable of being inflamed by the electric spark. To ascertain its precise quantity, it is ne- cessary to have recourse to another operation. After trying, eudiometrically, the quality of an aliquot part of the gas in the receiver b, let a similar aliquot part be deprived of its carbonic acid, and then mixed with a portion of pure hi- drogen gas, not exceeding one third or one fourth the esti- mated bulk of the oxigen which it contains. Detonate the mixture, and observe the amount of- the diminution after the explosion ; the products of the combustion ; and the quantity of oxigen gas consumed. After subtracting, from the total expenditure of oxigen, half the bulk of the added hidrogen gas, the remaining number shows; kow much oxi- gen has been absorbed by the combustible gas contained in the residue. By the rule of proportion, it may be deter- mined, how much carbonic acid would have been produced* by the oxigenation of the whole of the combustible gas, and what quantity of oxigen it would have Saturated. Objection. The mosit obvious objection to this method of analyzing Absorption of ^e comp0und gasses is, that the real proportion of the pro- bonic acid by ducts, resulting from their combustion, may perhaps be the water. disguised, in consequence of the absorption of a part of the carbonic acid by the water, over which the experiment is made. By frequent trials, however, I find that this is a This trifiin". source of errour too trivial to be deserving of consideration ; and that the proportion of carbonic acid, thus generated, exceeds what is composed by the rapid combustion of the same gas over mercury. When the operator has acquired sufficient dexterity, the interval of time between the com- pletion of the combustion and the admeasurement of the residue is too small, to allow an absorption to any notable amount. It must be observed, also, that the carbonic acid constitutes only a small part of the residue ; and is, for this reason, very little acted on by water, conformable to a prin- ciple which I have explained in the Philosophical Transac- tions for 1803, p. 2/4*. I believe, therefore, that, with an •Journal, vol. V, p, 133. attention APPARATUS FOR THE ANALYSIS OF GASSFS. Q \ attention to those observances, which are required id all de- licate experiments on passes, and to the changing circum- stances of temperature and pressure, this apparatus is fully adequate to the purpose for which it is intended. It will be easy, however, for those, who have the command of a suffi- cient quantity of mercury, to adapt the apparatus to this fluid. As an exemplification of the method of using it, in the simplest possible case, I shall state the results of the combustion of hidrogen gas. At the outset of the experiment, there was contained in Results of the the receiver o o a quantity of hidrogen gas, equal, when j^?"**1"! of reduced to a mean temperature and pressure, to 15*8 cubic inches. Of these, there remained unconsumed 2*5 Hidrogen gas burned 13*3 In the receiver b were 49 cubic inches of oxigen gas, con- sisting of 33-5 oxigen, 15'5 nitrogen At the close of the experiment, there remained, in b, 43*5 c. i. composed of 27'25 l6'25 Cubic inches of oxigen gas con- sumed 6*25 But estimating from the first diminution (viz. 49 — 43*5} only 5'5 cubic inches of oxigen would appear to have been absorbed : and the nitrogen gas, by eudiometrical experi- ments, would seem to have b<-en increased 0*75 of an inch. As the hidrogen gas, however, had been prepared from zinc and sulphuric acid with extreme caution, and did not con- tain an appreciable quantity of common air, no such addi- tion of nitrogen could have taken place. The apparent in- crease, then, may be fairly imputed to the escape of 0*75 of an inch of hidrogen gas, which are to be deducted from the 13*3 cubic inches at the outset of the experiment; and hence the real quantity consumed will be 13*3 — 0*75 zz 12*55. The true consumption, also, of oxigen gas was 5*50 4- 0*75 — 6-25, or pretty exactly, as it ought to be, half the bulk of the hidrogen, which was actually burned. An f)G . APPARATUS FOR THE ANALYSIS OF GASSES. Experiments ^n example of the analysis of a highly combustible spe-» ' cies of elastic fluid is furnished by the following experiment* on the olefiant gas, obtained from alcohol and sulphuric acid. Of this gas 100 cubic inches, at a mean of the baro-> meter and thermometer, were equal to 30 troy grains; hence its specific gravity was 967. In the receiver o 0, were contained of this gas 6*3 cub. in* Residue , . . . . 2 Gas consumed • • 4*3 In the receiver b, were 43*4 inches of oxigen gas. After the combustion, there remained 38*2 cubic inches of mixed gasses, of which 8*6 were carbonic acid. None of the in- flammable gas, which passed through the bent tube, had escaped being burned, for the quantity of gas in b, not ab- sorbable by sulphuret of lime, so far from having been in- creased, was found to have sustained a trifling diminution. The oxigen gas, which was consumed, amounted to 13*8 cubic inches. Reducing these results to centesimal propor- tion, 100 cubic inches of this gas would give 200 of carbon nic acid, and absorb 325 of oxigen gas. This experiment agrees with Mr. Dalton's, as to the proportion of carbonic acid from the combustion of olefiant gas, but assigns a larger consumption of oxigen. It may be observed, how- ever, that the specific gravity of the gas, which I employed, exceeded a little the statement of the Dutch chemists, who found its specific gravity to be 909, common air being 1000. Gasses from Having satisfied myself, by repeated experiments, of the Tegetable sub- accuraCy 0f the results which may be thus obtaiued, I pro- ceeded to the combustion of the gasses from a variety of vegetable substances, and especially from those which it seemed probable might become economical sources of light. In the present memoir, I shall describe those only, which were made on coal and a few similar substances, reserving the rest for a future communication. Gas from cannel coah Gas from can- This was received in two separate portions. Of the first »ei coal. product, 100 cubic inches, corrected to a mean temperature' and APPARATUS FOR THE ANALYSIS OF GASSES. and pressure, weighed 24*28 grains. Hence its specific gravity was to that of atmospheric air as 783 to 1000. The second product was much lighter, 100 inches weighing only 10'4 grains, and having, therefore, the specific gravity of 335. The results are comprehended in the following table. The carbonic acid, stated to have been generated by the second combustion, was formed by adding to an aliquot part of the residue, after the removal of the carbonic acid, a proportion of hidrogen gas ; detonating the mixture by the electric spark; and proceeding as already directed. The first two lines contain the minutes of actual experiments; the third and fourth these results reduced to centesimal pro- portion. 93 Spec. Grav. 783 335 783 335 Cubic inches burned. Oxigen gas con- sumed. 7*3 9-8 100 100 16-5 9*4 222 96 Carbonic acid ge- nerated. Carb.ac. fbrm'd by 2d com bustion. 8-3 4-8 113-7 49 1-9 0 26 0 Ox. con- sumed by 2d com- bustion. o-9 0 12 0 Total oxigen consum- ed. 17*4 94 234 96 Total, carbonic- acid formed. 10-2 4-8 139-7 49 proportions The early product of the gas from can n el coal, before xhe first pro- being washed with lime water or caustic potash, is a mix- duct a mixture ture of several different gasses, viz. carbonic acid, sulphu- ° retted hidrogen, olefiant, and a fourth, which is either a gas sui generis , or a mixture of carburetted hidrogen, and car- Onesuigene- bonic oxide. To ascertain the proportion of these gasses in ns* any mixture, is a problem of some difficulty. Sulphuretted Method of as- hidrogen and olefiant gasses experience, it is well known, certaini!1^their an immediate condensation, when mingled with oximuriatic acid gas, and in this way they may be separated from car- bonic acid. Again, sulphuretted hidrogen and carbonic acid are absorbed by liquid potash, which has no action on olefiant gas. If, therefore, two equal portions of the gas from coal be mixed with oximuriatic gas, the one in its re- cent state, the other after being washed with potash, the condensation of the former will be found to exceed that of the washed portion. By the combined use of these agents, we may attain an approximation, at least, to the proportions in which carbonic acid, olefiant, and sulphuretted hidrogen gas g± APPARATUS FOR THE ANALYSIS OF GA5SF.S. gas are mingled with the aeriform product of coal. The General rule, rule may be stated as follows; to a measured quantity of oximuriatic acid gas, contained in a graduated tube, add twice its bulk of the recent coal gas, and at the expiration of one or two minutes observe the diminution which has taken place. Wash an equal quantity with caustic potash ; note the loss ; and submit the residue to the action of oxi- muriatic acid as before. The second diminution, thus ef- fected by oximuriatic gas, divided by 2*2, gives the propor- tion of olefiant gas. Deduct this absorption from the first, and, dividing the remainder by 1*8, we obtain the quantity of sulphuretted hidrogen. Lastly, to know the quantity of carbonic acid gas, subtract, from the diminution effected by potash, the amount of the sulphuretted hidrogen gas. An example, taken from actual experiment, will best explain the application of this rule, practical appli- One hundred measures of the first product of gas from nation of it. cannel coal lost, by agitation with liquid potash, 9*7 mea- sures. The remainder, being mingled with one fourth its bulk of oximuriatic acid gas, the mixture lost 10*4 measures. This diminution, 10*4, divided by 2*2, gives 4*9 for the proportion of olefiant gas. But 100 measures of the un- washed gas sustained, by admixture with oximuriatic acid, a diminution of 20 measures. Now, deducting, from this diminution, that occasioned by the condensation of olefiant -gas (viz. 20 — 10*4), there remain 9*6, which, divided by 1*8, give 5*3 for the proportion of sulphuretted hidrogen gas. And the diminution by potash (=9*7) — 5*3 gives 4*4 for the proportion of carbonic acid gas. Hence 100 measures of the first product of gas from cannel coal con- tain, First g:* from 1. Of inflammable gas, not affected by the «ftael cu*1' foregoing agents 85*4 2w Of sulphuretted hidrogen gas • 5*3 3. Of olefiant gas 4*9 4. Of carbonic acid gas t ...... . 4*4 100 The APPARATUS FOR THE ANALYSIS OF CASSES. DS The proportion of common air, in the foregoing speei- VeI7 Iktk men of gas, and in all cases when care was taken to exclude it, was too small to deserve being taken into the account, not appearing, by the test of nitrous gas, to exceed 1 per cent. The following table exhibits the composition of gas from Composition of, various kinds of coal. In the last column, under the term Sas flom diffe; . . rent coals, and inflammable gas, is comprehended that portion, which is bitumens. neither suddenly condensed by oxi muriatic acid gas, nor absorbed by potash. A name more descriptive cannot be applied to it, because it varies essentially in different cases, and the proportion of its components is still matter oP doubt, TABLE L Kind of coal. 1 No. of I the [product 100 measures consisted of Sulph hid. Curb, acid. de- fiant. lnflam. Wigan cannel < Wed nesbury, Stafford sh. 1 Newcastle on Tyne* ••• < Newcastle, Staffordshire < Middleton, near Leeds < Black Mine, near Man- chester • • • • • . Merthyr, Glamorgansh. Native coal tar- Caoutchouc « • < 5-3 0. 4-9 0- 2-9 2*2 3 1*4 0 3 1*4 0 3 3 2 2 0-5 0 0 1 0 0 0 0 0 13 0 4-4 1-8 3*4 2*8 2-8 1-7 .27 2 1-4 2* 1*7 2 3 1 1 1 1 0 1-7 1*7 1-6 1*5 r o 6 4-9 4-9 0 0 0 2-7 0 0 0 0 1 0 0 2*5 0 0 0 0 0 0 0 0 0 0 0 15 17 85-4 98*2 91-7 97*2 91-6 96-1 94-3 90-6 98-6 94 96-9 98- 91 96-9 97 98*3 98*8 100 97-3 98-3 98-4 98-5 99 100 66 78'1 After 9(J APPARATUS FOR THE ANALYSIS OF GASSES. After separating the sulphuretted hidrogen and carbonic acid gasses by agitation with liquid potash, the residue, con- sisting of the inflammable gas mixed with the proportion of olefiant gas produced along with it, was submitted to com- bustion. The following table shows the average results of a number of these experiments. TABLE II. Weight ot Spec. No of 100 cubic 100 cubic inches Kind of coal. the product inches (Ther. 60° grav. (Air 1000.) consume give carbo- Bur. 30°.) oxig. gas nic acid. Grs. llesuTh; of the Wigan cannel • • •< combustion of £ 1 2 24*28 10-4 783 335 234 96 139*7 49 the influmma- Wednesbury coal 5 blc gas. * I 1 f 20-9 674 190 97*5 9*8 310 85 46 Newcastle on j Tyne \ 1 19*3 622 190 100 2 9'8 310 86 45 Newcastle, Staf-S 1 19*6 632 195 98 fordshire • • • • y 2 17*7 570 165 80 3 ISjl •390 100 60 f 1 20*7 670 190 100 Leeds ■{ o 15-1 487 lost by accident. I 3 9*8 316 85 > 42 1 19*4 O27 186 97 m 2 15 484 137 • 65 Black Mine, 1 3 11-3 364 100 50 Lancashire • • J 4 10 322 90 47 f 5 9-5 307 85 45 Vj 6 80 40 r 1 12 387 117 62 \ ^2 9'5 307 90 47 Merthyr ...... <^ 3 8 261 75 39 4 5*9 190 ()'() 31 1 5 5*8 187 57 26 V. 6 5-5 177 50 20 Coal tar - 24-2 780 233 150 Caoutchouc i — 204 121 General obser- Yations. defiant gas. An attentive examination of the results, contained in both the tables, suggests the following general remarks. 1. The olefiant gas is a very sparing product of the dis- tillation of pit coal. It is found only in the tirst portions, aud even of these it does not compose more than 5 per cent. Its APPARATUS FOR THE ANALYSIS OF GASSEg, QJ Its quantify, however, is very much influenced by the tern- Result much perature employed. This remark, indeed, may be extended ^^hTaTem-7 to all the aeriform products of coal; insomuch that from ployed, equal weights of the same coal it is difficult to obtain by different operations, conducted on a small scale, products which are the same either in quantity or quality. The gas from Coulbrooke dale tar, and that from caoutchouc^ have a larger proportion of olehant gas, which in them amounts to about one sixth of their bulk* 2. Sulphuretted hidrogen gas is, also, most abundantly Sulphuretted produced at the early stages of the distillation. Its pro- hldrcSeu* portion then varies from 1 to 5 percent; and towards the close of the process it disappears entirely. It increases the illuminating power of the coal gas; but is by no means a desirable product; since it yields by combustion a gas (the sulphurous acid) which is extremely offensive and irritating to the lungs. By the distillation of coal, more sulphuretted hidrogen is produced, than is discovered among the aeriform products; for a part, uniting with the ammonia, which is generated at the same moment, forms sulphuret of ammo- Sulphuretcf nia, a compound which I have found among the condensed ammonia, products. 3. Carbonic acid gas, like the two preceding ones, ap- Carbonic acid* pears only at an early stage of the process, and in small proportion, never amounting to 5 per cent. A portion of this gas, also, unites with ammonia, and hence carbonate of ammonia is found in the condensed fluid. 4. The gas from coal undergoes a gradual diminution ofTheprodurt specific gravity and combustibility, from the commence- graduflly. di" 1 r> j . minishes m ment to the close of the process. This is best shown by gravity and inspecting the results of the experiments on the Black* combustibility. Mine and MertKyr coal gas in Table II, because they were reserved in a greater number of separate portions than usual. The progression would, perhaps, have been more regular, in these as well as in the other instances, if much of the gas had not been allowed to escape, in consequence of the immense quantity which was produced. The speci- fic gravity of the coal gas appears to afford a measure of its fitness for illumination, sufficiently accurate fur practical uses; but does not bear an exact correspondence to the Vol,. XXII. Feb. 180Q. H chemical <)8 APPARATUS FOR THE ANALYSIS 0? GASSES. chemical properties of the gas, as ascertained by combtts- Carbomcndc] t\0lu [t may be remarked, also by comparing the two last not always in . * J r ° proportion to columns or the second table, that the carbonic acid pro-* the oxigen ex- duced does not always bear the same proportion to the oxi- -**1 e ' gen expended. Thus the first product of gas from cannel coal combines with 234 measures of oxigen gas; and gives 139*7 of carbonic acid. But the gas from coal tar, with only an equal consumption of oxigen, yields 150 measures of carbonic acid. Coal gas not 5* The aeriform product of coal does not precisely answer acilywith any to tne characters of any one of the combustible gasses, with other combus- which we are acquainted. The first product, however, of the distillation of ciminoa pift coal, after being washed with potash, approaches very nearly in its properties to carburet- ted hidrogen gas. The gasses, which surpass this in speci- fic gravity, are mixtures of carburetted hidrogen with ole- fiant gas, and perhaps a small proportion of carbonic oxide. The lighter gasses, in addition to carburetted hidrogen,- probably contain a variable proportion of hidrogen gas and a small quantity of carbonic oxide. The extreme levity of some of the products, especially of the gas from Merthyr coal, cannot be explained on any other supposition. Product. ofthe 6. The products of the combustion of a cubic foot of coaUas?0*1 °f coal Sas> of medium quatoy, viz. of the specific gravity 622, (such as the first products from Newcastle on Tyjie coal) may be stated as follows: A cubic foot, at a mean of the barometer and ther- Grain;?. mometer 333*5 By combustion, it yields 817'3 grains of carbonic acid, the carbon in which may be estimated* at* • 033.7 Grains of hidrogen in a cubic foot of coal gas. . . . 99*8 But 99*8 grains of hidrogen are equivalent to the satura- tion of 554*9 grains of oxigen, with which they form 654*7 grains of water. Hence the oxigen consumed ought from calculation to be 8 1 7*3 — 233*7 = 673-6-f 554*9= H2S And the quantity actually consumed appears by experiment to be • • • • 11 1 0*3 Errour 17*7 * Assuming the carbon to be 28 6 grains in 100 grains of carbonic *cid, as is satisfactorily proved by the experiments of Messrs. Allen and Itlfr* The APPARATUS FOR THE ANALYSTS OF GASSES. 99 The difference, in this example, between experiment and calculation is not greater, than, in such delicate processes, may always be expected. A part of the deficiency in the oxigen actually consumed, may be ascribed, also, to a small portion of the inflammable gas being already in the state of carbonic oxide. Without repeating the particulars of a similar calculation made on gas of an inferior quality, I shall annex a compa- rative statement of the specific gravities and composition of the good and inferior gasses* Source of* the Gas. Newcastle coal Ditto, last product Weight of a Cubic Foot. 333*5 gr 169-3 A Cubic Foot consists of Carb | Huh. 99'8 57*8 2337 111-5 Oxig'*n Gas consum- ed by a Cub. Ft ill0:3 560- Gives Difference be- tween the best and inferior 817'3|G21 400 384-9 The inferior gas, also, probably contains carbonic oxide; and the quantity of oxigen gas, actually consumed, will be found, on calculation, less than it ought to be, if the car- bon were not already combined with a portion of oxigen. The quantity of water, which was venerated by combus- . ,i, ., . °. , . . The water e3- tion, was not determined experimentally, but is merely es- timated. timated. It must be acknowledged, that the decomposition . of the inflammable gasses cannot lead to unquestionable results, until the proportion of water, produced by their combustion, is also accurately ascertained. With the view of effecting this, I have already spent much time, and em- ployed many contrivances, none of which have satisfactorily answered the purpose for which they were intended. 7. There appears to be a considerable difference in the specific gravity and combustibility of gas from various spe- cimens of coal, even when taken at similar periods of the distillation. The coal from Merthyr in South Wales, which Gas froin c0^ burns without flame or smoke, yields a gas, which contains, burning with- in an equal volume, scarcely half as much combustible out P11™6 or matter as the gas from Wigan cannel. This will probably be found to be the case with respect to all coal of similar H 2 quality, 100 IRREGULARITY OF THE PLANET SATtJRN.- quality, among which ftuty be reckoned the Kilkenny couL abunda'Ttie *^ne niost important difference among the< varieties of this gas, the more miner*al, connected with their application as sources of light, rifi^atiorT *** consIsts m ^e quantity of sulphuretted hidrogen gas, which is mixed with their aeriform products} and it unfortunately happens, that the coal, otherwise best adapted to this pur- pose, yields generally the largest proportion of this offensive Best mode of gas. The only effectual method of purifying the coal gas purifying it. from suiphuretted hidrogen, on the large ncale of manufac- ture, will probably be found to consist in agitation with quicklime and water, composing a mixture of the consis- tence of cream. Simple washing with water by no means effects the complete separation. Condensable , jn tjie experiments which were made on the products of ed. the distillation of coal, I purposely neglected the amount and analysis of the condensible fluids, because they cannot be advantageously ascertained by the same operation with the elastic ones. They may also be much better determined On the large scale of manufacture^ thauvby limited experi- ments. For the same reason t was not solicitous to mea- sure even the aeriform fluids ; and on this subject, I believe, more accurate information has been communicated by Mr. Murdoch, than it was in my power to acquire. Manchester , May 19, 1808. m. Account of a new irregularity lately perceived in the appa- rent Figure of the Planet Saturn. By William IIers- chel, LL. D. F. R. S*. Singular figu.c Jj HE singular figure of Saturn, of which I have given an account in two papersf, has continued, for several reasons, to claim my attention. When I saw the uncommon flatten- * Philos. Trans, for 1808, p. 159. -\ Sec our Journal, vol. XIII, p. '4. IRREGULARITY OF THE PLAKET SATURN. JQ1 ing of the polar regions of this planet in the 40-feet teles- Cdpe, I ascribed it to the attractive matter in the ring$, and of its tendency to produce such an eiVe.ct we can have no doubt; but as another circumstance, which was also no-r Not wholly ticed, namely, an apparent small flattening of the equato- Jj^ttrartiS rial parts, cannot be explained on the same principles, I of the ring. wished to ascertain what physical cause might be assigned for this effect, and with a view to an investigation of this point, I have continued my observations^ The position of the ring, at the last appearance of the planet, however, proved to be quite unfavourable for the intended purpose; for the very parts, which I was desirous of inspecting, were covered by the passage of the ring over the disk of the planet iu front, or were projected on the ring, where it passed behind the body. In my attempts to pursue this object, I perceived a new Recent charge irregularity in the Saturnian figure, which, I am perfectly as- m ,ts fi.8ure» sured, had no existence the last time I examined the planet, and the following observations contain an account of it. Observations. .June 16, 1807. The two polar regions of Saturn are at The two poles present of a very different apparent shape. The northern dlffer* regions, as iu former observations, are flattened; but the southern are more curved or bulged outwards. I asked my son John Herschel, who after me looked at Saturn while 1 was writing down the above observation, if he perceived, that there was a difference in the curvature of the north and south pole; and if he did, to mark on a slate how it appeared to him. When I examined the slate. I found that he had exactly delineated the appearance I have de- scribed. In a letter to a very intelligent astronomical friend*, who 1 has one of my 7-feet reflectors, I requested the favour of him to examine both the polar regions of Saturn, and to let \ See Phil. Trans, for 1805, p. 276 ; or Journal, vol. xiii, p. 8. • Dr. Wilson of Hampstead, late Professor of Astronomy at Glasgow. me 102 IRREGULARITY OF THE PLANET SATURN, me know whether he could perceive any difference in the ap- pearance of their curvature; in answer to which I received, the 23d of June, a letter enclosing a drawing, in which also the southern regions were marked as more protuberant, with a greater falling off close to the irregularity. My friend, with his usual precaution, calle&ithis an illusion; and it will be seen by and by, that we shall have no occasion to ascribe this irregularity to a real want of due proportion, or settled figure of the polar regions of Saturn. June 22, 9n 24'. I see the same curved appearance at the south pole of Saturn, which was observed the l6th. June 24. The air is very clear, and all the most critical phenomena are very distinctly to be seen ; the shadow of the ring towards the south upon the planet; the shadow of the body towards the north-following side upon the ring; the belts upon the body ; the division of the two rings; and with the same distinctness, I also see the protuberance of the south pole. Not a distortion My seeing this appearance, at present, is a proof, that it °f f0"1! r^" *s not a phys»cal irregularity or distortion of only some par- the polar re- ticular spot on the polar regions; for, in that case, it could ?l0n' not have been seen this evening, as from the rotation of the planet on its axis, which is lOh l6', the space of the polar circle which is now exposed to our view must have been very different from what I saw the l6th and 22d. Many observations were made afterward, which all confirm the reality of this appearance. It is probably It is so natural for us to reflect upon the cause of a new an illusion, phenomenon, that I cannot forbear giving an opinion on this subject. To suppose a real change in the whole zone of the planet, cannot be probable ; it seems therefore, that this ap- pearance must be, as my friend calls it, an illusion. But since the reality of this illusion, if I may use the expression, has been ascertained by observation, it is certain, that there irrust be some extrinsic cause for its appearance; and also that the same cause must not act upon the northern hemis- phere. Now the only difference in the circumstances under which the two polar regions of Saturn were seen in the fore- going IRREGULARITY OF THE PLANET SATURN ] 03 going observations is the situation of its ring, which passes before the planet at the south, but behind at the north. The ravs of li^ht therefore, which come to the eye from the owin^o the ' 5 . . , « , L • it position ot the very small remaining southern zone ot the saturman globe, rillg between pass at no great distance by the edge of the ring, while those the eye and , n -i- ^ ^ tuis region, from the north traverse a space clear of every object that might disturb their course. If therefore we are in the right to ascribe the observed illusion to an approximate interpo- sition of the ring, we have, in the case under consideration, only two known causes, that can modify light so as to turn it out of its course, which are inflection and refraction. The insufficiency of the first to account for the lifting up of the protuberant small segment of the southern regions will not require a proof. The effects of refraction on the contrary are known to be very considerable. Let us there- fore examine a few of the particulars of the case. The greatest elevation of the visible segment above the ring did not amount to more than one second and three or four tenths. Then supposing the ring, the edge of which is pro- the ring haying bably of an elliptical figure, to have a surrounding atmos- JJ SKm*? phere, it will most likely partake of the same form, and the rays of light rays which pass over its edge will undergo a double refrac- arc ren"acte(i' tion : the first on their entrance into this atmosphere, and the second at their leaving it, and these refractions seem to be sufficient to produce the observed elevation. For should they raise the protuberant appearance only half a second, or even less, the segment could no longer range with the rest of the globe of Saturn, but must assume the appear- ance of a different curvature or bulge outwards. The refractive power of an atmosphere of the ring has The refractive been mentioned in a former paper*, when the smallest satel- Power of this, t. ^ -. ' t • ill atmosphere aU lites of Saturn were seen as it were bisected by the narrow ready shown, luminous lines under which form the ring appeared when' the Earth was nearly in the plane of it; and the phenome- non, of which the particulars have now been described, ap- pears to be a second instance in support of the former. « See Phil. Tans, for 1790, page 7. IV. 104- HYDRAULIC INVESTIGATIONS, IV. Hydraulic Investigations, subservient to an intended Croo- nian Lecture on the Motion of the Shod* By Thomas Young, M. D. For. Sec. K. S*. I. Of the Friction and Discharge of Fluids running in Pipes, and of the Velocity of Rivers. Motion of JlJL AVING lately fixed on the discussion of the nature of fluids in flexi- inflammation, for the subject of an academical exercise, I pie clastic J tube». found it necessary to examine attentively the mechanical principles of the circulation of the blood, and to investigate minutely and comprehensively the motion of fluids in pipes, as affected by friction, the resistance occasioned by flexure, the laws of the propagation of an impulse through the fluid contained in an elastic tube, the magnitude of a pulsation in different parts of a conical vessel, and the effect of a con- traction advancing progressively through the length of a given canal. The physiological application of the results of these inquiries I shall have the honour of laying before the Royal Society at a future time; but I have thought it advisable to communicate, in a separate paper, such conclu- sions, as may be interesting to some persons, who do not concern themselves with disquisitions of a physiological na-( ture ; and 1 imagine it may be as agreeable to the Society, that they should be submitted at present to their considera- tion, as that they should be withheld until the time appoint- ed for the delivery of the Croonian Lecture. Dubuat's cal- It has been observed by the late Professor Robison, that dilations agree tjje comparison of the Chevalier Dubuat's calculations with ment?Xpen" bis experiments is in all respects extremely satisfactory; that it exhibits a beautiful specimen of the means of ex- pressing the general result of an extensive series of obser- vations in an analytical formula, and that it does honour to the penetration, skill, and address of Mr. Dubuat, and of •Pbilos. Trans, for 1808, p. 164. k Mr. HYDRAULIC INVESTIGATIONS. 10J Mv. de St. Honore, who assisted him in the construction of his expressions. I am by no means disposed to dissent from this encomium ; and I a^ree with Professor llobison, and with all other late authors on hydraulics, in applauding the unusually accurate coincidence between these theorems and the experiments from which they were deduced. But I The form of have already taken the liberty of remarking, in my lecture not very con„ on the history of hydraulics, that the form of these expres- venient for sions is by no means so convenient for practice as it might have been rendered; and they are also liable to still greater objections in particular cases, since, when the pipe is either extremely narrow, or extremely long, they become com- \n somc cases pletely .erroneous : for notwithstanding Mr. Dubuat seems erroneous« to be of opinion, that a canal may have a finite inclination, and yet the water contained in it may remain perfectly at rest, and that no farce can be sufficient, to make water flow in any finite quantity through a tube less than one twenty- fifth of an inch in diameter; it can scarcely require an ar- gument to show, that he is mistaken in both these respects. It was therefore necessary for my purpose to substitute, for the formula? of Mr. Dubuat, others of a totally different nature; and I could follow Dubuat in nothing but in his general mode of considering a part of the pressure, or of the height of a given reservoir, as employed in overcoming the friction of the pipe through which the water flows out of it; a principle, which, if not of his original invention, was certainly first reduced by him into a practical form. By A formula Hence the ve- Hence it is easy to calculate the velocity for any given pipe locity may or river, and with any given head of water. For the height ilto/fbrtty" required for producing the velocity, independently of fric- pipe or river v% with any head. tion, is, according to Dubuat, — , or rather, as it appears from almost all the experiments which I have compared, — ; and the whole height h is therefore equal to /-f ~ • /al 1 V 2c/ 1 %\ =1 Vd t ssi) I * Tv> and^aki"S5=^4^oTi^ and HYDRAULIC INVESTIGATIONS. |07 bd and e zz ~r, v7, 4- 2ev — bkt whence v = -/ (6/t + 0000^). In order to show the agreement of these formulae with Various exp*. the result of observation, I have extracted, as indiscrimi- "^Withthe nately and impartially as possible, forty of the experiments formula. made and collected by Dubuat; I have added to these some of Gerstner's, with a few of my own ; and I have compared the results of these experiments with Dubuat's calculations, and with iny own formula^ in separate columns. There are six of Dubuat's experiments, which he has rejected as irre- gular, apparently without any very sufficient reason, since he has accidentally mentioned, that some of them were made with great care: I have therefore calculated the velocities for these experiments in both ways, and compared the re- sults in a separate table. Tabular 308 HTDRAl'UC INVESTIGATIONS. Tabular Comparison of Hydraulic Experiments. Observer d. PUBUAT J62-5 258-5 924 75 6 17-6 164 11-7 99 5-8 Sup erf. Veloc. Dub 3$7l23 641,3 21887 27648 *>28H 432 1412 427 212 1596 12-56?' 31-77 .•6-63? 9 61 7 01? 7-27 507? 5-70 32*52 1417 22-37 2751 1 10-53 28-76 8-38 655 5-86 31-61 13-59 24-37 12 7- 19 Log. ratio. Y. •0776 •0334' 0775 •1112 0120 0124 0182 •0372 •0051 11-10 28-02 8-14 6-27 5-97 30 67 14-05 24-41 27-34 Log. a ratio. •l'X •0537 424 • •d221 424 ' •0649 415 0923 413 •0291 376 •0255 374 0037 360 •0379 355 1-0027 352 c L* 952 952 914 887 465 451 416 414 466 0!69 1040) Gejistnexi, HTDH.AULIC INVESTICV.VMOXS'. 10.9 LW. Log. Observers J. /. h. t\ Dub. rat. Y. rat. a. c. Gkhstniiii, di jb-b°F. 2 63 10.7 24-2 23-0 •006 24-1 •002 349 2533 7-7 21-0 19-9 •023 19'1 •042 47 158 149 •026 139 •056 1:7 H 8-2 039 69 •036 •7 2-5 50 '301 3-4 •133 ■li-3 33 10-7 27-1 23'4 •064 S«-fi 081 488 3259 1:7 23-2 i94 •077 185 •098 47 154 14-6 •024 135 •058 17 56 81 '.60 0-7 •078 •7 2-3 4 6 •30-1 3-4 •169 •0674 33 10-7 10f> 8-9 •051 101 •004 975 570O 7'7 7-2 7-4 •012 8-2 •057 4-7 45 56 •095 56 •095 i-t r:> 3-1 •316 2-5 •222 •71 •5 18 •444 It •342 (Mean -129=L. 1-346 098=L. 1'254) tf. at 60°. DlTBt!AT. ♦V 8 50 32-4 14-40 o oo 13-36-032 2956 1 T6T 3 42 30-0 •53 •32 -008 13404 1*17 58 •2? SO 1 -046 (Mean -029 2 1 255-25 24 36-35 36-25 27 86 31 122-59 106-45 84-85 59-25 118-07 84-2 11/-8 101-1 82-2 57-5 111-5 •011 018 •022 •013 | •013 ■027 79-7 120-8 104-1 84 8 59-7 118-5 •035 •007 •010 •000 •004 •000 287 259 4 18 9 27-08 13882 452100 747 1063 (Mean •0l7=L.l,041 009=L. 10S it appears from this comparison, that in the forty experi- Accuracy of ments extracted from the collection, which served as a basis the two for~ , mulx com- for Dubuat's calculations, the mean errour of his formula pared, is T'T of the whole velocity, and that of mine JT only ; but if we omit the four experiments, in which the superficial velocity only of a river was observed, and in which I have calculated the mean velocity by D ubu at' s rules, the mean errour of the remaining 36 is ^ according to my mode of calculation, and -^y according to Mr. Dubuat's; so that on the whole, the accuracy of the two formulae may be con- sidered as precisely equal with respect to these experiments. In HO HYDRAULIC INVESTIGATION*. In the six experiments which Dubuat has wholly rejected, the mean errour of his formula is about t't> an^ tnat of mine TV» In fifteen of Ger.-tner's experiments, the mean errour of Dubuat's rule is one third, that of mine one fourth ; and in the three experiments which I made with very fine tubes, the errour of my own rules is one fifteenth vf the whole, while in such cases Dubuat's formulae com- pletely fail. I have determined the mean errour by adding together the logarithmic ratios of all the results, and divid- ing the sum by the number of experiments. It would be useless to seek for a much greater degree of accuracy, un- less it were probable, that the errours of the experiments themselves were less than those of the calculations; but if a -sufficient number of extremely accurate and frequently repeated experiments could be obtained, it would be very possible, to adapt my formula still more correctly to their results. i In order to facilitate the computation, I have made a ta- ble of the coefficients a and c for the different values of d, all the measures being still expressed in French inches. Table of Coefficients for French Inches. d a ' •i7 X c •l7 X i •i7 X c •17 X d a •17 X c •l7 X 00 430 900 15 370 427 1 7 249 1278 500 427 943 10 354 414 •6 248 1384 400 426 946 9 350 421 •5 249 1524 300 423 950 8 345 433 •4 257 1717 200 421 951 7 340 440 i 268 1895 100 416 923 6 335 462 •3 279 2008 .90 415 911 5 325 512 i 4 303 2225 80 413 896 4 319 540 •2 349 2532 70 410 872 3 305 617 1 0 402 2827 60 408 840 2-5 296 687 •15 440 3026 50 406 792 2 288 751 I 458 3116 40 400 719 1-5 275 866 * 518 3405 30 393 618 1 259 1063 JL 589 3693 25 387 500 •9 255 1123 •1 646 3935 20 ^- — 380 492 •8 252 1193 ' ■■ — For HYDRAULIC INVESTIGATIONS. Hi 3Tor example, in the last experiment, where d is 1, / 4, j^™^!^* _ 1 cienu. and h 27*1, we have a =z -000025Q, b == ~JTJ^{-~7001S2 W 516", c == -0001063, ezzbclidzz "22, and v = that the value, thus determined, became too great when rf was about 20, and too small in some other cases. Coulomb's experiments on the friction of fluids, made by means of the torsion of wires, give about '00014 for the value of c, which agrees as nearly with this table, as any constant number could be expected to do. I have however reason to think, from some experi- ments communicated to me by Mr. Robertson Buchanan, that the value of a, for pipes about half an inch in diame- ter, is somewhat too small; my mode of calculation, as well as Dubuat's, giving too great a velocity in such cases. If auy person should be desirous of making use of I)u- Assistants t» buat's formula, it would still be a great convenience to be- Dubuat's for" gin by determining v according to this method; then, tak- ing b zz » v%. 478> or rather, as Langsdorf makes it, b rr h — v%' 482* to Procee(* m calculating v by the formula v zz 148-5 (•<*--) • (^h-HAL* [b+l-6)—°°l)> since this determination of b will, in general, be far more accurate than the simple expression b zz — -r and the continued repetition of the calculation, with approximate values of v, may thus be avoided. Sometimes, indeed, the values of v found by this repetition will constitute a diverg- ing instead of a converging series, and in such cases, we can only employ a conjectural value of v, intermediate be- tween the two preceding ones. Having sufficiently examined the accuracy of my for- The formula ■aula, I shall now reduce it into English inches, and shall reduced to , English roea- add sure. 112 HYDRAULIC INVESTIGATIONS, add a second table of the coefficients, for assisting the cal- 75 culation. In this case, a becomes -0000001 (413 4- "J*-— 1440 180 \ / QOOdd 1 dV^i-dV'sToh c - ,0000001 {ddTTm * Vd 13*21 1*0563\ 1 (1085 + — d~ + ~dd~)\ and h -^TT-^oTtT' *bemg #c/ /V/$ rex c -^~, and ». = y \hh + e%) — 10Q 399 918 6 322 471 •3 2S0 2082 90 398 903 5 312 507 1 T 305 2307 80 396 885 4 30G 556 •2 354 2631 70 393 860 3 292 635 1 409 2943 60 391 825 2'5 284 694 °-l'5 447 3150 50 389 772 2 277 774. 1 7" 466 3351 40 383 6y 8 1-5 266 894 1 528 355S 30 377 597 1 251 1099 ttt 599 3866 25 371 526 •9 248 11 61 •1 657 4183 20 364 482 "8 245 1234 II. Of the Resistance occasioned by Flexure in Pipes or E vers. Mr. Dubuat has made some experiments on the effect perimentsou tn^ flexure °» a V^Pe in retarding the motion of the watt effect oiflcxure flowing through it; but they do not appear to be by ai in a pipe. ■ " Xl meai Hydraulic investigations. fjg means sufficient t» authorise the conclusions, which he has drawn from them. lie directs the squares of the sines of His rule the angles of flexure to* be collected into one sum, which, being multiplied by a certain constant coefficient, and by the square of the velocity $ is to show the height required for overcoming the resistance. It is, however, easy to see, that fundamentally - such a rule must be fundamentally erroneous, and its coin- cidence with some experiments merely accidental, since the results afforded by it must vary according to the method of stating the problem, which is entirely arbitrary. Thus it depended only on Mr. Dubuat to consider a pipe bent to an angle of 144° as consisting of a single flexure, as composed of two flexures of 72° each, or of a much greater number of smaller flexures; although the result of the experiment would only agree with the arbitrary division into two parts, which he has adopted. This difficulty is attached to every mode of computing the effect either from the squares of the sines or from the sines themselves; and the only way of avoiding it is to attend rilerely to the angle of flexure as expressed in degrees. It is natural to suppose, that the ef- A different feet of the curvature must increase, as the curvature itself tne0r7, increases, and that the retardation must be inversely pro- portional to the radius of curvature, or very nearly so ; and Sufficiently this supposition is sufficiently confirmed by the experiments experiment/ which Mi. Dubuat has employed in support of a theory so different. It might be expected, that an equal curvature would create a greater resistance in a larger pipe than in a smaller, since the inequality in the motions of the different parts of the fluid is greater ; but this circumstance does not seem to have influenced the results of the experiments made ' with pipes of an inch and of two inches diameter : there must also be some deviation from the general law in cases of very small pipes having a great curvature, but this devia- tion cannot be determined without farther experiments. Of the 2o which Dubuat has made, he has rejected 10 as irre- gular, because they do not agree with his theory : indeed 4 of them, which were made with a much shorter pipe than the rest, differ so manifestly from them, that they cannot be reconciled : but 5 others agree sufficiently, as well as all the rest, with the theory which I have here proposed, supposing Vol. XXII.— Feb. 1809. I th« J14 HYDRAULIC INVESTIGATIONS. the resistance to be as the angular flexure, and to increase besides almost in the fiavne proportion as the radius of cur- vature diminishes, but more nearly as that power of the ra- dius of which the index is •£. Thus if p be the number of degrees subtended at the centre of flexnre, and q the radius of curvature of the axis of the pipe in French inches, we shall have r pv' 200000 q nearly, or, more accurately, r =p •0000045 pv^q* . These calculations are compared with the whole of Dubuat's experiments in the following table. Table of Experiments on the Resistance occasioned by Flexure, p 9 v% r B. Y.l Y.2 288 3.22 15030 4-75 6-71 6-98 11330 3-50 5-06 5-26 7199 2*33 3-21 3-34 3510 1-08 1-56 1-62 Sl6 7216 2-49 2*49 2*42 2-52 144 1-50 1-66 1-61 1-67 72 •75 •83 •80 •83 196-5 6-12 1-50 1-66 1-16 1-31 147-4 1-12 1-24 •87 •98 98*3 •75 •83 •58 -65 40*1 •37 •41 •29 •33 112'5 •53 6-00 7-68 6-36 99 5-90 6-74 5-60 •88 3-22 3415 1-50 1-57 1-52 1-58 288 3*22 3415 1-50 1-57 1-52 1-58 144 •75 •78 •76 •79 72 •37 '39 •38 •39 196-5 6-12 •75 •78 •55 •62 112-5 •53 1-50 3-63 3-00 720 3'22 5125 5-90 5-90 5-72 5-95 288 3458 1-64 1-59 1-54 1-60 860 821 •41 •40 •38 •37 •40 ■ ■ •39 •38 •38 288 4-10 3448 T33 1*21 1-30 7449 2*90 2-59 2*78 294*8 9*9 7 360 4-1 } B'64 I 8*08 8'62 112*5 l'l i ■ 1 la HYDRAULIC INVESTIGATIONS. ] 15 Iii the last three experiments, the diameter of the pip* Remarks. Was two inches. The radius of curvature is not ascertained within the tenth of an inch, as Dubuat has not mentioned the thickness of the pipes. The mean errour of his formula iu fifteen experiments, and of mine in twenty, is TV 0I tne whole. III. Of the Propagation of an Impulse through an Elastic Tube. The same reasoning, that Is employed for determining Propagation, of the velocity of an impulse, transmitted through an e^j^C through an solid or fluid body, is also applicable to the case* of an in- elastic tube, compressible fluid contained in an elastic pipe; the magni- tude of the modulus being properly determined, according to the excess of pressure which any additional tension of the pipe is capable of producing; its height being such, as to produce a tension, which is to any small increase of tension produced by the approach of two sections of the fluid in the pipe, as their distance to its decrement: for in this case the forces concerned are precisely similar to those, which are employed in the transmission of an impulse through a co- lumn of air enclosed in a tube, or through an elastic solid. If the nature of the pipe be such, that its elastic force va- Propositions. ries as the excess of its circumference or diameter above the natural extent, which is nearly the usual constitution of elastic bodies, it may be shown, that there is a certain finite height which will cause an infinite extension, and that the height of the modulus of elasticity, for each point, is equal to half its height above the base of this imaginary column ; which may therefore be called with propriety the modular column of the pipe : consequently the velocity of an im- pulse will be at every point equal to half of that which is due to the height of the point above the base; and the velo- city of an impulse ascending throeigh the pipe being every where half as great as that of a body falling through the corresponding point in the modular column, the whole time of ascent will be precisely twice as great as that of the de- scent of the falling body ; and in the same manner if the pipe be inclined, the motion of the impulse may be com- I 2 pared \\S HYDRAULIC INVESTIGATIONS. pared with that of a body descending or ascending freely along an inclined plane. Demonstration. These propositions may be thus demonstrated : let a be the diameter of the pipe in its most natural state, and let this diameter be increased to 6 by the pressure of the co- lumn c, the tube being so constituted!, that the tension may vary as the force. Then the relative force of the column c is represented by b <*, since its effieacy increases, according to the laws of hydrostatics, in the ratio of the diameter of the tube; and this force must be equal, in a state of equili- brium, to the tension arising from the change from a to b, that is, to b- — a; consequently, the height c varies as — - — ; and if the tube be enlarged to any diameter x, the 6 corresponding pressure required to distend it will be ex- * pressed by a height of the column equal to ( 1 V- h-^ a x^—a s a \ b c — : ( 1 — — } . Now if the dia- v \ x J b — « since — j — : c : b meter be enlarged in such a degree, that the length of a cer- tain portion of its contents may be contracted in the ratio 1 : l— «r, r being very small, then the enlargement will b% 7" T X in the ratio 1:1 + -— > *hat ls> x' w^ ^>e ~* but tne incre- Q x' be ment of the force, or of the height, is — . , which will xx b — a become — . . Now in a tube filled with an elastic c2x b — a fluid, the height being h, the force in similar circumstances would be r h, and if we make hzz — . , the velocity 2x b-^-a J of the propagation of an impulse will be the same in both cases, and will be equal to the velocity of a body which has fallen through the height f k. Supposing x infinite, the height capable of producing the necessary pressure becomes b c , which may be called g, and for every other value of b-~a x this height is T 1 — — — j g, or g>— < ~, or, since h becomes ag HTDTiAFLIC INVESTIGATIONS. 117 -— , gf-— 2 hf so tliat h is always equal to half the difference _- x between g and the actual height of the column above the given point, or to half the height of the point above the base of the column. If two values of x, with their corresponding heights, are given, as b and x, corresponding to c and d, and it is rer quired to find a; we have — - — : c: : — '■ — : d, dbx — dax b x , , . dbx — cb x b d x — ch zcox-r-coa, and a 32 — -— or — ~ -: . a X-—C ft a a x -rr- c x Thus if the height equivalent to the tension vary in the ratio of any power m of the diameter, so that, n being a small quantity, x m b (l + n) and d zz c (I + mn\9 — Sf ftc((l-J-n).(l + «u)-l) mn + n ' —rr _____^_ since the be ((l-f-w). (1 -f mn--(l + w) " ■*• r. • , b w+1 r, square ot n is evanescent, and — zs . ror example, b 5 if m s 4, — 35 — » and if tw — 2, & : a : : 3 : 2. a 4 IV. Of the Magnitude of a diverging Pulsation at different Point?. _ The demonstrations of Euler, Lagrange, and Bernoulli, Magnitude of respecting the propagation of sound, have determined, that a diverging the velocity of the actual motion of the individual particles different1 ** of an elastic fluid, when an impulse is transmitted through points. a conical pipe, or diyerges spherically from a centre, varies in the simple inverse ratjo of the distance from the yertex or centre, or in the inverse subduplicate ratio of the number of particles affected, as might naturally be inferred from the general law of the preservation of the ascending force or impetus, in all cases of the communication of motion be- tween .elastic bodies, or the particles of fluids of any kind. There is also another way of considering the subject, by Waves, which a similar conclusion may be formed respecting waves diverging from or converging to a centre. Suppose a straight wave 118 HYDRAULIC INVESTIGATIONS. wave to be reflected backwards and forwards in succession, by two vertical surfaces, perpendicular to the direction of its motion ; it is evident that in this and every other case of such reflections, the pressure against the opposite surfaces must be equal, otherwise the centre of inertia of the whole system of bodies concerned would be displaced by their mutual actions, which is contrary to the general laws of the properties of the centre of inertia. Now if, instead of one of the surfaces, we substitute two others, converging in a very acute angle, the wave will be elevated higher and Jiigher as it approaches the angle : and if its height be sup- posed to be every where in the inverse subdu plicate ratio of the distance of the converging surfaces, the magnitude of the pressure, reduced to the direction of the motion, will be precisely equal to that of the pressure on the single op- posite surface, which will not happen if the elevation vary inversely in the simple ratio of the distance, or in that of Jn tensity of the anv other power^han its square root. This mode of consir inversely Iruhe Bering the subject affords us therefore an additional reason eubduplicate for asserting, that in all transmissions of impulses through teii^affeaedr elastic bodies, or through gravitating fluids, the intensity of the impulse varies inversely in the subduplicate ratio of the extent of the parts affected at the same time; and the same reasoning may without doubt be applied to the case of an elastic tube. Waves crossing There is however a very singular exception, in the case of each other. waves crossing each other, to the general law of the pre- ' servation of ascending force, which appears to be almost sufficient to set aside the universal application of this law to the motions of fluids. It is confessedly demonstrable, that each of two waves, crossing each other in any direction, will preserve its motion and its elevation with respect to the sur- face of the fluid affected by the other wave, in the same manner as if that surface were plane : and, when the waves' cross each other nearly in the same d rection, both the height and the actual velocity of the particles being dou- bled, it is obvious, that the ascending force or impetus is also doubled, since the bulk of the matter concerned is only halved, whiie the square of the velocity is quadrupled; and supposing the double wave to be stopped by an obstacle, its magnitude HYDRAULIC INVESTIGATIONS, J ]Q Tpagnitude, at the moment of the greatest elevation, will be twice as great as that of a single wave in similar circumstan- ces, and the height, as well as the quantity of matter, will be doubled, so that either the actual or the potential height of the centre of gravity of the fluid seems to be essentially altered, whenever such an interference of waves takes place. This difficulty deserves the attentive consideration of those, who shall attempt to investigate either the most refined parts of hydraulics, or the metaphysical principles of the laws of motion. V. Of the Effect of a Contraction, advancing through a Canal. If we suppose the end of a rectangular horizontal canal, End of a rec- partly filled with water, to advance with a given velocity, Gonial velocit" less than that with which a wave naturally moves on partly filled the surface of the water, it may be shown, that a certain Wlthwatef ™~ f . vancing with a portion of the water will be carried forwards, with a surface given velocity. nearly horizontal, and that the extent of this portion will be determined, very nearly, by the difference of the spaces de- scribed, in any given time, by a wave, moving on the sur- face thus elevated, and by the movable end of the canal. The form of the anterior termination of this elevated por- tion, or wave, may vary, according to the degrees by which the motion may be supposed to have commenced; but whatever this form may be, it will cause an accelerative force, which is sufficient to impart successively to the portions of the fluid, along which it passes, a velocity equal to that of the movable end, so that the elevated surface of the parts in motion may remain nearly horizontal : and this pro- position will be the more accurately true, the smaller the velocity of the movable end may be. For, calling this ve- locity f, the original depth a, the increased depth .r, and the velocity of the anterior part of the wave y, we have, on the supposition that the extent of the wave is already become ay considerable, x ~ — v, taking the negative or positive sign y i according t$ the direction of the motion of the end; since the quantity of fluid, which before occupied a length ex- pressed HYDRAULIC INVESTIGATIONS. pressed by y, now occupies the length y + v; and putting av a *> x — z, z 21 — ■■ . The direction of the surface of the y "t" margin of the wave is indifferent to the calculation, and it is most convenient to suppose its inclination equal to half a right angle, so that the accelerating fprce, acting on any thin transverse vertical lamina, may be equal to its weight ; then the velocity y must be such, that while the inclined margin of the waye passes by each lamina, the lamina may acquire the velocity v by a force equal to its own weight; consequently the time of its passage must be equal to that in which a body acquires the velocity v, in falling through a height b, corresponding to that velocity: and this time is expressed by — ; but the space described by the margin of the wave is not exactly z, because the lamina in question has moved horizontally during its acceleration, through a space which must be equal to b ; the distance actually de? z + b Qb scribed will therefore be z -f b> and we have — =r=_ =— , z -*- y v + 6=i^'aW+6y — B»=il?!l+2fty,2f*+ ivy — v — * v av* v*, , — N» av% t?* v \. = Tb—Tw *m mm*- t& hni> m beins tbe prq* per coefficient, v 5g m V b> and v* = m%b, ~^r+ y^ — »»* (i" + le)' y' ~ m v (I + ie) ± * Vt and y + v ~ m v ( — + «)+t^« But wnen f is small, we may take y + , n -i ma \/ b . j ; v \ v nearly m V ■£ , and z = — -7-77-7 ~ *S C2 a $)» and ¥ 25 a 4- -/ (2 « b)t while the height of a fluid, in which the velocity would bey, is nearly a -f- £ >J (2 a b) : consequently, when the velocity v is at all considerable, y must be some- what greater than the velocity of a wave moving on the sur- face of the elevated fluid ; and probably the surface of the elevated HYDRAULIC INVESTIGATIONS. JO I elevated portion will not in this ca9e by perfectly "horizontal i but where v is small, y may be taken, without material er- x y—-v z it S3 m d, and, calling a — c, e, m*/-^-c + mdz — me v' v b, />*=/— V (/-^): anc*in ^e 9ame planner /is |g$ HYDRAULIC INVESTIGATIONS. c^il e \/ ft /is found, for the second case, equal to -tt-~ f - — - — . d* (y + w) d For example, suppose the height a 2 feet, 6 r {, c z: 1, and consequently e — 1, then d becomes i, « r 4, and y := R ; and in the first case z rz *1, and in the second z tt •14. Varieties of If v, the velocity of the obstacle, were great in com pa- th e velocity a and open rison with m \/ -, the velocity of a wave, and the space c ifpco. below the obstacle were small, the anterior part of the ele- vation would advance with a velocity considerably greater than the natural velocity of the wave : but if the space be- low the obstacle b«re a considerable proportion to the whole height, the elevation z would be very small, since a mode- rate pressure would cause the fluid to flow back, with a suf- ficient velocity, to exhaust the greatest part of the accumu- lation, which would otherwise take place. Hence the ele- vation must always be less than that which is determined by the equation m \/ z c zz e v, and z is at most equal to ?a '— b ; but since the velocity of the anterior mar- V m cy *in of the wave can never materially exceed m \/ '-, espe- x cially when z is small, and and half the breadth c: then the force urging any thin vertical lamina in a horizon- tal direction will be to its weight as b to c ; and the space d, through which it moves horizontally, while half the wave passe* it, will be such that (c — d) . (a + ±b) — ac, when be eed ~ r. But the final velocity in this space is the 2a + b J r same as is due to a height equal to the space, reduced in the ratio of the force to the weight, that is, to the height -, and half this velocity is i m «/ ( j, which 2a + 0 \2c + by is the mean velocity of the lamina. In the mean time the wave describes the space c + d, and its velocity is greater c than that of the lamina in the ratio of ~ -f 1 to 1, that is a 2a + b\ la . . . /a \ - — ,— ■ — V 1 or -T- + 2 to 1, becoming m ( r + 1 ) b 124 MINERALOGY OF CHALANCHES. ~: T~7T — m ~7"/~^ — .~TT J which, when b vanishes, becomes 77? y* -, as in Lagvange^s theorem, and, when 6 is small, m{ >J - A . 1, or m * ; but if <*- \V 2 ^4 V (2a + b))' a/ (2«)' were small, it would approach to ?w \/ &, the velocity due to the whole height of the wave. V. ■A Mineralogical Descripti$n of the Mountain and Silver Mine of Chalanches, in the Department of the Istre^ By IIericailt be Thury, Mine Engineer*, Mountain of JL HE mountain of Chalanches, noted in the annals of mi- Chalanclies. neralogy for the variety and beauty of the mineral sub- stances met with in it, is now become celebrated in metal- lurgy, for the abundance and richness of its silver ores. Situation, and This mountain is in the vicinity of Allemont, in thp can? height. ton 0f pQisansf. It is above the confluence of the Olle and the Ilomanche, 2 myriam. [about 12 miles] east of Grenoble in a straight line. Its height, taken at the build- ings belonging to the silver mines, is 2159 niet. [2359 yards] above the level of the sea ; but some primitive peaks, stretching from south-east to north-west, rise 580 or 590 met. [635 or 645 yards] higher. Its loftiest summit is about 2750 met. [3005 yards]. Noticed by se- Many celebrated mineralogists have written on this moun- Teral, but im- ^j^ Schreiber, director of the practical school of Montr perfuctlv. ' Blanc, who superintended the working of the silver mines at Chalanches several years with great success, has published hi si * Abridged from the Journal des Mines, vol. XX, p. 41. •Y The canton of POisans is the richest country in Fiance with respect to its mineral substances. Its lofty mountains conceal ;i great number of vein;, the various and superb products of which are daily eiiricliiug out 1 collections. 6 St< many MINERALOGY OF CIIA.LANC11US. 1%$ many accurate and judicious observations on them in the Journal de Physique, but he has considered them merely "as silver mines. De Bournon, in his mineralogy of Dau- De BoumonV phiny, in the same Journal, has attempted to explain the ^^ncoiiSst- origin of its veins, and given a very ingenious theory for this em with fact*, purpose ; but unfortunately it is not applicable to the mine- rals of Chalanches. Dolomieu, Faujas de Saint-Fond, Dietrich, Mongez, Guettard, and others, have also spoken of this mountain, but no one has given a general view of its m; ,;ral substances. Before I enumerate and describe the various products Geological collected on the mountain of Chalanches, I shall give a *ketcl1 °* l%- geological sketch of it. It is of the primitive order, and composed of rocks, the base of some of which is simple, of others mixed. The latter are the most numerous, and con- stitute the chief mass of the mountain. The greater part of the veins yet known are found in a micaceous quartz rock, the strata of which dip in general to the south-west, but at an angle that frequently varies. The manner in which these rocks lie with respect to each other is pretty constant. Granite forms the base of the mountain, and is Granite. foliaceous. It frequently partakes of the nature of gneiss, Gneiss. sometimes of that of amphibolic rocks, and frequently of both at the same time. The gneiss and micaceous rocks vary as much in their grain and texture, as in the difference of their constituent elements. These rocks frequently al- ternate with amphibolic rocks ; often they are mixed toge- ther; and still more commonly their association presents itself with all the characters of a granite, in which the mica abounds but little. In some places the gneiss contains iron pyrites, and occasionally calcareous particles, the presence of which is easily discovered by means of nitric acid. The colour of the gneiss varies extraordinarily. Gray, yellow, green, white, black, &c, are its most common tints : but it is frequently of a red, or reddish colour, whence the rocks it forms have been termed burnt. About a third of the way up the mountain, and 800 met. Primitive limc- [874 yards] west of Traverse, the last hamlet we meet with st,nc' before we get into the wood of the mine, we see in the road tkree strata of nriauU?* limestone, whfch alternate with granitic, 126 Mineralogy of chalanches. FeMspar and gneiss with Granite with tourmalines. Secondary limestone. Bent strata. Summit. granitic, micaceous, and amphibolic rocks. These strata dip to the west at an angle of 60*. Their direction is north and south. This carbonate of lime is saccharoid, and emits a fetid smell when struck. Two of the three strata are a tolerably pure white; the third is gray with a rosy tinge, and adheres to the amphibole, that serves it as a wall. A little distance from this we find white feldspar rocks con- taining garnets; a little farther, gneiss with garnets; below, granitic rocks with tourmalines ; and lastly, proceeding down to Allemont, the proper position of the secondary limestone on the primitive rocks, Toward the summit of the mountain we see quartzoseand amphibolic rocks in strata that are bent, and turned back on themselves. Somelimes the doublings and redoublings are very numerous in the same mass. The summit of the mountain is schistose amphibofe veined with quartz. It is naked, and in part destroyed, having fallen down in irregular blocks of different sizes. The centre of the works is 1514 met. [1654 yards] above the confluence of the Romanche and Olle, or 2159 met. [2359 yards] above the level of the sea. The ores of Chalanches are disposed in veins, beds, and nodules; but these different modes are not continued on regularly. The veins are infinitely varied. Their magnitude, direc- tion, and inclination vary continually, and are subject to numerous accidents. These veins are in general placed one above another; they are sometimes very near together; they cross each other in every direction ; they preserve no regu- larity either in their course or dip ; they frequently proceed in a direction opposite to what they took at first ; lastly, they sometimes unite, and proceed together for a certain space, after which they separate, perhaps to unite again, or to disappear entirely, and with very different circumstances. The richness of the veins is not more constant than their mode of being. Frequently we find veins yielding 20 or 25 parts of silver in 100 of ore, which at a few decimetres [the dec. is near 4 inches Eng.] distance present nothing but a sterile gangue. Beds the same. The beds of ore are not so common as the veins ; they do not Height. Ore*. Veins very iiiegular. M1NEEAL0GY OF CHALANCHES. \Qf not continue for any considerable length ; and they expe- rience the same accidents. Their richness, direction, in- clination, thickness, &c, are continually varying. They are incessantly intersected, turned aside, choaked, and in- terrupted by the veins. Finally, as they appear to owe their formation to the same cause as produced and formed the veins after the rupture and convulsions of the mountain, and the filling up of its clefts, I am induced to consider them rather as horizontal veins, than as real beds. Sometimes the ore occurs in nodules, but less frequently Nodules* than in veins, and like these they vary both in richness and magnitude. Their gangue is still more varied. Most commonly it is Gangue very carbonate of lime, pure, mixed, associated, crystallized, yarious' amorphous, &c. Sometimes it is sulphate of lime; in other places it is flexible asbestus : frequently it is hyaline quartz, pure, mixed, crystallized, amorphous, &c. : occasionally it is argilaceo-calcareous : here it is green or brown pulveru- lent chrolite talc, and yonder the same in mass containing native silver: frequently it is epidote in mass or crystallized : &c. Among the metallic gangues we find oxide of cobalt Metallic gan- both earthy and vitreous, arsenicated, arsenical, and gray Sues» cobalt, all of them more or less argentiferous. Arsenical and carbonated nickel frequently perform the office of a gangue, and sometimes the first of these is even rich in sil- ver. Arsenic too is found in the argentiferous ores, but it is more rare than the preceding. Antimony occurs native, sulphuretted, oxided, and as a hidrosulphuret. Copper, which is very abundant in the veins, is met with in different states: pyritous, sulphuretted, oxided, and hidrosulphuret- ted. Gray copper ore is frequently found in the asbestus, and always very rich in silver. Iron and manganese, both in the state of oxide, occur very commonly in the veins at Chalanches: and the latter is even one of the richest gangues in silver. Lead is found as a sulphuret, and some- times phosphated. Mercury too is found in the gangues at y, &r Chalanches, and frequently is even abundant in them. Above the silver mines we find two narrow valleys, one o£ Valleys. which runs east, the other west. These narrow gradually to the foot of the highest peaks. The 1** MiNKRAtOG^ OP CH.UA^CHEl Anthracite. High ridge. Chalanches an iniartstym ob- ject of study. Sketch of its minerals. Hatty's 1st class. Carbonate of lime. Sulphate of lime. Sulphatfi of fcarytes. The western valley, called the CIos du Chevalier, exhi- bits an interesting object of study, a stratum of anthracite between strata of clay schist with vegetable impressions de- posited on a granitoid breccia. The latter immediately covers the primitive rocks cf gneiss or amphibole, that con- tain the veins of silver. Lastly, on the north of Chalanches is a sfh'nrp ridge, that joins the loftiest peaks of the great chain of Belledonne,- which extends from Vizille to Allevard as you ascend to- ward the high mountains of Maurienne. This chain is dis- tinguished for the number and variety of its rich metallic veins. The geology of the mountain of Chalanches offers us grand facts, and various subjects of observation with respect to the catastrophes, that have destroyed and overturned its primitive organization ; the violence it hat subsequently un- dergone; the number of its veins, their formation, and con* tinual changes; and the assemblage of so many various substances, separate or combined together, and modified in numberless ways. Of these substances I shall proceed to give a brief methodical sketch, arranged according to the four graud divisions of the system of Haiiy. In the first class, acidiferons earthy substances, we have" carbonate and sulphate oi lime. The carbonate is fre- quently found crystallized, and exhibits numerous varieties of form and colour. It is still more various in its combina- tions. Some of its compounds with iron and manganese have been wrought as sparry iron ore. It is mixed with magnesia in large irregular crystals disseminated through steatitic, asbestous, chloritic, and magnesian gangues. The sulphate has often been found in transparent crys- tals, sometimes coloured by copper, and lying on a silky amianthus, partly white, and partly rosecoloured from a mixture of pulverulent arseniate of cobalt. These are un- common, and varied in a pleasing manner. At "the foot of the mountain, toward Allemont, is a vein of sulphate of barytes, which was formerly explored in 6carch of sulphuret of lead, that appeared there to the day. It has some varieties of form and colour, being radiated, granular, compact, and white. Of HlKEfcALOGY OF CIIALANCHES. \Q() Of the second class, earthy substances not acidiferous, 2d diss, quartz is tolerably abundant. It has beeu remarked, that Quartz, its presence is a bad omen with regard to the richness of the silver ore* Its most usual combinations are with cobalt and antimony. The hyaline quartz is pretty frequent in the Rock crystal* veins, but rarely in well defined crystals: it is combined with a great variety of earthy substances, but its combina- tion with metals are still more numerous. Its compounds contain from two to five substances, and even more. Jasper is not common, but is sometimes met with in the Jasper, metallic veins, or those of quartz. Its varieties are brown, reddish, yellowish, and blackish. Garnets are very common in the rocks of white micaceous Garnets* feldspar, but they are very small, being at most 2 millim. [0*78 of a line] in diameter. Those that are found in the gneiss are larger, but less distinctly formed. They have not many varieties either of figure or colour. The veins produce some handsome varieties of feldspar, Feldspar. which is tolerably abundant in some parts of the mountain, and frequently in well defined crystals* Tourmalines are found in a rock of white micaceous feld- Tourmalines, spar, in tracing a Vein of sulphuret of lead at Lafare. They are in very distinct crystals several centimetres long, and about 1 cent. [3*9 lines] in diameter. They frequently oc- cur of a cylindroid figure in the heart of the solid rock. A few small veins of axinite associated with epidote are Violet schoerl. found in a hornblende rock at the foot of the mountain near the cascade of Batou* Epidote is very abundant in the veins, sometimes well Green schoerl, crystallized, and of a fine deep green, but very brittle. or PJsUcite* More frequently it is in mass, and sometimes constitutes whole rocks. Most commonly however it lines the sides of clefts in hornblende quartz rocks. Amphibole and actinote, which the analyses of Mr. Lau- Hornblende 8c gier have united into one species, are abundant, and form stranlilcin- masses of considerable bulk. At the bottom of the moun- tain, under the vein of Lafare, where a considerable por- tion of cliff fell down some years ago, there is a rock of white or gray feldspar, containing some beautiful needles of amphibole of a blackish green. This rock exhibits one Vol. XXII— -Feb. 180°. K of 130 An ore of tita- nium, and of magne- tic iton. Chrysolites. Mica. Asbestus. Amianthoid. Chlorite. Cd class. Sulphur. MINERALOGY OF CHALANCHES. of the most beautiful varieties of syenite granitello. TwO associations peculiar to the amphibole of Chalancbes are, 1, a calcareo-siliceous titanite in crystals of a lemon yellow, which form a pleasing contrast with the dark green of the amphibole in laminar masses : 2, a magnetic oxidule of iron in indeterminate crystals of a black metallic brown with a laminar fracture. Some veins of arseniated cobalt ore very rich in silver, and even frequently presenting this metal in its native state, contain a mixture of small greenish crystals, which might be taken at first sight for granulous epidote, but appear to me to be peridot. I could not observe any distinct figure in them : they are disseminated in small irregular grains amid arseniated or oxided cobalt ; frequently they are with sulphuretted silver; and sometimes they are covered with native silver. This mixture is one of the least common at Chalanches, but it is one of the most remarkable for the variety of its constituent substances, and its richness in sil- ver amounts to 18 or 20 hect. of metal in a myriagr. of ore [18 or 20 per cent]. Mica is very abundant in the rocks of Chalanches. It is in hexaedral laminae frequently very well defined ; and in colour white, yellow, gray, or blackish. The celebrity of the mines of Chalanches, and the appearance of the great quantity of silvery white mica in its cliffs and declivities, have led many persons but little versed in mineralogy to suppose, that the whole mountain was formed of silver. Asbestus is very common in the veins at Chalanches. It is found in different states, and modified by various mixtures. Frequently it is very rich in silver, and thrown into the fur- nace with the ore. The amianthoid of Chalanches is in fine, slender, silky needles, sometimes stiff and elastic, of a silky green co- lour. It is frequently tinged by oxide of iron, or of man- ganese. Chlorite talc is very abundant in the veins, both in com- pact masses and pulverulent; and in each state it frequently contains native silver. In the third class, combustible substances not metallic, there are only sulphur and anthracite. Sulphur is very common AlINERALOGY OF CHALANCHES. .131 common as a mineralizer, and has sometimes occurred na- tive in a whitish yellow powder. The anthracite is found Anthracite, foliated, scoriform, striated, and earthy; and is frequently traversed by small veins of quarts, exhibiting very pretty Crystallizations, that form a striking contrast with it* We now come to the fourth class, that of metallic sub- 4th class, stances. Gold has been reported to have been found atChalanches Gold, native, or alloyed with native silver, but this is erroneous. Mr. Schreiber hoivever, in his analysis of the copper pyrites of the vein of St. Lewis found it to be auriferous. Native silver is very abundant in the veins at Chalanches. Native silver. It has uever been found crystallized, but in various forms, as branchy, filamentous, capillary, lamellar, granulous, amorphous, pulverulent, and earthy. These eight varieties are mixed with a number of different substances, and in par- ticular with carbonate of lime, quartz, epidote, chlorite, pe- ridot, copper, arsenical nickel, carbonated nickel, earthy Oxide of cobalt, arseniated cobalt, oxide of iron, oxide of manganese, oxide of mercury, lead, antimony, &c. The native silver is found sometimes mixed with only one of these substances, at others with two or three of them, but more frequently with all of them together. Antimonial silver occurs very rarely. Antimonial Sulphuretted silver is very rare in well defined crystals : J?T"J* but it is found lamellar, filamentous, amorphous, and scori- silver. form, disseminated in the same gangues as the native silver, and with the same mixtures. Muriate of silver has never been found crystallized but Horn silver. once, when it was in a perfect cube, and the first time it had been noticed. It has since occurred frequently in a vio- let powder on the surface of native silver, or argentiferous cobalt ores; but it never forms more than a very thin coat on it. Sulphuret of silver and antimony is found occasionally in Sulphuret of small amorphous masses. Carbonate of lime tinged with Sllver and anti- . i « . , • mony, oxides of iron and manganese are its most common gan- gues. Beside these five states silver has frequently been found Argentiferous in sulphuret of lead, gray copper ore, arsenical nickel, &c.'; ore*' K 2 but 15% Mercury. Cinnabar. Galena. Carbonate of lead. Arseniated lead. Phosphated lead. Molybdate of lead. Gray copper ore. Cdpper py- rites. Carbonate of copper. Nickel. MINERALOGY OF CttALANCHfcS. but it is seldom if ever visible in these ores, and only to be detected by an assay. Mercury has been found here native but once. It was in a calcareous gangue, coloured by sulphuret of mercury and oxide of manganese. Sulphuret of mercury is very common among- the argen- tiferous ores. Frequently it is so concealed by the" oxides of iron, manganese, and cobalt, that it is only to be found by assaying. It occurs likewise with the sulphurets of zinc and lead, and some others. Sulphuret of lead is not abundant, but, when it does oc- cur, it is moft commonly very rich in silver. It is frequently iridescent. Carbonate of lead is very rare. It is found in the cavities of sulphuret of lead, quartz, and some argentiferous ores. It is seldom crystallized ; and when it is, it has the trihexae- dral form. Most commonly it is acicular, and sometimes earthy. Arseniated lead is found pulverulent or earthy in cavities of sulpheuret of lead. It is but rare. Phosphated lead sometimes occurs in small, fine, distinct fieedles of a yellowish green colour, on the surface of sul- phuretted lead that is full of hollows. Molybdate of lead was found by Schreiber at the foot of the mountain, near the cascade of Batou, after a great landslip. It is in a fine greenish schistous hornblende rock mixed with feldspar, intersected by small veins of green epidote, frequently crystallized in fine transparent needles. Among these needles the molybdate of lead is found. Gray copper ore is very abundant, but never crystallized. It is commonly very rich in silver; and among the combi- nations for which it appears to have a preference is that of silky asbestus. Pyritous copper sometimes constitutes veins of itself. A few of these were auriferous. Green carbonate of copper is frequent in the argentife- rous mixtures. It is commonly superficial, or as a colour- ing principle. Some of the veins have yielded fine and rich specimens of nickel, MINERALOGY OF CHALANCHES, 133 fiickd, in which silver has frequently formed more than one sixth of the mass. Arsenical nickel occurs very pure in -nodules, though Arsenical rarely. It is more frequently mixed with cobalt, iron, and silver. Frequently it contains silver enough to be worth working as an ore. This is a combination peculiar to Cha- lanches. Tt is in irregular nodules, of different sizes, capa- ble of being cut and polished. Oxide of nickel occurs frequently in fine specimens com- Oxide of monly covering arsenical nickel. It is white, or of a green mckel* more or less deep, and always pulverulent. Magnetic oxidulated iron is frequent in the hornblende Magnetic ox- rocks. It is in crystals of an indeterminate form, of a deep ' e ° iron* black colour, and with somewhat of a metallic lustre. Oligist iron is very abundant in some veins, is frequently Specular iron found in the strata of gneiss, and is common in those of ore* quartz, and carbonate of lime. Sulphuret of iron is not abundant, but sometimes occurs Pyrites, in the veins, and in the rocks. Occasionally it is without its yellow colour and metallic lustre, having acquired a dull and earthy aspect from decomposition. Oxided. iron is the most common gangue of the silver ore. Oxide of iron. {Sometimes the silver can be discerned in it by the naked eye; but it is more commonly concealed by the iron, which is more or less coloured and mixed with foreign matters. The sparry iron ore has been mentioned already under Iron spar. the head of carbonate of lime. Manganese is very abundant in the veins, but hitherto it Manganese. has been found only in the state of oxide. It accompanies the richest silver ores. Oxide of zinc occurs, though rarely. Sulphuretted zinc z'ma. is rather more common. Neither of them is crystallized. Arsenical cobalt is scarce, never forms veins alone, and Arsenical co- commoHly is destitute of silver. l' Gray cobalt is rather more common, but seldom pure. Gray cobalt. It is frequently mixed with arsenical nickel, and sometimes with silver. Black oxided cobalt is very abundant, sometimes pure, Black oxided but commonly mixed with oxides of iron and manganese, cobalt, sulphuret of mercury, and often silver. Arseniated 134 EFFF.CTS OF GRAVITY ON TIMEPIECES, Arseniated co- balt. Natireantimo- Sulphuret of antimony. Oxide of an- timony. Hidrosulphu- ret of antimo- ny. Arsenic. Titanium. Arseniated cobalt is met with in some veins, but never forms veins of itself. It pretty frequently indicates the proximity of veins of argentiferous oxide of iron. The ar- gentiferous earthy arseniate of cobalt at Allemont contains from 1 , 2, or 3 ten thousandth parts of silver to ten or twelve per cent. Native antimony is very rare at Chalancbes. It is in large or small shining metallic scales confusedly arranged, and forming masses capable of being divided parallel to the fa- ces both of a regular octaedron and a rhomboidal dodecae- dron. Sometimes it is in solid compact nodules capable of being cut and polished. The presence of arsenic, though in very small quantity, changes entirely the texture of the antimony. In this state it forms a kind of scales, the sur- face of which is frequently undulated. Sulphuretted antimony is found in the same situations as the preceding, but it is infinitely more scarce. It is prisma- tic or laminar, but more commonly amorphous. Oxided antimony occurs in rectangular crystalline lami- nae in the interior of the native antimony ; but more fre- quently pulverulent, white, and earthy, on the surface of the nodules with large facets. Hidrosulphuretted antimony is still more rare than the preceding species, but it is found with the oxide in the su- perficial cavities of the native antimony with large facets. Arsenic is never found native, but is sometimes combined with the nickel, cobalt, or antimony. The greenish or blackish amphibolic rocks frequently con- tain lemon-coloured crystals, which have been found to be a siliceo-calcareous ore of titanium. VI, Effects of Gravity on the Balance of a Watch compared with those on the Pendutym of a Clock, In a Letter from a Correspondent. To Mr. NICHOLSON. SIR, (a) JL Have been often led to compare the balance of the ▼ity on the ba- watch with the pendulum of the clock. The functions of both EFFECT5 OF GRAVITY ON TIMEPIECES. ] 35 both being to regulate the motion of the respective instru- lance hitherto ments, similar methods have been adopted in each for com- pensating the effects of heat and cold. But the difference of latitude which has been so fully recognized as affecting the pendulum has not yet, as far as I know, been considered to have any influence on the balance. (b) The time of the fall of the pendulum is in the inverse Gavity should subduplicate ratio of the force of gravity. In the watch, on motfo^oVa* the other hand, the time of the vibration of the pendulum watch, spring is in the direct subduplicate ratio of the weight of the balance. It appears to me, therefore, that any ap- proach toward the equator, by diminishing the gravity of the balance, must tend to accelerate the motion of the watch in the same ratio by which it retards that of the qjock. (c) Suppose the diminution of gravity at the equator T^ Difference of = 0*004367. Let the weight of a balance vibrating mean rate at the pole ; . & *> & the equator, time at the pole be denominated 1. Being removed to the equator, its weight will be 1 — 0*004367 rz 0*995633, and the time of one vibration at the pole, to the time of one vibration at the equator, will be as */ 1 to y 0*995633, or as 1 to 0*997814; consequently the number of vibrations in ope day at the equator will be to those at the pole as \ — 1*002191; which reduced to time eives 24b 3' 9*3". That is, the watch will go too fast 3' 9*3". If the diminution be taken at Tfa, agreeing with a printed table of the variation of the pendulum to every fifth degree of latitude, then by the same process, the errour of the watch will be 3' 48*3" daily. (d) The errour here is so great, that in proceeding from Experiments this latitude to the line, it is not possible, that it could have with the Pen* escaped observation, with the almost numberless experi- jUffumf S10U ments that are now made with watches; but if the reasons those with thf for the variation of the balance be found just, these experir balanc*- ments will stand in opposition to those that have been made with the pendulum. With respect to the latter, they have been conducted by men of such eminence, that we should have no reason to doubt their accuracy, if they did not dif- fer so widely from one another. (*) Mr. Richer found by experiments, that a pendulum, which 136 EFFECTS OF GRAVITY ON TIMEPIECES. Experiments which vibrated seconds at Paris, required to be shortened a dulum dcTnot ^ne anc* a 9uarter at Cayenne, four degrees from the equa-r agree. tor. Mr. Couplet the younger observed, that a pendulum, which swings seconds at Paris, must be shortened 2§ lines somewhere in Portugal, which is more than Sir Isaac New- ton allowed from the pole to the equator. Messrs Picart and de la Hire found the length of the pendulum, which beats seconds, the same at Bayopne, at Paris, and at Urani- bourg in Denmark. Mr. Cassini pretended to prove from experiments, that the polar diameter is the longest. In short, conclusions can hardly differ more widely. (f) It may be thought, that a decrease of gravity will not have the same effect as lessening the weight of a balance. I suppose gravity constitutes weight. They decrease and va~ nish together. It is the inertia of the balance, that regu- lates the vibrations of the spring; but its inertia arises from its weight. They decrease and vanish together. I do not mean however to assert, that there is no variation of gravity in different latitudes. I only suspect, that it is considerably ]e6s than the received opinion allots to it, and that it is pro-? bably irregular. The centrifugal force about the equator is a principle evidently tending to lessen the effect of gravity; but the internal structure of the Earth, of which we know nothing, may lessen or vary its effect. Experiments {g) Those who have inclination and opportunity to make with the pen- experitnents or observations on this subject will have no oc- dulum and ba- r ■ ■ J lance may be casion in the first instance to go any great distance. Two degrees about this latitude, according to the table, produce not less than 7§" per day of errour in the pendulum; and if the balance be found as accurate a measure of the varia- tion of gravity as the pendulum by operating the contrary way, there will arise a difference between them of 15" per day; a quantity very discernible. Many watches are to be found, that do not vary in their daily rate so much as 7f" for a considerable time, and clocks not nearly so much. Portable pen- (A) A pendulum rod might be made more portable, by dulum rod in ^eing 'm three pieces to join together with perfect accuracy, and consequently not subject to be bent, by which the length would be altered; and the ball being also fixed fast, and the time of the vibration ascertained in some latitude, it made within 150 miles. different pieces. EFFECTS OP GRAVITY ON TIMEPIECES. \§J it might be taken in pieces, and when reconstructed else- where the difference of time would show the length requi- site more correctly than any other sort of measurement, and consequently the difference of gravity. Several little er- rours would be avoided by always using the same pendulum. (i) Mr. Cumming, in his Elements of Clock and Watch Vibrations of a Work (notes to Article 410) says, « In the pendulum, gra- ^pTndot gT. «' vity is the motive force ; and in the balance the spring : vity. " the vis insita is the resistance in each ; and the contrary: *' therefore, when the motive force is in each as the resist- " ance, the velocities and times must be equal. Hence it ** also happens, that (c. p.) the balance measures the same " time in all latitudes." And afterward : " Here by alter- " ing the weight, is strictly meant, altering the vis inertice; " for the vibrations of a balance, whose centre of gravity " coincides with its centre of motion, have not the least M dependence on gravitation, otherwise it would alter iti *f times in different latitudes as well as the pendulum." (k) Here it appears to me, that Mr. Gumming considers the vis insita and vis inertia? of matter, as powers wholly in- dependent of its gravitation or weight. I suppose it will not be doubted, that a balance becomes heavier or lighter, as gravity is greater or less, and if hung by its spring, it will stretch the spring proportionally to the power of gra- vity: still he considers its vis insita to remain unaltered with its motive force, and consequently that it will measure the same time in all latitudes. (/) I think it is generally allowed, that the vis inertias is vis inertix. proportional to the quantity of matter. We distinguish a greater or less quantity of matter by its weight, consequently its vis inertiae will be proportional to its weight, for it is cer- . tain that any thing heavy has more resistance than a thing that is lighter. (m) Suppose a watch vibrating with a steel balance, and, Balances of without any other alteration, let it be taken off and replaced dlfferent J .i ' . . weights require with a gold balance of equal magnitude in every way, which, springs of dit- for convenience we shall suppose to be just double in weight. ferent Though in this case nothing is altered but the weight, the in- ertia is just doubled, for it will require another spring equally strong, added to the former, to give it the same velocity. (n) Again ]38 EFFECTS OF GRAVITY ON TIMEPIECES. Enlarging a ba- («) Again, every thing remaining as before ; suppose I beat mUar effect!1" out tllis &old balance ^Xi its diameter be just doubled, or, more accurately, till its diameter of percussion is just dou- ble: here the inertia is quadrupled, for now it will require eight springs equally strong with the first to make it vibrate in the same time, and, generally* let D be the diameter of percussion, and W the weight, the power of any balance will always be as D*xW, for the strength of the spring must be in this proportion to make it vibrate in the same time. If the number of vibrations are changed, that is more or less in the minute, the velocity in similar parts of each vibration will be as this number, and if it be denoted by N, the power of any balance will be as N* x £>* X W, the spring being in this proportion. (o) Mr. dimming goes on to say, that " the vibrations of a «« balance, whose centre of gravity coincides with its centre ** of motion, have not the least dependence on gravitation.*' Surely this cannot mean, that balances of different weights, having their spring or motive force the same, will vibrate in equal time; but either this must be the case, or he must consider a variation in the power of gravity as not altering the weight of any thing. Variations of ip) * nave neard ** remarked, that timekeepers do not go timekeepers so well at sea as they are found to do on land. But as all considerable changes of place are made by sea, it is possi- ble, that the influence of latitude on gravitation may be the unsuspected cause of some part at least of this deviation. If the principle I have suggested be not erroneous, it will be of more importance than ever, to ascertain the exact variation of this influence. But as I am veiy conscious, that my attainments in science are not such as to entitle me to be positive in a matt* r of this magnitude, however plain it may appear to my own mind, I am solicitous to be fa- voured with your judgment upon it, or that of any of your correspondents. I am, Sir, Your most obedient humble servant, X. ANNO- at sea. ARTIFICIAL CHELTENHAM WATER. 1 39 ANNOTATION. We assert, that the gravity of a body, is as its mass, and Iner'ia ccm^i- fhat its mass is as its inertia, or the power by which it tends ria^e< to preserve its state as to motion. Admitting or assuming the inertia to be invariable, we deduce, that gravitation va- ries inversely as the square of the distance between gravi- tating bodies; and our observations on the relative situations and motions of the heavenly bodies show, that this is the case; or else, that, if the inertia be subject to variation, its changes are such as to produce, along with some correspon- dent opposite change in gravity, a result of the same kind, as was accounted for on the supposition that the inertia does not vary. But we seem to have no decisive facts to deter- But decisive mine as to our original hypotheses, and therefore prefer the fa^ts are want" simplest. Though the author of the preceding letter ap- pears to have confounded the terms gravity and inertia; yet the experimental speculation, to which his letter points, ap- pears to be of sufficient interest to lead to meditations of so that there is some value, and to authorize its insertion in our Journal. ™°™ for m~ W. N. VII. j4n Account of a simple and economical Method of preparing an artificial Cheltenham Water highly impregnated with Carbonic Acid (fixed Air). By Richard Greene, Esq. pfCork, A.B. Trin. Col. Dub., M.D., and President of the Royal Medical Society Edinburgh. To Mr. NICHOLSON. SIR, I F vou think the following communication merits a place „, , i ii t I*- e .i * • , Cheltenham in your valuable Journal, it is periectly at your service, and water of high ]by its insertion you will confer an obligation on repute. Your most obedient humble servant, Edinburgh, Dec, 27, 1808, R. G. The purgatiye and chalybeate waters of Cheltenham have long and deservedly been celebrated, in the cure of many obstinate and alarming diseases. The chief obstacles to their more general employment seem To be, the impossibi- lity 140 ARTIFICIAL CHELTENHAM WATER. lity of procuring the natural water in a proper State except at the spring; or the scarcity and exorbitant price of the aerated artificial imitation, which too is very seldom to be met with properly prepared. The carbonic The simple solution of the saline matter of these waters ^anmportance is often Prescribed witn tne most happy effects. This, how- i»it. ever, entirely wants one very active and important ingre- dient of the natural water, the carbonic acid; by the lively pungency of which, when in sufficient quantity, the offen- sive taste of the salts is concealed, and a nauseous medicine is converted into an agreeable beverage. This is only one, and perhaps the least of the advantages of the carbonic acid. By virtue of it, and the iron which it holds in solution, the use of this water may be persevered in for a long time with- out inconvenience: for during its employment the appetite will be improved, and the digestive organs strengthened : The more of and the greater quantity of this acid the water can be made this it contains to contain, the less offensive will it be to the palate, and the tli€ better less it will be liable to be rejected by the stomach, while the whole system, sympathizing with the tonic effects it pro-? duces on that organ, will be the more speedily invigorated. Us chief uses, ^ would be out of place here, to enter largely into the medicinal properties of this water*, I shall just enumerate- the principal affections of the system, in which it has been found particularly useful. Those, whose biliary organs a long residence in a warm climate has impaired, seldom fail to receive much benefit from a course of Cheltenham water, and its use may be continued even under circumstances of great debility : and will be emimently serviceable if any symptoms of dropsy or anasarca threaten, as so often hap«r pens in affections of the liver. In glandular obstructions its use has often been attended with success. In all cases where the secretion of bile is vitiated, or irregular; and in jaun- dice from resistance to a free discharge from the gall blad-> der, attended with sense of heat and distention after eating, this water will be employed with particular advantage. For removing a sense of fulness about the head in the plethoric, and for carrying oft' the effects of any excess in eating or • See Dr. Saunders's Treatise on Mineral Waters, 1805. drinking ARTIFICIAL CHELTENHAM WATER. 141 drinking, no medicine seems more proper than this laxative diluent. For habitual constipation of the bowels, as the stimulus of this water is so slight that its frequent repetition cannot be productive of injury, it may be considered the safest as certainly it is the most pleasant remedy. From the many valuable properties of this mineral water, An artificial I am firmly persuaded, that it would be far more exten- water' et*.ual ,f J l . ' . i • . not suPerior to sively employed than it is at present, if it were possible to the natural, convey the natural water to a distance unimpaired, or to easi1)' prepared. procure at a reasonable price an imitation of it, that could be relied upon. I therefore trust, it may not be altogether useless, to lay before the public a simple and economical method, by which any person may in a few minutes pre- pare a water eminently possessing the virtues of the natural spring, as composed of the same ingredients, but more palatable, as containing a larger quantity of the carbonic acid, which also increases its tonic powers. The natural Cheltenham water owes its virtues principally Ingredients of to the sulphates of soda and magnesia ( vitriol ate d natron, ter<]nd ura wa" and vitriolated magnesiaj which are its purgative consti- tuents. It contains also about one eighth of its bulk of carbonic acid, which holds in solution nearly rive grains of iron in each gallon of the water. The sulphate and carbo- nate of lime, which may also be detected in it, are not likely in any respect to influence its medicinal properties. The carbonic acid employed in preparing artificial mine- Impregnation ral waters is obtained by decomposing: the natural carbonates of wat<;r wit^ j, iii.T n carbonic acid. ot lime ( marble or chalk J, by means of the sulphuric (vitri- olic) acid, which disengages the carbonic, in its elastic form, to be afterward forced into the water by mechanical pressure, and apparatus which has not yet been disclosed to the public. The carbonates of soda and magnesia (common soda' or Carbonates of prepared natron, and magnesia alba) contain a largre pro- tlle bases in c , , l-j i • • , ., Cheltenham portion ot condensed or combined carbonic acid essential to water give out their constitution; the former about one sixth, and the lat- this acid whett ter nearly half its weight. They likewise are both decom- comp^the posed by a proper quantity of the sulphuric acid, which, neutral salts in uniting to their bases the soda and magnesia, forms the sul- lt' phates of these bases, or the salts of Cheltenham water ; the carbonic acid escaping with effervescence in its aeriform state. It 142 ARTIFICIAL CHELTENHAM WATElt. and this may It occurred to me, that if by any means this gas ceroid be retained in be confined at its first disengagement, and a sufficient quantity of water present, it would be absorbed by that very water in which it would be disengaged, and serve the same purpose as when afterward driven into it by the force of a condensing apparatus* I made many experiments to this effect, with different proportions, and with different quanti- ties of the ingredients, and with the most satisfactory re- sults: and found, that the entire process could be safely and Id a common conveniently conducted, in a pint, or half pint bottle of ixnerkneiit comuio>1 green glass. Having calculated what quantity of proving this, the carbonates of soda and magnesia (properly propor- tioned J would yield on decomposition a volume of carbonic acid, that might without danger be confined in a half pint bottle; I found the quantity of dilute sulphuric acid neces- sary to decompose it, and measured it out in a graduated glass. I then put the carbonates into the bottle, together with one grain of the sulphate of iron f green vitriol) ', and nearly filled it with cold water; just leaving room to add the sulphuric acid, which 1 next put in, and instantly closed the bottle, securing the cork with a string. By a little agi- tation, the salts were soon dissolved, and the liquor became transparent : and on removing the cork, I had the satisfac- tion to find the process had succeeded equal to my most sanguine expectations: for the lkiuor was so highly impreg- nated with the gas, as to be scarcely distinguishable in taste from the best prepared soda water, and it flowed with ebul- lition from the bottle, the instant the string was untied, driving out the cork with considerable violence. The quan- tities here employed were too great for general use, being nearly one half greater than the proportions, which farther experience has enabled me to recommend: however, they tshow, that the strength of the water may be much increased without bursting the bottles. Farther particulars of the process, and cautions to be ob- served in conducting it. The carbonate of soda employed was the common soda of kuig Cnel- commerce, that prepared from the muriate of soda (sea tenham water. ^. ^ ^ patent process, which neither deliquesced nor effloresced by exposure to the air; and by a very delicate test Process for ma ARTIFICIAL CHELTENHAM WATER. 143 test gave no indication of the presence of lead, which has been suspected to be contained in soda manufactured in this way. The quantity I would recommend is two scruples, or forty grains troy, for the half pint of water. The carbo- nate of magnesia I made use of I prepared myself from sea water, and therefore I could depend upon its purity. The quantity for the same dose of water is one scruple, or twenty grains: the half of the quantity of the soda. The sulphuric acid I employ is the dilute acid of the Edinburgh College; of the specific gravity of 1-0735, and was formed, by adding one' part (by weight) of the strong acid of com- merce, of the specific gravity of 1*852, to eight parts of water. The quantity of this acid I use is 250 grains by measure, or a quantity equal in bulk to 250 grains of water. In this proportion, there is a slight deficiency of sulphuric acid, which should always be observed ; for the excess of carbonic acid will be able to dissolve any carbonate of mag- nesia that may remain, and any excess of sulphuric acid gives the water a harsh disagreeable taste, and might injure the teeth, or affect the bowels, if irritable. The volume of carbonic acid gas disengaged by these quantities is about 35 cubic inches, and in a half pint bottle is equal to the active pressure of an additional atmosphere and a half on the sides of the bottle, or to two atmospheres and a half upon the surface of the water. The sulphuric acid is best to be di- luted, as by this any errour in measuring will be diminished, and by dilution it throws down a sediment, which often con- tains a portion of lead. As the carbonate of soda is unsteady in the quantity of Indication of water it contains, being affected by the dryness or humidity d "ficiency °{ of the atmosphere, and the sulphuric acid of commerce is not always of the same strength, it may happen, that the quantity of the acid I have here specified shall not exactly answer : if so, any excess will manifest itself by an acid taste in the water after it has stood some time exposed to the air in an open vessel; and any great deficiency of acid, by the whole of the magnesia not being dissolved. In this case the quantity of acid must be increased or diminished as indicated. But I would advise every person, who would The proper wish to give this process a fair trial, to appreciate by expe- £ggJ>ortlons . riment J j4 ARTIFICIAL CHELTENHAM WATER* ed by an easy rim en t the quantity of acid required for the soda and mag'-' experiment. nesia he may employ; as it is very simple, and easily per- formed. Weigh out the proper quantity of the carbonates, and put them into a common wine Or ale glass, with about ' an ounce of water; add gradually the acid to them, con- stantly stirring them until they are dissolved, and all eifer- vescence has ceased ; taking care, that no excess be employed, which may be known by the acid taste, or by turning to a red the natural blue vegetable colours, (as infusion of lit- mus, or of red cabbage leaves in hot water) ; note exactly the quantity of acid that was used, and make a measure containing ten drops less than that quantity, which is easily done by marking a slender ounce phial or glass tube, by means of a tile, or a diamond. If this is found to answer well, a good parcel of the same ingredients as those of the experiment should be procured and kept in close vessels. Farther pre- The cor^9 should be previously fitted to the bottles in cautions, . ... • which the artificial water is to be prepared, that no time may be lost after putting in the acid ; and the bottles should always be kept on their sides, that the liquor may cover the corks, and thus prevent the escape of the gas. The mag- nesia should be in fine powder, that it may dissolve more readily : the soda is best not to be so, as by itsslotv solution* the magnesia will meet the acid in a more active state, and there is no danger, that the soda will not dissolve readily enough. By minding these precautions, a bottle of the wa- ter may be made ready for use in less than a minute: but it will keep very well, only observing to shake the bottle be- fore opening it, as the iron precipitates in part. Strengthofthe The strength of the water may be varied at pleasure, br water may be ° . . m. * varied. altering the quantities or the salts with respect to the water, but mijnding the relative proportion of the acid to the car- General pro- bonates. For a pint bottle the quantities are: carbonate of price?11* an soda four scruples, or eighty grains; carbonate of magne- sia two scruples, or forty grains; sulphuret of iron two grains. This is a full dose for an adult, and more than should be taken for a constancy, during a course of this wa- ter. The expense of preparing a pint bottle is about one penny; the strong sulphuric acid or oil of vitroil, is only eight pence per pound, and the soda the same price, or nine pence, by the single pound. VIII. ON GAS LIGHTS. % |j VIII. Second Letter on the Advantages of Coal Gas Lights, By Mr. B. Cook. To Mr. NICHOLSON. SIR, AN my last letter I promised you a few plain drawings, but On the advarw I have been out of Town nearly three months since I wrote f?S«* of 8as to you, which has hindered me from sending them. I am desirous, however, if possible, to hand you the few following ' remarks, in addition to my last letter, in time for your Jour- nal. First, with respect to oil and cotton, the man who does Where no sol- not use these articles, may unthinkingly strike that out of a^"rg| 1S re" the statement, and then there appears but little or no ad- vantage from the adoption of the use of the gas lights. But he must not do this: for, if he do not use these arti- cles, a large portion of the expense in the execution of the apparatus is saved, and one lamp will consume as much gas as nearly twelve lights, or candles. If this is duly consi- dered, the saving is the same, or nearly so; for less gas will be wanting to be made, less coal consumed, and the man or boy, that makes the gas, will perhaps be required to make it only two or three times a week, instead of every day, which will be the case, if the gasometer is small and lamps used. Instead therefore of employing a man a part of his time at five shillings per week, a boy will be employed to do it at perhaps two shillings per week or less. Indeed in most manufactories a boy or an old man is kept to job, or go on errands; and he will be able to do this and all his other jobs besides; so that in most manufactories this man, which forms a very great portion of the expense, may be entirely struck out. Besides, the industrious man, who works in his own shop, may do it himself, as the trouble is little, only putting a fire under the retort, and filling there- tort with coal ; when it will require no farther attention, ex- cept to see now and then that the fire is kept up. Vol. XXII.— -Feb, I809. L Secondly, U6 ON CAS LIGHTS. Leaden pipes preferable to old gun bar- rels. Secondly, I recommend the use of old gun barrels for pipes: but since I wrote my former letter, I have been in- duced in a great measure to change my mind ; for, having been employed in putting up the apparatus for some per- sons in this place, I find the promised advantage is not so great as it first appears. Being in short lengths, they re- quire many joints, or soldering places, and if they be not properly sound and air-tight, the gas escapes, a disagreea- ble smell is produced, your gas is wasted, and the process is disliked. Now the patent lead pipe may be had in lengths of fifteen or twenty feet, so that even in extensive manufac- tories but few joints will be wanting. The pipes likewise can be made three quarters of an inch or one inch in the bore or hole, which is an advantage; you can bend them round any angles ; and there will not be so great a proba- bility of leakage, when there are but few joints. I think therefore, although the lead pipes will be rather more ex- pensive, yet when all their advantages are considered, it will be better to adopt them, than the other. Besides, when the pipes are done with, and a man gives over trade, or when he removes his manufactory, he can very easily remove these and put them up again, or sell them for a great part of the original cost for old lead. There is also another saving in the workman's putting up the apparatus, as he puts up the lead pipes in half the time he would the old gun barrels. Perhaps therefore we may make the following statement, for in fact it will be in general the true statement, where only lights are wanting for twenty weeks in the year. Dr. Cr. Corrected statement. Coal for twenty weeks, at Is. 3d I 5 0 Interest on £20 or 25 ..•• 1 5 0 Saved 16 2 6 £18 12 6 Twenty weeks, at is.Sd, 18 0 0 Coak 0 12 6 £18 12 6 Here I have only allowed the half of my former statement for the expense of coal, supposing no soldering is done, for in that *>N GAS tIGHTS. 147 thaf case not half will be used, and twice or three times a week will be quite sufficient for making the gas. I have also left out entirely the expenses of a man, as this will be seen to be quite unnecessary, so little time will be required to make and attend it, if only used for lights. The apparatus too in this case will not cost more than twenty or twenty-five pounds, so that I have allowed only one pound live shillings for interest. And although I have reckoned only twenty candles to be used in this statement, and have calculated therefore on the saving of twenty; yet twenty-five, or even more may be lighted, and at a very lit- tle additional expense, as it can only be in a little more coal being consumed ; so that, if I were to reckon, that twenty- five or thirty candles were used, you see what a flattering advantage would appear. But I am not desirous of paint- ing the picture with glaring colours, the saving in this state- ment is sufficient to satisfy every mau, who is interested in it, of the great utility of the thing. There is one thing more I would advance in its favour. It Its disagreeable has been objected to by several, on occount of its disagreea- sme!1 no* ble smell if any of the gas escape, or if the gas have not Hbeen properly purified. Now, Sir, the very thing they ob- ject to is an advantage. I would ask any medical man, whe- ther the smell of burnt tar be injurious to the constitution. Why burn pitch and tar, to destroy contagion, if they have not the power of doing it,? The gas will be found, instead but conducive of destroying health, to promote it, even in the last stages to health. of consumption. It is a fac;t, the smoak of the coal fires in all large manufacturing town^, instead of injuring the health of the inhabitants, is goodfoivit; for the contagious diseases are hardly ever known to appear, much less to increase ii| them. And how can we account for the prevention of these diseases, and for their not making sad havoc and devastation, in places, to all appearance so well calculated for their seat; crowded manufactories, crowded streets, filthy drunken workmen, the whole town at times quite enveloped with smoke ; if we do not attribute it to its real and true cause, the coal smoke ? The introduction of the gas into manufactories will be found still more useful and beneficial, as it will destroy the L 2 inconvenience 148 PLATINA SPRINGS FOR tVATCHRS. inconvenience so often complained of in crowded shops ami manufactories, where so many people are forced to breathe the same air over and over again, and which really is injurious to a very great degree. I say it will remedy this by purify- ing the air. I have no doubt it will completely hinder any thing like fever from spreading in those shops and manufac- tories, if it should be accidentally introduced. In fact it will be found to purge and purify the air, and to promote health, instead of injuring it. I am, Sir, Your humble servant, B. COO&. Caroline-street, Birmingham, Dec. 27 th, 1808. IX. On the Superiority of Platina for making the Pendulum Spring of Watches. By Mr. James Scott. To Mr. NICHOLSON. SIR, Balance spring -OlS your valuable Journal is universally esteemed a source capable of im- 0f tne best information and most general utility to the me- chanical as well as the philosophical world, I beg leave to trouble you to insert a few remarks on the subject of the pendulum spring, as it is a part of watch work I have often considered capable of the greatest improvement. Platina the * nave keen l°nS C0I>vinced of the superior advantages of best material, platina over any other metal of which this instrument has hitherto been made, but I have not until lately been able to procure any of it in wire fit for that purpose. I find it by repeated experiments to possess great superiority on account but arsenic °^ 'ts inperceptible expansion ; and, what is worthy of re- must not be mark, the platina procured for this purpose should not be consiwalin1 consolidated by arsenic, as it is by that means liable to ex- it, pansion. I also find it, when properly drawn, to possess sufficient elasticity for any extent of vibration ; it coils ex- tremely well ; and, if placed when coiled on the surface of a flat piece of metal, making one end of the spring fast, and marking exactly the other extremity, the slightest expansion T CONSTRUCTION OF GALVANIC BATTERIES. J^Q is not visible when applied to heat : so that if these springs are judiciously made of this metal, I am convinced they will turn out a general benefit to the public, which is the princi- pal object of, Sir, Your much obliged and obedient servant, 39, Grafton-street, Dublin, JAMES SCOTT. June 20fA, 1808. P. S. Having for a length of time made use of this metal Superior to in my compensation curbs, I consider it as very superior to st*ng*?r com" •teei for every instrument of this kind. curbs. N. B. This paper would have appeared much earlier, had it not been accidentally mislaid. % On the Construction of Galvanic Batteries. In a Letter from a Correspondent, To Mr. NICHOLSON. SIR, JtLVERY lover of science in the country must have felt Queries re- the great advantage of a philosophical Journal, in which he sPectmg *he & • i • i- • i-i-i construction of never fails to meet with a judicious selection of the most galvanic batte- important discoveries, and whence he may hope to derive ries* information, that would be vainly sought after in any regular treatise. Some friends, who have united their efforts to follow Pro- fessor Davy in his grand experiments on the decomposition of the alkalis, would feel highly gratified by replies to the following questionso What is the smallest number of Galvanic combinations, and the smallest surface of plates, that is sufficient to de- compose the fixed alkalis? And, what is tlje best solution for charging a battery, so as to produce the greatest power? We have seen, that batteries formed of the common rolled zinc do not act so powerfully as those, which have been made with zinc plates that were cast, It is suid, that sine is commonly alloyed, to make it roll the easier; but it it 130 CONSTRUCTION OF GAtV.ANIC BATTERIES. is certain, that it may be rolled much thiner than is requir- ed for this purpose, in its pure state*. I am, Sir, Your obedient servant, Jan. 2<*, I809. G. K. M. REPLY. Having taken the liberty of troubling Mr. Davy with a line on the subject here stated, I was favoured with his an- swer, from which I extract the following. Battery capa* M In my early experiments upon potassium, I often pro- bleof decom- Cure(j ft by means of a battery of one thousand pairs of posing potash. . *■ plates of copper and zinc of six inches square, charged with a solution of concentrated nitrous acid in about forty parts of water. This is the lowest power that I employed : but as some of the plates had been much corroded by former processes, I should conceive, that a combination of eighty would be sufficient, provided the whole arrangement was perfect. Less power " The decomposition of the alkaline earths and ammonia sufficient for by amalgamation or combination of their bases may be ac- ammonia! complished by a much weaker combination, fifty plates of six or four inches square being adequate to produce sensi- ble results. Potassium may " The potassium, which I have used in various analytical be procured enquiries lately carried on, has been ail procured by chemi- withoutelec- * .. ,',..«,■•,,■ tricity. cal means, without the application or electricity. " Potash may be decomposed by different processes, some of which are described in a paper, which I am now reading before the Royal Society; but the best method is that, which we owe to the ingenious researches of Messrs. Gay Lussac and Thenard, and which is the first of this kind, by mere chemical attraction, made known. Chemical de- « When melted potash is slowly brought into contact with of 3ush°n *ron tunungs> or filings heated to whiteness, hidrogen gas is evolved, holding potassium in solution • and if one part of the iron tube, or gun barrel, in which the experiment is made, be preserved cool, the metal is deposited in this part, being precipitated from the hidrogen gas by cooling. • And at the common temperature. 1$. « The \ UKW EVAPORATING HOUSE FOR. SALT WORKS, |£ J " The potassium is never procured quite so pure in this Near 100 manner, as by electricity; but it is lit for analytical pur- ^ass Procured poses, and I have obtained it with so little alloy, as to pos- by one opera-f sess a specific gravity considerably below 8, water being 10. tlon' I have now by me a compact mass produced in an operation which weighs nearly 100 grains." XI. Account of an economical Method of Evaporating the Water of Brinesprings, employed at the Salt Works of MoHtiers, in the Department of Mont-Blanc. By Mr. H. Lelivec, Engineer of Mines, Sfc. for the Departments of Mont-Blanc and the Leman Lake*. JL HE richest spring at Moutiers is constantly at the tem- Brinesprings at perature of 30° R. [99*5° F.], and when cooled dowu to 10° Moutiers. [54*5°] indicates on the areometer r83°f. The poorest raises the thermometer to 25° [88° F.] only, and indicates \'5° of saltness. The water is conveyed by troughs to a large re- Method of servoir, where it is left to settle ; and thence it passes through Procurir ff the , , i • , i ii salt from them, other troughs to graduation nouses about 1100 yards, lower down. In its course it gives out bubbles of carbonic acid gas, and deposits a reddish sediment, which is at first oxide of iron, then a mixture of this with carbonate of lime, and at length almost wholly calcareous carbonate. It passes through four graduation houses in succession, and comes out of the last at the strength of 18°, and sometimes more. It is then boiled for about six and twenty hours, or till the salt begins to crystallize, keeping ti.e boilers constantly full; a foulness, that rises, is scummed off; and the sulphate of lime it contains is precipitated. The sulphate of lime being raked out, in winter the eva- poration is continued, with a slow fire, till the whole of the salt is deposited : but in summer a different process is foU lowed, by which all the fuel consumed in the last stage of * Journal des Mines, No. 120. •f The areometer commonly employed in the French salt works is di- ' vided into 50 degrevs, beginning at distilled water, and ending at water ' saturated frith salt. the 152 NEW EVAPORATING HOUSE FOR SALT WORKS. 2*ew method the process is saved. When the solution is brought to the the ?alt with-gP°^nt °^ saturati°n, it is conveyed to a reservoir, whence it out fire, is raised by a chain-pump to a trough at the top of a wooden building, and extended its whole length. From this trough it runs into a series of very narrow troughs at right angles to it, and about two yards long, To each of these are twenty-five double or endless roves, 6 millim. [2*4 lines] in diameter, 13 cent. [5 inches] from each other, and fixed 8 met. [26 feet] below. The saline water, flowing con- stantly out at notches cut in the sides of the troughs, trickle- down the ropes, round which it forms a very thin coat, displaying a considerable surface to the solvent power of the air. As the water evaporates, the salt is deposited on the ropes. The water that flows down runs into the reser- voir, and is pumped up again repeatedly, till it is exhausted, when it is suffered to run into the basin, that contains the mother- water. The water of a fresh boiling is treated in the same man- ner, and thus seventeen boilings are raised in succession, forming one making, which occupies forty or five and forty- days. At the expiration of this time the ropes are covered with a cylindrical coat of bait 7 or 8 cent. [2*75 or 3*15 in- ches] diameter, which is broken by a particular instrument for the purpose. As this process can be executed only in summer, seldom more than two making stake place in a year. Every boiling, before it reaches this building deposits 100 myriagr. [2205 lbs] of salt in the boilers; and 650 myr. [14332 lbs.] are collected from the ropes, making in all 750 myr. [16537 lbs.] This process therefore does not yield quite so much salt, as the product of the evaporation of a similar quantity of water by two boilings would be 786 myr, [17332 lbs.] ; but then there is a considerable saving of time and labour, as well as of fuel, and the salt obtained is more pure. This process, equally ingenious and economical, invented by Mr. Dubutet, has been employed with success ever since the year 1788. It has not yet been adopted in any other salt works. It would be particularly advantageous in hot and dry climates. It may be used Mr. Roche has enhanced the ulility of this building, by- employing Quantity of fcalt made. The process has been fol- lowed 20 years. ECLIPSES OF THE SATELLITES OF JUPITER. ]£3 employing it as a graduation house during the eight month3 as a graduation in which it is not used for crystallization. He has found, n0USP> that, all other circumstances being the same, the evapora- and is much lion eoes on nearly twice as fast in it as in the common gra- superior to the . " . . , r Ti . v Av . common one. duation house with faggots. It is necessary however, that the brine should be of the strength of 4° or 5° before it is brought thither, otherwise the ropes would speedily rot. This building with ropes, the only one in existence, is Dimensions of 90 met. [295 feet] long, 17 met. [55} feet] of which are the building. taken up by the pillars and the machine. It is divided into six arches, by party walls covered with boards ; and each arch contains 40 troughs, and consequently 2000 single ropes 8*3 met. [27*2 feet] long; so that there are in all 12000 ropes, making a total length of 99600 met. [326546 feet]. Little expense is required for repairs, as tjiree fourths «f the ropes last seventeen or eighteen years from the time they are put up. XII. Eclipses of the Satellites of Jupiter, observed by Johw Goldingham, Esq. F. R.S., and under his Superintend- ence, at Madras, in the East Indies*. ETWEEN the beginning of the year 1794 and the end Eclipses of Ju- of the year 1802 Mr. Goldingham had 151 observations of Piter's satel" eclipses of the first satellite of Jupiter, and 105 of the se- cond satellite, either at their immersion, emersion, or both. Of these he has given tables, noting the day, whether im- jnersion or emersion, apparent and mean time of observa- tion, time by the Ephemeris, longitude of Madras by the tables, and circumstances of weather, &c. As the judicious remarks prefixed to these tables may be of use to future ob- servers, it will not be unacceptable to several of our readers to find them here. They are as follows. The eclipses of the satellites of Jupiter were observed Telescopes, with achromatic telescopes, by Dollond, of three feet and half focal length, and magnifying power between 70 and * Phil. Trans, for 1808, p. 322s SO; 15* EJLIPSES OF THE SATELLITES OF JUPITER. Clock. Circumstances noted. Longitude of Madras. 80 ; having been constructed more immediately for this pur- pose, for which they were exceedingly well calculated in all respects. An astronomical clock, with gridiron pendulum, and dead beat, regulated by transits of the sun and stars, was used for the time; which was deduced from the transit of the sun nearest the eclipse, and verified by the one immediately pre- ceding or following. The circumstances under which the eclipses were ob- served are noted; from these may be inferred, how far the results are to be depended upon : those observed with th« " air clear and the planet high1' are the most satisfactory and valuable, nothing to the contrary being afterward ex- pressed. The longitude of the place, by numerous observations of various descriptions, is oh :21 : 14", or 80°: 18': 30' enst of Greenwich: by comparing this with the numbers in the la^t column, the difference of the tables will be obtained. The greater number of these eclipses were not visible at Greenwich, but have been found very useful, when corres- pondent observations have been taken in India. Persons not much in the habit of observing these eclipses, but desirous of obtaining as much correct information from their observations as possible, may find the following gene- ral remarks of use. Correspondent A correct difference of longitude, it would appear, is not observations to be expected, by comparing the time of observation with that in the tables ; it therefore becomes necessary to have a correspondent observation to compare with, or some satis- factory observations taken under a known meridian, about the time; from which the crrours of the tables may be found. Correspondent observations should, however, be obtained if possible : but it must not be supposed, that even these will give a correct difference of longitude, unless ob- served at both places, under the like favourable circumstan- ces, and with telescopes of the same powers. The air being clear ; the planet so high as to be out of the thick atmosphere, and to make the position easy; the telescope sheltered from the wind, and steady; neither moon- light nor twilightj and the satellite not near the body of the planet ; General re marks. necessary. Most favour- able circum- stances. ECLIPSES ©F THE SATELLITES OF JUPITER. 15£ planet: An eclipse observed under such circumstances will, 1 apprehend, be as perfect as it well can be; and a corre- spondent observation, taken under the like circumstances, will give a correct difference of longitude of the two places, provided the eclipse be observed' with telescopes of the same powers. Taking- the eclipses in the following tables observed un- Much affected der these favourable circumstances as the standard, and j^ unfavoura« comparing their results, as given in the last column, with stances, those of the others, it will be found, how much the latter are affected, by the eclipses having been observed when the atmosphere was hazy, or the planet very low, during twi- light, or when the moon was near the planet, or the satellite not far from the body of Jupiter; and that even if correspon- dent observations had been taken, under favourable circum- stances, at a known meridian, the difference of longitude given by the comparison would have been far from correct: the same eclipse observed at two places, under similar un- favourable circumstances, would possibly give a result near the truth ; as the observations at both places would be af- fected in the same way, but probably not in an equal de- gree, as it is not likely there would be exactly the same de- gree of haze, the same strength of twilight, &c. at both places ; and therefore those observations taken under the same favourable circumstances can only be relied upon with certainty. It may not be an easy matter to have telescopes at both ^-ffi» Itt places of precisely the same powers for these observations: telescopes at Madras we had two telescopes in use, constructed at the alike- tame time, in appearance precisely alike, and intended by Dollond to have been so in all respects; yet on repeated trials, one was found to have a decided advantage of several seconds over the other, showing the emersions sooner, and the immersions later by that quantity. In order to do away %0^ ln • the errour arising from a difference in the powers of tele- mersion and scones, immersions and emersions should be observed at both emerSI°n . ,.„, ,. , • i -ii i , should be ob* places ; the diiierence ot longitude will be as much greater served. than it ought to be by one series as less by the other, but the medium will be the correct difference of longitude of the places: it is possible also there may be some difference in Difference in the eyes, 156 SCIENTIFIC NEWS. the eyes of observers, any errour which may arise from this source will also be done away by this method. General re- Hence it would appear, that, in order to obtain a correct quisites. difference of longitude of two places from correspondent eclipses of the satellites of Jupiter, the circumstances at both places should be similar and favourable; and that the telescopes should have equal powers, or that both im- mersions and emersions should be observed, which indeed ought always to be done, where time will admit : also, that, the circumstances being favourable atone place and not so at the other, a result very different from the truth will be obtained. • : "~- ' SCIENTIFIC NEWS. Faikinson'sOr- J[ jt£ first volume of Mr. Parkinson's Organic Remains janic cmain . ^ & former World, which I have noticed in Vol. IX, p. 143, has been some time before the public; and I have now the satisfaction of announcing the second, which is no way in- ferior to its predecessor. I trust it will be a subject of gra-» tification rather than disappointment to my readers to find, that its indefatigable author has not been able to close hi$ labours on the fossil remains of the animal world with the present volume, and that he cannot even pledge himself to limit them to a third ; as he very judiciously means to ren- der it as complete as possible, without admitting any super- fluous matter. In his arrangement he nearly follows Wal- lerius, who, after treating of vegetables, proceeds through corals, worms, shells, insects, amphibia, fishes, birds, and quadrupeds up to man. The present volume is confined to zoophytes, many figures of which are given in twenty plates, executed with much elegance, and the greater part of them coloured after nature. To enter into any adequate detail of the whole, or notice all the most striking parts, would much exceed my limits; I shall at present confine myself therefore to the following observations on madrepores. Madrepores, Under the genus madrepore are placed all those corals, the SCIENTIFIC NEWS. 15^ the cavities of which are divided by lamelloe disposed in a stellular form. The animal, which in the recent coral fills these cavities, was first depicted by Donati in the 47th vo- lume of the Philosophical Transactions, p. 105, PI. IV, and in the Natural History of the Adriatic Sea by the same author. Its feet are in considerable number, and terminate externally in two conical prod actions, which, being placed on each side of every one of the lamellae that give the stel- lular form to the cavity of the coral, serve to affix the ani- mal to the circumference of its cell, and may with propriety be considered as the instruments, by which the little animal forms the lamellae themselves. The bases of these conical productions unite and form round bodies, which possess somewhat of the figure and of the properties of a muscle : they undoubtedly serving to lengthen or shorten the feet, and also most probably to regulate the force, with which they clasp the lamellae, on which they exert their plastic powers. The other ends of these round bodies terminate in small cylindrie tubes, which are attached to the shell of the animal, in the centre of which is seen its head, capable of moving with great quickness, and ornamented with several rays, which are most probably the arms or claws with which it seizes and secures the animalculae on which it feeds. Attributing the formation of these corals to the operations Manner in of the madreporean or medusean polype, let us endeavour to which the co- trace the little architect through its wonderful labours. ral is formed* Agreeable to the observations of Donati, each of the legs, as he terms them, of the polype are provided with two pro- cesses, which are applied to each side of one of the perpen- dicular laminae, whilst a muscular pyriform body, attached to the other end of the leg, gives to it the power of employ- ing that motion which is necessary for the accomplishment of its task. The young polype, disposed on an appropriate spot, may be considered as completing its operations by two distinct processes: the secretion and separation of carbonate of lime from the sea water, conveyed through the pyriform body ; and its deposition, at its moment of secretion, by the two small processes, where the economy of the animal directs. Proportioned to the number of legs possessed by the infant animal was probably the number of perpendicu- lar 158 SCIENTIFIC NEWS. !ur laminrt?, or pillars converging to the centre, which it be* gan to erect; these when raised to a certain height, appear- ing to have been connected together by a horizontal plate of the same substance. On these the animal erected simi- lar pillars, and placed on these a covering similar to that v-ith which he had completed the first compartment. Thus seems to have proceeded the incessant labours of the minute artist : and as the number of its legs, or instruments, in- creased, and as they extended in length, so must the num- ber of the perpendicular laminse, and the circumference of the horizontal plates have also augmented. Thus must this curious fabric have derived its fashion from the growth and form of this minute and wonderful animal. That the formation of these turbinated madrepores may have been thus effected does not appear difficult to conceive. Neither is it difficult to understand, that when the animal had attained its full extent of growth, the continuance of its labours would produce, not a body of a conical, but of a cylindrical form. Nor does it appear unlikely, that should any accidental circumstance change its horizontal position, a proportional deflection from 1he straight line would be occasioned ; and a coralline body of a curved form be pro- duced. Specimens of both these forms, it has been just remarked, are frequently found. Reports of the THE long expected Reports of the Preventive Medical MeJ]icalTn- Institution at Bristol, have been left by the late Dr. Bed- »tituation. does in some degree of forwardness. They will be com- pleted and published as soon as possible, by Mr. King and Dr. Hook. The former of these gentlemen has been Sur- geon to the Institution from its first commencement, and the latter has been connected with it since the month of March, 1804. Life of Dr. Dr. Hook is likewise about to publish a Life, &c. of Dr. Beddoes, with the approbation of his family and friends. Beddoes. Commercial Mr. JOHN CLENNELL, late of Newcastle, has un- Magazine. dertaken the editorship of the Tradesman, or Commercial Magazine. SCIENTIFIC HEWS. 159 Magazine. As this monthly publication, being of recent date, may be unknown to many of my readers, I shall just inform them, that its object is, to communicate general and useful information on the different subjects connected with trade, commerce, and manufactures. St. Thomas's and Guy's Hospitals. The spring courses of Lectures at these adjoining Hospi- Medical an* tals will commence as usual the 1st of February, viz. At St. Thomas's. Anatomy and Operations of Surgery, by Mr. Cline and Mr. Cooper. Principles and Practice of Surgery, by Mr. Cooper. At Guy's. Practice of Medicine, by Dr. Babington and Dr. Currt. Chemistry, by Dr. Babington, Dr. Marcet, and Mr. Allen. Experimental Philosophy, by Mr. Allen. Theory of Medicine and Materia Medica, by Dr. Curry and Dr. Cholmeley. Midwifery , and Diseases of Women and Children, by Dr. Haighton. Physiology, or Laws of the Animal Economy, by Dr. Haighton. Occasional Clinical Lectures on Select Medical Cases, by Dr. Babington, Dr. Curry, and Dr. Marcet. Structure and Diseases of the Teeth, by Mr. Fox. N. B. These several Lectures are so arranged, that no two of them interfere in the hours of attendance; and the whole is calculated to form a Complete Course of Medical and Chirurgical Instructions. Errata in our last Number. Page line 2 13 For E and B, read E A B. 12 from bot. For and — ~, read varies inversely a* rad' radius. * METEOROLOGICAL JOURNAL For JANUARY, 1809, Keptby ROBERT BANCKS,Mathematical Instrument Maker, in the Strand, London. THERMOMETER. BAROME- TER, WEA THER. DEC. •— i • a .'flJ >- - J= Day of < In tc V 9 A. M. Night. Day. o> o> x~ j5 27 32 33 34 30 2944 Cloudy Rain 28 34 37 39 35 29'58 Rain Ditto 29 36 39 40 37 29'50 Ditto Ditto 30 38 39 43 33 29*49 Ditto Cloudy 31 34 38 40 35 2959 Ditto Rain JAN. 1 36 37 40 35 29-60 Ditto Ditto ' 2 37 36 39 30 29*47 Ditto* Ditto 3 31 30 32 28 29'33 Ditto Snow 4 30 32 33 32 29*63 Ditto Rain 5 37 43 44 42 29 67 Fairf Ditto 6 42 42 44 38 29*50 Ditto Cloudy 7 40 39 44 36 29*32 Ditto Rain 8 40 40 42 36 28-82 Rain Ditto 9 40 40 44 34 29-37 Fair Ditto 10 38 39 43 36 29'20 Cloudy Ditto 11 38 33 40 33 29'38 Ditto Fair 12 35 32 36 31 29-49 Ditto Ditto 13 33 34 38 28 29'69 Ditto Rain 14 30 32 36 28 29*78 Ditto Cloudy- 15 30 28 30 26 2975 Ditto Snow 16 28 27 30 27 30-03 Ditto Cloudy 17 28 27 28 21 30*06 Fair Ditto 18 23 23 27 20 29-88 Ditto Fair 19 24 29 30 29 29*72 Snow Snow J 20 28 30 32 25 29*48 Ditto F°ggy 21 32 32 33 29 29*46 Ditto Cloudy 22 32 32 33 21 29* J 2 Ditto Snow 23 22 31 33 30 29*67 Sleet § Fair 24 32 33 40 33 29'40 Rain Rain 25 36 33 39 32 29-43 Ditto Cloudy 26 44 43 46 ( 40 29*22 Cloudy Fair * Snow at 10 P. M. heavy snow all night. t The constellation Orion brilliant. Very black in the north. t At 1 P. M. appearance of change, rain freezing as it fell. The thermome- ters in a few minutes covered with ice, succeeded by rain and snow all the night. § At 11 heavy snow. i A JOURNAL OF NATURAL PHILOSOPHY, CHEMISTRY, AND THE ARTS. MARCH, 1809, ARTICLE I, A Letter on the Alterations, that have taken place in the Structure of Rocks, on the Surface of the basaltic Coun- try in the Counties of Derry and Antrim. Addressed to Humphry Davy, Esq. Sec. R.S, By William Ri- chardson, D.D.* SIR, JL Request you will be so good as to lay before the Roj^al The basaltic Society the following observations on the Natural History of c°unJ*y near J *-*■'-. i -n- , r^ J the Giant's that part of Antrim, (contiguous to the Giant s Causeway,) Causeway ira which you and I examined so carefully together. I know port*nt to geo- not any country, that deserves so well to have its facts faith- fully recorded; from the important conclusions to which they lead. The basaltic area (taken in its whole extent) comprehends the greater part of Antrim, and the east side of Derry to a considerable depth. * Philos. Trans, for 1808, p. 187. Vol. XXII. No. 98— -March, 1809. M In 162 «N THE BASALTIC COUNTRY IN IRELAND. and affords In a geological point of* view, Nature * has been very kind to Us jwnW. to tms district, for not content with assembling together in a small space so many of her curious productions, and ar- ranging them with more regularity and steadiness than in any other country described, she has condescended occa- sionally to withdraw the veil, and lay herself open to view, often exhibiting a spectacle equally gratifying to the admirer of magnificence, and to the curious naturalist, who can here, by simple inspection, trace the arrangements, which are to be discovered elsewhere only by penetrating beneath the surface of the earth* Particularly As soon as we enter the basaltic area, we begin to perceive th oast traces of these arrangements; as we advance farther north, they increase; and in the tract near the shore, and espe<* cially at the island of Rathlih, which seems to have come fresher from the hand of nature than the rest of our area, the stratification of the whole is perfectly visible, and the nature of the several strata laid open to us at their abrupt and pre- cipitous terminations. To the south- To the southward we perceive the distinctive features tinct. abate, and wear away; the basaltic stratification indeed re- mains, but is n6 longer displayed to us in the same manner; the neat, prismatic, internal construction of the strata, which occdrs so frequently on and near the coast, is scarcely to be met with at a distance from it; a rude columnar appearance is all we find, and that but rarely. O the north It is at the periphery of our area, and especially at its pTeteiv open nortnern side, that every thing is displayed to the greatest advantage; here we have perpendicular facades often con- tinuous for miles, and every separate stratum completely open to examination. Four most Of these facades, four are more distinguished by their s l * grandeur and beauty than the rest, Magilligan Rock, Cave Hill, Bengore, and Fairhead. The two former are at the extreme points of the north- west diagonal of our area, and nearly forty miles asunder ; * By the word Nature, which frequently occurs in the course of this Memoir, 1 always mean, according to Ray's definition, the wisdom of God in the creation of the world. they DN THE BASALTIC COUNTRY IN IRELAND* \(y$ they are at the summits of mountains, and accessible by . land. The precipitous faces of Fairhead and Bengorei to which I had the pleasure of attending you, and which are visible Only from the sea» are the most beautiful, and the most curious ; for the strata, which at Magilligan and Cave Hill are all nearly similar, at Fairhead and Bengore are much diversified. Of Fairhead I have already published an ac- Fairhead. count in Nicholson's Journal, for December, 1801, quarto series, and I now propose to execute an intention, which I have had for some years* of giving a minute account of B we tnow not well how. Eighth Stratum, (e). 0th stratum. The next stratum is of the same variety of basalt with the third, tjiat is, irregular prismatic ; it is fifty-four feet thick, and in the views distinguished by the letter (c) : where it emerges at the south-east corner of Portmoon, it is quite accessible by land, and affqrds the best opportunity I know for examining this* species of basalt, as it is there very neat* There is little more of this stratum seen in the facade of Portmoon for want of perpendicularity, but it forms the lower ON THE BASALTIC COUNTRY IN IRELAND. 171 lower frustum of the great conical island Beanyn Daana, EeanynDaan** and the whole of the smaller, except the base ; it is well displayed over the remainder of the precipice, it forms the intermediate stratum between the magnificent colonnades at both Bengore and Pleskin, and finally is lost just over the Giant's Causeway. Large globular fragments have fallen from it, aud are scattered about the causeway. Ninth Stratum, [I). This stratum is forty-four feet thick, that being the exact 9th stratum* length of the neat pillars composing it; at its emersion it forms the bases of the two conical islands in Portmoon, and is no more seen in that bay, but immediately to the north- ward it begins to show itself in colonnades and groups, some of them resembling castles and towers. It ascends along the precipice obliquely, like those above it, forms the lower range at Bengore and Pleskin, from which last it dips to the westward regularly, composes the group at Port Noffer, called the Organs, seen from the The Organs* causeway, and finally at itsUmmersion, or intersection with the plane of the sea, it forms the beautiful assemblage of neat pillars., so long distinguished by the name of the Giant's Causeway. At these two intersections, each of them accessible by land and water, the prisms exactly resemble each other in grain, size, and neatness ; the interval between them is full two miles, through great part of which this stratum is dis- played at different heights; it culminates between Pleshhi and Bengore, with its lower edge more than two hundred feet above the water. We see now what a diminutive portion of our vast ba- saltic mass has, until lately, monopolized the attention of the curious; and even after it was discovered, that we had many other, and much finer collections of pillars on the same promontory, it never occurred to those who were pre- paring to give accounts of them to the public, to examine whether these were mere desultory groups, or detached parts of a grand and regular whole, which a more compre- hensive view of the subject would soon have laid open to them. * Tenth )7£ 0N T1IE BASALTIC COUNTRY I-V IRELAND. Tenth Stratum, (a). 10th stratum. The stratum upon which the pillars of the preceding rest is ochreous, red as minium, and about twenty feet thick ; it is scarcely seen at Portmoon, a patch alone of its surface being distinguishable under water at low tide; but imme- diately to the northward it shows itself, and from its bright colour makes a conspicuous figure across the face of the pre- cipice in a course of more than a mile and a half; its last KavinTalley. appearance to the westward is at Rovinvalley, the opposite point of the bay from the Gianfs Causeway, from which we have a good view of it. The final dip and immersion of this tenth stratum, as well as its emersion, are lost for want of perpendicularity. ITth to lGth The six remaining strata are all similar in material, but strata. differing much from each other in thickness ; they are all of that description called tabular basalt, sometimes show-, ing a faint disposition to assume a columnar form at their edges, and always separated from each other by ochreous layers. Not so distinct These six strata are not so perfectly distinct as those above as the others. them, for sometimes we think we can count seven, and again not more than five; nor does each of these preserve the same thickness through their whole extent, for they are deeper towards the northern point, where they culminate, forming by themselves a perpendicular facade near two hun* dred feet high, but they grow thinner as they recede from this centre. The jets of black rock in the view of Purtmoon aTe the emersions of these strata; their last appearance on the west *ide is ut Rov'mvalley, where they strongly display the incli- nation si iheir strata (the same with all the rest) to those approaching from the westward ; their final immersion is lost for want of perpendicularity. f shell now proceed to select from the great mas.;! of facts, that are exhibited on the face of Bcngore promontory, and eccur in the contiguous basaltic country, such ag seem ap- plicable to geological questions, and likely to throw light on ftucb sub';- Facts ON THE BASALTIC COUNTRY IN IRELAND. 173 Facts applicable to geological Questions. Geological 1. Every stratum preserves accurately, or very nearly, the The strata uni- same thickness through its whole extent, with very few ex- ^™ m l lc ceptions. 2. The upper and lower surface of each stratum preserve Both surface* ii •• i .i ii ,i parallel, unless an exact parallelism, so long as they are covered by another one has been stratum ; but when any stratum becomes the superficial one, exposed to the its upper surface is scolloped, or sloped away irregularly, while the plane forming its bage continues steady, and recti- lineal; but the parallelism of its planes is resumed as soon 4s another stratum is placed over it. 3. The superficial lines bounding the summit of our fa- The line of the cades, and our surface itself, are unconnected with, and un- verned by the affected by, the arrangement of the strata below them. strata below. 4. Nature, in the formation of her arrangements, has ne- ver acted upon an extensive scale in our basaltic area, (at least on its northern side, where our continuous precipices enable us to determine the point with precision,) but changes Materials and her materials, or her arrangement, or both, every two or *rrangenJent , . , . J frequently three miles, and otten at much smaller intervals. changed. 5. AVherever there is a change of material, as from one The changes stratum to another in a vertical line; or where the change is alwayssudden, in a horizontal direction by the introduction of a new system ; or where a whyn dike cuts through an accumulation of strata; in all these cases the change is always per saltum and never per gradus, the lines of demarcation always distinct, and well defined; yet the different materials pass into each -without inter- other without interrupting the solidity and continuity of the [jJJulty! C°** whole mass. 6. The facades on our coast are formed as it were by ver- Precipices. tical planes, cutting down, occasionally, the accumulations of our strata; the upper part of these facades is generally perpendicular, the lower steep and precipitous. 7. The bases of our precipices commonly extend a con- Their base* ex- siderable way into the sea; between the water and the foot tend int0 A* of the precipice, (and especially near the latter) there is frequently exhibited the wildest and most irregular scene of confusion, by caTeless observers supposed to be formed by Apparent fra^ the ruins of the precipice above, which have fallen down; mefttso° tl,e* such. 174 ON THE BASALTIC COUNTRY IN IRELAND notfallen down such, no doubt, was "Mr. Whitehurst's idea, when he de* scribes one of these scenes its " an awful wreck of the ter- *' raqueous globe." But a more attentive observer will soon discover, that these capricious irregularities, whether in the form of rude cones, as at Bcanyn Daana, and the west side of Pleskin; or towers, as at the dike of Port Cooan, and Castro Levit, at the foot of Magilligan facade; or even spires and obelisks, as to the westward of Kenbaan, and at the Bull of Rath* lin; yet all of these once formed part of the original mass of coast, stratified like it, and their strata still correspond in material and inclination with those in the contiguous pre- cipice". Perpendicular g. These vertical sections or abruptions of our strata are Mdufthft1* ky no means confined to the steeps that line our coast; the cw&t. remaining boundary of our basaltic area has several of them equally grand ; and similar abruptions, or sections (though not so deep) are scattered over a great part of our area, and especially on the ridges of our hills and mountains, which are cut down in many places like a stair by the sudden ab- ruption of the basaltic stratum. The materials 9. Wherever the strata are thus suddenly cut off, whe- OQoue sldeofther it be a mass of accumulated strata, as in the facades these carried . .... v •tray. on our coast, or solitary strata, as in the interior; the ma- terials on one side of the abruption are completely carried away, without a fragment being left behind, while on its other side the untouched stratum remains intire and undis- turbed. I shall not proceed to apply these facts to support, or in- validate, any of the numerous theories, which have given rise to so much controversy, in which I myself (as you know) have borne some part; I shall look to nature alone, without much reference to opinious, and shall endeavour to trace, by the marks she has left behind her, some of the grand operations she once executed on the surface of our globe. TheSdivisions Varro divided the time elapsed since the beginning of the •f history ap- world xinto three portions, which he distinguished by the turaA JbtoryT" names, prolepticum, fabulosum, and historicum. The first comprehended the period of abiolute darkness ; ON tllE BASALTIC COUNTRY IN IRELAND. 1 7^ in the second some faint lights were thrown upon the history of its events by fable and tradition ; in the third, the histo- rian had the common aids, from which history is usually compiled. The natural history of the world seems to admit of a cor- feriof °f abs«- responding division. In the first I include the formation of our strata, their induration, their derangement from the horizontal position in which they seem originally to have been placed, and the operation of cutting them down by so many whyn dikes. In the second division, corresponding to Varro's fabulo- Fabulous pt» sum, I comprehend the operations performed upon our globe posterior to its final consolidation, and antecedent to all history or tradition ; operations therefore that can be esta- blished by the visible effects alone which still exist, written in strong characters. The third division contains the period since we acquired Historical p& eome knowledge of natural history, became acquainted with n * causes and effects, and able to trace the connection between them. With the operations performed in the first division (cor- responding with Varro's prolepiicumj modern theorists as* Modern thet* sume that they are well acquainted, able to account for every nsls* appearance, and to detail the whole process of original formation. I however shall decline noticing these early pro- cesses of nature, and limit myself to the second division of natural history, hoping from the prominent features of my country that remain still undefaced, and from its curious facts, to trace and demonstrate the great effects, that have been produced upon our surface ; and though I do not pre- sume to advance farther, I perhaps may assist in clearing the way for future naturalists, and by establishing effects, encourage them to proceed to causes, and help them to dis- cover the powers and agents, by which these grand opera- tions have been executed, (To be concluded in our next.) n> }~g PURIFICATION OF CAMPHOR. II. On the Purification of Camphor by Means of Potash. In a Letter from a Correspondent. To Mr. NICHOLSON. SIR, Camphor pu- Jjj ROM an idea of pure pojash having a greater affinity potash- *°r nxed °ils> tnan tne essential ones, and considering cam- phor as one of the latter in a concrete state, I was induced to try its effects on some, which, though not the unrefined camphor of commerce, was very impure, and possessed con- siderable empyreumatic smell. After several experiments with mixtures of it, different fixed oils, and sand (in order to divide the particles), I found, that, when sublimed with a small admixture of pure potash, the oily particles and em- Subcarbonate pyreumatic smell were detained by the alkali. The subcar- nie ectua . donate does not answer the purpose, because in that state the affinity of potash for oils is less than when entirely deprived of carbonic acid. 6 p. camphor, Two drachms of camphor with considerable empyreuma- S olive oil, 24 tic smell, and dirty, w^re mixed with one of olive oil, and ^"astTmixed eignt °f sand; after which twenty grains of pure potash and the cam- were added, and heat applied ; but though it was greater phor subli- t|jan Js necessary for its sublimation, the product was per- fectly free from empyreumatic smell, and a little whiter than it generally is. Substituting linseed oil produced no alteration in the pro- duct ; and supposing, that the fixed oily panicles of cam- phor are not more liable to render it empyreumatic than those employed, which did without the addition of the al- kali, I take the iiberty of submitting this to your perusal, and am, Sir, yours, &c. PHILOCHEMICUS. Jan. 4, 1809. iNATOMlCAfc STRUCTURE Of THE WOMBAT. \jf III. An Account of same Peculiarities in the anatomical Structure of the Wombat. By Evarard Home, Esq. F. R. S*. Male wombat was brought from the islands of Basse's Straits, by Mr. Brown, the naturalist attaehed to Cap- Ej^ftfij* tain Flinders's voyage of discovery. It was entrusted to my care, and lived in a domesticated state for two years, which gave me opportunities of attending to its habits. It burrowed in the ground whenever it had an opportu- nity, and covered itself in the earth with surprising- quick- ts ha°lts> ness. It was quiet during the day, but constantly in mo- tion in the night: was very sensible to cold; ate all kinds of vegetables; but was particularly fond of new hay, which it ate stalk by stalk, taking it into its mouth like a beaver, by small bits at a time. It was not wanting in intelligence, and appeared attached to those to whom it was accustomed, and who were kind to it. When it saw them, it would put up its fore paws on the knee, and when taken up would sleep in the lap. It allowed children to pull and carry it about, and when it bit them did not appear to do it in anger or with violence. It appeared to have arrived at its full growth, weighed about twenty pounds, and was about two feet two inches long. The koala is another species of the wombat, which par- takes of its peculiarities. The following account of it was The koala an* sent to me some years ago by Lieut. Colonel Paterson, 0t " *pecies* Lieutenant-Governor of New South Wales. The natives call it the koala wombat; it inhabits the forests of New- Holland, about fifty or sixty miles to the south-west of Port Jackson, and was first brought to Port Jackson in August, " 1803. It is commonly about two feet long and one high, in the girth about one foot and a half; it is covered with fine soft fur, lead coloured on the back, and white on the belly. The ears are short, erect, and pointed; the eyes generally • Abridged from the Philos. Tram, for 1808, p. 304. Vol; XXII.— March, 1809. N ruminating, 178 fruntedby the New-Hol- landers. It* habits. 'The wombat ha^ been in part described. Peculiarities of its hind legs. ANATOMICAL STRUCTURE OF THE WOMBAT; ruminating, sometimes fiery and menacing; it bears no smart resemblance to the bear in the tore port of its body ; it had no tail; its posture for the most part is sitting. The New Hollanders eat the flesh of this animal, and therefore readily join in the pursuit of it; they examine frith wonderful rapidity and minuteness the branches of the loftiest gum trees; upon discovering the koala, they climb the tree in which it i» seen with as much ease and expedition as a European would mount a tolerably high ladder. Hav- ing reached the branches, which are sometimes forty orlifty feet from the ground, they follow the animal to the extre- mity of a bough, and either kill it with the tomahawk, or take it alive. The koala feeds upon the tender shoots of the blue gum tree, being more particularly fond of this than of any other food; it rests during the day on the tops of these trees, feeding at its ease, or sleeping. In the night it descends and prowls about, scratching up the ground in search of some particular roots; it seems to creep rather than walk: when incensed or hungry, it utters a long shrill yell, and assumes a fierce and menacing look. They are found in pairs, and the young is carried by the mother on its shoulders* This animal appears soon to form an attach- ment to the person who feeds it. A specimen of this animal has since been sent to me in spirits; the viscera had been removed, but the male organs of generation, and the structure of the limbs, were the same as in the wombat. There was no subdivision of vessels in the groin as in the tardigrade animals. The external form of the wombat has been described by Mr. Geoffroy in the second volume of the Annales du Mu- seum National de France ; and several parts of its internal sti ucture have been taken notice of by Mr. Cuvier in his Lemons d'Anatomie comparee. It only remains to mention such peculiarities as have either been slightly touched upon, or entirely passed over in the different accounts. Among these is the mechanism of the bones and muscles of the hind legs, which differs in many respects from that of all other animals, except the koala. The following account of it is drawn up at my desire by Mr. Brodie, from an accu- rate examination of the parts. « Ther* ANATOMICAL STRUCTURE OF THE WOMBAT. 179 " There is no patella; but the tendon of the extensor muscles of the leg, where that bone is usually situate, is much thickened. " The fibula is proportionably larger than in most ani- mals. At the upper extremity it is broad, and has two dis- tinct articulating surfaces: the anterior of which is articu- lated to the tibia, and the posterior to a small borie of a py- ramidal shape, which is connected to the tendon of the ex- ternal head of the gastrocnemius muscle like a sesamoid bone. The lower extremity of the fibula is large, and forms about half of the articulating surface for receiving the tar- sus at the ankle. An interarticular cartilage is here inter- posed between the tibia and the fibula, and another between the fibula and the tarsus. " The fibula has a slight degree of motion on the tibia at its upper end, and a half rotatory motion on it at its lower end. Between the two bones is a strong muscle, which passes from one to the other throughout their whole length. The fibres have their origin from the inner edge of the fibula, and pass obliquely inward and downward to be inserted into the opposite surface of the tibia. When this muscle con- tracts, it pulls the fibula forwards, and produces a degree of rotation on the tibia, which turns the toes inwards. The an- terior surface of the muscle is covered by a thin fascia or in- terosseous ligament, and there is another fascia less complete on its posterior surface. The muscle of the legs,correspofiding to the biceps flexor of the human subject, is inserted into the posterior part of the fibula, and is an antagonist to the muscle just described. Its action brings the toes back to d straight line, but does not turn them Outwards." This mechanism is met with in two animals, whose mode This structure of life is very different, the one living on trees, the other comm°n to - , i,i, • , , , • . . , two animals of not; but as they both burrow in the ground diinngthe night, different ha- lts use appears to be for throwing back the earth while the bits* animal is burrowing* There is nothing at all similar to it in the hind legs of the mole, or other burrowing animals. The internal structure of the stomach of the wombat re- Stomach,, srembles very closely that of the beaver. This is so differ- ent from that of the kangaroo, and all the other animals of the oposBum tribe, that it forms a very extraordinary peculiarity. N2 IVa 180 CHANGES PRODUCED IN AIR BY RESPIRATION. IV. On the Changes produced in Atmospheric Air, end Oxigcii Gas, by Respiration. By W. AlleN, Esq., F. R.S., and W. H. PepVs, Esqi, F. R. S*. Respiration J|_ HE process of respiration, Or breathing, is so intimately tinted " mVCI" connected wittl our existence in life, that from its first mo-» ments to the final close, sleeping and waking, this necessary action is constantly maintained: nor can it be suspended even for a few minutes without considerable pain and the utmost danger. This important process has of course ex- cited the curiosity both of ancient and modern philosophers ; among the latter we find the distinguished names of Ma vow, fcjmany, Priestley, Goodwin, Menzies, Spallanzani, Scheele, Lavoi- sier, and Davy, whose successive labours have thrown great light upon this difficult subject, and prepared the way for farther investigation ; but it is impossible to take a review of what has already been done, without perceiving, that somte but some im- *mPortant points were by no means satisfactorily settled ; an portant points accurate method of separating the different gasses, and as- still unsettled. certaining their exact proportion in any given mixture, was still a desideratum when many of the experiments were made; and it is only of late years that eudiometry has at- Residual pas in *ame(l its present perfection. The quantity of residual gas the lungs often in the lungs after a forced expiration was a matter in dis- a lfncu ty. ^^e among former experimenters, come making it one hun- dred and nine cubic inches, and others only forty ; and yet it is of the utmost importance in all calculations upon the effects produced, especially upon small portions of gas, that the state of the lungs should be accurately determined ; this constitutes the great difficulty in the investigations. We this obviated, therefore commenced our labours by constructing an appa- tus, in which we are able to respire from three to four thou- sand cubic inches of gas, conceiving, that in this quantity, the errour arising from the residul gas in the lungs must be so much obviated as to permit the most satisfactory results. » Philos. Trans, for 1808, p. 249. The' TKdwlronr PJalar Journal VdLJZZK. Fl.6.h. 1%1 CHANGES PRODUCED IN AIR BY RESPIRATION. JgJ - The apparatus consists of three gasometers, two of which Apparatus for are filled with mercury, a»id one with distilled water. purport. The water gasometer which belongs to the Royal Institu- tion is capable of holding four thousand two hundred cubic inches of gas, and each of the mercurial ones three hundred cubic inches; the apparatus was so arranged, that the inspi- rations were all made from the water gasometer, and the ex- pirations into the mercurial gasometers alternately. Each of the gasometers is furnished with a graduated scale, and they aire all made to range with each other, so that the quantity of gas inspired and expired could be immediately and ex- actly ascertained: to each of tlua mercurial gasometers a glass tube is fixed, aud made to euter a mercurial bath, from which portions of the expired air could at any time be taken for examination. By the kindness of our friend Silvanus Bevan, we are enabled to give an accurate drawing of the apparatus. Description, PI. VI, fig. 1. The communication with the water gaso- Referenced meter. the plat*. 2. A cock so constructed that it might be made to com- municate with either of the mercurial gasometers, while at the same time all connexion with the other was cutoff. A. The mouth piece. 3 to 10. Brass cocks. G. I, and G. 2. Mercurial gasometers. S. S. Scales graduated to cubic inches. M, Mercurial bath. The large reservoir or water gasometer is not shown in this drawing, it having been so frequently described in che- mical works. Manner of conducting the Experiment. Qur first care was, to be certain that all the parts of our Mannerof con- apparatus were perfectly air-tight, and this, from the nature experin/nts of it, was very easily ascertained ; we agreed, that the breath- ing should always be performed by one of us, and the regis- tering &c. by the other, as each would by these means ac- quire 182 CHANGES PRODUCED IN AIR BY RESPIRATION, quire a greater degree of dexterity in performing his part, and the results would be more uniform. Experiment. The water gasometer being filled with common air to a certain mark upon the scale, and the mercurial ones com- pletely empty, the person to breathe, whom we shall uni- formly call the operator, was seated upon a stool, with his mouth e,ven with the tube A, his nose being secured with a steel clip. He made as complete an expiration as possible into the open air, then applying his lips to the tube, and keeping his left hand constantly on the cock 1, and his right hand on the cock 2, he opened the communication with the water gasometer, and made an inspiration; then immedi- ately closing it, he opened with his right hand the cock at 2; and that at 4 being also opened, he expired into the mer- curial gasometer G 1 ; then closing 2, which cut off all communication with the mercurial gasometer, he opened 1, in order to make a fresh inspiration ; then closing it, he again opened 2, and expired into the mercurial gasometer; and proceeding in this way, always taking care to shut one cock before the other was opened, the air was made to pass from the water gasometer, through the lungs of the operator into the mercurial gasometer, and this with great ease, as the diameters of the tubes were purposely made large. The scale of the mercurial gasometer was carefully noticed, and when nearly full, the cock 4 underneath was shut off: then, by a signal from the operator, his colleague opened 3, and the expirations were received in G 2. While this was filling, the number of cubic inches in G 1 was registered, a portion saved in the mercurial bath, and the rest quickly expelled. This operation was repeated, until the contents of about twelve or thirteen mercurial gasometers were taken off: the operator always concluding with a strong effort to empty his lungs as completely as possible. The quantity inspired from tha water gasometer was then compared with the quantities expired into the mercurial gasometers, and the difference noted. The following are the results of the first ten experi- ments. No. CHANGES PRODUCED IN AIR BY RESPIRATION. }^J Cubic inches Cubic inches Results of the $o. Time. of common air of gas Deficiency. 1st ten experi- inspired. expired. ments. 1. time not noted 3760 3741 19 2. 11 minutes 390Q 3869 31 3. lOf % 3624 3620 4, 4. YOi 3570 3550 20 5. 11 • 3685 3653 &2 6. 11 * 3380 3355 2$ 7. 10f 3180 3141 39 8. 10* 336'0 3298 §2 9- 10| 3290 3267 23 10. 11 3580, 3543 37 In this last experiment we ascertained, that the expired 08 of carbo- gas contained 8 per cent of carbonic acid. n»c acid in the The breathing in these cases was as nearly natural as we The breaking conceive it possible to. be in any apparatus: the operator was nearly natural scarcely fatigued, and his pulse not raised more than about ^^het one beat in a minute; the respirations however were deeper and fewer than natural, amounting only to about 58 in ele- ♦ ven minutes, whereas from repeated observations at different and distant times he makes 19 in a minute. The smallness A greatcr de-" of the deficiency surprised us very much, as, from the re- rkiency ex- ports of other experimenters, we had been prepared to expect ' a much greater loss. It might be objected, that the air was rarefied by passing through the lungs; but this was almost immediately counteracted by the mass of quicksilver in the gasometers, which amounted at least to one hundred and fifty pounds; and we have repeatedly noticed, that air un- der these circumstances has suffered no perceptible diminu- tion by standing for a considerable time; in one case, in which air from the lungs was driven into the mercurial gas- ometers for twenty-seven minutes, the temperature of the quicksilver at the end of the experiment was not raised half a degree of Farenheit's thermometer. The deficiency, in but eren this our opinion, principally arises from the difficulty in bring- arises print- ing the lungs precisely to the same state after, as before the feft ^i^the** experiment; and it must be recollected, that the operator lungs. commenced by a forcible expiration into the open air, but fi- nished by a forcible expiration into the mercurial gasometer. Now, 1S4 11th experi- ment. CHANGES ?RODUCED IN AIR BY RESPIRATION. Now, although this gasometer was counterpoised by weights in the scale attached to it, yet we can easily conceive, that more resistance might be afforded to thecomplete evaluation in the latter case than in the for mer,and consequently the lungs might contain a few inches more after the experiment than before it, which might in some measure account for the de- ficiency. In the eleventh experiment, portions of gas were taken off from each of the mercurial gasometers as they were fil- led, and these portions being afterward mixed were care- fully examined. Eleventh Experiment. Thermom. Bstroin. Faht. 304 50* Cubic inches of common air Cub. in. Time, inspired. expired. 11 rain. 3460 3437 Defici- ency. 23 All the expe- riments made with great care. Component parts of the expired gas, To prevent repetition, we shall here state, that all the trials were made in the same manner, and with the same appara- tus, namely, the eudiometer, described in the Society's Transactions for 1807, in which one cubic inch is divided into one hundred parls*; and that in almost every instance we made two, and sometimes three experiments on the same gas, and derived fresh confidence from the remarkable co- incidence and uniformity of the results. No precaution was at any time omitted which appeared to us necessary to insure accuracy. One hundred parts of the expired gas being agitated with limewater in the eudiometer, the limewater became turbid, and 8*5 parts of the gas were absorbed, which were conse- quently carbonic acid ; the remaining 91*5 parts were treat- ed with the green sulphate of iron, saturated with nitrous gas, as recommended by professor Davy, and afterward with the simple solution of the green sulphate, when 12*5 parts were absorbed, which were consequently oxigen, and the remaining 79 azote. ♦ See our Journal, vol. XIX, p. 80. JO0 CHAXOft PRODUCED I* AIR BY RESPIRATION* 1 g5 iOO parts of the expired gas therefore consisted of 8' 5 carbonic acid. 12*5 oxigen 79* azote. 100. The air contained in the water gasometer, previous to the and of the air [periment, 100 parts of experiment, being examined by the same tests, consisted in j^l"^- t0 re" 21 oxigen 79 azote. 100. In trying common atmospheric air with Hmewater, we No carbons could never find any quantity of carbonic acid perceptible *c CHANGES PRODICED IS AIR BY RESPIRATION. Inordinary re- We are very much inclined to think, that in ordinary re* STteiurned0 sPu*a^on> a great part of the air is returned unaltered, viz. unahered. that contained in the fauces, in the trachea, and probably a portion of that in the larger branches of the bronchia. If this circumstance be not adverted to in experiments upon small quantities of air, the results can never be correct. There is even a considerable difference in the quality of the first and last portions of a single inspiration. In some ex- periments made with a view to this subject, a small quantity pf the first portions, given off in a common and natural ex- piration, was received in a vessel over mercury; on examina- tion, it contained only 3*5 per cent carbonic acid; in other experiments the first portions contain from three to five per cent; while the general average appears by the 11th, 12th, and 13th experiments, to be about eight. 204 cubic The operator, after rather more than a natural inspira- contained '095 ^on> expiree} £04 cubic inches into the mercurial gasome- of carbonic ter, making his utmost efforts to press as much as possible .»«*«• out of the lungs. These contained 9*5 per cent of carbo- nic acid, Here we are to recollect, that these 204 cubic inches contained the first, as well as the last portions; the t]rst portions have been proved to contain only from three to live per cent; consequently the last portions must contain more than appears by the average ; that is, more than 9*5 per cent. It now appeared to us of consequence to ascertain exactly what happened to a given volume of atmospheric air, when it was inspired and expired as often as possible. Fourteenth Experiment*, J4th cxperi- Three hundred cubic inches of atmospheric air were ad- ■ .ent* 4 .. mitted into the mercurial gasometer G 1 ; tjie other, G 2, Air repeatedly - °. j j xi ' respired. was empty. The nose being properly secured, and the mouth applied to the tube A, as usual, air was drawn from G 1, and by half turning the cock 2, was expired into, G 2, This was repeated until the contents of G 1 had been made to pass through the lungs, and transmitted to G 2. The * In this experiment there was obviously no occasion to make allow? wee for the air contained in the tubes and sockets. We find its volume to fce eighteen cubic inches, m CHANGES PRODUCED IS AIR BY RESPIRATION. |Q£ air was then inspired from G 2, and expired into G i, until G 2 was nearly empty. This was repeated about eight or ten times during three minutes, until respiration became ex- tremely laborious, and the operator desisted. The whole 300 cubic inches must have passed eight or ten times through the lungs; and we confidently expected, that on examining the air we should have found an unusual pro- portion of carbonic acid. But 100 parts gave onl? 9*5 carbonic acid, Compo-atttt " _ . parts of Oie n» 5*5 oxigen, 4j**«fc 85' azote, 100 Here was an increase of six parts in 100 of something which the tests for oxigen would not take up, and also a loss of six per cent oxigen. This seemed to convince us, that under certain circumstances, as during some peculiar alteration in the vital functions, gaseous oxide of carbon, carburetted hi- drogen, or some other gas not absorbable by lime water or the tests for oxigen, might be given off from the lungs, and we accordingly determined to repeat Cruikshank's experi- ments with hyperoxigenized muriatic acid gas. We procured the gas from hyperoxigenized muriate of Gaseous oxide potash by means of muriatic acid, and mixing it with a verted 'mS>w!r« known portion of gaseous oxide of carbon in a flint stopper bsnic add by bottle, the mouth of which was immersed in mercury for ^/muriatic1* twenty-four hours, the gaseous oxide of carbon was convert- acid $*►• ed into carbonic acid gas, as was proved by its effects upon iime water, which, when both the gasses are pure, absorbs them entirely after they have remained together for twenty- four hours; it was plain, therefore, that we had the means of detecting gaseous oxide of carbon, and doubtless carbu- retted hidrogen, if any should be contained in the expired gas. From a conviction of the importance ofthese experi- ments we were determined to take nothing upon trust. . Fifteenth Experiment, We repeated the 14th experiment with a little variation. 15tb expert In this case we employed only one of the mercurial gasome- ment- ters, 1Q0 CHANGES PRODUCED Itf AIR BT RESPIR-ATION. Air repeatedly ters, into which exactly 30O cubic inches of atmospheric respired. . » • 1 rru t t air were admitted. 1 he operator, having made an easy ex- piration, applied his mouth to the cock at the lop of the bell glass, and the time being noted, began to breathe; in less than a minute he found himself obliged to take deeper and deeper inspirations; and at last the efforts of the lungs to take in air became so strong and sudden, that the glass was in some danger of being broken against the side of the gaso- meter. A great sense of oppression and suffocation was now- felt in the chest, vision became indistinct, and after the second minute his whole attention seemed to be withdrawn from sur- rounding objects and fixed upon the experiment. He now experienced that buzzin the ears which is noticed in breath- ing nitrous oxide, and after the third minute had only suf- ficient recollection to close the cock af eran expiration. This secured the result of the experiment; but he became so per- fectly insensible, that, on recovering, he was much surprised at rinding his friend and the assistant on thetable in theactof supporting him. It was noticed that he made thirty-five in- spirations during the experiment. We now examined the air which had been so treated. theaircxa- 100 parts contained 10 carbonic acid, rained, . , 4 oxigen, 86 azote, 100 In this experiment it is remarkable, that the air which had been so often through the lungs should only have furnish- ed 10 per cent of carbonic acid, while the air which passes them but once contains from 8 to 8'5. Here the oxigen had lost 7 from L21; and the azote had gained 7 upon 79* We knew by previous experiment*, that every cubic inch of carbonic acid gas required exactly a cubic inch of oxigen for its formation ; the ten parts of carbonic acid may there- fore be reckoned as oxigen, which would make the constitu- tion of * See the experiments on carbonic acid in the Society's Transactions, •r our Journal, tol. XlX, p. 223. the 'CHANGES PRODUCED' IN AIR BY RESPIRATION. }g\ the gas after the experiment < g« o. te whereas before the experiment it was < ~ oxigen, azote. Now we did not suppose the residuum of 86 to be all Residuum azote, though 79 might be ; therefore seven parts appeared to have been added by this unnatural mode of respiring, and we conjectured the addition might be gaseous oxide of carbon. To ascertain this, we put 40 parts into a flint stopper bot- tle, and nearly tilled it with about 100 parts hyperoxigenized muriatic acid, procured as before, and recently prepared; the stopper being put in, over distilled water, we plunged it into quicksilver, and filled a second bottle in the same way, as a comparative experiment. We next procured some pure azote, by absorbing the oxi- Ifyperoxigem- gen from a portion of atmospheric air by the saturated green zefl niuriatic ii, » • i ii. i „ acid gas has no sulphate and simple green sulphate as usual ; 40 parts ot acion Up0n this azote were mixed with the same proportion of the acid azole» gas as in the other experiment, and the whole suffered to stand for forty-eight hours; at the end of this time the azote was examined, by washing it first in distilled water, and af- terward in the eudiometer with the tests for oxigen ; and ' there were still exactly 40 parts left ; proving that the hy- peroxigenized muriatic acid gas has no action upon azote. We then examined the bottles containing the residuum The residuum from the air that had been so often respired, and found that azote< it had not experienced the slightest change; it was therefore plainly azote; and on reflection, it occurred to us, that if a certain proportion of oxigen had been absorbed or lost in any way,while the azote remained unaltered, there must be an increased proportion of the latter. Now we knew exactly both the bulk and the constitution Of the air before the experiment; but it was impossible to know the bulk or volume after the experiment otherwise than by calculation. The 300 cubic inches of atmospheric air before the expe- riment lOt CHANGES PRODUCED IT* ATH BY RESPIRATION riment contained 21 oxigen and 79 azote in 100 parts, mak- ing the total quantity of oxigen 63 cubic inches, azote 237 300 The lungs ab- Now if the lungs be capable of fixing permanently any sorb little if .d *u .. u •* u • / any azote, azote from the atmosphere, it appears by our experiments, that the quantity must be very minute, seeing that in the 1 1th, 12th, and 13th experiments, it did not disturb the pro- portion of azote, as shown by the eudiometer; we shall therefore in the present instance assume the volume of azote after the experiment at 237 cubic inches, as before. But after the experiment, every 100 parts consisted of 86 parts azote, and 14 oxigen, either in the form of carbo- nic acid, or free. 86: 14: : 237: 38*53. Therefore the total quantity of oxigen left after the experi- ment would have been 38*58 cubic inches. Then 237 azote -f- 38*58 oxigen =: 275'58; the quantity of gas after respiration would therefore have been 275*58 cubic inches. 300 — 275*58 = the loss of oxigen, or 24*42 cubic inches. Oxigen ab- It appears, therefore, that 24*42 cubic inches of oxigen had r«prrat?on.ing been absorbed by the sys*em under the circumstances of this experiment, t Reviewing the 14th experiment, it appears, that the ga» after respiration contained 85 per cent azote, and 15 per cent oxigen, either in the state of carbonic acid, or free. State of the State of the Air be/ore the Experiment, air in exp. 14. 300 — 237 azote -f 63 oxigen. After the Experiment, 85:15::237:41'82. The total quantity of oxigen after the experiment appear* to be 41*82 cubic inches. Then 237 azote -f 4182 oxigen = 278*82. The CHANCES PRODUCED IN AIR BY RESPIRATION. ] QJ The total volume after the experiment appears to be 278*82 cubic inches. 300 — 278-82 zz 21-18. The loss of oxigen in this case was 21*18 cubic inches. Oxigenab- " sorbed. We are disposed to consider the 1 1th as a standard expe- Accordin riinent relative to carbonic acid gas, because the quantity of experiments, air respired in a given time is pretty near the average of the ab0Vfc }* oz- •> ■ r . & •' , • , troy of carbon first ten experiments; and because it very nearly agrees with emitted from the statement of Professor Davy. In this experiment 292 the ,unf*s daily, r. a , . ., y. • nr • i and395i?4cub. cubic inches or carbonic acid gas were given oft in eleven inches of oxi- minutes; the barometer was 30*4, the thermometer 50°, the 8en gas con- volume being calculated at the mean, viz. barometer 30, thermometer 60°, will be 302 cubic inches given off in ele- ven minutes, or 39534 cubic inches in twenty-four hours, supposing the production to be uniform during all that pe- riod; and as 100 cubic inches of carbonic acid gas weigh 47*26 grains, 100 : 47*26 : : 39534 : 1868376; the weight of the carbonic acid gas amounts to 18683.76^ grains; and estimating the carbon in it at 28 parts in ]0Q> according to Lavoisier, or 28*60, as calculated in the expe- riments on diamond, recorded in the Society's Transactions, 100 : 28*60 : : 18683*76 : 5363*55 grains; it will follow, that 5363*55 grs. or aboye 11 oz. troy of solid carbon, are emitted by the lungs in the course of twenty- four hours; and that 39534 cubic inches of oxigen gas are consumed in the same time, £ut when we consider, that in %ut this more respiration perfectly natural a much smaller quantity of air than the com. can come in contact with those parts of the lungs calcula- mon aTeraKe' ted to act upon it, the proportion of carbonic acid gas given off in natural respiration ought probably to stand considera- bly lower than in the above estimate; but at all events it will be very considerable. Sixteenth Experiment, Having made so many experiments upon atmospheric air, we now proceeded to ascertain the effects produced menu Vol. XXII.— March. 1809. O upon 394 CHANGES PRODUCED IN AIR BY RESPIRATION. Oxigen gas re- upon oxigen gas by the process of respiration. The water epired. gasometer was filled with oxigen gas made from the hyper- oxigenised muriate of potash by heat, care having been taken to clear all the tubes, &c. as much as possible of com- mon air, by forcing a quantity of oxigen gas through them. One hundred parts from the water gasometer being treated with the usual tests in the eudiometer, a residuum of only 2*5 was left; so that 97*5 per cent were pure oxigen, and the rest azote. Fulse quick- The register of the water apparatus being noticed, and cne<*> the operator having prepared himself as usual by a forced expiration, began to respire; his pulse was 72; and at the end of 9 minutes and twenty seconds, the experiment. was concluded by a forced expiration, when the pulse was raised to 88. Barom. Therm. Time. Faht. 29'5 53° 9'20" and natural The operator felt a general glow over the body to the heat increase . ^^ extremities, with a gentle perspiration; this however went off in a few minutes, and no remarkable deviation from the ordinary state was experienced. Component . A portion having been saved, as usual, from each of the CmiNri'ieM mercurial gasometers, for an average, 100 parts contained 1 1 carbonic acid, Cubic Inches )f oxig-en gas inspired. Cub. Inches expired. Deficiency. 32f»0 3193 67 expired gas. 6 azote, 100 The examination repeated gave the same results. Calculation for Carbonic Acid, 100: 11:: 3193: 351-23, consequently* 351*23 cubic inches of carbonic acid ga§ were formed in 9' 20", or 37'64 cubic inches in a minute. More c*rboni$ Were it is plain, that a greater quantity of carbonic acid acid formed, was formed from oxigen than from common air, in the same CHANCES PRODUCED IN AIR BY RESPIRATION. • „ \x)£ -time, and hence we infer, that one use of azote is to regu- ^se of ?zoto late the quantity of oxigen, which shall be taken up in the act of respiration. The gas inspired was 320-0 cubic inches, and of this 2*5 per cent were azote. ' 100:2*5:: 3260:81-50. The total quantity of azote in the gas inspired wai therefore 81*50 cubic inches. The quantity of gas expired was 3193 cubic inches, and of this every 100 parts contained six of azote. 100:6:: 3193 : 191*58. The total quantity of azote in the gas expired was there- fore 191*58 cubic inches; but the total quantity of azote before respiration was only 81*50. 191-58 — 81*5Q= 110*08; The azote ap- « . . , iiiii n parently in- therefore 110*08 cubic inches were added by the process of creased during respiration, beside what little remained in the lungs after respiration, the experiment, Calculation for Oxigen* The 3260 cubic inches of gas inspired contained 81*50 Calculation of azote. the oxigen. 3260 — 81*50 2! 3178*50, and consequently the pure oxigen was 3178*50 Cubic inches. The 3193 cubic inches of gas expired contained 83 per cent of free oxigen, and 11 per cent ip> carbonic acid gas, making together 94. 100: 94:: 3193 -.3001*42, The oxigen gas, found after the experiment, was therefore 3001*42 cubic inches, and deducting this from the oxigen before the experiment^ 3178*50^3001-42 5= 177*08. It appears, at first sight, that 177*08 cubic inches of oxi- Portion mi«s- gen were missing, but great part of this may be accounted *ng' for, by adverting to the state of the lungs after the experi* merit. 0 2 . The ]£5 * 'CHANGES PRODUCED IK AIR BY RESPIRATION. The add -ion The addition of ]10#08 cubic inches of azote we consi- Jrom^thTaTr in der as arisinS fro,n that portion still retained in the lungs, the lungs. notwithstanding the forced expiration at the beginning of the experiment: ;ind con dering that in the 14th and 15th experiment, where the same air was repeatedly breathed, the proportion of azote was in the one case 85, and in the other 86 per cent; it seems fair to presume, that the resi- dual air contained in the lungs after a forced expiration may amount in 100 parts to not more than 16 oxigen and 94 azote. Any one who reflects upon the structure of the lungs, and the minute ramifications of the extremities of the bronchial vessels; when he also < ousiders, that those parts of the lungs wih which the air comes into contact, if spread our, would present a surface equal to that pf the su- / periicies of the whole body; aud lastly, that this vkcus is so exceedingly spongy and porous, that when once inflated, it is ever after impossible by ordinary mechanical means to expel the air completely ; he will easily perceive, not only that a large portion of air must remain for a considerable time in contact with the internal surface of the lungs, where it is liable to lose a portion of its oxigen, but also that the residual quantity of air in the lungs, after the most violent attempts at expiration, may be very considerable. It is to this circumstance, that we attribute the excess of azote in the experiments upon oxigen, and pretty deep inspirations of this gas having been made during o/<20", the azote must have been in great measure displaced. Admitting then, that the air contained in the lungs, before the experiment, consisted of 16 oxigen, 84 azote, and at the conclusion of the experiment of 94 oxigen, 6 azote, we have azote at the beginning, 6 x • azote at the end. 100 6 x 84x + 100 = » 100 100 A 84* 6x uo = I^-!b-oor'84x^'o6* = ^ 110 ,. • ?~ ;^Tor 141 cubic inches; y© Therefore CHANGES PRODUCED IN AIR BY RESPIRATION. 197 Therefore upon this calculation it appears, that 141 cubic State of the inches of gas remained in the lun«;s after a forcible attempt ,hc experi- at expiration; then the state of the lungs before the expe- menr', % riment must have been 118-44 azote, 22*56 oxigen. 141 And after the experiment, 132*54 oxigen, 8*46 azote. and after. 141 Calculation on total Quantities. Azote before the experiment contained in the lungs Azote after the experiment, — found by the tests, — - — contained in the lungs, 81*50 cubic inches, Calculation oh 118-44 the whole quantitj«. 199*94 191*58 8*46 200*04 Oxigen before the experiment, 3178*50 ' contained in the lungs, 22*56 Oxigen after the experiment, Found by the tests, Contained in the lungs, 3201*o6 3001*42 132*54 » ■ " i m 3133*96 Total of oxigen before the experiment,3201*o6 Total of oxigen after the experiment, 3 133*96 Difference '^'lO The deficiency noticed in the experiment was 67, supposing D fi • t that the lungs were brought to the *ame gtate after as beiore oxigen. the \g$ CHANGES PRODUCED IN AIB BY RESPIRATION. the experiment; but granting that this was not the case, and that at the close of the experiment the state of the lungs was 141 +67- 208, still our approximation will come within four or five cubic inches, for the azote contained in the sixty-seven missing would be only about four cubic inches. We are aware, that, the temperature of the lungs being 97» while that of the gas wa^53°, the 141 cubic inches would occupy a space equal to 154 cubic inches; but this residual quantity must be greater or less according to the exertion made, and also probably according to the state of the muscular fibre at the time. Seventeenth Experiment. menu eperator. 17*. e«pen- ^jie waf.er M CHANGES PRODUCED IN AIR BY RESPIRATION, and after the experiment. Contents of the Lungs after the Experiment. 12*43 cubic inches of azote, 213-57 oxigen, 226 lated. Calculation for Oxigen. Oxigen calcu- 3420 — 85*50 n 3334*50 original oxigen, Add 36* 1 6 in the lungs before the experiment^ 3370*66 i tota* °iuant'ty ?f oxigen before \ the experiment. After the Experiment. 100 : 66 : : 250 : 165 oxigen in No. 1. 165 100:82 :: 168:137*76 -. in No. 13. 137*76 100 : 81*5 : : 2944 : 2399 '36 in mixt. 2 to 12. 2399*36 in carbonic acid 396*78 1 in lungs after expt". 213*57 3312*47 3370*66 original oxigen, ■ ■ 33 1 2*47 after experiment, 58*19 deficiency. The observed deficiency in this" experiment was 58. The deficiency in this case, and in the former experiment with oxigen, though comparatively small, when contrasted with the quantity of gas respired, is larger than the average with atmospheric air ; it seems probable, therefore, that a portion may be detained in the system. It must be remem- bered, that what we call residual gas is not only that con- tained in the substance of the lungs, and in its appendages, but also that contained in the fauces and mouth. Deficiency. lftth experi- ment. Barom. Therm. Eighteenth Experiment. Cub inches Cub. inch Time. ofoxg?ngas exi;)il.ed Deficiency, inspired. * 30*15 70 8 45 3130 3000 70. The operator breathed as usual, after having made a strong effort to exhaust his lung9 ; his pulse before the ex- eriment CHANGES PRODUCED IN AIE BY RESPIRATION. 203 periment was 84, the thermometer under his tongue 98°: after the experiment his pulse was 96, and the thermometer Effects. under fits tongue still 98° ; the same gentle glow and pep- spi ration was felt as in the other experiments on oxigen ; a portion of the gas was saved from each of the mercurial gasometers, and their amounts were as under: 196 228 284 294 248 280 7- 8. 9. 10. 11. 12. 258 250 304 223 223 Results. ;o6o No. 1, tried by itself, contained in 100 parts, 9 carbonic acid, 22 azote, 69 oxigen, State of the expired aw» 100 No. 12, the last, contained in 100 parts, 12 carbonic acid, 5 azote, 83 oxigen, 100 On account of an accident we cannot give the proportions' contained in 2 to 10; but the contents of the first and last gasometers confirm the former experiments, and shows that the proportion of azote continues to diminish, as the expe- riment proceeds; and also that there is a larger proportion of carbonic acid given off when oxigen is employed, instead of atmospheric air. In this recital of experiments, which have occupied a con- Leading facts. siderable portion of time and attention, we have endeavoured to give a plain statement of facts, from which every one may draw conclusions for himself; we shall here, however, take the liberty of briefly recapitulating the principal of those1 facts, £Q4, CHANGES PRODUCED IN AIR BY RESPIRATION. facts, and submitting what seems to us the most obviot "3 inferences. No water fonr.- |, It appears that the quantity of carbonic acid gas emit €.-*'*dmthe UUgS* ted »s exactly equal, bulk for bulk, to the oxigen consumed and therefore there is no reason to conjecture, that any wa- ter is formed by a union of oxigen and hidrogen in the lungs. Carbonic acid 2. Atmospheric air once entering the lungs returns fcrtaed. charged with from 8 to 8 5 per cent of carbonic acid gas ; and when the contacts are repeated almost as frequently as possible, only 10 per cent are emitted. The 12th and 13th experiments prove, that, when the inspirations and expirations are more rapid than usual, a larger quantity of carbonic acid is emitted in a given time, but the proportion is nearly the same, or about 8 per cent. The proportions of carbonic acid gas, in the first and last portions of a deep inspiration, differ as widely as from 3*5 to 9 "5 percent. Average pro- 3. Considering the 11th ns a standard experiment, it ap- portions, pears, that a middle sized man, aged about thirty-eight years, and whose pulse is seventy on an average, gives oft' 302 cu- bic inches of carbonic acid gas from his lungs in eleven minutes; and supposing the production uniform for twenty- four hours, the total quantity in that period would be 39534 cubic inches, weighing 18683 grains; the carbon in which is 5363 grains, or rather more than 1 1 oz. troy. The oxigen consumed in the same time will be equal in volume to the carbonic acid gas; but it is evident, that the quantity of carbonic acid gas, emitted in a given time, must depend very much upon the circumstances under which respiration is performed; and here it may be proper to' notice, that all the experiments were made between breakfast and din- ner. Under some 4. When respiration is attended with distressing circum- circumstances stances, as in the 14th and 15th experiments, there is reason oxigen absorb- ed, to conclude, that a portion of oxigen is absorbed ; and in the last of these experiments we may remark, that, as the oxi- gen decreases in quantity, perception gradually ceases, and we may suppose, that life would be completely extinguished oji the total abstraction of oxigen. 5. A CHANGES PRODUCED IN AIR BY RESPIRATION. 205 5. A larger proportion of carbonic acid gas is formed Oxigen gas by the human subject from oxigen, than from atmospheric *^ carbonic air. acid. 6. An easy, natural inspiration is from lG to 17 cubic inches in the subject of these experiments, who makes about 19 in a minute; this, however, will vary in different indivi- duals; and perhaps we ought to estimate the quantity of carbonic acid gas, given off in perfectly natural respiration, at somewhat less, and most likely at considerably less, than in the statement above, when we consider, that in short in- spirations the quantity of air which has reached no farther than the fauces, trachea, &c, bears a much larger propor- . tion to the whole mass respired, than when the inspirations are deep. 7. No hidrogen, or any other gas, appears to be evolved No other gas during the process of respiration. sph-attou" **" 8. The general average of the deficiency in the total Deficiency of amount of common air inspired, appears to be very small, the air very amounting only to about 6 parts in 1000, and we are in- clined to attribute it in great measure to the difficulty in exhausting the lungs as completely after an experiment as before it; the first expiration being made into the open air, the last into the apparatus. 9. The experiments upon oxigen gas prove, that the quan- Quantity re- titv of air remaining in the lungs and its appendages is very !ain '-d m th.e , , , . , ,. ,? . * lungs consider considerable, and that, without a reference to this circum- able. stance, all experiments upon small quantities of gas are lia- ble to inaccuracy. Other important conclusions might perhaps be drawn % from the facts related in this paper, but having already tres- passed largely upon the time of the Society, we shall abstain from any farther remarks, until we bring forward a new se- ries of experiments. 2Q6 on comets. V. A Letter on Cimefs, addressed to Mr. Bode, Astronomer Royal at Berlin, Received from the Author. SIR, Occasion of jL OU wished to have in writing the conjectures on the the letter. nature of comets, which I had the honour of mentioning to you in conversation a few days ago. At present however they form but the embryo of a system, fully to unfold which would require studies I have not pursued, particu- larly that of the astronomical history of the*se bodies, and of the opinions that have been entertained respecting them. I cannot refuse, however, to deliver into your hands these rudiments of ideas, relying on your indulgence both with respect to their want of precision, and to the brevity with which I treat the physical principles, on which they are founded; as these principles are more fully exhibited in different works of mine. But I will at least attempt to its subject, explain in a general way the consequences I deduce from these principles with respect to the lumbtous appearances of comets ; persuaded, that, if they contain a single seed of truth, your intimate acquaintance with the heavenly bodies will enable you to discern and expand it. All luminous I shall set out with what the whole of our knowledge of substances nature appears to me to teach .us very clearly respecting the gWe out light substances, that are capable of becoming luminous : this is, inconsequence jjlat t|ie /fo&, which then escapes from them, had entered Of chemical . , ' ° . . . ,. , . ,11 <»fcoro?osi- mto their composition as an ingredient, and is evolved by che m ical decomposition . Light of the ' In applying this principle to the heavenly bodies, observa- Sun from a tion has added one circumstance with respect to the Sun, fluid surround- ' i»g it. which may be extended by analogy to the fixed stars. Dr. Herschel, you know, has discovered, that the light, which issues from the Sun, does not come directly from its solid substance, but from an atmosphere, or some fluid, by which Luminous it is surrounded. Thus this grand phenomenon has been fcbenomena of brought nearer to us as it were ; analogy, though the sub- ject* ON COMETS. 207 jects differ extremely in magnitude, connecting it with the ouratmos- luminous phenomena observed in our atmosphere, such as p the aurora borealis, luminous clouds, and many other lu- minous meteors. All these are so many hiciferous vapours, though of different kinds ; which, being raised in the at- mosphere iu their compound state, and meeting with some- thing to decompofe them, emit the light, that entered into their composition. To determine with more precision what relates to the Proof that th* Sun, we should consider what led Dr. Herschel to the dis- Ijfht.rf the Sun is not covery, that its light did not issue directly from its solid fr0m its body. body, but from an atmosphere surrounding it. This was its changeable spots; a phenomenon, that had greatly per- plexed astronomers and natural philosophers, but which is clearly explained by the discovery of Dr. Herschel, that these spots are the body of the Sun itself, nonluminous, and seen through transparent parts of its luminous envelope. This shows, that, though the light issues from a fluid be- longing to that kind of atmosphere, which surrounds the Sun, this fluid is not the atmosphere itself, but is simply mixed with it ; and this not completely throughout, since there are parts that remain transparent, or from which no light emanates. Another consideration determines this phenomena still }gut it is frona: more precisely. The disk of the Sun, as measured by us, a Per™anent is properly that of its lucid covering, in the edge of which ** Dr. Herschel has discerned gaps, when any large spot ar- rives there. This covering then has a constantly uniform thickness, since we perceive no change in the diameter of the Sun, which is determined by it. Now this is not the cha- not of the racter of an atmosphere, which in the general acceptation »«tureofan of the term, taken from the atmosphere of the Earth, -g a mosP ,ere» considered as formed of one or several expansible fluids, the density of which diminishes in proportion as the strata are / more remote from their base, so that they extend by imper- ceptible gradations to an indefinite distance. In fact, when astronomers have spoken of an atmosphere of the Sun, they have ascribed to it a vast extent. Thus, if the luciferous fluid, that surrounds the Sun, have such a constant thick- ness, and be so well defined, that it has hitherto been taken for «208 0N COMETS. but rather of for tl)e bod of the gun itse]f jt mugt be a j^ of mpQur a stm j>:i of vi- V clouds. which, emanating incessantly from the Sun, always rises to the same height in its atmosphere, and there forms a stratum as it were of clouds, which is decomposed at a certain height, like, the luminous clouds that are sometimes formed in our atmosphere. By this decomposition the light escapes ; and the substances, with which it was combined, must form some kind of dew, that falls back again upon the v pots rat e gun> Row the transparent spaces, through which we see the opake body of the Sun, are parts of,its atmosphere, into which the luciferous vapour does not ascend, or where, when it arrives there, it does not find the ingredients neces- sary to decompose it into clouds. The latter case would be Openings be- analogous to what we see take place in our own atmosphere, clouas when through the intervals of the clouds we discern the blue colour of the transparent air. The matter of clouds is there, since, as I have proved, they are formed by the de- composition of the air itself; but in these spaces the ingre- dient, which decompose the air, and which assuredly rises from the Earth, is not present. The same the- This theory of the luminous effects of the Sun maybe to\>XVceles° applied directly to the fixed stars ; and it may also be ex- tul bodies, but tended to other large bodies with some modifications. The ideations aimosPneric effects of every one of the bodies dispersed through space depend on its particular constitution. To the constitution of the Sun and fixed stars are owing the greatness and constancy of the luminous phenomena, by which they are distinguished. But other bodies, from the difference of their constitutions, may produce phenomena of a similar kind, though much inferior in different degrees, more or less rarely, and under different appearances. Our Earth, though of the lowest order in this respect, maintains its analogy by the phosphoric phenomena of its atmosphere ; and there may be many intermediate degrees between the highest and this, the lowest. Cotoet* From this last consideration has arisen my conjecture respecting the nature of come ts ; but to establish it de- mands at least a knowledge of every thing, that has been observed respecting these bodies, which I have not studied. What I have the honour to lay before you therefore, Sir, * you 0% fttiwnfct ' 209 j?ou will Consider only an tfie rudiment* t>£ ideas, which ob- servation and reflection may perha;^ herrufteijeoniiriori. I have laid it down as a principle, that the li<>/tt which Their light is h i i • i )• i /•"" # from some che* emanates irom phosphoric bodieB can arise only jroui a tie* mxCiX\ decom- iomposition, which liberates this light from its combination portion, with other ingredients, and which must be induced and in- fluenced by preceding chemical actions on these bodies. This general principle is deduced from, the experience of all the luminous phenomena, that are exhibited in our chemi- cal processes, and all that we observe to take place sponta- neously on our globe: ami this is all we can refer to the other large bodies in the decreasing scale of these effects, from the Sun and fixed stars, the light of which is so in- tense and permanent, to the phosphoric phenomena of our atmosphere. Thus we can determine nothing with respect of the natureof to the constitution of these bodies, the nature of the che- whic.hweknov» nothing. mical processes that extricate light from them, the periods in which these effects must be reproduced, or lastly their different appearances when they are produced. Here then we tind many causes of uncertainty in the application of this principle to the phenomena of comets; and accordingly every thing I have to say on the subject must be vague and hypothetical. ♦ I conceive, that a great number of bodies revolve round Small bodies the Sun at cjjfferent distances, and with different motions ; revolve round which from the smallness of their size, and more especially ^nfiw vSe from the nature of their surface, cannot be rendered, visi- ble to us by reflection of the solar rays ; but which at cer- tain times, or under certain circumstances* are capable of producing luciferous vapours. Let us suppose, that a certain degree of proximity to the their luml- Sun is a circumstance determining either the production or nousnes? Ms the decomposition of these vapours; in other words, that ueames/to the the intensity of its ra#€ is the chemical cause, that induces Sun- the luminous effects. I have been led to this idea by a Phenomena of phenomenon observed in our experiments, which displays the Bolognian some analogy with the supposition here made : certaiu bo- Phos^horul» dies recently calcined, or calcined anew, such as oyster shells and the Bononian stone, after having been some time exposed to the rays of the Sun, are luminous in the dark* Vol. XXII— March, I809. P JEuler 210 #n f6*tE»r£" Euler imagined, that he could draw from this phenomenon an argument against Newton's theory of the emission of light, and in favour of his theory of vibrations : conceiving, that the effect of the rays of the Sun on these bodies was toprodueein them vrhrathns, which continued for some Light not a timc> Qn the contrary i deduce from it an argument mili* f my respect, &c. Berlin, 2 June, 1799, ^ XII. 4n Example of the Utility of a Series in finding a Fluent. By a Correspondent. To Mr. NICHOLSON. SIR, T sometimes happens, that great mathematicians give Difficulty of dU themselves no inconsiderable pains to untie a knot, which rect solutions, they might cut with ihe greatest ease. As an instonctvof this 214 UflLITY OF A SERIES IN FINDING A FLUENT. this, I beg to offer you a detenu i nation of a fluent, which seems to have been considered as presenting some difficul- ties scarcely to be overcome. The equation to be resolved is this ; fx y x */ [x"3, -\- y%) zzz mxj: hence, by squaring both sides, we have [{fxyx)* -m*x*)j*+(fxyx)*x*=0, and [(fxy *)* — m% **] |s -f ( fi y *)* =z0. Put y - a ± b .r2 + c a4 + d J + . . . , then /a- tf ft TZj ax% + $ b x4 + ^ c x6 \- . . .; of which the square may be called Aa,4+ Ba6+ C .i8 -f . . . : again, ~ -3 2 6 .r 4* 4 c x2 + 6 r/ xs -\- . . . , the square of which may be called a, x* -f # a-4" -J- y .»6 -f- . . . ; then, by multiplication and substitution, our equation incomes (A — * m*j *4 + (A * 4- 1) — I-: mxj .r6 + (A /3 -f- I> * + C — y »*j x* + . . . rrO; whence, by the general taw of in;iniie series, An: «wa, Aa-r- B = £>»*, A/3 f li* + C = ym% ..., and ei zz—z, j3z r •, and so forth; but, by actual invo- m nr lution, we find A — I a*, B — £ a b, C — £ « c 4- TV b%, . . . , and again a = 4 bz, (3 — 16 b c, ? — 24 6 J + 16c1,..., , , . * /3 y — l6cc £ — 48cd whence 6 = \/ -— , c — -— , a zz — , ezz ., 4 166 24 32 and so forth; and finally, by reduction, we have b zz 4 w C = 68+~-, d-2b* + ~+1^r-^ and ezz5b^ 10W 18/H 5?0;w 35&5 f 41 63 ■ i , . .. . !* 1- — r 4 — -—rr — = ; and in the case where a be- v32 m J 152 m* 30864 m3 comes extremely small, so that its higher powers may be Mglccted. c a jjj, d = g^, « = £-, and/=^. If, in particular cases, beside the general equation, we have a determination of the value offxyx, for instance fxy x zz nx, we may obtain an equation between x and a, whence either of ihem may be found from * he other; that is, \ax -f- \ bx* + i c*5 + • • • — n: hence, if x becomes very 6mall, a zz.^—\ and if a is evanescent, -pli-f j~t~ X5 x7 \ 4 5V. 4* m* + 4. 2\ 4*. <>> m3 + •'•;=»• - For HI 5T.IUTY OP A SERIES IX nNDfl^ WW&KW 215 For example; let m =: yfey, and gi zr T^7; and let a be Examples, fust *&: tneu * VVH* become, £, c := 3-14, rf = 20*5, and e — 76*7 ; and supposing x zr '3, the equation for n wil) be- come fo% by the correct series, and y^ by the approxima- tion : then in' order to reduce n to its true value, we may may make xyx' ~ [n x)' 3d x rit very nearly, and x = ^-; but y is found, in this case, •074, and x 800 X *074 01014, whence x is accurately '2898 : or, x being *3, a will oua be nearly (jTJ7) X '005=: '0044, by the approximation. In the second place, let a be TV • then b will be £ cm 46*875, d = 1237, and e — 47200 ; and suppose x — £ ; then n bei- comes *00382, ri zz '00007, and x corrected «}104. For a third example, if x be \, wre may find an approximate va- lue of a by the second series, which is *0156; and this be- ing necessarily somewhat too large, we may assume a zr •015, whence n is found '00371, find n being '00004, a will be nearly — n, or '00016, and a, corrected, '01516. In the n first and third examples, the calculations of an eminent mar thematician on the continent, deduced nearly from the same data, have given fpr a, instead of -0044 and '0152,, '0038 and '0136; while some very accurate experiments had long before made the results '005 and -015. If we wished to investigate the properties of the returnv other eases, ing branch of the curve, of which x and y are the coordi- nates, it would be necessary to apply a proper correction to the fluent/ x y * ; another form of a similar curve might also be obtained by substituting p — y fory; and when x be- comes infinite, we find, by a different mode of calculation, beginning from the other end of the curve, ~ x "£ + v{pp— yy\ I am, Sir, Your very obedient servant, \3 Feb. 1809. E.F. G. H. -VII. ■ m METWOO OF CULTIVATING THE AMERICAN CRANBERRV VII. An Account of the Method of cultivating the American Cran- oerry, vaeci rii um Macrocarpum, at Spring Grove. By the. Right Hon. S ir Joseph Banks, Bart. K. B. P- R.S- Cranberry cul tivated with success. Supply from wafer. Artificial island. HE American cranberry, the vaccinium macrocarpum, has for some years been cultivated with success at Spring Grove, and as the fruit of it is now become an object of some im- portance in the economy of the family, a short account of the management of this unimproved plant will it is tobe hoped pro* e acceptable to the Members of this useful Society, and not uninteresting to the Public at large. For the better understanding the intended communica- tion it is necessary to premise, that a spring rises in a small grove within the precincts of Spring Grove, which is no doubt the origin of the name; this spring is carried in leaden pipes into the house, to which it affords an ample- supply ; the waste water is suffered to run through a small basin and a pond in the pleasure ground, before it escapes to Smallherry Green; to this constant supply of fresh water, though it is very small, the great luxuriancy, with which wa- ter plants of all kinds suitable to this climate succeed in the pond, is no doubt in some degree to be attributed. In the middle of the basin, a small island has been /orm- ed, by supporting a box of oak upon posts driven into the bottom; in the centre of this pond, the waste water which used before to issue through a fountain, is suilered to flow in the form of a spring, which rises into a large shell of the chama gigas, perforated for the purpose, imitates very well a natural spring, and gives in hot weather an appearance of freshness and coolness, very pleasant to those who walk in the garden. The oafc box, which constitutes this artificial island, is circular, 22 fee in diameter, and 13 inches deep; the botr torn is 5 inches undei the surface of the water, and bored Jrans. of the Horticultural Society, vol. 1, p. 75. through METHOD OF CULTIVATING THE A'M'EUf CAT* CRAN BERRf. Q J^ through with many holes; on this a layer of stone* and rubbish was hrst placed, and upon that a cohering of bog earth, brought from Ifounsiow Heathy which together are 5 inches below and 7 inches above the surface of the water of the ba- sin ; in this bed of black mould, a variety of curious bog- Bog plants, plants were placed about seven years ago, which flourished in an unusual decree, among these was the vaccinium, which Cranberry. flowered and ripened its fruit the first year. Iu the autumn of the second year it again produced a Runners, plentiful cro>>, and soon after begun to send out runners somewhat resembling those of a strawberry* but longer, and rather less inclined to take root While young ; they did how- ever take root in the winter, and early in the spring threw out upright branches 10 inches and a foot long, on which the flowers and fruit were chiefly placed ; the produce was Fi uit much su- this year gathered, and found to be high flavoured berries, Sported.1 ** very superior to those imported, which have in general been gathered unripe, and have become vapid and almost taste- less bv long soaking in the water, in which they are packed for carriage. It was now determined to consider the American cranberry Cultivated for as an article of kitchen garden culture, and to give up the the kitchen, whole of the island to it, which in a few years it entirely co- vered by its own runners, without any fresh plants being put in, and this bed, with the addition of some hanging boxes receding from the centre to the sides, produced, in the year 180G, 23 bottles of very fine cranberries. In the year 1805, a bed was made on the side of the pond Extended to a 20 feet long and 5± feet broad, by a few stakes driven into ^d^>' ll^idc the bottom parallel to the side, aud lined with old boards; the bottom of this was filled up with stones and rubbish, and on these a bed of black mould. 3 inches above and 7 inches below the usual surface of the water, was laid : this was planted with cranberry plants, many of them having been rooted in a hot bed, in which they thro e most vigo- rously. In this autumn, 1807, the bed produced a crop, whirh, added to that of the island, afforded a supply for the family of 5 dozen bottles of cranberries, beside a small bas- ket reserved for present use. The total contents of the two cranberry beds is 32G square feet; the quantity of land em- em plowed g]g ANIMAL MATTER IN fOSSlLS. ployed for raising strawberries at Spring Grove is, after the divisions between the beds have been deducted, o()45 square feet; the beds necessary to give a sufficient supply of cran- berries for the family did not therefore occupy quite £th of the space allotted to sir aw berries. Accident su»- ^ne society will, \ jiope, forgive this detail of the origin 3 are more showy than the dahlias; and they possess the additional merit of being'produced at a season, when most others are decaying; nevertheless, it: will appear in the subsequent pages, that by a little manage- ment these plants may be made to blossom at a much ear- lier period: and that in vallies, or low situations, where our autumnal frosts frequently cut them off early in October, it is the only method of obtaining their flowers at all. X am more emboldened to offer these results of my own experience to the Horticultural Society, as they have turned out very different to what was expected from the hints thrown out upon this very subject by one of the first gardeners in the world. History of The earliest account I am able to trace of these plants, thern, which are all natives of Mexico, is in Hernandez' History of that country, published in lb'51, where two species are figur- First mention- ed. He says that the first grows in the mountains of ^by Hernan" Quauhnahuac, and is called acocotli by the inhabitants; that it has leaves composed of five leaflets, some of which are sinuated, slender peduncles, with pale-red stellated flowers; that the roots are tuberous, strong and bitter in taste, and, according to the fashionable jargon of his time, hot and dry in the third degree ; that an ounce in weight, taken internally, is a powerful medicine, alleviating pains in the bowels, expelling flatulence, increasing the urinary dis- charge, promoting sweat, strengthening cold languid sto- machs, excellent against the colic, resolving obstruction?, and dissipating tumours if externally applied, This is clearly the pale red variety of dahlia sainbucifolia. The second he calls acocotli ligustici facie, but gives no descrip- Trans, of the Horticultural Society, vol. I^p. 84. tjo* CULTIVATION OF THE DAHLIA. 225 -tion of it: the figure however, though destitute of flowers, leuves no doubt, fhat it is the species called dahlia bidenti- folia in Paradisus Londincnsis, and from the size of its fo- liage most probably the orange coloured variety. Mr. Thiery Menonville, in the interesting detail of his T.Menoimlle. journey to Guaxaca, published in 1?87> is the next author, who to the best of my knowledge has noticed any species of dahlia. It is well known, that this botanist was em- ployed by the French Minister, to steal the cochineal insect from the Spaniards. In this dangerous mission, he tells us, that having entered one of the gardens in the suburbs of that city, adjoining to a plantation of nopals, upon which the insect feeds, he was struck with the beauty " d'une as- " tere violctte et double, aussi grande que cefles de France, ** mats produite par un arbuste tres sembl able pour lesfeuilles " pinnees a notre surcau." From the violet colour of the flower, I am inclined to think, that this is the species which I have called dahlia sphondyliifolia. The third author, who has written upon these plants, is €avanilles. the late Abbe Cavanilles. From a semidouble variety of dahlia sambucifolia, which flowered at Madrid in October 1790, he in the first volume of his Icones, published in the following January, first defined the characters of the genus scientifically, naming it in honour of Andrew Dahl, a Name. Swedish botanist, with the specific title of pinnata. After- ward, in the third volume of the same work, he makes us acquainted with two more species; his rosea, which from diis ambiguous title has been confounded both here and at Paris with his first ; and his coccinea, no less absurdly so .denominated, its ligulated florets varying from yellow to -orange, but never assuming a scarlet tint. My reasons for adopting his generic, bvit none of his specific names, will be" given hereafter, and are conformable to the usage of Linne in those classical works Flora Lapponica and Hortus C'liffortianus. These three dahlias having been sent to Paris from Ma- dridhy Cavanilles in 1802, a very ample memoir with co- loured figures was published two years afterward by Mon- Thouin. sieur Thouin, in that celebrated national work, the Annates jdu Museum d'Jiistoirc Natureile, and he makes the fourth Vol. XXII.— March, 1809- Q writer . 226 CULTIVATION OF THE DAHLIA. Description of writer upon them. We there learn, that they are peron- e P an ' nials, losing their stems at the approach of winter, which do not push forth again till late in spring; that their roots con- sist of fleshy tubers disposed like those of the asphodel, though less numerous; that on their arrival they were planted in large pots of substantial earth, and protected from frost under a frame ; that the stems grew little till the great heats of summer commenced, wheu they lengthened rapidly, and flowered in the end of autumn. Monsieur Thouin then describes the first, his dahlia rose, as attaining seven feet in height; leaves opposite, composed of from 5 to 9 leaflets; flowers about the size of a China aster ; ligu- lated florets commonly 8 in number, pale red inclining to flesh colour; of which all the earlier flowers ripened seeds. Tug second, his dahlia ponceau, was only four feet high ; stem slender, covered with a tine meal ; leaves doubly pin- nated, and pale green ; flowers smaller than in the two other species; ligulated florets from 8 to 9, red orange colour ; this flowered later, and did not ripen seeds. The third, dahlia pourpre, he erroneously supposes to be Cava ni lies' dahlia pinnata, and thinks it greatly superior in beauty to both the others ; the roots of this he observes are covered with a violet coloured cuticle ; stems about five feet high; leaves often produced in threes ; flowers semidouble; ligu- lated florets of a rich violet purple, approaching that of the pansy, or still more like the fruit of the prune de Monsieur, which on their inner surface reflect the light variously (eha- toyante) like a shot silk ; it flowered the latest, and only ripened yery few seeds. His mode of After paying some handsome compliments to Cavanilles cultivation. for sending, and to Dr. Thibaud for bringing the roots from Madrid, this candid and judicious gardener proceeds to state what, he conceives, will be the properest mode of treating these plants. He remarks, that, being newly ar- rived, with all the original habits contracted in their native • climate, it will only be after a lapse of years, that their cul- ture can be thoroughly understood ; and that if he antici- pates any directions on this head, it is rather to excite the attention of others to the subject, than lay dpwn tixtd and positive rules for their conduct, From tl^ magnitude of the TULTIVATION OF TI1K DAHLIA* ^^7 the roots, the abundant foliage, and rapid expenditure of «ap in these plants,, he concludes, that a strong but very rich soil,' nearly ppch as orange trees delight in, will be most suitable for them, with plenty of water in dry wea- ther* Being ignorant of their particular locality in Mexico, he doubts whether they will live through winter at Paris m the open ground, giving his opinion in the negative, for the following reasons: 1st, herbaceous plants so tall and tender are seldom met with in high mouutains, the dominions of winds, snows, and storms; -idly, these plants, when exposed to a temperature of 7 or 8 degrees below zero, turn yellow and sick ; 3dli/, they are late in beginning to vegetate, and require a long protracted autumn to expand their flowers : 4thft/, their roots had been already killed at Paris, by a frost of live degrees in one night. Notwithstanding this unfavourable statement, Monsieur Thouin does not despair of being able in time to change their habits, and acclimate them in France: to this end, he proposes forwarding them in spring with a little artificial heat, and wisely remarks, that our days in summer being longer than in Mexico, a Longer days Sufficient maximum of heat to bring their flowers and seeds *q urgent to _ .-it • greater heat iti to perfection may thus he obtained; that thus barley, which vegetation. in the north of France requires six months to ripen it, in Russia is often perfectly matured in forty days. He then brings instances of two plants from the same country, the marvel of Peru, aud long-Jloivered marvel of Peru, which, though very tender when hri>t introduced, are now become more hardy, the former especially often springing up in their parterres from self-sown seeds. Lastly, he informs us, that Mode of pro- all the dahlias may be increased by seeds, dividing their pagation, roots, or even by cuttings of their stems, though that part js annual; but seedling plants, he remarks, do not flower the first year, and the memoir concludes with some general remarks on the beauty, and ornament, which they will add to our borders or conservatories, in autumn. The fifth author upon this genus, is Professor Willde- Willdenouw, nouw, who in his Species Plantarum most unwarrantably changes its name, under the pretext that another dahlia was already established in dioecia ! This is so far from being ttue, that the description of the Cape plant he alludes to, * Q 2 by 223 CULTIVATION OF THE DAHLIA. by Professor Thunberg, in the Skrivler of Naturhistorie jSetfskabet, 2 bind, did not come out till 1702; nor was the manuscript even read before that society, till April, 1/91, three months after Cavanilles' dahlia had been publish d. I am aware, that there is no general rule without an excep- tion, and that in some cases the right of priority must be given up ; but in this not a shadow of reason for the inno- vation can be offered, a *d as these plants are universally (known, both in our Island, and upon the Continent, by the name of dahlia, much inconvenience will ensue for a time, if the other be adopted: moreover, it would be unjust to Cavanilles, who is dead and gone. 1 roust now venture to give some account of the introducr tion of the dahlias into our own island; when it will appear how rapid iy we nave improved upon the French method of treating them ; and as they have already not only produced a number of varieties with us, but each species requires a somewhat different management, I shall orrer such observa? tions, as i hope will not be found quite useless respecting them. The first species, dahlia sambuci/blia, was introduced into 1st species. this country by the Right Honourable Lady Holland, who Introduction t , , ,. -_ , . , . , . „ .... into Britain. sent tne seeds irorn Madrid in May, 1804, which nave pro- duced several varieties of different colours. For this rear Specific nasie. gon^ j naye rPjectecj ^oth the specific names rosea and purpu- rea, for one that is applicable to both of them. Pinnata, as Monsieur Thouin observes, is equally inadmissible, because many of its leaves only consist of three leaflets ; and a greater number of the leaves of the 2d species being also pinnated, it has already occasioned miich confusion. Though the seeds arrived so late in this country, several of them flowered the succeeding autumn at Holland House, and the variety £ with deep purple flowers was immediately pretty well figured in the Botanist's Repository. By the constant attention of Mr. Buonaiuti, in pressing out the moisture, which is collected among the florets after the calyx closes, a number of seeds were ripened in 1805, and some of these were liberally communicated to me late in the month of April, 1806. I hjid no opportunity of sowing them till the 5th of May, Culture. when they were put iutp two pots of light rich earth, plunged CpLTIVATION OF THE DAHLIA. %%() plunged to their rims in a bed of dung, which had nearly lost its heat, having been made two months. A dozen plants soon came up; and on the fiist of June, being about 5 inches high, as well as very stiff, from throwing dow.i the glasses in the day time, were transplanted into separate pot3 Of 2£ inches diameter. In these they continued three weeks, when two of the strongest were removed without breaking any of their fibres into large pots of very rich mould, with the intention of following Monsieur Thouin's directions minutely; tive of them into pots one size larger, of very rich mould, and tive of them into pots one size larger, of poor sandy mould. All these plants were twice more transplanted into somewhat larger pots before the 10th of August, by which time the two largest were 4 feet high, and theothersnotmuch shorter, though less branched. They were now all removed from the hot-bed frame, having been ex- posed to the open air both night and day the last month ; the two largest into a border of rich earth, but the rest plunged as they stood in the pots, in various parts of the garden, near the walls, but only in west and east aspects, that to the south being entirely filled with other plants. Their stems and branches, as they advanced, were carefully secured from being broken by the winds, and they were supplied with water, whenever their leaves flagged. They F]ovm.in<, all grew rapidly in August and September, but I despaired of seeing any flowers till the middle of the latter month, when almost every branch terminated in a flower, the first of which opened the 7th of October. Soon after others came out; but what is well worthy of attention, the two largest plants, which had been nourished the most luxuri- ously, though placed in the warmest corner, were the latest in showing flowers. One of these, which had at- tained to twelve feet in height, did not expand its first flower tili the 2Qth of October, producing however a plentiful suc- cession till the beginning of December; in the first week of which a violent storm of wind and rain nearly put a stop to its vegetation. All the plants ripeued seeds more or less, and were suffered to remain in the ground with their decay- ing stems uncut, till a frost came, which was severe enough to freeze the borders an inch deep. The morning after, t^ose 530 CULTIVATION OF THE DAHLIA* those which had been plunger! in their pots were taken np and removed into the greenhouse, behind other plants: the two in the ground, after cutting down their stems to about a foot and a half in length, and removing 1 he frozen crust of earth, were protected With a covering of moss and fern about six inches thick. Management " '" 1807, the greenhouse plants were removed into the thekecond open air so earlv as the -JTth of April, and the dahlias at vear. M . ■ . . . ., ttie same time just beginning to push were turned out oi the pots, and planted in very different parts of the garden, as well as in ?ery different soils. Having observed the pre- ceding year, that those which had been confined in the smallest pots and poorest earth not only flowered the ear- liest, but made to a gardener's eye the handsomest plants, being only from 5 to 6 feet high, with scarcely any branches, and panicles of from 7 to 13 flowers; I ordered some of them, to be placed in pure gravel from which all the larger stones had been screened, others in a dry seam of sand which crossed the garden, and others again in rich earth ; they were all supplied with water however during the dry part of Seedling the summer. Beside these, a uumber of seedling plants * were distributed at random in different gardens; and what gave me no little satisfaction, I observed in June, near the large plant of all, a cluster of young seedlings coming u*p from a head which had been supposed rotten, and dug into Flourished the border at its winter cleaning. The result in autumn was best m screen- similar to that of the former year, but with a still more* ed gravel. * * . decided advantage to the plant in screened gravel. Oue of these expanded its first flower the 19th of August, and its last the 27th of September ; all the seeds ripening perfectly : being the dark purple variety f, and planted singly in the middle of an open grass plat, it attracted far more atten- tion than the venerable ch^inyts, magnolias, Cembra pines,* cedars, and ci/pres-es,, rV-i.ets of Peter Collison's labour, which surrounded it. The largest plant of all, against the south eaat side of .the house, in rich earth, had not opened a single flower on the 14th of October, when I left the place; bnt though plants at Holland House, as well as in Messrs. Lee and Kenuedy's garden at Hammersmith, had then been already blasted by the frosty nights, 1 understand it remain- ed CttLTIVAlTON OF THE DAHLIA. 23l ed uninjured, and continued blowing till the middle of Ab- vember, in great beauty. It is necessary to observe, that the Village of Mill Hilt, Mill-hill, where I lately resided, is situate upon a high ridge, at the head of two vallies, in which some of the sources of the little brook, called the Brent, arise; and the garden, in which these dahlias were cultivated, is well screened from the wea- ther by high trees. Being rather above the level at which, the exhalations of the adjacent country pass off, the early autumnal and late spring frosts never reaeh it; at least they have been so mild during the six years I lived there, as never to have cut off cucumber plants, potatoes, french beans, and troperolums, till long after others of the same species had been killed in the vallies. In hoar frosts, the top of Harrow Hill, Bushy Heath, Ehlrcc, and Totlcridge, are commonly seen green, or illuminated by the sun, when the rest of the neighbourhood is white as snow, or obscured in a sea of fog* The medium temperature of this delightful spot, and 1 be- pfigh grounds lieve of most other grounds equally elevated, during the warmer in win- mouths of December, January aud February is considerably valleys, milder than in any valley, perhaps never less than from 1 to 5 (hgrees : in extremely severe frosts, the difference is still more apparent, so that when the cold has been down to 12 and 9 degrees of Fahrenheit's thermometer in London, it has only been 20 and Vo there; and this is likewise proved by the more tender exotic plants still remaining in the gar- den, some of them G'O and 70 years old. The common broad leaved myrtle against a wall there quickly grows to (i feet in height without any covering, ane second sentence, that " it lives con- stantly on dryland," appears altogether inapplicable to any of the diver genus. Lewin, speaking of this genus says, f* if we consider the situation of their legs at the extreme part of the body, and their having scarcely any thighs, we must be convinced, that they were not intended for walk- ing: we cannot suppose therefore, that these birds are in- habitants of the land, but that they breed and live on the water only." In fact* if nature webbed their feet for them to live on drv land, she has done something in vain. XI. On the Gold Mines in the Department of the here, by Heri- cart de Thtjry, Mine Engineer*. JL HE existence of gold mines in France has long been ■tune* known questioned, though old writers have given us the most posi- to the old t'lve accounts of them ; and the auriferous sands have been wt"ers' considered as our only sources of this metal. The want of accuracy in terms, uncertainty of place, vague information, and mysterious air of the mountaineers, who are naturally mistrustful, have long prevented credit from being given to * Abridged from the Journal des Mines, vol. XX, p. 101. the GOLD MIXES IN FRANCE. 0&5 the repeated stories of discoveries of gold mine*?: but when the intendants, by order of the regent duke of Orleans, caused u general search to be made into all the metallic and mineral matters throughout the kingdom; when collections of these substances were formed, and they were carefully described; and when accurate analyses had been made by enlightened chemists; the wealth concealed in the French territories could no longer be Questioned. Dauphiny was Dauphiny one then cited as one of our richest provinces; its mines attract- of tJ)e riehvst , , .. . ,. • i -i mi provinces in ed the attention ot government; information considered till m-mes< that time as vague and uncertain was collected with care; skilful men were employed to examine these indications, and it. was soon found, that Dauphiny really possessed se- veral gold mines, some of which appear to have been known and woi ked in very remote times. The mines are of two different kinds: some affording na- ^wo fei^a! tivegold; others containing this metal mixed or so inti- them. niately combined with different metallic substances, that its presence is to be detected only by the assay. The native gold mines of what was formerly the province Native gofci of Dauphiny are, 1, that of la Gardette; 2,' that of Dor- mincs millouse or la Freissiniere ; 3, those of Orel ; and 4, the au- riferous sands of the Rhone. The mine of Dormiilouse is in the present department of the High Alps, and that of Orel in the department of the Drome. The mountain of la Gardette rises above the village of Mountain of the same name, in the commune of Villard-Eymont, near la Gardette. four miles south of the town, of Oisans, and about six from AUemont. Its miue was included in the circle of mines Mines granted granted to Stanislaus count of Provence, brother of Lewis to,he C(mnt of XVI, by a decree of the council of state in 1776. This mountain, which is 12#0 met. [ 14 10 yards] above Geology of the the sea, and 550 m. [()00 yards] above the town of Oisans, mountain. lias at its foot a perpendicular clitf above 200 rn. [218 yds.] high. Its base is a reddish granite, composed of red feld- spar, green steatitic quartz; and gray mica. Above this is a laminar quartz rock of a blackish gray, the strata of which run SS E and N N YV, and have an inclination of 33°. This micaceous rock, in which the vein of gold is found, Qold vein: is covered by a seco**dary limestone, which forms the whole of 0*g COAL MINE! IN FRANCE. of the upper part of the mountain. This is of a deep blue gray, and contains belemnites and ammonites. The incli- nation and direction of its strata vary greatly, but in general they incline to the north at a greater or less angle, which ap- pears to be determined by the slope of the primitive rock, on which this limestone rests. At the southern extremity of the mountain, below Villard-Eyroont, the micaceous rock is covered by amygdaloid hornstone, which from the decom- position of its calcareous nodules assumes a pseudovolcanic appearance. The vein of la Gardette is quartz in mass, crystallized wherever the siliceous matter has not been sufficient to fill the whole of the vein. It is enchased in gneiss. Its direc- tion is W N W ; its dip to the south, 80° ; its thickness va- ries from CO to 80 or 90 centim. [l ft. 11 inch, to 2 ft. 11 inch.] and upwards. Its length has been ascertained for more than 450 met. [492 yrds.] from the foot to the summit of the mountain. Attempts to The first attempts to work it were made in thebeginniu.^ of the last century by some of the mountaineers, who gave it up for want of money or of skill. In 1733 some re- searches were made by order of the king, but they were badly conducted, and without success. In 17o\5 some of the inhabitants of Gardette attacked it anew, to obtain rock crystal. Their labours were confined to a shaft of 1 1 met. [12 yds.] deep, in which they found some indications of gold, in crystals of eulphuret of lead deposited on needles of quartz. In 1770, after the discovery of the silver mine of Chalanches, one Lawrence Garden tried the vein, and after several days labour he found in the gangue many specimens of gold distinctly marked. These he carried to the found ry of Allemont. Mr. Binelli, its superintendant, assayed them, ascertained the presence of the gold, and paid a visit to the spot; but he could not be persuaded, that the specimens he had assayed were taken from this vein. In 1779 however, Mr. Binelli being succeeded by Mr. Schreiber, Garden car- ried some specimens to this gentleman, who visited the place, and found, that the vein really contained gold. On there- port of Mr. Schreiber, the count of Provence ordered the mine to be explored, and the works were begun in June -work it. SCIENTIFIC NEWS. 237 June 1781, and they were continued with much diligence till 1788. (To be concluded in our next. J SCIENTIFIC NEWS. Wernerian Natural History Society, J\ T the meeting of this Society on the 1 1th of February, Cryolite. Professor Jameson read a short account of tiie oryctognostic characters and geognostic relations of the mineral named cryolite, from West Greenland. Mr. P. Neill read a description of a rare species of whale, Rare specks pf lately stranded near Alloa, in the Frith of Forth. It mea- wiiale' sured 43 feet in length ; had a small dorsal fin ; longitudinal sulci in the thorax ; short whalebones ffanonsj in the up- per jaw ; the under jaw somewhat wider, and a very little longer than the upper ; both jaws accumulated, (at least, considering the bulk of the animal, they might be so de- scribed), the under one ending in a sharp long ridge. From these characters he considered it as evident, that it was the baleinoptera acuto-rostrata of la Cepede, and that that au- thor had fallen into an errour in saying, that this species j never exceeds from 26 to 29 feet long. At the same meeting, the Secretary laid before the So- Great se* ciety several interesting communications. 1. Copies of the snake» affidavits made before the Justices of the Peace at Kirkwall in Orkney, by several persons who saw and examined the great sea snake fhahydrus PontoppidaniJ, cast ashore in Stronsa in October last; with remarks illustrative of the meaning of some passages in these affidavits. — 2. An ac- Toad in a bed count of the discovery of a living animal resembling a toad, c,ay* inclosed in a bed of clay, in a cavity suited to its size, at the depth of 57 fathoms, in the coal formation at Govan ; communicated by Mr. Dixon, of Govan Hill. — 3. An in- Intrepidity of stance of remarkable intrepidity displayed by an old male aa otter* and female otter, in defending their young, although the otter S5$ ejection of British shells. SCIENTIFIC NEWS. otter is generally accounted a very timid animal; commu- nicated by Mr. Luskey, of C red i ton. At this meeting also, Mr. Laskey (who is at present with his regiment at Scotland, and who is well known in the scientific world as an eminent conchologist), presented to the Society a very valuable and well arranged collection of British shell*, and likewise a curious mineral from New- Holland. fcoyal Society. Ammonia con- tains oxigen. ^o hidrogen in potash. Sulphur and phosphorus. Carbon. acid. Boricic acid. Muriatic acid Royal Society. IN the Bakenan Lecture read in December last, before the Royal Society, Mr. Davy has given an account of va- rious experiments on ammonia, sulphur, phosphorus, char- coal, the diamond, plumbago, and the fluoric, boracic, and muriatic acids. The results seem to prove, 1. That ammonia contains oxigen, which he had ven-. tared to infer from facts detailed in his Dakerian Lecture for 1807; and that in the action of ammonia and potassium, it is the ammonia that is decomposed, and that there is not the slightest evidence in favour of the existence of hidrogen, in the metal of potash. 2. That sulphur and phosphorus contain hidrogen and oxigen, and that they are probably combinations of these matters with bases, which have never yet been obtained pure; and that they are analogous in their constitution to the oily bodies, except that these last have for their base6 the carbonaceous element, 3. That charcoal in its purest form contains hidrogen ; and the diamond probably a slnall quantity of oxigen; and that the purest form known of the carbonaceous element seems to be in plumbago, where it is alloyed with iron. 4. That the fluoric acid may be decomposed and recom- posed, and that its basis is analogous to the sulphureous basis. 5. That the boracic acid is likewise susceptible of der composition and ^composition ; and that it furnishes a pe- culiar basis, which is more analogous to charcoal than to any other species of matter. (j. That muriatic acid gas in its common form contains at least one third of its weight of water; and that, when the SCIENTIFIC NEWS. 23.9 the substance is obtained free from water, it is more con- ducting as to elecricity, docs not redden vegelahle bines, and in different combinations detonates violently Willi pot- assium. Whether ihk muriatic basis be separated in these explosions, Mr. Davy has not yet been able to ascertain. In a communication read before the Royal Society, Fe- Nitrogen de- bruary the 3d, Mr. Davy has detailed vanous cxperimeats comP0Sed* on the distillation of substances formed by the action of potassium on ammonia, which he conceives cannot be ex- plained on any other supposition, except that* nitrogen is a compound of oxigen and hidrogen, or that ammonia and water consist of the same kind of ponderable elementary matter. Whichever conclusion may be finally adopted, the decomposition of nitrogen in the process is sufficiently evi- dent. By an errour of the press in the extract from Mr. Davy^s Correction of letter in our last number, 1000 is put for 100. The con- *n errour- text sufficiently shows this mistake; but for greater security I notice in this place, that 100 plates are quite sufficient for decomposing potash. TO CORRESPONDENTS. Dr. ROBERT HARRINGTON, of Carlisle, must al- low me to decline any engagement as to publishing his in- tended communication, till after it may have beeu submit- ted to my perusal. I must also beg leave to say, that neither the threat nor the insinuations contained in the let- ter, which conveys the proposal I have rejected, are, in my apprehension, entitled to notice. I am much obliged by the communication of Mr. Kemp, which I am prevented from making use of, because his re- searches have been anticipated; as may be seen in the 2d edition of my Chemical Dictionary, and in Rees's Cyclo- pedia, Art, Copal. METEOROLOGICAL JOURNAL For FEBRUARY, 1809, Kept by ROBERT BANCKS,Math€tnatical Instrument Maker, in the Strand, London. THERMOMETER. 4 B A ROME. TER, WEA1 HHER. JAN. . • c si Day of 3 < tc v o 2 9 A. M. Night. Day. o> o> X^ i£ 27 48 48 46 46 2.9'51 Cloudy Rain 2S 48 48 50 46 29'59 Ditto Fair $9 46 47 48 45 25)* 26 Fine Rain 30 45 46 48 43 29-32 Rain* Ditto 31 42 42 44 40 29 76 Cloudy Fail- JEB. 1 46 50 52 48 2977 Ditto Ditto g 48 49 51 47 2.0-5 1 Rain Rain 3 50 45 52 42 29*21 Fairf Ditto 4 44 43 46 42 29*45 Ditto Ditto 5 43 43 46 42 2938 Ditto Ditto 6 44 46 43 36 29*42 RainJ Ditto 7 38 35 40 31 29-S9 Cloudy Ditto F 32 33 34 33 29*90 Rain & hail Cloudy 9 * 42 48 50 44 29-39 Ditto Rain JO 47 47 50 44 29*28 Cloudy Ditto 11 44 46 48 41 29'21 Ditto 'Ditto 12 44 48 49 40 28-83 Ditto Ditto 13 44 46 49 42 28-81 Ditto Ditto 14 45 47 49 42 29'26 Ditto Ditto 15 46 46 51 4i 29*70 Rain Ditto 16* 44 47 49 45 29'83 Ditto Faii- 17 46 49 53 44 29-58 Cloudy Ditto IS 48 40 55 38 29 -80 Fair Rain 19 42 46 48 44 29*46 Cloudy § Fair 20. 46 40 50 34 29 27 Fair Cloudy 21 38 33 42 32 (29'97 Ditto Fail- 22 34 38 46 33 30-33 Ditto Ditto 23 44 42 50 39 3010 Ditto Ditto 24 42 42 46 38 II 30-31 Ditto Ditto * Rain, tremendous wind. + At 21 Orion and the Moon brilliant. J At 11 fine, inclining to fiost. | Fine till 8. Halo circumscribing the Moon, indicating moisture. l| During the conflagration of Druiy Lane Theatre, a thermometer hanging cppo:>ue it in r»y Observatory rose o degrees. The distance is nc^r COO yards. Nuhdwnrlfclos- Journal . Vol.JBE /'/ & Aft W? . ,W yf & /_ Jf t}<> JOURNAL OP NATURAL PHILOSOPHY, CHEMISTRY, AND THE ARTS, APRIL, 1S09. ARTICLE I. Plan fur an improved Theatre: by Sir George Cayley, Bart. In a Letter from the Author. To Mr. NICHOLSON. SIR, Brompton Malton, Yorkshire, March 1, 1809. JLn consequence of this second theatrical disaster within P]an for a th^. so short a period, I take the liberty of enclosing, for the use atre. of your valuable Journal (if you think proper), a plan, and letter of explanation respecting it, which I submitted to the proprietors of Covent Garden Theatre some time ago, but which I am just informed by Mr. Kemble has not been able to be adopted in any degree by Mr. Smirke, their architect. If you think the paper worth printing, or any extract* from it (which might be more proper) it is much at your service ; if not, you will have the goodness to re- turn it. As a new theatre will soon have to be built, and Imperfect as the public is so much interested in having it as conve- *"nts mav bc nient a3 possible, publishing a few hints of this kind, how- improve upon' ever imperfect, may call forth others of more value ; and thus at length some good may arise. Vol. XXII. No. 99— April, 1809. R The 242 PLAN FOR AN IMPROVED THEATRE. Theatres are The ancients bestowed grt&t pains upon their theatres, orUnce "*" anc* ^^ are certa,n'y nn object of considerable importance in society. I conceive there can be no difficulty in blending Convenience the beautiful with the useful in the construction of these should be uni- ..... .„ . . . , . , , . . , . ted with beauty buildings, if they do not indeed go so much hand m hand, in them. as almost to be inseparable. You will perceive, that the The principle plan I allude to is constructed upon the principle of apply- stnene^hen the m% a^ tne soun^» tnat can be caught, by the reflecting sur- ▼oice by re- faces of the building, to those parts only of the theatre flecte sound, where t],e direct voice of the actor may prove too weak to be heard distinctly. There should be a note inserted to this effect in some part of the letter, viz. that as no simi- lar sounds uttered in succession to each other can be heard separately by the finest ear, when the interval of time be- No echo would twecn each does not exceed TV of a second; therefore, no in certain li- " reflected portion of a sound that arrives at the ear within mits. less than TV of a second after the direct pulse will make a separate impression, or echo, but will add to the strength of the former impression. Hence, as sound travels about 1142 feet per second, unless the difference between the whole distance travelled over by the reflected pulse and that of the direct pulse be greater than 214 feet, no echo will be perceived. Tn the plan of the theatre sent, the greatest difference of this sort only amounts to 69 feet; therefore, even in this instance, about one half of the influence of the reflected pulse would be exerted in adding to the intensity of the sensation of the direct pulse, and about one half in prolonging a nearly similar impression. I must apologize for writing to you in so slovenly a man- ner: I am much hurried, being just setting off on a jour- ney, and I coneeive, that, unless these hints can appear in your next number, they will be forgotten before another theatre requires planning. In the mean time I beg to thank you for much pleasure and information conveyed to mc by your Journal. I have the honour to remain, Sir, Your obedient servant, GEO. CAYLEY. To PLAN FOR AN IMPROVED THEATRE. To JOHN KEMBLE, Esq. SIR, Brampton, Sept. 25, 1803. SINCE the lamentable accident, that has so lately hap- Theatres pened to the Covent Garden Theatre, the frequent occur- j}^df^££ rence of that event to my thoughts has led me to speculate venience of upon the various improvements, that might be made in the seeing & near- construction of theatres. I have taken the liberty of en- ' g* closing you the following* plan and hints, which I conceive to be worthy your attention, in as much as they state un- doubted principles, which local convenience may more or less permit to be put in practice, but without an attention to which no theatre can be pronounced well constructed. The science of acoustics is perfectly well understood, and the enclosed rough sketch of the internal plan and elevation of a theatre is modified to the principles of that science, in conjunction with giving the greatest possible convenience of sight to the largest number of people the space can con- tain. It is the property of an elliptical room, to collect all the Advantages of sound uttered in one of its foci into the opposite focus by ^e elliptical reflection ; hence, as the ellipsis is a very beautiful curve, and as it is only the parts of a theatre distant from the stage, that require the aid of reflected sound, I have adopted this figure, as the ground plan, Pi. VIII, rig. 1, will show. Here any voice uttered upon the stage at A would be con- centrated at the point B, excepting what is absorbed by entering the side boxes. I have drawn the stage semicircular, and on one side ar- Semicircular ranged the seats concentiical with it. This, I conceive, staSc« would be a material benefit to the observers, but it would Advantages & have this objection, viz. that the seats, if so placed, must disadvantages rise in steps aud have arms to each ; hence the necessary cenu-ica^with allowance of room for the accommodation of the largest it in the boxes persons would be more than necessary for smaller ones; and on no occasion, however pressing, could the advantage be taken of sitting closer. I have also drawn the scenery in a portion of a circle, Scenrs should which would be a most material advantage, both to the circfe*!^1113 ° hearing and sight, if conveniently practicable : and provided double the height of a scene can be had within the build- <24-> PLAN FOR AN IMPROVED THEATRE ing, it might be managed by suspending the scenes on cords passing over rollers disposed in this form. Economy of In constructing the elevation of a theatre, the first consi- °^ ' deration is to economise apace, hence in the boxer,, as at IS'o. 1, fig. <-2f after allowing the seats to rise one foot in live for the purpose of clearing the view from the heads of those below, if aline be drawn to the top of the scenery from the eye of the most backward observer, the bottom of the next tier of boxes must just commence at that line, as exhibited by dots. Theatrf s too . As it is advantageous in the Metropolis to make theatres lare for the more extensive than the direct voice of an actor can fill voice to fill with ease, with ease, it becomes necessary, to cull in the aid of re- flected sound, and so to distribute the whole voice as may- be deemed most important. I have in the enclosed sketch supposed, that (in a tin aire where the extreme part of the pit is 120 feet from the centre of the stage) the direct voice is sufficient till within one fourth of the extremity of the this therefore building. Therefore, the roof is so curved, as to commence bv°lrellcctaeded its reflection at that point, as may be traced by following sound. the progress of the pulses of sound emitted by the actor at A. One half the roof, as far as C, is allowed to give the sound it receives over this portion of the pit, and the three tiers of boxes. The remaining half of the. roof is employed in throwing its sound upon the upper gallery, increasing the density of its reflection as the distance from the stage increases. Although this gallery receives the influence of half the ceiling, yet from the oblique position of it, it will not catch more than half as much sound as the other por- tion, which is fully required by the distance of the hind part of the gallery, the direct sound being there c25 times less dense than in the quarter of the pit next the stage; whereas by the reflection this disproportion will be reduced to about, ten times only, and of course it will be as distinctly heard as in the third quarter of the pif. Boxes. The ratio of sound in the three front boxes compared with that of the first quarter of the pit, is as T'~ to one; this, by the reflection of half the roof will be reduced to about 4, hence these parts will hear nearly as well as the centre of the pit. In addition to this, the back of each tier of boxes should be covered so as to give a focus of sound Kfa 0$ THE BASALTIC COUNTRY IN IRELAND- M*>* • sound either to jthc front, middle, or last benches, -A3 thought best, this shown at 1, 2, 3. The two latter, where altered from the former, by dotted coves. The fronts to the boxes should present reflecting curves, to throw their sound within the fourth region of the pit. Fig. 3 is a hind view, showing the proper curye of the roof in this position, where the only object is tp keep the diverging rays of sound parallel after reflection, and clear of the sides of the boxes. I think it would not be particularly expensive to have Cast iron beams tjie whole beam and pillar work of the theatre of cast iron ; aild pillars* and likewise to make the elliptical part capable of being completely cut off from any fire in the other part of the building, by a jointed sheet iron curtain, to close up the stage every night after performance, or in case of fire, during tfre play hours. The name of th'13 would be very attractive. To prevent the bad efTect of squeezing from sudden Doors to open alarms, no door about a theatre should open inwards, and outwards# , the outlets should be as large as possible, and some extra ones easily opened if necessary : a good reservoir of water, and an engine pr two on the spot, are precautions too ob- vious to need an observation. I have the honour to remain, Sir, Your obedient servant, GEQ. CAYLEY, II. A Letter on the Alterations, that have taken place in the Structure of Rocks, on the Surface of the Basaltic Coun- try in the Cotmties of Derry and Antrim, Addressed to Humphry Davy, Esq., Sec. li. S. by William Kichardso.n, D. D. (Concluded from p. 175. ) Inquiry into the Formation of our perpendicular Facades. T is natural, that the first great operation we proceed to Formation of inves^gate should be the formation of our magnificent fa- the cliffs. jades, u* ON THE IA8ALTIC COUNTRY IN IRELAM). C.ades. one of which is the principal subject of this me- moir. The line of coast, that bounds our basaltic area on its north side, extends about twenty-five Irish miles, in which course the precipices are nearly continuous, and more than one half of them absolutely perpendicular for a great part of their stupendous height. The operation by which they were cut off so abruptly, and left with a formidable aspect towering over our coast, is the one we inquire into. Theyoncepro. That these bold precipices once projected farther in many places is easily demonstrated ; at Beanyn Daana, and attheChimney, thecolumnar construction was obviously once carried much farther out. At the Milestone^ Portcooan, and Porlnabau, the frag- ments of dikes extend far beyond the face of the precipice. Not formed by These same facts, together with the projecting base, show, a part, or *any that these sudden abruptions were not formed by the subsid- violent convul- jng an^ sinking of one part, leaving the remainder in its place: still less by any violent revolution, or convulsion; as the stratification has not sustained the slightest shock either above or below the facade, or by the beat- The formation of our abrupt coast has been ascribed to ingofthe t^e ac^on 0f the sea beating violently against it, washing waves. ° j n > o away the lower parts, and leaving a perpendicular facade standing; as we often see on the banks of rapid and en- croaching rivers. For the eliffs A cool examination of our precipices will soon prove, that are too high, Qur facacies could not have been so formed, for we always find them in the highest part of the cliff, and receding from the water, which could be instrumental in bringing down the materials from above only by washing, and so wearing away the bases of the steepest parts ; but the elevations of these bases are utterly irreconcilable to this supposition; for in- stance, the base of Pleskin fagade is two hundred feet above the present level of the sea, that of Fairhcad three hun- dred ; now had the sea ever risen to either height, it would hare submerged a great part of Ireland, and none of the neighbouring country (whatever its level may be) bears the least resemblance to alluvial ground, nor shows any mark of having been once covered by the$ea. The ON THE BASALTIC COUNTRY IN IRELAND. 247 The next argument is still more conclusive; the boun- and occur dary of our basaltic area on its north side is for twenty-five e£* * • In n • ' miles also the confine of sea and land ; so far it is natural to ascribe its features and characteristic marks to the ac- .. tion of the powerful clement that beats against it, But when that precipitous boundary ceases to be the confine of sea and land, turns southward towards the interior, and be- comes thu line df demarcation between the basaltic and schistose country on the west, it still preserves its former character; that is, of a range or ridge of very high land, steep to the exterior, and sometimes cut down vertically into facades, like its northern part that lines the shore. Thus MagiUigqn Rock, (four miles inland) is not inferior Instances; in magnificence to any of our facades on the coast, its per- pendicular section is one hundred and seventy feet, and this continuous for a mile; the facades at Bienbraddock are nine miles farther inland, and those of Monyneeny thirteen; while the base of the lowest of these perpendicular precipi- ces is elevated 1400 feet above the sea, The same style prevails on the east side of our basaltic area, after its boundary ceases to- be the confine of sea and land ; for the limestone facades at Garron Point, (consider- ably abov« the level of the sea) exactly resemble those of JDunluce and Kcabaan at the water edge; and Cave Hill (several miles from the sea, and nearly one from the shallow estuary of Belfast,) exhibits basaltic facades at the height of one thousand feet, precisely similar, and little inferior to those of MagiUigan. The exact resemblance between our inland facades (on the These resemble Cast and west sides of our area) to those on the shore, those on *&« proves them to be all effects from the same cause, and that * our accumulated strata have in all these similar instances been cut down vertically by the same agent, and that thjs agent was not the sea. Nor has this powerful agent confined its operations to our similar appear; coast, or to the periphery of our basaltic area ; we can trace aaccs iu thein8 it over its whole surface; we find throughout its interior, basaltic coun- similar, though very diminutive abruptions, executed pre- try. cisely in the same manner, that is, strata cut across by ^ Jong vertical facade, their planes on the upper side perfectly undisturbed. 248 ON THE BASALTIC COUNTRY IN IRELAND. undisturbed, while on the lower side all the materials of which that part of the stratum was once composed are com- pletely carried off.— (See 6th fact.) We are now unavoidably led into a discussion of a ques- tion, which has at all times occupied the attention of na- turalists. Whence arise the Inequalities, with which the Surface of the Earth is so exceedingly diversified ? Whence arise I shall not attempt to encounter this question generally, theinequah- nor* to extend my inquiries beyond the limits I have pre- ties on the sur- ■ J J ' . r free of the scribed to myself; but I shall try whether the curious facts, Earth? ^ profusely exhibited over our basaltic area, throw any light upon the formation of our own inequalities, or lead us a step toward the discovery of the operations, by which such stupendous effects have been produced. Som« say from Some, to escape the difficulties in which this question is original forma- jnvo|yej^ ascribe our inequalities to original formation ; as if the world had come from the hand of the Creator with the variegated surface, which now contributes so much to its beauty. But the frequent interruptions and resumption* of the strata in our area, with the perfect resemblance of the corresponding parts, however great the interval by which they are separated, can scarcely leave a doubt, that these strata were at first continuous; of course the figure of our surface at that time must have depended on the original positions and inclinations of these strata, which, as appears by the 3d fact, are now unconnected with the superficial line, the figure of which is governed by their abruptions and removals alone. others from Naturalists have differed much in opinion as to the direc- causes within tmn jn wnich the causes acted that produced the inecmali- or on the sur- ' ^ face of the ties on the surface of our globe; some referring us to the Earth. bowels of the Earth as to the scene of action; while others assert, that the operations were performed upon the surface itself. But the slightest inspection of our facades will at once prove, that the first hypothesis cannot be correct; for obli- quity of direction must have been the result of a disturbing cause acting from below; whereas parallelism. and a steady rectilineal ON THE BASALTIC COUNTRY IN IRELAND. £4^ rectilineal course distinguish the basaltic arrangement^ of which I have been treating. We have, it is true, occasonal depressions of our strata, Sometimes where they obviously have subsided, and no doubt tVom a *ubs?deTfrom failure of support below; but in no instance that I have failure of their met with, in our area, are these attended by the slightest suPPort*- concussion ; the permanent and subsided parts, with us, still preserve their parallelism, and the continuity of their 4* material; whence it is probable this event took place pre- vious to the induration of the strata, ant} of course antece- dent to the period, to which I limit myself. |W . B u f Foil ascribes our superficial inequalities to the agita- Suffoifs type* tion of the waters while thev covered our Earth, and argues thesis- from the resemblance these inequalities bear to the waves of the sea; a resemblance I cannot trace in any country, which I have observed ; nor could any sudden and perpen- dicular abruptions ever have been produced by any agita- tion of the waters. • *> m tc%VMUij'man Professor Playfair considers rivers as having formed not piayfair's. only the beds, or channels in which they flow, but also the whole of the vallies through which they run, and in general all the inequalities of our surface; but an attentive observer, tracing the course of any of our most rapid rivers, would soon perceive, that the quantity of its depredations have been comparatively insignificant, and that they can be de- termined with precision ; the river has no doubt in several places extended itself considerably on both sides; but in the intermediate space, between the remotest boundaries it ever reached, it levels, instead of raising inequalities. The same result I apprehend would follow from the ope- Decay and de- rations of another agent, which theorists are in the habit of compobiuou. calling in to their aid, when they cannot find some certain material, which from their theory we have reason to expect; they then tell us it has been carried off, and lost in the suite of degradations and decompositions. But delay and decomposition, instead of creating inequa- But tl lities, would produce a contrary effect, and deface those ac- would wear tually existing; they would gradually abate the height of|^"^paro" our perpendicular facades, and increase the green steep at their bases by the accumulation of the crumbling and mouldering £50 ON THK IMS A I t IN IK*.!. 4 N 1>, mouldering materials from above; white the more dim tive facades, formed by the abruptions of single btrata scat- tered over the face of our are;), and funning its most char;c .■- teristie feature, would in time (as many are aln'ady) be converted into steep accliviti'.- cqvered with verdure. The effects Such are the principal causes, to which the inequalities of first to be exa- our surface have been generally ascribed. Previous to our sum ., deciding finally 'upon their insufficiency, it may be proper to enumerate a few of those inequalities, where the devia- tion of our present surface, from the form it probably had originally, is not only striking, but where also the concomi- tant circumstances afford demonstration, that some great operation has once taken place there. Thus, by marking ourselves acquainted with effects, we shall be better qualified to investigate causes; and if these effects shall appear to be beyond the powers of such natu- ral agendas we are already acquainted with, we shall be justi- fied in admitting the performance of operations, to which we have seen nothing similar; and also in admitting the for- mer existence of powers of far superior energy to any we have ever known in action. Enumeration of some remarkable Inequalities in the Surface of our basaltic Area, produced since the Consokdation of its Strata. Remarkable That we may better understand the facts I am proceedr inequalities ing to state, I shall assume (in the style of the mathemati? Se^ewi^Hd"^ c',ans Puta factum) Previous to demonstration, that the tionoi the planes of our uniform, rectilineal strata, however interrupt- stiata« ed we may now find them, were once continuous. Upon this supposition, the valley of the Mayola, between the stratified summits of Scafin and Slievegal/on, is an ex- cavation 1700 feet deep, and three miles wide, of which the whole materials have been completely carried off. To the northward of this excavation, between Seafn and Carntoglter, the continuous accumulated strata of basalt are interrupted, ami taken away quite down to the schistose substratum; while the untouched summits of the conti- guous mountains, Carntogher, Scaiin, and Momjneeny, are stratified basalt. On ON TIJF, BASALTIC COUNTRY IN IRELAND. gt5 \ On the eastern side of our area, immediately to the southr Remarkable ward of Kdip and Connor, a similar operation has been per- produced since fprraed, attended by still more extraordinary circumstances, the consolida- We here find a district near four miles in diameter, Slrata< called the Sandy Braes; over this whole space the basaltic stratification has been carried off, and the operation has reached deep into a very singular substratum? a reddish breccia, by some mineralogists called a porphyry, the mass friable, but the component angular particles of extreme hardness. n The hills, of which this little district is full, are every one perfect segments of spheres j while the loftier basaltic hills that surround it preserve their characteristic form, to wit, a gradual acclivity on one side;, with a steep abruption on the other. As we sail along- our northern shore we discover another great chasm or interruption of our strata, which also cuts deep into the substrata: for on the west side of Ballycastle pier, the bold basaltic precipices suddenly disappear, and at a lower level disclose the substratum, which appears to be *n alternation of sand-stone and coal, sometimes with bitu* ruinous schistus. A mile or two to the eastward the abrupt precipice is re- v sumed, and a basaltic stratum again occupies its summit on to Fairhead, with the same angle of inclination iti which it was disposed along our whole coast, that is a slight ascent to the north. Traces of similar operations and abruptions are to be found over our whole area, but the preceding are sufficient tp make us acquainted with the style of these interruptions of our strata ; of course it is time to proceed to the sus- pended demonstration, that our strata, so interrupted, were once continuous, notwithstanding the magnitude of the in- terval by which the corresponding parts are now separated. Proofs Jhat our noiv interrupted Strata were once conthiuous. We must now turn back to the facades of Bengore, proofs that tlw where the strata themselves, and all the circumstances at- interrupted tendiag them, are so happily displayed, as to throw great -traUwcre light ON THE BASALTIC COUNTRY IN IRELAND- once con tinu- light on 'the subject, and to lead us analogically, step j»* aus- step, to the conclusion *e seek lor. Let us examine and trace the summit of the precipice for a mile immediately eastward from the Giant's Causeway^ and wv shall ftrid a frequent interruption and resumption of the fourth, fifth, aad sixth strata, at the shortest intervals, the interruption not always reaching to the lowest of the three, which in that case remains continuous: so far simple inspection removes all doubt, that each of these strata was. once contiguous as far as the great depression to the west of JPteski*. Here indeed the interruption becomes considerable, not Jess than a mile; but when we find at Portmoon a succession of three strata with the same inclination, in the same order, of the same thickness each, and with the same strong cha- racteristic marks, that distinguished the three interrupted, at the depression ; above all, when we find the strata they rest upon continuous (at least with very trifling interrupt tions) for the same extent ; I think we can scarcely entertain a doubt, that this interval between the corresponding parts, though so much greater than any of the preceding, is, like them, but an interruption, and that these strata were once continuous from the depression to Portmoon. The same style of induction would establish the quon^ dam continuity of all the strata in the face of Bengore pro- montory, for here the strata are so distinctly marked, that we know each of them, when we find it again after any in- terruption. In the rest of our precipices and facades, the similarity of the strata deprives us of this advantage ; yet in their smaller interruptions, the eye, by tracing the rectilineal course of the strata, and so connecting the separated parts, can establish their former continuity: while in the greater in- tervals we must rest our proof on analogy alone. That we may be entitled to carry this style of induction into the interior of our basaltic area, and to apply the same reasoning to enable us to form a similar decision upon the more stupendous interruptions of our strata, which I have already enumerated, it becomes necessary to explain the geological (*N THE BASALTIC COUNTRY IN IREtANtf. £53 geological construction of our area, — the strata of which it Proofs that the is formed — the urragement — and their inclinations. strata were - An extensive limestone stratum, white as chalk, and once c*utiru»* about two hundred feet thick, seems to form the base of ous* the whole district I limit myself to : upon this accumula- tions of rectilineal and parallel basaltic strata are heaped up to most unequal heights. This great calcareous stratum seems not to be on accu- rate plane, but rather to resemble a basin, as every where af its periphery it dips to the interior ; yet the plane of its sec- tion has a slight ascent to the southward. A recollection of these circumstances will enable us to account for every ap- pearance this stratum exhibits, as it happens to be disclosed to us ; and by the converse, an attention to these appear- ances will enable us accurately to determine the position of the stratum. This stratum, from Ballycastle to Solomon's Porch, (about % twenty-five miles, ); keeps very nearly the level of the sea, often indeed sinking below the surface, but never raisim - lower edge above it; but when, at Solomons Porch, the boundary of our basaltic area begins to deflect to the south- west, and then to the south, the ascent of the stratum to the southward begins to operate, and we perceive the dotted line of its quarries gradually to rise along the face of the mountain from the shore to Mouynceny and Seafin, where it has attained the height of 1500 feet. It is true, the actual stratum has not been opened at these two great elevations, but the white rubble immediately below the basaltic facade proves incontestibly, that it is close at hand. An accumulation of basaltic strata had in this southern course, as well as on the northern shore, covered the lime- stone up to the summits of the hills or mountains. I have already stated how the ridge of mountain is sud- denly interrupted by the valley of the Mayola, from l600 to 1700 feet deep ; but if we look to the southward, in the rectilineal course of the strata (the positions of which vre have been able to ascertain with so much accuracy), we shall find near the summit of the mountain Slkvegalion a similar white limestone stratum crowned with basalt, cut- ting it in the very direction the former ought to have reached ££4f oy fHE BASALTIC COUNTRY IN IRELAND. proofs that the it, that is perhaps two hundred feet higher; the ascent of K*tetrrUwere tne strata to the southward having elevated their planes so once commit- much in a distance of four miles, the probable interval be- ous# tween the summits of these mountains. We are now to decide whether this calcareous and basal- tic fragment, on the summit of Slievegallon mountain, be the last remnant of the old arrangement we have been trac- ing, and ascertaining with so much precision, for seventeen or eighteen miles from the sea, and twenty-live miles along the coast ; but now interrupted by the valley of the Maijola, like our former more diminutive interruptions, and also like them resumed at the next elevation, in the same rectilineal course, the strata preserving the same order, and the same characteristic marks- Or whether these strata, appearing on the summit of Slievegallon, be the commencement of a new arrangement, abandoned by nature as soon as begun: which is highly improbable, for neither limestone nor basalt is to be found on the mountain, except in this solitary hum- mock. We might, by a minute attention to the inclinations and arrangements of the strata contiguous to the other interrup- tions 1 have enumerated, prove in like manner, that the ba- saltic masses crowning the summits of the surrounding hills and mountains are merely the remnants of strata once extensive and continuous, but interrupted and carried oif, as in the preceding case, by the same powerful agent. The more diminutive inequalities scattered over the whole surface of our area, and always produced by interruptions oi the strata, would still more easily admit the application of the same reasoning, from the contiguity of their abrupt- ed parts ; but the detail would be tedious ; those who wish to pursue the subject farther must come to the scene them- selves. Materials completely carried off. Materials com- A circumstance perhaps still more extraordinary is the pktely corned oomplete removal of all the materials, that once filled up the intervals between the abrupted parts of these strata. I have stated in my 9th fact, that the materials, that had for- merly composed the projecting parts of our northern facades and precipices, had totally disappeared. 0\ THE BASALTIC COUNTRY IN IRELAND. £55 The removed parts of the limestone stratum on thereat side of our area have shared the same fate : for where the 'iiiiin of mountains extending from Magiiitgan Rock to Bienbraddock is interrupted by the vallies at Stradreagh, Urumrommer, and Ballyncs&,\t is obvious that the limestone stratum was onee continuous to the high points where it shows itself on Keadyy and the mountains on each side;.' its thickness too, wherever we can try it, is very great ; yetthis stratum, which in its entire state must have spread like a Toof far above the present surface of these valSies (which are now sunk deep into the schistose substratum) has not left a particle of its debris behind, nor is a single lump of white limestone to be found, until we come to the quarries, that is, to the edge of the solid, untouched stratum. Conclusions. The conclusions that unavoidably follow, from the consi- General infer* deration of these facts, are, ences. That the hills and mountains, in the district I have been describing, were not raised up or formed as they now stand, but that they are the undisturbed remains of strata that were left behind, when stupendous operations carried away the parts that were once contiguous to them. That the inequalities of this surface were all produced by euuses acting from above, and carrying off whatever they touched, without in the least disturbing what was left be- hind. Additional Evidences, Basaltic Hammocks*. The arguments on which I have founded my opinions Additional have hitherto been alt taken from the hollows in our surface, evidence in th« and the interruptions in our strata, both which the conco- mock*. mitant circumstances have led me to consider as so many excavations; but the lofty elevations, and the abrupt pro- minencies rising suddir.gly from our surface, when minutely examined, lead u^ irresistibly to the very same conclusion. When you aud I examined together the line of our northern facades, we studiously sought for the points where * Navigators use the word hummock to express circular and elevated mount?, appearing at a distance; i -adopt the term from them. nature 256 0N TIIE BASALTIC COUNTRY IN IRELAND* Additional evi- nature had made any change in her materials or their ar- Sticnhum- rangement, hoping that at the junctions of the^e little sys- mocks. terns we should find some facts, that would throw Tigbt on the subject; but we generally failed; want of perpendicu- larity, or other local circumstances, impeding us at the most interesting points. On the present occasion she has adopted an opposite line of conduct, and in many of the steps she has taken, ob- trudes upon us demonstration of what she has done. Whoever has attended to the exertions of man, when em- ployed in altering our present surface, either by levelling heights, or by making excavations, must have observed that it is the practice of the workmen to leave small, cylindrical portions standing, for the purposes of determining the height of the old surface, and thereby ascertaining the quantity of materials removed. To these may be compared the stratified basaltic hum- mocks so profusely scattered over our area, and which seem to show how high our quondam surface once reached. The hummock of Dunmull, three miles south-east from Portrushy is very beautiful; it stands on the top of a high ridge, and is a conspicuous object from all parts of the country; it is exactly circular, its flat surface contains an acre, it is completely surrounded by a perpendicular facade about twenty-five feet high, and formed by two strata, a columnar, and an irregular prismatic resting upon it. From this elevated station, where I had the pleasure of accompanying you, I showed you at six or seven miles dis- tance to the westward, among the Derry mountains, the still loftier hummocks of Altabrian and Sconce, hemispherical in form, composed of but one stratum each, while their swelling-out bases displayed accumulations of many more: and also near the hummock of Fermaylc, resembling Dun- mull, but much larger, and also surrounded by a facade composed of two strata. i showed you also at twenty miles distance to the south- east the gigantic Slcmish, one of our basaltic hummocks, magnified (as it were) into a lofty and insulated mountain, completely stratified from its base to its flat summit. I showed you likewise from the bottom of its ridge the neat ON THE BASALTIC COUNTRY IN IRELAND^ ^57 neat but diminutive hummock culled the Rock of Clogher, Additional evi- above Bushmills. As our time was precious, you took my ^salti^hum- word for its stratification being precisely similar to that of mocks. DunmvlL **■* $ There are many other basaltic hummocks scattered over the surface of our area, all of them either stratified or por- tions of strata; two of the most remarkable are the hill of Knock Loughran, near Maghera, and a tall hummock (the name of which I forget) a mile eastward from Lisanoure. We meet still more frequently ah imperfect style of hum- mock, a semicircular facade on one side, while on the other it slopes away gradually with the dip of the strata, as if the operation had been interrupted before it was carried quite round; the most remarkable of these are Ballystrone, in Dcmji and Croaghmore, in Antrim, both visible from Dun- mull. Regular stratifications on the summits of hills and moun- tains havt; long been a stumbling block to theorists. The historian of the French Academy, for the year 1716, ob- viously ascribing the superficial inequalities of the Earth (like many others) to causes acting from below, and perceiv- ing how incompatible such assemblages of strata were to his theory, thinks it safer to doubt their existence, as they could not have been formed, he says, " unless the masses of the *' mountains were elevated in the direction of an axis per- " pendicular to the horizon : ce que 11 a pu kre que tres " rare.J> But as these stratified mounts are in our area by no means uncommon, they lay us under the necessity of sug- gesting another alternative similar to those we have already stated. Were these isolated hummocks originally formed as they now staud, (solitary and separate from each other) one by one? or are they the last remaining portions of a vast conso- lidated mass, of which the intermediate and connecting- strata have been carried off by causes, with which we Ire unacquainted ? To be able satisfactorily to resolve this alternative, it be- comes necessary, to take a careful view of the contiguous countries, and to try whether their construction,, and the ar- Vol, XXII.— April, 1809. S rangement 253 ON THE BASALTIC COUNTRY IN IRELAND. Additional oi- rangcment of their strata, will throw any light upon the ffi&L 8ub-icct- mocks. When we examine the assemblage of hummocks above Knockmull, that is, Sconce, Fermoyle, and Altabiian, we find their materials and stratification precisely similar to that of the country below them to the eastward, where the abruptions of the strata ara displayed in long stony ridges ; to the south, the abruptions on the summit of Kcady moun- tain discover the same similarity ; and to the north-west the grand facade of Magilligan Rock, three miles distant, dis- plays an accumulation of exactly the same sort of strata consolidated into an enormous mass. The hummock of Dunmull is formed of two very parti- cular strata, a columnar, and an irregular prismatic; but I showed you, a mile to the northward, at the facades and quarries of Islamore and Craigahuller, at the base of the hill, that the whole ridge, on the summit of which Dunmull is placed, was a consolidated mass, formed by alternate strata of the same'description : and that the arrangement of the whole country below, and adjacent, was precisely the same with that of the hummock of Clogher, I proved to you at the curious opening of the strata at Bushmills Bridge, and in the facades at the Gianfs Causeway. After these proofs, that so many (and I might proceed to the rest) of our detached hummocks are in their construc- tion and materials similar to, and connected with, the main consolidated masses of which our country is formed, I think it will scarcely be asserted, that these hummocks were originally formed solitary and separate as they now stand ; but rather that they were once parts of that vast whole, and left behind at their present form, upon the re- moval of the contiguous portions of their strata by some powerful agent, of whose operations and modes of acting we have hitherto obtained little knowledge. o The highest point on the facade of Cave Hill is called M'Art's Castle, and appears to be a solitary fragment of a stratum, precisely similar to those below it, and obviously once extended like them. The inegularity of the summit of Fairhead plainly shows, that iu gigantic column* once reached higher. And REMARKS ON THE IMBER AND NORTHERN DIVERS. .^g And in the facade of Magilligan, the highest of all. a few Additional evi. desultory patches of an upper stratum (no doubt once per- ^^^ "feet and continuous) are to be traced along its summit. mocks. Our mountains themselves seem to show clearly, that they were once higher ; the top of Magilligdn mountain is an ex- tensive plain, over which a wandering stratum is interrupt- ed and resumed at intervals for a great way. At the highest part of Donald's Hill, over the valley of Clenuller, we tind a hummock; also at the termination of the ridge, at its highest part over the valley of Mayola, si- milar hummocks. I have the honour to be, Sir, Your obedient, humble Servant, Clonfecle, Jan. <2, 1808. W. RICHARDSON. III. Remarks on the Habits of the Imber and Northern Divers, in answer to a Correspondent, In a Letter from Thomas Stewart Traill, M. Z>. To Mr. NICHOLSON. SIR, IN article X of your last number, a correspondent wishes Author of th* for information concerning the habits of the Colymbus Im- *?count of thc mer. The observation of the Reverend Author of an Account mistaken. of the Feroe Isles must be incorrect, when he asserts, that ** the imber lives constantly on the dry land.1* Both the colymbus immer, and c. glacialis are frequently Habits of the met with among the Orkney and Shetland isles, where I northern di- have had many opportunities of observing them swimming vers. about with great velocity, and experienced the difficulty of shooting them, from the celerity with which they dive on the flash, and the very great distance they swim underwater. The inhabitants of these islands have never seen either of Similar story of the two species of diver above noticed on the dry land : and. hs I"0!??!00 . . r _ . . - •■-. . ,* , i / ,. ' m the Orkneys to explain the incubation ot a bird which they believe never and Feroe quits the water, have had recourse to the story of its hatch- islan<1*' ing its egg under its wing, a3 well as the natives of the Fe- roe isles. As the egg has never been found in such a situa- tion by any one, it is not easy to discover the origin of such S 2 a stor £60 GALVANISM IN DEAFNESS. a story among the inhabitants of the Feroe isles, if they be- lieved that the diver lived constantly on the dry land. It seems obviously to have originated among them from a similar cause that produced it among the inhabitants of the Orkney and Shetland islands, a peaple till lately connected with those of the Feroe isles by Frequent intercourse and common language. Jaloust.0ryf*" ^he trut]l is' l bL'llev.e> tlmt the two species of colymbi here noticed live almost constantly on the water ; when they leave it, it is only for the purpose of incubation; and they then seem, from the best accounts, always to choose some se- questered spot very near to their favourite element. Indeed the position of the legs of all the divers, and the structure of their feet, show that they are totally unfit to live con- They neTer stantly, or even principally on the dry land. 1 have never I'idlv Imh se€I1 either the c. immer or c. glacialis attempt to fly; nor stay very long did I ever hear any one say, that they had observed them do under water. gQ^ \\rjien closely pursued they swim with great ease and rapidity, and dive for a much longer time than any other bird I recollect to have observed. 1 am, Dear Sir, yours very truly, Liverpool, I8O9. THO§. STEWART TRAILL. IV. Inquiry concerning the Use of Galvanism in Deafness. By a Correspondent, -I To Mr. NICHOLSON. SIR, Apphca.ion of J^T appears, that galvanism is successfully applied 111 some galvanism in f ., , .. . .... , , cases of deaf- cases ot deafness; and particularly in such as cannot be re- news, lieved by other means. I am so fully persuaded of your desire to render the Philosophical Journal subservient to objects of utility, that I presume to request you to invite your correspondents, to transmit a particular account of the mode of applying galvanism in cases of deafness. I am, Sir, Your most obedient servant, rei.im. T. V. NEW ADDITION AND MULTIPLICATION TABL£S^ %0\ V, Jin Addition Tabic, with a Multiplication Table on a new Plan. By Mr. Charles Hayter. SIR, Vec. 27, 1803. iVlY son desired me to make him an addition table; the Addition table, thought was new to me; but trying, I produced the en- dosed, and since have done the multiplication table in the Improved mil- form herein presented. Several teachers have complimented ^l0atl0n u* the plan ; because, wheti the Tables are learnt, the man- ner of setting down the sum is also perfectly taught, which is not the case with any other multiplication table. The multiplication table of 144 squares is well adapted to stand at the beginning of duodecimals ; and I have not the conceit to suppose the form I have produced will be any where preferable, but in the hands of very young be- ginners. Your opinion, Sir, of the composition will pblige Your obedient servant, CHARLES HAYTE 42, Margaret Street, portrait painter* (Javcndish Square. ANY means for facilitating the early acquirement of Addition sel knowledge must be of value to society. It is certain, that jj^^11 though all educated persons can multiply figures very well, yet there are few, except those in counting-house, who ca add with rapidity and certainty. This author's Table, if well fixed in the memory, appears to afford a remedy for the last evil. But I would observe, that the square multi- Completa i plication table has the advantage of giving products readily es * when the factor is the largest of two numbers; so that a boy thus taught can as readily say 8 times 4 is 32, as 4 times 8 is 32, which it is well known cannot at first be done by one who has learned only the half-table with braces. It would be an improvement in both tables of Mr. Hayter, if they were thus completed. W.N AV w ►J pp o »— I U 2 »— 4 5 •J H O 5 < ©* o» CM oi co CO CO CM t* 1 - 1 CO CM to © 'O ni co — CM O) 01 M CO rH CO CO m o pM tO to -*o l-H co co © o> © o» O CO o co o -* l-H o o to i-H o »o © *o l-H © co OCM CO OJC0 CM a V CO CO ©> to to •<* ©VO to 00 ©» CO CO CO CM CO "<* CO CO to o CO CO X l>. CM Tt- Is- co CM t>. t* CO o> c^to lO CO r>»co -<* CO o» oi CO CO co r-4 CO T* OJ CO to o CO COCO CO CO ui CM © l-H to co to to ""* o 01 «5 to to CM "* CM 00 "* CO o» r* ^ CO 1-4 CO CM CO CO CO Oi Ol CM T* JJ *>- X CO 0* o r«H Oi CO o CO rH tv r^ o» Ci CO CO 2 OiT* co »0 r-. CO CO 0) CO t> CO o CO Tf CM Ci ^ - X 10 CO CO * Hf Tj* CM <© to CO CO CO "t © t>» to Ol 01 i-* CO CO 0» «o ^ co t^ «0 rf 01 co to rH r* i-h 0* OJ 0» «t CO CO CO "t Tf CO to to © o-g 5 0 o i H-g es £ p* 0) 1 g 3 M a a S| a CU 8 CTJ C* h» •* CJ 00 <0 CJ Oi 00 O* O O c* ^ CI c* ©♦ $ go r-i CT> © rH i-l c* r^ «-1 CO »HJ f-» tal — ' f* -• N- N. 00 00 o* o>> o o 1-4 — * — !>. rat 00 rH —i mm f-» ^4 CN ■ ** 1-4 nrt Q O oo O 00 o o> O O o •H 8 • ei ti Oi tv ro O} 0C C* o>o .-« flj — > 1 rs-S <0 ts. 1 °° i 1 "3 r ^ 1 00 fcs. *o 00 00 «+ s B • *o l'° . CO o 0; P '*• !>. fc* c> > W a V 1 3 s esent form is to ables have done * .a o H H {* Fifi Six Se\ c CX o to tc oo I to s .2 1 "o M H 0><0 *0 *3 .*> rH 1 H «• o ~ ja 3 s undred comp ms in eRu 00 ^O <* Cii>* <0 r-i r-* — d\ o t^<© CO 00 fcs. »o Oi oo r>* !-i S ii ••* •3* a . Ci j 00 The inten the forms of a perfect Su Six and six make c 6 > nd seven make Eight j nd eight make s u 9 '5 G 1 S CJ ■ c« fl,g.J FLAX AN ORNAMENTAL PLANT, VI. On the Cultivation of (he common F/a.r, LinumUsitatissimum qfLimie, as an ornamental Plant in the Flower Garden. By Mr. John Dunbar, Gardener to Thomas Fairfax, Esq.* Flax cultivated J[ JJE Horticultural Society will perhaps honour with as an ornamen- . . . . . . . * _ , . . . , . . tal flower their attention a short paper, the object or which is to bring into cultivation the common Jlax, as an ornament of the flower garden, not merely as such, but with a view to the profit it will afford, at least to the servant, if not to the master; and the interest of the former can seldom be pro- moted in an honest way, without some benefit accruing to •would add to the latter. This plant, when so cultivated, like wax and the nation. ° noney> forms part of the natural riches of a country, and if it could supplant the cumbersome yellow lupine in our flower borders, the annual revenue arising from it would amount to several thousand pounds. Five persons If gardening were in its infant state among us, a com- luien fromone P^ete treatise on the culture of this plant might foe neces- gardeninthis sary; but as this .is not the case, only what is especially ay* material wjill be noticed, with some directions how to prepare the plant after it is gathered. They are the result of se- veral; years experience, by which a family consisting of •five persons has been supplied with all the linen they re- quired. A loamy soil The soil of every flower garden is always rich enough to I"**' produce good Jlax ; but if it is loamy rather than sandy, the quantity will be nearly double : even in the fields, which can never be cultivated with the nicety of a gentle- man's garden, I have observed the greatest crops in a loamy soil, and that they yielded an article superior in qua- lity as well as quantity : for as the durability of the fibre depends in some measure upon its size, there can be no doubt that tall and vigorous plants are preferable to small ones. Modeofdis- There are various ways of disposing this plant so as to ♦rnament.U ^e exceedingly ornamental, but none more so than scatter- * Trans, of the Horticultural Soc. p. 71. .FLAX AN ORNAMENTAL PLANT. %&5 iiig it in random parcels, or little clumps of from 10 to 20 plants, towards the back of the flower borders, and in the front of the shrubbery : for, without the summer proves un- commonly dry, it will attain to the height of three or four feet. If a temporary edging, or summer screen is wanting for any particular bed, it may be also employed for this purpose. The seeds of good flax are short, plump, thick, very oil}', Cuitivat;ont and of a bright brown colour. The best season for sowing them, in most gardens, is February, or the beginning of March, when the general crop of hardy annuals are put in; but if the ground be sandy, and naturally dry, they should be sown in October or November, No more atten* tion than what is necessary for the other flowers in the gai> den, which is keeping down all weeds while in the seed leaf with a hoe, will be requisite for this. As soon as the seed Gathering. begins to ripen, and the plants turn yellow, pull the whole up by the roots, and lay it in bundles exposed to the full sun, if the weather is fine, to dry completely. Then pull the heads ofT, and shake out the seeds. Immediately after, Maceration. it must be laid to macerate in a ditch, or pond of water, and kept under by a long piece of timber floating upon it. From five to ten days is the time necessary for its immer- sion, and after the fifth, it must be examined daily, taking especial care that it does not lie too long. As soon as ever you find the fibres are sufficiently macerated to separate from one another kindly, spread it out to dry upon a new mown meadow. When dry it must be again collected into Preparation, bundles, and either sent to the flax dresser, or prepared for spinning at home by the gardener's wife. In many districts, this operation is well understood, and if carefully per- formed, homespun linen from such flax will last twice the time of most of the Irish linen that is now to be purchased in our shops. I believe it is a great errour to pull the flax so green as Cautions. is commonly practised, and a still greater to soak it in wa- ter, before it is previously dried: for the fibres require twice the time to macerate sufficiently for separation in the dressing; a process by which they are considerably weak- ened. VII* 266 ANALYSIS OF A MINERAL WATEJU VII. Analysis of a Mineral Water near Dudley, in Worcester- shire. By Mr. W. Wlldon. Mineral water jr\BOUT two miles to the south of the town of Dudley, Hear Dudley. up(m '^ j^ Qf the Right Hon jj0rd Dudley and Ward> is a spring of mineral water, that lias been famous, in the surrounding country, from time immemorial, in various scrofulous and cutaneous diseases. It is said to have been used with great success in what are called obstructions of t}ie abdominal viscera, and in various cutaneous diseases; but in all cases of scrofula it has been considered as an aU most infallible remedy. The high character that it has obtained, and the great success that is said to attend the use of it, in the diseases before mentioned, has induced an opinion in the neighbour- hood, that it deserves to be more extensively known. In a disease that under one form or other is so very gene- ral throughout Britain, it is very probable, that this mine- ral water may prove a valuable and useful remedy, and de- serving of a more general attention than hitherto it has met tvith. Like most other mineral waters it would be most advisa- ble to administer it on the spot; but where circumstances render this inconvenient, jt may be sent for and used at home. I am not informed that any body, living on the spot, un- dertakes to answer orders for it; but if any physician or surgeon should be inclined to recommend it, or if any pa- tient, who may wish to try it, should be at a loss how to obtain it, on a personal application, or by letter, post paid, I shall be ready to give the address of a person, who I doubt not will send it at a moderate expense. G' : cipitate. oxide of bis- 14. a. Oxide of bismuth mixed with the fresh water in- , : . the proportion of 4 grains to 4 oz. was very slightly dark- ened. b. With the boiled water no change of colour was pro- duced. acetate of lead: 1.5. a. Acetate of lead threw down from the fresh water a dense white precipitate. When the precipitate had wholly subsided, the surface of it was of a pale ochre or fawn co- lour, apparently produced by the oxide of iron only. h. With the mineral water, after being exposed to the atmosphere for a few hours, and decanted, the precipitate was a pure white, niuateof lead: \(y. Nitrate of lead threw down a dense precipitate of a pure white colour, nitric acid: 17. Nitric acid produced no change in the fresh water, nitrate of sil- 18. Nitrate of silver produced a dense white precipitate, which was kept for several days in a dark room, without un- dergoing the least change of its colour, acetite of sil- 19. a. A few drops of acetite of silver threw down a pre- cipitate of a rather dull white colour. It was kept in a dark room for 24 hours, when it appeared somewhat dark- ened. b. The boiled water treated in the same manner did not darken the acetite of silver, muriate of 20. a. Muriate of quicksilver, added to the fresh water, totrcurji produced no immediate change. After a few minutes the water became slightly opaque, and a slight precipitate at length appeared. It scarcely exceeded the quantity of ox- ide of iron which the water contained, but the colour was of a redder ANALYSIS OF A MINERAL WATER. 2^| u redder tint than the ochrey powder which the water let fall spontaneously. b. The same salt added to some of the mineral water which had been exposed to the atmosphere for some days', and decanted, produced no change in it. 21. Oxalate of ammonia instantly produced a copious oxalate of am- i •, • -. . monia : white precipitate. 22. Oxalic acid produced the same. oxalic acid : 23. A solution of pure ammonia threw down a precipi- pureammonia: tate. 24. Equal parts of the mineral w^ter and of fresh made lime water: lime water were mixed together, and the precipitate that was thrown down was separated and washed. It was dis- solved in muriatic acid, precipitated by subcarbonate of soda, washed, and dried in a low heat. Distilled vinegar dissolved a part of it. A solution of pure potash dissolved the greater part of the remainder, leaving a brown powder. 25. Acetate of barytes produced no precipitate in the fil- acetate of ba- tered water. rvtes : 2(3. Muriate of barytes produced no precipitate in 24 muriate of ba- hours. rytes: When the saline contents of the water were concentrated by evaporation to one fourth, a slight precipitate formed. 27. Muriate of strontian produced no precipitate in the muriate of water, either when fresh, or when concentrated as in 26. strontian: 28. Phosphate of soda produced a copious precipitate, phosphate of 29. Carbonate of ammonia produced a white cloud. **~: ... , \. , t , , carbonate of 30. A crystal ot carbonate ot potash did the same. ammonia. 31. a. In the fresh water succinate of ammonia produced carl)onate of ,,/. i . . potash; a reddish brown precipitate. succinate of b. In the boiled water a few drops of succinate of ammo- amill<>nia: nia produced no change. 32. a. Prussiate of potash and iron produced a deep blue and pmssiate precipitate in the fresh water. 01 IJOlasn- b, In the boiled water this triple salt produced no change. 33. A portion of the fresh water was boiled in a glass re- Gas expelled tort, the curved arm of which was placed under an in- y 0l ing verted jar filled with quicksilver. The gas which was thus and tested with collected was tried with nitric aaid, the acid absorbed a part nuric > of it. 34. A £72 ANALYSIS OF A MINERAL WATER. superaccUtc of 34. A portion of gas produced as in 33, was exposed to lead; the action of a solution of superacetate of lead, by which part of it was absorbed. & lime water. 35. Another portion of this gas, and also the residua of the experiments 33 and 34 were severally exposed to the action of 'lihje water. A corresponding proportion from each of the gasses was absorbed. Precipitate 36. The precipitate obtained by boiling a quantity of the from boiling ^sh mineral water to about one half was washed, dried, treated with ' ' muriatic acid, and treated with dilute muriatic acid. A part of it only was dissolved. 37. A solution of pure ammonia threw down a white pre- cipitate from the muriatic solution in 36. 38. Oxalate of ammonia occasioned a precipitate in the same solution. The residuum 30,. The powder which resisted the action of the muriatic examine . acjj m ^q w^g ];0j]e^ ;n subcarbonate of soda, and then in a solution of pure potash. A part of it was dissolved by each. 40. The powder left undissolved by the last operation was boiled in muriatic acid. What remained was melted in a large proportion of pure potash. Silex was precipitated on the addition of distilled water. Thewatereva- 41. A quantity of the fresh water was evaporated ]to dry- po rated to dry- Ress. The dry mass was treated with successive portions of alcohol, the specific gravity of which was 815°. The resi- duum, which resisted the action of the alcohol, was dis- solved in water, filtered, and slowly evaporated. The cry- stalline substance thu» successively separated, was pure common salt. Contentsof the From these experiments it appears, that this mineral wa- iter, ter contains a small proportion of sulphuretted hidrogeh, the same of free or rather supercornbined. carbonic acid, carbonate of iron, carbonate's of lime, of magnesia, and of ar^il, probably carbonate of manganese also, a minute pro- portion of sulphate of time, with muriates of soda, lime, magnesia* and of argil, silica, with azote, or atmospheric air. Their propor- ' To obtain an approximation to their 'respective proportions, tions tocamin- tke following additional' experiments were made. ed# I 42. Grains Analysis of a mineral -vvatrr. 273 42. Grains by weight 22045 = 85*973 cubic inches nearly Air expelled., .of the fresh mineral water were poured into a flask, and se- curely luted to a tube terminating under a graduated jar filled with quicksilver. The quantity of atmospheric air that was contained above the water in the fiask and in the tube was ascertained to be 9*5 cubic inches. The thermo- meter was at 47# of Fahrenheit, and the barometer 29*7- The water was boiled for about half an hour. When the apparatus was cold, the whole of the air in the flask and tube was transferred into the graduated jar. When reduced to the same temperature and barometrical pressure as before the operation of boiling, it measured ltrl cubic inches. 43. The gas thus collected was washed in a solution of Tested with superacetate of lead, until no farther absorption took place, ieJaPde[acetale of The quantity absorbed was 1*95 cubic inches. 44. The gas was then exposed to the action of fresh made lime wat« : lime water, until it underwent no farther diminution of bulk. The quantity absorbed by the lime water was 2*1 cubic inches. 45. The residual gas amounting to 12*05 was next treated and sulphuret with a solution of sulphuret of lime, that had been satu- of hme- rated with azote. The quantity of oxigen absorbed was Iff cubic inches. The 9*5 cubic inches of atmospheric air contained in the apparatus consisted of 7*5 4- cubic inches of azote, and 2 — . cubic inches nearly of oxigen. The whole of the oxi- gen indicated in 45 was contained therefore in the atmo- spheric air. The small deficiency of oxigen appears to have been produced by that quantity having combined with the black oxide of iron, which during the experiment fell down in the form of red oxide. 2*65 cubic inches of azote therefore were given out by the quantity before stated of the mineral water. 46. 88180 grains by weight zz to 343*9 cubic inches of The water eya* the fresh mineral water were boiled for an hour or more and Porated* filtered. They were then evaporated to about 30 cubic inches, when the muriate of soda began to crystallize. The Muriate of water was then filtered again, and the small quantity 0f foda crystal" precipitate that was then obtained, and which from a pre- Vol. XXII— April, 1309. T vioui 874 ANALYSIS OF A MINERAL WATER. Precipitates treated with muriatic acid, vious examination was known not to contain any sulphate of lime, was added to the former. 47. The precipitates obtained from the mineral water by 46 were treated with strong muriatic acid, and boiled in it, and caustic il- wmcn did not completely dissolve them. The undissolved kali. powder was washed and boiled for some time in a silver cru- cible, with a strong solution of pure potash. The solution was diluted, the powder separated, and again treated with muriatic acid, washed, and dried in a red heat. This pow- der weighed gr. 2*6. The solution 48. The washings were all added to the solution formed in thT^ptate 47, anfl the whole PreciPitated b)T subcarbonate of soda. examined. The supernatant solution was neutralized and the precipi- tate washed. It was redissolved in muriatic acid. The muriatic solution was neutralized, diluted, and treated with prussiate of potash and iron. The precipitate thus formed was calcined to destroy the prussic acid; nitric acid was ab- stracted from it two or three times; and then it was dissolv- ed in muriatic acid. The solution was high coloured, it was diluted with water, and precipitated by carbonate of potash.. The precipitate was separated by filtration, washed and Subcarfecnate dried. The subcarbonate of iron thus obtained weighed gr. 5.3. 49* The liquor left after filtering off the subcarbonate of iron in the last operation, was boiled for three quarters of an hour or more, a light coloured precipitate after some time began to separate, which soon became darker coloured. This powder, which I conclude to be carbonate of manga- nese, when washed and dried weighed gr. 0*7 5. 50, The muriatic solution that was filtered off from the prussiate in 48 was accurately neutralized. Oxalate of am- monia was then dropped in gradually, as loug as a precipi- tate formed. The oxalate of lime, when washed and dried, weighed gr. 3*1 zz gr. 1*5 of pure- lime, or gr. 3*1 of carbo- nate of lime. 51. The solution left in fifty was then treated with pure potash. The precipitate was separated, washed, redissolved in muriatic acid, and again precipitated by subcarbonate of soda, washed, and dried in a heat of near 20f)°* It weighed 52. This of iron. Carbonate of manganese. Carbonate of lime. ANALYSIS OF A MltfKRAT/ WATE& <27£ 52. This precipitate was treated with distilled vinegar, •until the vinegar no farther acted upon it. The residuum, when washed and dried, weighed gr. 3*2. Consequently gr. Ca-bonate of 16*55 of carbonate of magnesia were dissolved by the vine- a n *5* of the subcarbonate of black oxide) Of subcarbonate of manganese • • *75 Of silica 3' Hence one gallon, or 231 cubic inches of Proportions in the water, contained Cubic Inches. » gallon. Of sulphuretted hidrogen ••.... 5*24 carbonic acid * • • • 5*64 azote 7*1 Grains. Of muriate of lime 323*93 magnesia 96*35 alumine 38*5 soda 528*63 Of sulphate of lime • 0*71 carbonate of lime 2*1 of magnesia 11*12 Of subcarbonate of alumine ••«• 2*15 of black oxide of iron • 3*36 of manganese • • *475 Of silica • . . • '2 I have 27# ANALYSTS OF A MINERAL WATER. At different I In ve before observed, that this mineral water has been water diften in ^0Ul1^ to possess different Specific gravities at different times, gravity, consequently to contain at different times different quanti- ties of ingredients, portions o/uT ^ne sPecimen °f *ats tine, con- taining one sixth of its weight of copper and silver. I shall now proceed to the mines of gold alloyed with dif- ferent metals, by which its presence is concealed. 1. Gold in the sulphuret of lead of Pontraut, Gold instil- Pontraut is a part of the chain of granitic mountains ** c known by the name bf:Petites Rousiesi above Gz and Vau- jani in Oifans. This vein is near the glaciers; it is more than two hours journey from the villages -abovementioned, and in a country so cold, that it is inhabitable only four months of the year at most. The ore of Pontraut yields to the essay 58 per ceut of lead: and this lead contains 12*2-286 gr. of silver, and 1*442 of gold, in 5Q000. 2. Cold in the Sulphuret of lead ofMottard. another: Mollard is a village of the commune of Allemont, situate on the right bank of the river Olle. The mine was opened by Mr. Schreiber in 1785 for the smelting works of Alle- mont. This ore yields 60 per cent of lead : and 50000 gr, of the lead contain 6i"143 of silver, and 1*272 of gold. 3. Gold in the sulphuret of antimony of Auris in Oisans. in tutyhumt of The. ore is a mixture of lead, zinc, copper, antimony, sil- antimony : ^eYj and gold, united and intimately mixed. It is frequently coloured by green carbonate of copper. It yields 50 per cent of antimony: and J 0000 gr. of this antimony GOLD MINEi IN FRANC*. £88 antimony are said tp contain 950 of silver, and. 4^)3 of -old. 4. Gold in the yellow copper pyrites of la Cochette. This mine is in the narrow passage of la Cochette, which m copper py- forms a communication between Vaujimi in' Oisans' aricf r Saint ^oilin in Mavrienne. The height of the mine, and its difficulty of access, will never allow it to be worked with advantage. It Appears, that it was attempted formerly, arid a tradition of the fact is preserved ; but,*as is* too com- mon! j the base, the narrative has a great deal of the mar- vellous mixed with it. The pre of la Cochette yields 35 parts of refined copper, and *0023fj or' gold, from 100 of black copper. 5. Gold of Theys in a pyritous copper. . This mine, is in la Combe-de-Merle, below the. lake of another: Seche-Dent, ou the western slope of the mountain of Theys, below some mines of iron spar, and iti a forest of pines. It consists of nodules of auriferous copper pyrites disseminated irregularly in a vein of iron spar. The ore has never been accurately analysed. Yves Mi- chael du Serre, in a remonstrance to the Duke of Orleans published in l6ol, says, " it is so pure and clean, that four parts yield three of the finest gold, and it is as plentiful as 6. Gold of Alley ard in an argentiferous gray copper ore. This ore is frequently in a state of decomposition, and in trgentifer- eoloured by green and blue carbonate of copper. It is ous gray C0V~ found in nodules in a vein of iron spar, at Buisson near Al- leyard. A hundred parts of the ore furnish 60 of black copper, which yield 38 of refined copper, 4 of silver, and '003159 of gold. There is reason to suppose, that this is the mine of which Hellat speaks in his Etat des mines du Royaume, when he says, that Mr. de JBaral, proprietor of the iron mines of Aflevard, had found a fine gold mine in that district. 7. jGM £84 NECTARINES AND PEACHES ON THE SAME BRANCH. 7. Gold in the yellow copper pyrites of Ckalanches. This mine is situate above the confluence of the Ro- rites. manehe and the water of Olle, in the commune of Alle- mont. It is celebrated in the annais of French mineralogy for the richness of its veins of silver*. We do not know the proportions of the principles of this ore, which was analyzed by Schreiber, who found gold in it. IX. A short Account of Nectarines and Peaches naturally 'pro- duced on the same Branch, By R. A. Salisbury, £sql F.R.S.$c.f Nectarines ar.d JL HOUGH it has Tpng been known, that nectarines and peaches some- peacf,es are sometimes naturally produced, not only upon the times produced r 11 1 1 -r 1 on the same same tree, but upon one and the same branch, I do not find branch. ^e fac^ recorded by any author ; and having last year met with two instances, I presume to offer a short history of this anomaly to the Horticultural Society : whether the remarks it has suggested are right or wrong, I leave to be determined by more able physiologists. Earliest notice The first instance, o^' which I believe any tradition has of this. been handed down, will be found in a letter of the late Peter Collinson Esq. to Linne, which was read at the last meeting of the Linnean Society. He there, after giving an account of a supposed adulterous intercourse between two apple trees, standing near each other, one of which in conse- Smooth and quence bore both smooth and rough fruits, mentions a peach rough apples, tree, that produced peaches and nectarines. Another in- The secon(* instance occurred in Yorkshire, at Londesbo- stance. rough, then the residence of the Earl of Burlington ; it made so much noise at the time, which was previous to the death of that famous gardener, Thomas Knowlton, as to be visited «i • See our Journal, p. 124 of the present vol. f Trans, of the Horticultural Society, p. 103. by NECTARINES AND PEACHES OX TUB SAME BRANCH. 2&5 ' by the lute Dr. Richardson, and many other horticulturists of that extensive county. The third instance is commemorated by a painting of the ^d. celebrated Ehret, now in the possession of Messrs. Lee and Kennedy: being accompanied with a dissection of the two fruits, which are the alberge jaune, sometimes called the orange peach, it is very satisfactory. The fourth instance was noticed more lately in the garden 4th. of William Gilpin, Esq., East Sheen; of this likewise a paint- ing, but without dissections, has been made by Mr. Hooker, nor can I from it ascertain the variety. The fifth instance was discovered early in June last, on 5th. the wall of Sir John Arundel at Huntingdon : having never seen one, I went there immediately, and after detaching the branch carefully from the wall, soon satisfied myself that no bud had been inserted: there was however only a single nec- tarine upon the tree, which the gardener said was the belle chevreuse, and a pretty accurate sketch of the branch is an- nexed *. The sixth instance was in Mr. Wilmot's garden at Isle- $th. worthy which I also saw in August last, and learnt that his Tree usuaur tree, which is the royal George, seldom fails to produce producing fruits with both smooth and downy coats, or in fact peaches ° ' and nectarines: two only of the latter then remained, and had been much damaged by snails. I forbear to recite any others, these being more than sum- instance of th< cient to establish the truth; but my inquiries fori nuately two fruits terminated with the singular example now before you, of both fruits joined in one. I have to thauk Dr. Batty for it, who accidentally observed it among a number of peaches, sent to him by James Wyatt, Esq., from the neighbour- hood of Hounslow, during our vacation; and as it was already beginning to decay, this only method of preserving it for your inspection was not neglected. * On this branch, the bearing wood of which is about a foot in length, there are two peaches, eight inches distant from each other, and between, them is a nectarine. I did not think it necessary, to hare it reengraved. A figure is likewise given of the fruit next mentioned, one part smooth, the o the: downy. Most «2$$ SECTAItfNES AND TEACHESO^ fllE SAME *RANCH. Not as sup- Most of tlie gardeners, with whom I have conversed re* J^edo^lg to specting these anomalies, attribute them to the pollen of brought from neighbouring nectarine trees brought by bees : but, as the nectarmes by young fruit is smooth or downy long before it is impregnated, this cannot be the cause ; and in my humble opinion, no change of this sort is produced subsequently. Not that I have a shadow of doubt of the important consequences whicil ensue when the stigma of one plant imbibes potten belonging to another; bat these are only manifested in the succeeding generation. The great Linne, in the Plantce HybridcB and Generatio Ambigeria of his Amsznitates Aca- demicae, first promulgated a doctrine, which I firmly believe, that varieties, species, and even genera, have been created in this manner; and without the fullest comprehension ©fit no gardener can hope to be successful in raising new vege- tables, free from the faults, or endowed with the perfections t- * *u* ne wishes. The pith of Linne's theory is, that the new ve- Linneus's the- _ r v. ory of the pro- getable will resemble its father, or that from which the pollen ducuonof new came m stem an(j ]eaves ; but its mother, or that upon which kinds of plants. \ . . . , '. , / v. the stigma is situate, in flowers and fruit; this idea, which somewhat less restricted has been confirmed by actual ex- periments, should never be forgotten. Of the necessity of a sexual intercourse, every one who has raised a cucumber or melon is well convinced, and as far as the annual production . of these or other fruits is concerned, I have nothing to hint in addition to modern practice, except that the pollen of Pollen may be all vegetables might probably be preserved from one year* preserved. to auothev; in early forcing, it would be found very useful, and should be kept in papers as dry as possible, not apply- ing it till the stigma is moistened with its own natural exu* dation. In those countries, where dates are the principal food of the inhabitants, a famine would sometimes be the consequence of neglecting this precaution; for the male trees do not flower every year, and it is well authenticated, that pollen of this palm performed its office successfully, after being sent many miles by the post to Berlin. Other vege:a- Other vegetables sport in their pubescence as remarkably ties vary in as this, but being of less importance, are not attended to, cence.PU **~ Two years ago I observed a wall-flower-leaucd stock with both smooth and downy leaves, in Messrs. Whitley and Braioe'a use of iro:> foii ruuNiTuaK. 2g7 Brame*« nursery. The common ling, of which our besoms lire made, varies in the same way ; and the teucrium hetcr- ophyllum takes its name from this very circumstance. I conclude therefore, that all these variations proceed from ution un- laws in vegetation, of which we are yet ignorant, but which known to ns. are immediately connected with the transudation of the sap through the cuticle, and it is possible, that this may even affect the flavour of two fruits upon the same branch. .& - ■ , L__^U- X. On the Sufjstitution of Iron for Mahogany and other expen- sive kinds of Wood in Articles of Furniture, and for other Purposes. By Mr. B. Cook. To Mr. NICHOLSON. SIR, .S you have favoured me with inserting in your valu- able Journal my former imperfect communications, I have taken the liberty, to lay before you my idea on another sub- ject; and I leave it to you to judge, whether the idea is worth communicating to the world. We import at a great expense mahogany and other Mahogany and costly woods for the manufacturing of the very beautiful fur- porfedTat *m" niture in use among the higher and middling ranks of s^-at expense, society. The great advance of this article is felt by every one, who finds it necessary to purchase things made of ma- hogany. If it were possible to find a substitute for a por- tion of this article, were it only the half, t)ie post3 or piuars, as well as the frame itself, Admits of might be cast hollow, beautifully wreathed up the posts much elegance wjtjj flower, festoons, or clusters of fruit, or embossed with numberless fanciful ornaments, which the workman might touch up with his graver and chissel, to clear the foliage, &c. from the sand, and to make the flowers sharp and neat be- fore they go to the finisher. The painter might colour them so as to heve a more elegant and more handsome appearance than it is possible to give to carved wood : and besides they might be cast so light, and in such chaste symetry, as can- not be accomplished in wood. This would give employ- ment to many of our manufacturers, as every Japan ner could USE OF IRON FOR FURNITURE. 28$ could employ his hands in painting and polishing them; there would be ample scope for ingenuity in the cornices, and in the ornamenting and finishing them ; and I think they might be sold at a considerably less price, thun the Not expen- earved mahogany ones are now made at. £ 9ive« Also chests of drawers, bookcases, and bureaus, might all For chests of be made in sheet iron. The frames and mouldings might ^XaseT be rolled in rollers with grooves, with all kinds of patterns indented or engraved in the rollers, such as foliage, plain, fluted, or beaded stripes, or any ornamental work. The mouldings would thus be made rapidly in the extreme. The pannels might be cut out to lit the article, the fancy of the workman had made, in sheet iron. The mouldings, framing, and pannels, might then be beautifully japanned, painted, and polished, either to imitate mahogany; or with red, black, or any kind of coloured grounds; the pannels painted with landscapes, flowers, fruits, animals, or any de- vice fancy might dictate; the mouldings might be made in all kinds of Gothic or other shapes and forms, and the pan- nels fitted to them, and the whole piece of furniture screwed together when completely finished. The drawers might be made with light iron framing; filled up with wire work, which would make them very light; and afterward lined with silk, cloth, paper, or any substance most convenient. This would diminish the consumption of the cheaper wood, used for the drawers, 8zc. I do not think a piece of furniture finished in this man- Such furniture ner would be any heavier than oue made with wood. For notheaVier i. i » lii /. ^ • thun wood. the sheet iron tor the pannels need only be ot sufficient thickness, to stand to its form without bending, and the framing of proper strength to hold firmly together. Furni- ture made in this manner would certainly be more beauti-, i /. -i e a l i. .i More beauti- ful, and if an accident ot lire were to happen, the pro- ful,andasecu» perty contained in it would be saved. The article would ri'>" «gainst only want fresh japanning and painting again, if the flame had destroyed its beauty. Large pieces of furniture, when required to be removed, conveni©nt fot might easily be taken to pieces, as all parts would be screw- removal, ed together and put up again at a trifling expense, without the least injury : while at present a large, handsome, and Vol. XXII.— April, I8O9. U valuable 2£0 USE OF IRON FOR FURNITURE valuable piece of furniture, in removal, either by the care- lessness of the people employed, or its unmanageable size, is almost sure to be very much injured. Other advan- Indeed there is great scope here for ingenuity and im- ages\ pro^ement; it would give employ to vast numbers of men ; it would consume our own produce, that is iron ; we should get an article that would endure for ages ; and we should in part be independent of any other country, for the material that forms a beautiful and useful ornament in our houses. Particularly for 'Consider the advantage a scarce and valuable library*, libraries. . . fitted up with light iron shelves and doors, would have in case of fire. The iron pannels, as well as the doors, would always tit tight, and never warp, as wood does; and if en- veloped in flame, being almost if not quite air tight, it would be next to impossible, that the books or valuable manu- scripts should be burnt, or so destroyed, let the lire be ever so intense, as to be lost. They might be blackened, and in part reduced to a state almost like that of the papiri at Her- culaneum, were the fire to continue a great length of time without interruption ; but they would not be entirely lost ; and labour and patience might restore them to the world. Those valuable articles of antiquity, or indeed all valuable documents, that in their wooden cases are ever in danger n£ being lost to the world by fire, would be secure if preserved in iron. Modern publications, indeed, can always be re- stored to the sufferer, at a price ; but to save those, that would be for ever lost to society, those that no money could purchase, no power on Earth could restore, is surely an ob- ject ardently to be desired. Doors. Doors for halls, doors of all kinds, with light iron frames, and neatly pannclk'd, would be neither heavier, nor dearer, I thinl:, than those now in u^e; and if they should be a little heavier, custom would soon reconcile us to the use of them. In case of fire, an iron door might perhaps save the contents of a valuable room; instead of serving, as doors now do, to conduct the devouring element to the next apartment. Drawing-room doors, especially, and various other articles, if expense were no object, might be made of more beautiful and delicate workmanship, than it is possible to produce in wood. For instance, all kinds of Gothic scrolls, might be made RULES FOR ASCERTAINING SQUARE NUMBERS. gQ 2 made of iron, light and elegant, and every plate or pannet, that fitted them, might be pointed with any kind oi device imagination and taste might devise, beautiful as the ancient painted windows of cathedrals, and they would endure for centuries. But I need not farther expatiate on this subject. If frflhi Conclusion; the above hints, anyone would enter upon it with that kind of spirit the thing' requires, select ingenious mechanics, and study to introduce it with lightness, elegance, and taste; wfien it is considered, that the price in general would be less 4 than mahogany, that it would be handsomer and more du- rable, that it is the production of our Own nation, and that it would give employment io vast numbers of our own countrymen ; I flatter myself with the idea, that in a great many instances', it would be adopted; I am, Sir, Birmingham* Your obedient humble servant, Caroline Street, March 16, 1809. B. COOK. ±1. Oh ascertaining Square Numbers and Biquadratics by Inspect tion. By W. Saint, Esq; To Mr. NICHOLSON. SIR, Woolwich * March \5th, i&0£. JLjLaVING frequently experienced, in the solution of To ascertain by questions involving a quadratic equation, and more particu- inspection 1»m1 v in such as relate to the diophantine algebra, a consi- wllel;iCr :i J r a ' number be a durable degree ©f inconvenience and trouble from not being pe feet square able to ascertain whether a number be a perfect square Or woulJ °'u'n not, without the tedious operation of extracting its rout; trouble. I have thought, that the following rules or propositions, which I have accompanied with their demonstrations, might prove useful to many of your readers, by enabling them, on inspection, to ascertain a great vauety of forms of numbers, U 4 which 0<}<2 RULES FOR ASCERTAINING SQUARE NUMBERS. which can never be squares, and thus at least preventing them the trouble of perhaps many useless extractions. Should you, Sir, deem these propositions of sufficient im- portance to occupy a place in your useful nliseellany, your insertion of them will oblige, Sir, your very humble servant, W. SAINT. yVqiftrcnum- Proposition 1. — A square number cannot terminate with l# cannot ter- - - >' _ minatewithS, *> J> n op b# S, 7, or 8: Demonstration. — The terminating figure of every product arises from the multiplication of the terminating figures of its factors. The terminating figure therefore of every square number must arise from the product of 0X0, IX 1, 2X2, 3X3, 4X4, 5X5, 6xt>, 7X7, 8X8, 9X9; and these products it is evident, can only end with 0, 1, 4, 9, 6, and 5, and never therefore with 2, 3, 7, or 8. Q. E. D. or with an odd Prop. 2. A square number cannot terminate with an odd Demonstration, Since every square number ending with 0 must have its root ending with 0, such a root must be of the form 10 my and the square number itself therefore of the form 100 m* \ where it is evident, that whatever value be given to m, the product 100 X ma must terminate with two ciphers! It is also obvious, that it cannot end with more than two, unless ma end with an 0; which again can only be when m is of the form 10 m, or rri1 of the form 100 w~, and therefore 100 X tn% of the form 10000 X «4, which must end in at least four ciphers; and so on as far as we please. Q. E. D. If it fonrvnate Prop. 3. If a square number terminate with 4, the last v.i'li i, thelavt fjoUre but one will be an even number. but one °_ . .. „ ., , , mtit be even. Demonstration, 1 or swell a square number must have i+s root ending in 2, or 8 ; this root will therefore be of the . fgrm 10 ?n 4- 2, and its square of the form 100 m1 +- 40 m \ 4 ; where, whatever value be given to m, the sum or dif- ference of the first and second terms will give an even num- ber of tens, and an even number of tens plus 4 must have the last figure but one an eveti number. ' Prop, RULES FOR ASCERTAINING SQUARE NUMBERS. $$% Prop. 4. If a square number terminate with 5 it will If with 5 the . , * preceding fi- . terminate with 25. guie must be Demonstration. For such a square number would have a 2. its root ending in 5, that is, would have its root of the form 10 m + 5, and consequently the square number itself would be of the form 100 m* -f- 100 m -f 25; where it is evident, that, whatever value be given to iw, the sum of the two first terms will end with two ciphers, and therefore that the whole sum will terminate with 25. Q. E. D. Prop. 5. If a square number terminate in an odd num- If with an oaA ber. the last figure but one will be an even number, but jf number, the O last figure but it terminate in any even number, except 4, the last figure one will be but one will be an odd number. V^lXZSfr it will be odd. Demonstration. By prop. 1 , if a square number end in an odd number, it must be in 1, 5, or 9 ; and by the last prop, when it ends in 5, the last figure but one will always be 2, which is an even number; and when it ends in 1, or 9, its root must end in 1 or 3, that is, must be of the form 10 m -h 1, or 10 m + 3 ; and therefore, the square number itself of the form 100 m* +20m+l, or 100 m* -f 60 m + 9; where, whatever be the value of m, it is evident, that ' the sum of the two first terms in either expression will give an even number of tens; and an even number of tens plus 1 or 9 will have the last figure but one an even number. Again, if a square number end in an even number except 4, by prop. 1 it can only be in 6, and its root must end in 4 or 6; that is, it must be of the form 10 m + 4, and conse- quently the square number itself of the form 100 m* + 80 m -f- l(j; where it is evident, that, whatever be the value of m, the sum or difference of the two first terms will always give an even number of tens, and an even number of tens plus 16 must have the last figure but one an odd number. Q. E. D. Corollary. Hence no square number can terminate with A square num- two equal figures, except two fours or two ciphers. cannot ter- Vide cor. to prop. 6. two similar Prop. 6. A square number cannot terminate with more ^oro's U" than three fours. and not with Demonstration. For, if it could end in four fours, such JJJ^ l4san a number might be expressed by a . 104 -f- 4 . 103 -f 4 . 10* + 4 204 ACCOUNT OF CRETINISM. + 4.104- 4; and being- a square number, it would be sweb when divided by 4— thai is to say 25 a . 10* + K)3 -\- IQ* -+- 10 f 1, or its equal (25 rt f- 10) . 1 0a -1- 10* -f 10 -J- 1, or (25 a -f 11) . 10* -f 1.0 + 1, would be a square number. Now it is evident, that (25 a + 11) • 10*, whatever value be given to a, would end with two ciphers; and therefore,, that the whole expression would terminate in two ones, which is impossible by cor. to prop. 5. Q. E. D. No square can Cor. Hence no square number can be contained under ^u.t0feqUa,any n»mher 9j? cq"al digits- Cube6. Scholium. If this speculation be extended to cube nurrjr bers, it will be found, that such numbers may terminate with any of the nine digits, and that it is not therefore so easy to ascertain whether a number be a perfect cube from the nature of its terminating figure. piquadrates. With regard to biquadrate:., or fourth powers, we may observe, that, as these are square numbers also, whatever has beeu demonstrated above relating to square numbers, excepting prop. 1, holds equally true for biquadrates. We may farther remark? that biquadrates terminate in 0, 1, 5, or 6; and that, when they terminate in 0 or 5, their roots will terminate with 0 or 5 a^so: moreover, that when the root terminates in 5, the biquadrate will terminate in 625. XII. Some Account of Cretinism, By Henry Reeve, M. D. of Norwich. Communicated by William Hide Wolla{»- ton, M.D. Sec. U.S.* Cretinism, a -lF ELIX PLATER, in one of his observations, gives the (Specie; of men- history of a species of mental imbecility, which he saw in e^ inalterability at a red heat. I shall begin therefore by describing the precautions, that I took to ensure the perfect purity of the substance on which I was operating. Sect. 1. Preparation of pure Muriate of Barytes. A quantity of crystallized native carbonate of barytes Precautions t» was digested in cokl and dilute muriatic acid, till all efler- ensure its PeT* vescence had ceased, a portion of the carbonate remaining p '' undissolved ; the solution was then filtered and crystallized by rapid evaporation. The salt thus procured was ignited in a platina crucible, and became of a light ochrey yellow from the muriate of iron, that was decomposed. It was then dissolved in cold water and filtered, by which the ox- ide of iron was separated, and the liquor came through quite 302 COMPOSITION OF BARYTIC SALTS. quite limpid and colourless. The solution, being evapo- rated to a pellicle, was decomposed by rectified alcohol, which threw down the muriate of barytes, and retained iu solution the small portion of muriate of stroutian, and any other earthy muriate that might have been casually present. The precipitate, being well washed in alcohol, was after- ward ignited; but being in some degree fouled by a small portion of charcoal from the decomposition of the alcohol, it was redissolved in water, filtered and evaporated to dry- ness, and then ignited. There was thus obtained a salt of a pure white colour, which dissolved in cold water without leaving any residue, and which I consider as pure muriate of barytes. Sect. 2. Proportion of Water in crystallized Muriate of Barytes, Proportion of A quantity of the above muriate was dissolved in warm wator 'n the water, and left to crystallize by spontaneous evaporation. The salt obtained, after being dried by an exposure for several days to the air, weighed 183*25 grs. It was then fully ignited for about an hour, at a heat somewhat less than that required for its fusion, and lost in weight 26*75 grs., which I conclude to be only water, as the residue was perfectly seluble in cold water* In another experiment 100 grs. of crystallized muriate, that had been dried by the heat of boiling water, were re- duced to 85*5 grs. by a heat somewhat inferior to ignition ; being then heated to a low red it weighed a* betore 85*5 grs. ; it was then kept in fusion for about a quarter of an hour, by which it lost less tha» 0*25 gr. "4 5 or 14-6 Hence the water of crystallization in muriate of barytes per cent. amounts to between 14*5 and 14*6% per cent. Sect. 3. Ratio between the Muriate and Carhonate of Barytes, Ratio between 10° grs* °*? ignited muriate were dissolved in water, and decomposed by cavboi edulcorated and dried water, weighed 93 grs. the muriate & decomposed by carbonate of soda. The precipitate, when edulcorated and dried at a heat superior to that of boiling 156-* COMPOSITION OF BARYTIC SALTS. 303 15(>*5 grs. of ignited muriate were decomposed in the same manner, und afforded 146*75 grs. of carbonate, or Q377 per cent. Hence (averaging the results of the two experiments) 100 grs. of ignited muriate afford 03*38 of carbonate: and 100 grs., of carbonate coutain the same quantity of barytes as* 100*6 of ignited muriate. Sect. 4. Composition of Carbonate and Muriate of Darytes. *)3 grs. of carbonate, dried at nearly a red heat, lost 20*5 Composition of grs. of carbonic acid by solution in muriatic acid; or 2-2*04 per cent. 145*5 grs. of carbonate, by similar treatment, lost 31 grs. of carbonic acid, or 21*3 per cent. Hence, on an average, carbonate of barytes consists of the carbonate, 21*67 carbonic acid 78-33 barytes 100. Ignited muriate of barytes consists of ignited muri* ate, 73*14 barytes 26\s6 muriatic acid. 100. And fully crystallized muriate contains crystallized !ai_ ,_ i muriate, 02'47 barytes 22*93 muriatic acid 14*6 water 100. Hence also, ICO of carbonated barytes contain the same quantity of earth as J 24*9 of the crystallized muriate. Sect. 5. Composition of Sulphate of Barytes* 100 grs. of ignited muriate of barytes were added by de- grees to some very pure sulphuric acid in a platina crucible. When the effervescence had subsided, the mixture was gently heated, and the excess of acid was saturated by car- bonate so* *MEM0RIA TBCUNICA FOR ELECTIVE ATTRACTIONS. and sulphate of barytes. Composition according to Klaprotli. benate of ammonia. The whole was evaporated to drvn and then kept at a full red heat for a considerable time after all visible fumes had ceased. The sulphate of barytes thus produced weighed 110*75 grs. Then as 100 grs. of ignited muriate contain 73*14 ba- rytesi ]00 parts of sulphate of barytes contain 6(v04 barytes 33*9*5 sulphuric acid 100. The results of the above experiments nearly correspond with those of Klaproth, according to whom Carbonate of barytes consists of j £* ">**?* *** J (78* 2 barytes. Sulphate of barytes C 33*55 sulphuric acid, GO' -55 barytes. and 100 parts of carbonated barytes yield lc21'04 of cry- stallized muriate. ARTHUR AIKIN. XIV. A Mefkoria Technica for double Elective Attractions. Thomas Young, M.D. F.R.S. Tabic of dou- ble elective at- tractions. By SIR, To Mr. NICHOLSON. Have inserted, at the end of the Syllabus of my Lec- tures on the Elements of the Medical Sciences, a short ta- ble, containing the results of lc260 eases of double elective attractions. For the convenience of those who may wish to retain these results in memory, I have since employed a few leisure moments in expressing the table in the form of tech- nical hexameters. I must beg leave to refer, for an expla- nation of the principles on which the arrangement is founded, as well as for a few particular doubts and excep- tions, to a paper which will appear in the Philosophical Transactions; and I shall at present only observe, that each line expresses a column, of the table; and that when four substances, which stand in any column, are mixed* they will METEOROLOGICAL JOURNAL FOR 1807j$. 3Q£ will arrange themselves in sucb a manner* that the bates : will always be united to the respective ucids which stand nearest to them. I am, Sir, Welbech Street, Your very obedient servant, 22 March, 1809, THOMAS YOUNG. CONTENTIO AQUATICA ; VICTORIA,* ReQUIES. ReBARisne modo posse ad/bre £ellica rosTRa? t)es nautam satis apta ci6o re/bvere aLiMenta ; Cor superest sunum ; f\ab\tq\ie oPTatus abunDe £piritus; has ammi ira/eret iibi acerr'iMA GAZas. Ast BRONfes mnmosus acer^o /bed erepaLMas Csesus fort: utpro rebus monet ap'ra soDales ! Si posshy fato tu&icen iweMor addat honores. Postulat ossd relaia, heu ! flebite c07*dere mArMor. Spes est f\xa, bonum cceli GAzis fruiturum. ALMa huic pax fiat or6i, l&ss'is o/nwipoTens Des O pater! Ut flebo jussus cawere ar/wigenuM vim! Dire opi/ex &elli, cesses wor?«AM abjicere oinnem, Pax fessos bona, wiuleet, GAZas laetior auri. proesuMAM GAZaj nempe ad/ere rursus ab alto hue; Mira da6it lucra pax, foxt&ssis in ulti/HA Muudi. XV. An Abstract of a MeteorologicalJournal for the Years 1807 and 1 808, kept at Middleshaw near Kendal, in Latitude 54° 20'. By John Gough, Esq. Y object in communicating the following table to the The object of Philosophical Journal is, to turn the attention of meteoro- lhe communi* o • i-i cation, logists to two points of their tavourite science, which per- haps have been too superficially examined. One of these points is the diurnal variation of temperature at different times of the year. This is a subject of which we have a very imperfect knowledge; and the reason is obvious: for the variation in question is not easily determined by the common thermometer, at least in summer, because the sun coio- Vol. XXII.— April, 1809. X, moid/ MfiTEOfcOiOGlCAL JOURNAL FOR 1807,8, niohly rises before the observer, and the morning obser- vation is registered at too late an hour. To obviate this irt- Six's thermo- convenience, I made use of the thermometer invented by mended.00"1" Mr# Six ' wmcn> with a little assistance from the observer, gives a correct account of all its variations, by noting edch day the two extremes of its range. Diumal raria- The diurnal variation of temperature determined by this rature mUC" instrument> is certainly more correct than the results of a common thermometer. As for the utility of the inquiry, I have only to observe, that meteorology is at present in its infancy ; and the Cultivators of the science have little to do but to collect facts for the use of their successors. Tables of the kind here recommended, formed in diffe- rent situations and latitudes, will perhaps prove necessary, when the materials of a rational theory have been collected from long observation. In the mean time we know for a certainty, that the phenomenon in question arises from the sun's arinital motion between the tropics: but the influence of this luminary- is disturbed in the regularity Of its effects by the vicissitudes of the weather ; for the variation is great- est when the atmosphere is clear, and least at the same season when the air is obscured with clouds and rain. These are manifestly causes of irregularity ; but they have not suf- ficient power to prevent the necessary consequences of the sun's motion in the ecliptic, they only retard or accelerate his effects. For supposing the Earth to be destitute of an atmosphere, the sun would produce two maxima and two minima of variation at stated times in the course of a year, according to the doctrine of radiant heat. The minima would coincide with the coldest and hottest days, and the maxima would happen after the two equinoxes, perhaps about the times of mean temperature. These extremes ap- pear in the table, but they are not periodical; which is also the case with the hottest and coldest days, as well as the seasons of mean temperature. Rain collected The second subject in meteorology, to which I was de-» at different ele- . ,. j ,, . /»i-,,, vations. sirous to attend, was the comparison ot the ram collected at different elevations, in the same neighbourhood. For this purpose, I made use of two gauges constructed exactly alike ; one of them stood in a garden in the bottom of a vallev, METEOROLOGICAL JOURNAL FOR 1807,8. 3G7 talley, and the Other was placed on the top of a hill almost directly north of the former, and ci yards above it ; a right "line joining the two stations cannot exceed 500 yards. Neg- ligence in one instance* and an accident in another, inter- rupted the series of observations in the first year, but the latter is complete ; and I think the whole goes to prove the results of the two gauges to differ less in summer, than they do in winter. As for the table, no part of it requires to he explained, Table explains except the fifth column, marked Ratio. To form this, the numbers in the third column are multiplied by 1000, and divided by the corresponding numbers in the second; so that the lower exreine of the monthly mean range is invaria- bly denoted by 1000, and the higher by the number, which stands in the fifth column opposite to any particular mouth. cd. Month. 1807. HEIGH Least. T of TH Great. ermom Mean. ETER. L • . Kain in Ratio. jLovr. G. 1 inches. Upp. G. January 31-45 40 06 35*75 1273 2-799 2-517 February 32-6*7 40*71 36-69 1246 4-768 1-468 March 30-29 40*93 35-61 1351 1*798 0 Ui April 37-46 49*56 43-51 1323 2-839 1-804 May 44-82 58-83 51-82 1312 4-5 .»2 3-262 June 48*75 63-28 56-01 1298 2-404 2-031 July 55-11 69-14 62-12 1254 5-310 2-716 August 53-19 66-91 60-05 1257 4-219 3-214 September 40-90 54-16 47-53 13G4 3-014 2*340 October 46-17 53-70 49-93 1163 6-3 82 5'lf,0 November 31-18 38-45 34-81- 1-233 3-62> 2*914 December 30*76 36*93 33-84 | U'OO 2:246 1 1*564 Annual Means. 40-229 51-055 45-642) 1269 Total of R;i ;. 38*631 129-142 X 2 Jau. ■!Oft ON ELECTRICAL ATTRACTIONS AND REPULSIONS. Jan. 1808. 33-06 35-87 34-31 1095 4*725 ' 2-51/ February 31-16 39-76 35*46 1275 2-262 1-468 March 32*43 42-43 37*43 1308 o-rtio 0-122 April 34-51 46-71 40-61 1353 1-804 May 47-53 62-33 54-93 1311 3-692 3-262 June 50*98 64*06 57-97 1256 2-376 2-031 July 55-60 71*52 { 63-o6 1286 3-388 2716 August. 54*36 66-79 ; 6o-57 1228 4-219 3-214 September 48-65 1 59'75 j 54*20 1228 3-014 2-340 October 38*30 47*93 43-11 1251 6-382 5-190 November 37*58 40-98 | 39*28 1090 3-625 2-914 December 33-09 3S-22 35*65 1155 2'246 1-564 Annual Means. 42-10 5T36 46-73 1236 Total. 38-631 129' 142 XVI. An Essay on Electrical Attractions and Repukims; by Mr * "Two mafn?tic xVAY" experiments on magnetism, which give this property M u ids r~ to several needles in opposite directions by a- single electri- cal bhock, led me to doubt the existence of two fluids, which, according to the theory of Mr. Coulomb, repel each other in every section of a magnet. From this doubt arose Aif there two a -^rond. I said to myself, do- electrical repulsions exist •!••( rim! H lids %vlt.hout previous attraction ? in other words, are there two I ., • ' electrical nuuls, possesHug wttn respect to each other the * Jtrorr iue> vol. LXI11, p. 078. repulsive 4>N ELECTRICAL ATTRACTIONS AND REPULSIONS. $()t) pcjra'lsive power of Newton * ? Accordingly 1 took up the fittest modern treatise on electricity, and at the article " Of Repulsions and Attractions," I found six experiments, which are adduced to prove, that this attraction and repul- sion are alternate. I believe, that a double affinity natu- rally explains this alternate movement; and I am per- suaded, that the more we simplify our theories, to account for natural phenomena, the nearer we approach the truth. 1st experiment of Mr. Libes, on attractions and repul- 1st experiment sions, in his new Dictionary of Natural Philosophy, vol. I. ^e^Jac.^' p. 351. tions and re- " Rub with the hand a glass tube, so as to render it per- pli sicfns' ceptibly electrical. Let fall on this tube a bit of foil, down, or any other light body ; it will be attracted, a»d suddenly repelled by the tube. If in this last state of re- pulsion we follow it with the tube, it will fly off with ra- pidity in a given direction ; but if it meet in its course with another conducting body, that is not electrified, it returns immediately to the tube, and afterward suddenly separates from it ; so that if it hung freely suspended by a silk thread between the tube and the foreign body just mentioned, it would fly alternately from one to the other." It is known, that metal has a considerable affinity for the Accounted for electric matter: and it is this affinity, that attracts it to- Jjj?W*O0n ward the tube, the latent electricity of which is not merely excited by the friction, but probably some has been at- tracted from my body to its surface by the same cause; it being drawu toward it, to acquire as much as it can of this- excited fluid. If, while it is in this state, there be any substance near, that has likewise an attraction for the same fluid, and this affinity be sufficiently strong to overcome the gravitation of the foil, it will attract it, seize in its turn the electric fluid, and convey it to the ground, which is equally greedy of it. If the intensity of the foil be still sufficient, to carry it anew toward the tube, these move- ments will continue to alternate, till the attraction of gra- vitation exceeds that of electricity. If there be no con- * Optics, quest. Si : of Theory of the £arth Vy Mr. Delametherie, vol. 111. par, 1314. 4 ducting 310 ON ELECTRICAL ATTRACTIONS AND REPULSIONS. ducting surface to attract the foil, it will be attracted l>y the moisture of the air. The reflections I shall make on the substance of glass to explain the 4th Experiment will serve to account for the down, which is a nonconductor, acquiring in this instance an affinity for the fluid. I do not perceive here any repulsion : for, according to the Author himself, the metallic leaf goes to part with its electricity to the conducting substance. In the electroiner ter with pith balls, that diverge from each other, by which the electrical repulsion is frequently attempted to be proved, these balls separate only because the aqueous va-r pours of the air attract them. This is the reason of the movement of the little pendulum of Henley's electrometer, which I find to be one of the best. In tine, the divergence of all electrometers, as it appears to me, is produced by the attraction of aqueous vapours, or the action of some conducting substance, which attracts leaves and small balls eaturated with electric fluid. 2d Experiment, £d expert- f« Suspend freely to the conductor of an electrical ma- chine a fringe of thread twisted together so as to form a tuft ; and the moment you electrify rhe apparatus, you will see all the threads, that were united together, separate from each other, and this to a greater distance in propor- tion as the electricity is powerful." Ko repulsion. ' Here the air, as with respect to the electrometer, attracts and separates as far as possible the threads. Every natural philosopher no doubt will agree, that the vast evaporation of water, that takes place from the surface of the globe, must impregnate the atmosphere more or less with aqueous vapour, even in what we call dry weather, and that this im- parts to it a great affinity or attraction for the electric fluid. The circumambient air around the electrical machine, therefore, is that which can most readily effect its union vith this fluid. That which is farther off, having the same tendency, must consequently attract toward it as far as pos- jible every substance saturated with it. Hence it follows, that, the more of the fluid every thread has imbibed, fhe mete UN ELECTRICAL ATTRACTIONS AND REPULSIONS. $l\ more will the aqueous attraction act on it, and to the greater distance. 3d Experiment " On a plate of metal five or six inches in diameter put 3d experi- some shreds of gold leaf, and two inches above them let a similar plate of metal be suspended from the conductor, so as to be electrified by it. These little bits of gold leaf will be immediately attracted by the upper plate, and after- ward suddenly repelled to the lower, so that these attrac- tions and repulsions will continue as long as the conductor remains electrified. M To render this experiment the more pleasing," con- tinues our author, " we may substitute for these bits of gold leaf little painted figures, which, alternately attracted and repelled by the upper plate, will appear to dance be- tween the two." This phenomenon, as the preceding experiments, is to be No repulsion, explained by the double play of affinities. These bits of gold leaf, or little figures, are alternately attracted toward the upper plate in consequence of their affiuity for the elec- tric fluid, and toward the lower, which has a communica- tion with the ground, and consequently a reciprocal affi- nity for the fluid, till the conductor no longer contains enough of the fluid to overcome their weight. Lastly, take a fine needle with two points, that can move freely be- tween the two plates, it will raise itself up, and stand erect, till the electricity of the conductor is exhausted. 4th Experiment, To the conductor attach a metal rod terminating in a 4th expert- point. Present to this the inside of a glass, holding it in men ' both hands; then place on a table some balls of pith of el- der, cover them with the glass, and they will immediately begin to leap up against its sides. They will continue do- ing this for some time." In this experiment there is nothing extraordinary, and Explained on . . .,.1-t i ,.l * mi similar princi- it is easily explained m the same manner as the others. 1 he piei substance of glass has the property of setting itself in mo- tion, and then attracting the electric fluid, both by friction and «J]2 ON ELECTRICAL ATTRACTIONS AND REPULSIONS* and communication with another substance saturated with this fluid: but I have observed, that to render it electrical one of its sides must be in immediate contact with a conduct- ing substance communicating directly with the ground. Here the glass held externally between the two hands is nothing more than a Leyden phial : the pith balls are at- tracted by the power of affinity toward its charged sides ; and the table, on which the glass rests, attracts them in its turn. Thus here again we have two attractions; whence the appearance of alternate attraction and repulsion, which continues as in the preceding experiments, as long as the interior sides of the glass are capable of furnishing a super- abundance of fluid. Mr. Delametberie has received from Glass conduc- me a glass conductor twelve or fifteen inches long, which I tor- sent him about six months ago, to give him a slight idea of my large glass conductors. Since that time I have found, that, on holding these little tubes by the middle, and keep- ing them in contact with the prime conductor for a few se- conds while the machine revolves, the whole substance of the glass imbibes the electric fluid like a sponge: that we have time enough to carry the point, which is a little ob- tuse, and had been in contact with the machine, toward the knob of a Leyden phial held in the other hand: and that touching it about twenty times is sufficient to charge it as strongly as by so many sparks from the cap of a good elec- trophones. I have not yet examined the nature of the fluid it gives, a subject that deserves a place in an essay on the Leyden phial, in which I intend to examine whether the phenomena be not more naturally explained by the hypo-, thesis of one fluid, than of two. As the fluid in this case issues from a point, it does not exhibit sparks, but a kind of current, that is extremely brilliant. Must not all these experiments lead us to suspect, that, if glass frequently appear to have no affinity for the electric fluid, it is because its bases, at the time of their uniting in the state of fusion, perfectly neutralise the igaeous matter* ? Consider • Caloric, if you please, as Mr. Libes defines it in the art'de Combined Caloric, which is so interesting and short, *that I cannot refrain from copying it. '• It is that which intimately combines with the particles of bodies, ON ELECTRICAL ATTRACTIONS AtfD REPULSIpNS. gj s. "" __,■ si Bay of < 9 A. M. Night. Day. cr, Ci J*s 25 42 34 45 30 30-26 Fair Fair So" 34 40 44 34 30-44 Ditto Ditto 27 42 42 49 34 30*38 Ditto Ditto 28 38 42 48 38 30'35 Ditto Ditto MAR. 1 43 41 48 30-26 Cloudy * Rain 2 42 38 46 32 30-36 Ditto Fair 3 34 40 42 3'8 30-39 Fair Ditto 4 42 43 46 38 30-16 Ditto Rain 5 41 3a 43 33 30-19 Cloudy Ditto 6' 34 36 40 54 30-26 Ditto Fair 7 34 36 39 33 30*36 Ditto Ditto 8 34 40 37 48 42 51 3*3 42 30-47 Ditto Ditto 9 30-33 Ditto Ditto 10 42 36 50 32 3023 Ditto Ditto 11 34 38 48 32 30*26 Ditto Ditto 12 38 48' 34 30-09 Fair Ditto 13 $6 40 44 37 30-21 Ditto Ditto 14 40 40 44 38 30-24 Ditto Ditto 15 38 42 46 34 30*44 Ditto Cloudy 16 40 44 50 34 30*26 Cloud- Fai r 17 46 50 53 44 30-19 Ditto Ditto is 4$ 46 52 40 30-16' Ditto Ditto 19 44 46* 50 42 30*05 Ditto f Ditto 20 44 45 50 41 29 97 Fair Ditto 21 42 46 50 42 30-24 Ditto Ditto 82 46* 50 58 43 30-09 Ditto Ditto 23 47 52 59 46 2976 Ditto Ditto 24 46' 45 55 42 29*70 Rain Ditto 25 44 43 50 38 29*34 Fair Rain • At 11 beautiful halo surrounding the Moon, f Rain at 11 P.M. ■n o< • I'hihs.hvm/U VoLJMPlJSmJJ/ A JOURNAL OF NATURAL PHILOSOPHY, CHEMISTRY, AND THE ARTS. SUPPLEMENT TO VOL. XXlt. ARTICLE I. An Account of the Chinese Method of propagating Fruit Trees by Abscission, By Dr. James Howison *. • SIR, mft JL HE Chinese, in place of raising fruit trees from seeds Chinese mo. or from grafts, as is the custom in Europe, have adopted \"ixl fruit**" the following method of increasing them. trees. They select a tree of that species which they wish to propagate, and fix upon such a branch as will least hurt or disfigure the tree by its removal. Round this branch, and as near as they can conveniently to its junction witii the trunk, they wind a rope, made of sfraw, besmeared with cow dung, until a ball is formed, five or six times the diameter of the branch. This is in- tended as a bed into which the young roots may shoot. Having performed this part of the operation, they imme- diately under the ball divide the bark down to the wood, for nearly two thirds of the circumference of the branch. A cocoa-nut shell or small pot is then hung over the ball, with a hole in its bottom, so small that water put therein * Trans, of the Soc. of Arts, vol. xxv. p. 14. Vol. XXII. —Supplement. Y %vill 322 METHOD OF PROPAGATING FRUIT TftEfcS. will only fall in drops; by this the rop.e is constantly kepi moist, a circumstance necessary to the easy admission of the young roots, and to the supply of nourishment to the branch from this new channel. During three succeeding weeks, nothing farther is re- quired, except supplying the vessels with water. At the expiration of that period one third of the remaining bark is cut, and the former incision is carried considerably deeper into the wood, as by this time it is expected that some roots have struck into the rope, and are giving their assistance in support of the branch. After a similar period the same operation is repeated, and in about two months from the commencement of the pro- cess, the roots may generally be seen intersecting each other on the surface of the ball, which is a sign, that they are sufficiently advanced to admit of the separation of the branch from the tree. This is best done by sawing it off at the incision, care being taken that the rope, which by this time is nearly rotten, is not shaken off by the motion. The branch is then planted as a young tree. In Europe a It appears probable, that, to succeed with this operation longer time re- jn Europe, a longer period would be necessary, vegetation being much slower in Europe than in India, the chief field of my experiments. I am, however, of opinion, from some trials which I have lately made on cherry trees, that an additional month would be adequate to make up for the deficiency of climate. Advantages of The advantages to be derived from this method are, that this mode. a flirther growth of three or four years is sufficient, when the branches are of any considerable size, to bring them io their full bearing state; whereas, even in India, eight or ten years are necessary with most kinds of fruit trees, if raised from the seed. When at Prince of Wales's Island, I had an opportunity of seeing this proved by experiment. Some orange trees had been raised by a gentleman, from seeds sown in 1786, which had not borne fruit in 1795, while branches taken off by the Chinese mode in 1791, had produced two plen- tiful crops. Whether METHOD OF PROPAGATING FRUIT TREES. 323 Whether forest trees might be propagated in Europe in Applicable to the same manner, I have not had experience sufficient to timber trecs> form a judgment: if it should be found practicable, the ad- vantages from it would be great, as the infancy of trees would, by this means, be done away, a period which, from the slowness of their growth, and the accidents to which they are liable, is the most discouraging to planters. The adoption of this method will, at all events, be of and natives of great use in multiplying such plants as are natives of warmer warm climates- climates, the seeds of which do not arrive here at sufficient maturity, to render them prolific. I have frequently remarked, that such branches of fruit These branch^ trees, as were under the operation of abscission during thebear w*u* time of bearing, were more laden with fruit than any other part of the tree. It appeared to me probable, that this arose from a plethora, or fulness, occasioned by the commu- nication between the trunk and branches through the descending vessels being cut off by the division of the bark, while that by the ligneous circles or ascending vessels, being deeper seated, remains*. The same reasoning accounts stripping fruit for fruit trees producing a greater crop than usual, on being trees of their stripped of their leaves, most of the ascending juices being thrown off by them in perspiration, or expended in their nourishment, for we find that bleeding trees cease to give out their juices after they have put forth their leaves +. I have observed, that the tools from a branch under the operation of abscission were uniformly much longer in shooting into the rope when the tree was in leaf, than the contrary ; hence, the spring season appears most proper for performing this operation. * The circumstances attending the Chinese method of propa- gating fruit trees appear a strong confirmation of Mr. BorAiefs opi- nion, that plants, as well as animals, have a regular circulation of their fluids. f Marsden, in his History of Sumatra, page 119, says, " The natives, when they would force a tree that is backward to produce fruit, strip it of its leaves, by which means the nutritive juices are reserved for that important use, and the blossoms soon show them- selves in abundance." Y2 It 324 METHOD OP PROPAGATING FRUIT TREES* Fruit vritjiout It will seem singular, that the Chinese entertain the same bv dividing the °pini°n that Linna»us did, respecting the pith of trees be- pith of trees, ing essential to the formation of the seed. By cutting into the trunk of the guava tree before it has produced, and making a division in the pith, they have obtained fruit with- out seed. I am, Sir, Your obedient Servant, JAMES HOWISON. Reference to the Engraving, Plate IX, Fig. 1 , of the Chinese Method of propagating Fruit Trees by Abscission. Explanation of A. The tree on which the operation is performed, the plate. g# f\ie straw rope wound in a ball round a branch of the tree. C. The cocoa-nut shell, or vessel, containing the water, which gradually drops thence on the ball below it. D. Another branch of the same tree, from which the part E, rooted in the straw rope or ball, and now ready for planting out, has been separated. F. The vessel suspended from a branch above, and from which the ball has been supplied with water. II. Description of a Gauge or Measure for standing Timber, invented by Mr. James Broad, of Downing Street *. SIR, Standing tim- A HE Instrument I send herewith is for finding the girth ber liable to be 0f standing timber, and will, I flatter myself, be found ex- erroneously, ceedingly useful to all gentlemen, and others having timber to dispose of, and likewise to such purchasers as wish to pay for the true quantity. At present a gentleman having timber to dispose of is liable to be imposed on to a very large amount; for though some surveyors may be found whose eye is pretty accurate, yet this is far from being * Trans, of Soc. of Arts, vol. xxv, p. 18. generally INSTRUMENT FOR MEASURING STANDIN3 TIMBER. 325 ircnerally the case. When an estate is sold on which the "nIe^ me*- ■^ . sured at great timber is to be valued, I believe, there is no other way in expense. general use of finding the girth of a tree (which, being squared and multiplied by its length, gives the contents) than by actually getting up to the middle, where the girth is usually taken, with a ladder or otherwise: a method which is very troublesome and expensive where the quantity is large. The seller has, therefore, noway, but at an enor- mous expense, of finding the real contents of what he has to offer, and as the buyer, if a dealer, from his knowledge is able to form a more accurate judgment, it often happens, that the seller sustains much loss. J have known it ex- ceed 50 per cent. Having some time ago a large quantity to survey, I thought it possible to invent an instrument, which would obviate this inconvenience, and which might be sold at a low price, be correct in its work, quick in ex- ecution, and such as any capacity might use. I likewise thought it might be so contrived, as to make such an allow- ance for bark, as should be agreed on. The instrument I send you possesses all these qualifications, and is susceptible of several improvements, of which I was not aware when I made it, which I will point out at the end of my letter. It is well known, that the diameter and circumference of circles are in a certain proportion to each other, and that double the diameter gives double the circumference. The Allowance for allowance for bark is usually one inch in thirteen, that is, if the greater circumference of a tree with the bark on is found to be thirteen inches, it is supposed it would be only 12 inches if the bark was taken off. The instrument is composed of two straight pieces of well Measuring in- seasoned deal, about thirteen feet long, joined together by scribed. a pin going through them, on which they arc movable; but neither the length nor thickness is of any particular con- sequence, as, by following the directions hereafter given, they may be made of any size. A little way from the larger end is a brass limb, I call the index, on which are engraven figures denoting the quarter-girth in feet and inches. To use this instrument, it is only necessary to take hold of the large end, and apply the other to that part of the tree where you wish to know the girth, opening it so wide as just to touch at 326 INSTRUMENT TOR MEASURING STANDING TIMBER. at the same time both sides of it, without straining it,, keeping the. graduated side of the index uppermost, on -which the girth will be shown, after allowing for the bark, by the inner edge of the brass on the right hand leg. An operation so easy and simple,' that a person of the meanest capacity might measure a great number of trees in a day. Instrument for For taking the height of a tree, I would recommend h«?Shtring thC deal rods °f SCTen feet )on£' ™ac,e so as to fit into ferrils at the end of each other, tapering all the way in the same man- ner as a fishing rod. A set of five of them, with feet marked on them, would enable a man quickly to measure a tree of more than forty feet high, as lie would be able to reach him- self about K'ven feet. Improvements, The improvements it is capable of are, making a joint ^ade™1^ ^ *n tJie arcl1 or scalt'' to cnab,c u to snut UP (when the legs are closed) towards the centre, which would make it easier to carry. Secondly, as it. sometimes happens, that standing timber is sold without any allowance for bark, and at other times with a less allowance than one inch in thirteen, two other scales on the index might be added in such cases, one without any allowance, and the other to allow as might be agreed on. I would have added these, but thought the Society would rather see it in the state in which it has been tried on a large survey, as any artist can with great ease add ■whatever scale he pleases. The present scale allows one inch in thirteen for bark, and is calculated on the following data. The diameter of a circle the quarter circumference of which is 26 inches, is 33 ^% inches. The diameter of a circle, the quarter girth of which is 6f inches, is 872/o inches. To graduate the scale, the instrument is opened so as to take in at the small end between the touching points 8 --J^ inches, and a mark is made on the arch to denote 6 inches quarter girth : it is then opened so as to take in 33 i%% inches, and another mark is then made on the arch, to denote two feet quarter girth ; (these marks are made close to the inner edge of the brass on the right hand limb) : the space between them is then divided into eighteen parts, which represent inches, and are again divided into halves, for half inches; if any notice is to be taken of quarter inches, the eye will easily make a farther decision. I beg MOST PROFITABLE SORT OP SHEEP. 327 J beg leave to add, that it is not my intention to make any for sale. I am, Sir, Your obedient Servant, JAMES BROAD. rence io the Engraving of Mr. James Broad's Machine for measuring standing Timber. Plate IX, Fig. 2. Fig,%. aaaa Two long pieces of well-seasoned wood, Explanation of joined near the middle by a pin b going through them, form- the ^lale" i«fg an axis on which they move, cc Two pieces of brass screwed near their upper ends, on the sides opposite to each other, and projecting over to form the measuring points. d The index fastened to one of the pieces of wood at e, and moving freely under a small bar at /. gg Screws with nuts, placed in the middle of the long slits of the two arms, to wedge them open, whereby the vibration is destroyed, and the arms, though light, are rendered stiff, hhhh Screws and nuts to prevent the arms from splitting. A certificate from Mr. J. Wilkins, carpenter, of Sandy Lane, dated May 4, 1805, stated, that he had used the in- strument invented by Mr. J. Broad, for measuring timber standing, and that he believes it to be a correct and valua- ble one. III. Report of a Committee appointed by the Bath and West of England Society, to investigate the Claim of the Right ' Hon. Lord Somervillc to a Premium " for the greatest Number and most profitable Sort of Sheep*." JL OUR Committee report, that the claim is founded upon facts, as under: About the year 1800, Lord Somerville's stock (as stated Lord Somer- by him in his Memorial to the Society) consisted of forty- ™l,«'»«*k of five ewes of thelong-woolled sort. Finding these annually * Bath Society's Papers, vol". X, p. 71. degenerating, 328 MOST PROFITABLE SORT OF SHEEF. changed for Ryeland. Improved. Mixed with Merino. Profit of South- Downs ; of Ryelands j of South-Down and Merino - of Ryeland and Merino ; Jure Merino. Sire of the tana. degenerating, and also becoming annually less profitable, he changed them at the above-mentioned period for one hundred and fifty Ryeland ewes. In the first year, though the winter was severe, the ewe9 supported themselves tolerably well, and the lambs were in very* good order at weaning time. In their future growth, as wethers and store ewes, they far exceeded in weight their parent stock. One lot of the wethers sold as high as 31. each, and were fed upon grass and hay only. In the following year, Lord Somerville brought from Spain some rams and ewes of the Merino breed. These rams, in each subsequent year, have been, and now conti- nue to be, put to ewes of the South-Down and Ryeland breed ; from each of which crosses a valuable species of sheep has been obtained, both in fleece and carcase ; the re- lative value of which has been detailed by his lordship in his memorial of 1 802, the substance of which is, that South-Down store-ewes at 3 lb. per fleece, and at Is. lQcl. per lb., will pay 5*. 6c?. per fleece; which, at 6J per acre in good upland pasture for seven months, and five months in turnips at 14 or 15 per acre, will pay 38s. or 40*. per acre. Ryeland store-ewes 2f/&, per fleece, at Is. Id. per lb. untrinded, nine sheep per acre, and turnips as above, will pay 2 J. 3$. \0\d. per acre. South-Down and Merino ewes of the half-breed, at 4ib. per fleece clean washed, and 3.?. per lb., will amount to 12*. per fleece- which, at 1\ per acre for seven months, amount to 41. 10s. per acre for the pasture land, with turnips as above for winter keep. Ryeland and Merino ewes of the half blood at 10 per acre for seven months, and turnips as above, at 3- lb. per fleece, and 3.9. 2d. per lb., amount to 61. 10s. bd. per acre. The pure Merino fleeces never sold at less than one guinea each ; the average weight of which has been more than 6 lb. each in the yolk; and on the above allowance of pasture for seven months, and turnips as above in aid of that pas., ture, the return will amount to ten guineas per acre. The size of the farm in Lord Somerville's occupation is four hundred and sixty acres, eighty-fire of which are a dairy MOST PROFITABLE SORT OF SHEEP. 329 dairy unfit for sheep, except for a few couples in the spring. These sheep hare been depastured as under : 56 Acres one and two years old clovers, indif- Feed for sheep. fercnt keep, some worn-out ley. 85 Acres marsh and capital pasture. 35 ditto upland summer pasture. 5 ditto just taken in hand, foul. 7 Keep upon thirty acres of water-meadow for six weeks in the spring, equal to one — fourth the number of acres, or seven. Total - 188 acres; beside the run of thirty-three acres of turnips. But it is to be observed, that in the same Other stock on ground sixteen plough oxen occasionally, but twelve con- sa™e stantly, were depastured; four horses occasionally, four cows constantly, till the after-grass : to this is to be added the run of yearling calves, and a large stock of pigs ; and that the green crops of the spring and summer, 1803, were unusually deficient in these districts. The sheep stock Sheep stock. amounted to 302 lambs, 783 store sheep, Total - 1085 ; The produce of them as follows : Produce. Wool, 12 packs, 1 score - - * with two to assist, in all eight oxen, to constant plough- labour, every day in the year that it was possible for them to work. I consider the attempt of such consequence to the landed interest, so momentous an illustration of the powers of these superior animals in labour, that I beg 2 leave 334 Advantages of oxen in husbandry. leave here to offer him my sincere thanks ; and I have the honour to be, With all respect to the Society, &c. SOMERVILLE. Practical Statement on the foregoing Subject , with Claim of Premium. By John Billingsley, Esq. * Work done by -^ claimant states, that his servant Esau Green has on a team of six a farm of eight hundred acres, the soil of which is of a months. VC Addling texture, ploughed and harrowed, with a team of six oxen and a double-furrow plough, the following acres of land, statute-measure, between the 1st day of January and the 1st of December, 1804, viz. Acres. 56 of oat stubble. 62 of turnips for oats. / 68 of ley. 68 of ley cross-ploughed for a fallow. 100 of fallow, for the purpose of being cleaned after a a slovenly tenant. 19 of vetches. 12 of vetches folded off, and sown with wheat. 385 acres ploughed in eleven months. 56 of oa$ stubble. 62 of turnip sown to oats. 14 of ley. 80 of fallow. 48 of cross-ploughed ley. 19 of vetches. 12 of wheat. 291 acres harrowed in the same eleven months. * Bath Society's papers, vol. x. p. 61. The ADVANTAGES OP OXE\ IS IIUSIlANrDftYi 335 The claimant farther states, that no possible errour can Statement Be- have crept into this statement. No other team being emiCura-** ployed in the tillage of this farm, and the ploughman being paid by the acre. Nor can any doubt arise respecting the Size of the acres, as it is well known, that lands newly en- closed are set out statute-measure. The oxen employed were home-bred, of the long-horned Oxen employ* race, and were purchased last year of one of the claimant's ed' tenants, at the price of 14/. each. Four of them were six years old, and four four years old. Though eight oxen were kept, six only were worked at a time. The other two were changed as occasion required, at the will of the ploughman. These oxen are in no Not injured by respect injured by their labour, and are now in good work- their vrork- ing order. The ploughman and driver were paid Is. Ad. per acre for Price of labour. ploughing, and 6d. per acre for harrowing; and in this was included all necessary attendance on cattle at all times and . seasons. The depth of ploughing from 3 to 5 inches. The breadth of ditto from 7 to 10 inches. As the harrowing was all performed with six oxen, draw- Harrowing;, ing very heavy and long-tined harrows, (provincially called drags) and in many fields two bouts in a place, it will not be unfair to estimate tizo harrowings as equal to one plough- ing ; and in proof of this comparison it may be observed, that the double plough will turn two acres and a half in eight hours, which are half as much as six oxen can harrow in the same time. Presuming that no solid objection can be brought to the Statement of foregoing statement, it may be satisfactory to the society to exPence- see the debtor and creditor sides of the account, methodically arranged, so as to ascertain the cost both of the ploughing *. and harrowing per acre, statute-measure. Dr. Wight Working Oxen, from Jan. 1st to Dec. l,tf, 1804. To 24 lb. of hay per week, consumed between • /}S. g4g or plug, (which requires a considerable degree of force, and too frequently destroys the level of the road) being here un- necessary. In the common mode of making rail-roads, from the irregularity of nails, particularly in forming their heads, few can be driven exactly ©yen with the plate, and they are perpetually obstructing the passage of the waggon ; the workmen frequently not proportioning their holes and plugs to the hole in the block also occasions con- siderable breakage ; the exertion necessary to fix a rail or plate completely is great, and numbers of plates, parti- cularly when the iron is short or brittle, are broken near the mortices by missing the stroke ©f the hammer, which must be used with great force. Advantage gained in laying my Tram-Plates in Comparison with other Modes &. s. tf. Nails used in a mile, 3520 of 3 in the pound, at 4d. per lb. - Nails lost or defective, computed at per mile Plugs with their loss . - - By breakage of rails, average from experience Lessened by labour in block laying, calculated at only two pence per yard By breakage of blocks - This calculation does not take in annual loss of nails, and breakage of blocks, which is considerable. Saving in ex- 19 11 q pense. I 1 0 0 6 5 0 7 10 0 14 23 4 1 0 0 £49 19 4 VIII. Observations 344 FUMIGATIONS TO DESTROY CONTAGION. VIII. Observations on the Use of Acid Fumigations in purifying the Air and stopping the Progress of Contagion, and the most simple Means of completely obtaining this Effect. Extracted from the Correspondence of Mr. Guyton- Morveau *. Contagious dis- A CANNOT yet giVfe you any particulars of the disease, addfumiea- y *na* prevailed at Pethiviers at the end of last summer; tions. though several persons, who have seen the reports of the officers of health, have assured me, as I informed you at ^ the time, that acid fumigations had evidently put an end to it. I shall say nothing of what may have prevented the re- sult from being published, or why it has not even been men- tioned in the newspapers. You will scarcely believe, that indifference could be carried so far on a subject of such im- Obstructions to portance. No doubt it would-be otherwise, if government improvements. appeare(j to set any value on the discovery: but there are so many petty interests, that -oppose its utility being made known; and it is so much more easy for a man to throw a veil over the efficacy of the means, than to confess himself H chargeable of having been ignorant of them, or of having neglected to apply them to the benefit of mankind ! Infectious dis- I have been informed, that a physician in considerable eases anse repute asserted a few days ago, that these fumigations were •without direct r J ° 7 ~ . contagion. inefficacious against diseases not communicated by infection. It would not have been amiss to have asked him, whether he thought balls and bayonets conveyed any infectious prin- ciples: or whether he did not know, that, whenever a great number of wounded persons were conveyed to an hospital, a disease did not soon break out, that attacked the nurses, the medical attendants, and often a whole town. For, as I have said on a former occasion, whatever be the first cause or the nature of a disease, that affects several individuals at Hospital fever, the same time, it necessarily produces an hospital fever, which ultimately occasions more ravage than the original disorder; and it is precisely against this scourge, that mine- * Annales de Chimie, vol. xlvi, p. 1 14. ral FUMIGATIONS TO DESTROY CONTAGION. 345 ral acid fumigations afford a certain preservative, a remedy " the efficacy of which can no longer be disputed. The more secret motives there are, to mislead opinion on Testimonies collected by this subject, the more incumbent on me it is, to collect such jyir Guyton. facts as testimonies, as may produce conviction. I have at present some to communicate to you, which cannot fail to appear capable of making an impression on all those, who are not misled by prejudice; and I will add some remarks fon the bottles for destroying contagion, which are not yet sufficiently known, and the method of employing them for the use of a large hospital, so as to have always at hand, without trouble or expense, a certain preservative, and a powerful stimulus, the strength of which may be regulated at pleasure. Letter from Dr. Mojon. Dr. Mojon, professor of chemistry and member of the At 9en?a ac?d Medical Society at Genoa, who h.id already furnished me employed with some valuable information respecting the use of mine-a£amst ral acid fumigations in that city, which makes a part of the additions to the second edition of my treatise, has since addressed* to me the following letter. " As soon as we perceived the progress of the epidemic an ePidemic fever, recourse was had to the acid fumigations in our churches, hospitals, lazarettoes, prisons, and barracks, and in the chambers of several sick persons. " On the 20th of March, 1800^ was sent for to St. An- in a church .. , , , . . against noxious drew's church, where two grave-diggers had dropped dead, effluvia, just as they were going down into a vault. I found the church offensive with putrid exhalations ; and immediately directed the vault to be walled up. After causing the win- , dows to be shut, I placert in the midst of the church a large earthen vessel containing six pounds of common salt, and three of sulphuric acid. Some lighted faggots were placed round the vessel, to accelerate the extrication of the va- pours, which ceased at the expiration of two hours, and then the windows were opened. The noisome smell was completely gone, and the church was used as before, with- out any thing offensive being perceived. " I ob- 346 FUMIGATIONS TO DESTROY COXTAGIOX. in a very large ehurch, and in the chambers of the sick. Acetic acid used as a pre- servative. " I observed the same effect still more strikingly, when I employed oxigenized muriatic acid fumigations in the largest edifices, particularly in St. Dominic's church, -where the air was so noisome, and so loaded with putrid emanations, that its stench was perceptible to some distance and in the adja- cent houses. For this fumigation I employed eight pounds of salt, four pounds of sulphuric acid, and a pound and half of black oxide of manganese. u To purify the air of close and habited houses, I pre. ferred fumigations with nitric acid, which were equally suc- cessful, destroying the contagious miasmata without occa. sioning the least inconvenience to the sick. There is no in- stance of any one having caught infection from a sick per- son, where these fumigations were constantly used. " To secure myself from the effects of the putrid and contagious exhalations, to which I was daily exposed, J made use of no other prophylactic than a small phial of acetic acid (radical vinegar), which I held to my nose, and hy its means I had the happiness of escaping the infection during the whole continuance of the epidemic." Effects of Fumigations with oxigenheel Muriatic-Acid, a* reported by Mr. Fleury, Officer of Health in the Navy. Mr. J. A. Fleury, in his Essay on the Dysentery, pre- sented to the School of Physic, January the 4th, 1803, Oximmiatic acid fumiga- te™! m XS6 " after classing frequent fumigations with oxigenized muriatic acid among the general means of regimen and renovation of the air, adds what follows as a note in support of this pre- cept. and against the " After the signature of the preliminaries of peace and hospital soie. ^ trcaty 0f Amiens, a great number of French prisoners landed at Cherbourg. The sick were carried to the naval hospital, of which I had the charge. Several were afflicted with the ulcer called the hospital sore, to remedy which all the resources of physic and surgery were employed in vain. The fumigations of oxigenized muriatic acid, employed ha- bitually to correct the air, were particularly directed to these ulcers; and soon the contagion, which imparted to other ulcers and recent wounds the same character, was stopped. FUMIGATIONS TO DESTROY CONTAGION. 347 .stopped, and I had the satisfaction to see cures gradually effected, which 1 had before attempted iti vain. Though these fumigations were made in wards full of patients, from the impossibility of avoiding it, and this rendered their more frequent employment necessary, I never found one person complain of them, or sensiblyincommoded by them. It was not the same with those, who entered when the va- pour was already in a state of expansion ; as it brought on these a violent cough, and obliged them to quit the ward immediately.,, * On the Preparatiom and Use of the Phials for removing Contagion, The phials for preventing and removing contagion, which Phials for pre- I have mentioned in my treatise, have become pretty com-^"vJ"^ eonta^" mon, since they have been kept ready prepared in the shop gion. of Mr. Boullay. In fact it is not easy to conceive any- thing more simple in its preparation,' more convenient for use, and less expensive, considering the property this com- position has of retaining its virtue a long time. I have one of these phials prepared near twelve years ago, and it can- not now be uncorked, without the persons present being immediately sensible of the oxigenized muriatic acid gas, though I have used it on various occasions, ancino addition has been made to it since it was first prepared. This is the property of what I call extemporaneous oxigenized muriatic acid, because it is made in an instant, without the aid of fire or any apparatus for distillation, in short by simple mixture. However easy this process is, certain proportions are ne-The ingredients vertheless necessary to be observed, in order that the evo- mus.t be accu" J ' rately propor- lution of the gas may be sufficiently abundant to be eflica- tioned. cious, yet not so rapid as to burst the vessel : and it is ob- vious, that the proportions do not depend simply on the relative quantities of the acids in this case, but still much more on their degree of concentration. Several persons, having seen the stopples of these phials rise spontaneously the moment they opened them, Were alarmed, and mentioned it to Mr. Boulay ; who accordingly thought it necessary to dilute the mixture, that it might be less 348 FUMIGATIONS TO DKSTROY CONTAGION. less active. Soon after this I was informed, that phials re- cently bought of him scarcely made any impression on the nose when opened under it; and some were brought nit", from which I found in fact but a slight smell of common muriatic acid. On my representing this immediately to Mr. Boulay, he at once made his phials as strong as they ought to be; and I know, that those he has since sold were well prepared. This however suggested tome, that it might be proper, to determine the process with more precision than I had hitherto done, I mean with regard to weight and measure, in order to have a liquid at all times manageable, and of a permanent degree of activity. I shall proceed therefore to give the receipt with all its particulars. The phials de- The phials to be made portable should scarcely exceed in scribed. capacity A\ centilitres [l|oz.], or 45 cubic centimetres [about 2 J cubic inches]. This is the measure of those pre- pared by Mr. Boulay, who puts them into a case of hard wood, commonly of box, neatly made. The cap of this case screws on. It is unnecessary to say, that the stopple of the phial must be of glass, and ground to fit perfectly tight. Method of pre- Having selected a phial, it is to be measured. Suppose paring them ;ts capacity to be just 45 cub. cent. [Hoz.], 3 gr. [46-32 grains] of black oxide of manganese are to be put into it, * powdered, but not finely, and sifted only through a hair sieve. To these add 7-5 cub. centim. [about {of a cubic inch] or | of a centilitre [| of an oz.] of pure nitric acid of the specific gravity of 1*4 (about 39° of Baume's areometer), and an equal measure of muriatic acid of the specific gravity of 1*134 (about 17° of Baume's areometer). The stopple being put in, the process is finished. They must not I* 's *° 0e observed, that about two thirds of the capacity be more than 0f the phial will thus remain empty. This is an essential condition, without which it is impossible to confine the gas. Having once exceeded this proportion in a very strong ilint- glass phial, that would hold 4 decil. ,[13 oz.], I saw the stopple, which weighed 122 gram. [1881 grs.], driven out to such a height, that in falling it broke the phial. But it is easy to prevent all accidents, by keeping within the limits here assigned. It FUMIGATIONS TO DESTROY CONTAGION. 349 It will not be improper, to add to the instructions for - preparing these phials the manner of using them ; for things acquire value only by the skill with which they are used. In the first place it is to be observed, that the intention Manner of of the screw is chiefly to bring the cap of the case to the usnig l em* proper point for confining the stopple of the phial; which might otherwise be raised up by the expansion of the va- pour, and allow the acid to escape; so that, if you were to endeavour to turn the screw as far as it would go, or even if you were to turn it with too much force, you would ne- cessarily split the cap, or even crack the neck of the phial, which would be still more dangerous, if it were not imme- diately perceived. I have observed, that the first thing done by those who Caution, are unacquainted with the nature of acid gasses is, to apply the phial to the nose, as they would a smelling bottle ; whence they feel an irritation so much the more painful, because it is more quickly carried to its maximum. It is necessary therefore, to inform such persons, that the phial for destroy- ing contagion should not be brought near the nose: on the contrary, it should be kept at a distance from it when it is unstopped; and when it begins to make an impression on the olfactory nerves, it is time to stop it again, unless it be required to render the fumigation efficacious in a given •pace, as when the object is to purify a chamber rendered noisome by putrid efliuvia. In this the phial should be placed on a table, and left unstopped for some minutes. With these precautions we may obtain all its good effects, without experiencing the least inconvenience. So much for the use of the portable phials : you will soon see, that I have carried my views much farther respecting the advantages to be derived from the preparation they contain. Permanent Apparatus for destroying Contagi&n in Hospi- tals, public Places, cj*c. It is with some unwillingness I employ the word appura- Permanent ap- ius, which may perhaps be sufficient to frighten many per- J^b^Tii 350 JUMIGATIONS TO DESTROY CONTAGION. ions, though in fact it is applied only to a vessel kept ready to be opened when necessary, and which in this view might be called a box of salubrity ; but the name is of little im- portance, and I leave it to custom to settle this, so the thing itself be adopted. In reciting the numerous experiments I made in one of our hottest summers on considerable bodies of air contami- nated by sanious putrefaction, I announced, that I took the precaution frequently to leave open in my laboratory a very large phial, containing the mixture above mentioned for the extemporaneous production of oxigenized muriatic The mixture acid gas. This phial, which had since been neglected, hav- SSSoxhniwi- *nS fallen m my wav a few tojfa a§°> I was surprised, on atic acid gas a taking out thestopplc, at the strength of the gas it still fur- long wi e. njshed after the expiration of two years. This convinced ' me, that the mixture, kept in sufficient quantity in large vessels, would supply the place of all fumigations to destroy contagion, and answer the purpose as effectually, without trouble, expense, or inconvenience, and without its being necessary to renew the preparation till after a considerable time, even in cases where it would be most frequently ne- cessary to give issue to the gas. Necessary con- ^ *s ODVi°us? that the capacity of the vessel must be pro- ditions. portionate to the extent of the space to be purified, and its aperture sufficiently large, to give instantly the volume of gas required; that is to say, so as to extend to every part, without too powerfully affecting those who are nearest to it. .Lastly, the gas must be so confined, that it cannot burst out, or even escape imperceptibly : in a word, so that it will only diffuse itself around when we wish it, cease to be diffused at pleasure, and remain for months without its pre- sence being suspected. Easily obtain- ^ these conditions are easily obtainable for the largest able. hospital ward by the means 1 am about to describe. Apparatus de- Take one of those very thick flint glass tumbers, which scribed. are comm(m in the shops, of 11 or 12 cent. [4*3 or 4-7 inches] high, and 10 ^3'9 in.^ in diameter; holding about 7 decil. [i*47 wine pint]. Grind the edge so that it may be closed by apiece of plate glass. Cement the bottom of the tumbler into a piece of wood, which is to be made fast by FUMIGATIONS TO DESTROY CONTAGION. 351 by sliding horizontally into grooves at the bottom of two uprights. To these uprights a cap must be fixed, through which passes a screw, to raise or lower the stopple by means of a nut in a sliding cap, to which the piece of plate glass is to be cemented. An inspection of the figures, PI. X, Figs. 5 and 6, will show the form and dimensions of every part of this little apparatus, which should be wholly of wood, without iron or any other metal, and the construction of which requires nothing extraordinary or at all expensive. A a small square of wood, into which are fixed the two uprights, B B. C a glass tumbler, cemented into a little movable piece of wood, rf, which is secured by a groove in each of the uprights. E a wooden screw, passing through the upper cross piece F, and carrying the movable cross piece G, which slides on the two uprights by means of a groove at each end. 11 the plate of glass performing the office of a stopple, and cemented to the under side of the movable cross piece. The vessel being thus arranged, and its capacity being we will suppose 7 decil. [near l\ pint], pour in first a de- cilitre [3\3G9 oz.] of nitric acid, of the strength mentioned above, and then an equal quantity of muriatic acid ; add 40 gram. [618 grs.] of black oxide of manganese pow- dered; and immediately close the vessel by screwing down the stopple. These proportions are assigned from the ne- cessity of leaving at least two thirds of the capacity of the tumbler empty. If the contagion were considerable, or if the foci from In large or very which it issued were sufficiently numerous, to renew it in a foul Places two * or more neces- short time, H would be advisable to have two or three such sary. apparatuses in the length of the ward. In a place less extensive than I have hitherto supposed, In some ca>es j- ... i t j a large wide in a ward for instance containing but ten or twelve beds, or mouthed phial in- a public room where the air is vitiated only by a tempo- suflkient. rary accumulation of animal effluvia," we might employ, in- i itead of one of these tumblers, a wide mouthed stopple bottle, such as the glassmen sell for the use of chemists. Their 355 FUMIGATIONS TO DESTROY CONTAGION* Their capacity is commonly about 40 or 45 centil. [14 or 15 oz.] ; and their stopples, which are made to fit tight, arc 3 cent. [1*18 inch] or more in diameter. It is obvious, that by putting into one of these phials 6 centil. [2*22 oz.] of each of the two acids, and 24 gram. [370 grs.] of black oxide of manganese, we shall readily obtain a reservoir of gas for destroying infection. The only thing to be apprehended, against which the apparatus above described is secure, is that the stopple, being secured only by its weight and the friction of the neck, should be forced out by the elasticity of the gas: but this maybe pre- vented by loading the stopple with a heavy cap of lead. Method of No farther direction need be given respecting the mode of using them, using these reservoirs of gas for destroying contagion, than to open them when it is deemed requisite, and to close them as soon as the persons nearest at hand begin to be affected by them. After this we may rely on the spontaneous ex- pansion of the portion set at liberty. The effect will be such, that, if the vessel have remained open only four or five minutes, those who come into the room an hour after by the remotest door will immediately perceive, that oxigen- ized muriatic acid gas has been extricated. Advantages of You will be of opinion assuredly, that of all the pro- the oxununatic cesses adopted for fumigation this is the most simple, the least liable to accident, and the best adapted to common use: and when you consider, that the gas it sets inaction is acknowledged to be the most efficacious, even by those who have appeared to dread its activity, because they were unacquainted with the means of moderating it at will; and lastly, if you adopt the decided opinion of several profes- sional gentlemen, that this gas has the property of exciting the vital powers above all other acidgasses; you will per- haps think with me, that when the petty passions are ex- hausted by struggling against conviction, the oxigenized muriatic acid gas will be adopted in preference as the pri- mary antidote to contagion, and its extemporaneous pre- paration will be the most common resource in the regimen of health. IX. Account FILTRATING WELL FOR RAIN-WATER. 358 IX. Account of a Well for preserving and filtering Rain-water for domestic Purposes, where a Supply of Spring-wate-r was not easily to be obtained. Communicated by J. R. Go wen, Esq. To Mr. NICHOLSON, SIR, Y OU may perhaps deem the following account of a fil- Well for nltra. lering rain-water well, which has been successfully tried tmgrainw*ter* here by the Earl of Caernarvon, not undeserving of notice in your valuable Journal. His lordship has lately erected, upon a dry gravelly eminence in his park, an ornamental circular building, consisting of a room and open colon- nades above, and apartments for cottagers upon the base- ment floor. Considerable .discussion arose upon the mode Difficulty of of supplying them with water, from the great depth to t"rPon m? emi- which it was necessary to sink, in order to obtain an dice- acnce* tive well. My friend, Mr. John Loat, builder, of Clap- ham, who had furnished the plan for the construction of the dome roof, mentioned to me a contrivance of his fa- ther's to meet a similar difficulty, which had been attended with invariable success, and Lord Caernarvon immediately determined upon carrying it into execution. Following Mr. Loafs instructions, we sunk two wells, obviated by SO feet deep by 4 feet diameter each, which for greater co11^"? «"*• r J 7 ° water m one perspicuity I shall call No. 1 and 2. i hey are a trifling well and filtra- distance asunder, and were carefully clayed, to prevent per- tl"» lt mt0 an" eolation into the surrounding soil, and lined with bricks in the usual manner. A well secured communication was made between the two wells, by a small leaden pipe inserted two feet from the bottom. All the pipes from the roof were directed into No. 1 ; and an oak floor, bored full of small holes, and supported upon posts, was laid in at No. 2, just above the pipe of communication. Upon this floor was first placed a stratum of well washed coarse gravel, then one of liner, next a stratum of coarse sand, and finally Vol. XXII. — Supplement. 2 A on* ,jj± O* THE stkucture OF seed*. one of the finest sand \vc could procure, making altogether two feet in thickness of sijjcious substances. The water, which is received into No. 1, passes through the leaden pipe into No. 2, and filtrates by ascent through the strata of sand and gravel, the space below the level of the oak floor in both wells, acting as a qespoolj receives all sediment. The pump is of course affixed in the filtering well. Both wells arc covered up, but plenty of air is admitted to them, through apertures made for thh purpose. Advantages of You will immediately perceive, that the merit of jtjiis plan * P au" consists altogether in the filtration by ascent, with a compe- tent space under the apparatus. The interstices of the sand are thus never clogged, and its power is preserved unim- paired for an indefinite period. The well fully answers its intended purpose, and tjie water is altogether excellent. I have been tempted to submit this statement to you from a persuasion, that there are few houses, which may not be made in this maimer to supply excellent water in sufficient quantity for domestic consumption; and that situations abound, where the filtrating well may be resorted to with equal comfort and advantage. I am, Sir, Your obedient humble Servant, J. R. GOWEN. Highclere, Nezebury, Berks i April 1, 1809. X. An Inquiry into the Structure of Seeds, and especially into the true Nature of that Part called by Gocrtncr the Vi- tellus. By James Edward Smith, M.D. F.R.S. P.L.S.* Partner first IjrjERTNER, so justly celebrated for his anatomical and named and de- physiological inquiries into the nature of seeds in general, JuSt and for his particular illustration of one thousand different kinds, claims the merit of first giving a name and definition, * Trans, of the Linnean Society, vol. xx, p. 204. to Off THE STRUCTURE OE SEEDS. 355 . to a part called by him the vitellus, which, though not en- tirely unobserved by preceding philosophers, had received no particular description or explanation. Before we enter upon the investigation of this organ, it is necessary to con- sider the structure and functions of the parts of a seed in general ; and this it will be best to do physiologically. Three agents are necessary to the germination of seeds, — Germination of moisture, heat, and air. A seed committed to the ground mature "heat, absorbs, through the vessels of its base, the juices of the and air. soil, or any other moisture that comes in its way ; while it receives, throughout its whole substance, a definite portion of heat, some seeds requiring a greater share of the latter, for the purposes of vegetation, than others. Moisture and lieat however are not of themselves sufficient to cause the germination of seeds. It has long been known, that air is equally necessary ; and modern chemists have ascertained oxigen gas to be the particular ingredient of the atmospheric air which is requisite, and which is absorbed by seeds, in the moments of incipient germination, from or through the ** surrounding soil. Thus the bulk of the seed is increased, and its vital principle stimulated. It bursts its immediate Integument, integument, or testa, and in the first place sends forth the radicle, or young root, into the ground. This part being, as Dr. Darwin well observes, most sus- Radicle. ceptible of the stimulus of moisture, elongates itself in the direction in which it meets with this stimulus ; and descend- ing into the earth, while it fixes the infant plant, assumes its own proper function of imbibing nourishment for the fu- ture support of that plant. But before any supplies can be thus obtained, consider- Albumen. able demands are made, even by the root itself; and not only an evolution of parts, but likewise an increase of bulk, takes place in the young vegetable. For this necessary pur- pose a store is prepared in the albumen, a substance either constituting a separate body by itself, as in grasses, corn, palms, &c, which, from a hard, dry, and tasteless mass, changes, by the action of water and oxigen, into a milky or saccharine fluid ; or the same substance is lodged in, or united with, the bulk of another part, next to be mentioned, the co* tyledon, or, as they are generally of the plural number, cotyledons. 2 A 2 As 3j5 on the structure of seeds. Cotyledons. As the root is the part stimulated by moisture, the coty- ledons appear to be most stimulated by air, and they conse- quently raise themselves, for the most part, out of the ground in order to receive it, in the form of seminal leaves, well known to perform, for a time, the functions of real leaves, and even, by the actiou of light, to assume their green co- lour. The albumen cannot be said to be stimulated, or acted upon as a living body, by the air or gas, which only produces chemical changes in it; and the destination of this substance being soon accomplished, it disappears by ab- sorption. Not so the other parts of the seed, one of which becomes the still descending root, the other the nurse, or, if we may say so, the foster brother of the young ascend- ing plant, which last originates from the extremity of the embryo opposite to the root, but. always, like that, most intimately connected with the cotyledons. These indeed, sooner or later, wither away; when the acquisition of real and more ample foliage renders them snperiiuous, or no longer necessary. But all cotyledons do not ascend out of the earth, nor assume any of those functions of leaves in which light is concerned. In the horse chesnut, the cyamus nelumbo, the tropmolum majus, and some other plants, they always remain buried, no doubt acted upon by the air or gas alone. Even in plants of the same natural order, pa- pt'lionacece, some, as lupinus, raise their cotyledons into the air and light, in the form of very conspicuous green ■•eed-leaves ; while others, as lathyrus, retain them under ground, concealed in the black skin of the seed, quite out of the reach of every ray of the latter. In these we knowr a farinaceous albumen is lodged, whether they rise into the fight or not; and the closest analogy leads us to conclude, that their functions are otherwise similar, which can only be wiia respect to air. M t indisnensa- Even cotyledons however are not indispensably requisite i»l«*. to a seed, though the albumen appears to be, in some form or other, necessary to all seeds. Not to mention the tribes of ve* getables allowed or guessed to be without cotyledons, and thence, for systematical convenience, denominated acotyledo- \bsent in nous.; all, who have sufficiently considered the matter, know plants called jna( jn those called roonocotyledonous, what is vulgarly taken moiiocotyledo- * ROUS. * * OX THE STRUCTURE OF SF.r.DS. 3:*7 for the cotyledon is really an albumen, a part fundamentally ' distinct in functions from what is proper to a cotyledon. Thus even so conspicuous a family of plants as the orchidea; which the faithful Jussieu confesses were ouly presumed from analogy to be monocotyledouons, or, as he guardedly expresses it, to have " a single-Iobed '6yrcuiUm^V have been shown by Mr. Salisbury, in the eighth volume of our Trans* actions, the only person I believe who has well examined their germination, to have in fact an albumen, but no coty- ledon at all. Nor does such ambiguity or uncertainty be- long to this family alone. Many plants are presumed to be monocotyledonous, chiefly because they grow in the water ; and it is much to be regretted, that this fundamental prin- ciple of all natural systems should in many cases be so ill- established, and very often so extremely difficult to detect or to determine ; which happens in general where its help is most wanted, as I shall presently endeavour to show ; but I must first speak of the more immediate object of the present essay. Gaertner asserts the vitellus of seeds to be u distinct from Vitellus. c< the cotyledons as well as from the albumen, and, for the u most part, situate between the latter and the embryo." He considers as its principal diagnostics the three following Its characters characters : " 1st, that it is most closely connected with the ^[^ to u embryo, so as not to be separable from it without injury H to its own substance: 2dly, that notwithstanding this in- u timatc connection, it never rises out of the integuments W of the seed, as the cotyledons usually do, in germination, u so as to become a seminal leaf, but, rather like the al- u bumen, its whole substance is destroyed by the seedling " plant, and converted into its own nourishment : and 3dly, " that if the albumen be likewise present, the vitellus is al- c< ways situate betwixt that and the embryo, iu such aman- " ner, however, that it may be separated from the albumen M with great ease and without injury." For which reasons this able writer considers the organ in question as " allied u on the one hand to the albumen, on the other to the co- M tyledons," but truly distinct in nature from hoth. He proceeds to observe, that " it is of all the internal parts of u a seed the most singular, and by far the most unfre- " tiuent." Now, 358 OS TIIE STRUCTURE OP SEEDS. These do not Now, to consider all these points separately, in the 1st hoId* place the vitellus is not more closely connected with the em- bryo than the greater part of cotyledons are; according to the figures and descriptions of Gartner himself, the fidelity of which must be evident to any one in the habit of using his book, and especially to those who will take the trouble of comparing a few of them with the seeds to which they refer, while in the earliest stage of germination, at which time the relative connection of the parts is best ascertained. 2dly, That the vitellus never rises out of the ground, is a circumstance common to it with many cotyledons, allowed to be such by Gartner, as in the leguminous plants, and /. others already mentioned. 3dly, That the vitellus is situ- ate between the albumen (if the latter be present 'as a se- parate organ) and the embryo, is only a necessary conse- quence of the more intimate connection between it and the latter than either of them has with any other part, which is also precisely true of the cotyledons and embryo, as above mentioned. It does not dif- For these reasons I presume the vitellus to differ in no re- fer from the spect from the subterraneous cotyledons already -described;, cotyledons. anu" tnat its office is to perform the necessary functions rela- tive to air or oxigen, till the leaves come forth and assume those functions, in greater perfection, with the cooperation of light. This seems more satisfactory than the opinion of Gaertner, that the organ under consideration affords nou- rishment to the embryo; because tjiis is abundantly supplied by the copious albumen of a multitude of seeds, the viteL lus of which is very inconsiderable, as grasses ; and be- cause it is unphilosophical to recur to two causes, when one is evidently sufficient. In fact, the vitellus^ as far as I can observe, only dwindles away when the leaves unfold, exactly as happens to the subterraneous cotyledons. The game thing very often takes place as speedily in those which rise out of the ground ; the existence of the latter appear- ing to be prolonged in some instances, merely by their nearer approach to the nature of leaves, as in umbelliferous and cruciform plants. Tbe difference of duration is still more evident, and more instructive as to our present purpose, in the leguminous family, between such cotyledons as rise above ON TIIE STRUCTURE OP SEF.DS. 359 above (he ground, like lupines, and those which remain buried, like vetches, the latter decaying as quickly as any supposed vitellus can do. In grasses the scale, taken by The scale of Gacrtncr for a vitellus, is mostly so thin and unsubstantial, ^^^ as not possibly to contain any material portion of nourish- in its functions, riierit; but its expanded figure is very well calculated, like that of the leaves, for functions analogous to vegetable res- piration, and its whole aspect conveys the idea of a primary or subterraneous leaf, quickly rendered superfluous by the production of real leaves, which, as well as the radicle, are probably, in the first stage of their evolution, fed by the abundant juices of the albumen. It appears, that the pre- tended vitellus is not necessary to all plants furnished with this distinct kind of albumen. The palms and orchideos prove to be destitute of it. On the other hand, I can find Vitellus nev«*r no instance of a supposed vitellus, and a real cotyledon dr cotyledon, cotyledons, in the same plant. What Gartner terms the cotyledons of rhizopkora, in his tab. 45, appears to me to be the plumula ; and in his descriptions of some of the.?c/- t a mincai, he evidently takes the latter for a cotyledon. \ly understanding the vitellus as a cotyledon, all ambigu- Considered as s ity respecting the component parts of any seed is removed, cotyledon. When the cotyledons arc two or more, the only question is, whether the albuminous matter is lodged in their substance, or whether it forms a separate organ. When the embryo is accompanied by a simple undivided organ or seed-lobe, we know it to be a cotyledon by its strict union, or even par- tial incorporation, with the embryo, as in zcwiia*; whereas the pure separate albumen of the true palms has, as in every other instance, no more connection with the embryo, ac- cording- to Gartner's just remark, than is absolutely ne- cessary : and moreover evinces its true nature by the che- mical alteration, and speedy absorption, of its whole sub- stance. The cotyledon, as I considerit, of zamia, as in * Mr. R. Brown, who has observed the germination of a large species of zamia in New Holland, assures me that he found no such incorporation of the parts in question as Gaertner has repre- sented in his t. 3, and that the structure and evolution of even part bore an exact resemblance to cycus us described by Mr. Aubert iiu Petit Thouars. numerous 360 . OS THE STRUCTURE OP SEEDS. numerous parallel instances, shrivels and shrinks indeed con- siderably, from the absorption of its albuminous contents by the vegetating embryo, but does not disappear, leaving only a skin behind, like the albumen of grasses or corn, bo- cause that part of its substance, which is destined to perform the office, essential to a cotyledon, concerning air, merely decays when its end is answered. Difference in It may further be observed upon this subject, that the the albumen, albuminous matter of seeds with two or more cotyledons is commonly of an oily nature, while those with one cotyledon, or none at all, have a more farinaceous, or even stony, al- bumen. Still the latter changes to a milky or oily tluid, previous to its absorption. When the vital principle of a seed is extinct, its albuminous oil becomes rancid, and, even in seeds that retain life, is liable to suffer some dete- rioration by keeping. Hence, as Darwin observes, gar- deners preserve melon and cucumber seeds, perhaps for years, that the plants they produce may be less luxuriant, in consequence of being starved at their first germination ; for any injury to the cotyledons, even after they begin to rise above ground, is found to cramp the subsequent growth of the plant. Oil of the eo- The oil of the cotyledons has been usually supposed a tyledons. protection to their internal parts, I presume against wet ; but this purpose it by no means does or can answer, for all seeds readily absorb moisture whenever they meet with it, and, if likewise exposed to the action of oxigen, they ve- getate, in whatever situation they may otherwise happen to be. I suspect moreover that the oily and mucilaginous flu- ids of seeds in general, before they perform their office in germination, all previously become milky, and often sac- Would oxipen charine, from the actions of water and oxigen. It might preserve seeds foe worth while to inquire, whether exposure of such seeds prone to turn . . - nwcid ? as are most prone to turn rancid, to a quantity of oxigen, would fend to preserve them. It is, I believe, found, that the admission of some atmospheric air is necessary to the preservation of many seeds. The primary cause of decay therefore in seeds spoiled by keeping may originate, not, as I have supposed, in the extinction of their vital principle, but in the corruption of their albuminous oils ; and this is strengthened ON THE STRUCTURE OP SEEDS. 361 strengthened by the experiments of the French, chemists, whose applications may much more readily be supposed to correct and restore the albuminous juices, than to bring the dead to life. This idea of the albuminous matter, whether oily, muci- The albumen, laarinous, or farinaceous, being, when not a distinct andwhen "ot a«e" ° > 7 o? parate body, separate body, always lodged in the cotyledons, throws ad- lodged in the ditional light on the nature of the last mentioned parts, and Cotyledtta8* in a very beautiful manner confirms their analogy with leaves. The discoveries of Mr. Knight have proved, that the nu- tritious fluid or sap of plants is carried into the leaves, in order to be there acted upon by air, light, heat, and mois- ture. After these agents have produced their effects, the fluids are sent back, through the returning vessels, into the branch or stem, to furnish matter of increase to the whole vegetable body. The chemical experiments, of Dr. Priest- ley more especially, confirm this, by teaching us, that car- bonic acid gas is absorbed by leaves in the day time through their upper surface, and decomposed by them, its carbon be- ing added to the sap, and its oxigen emitted by the under surface. In the dark, leaves are found to absorb oxigen. Let us apply all this to the germination of seeds. The ox- Chemical pro- igen, known, as I have already said, to be necessary to this ^t- in gerna" process, being conveyed to the seed in its dark subterrane- ous situation, is absorbed by its cotyledons, already stored, from the constitution of the parent plant during their for- mation, with albuminous matter abounding with the carbo- nic principle. The chemical action of the oxigen on this albuminous substance renders the latter a more or less sac- charine, and, with the addition of the imbibed moisture, a milky fluid, fit to be transmitted, through the returning ves- sels of the cotyledons, into the stem of the embryo, espe- cially as all these important parts have already begun to swell by the absorption of moisture assisted by warmth. Hence we Light hurtful see why light is found hurtful to incipient germination, and t"lucipie.at why carbonic acid gas may be given out by seeds at that pe- riod. We perceive also why the outside of seeds is so com- monly dark coloured, or even black, as in canna, afzelia, and others, it being the only part of the vegetable body, as far as I recollect, that is ever positively black, except per- haps rftt THE STRUCTURE OF SEEDS. h'rips the skins of some fruits. It is, moreover, evident, rttat all the indispensable functions of the cotyledons are best performed under ground, and that when they rise into the air and light, it is not till after their primary destination is fulfilled, and then because, being fundamentally of the nature of leaves, they are also capable, in most instances, of assuming their functions with respect to light, ft is highly worthy of notice, that, in consequence of the original position of the cotyledons in all seeds, the oxigen gas must always be imbibed by their under side, that very same part which in leaves gives out this kind of gas during the day, and probably absorbs it during the night. It would have evinced a strange contrariety in the constitutions of two or- gans otherwise so analogous, I mean the leaves and cotyle- dons, if the upper surface of the latter, while in the unex- panded seed, had been presented to receive the oxigen gas. Stalk of the Where there is a separate albumen, without any pcrccp- embryo may tible cotyledons, it is probable that the stalk of the embryo perform the , function of a may* answer the necessary purpose; just as the stems of cotyledon, leafless plants must be presumed to perform the usual chc- ter is wanting. mical functions of leaves, though we cannot ascertain in what direction the different airs are imbibed or discharged, there being no decided upper or under surface in such stems, any more than in crisiform leaves. Such, however, are rare exceptions, which if not, as yet, found to throw any new light on the subject, certainly do not overturn any im- portant part of the above hypothesis. That some part, im- mediately connected with the embryo, must be stimulated in order to excite the germination of a seed, this phamomcrion being dependent on the vital principle, is evident. I con- ceive that, when present, the cotyledon or cotyledons are themselves simulated by the oxigen gas, or rather by the heat which chemists inform us is produced by the absorption of this gas, so as ib set their fluids in motion, and thus to ♦ pTopel the young root and rising plumula. Rut when the cotyledons are wanting, the embryo may very well be con- ceived capable of sufficient action, to imbibe for itself the juices of a distinct albumen, already become milky and sac- charine by the reception of oxigen and moisture; by which merely chemical process, as in barley, so considerable a de- gree OX Till . i?.iTGTUR:E OF SEEDS. 363 gree of heat is evolved, as must very powerfully exGite the vital principle of the budding vegetable. In the few cases where one or more cotyledons and a distinct albumen are to- gether present, it does not seem necessary, that the gas should act through the former upon the albumen, the two organs being but little connected, and its operation on the latter being independent of all vital or organic laws; but either the gas itself, or the heat produced, may very well so stimulate the vital principle of the cotyledons, as to propel their fluids into the embryo, and assist germination. This opinion is the more probable, as these Uuids must bo sup- posed more truly of the nature of sap, and more immedi- ately fit /or the use of the infant plant, than the liquor of the albumen. However this may be, the existence of a co- tyledon or cotyledons, together with a separate albumen, in seeds, seems to me so unusual, as not to occasion much difficulty, and I would define a cotyledon to be a vital or- Definitions of gan, capable, as such, of being stimulated by oxigen, heat, the cotyledon. or both, for the propulsion of its contents ; while such an albumen is merely a repository of nutritious vegetable mat- ter, subject to the laws of chemistry alone, and only pas- sively resigning those contents to the absorbing powers of the embryo, to which it is attached. I must now, under the impression of what has just been. Arrangement advanced, return to the arrangement of plants by their co- j^ t^nt^ tyledons. ledons. Plants in general are dicotyledonous, having a pair of these Those with organs, which commonly rise out of the ground ; but if they tw0 or more* do not, it appears;, from the consideration of the legumi- nous tribe, that such a difference could scarcely serve for a generic distinction, much less for that of a class or order. It also appears, that, if the number of cotyledons exceeds two, as in pinus and a fvw other instances, the difference is of little or no use for systematical purposes, and of no physiological importance whatever. The cotyledons of pi- nus all present their backs to receive the oxigen. Some plants appear to bo really furnished with one simple Morncctyl©. cotyledon, aszamia, and according to Gaertner's figures and descriptions, tlie true scitaminew, as amomum (ids zingiber), (ilpiiiid) &c3 while canna geema to have no potykdou, but * only S6i OS THE STRUCTURE OF SEEDS. only an albumen. Can this be true ? and if so, what is th* value of such a distinction in a natural classification ? The liliacecr, palmte, and now the orchidece, are acknowledged to be acotyledonous, having only an albumen ; while the grasses, so nearly allied to them, have one cotyledon, for I presume their scale must be admitted as such. Gaertner's phrase of embryo monocotyledoneus applied to these last- mentioned families may occasion a mistake, which would be avoided by the term embryo simplex, or indivisns, express- ing his idea of the simple figure appropriate to this part in such plants, but which does not prevent its upper extremity being strictly analogous to the plumula of the dicotyledones. - It seems to me therefore, that this learned writer is mistaken in saying the monocotyledonous plants never have any phi. mula. They have not indeed that feather-like configuration in the ascending point of their embryo, which gave rise to the name, but the organ so called is, and must be, present. To dispute about the terra is as little to the purpose as to contend, that the orchidece have no pollen, because it is not of a powdery appearance. ferns. From Mr. Lindsay's account of the germination of ferns in our 2d volume, this family must be deemed monocoty- ledonous. Their germination seems at first analogous to that of mosses, as given by Hedwig in his Theoria, but the numerous and branched cotyledons of the latter overset all analogy, and indeed all classification of plants by the num- ber of the parts in question. Nothing could be more unna- tural than to separate mosses for this reason from the other cryptogajnic vegetables, and therefore Jussieu can scarcely believe these parts to be cotyledons ; yet it is not possible to call them any thing else, and to suppose them a peculiar, and hitherto unheard of organ, would but increase the dif- ficulty. Gaertner in the Introduction to his great work, Fuci. V- 157, tells us he has seen many cotyledons in several fuel also, and that he suspects others of the more imperfect plants, hitherto referred to the monocotyledones, may be si- milarly circumstanced. It seems that too much, by far, has been taken for granted in this department, though the parts under consideration form the great hinge upon which all na- tural sys ems turn. It is only by analogy, that the great family, ON THE STRUCTURE OF SEEDS. 365 family, or natural order, of lichenes has been judged mo- Lichens, nocotyledonous, an analogy which the fuci, if Gaertner be correct, render very doubtful. The germination of the Fungi. fungi is at least equally uncertain. I mean not however by any means to invalidate the im- Cultivators of portance of the distinction between such plants as have two (iiv!delheir or more cotyledons, and such as have only one or none, tasks, and assist however inaccurate the terms commonly used to distinguish ^ho'ut rival-- them may be. Much less am I inclined to throw any need- ship, less impediments in the way of those, who labour at the arduous and important study of natural classification, or to detract from the well-earned fame of such men as Gaertner and Jussieu, on account of difficulties and imperfections unavoidable in so abstruse a study. No real friend to truth and knowledge ever foments invidious rivalships in philoso- phy. The field of science is now so vast, that its different cultivators find the advantage of dividing their tasks, and thus the students of physiology, of natural systems, and of artificial ones, may all powerfully assist each other. Truth, is pursued by different paths, and nothing is more pleasing than to see the various observers of Nature, in a Society like ours, mutually and harmoniously contributing, as we have all along done, to enrich the scientific hive. I would therefore conclude by recommending those, who have lei- sure and opportunity for the purpose, to observe for them- , selves the germination of the principal families of plants, not only of such genera as are in dispute, but of all about which there can be any doubt, most of which will easily be indicated by a comparison of Gartner's work with the re- marks in the foregoing pages. Norwich, Nov.Z, 1807. XI. Observations 366 ON GUTTA GAMBEER. XI. Observations on Nauclea Gambir, the Plant producing the Drug called Gutta Gumbecr, zoilJi Characters of tzco other Species. By William Hunter, Esq. Secretary to the Asiatic Society. Communicated by the President *. Gutta gambeer JLT has been a question, among naturalists and writers on produced from t^ materia medica, whether the little cakes or lozenges a species 01 ' ° nauclea. called gutta gambeer be prepared from the mimosa catechu^ or the produce of a different plant +. This question, if not already determined, 'I am enabled to resolve by actual observation, having seen the substance made from a species of nauclea^ of which I beg leave to offer the following de- scription. Characters of the nauclea gaiabir. Nauclea Gambir. Funis uncatus. Daun Gatta Gambir, Rumpk. Arab. t. 5, 63, t. 34, /- 2. Climbing. Branches round. Leaves ovate, pointed, smooth. Stipules two, lateral, caducous. Peduncles axillary, solitary, simple, jointed. Stem shrubby, twining to a great height, covered with a rough brown bark. Branches crowded, round, smooth; branchlets opposite, widely spreading. Leaves opposite, petiolared, ovate, pointed, waving, widely spreading, smooth, below marked with trans- verse parallel veins. Stipules at the bases of the branchlets and petioles, two, lateral, parabolical, sessile, widely spreading, smooth, caducous. Peduncles axillary, solitary, round, straight, horizontal, much shorter than the leaves; jointed near the apex and bracteat- d : after the flowers have fallen, the lower joint persistent, recurved, forming a hooked spine. * Trans, of the Linnean Soc. vol. IX, p. 218. f Murray, Appar. Med. vol. II, p. 54i>. Bracteas ON QUTTA GAMBEER. gg7 Bracteas four, ovate, acute, spreading very small, cadu- cous. Flowers aggregate, globular ; composed of very numerous florets, crowded on a globular, uaked, very small re- ceptacle. .Cja.l. Pcrianthium common, none. Proper, one-leafed, oblong, incrusjing thcgcrmcn, per- sistent ; mouth five-cleft, divisions lanceolate, erect. Cox. as in the Genus. Stam. Filaments five, very short. Anthers oblong. Capsule stalked, oblong, incrusted and crowned with the calyx; tapering to a point below; two-celled, two- valvcd; the valves adhering at the apex, splitting at J.he skies. Seeds very numerous, oblong, very small, compressed, furnished at both ends with a membranous pappus. The flowers, when fully spread, I suppose last a very short time; for although I have frequently looked for them, 1 was never able to find them, whence I have been obliged to omit the description of the pistil. From the leaves of this shrub is prepared the substance Method of pre- called gutta gambeer, in two ways. The first is by boiling [5a™,g £he gut* the leaves *. This process was performed under my inspec- tion, by a Chinese, at Prince of Wales's Island. Seven catties (or9ylbs.) of the leaves, plucked clean from the stalks, were boiled in a large pot for one hour and a half, adding more water as the first wasted, till towards the end of the process, when it was inspissated to the consistence of a very thin sirup. When taken oft* the fire, and al- lowed to cool, it became solid. It was then cut into little squares, which were dried in the sun, turning them fre- quently. After one month, I weighed them, and found tea ounces and two drachms, troy weight. The gambecr, prepared according to this process, is of a Another mode brown colour ; but from some parts of the Malay coast, and of PreParing »*• of Sumatra, it is brought in little round cakes almost per- * See Marsden's Sumatra, p. 243, — where he quotes, for a par- ticular account of the manufacture, the second volume of tha Transactions of the Batavian Society. fectlv \ 368 ON GUTTA GAMBEEfc. feclly white. According to Dr. Campbell of Bencoole?i, this is made by cutting small the leaves and young twigs, and infusing them in water for some hours, when a faccula is deposited, which is inspissated by the heat of the sun, and moulded into round cakes. Its qualities '^ie gambeer, when first tasted, impresses on tho palate a and use. strong sensation of bitterness and astringency. But it af- terward leaves a sweetish taste, which remains a long time. From these sensible qualities, it might reasonably be ex- pected to prove useful in medicine. And accordingly, we are told that it has been found beneficial in angina and aph- 'thae, as well as in diarrhoea and dysentery. The drug was infused in water, to which itgave the colour of the infusion of bohea tea*. By the Malays it is mixed with lime, and applied externally to cuts, burns, boils, &c. Chewed. But tne most frequent use of it is to chew, along with the leaves of betel, in the same manner as the hut (or catechu) in other parts of India. „ , . For this purpose the finest and whitest kind is selected. ning and dye- The red, being strong tasted and rank, is exported to China in8- and Batavia, where it is used for Uiq purposes of tanning and dyeing. For the first of these uses we might suppose, from its sensible qualities, that it is well calculated; and p. , . . some rough experiments, which I hive made on it with ani- mal gluten, compared with those of Dr. Roxburgh on kut, evince.it to be richer in tannin than that substance. Differences ^ne cme^ places of manufacture are Malacca, Siak and Rhio; and the process of boiling is most generally prac- tised ; insomuch that the generality of manufacturers there are ignorant of there being any other. The colour and other qualities, they allege, depend on the vessel and the skill or attention of the operator. Thus an old manufac. turer, with Chinese iron pots, will produce a whitish drug; whereas with a Malay iron pot its colour will be browner. The first cuttings also yield a whiter drug than the subse- quent ones. » Murray, 1. c. Seba. item. Buisson apud Degner. de Dysent. p. 21)7. For ON GUTTA GAMBEER. 369 For the cultivation of this plant a rich red soil is prefer- Culture. red. It gives the most luxuriant crop when the rains are frequent, but does not thrive in grounds that are apt to be flooded. On this account the side of a hill is esteemed bet- ter than any other situation. The plants are propagated from seed. In three months after sowing, they appear above the ground ; after this they grow fast, and may be moved to the field when nine inches high. They are there planted at the distance of eight or nine feet, so that one orlong (of eighty yards square) con- tains about seven hundred plants. At the end of one year Crop*, from the time when they are planted in the field, a small crop of the leaves is obtained. A larger is got in eighteen months ; and the third at the end of two years, when the bushes have attained their full growth. They continue in their prime, and admit of being cut' twice a year, during a period of twenty or thirty years, provided care be taken to keep the ground clean and the roots free from weeds. Their tops must be cut so as to prevent them from growing to a greater height than five or six feet. From good ground and a garden well kept, ten peculs Produce, (of 133-jlbs. each) of dry gambeer are usually obtained on every orlong twice a year, or twenty peculs per annum. As it is cut every six months, and should then be boiled off, the leaves ought to be of the same age ; but, from a want of means, it often happens, that the year is nearly expired before the cutting is done, which should have been made at the end of six months. In this case the young leaves yield a whiter drug than the old. As to the quantity afforded by each, in proportion to the weight of leaves, I have re- ceived contradictory information, so that I conclude little attention has been paid to this circumstance. The price of the drug, at Prince of Wales's Island, va- Price, ries from four to eight Spanish dollars per pecul. The finest and whitest kind is that formed into little round cakes or lo- zenges. It is sold by tale, at three dollars and a half for the laxa (or 10,000), and one laxa weighs about 40 catties. This gives 8£ dollars for a pecul. The price of sago at Prince of Wales's Island is generally Adulterated about three dollars per pecul. Hence the manufacturer is *lthsaS°- Vol. XXII.— Supplement. 2 B often 370 os THE variegation or PLANTS. often tempted to adulterate his gambcer with this article, which mixes intimately, but may be detected by solution in water. XII. On the Variegation of Plants. In a Letter to Richard Anthony Salisbury, Esq. F. R.S. and L.S. by Thomas Andrew Knight, Esq. F. R.S. and L.S,* My dear Sir, Variegated 1 HOUGH variegated plants have long occupied the caro p yy1?*?*" ana* attention of the gardener, it does not appear, that the naturalists. peculiarities which distinguish them have much attracted the attention of the naturalist; and lam not acquainted with any experiments, which have been made either to discover the cause of variegation, or the effects produced by it. I am therefore induced to trouble you with an account of a few experiments, .that I have made on one species of vari- 1 egated plant, from which I obtained an unexpected and somewhat interesting result. The va Ugatcd There is a land of variegated vine, well known to gar- Tifle- Jcticrs, (the Aleppo), which affords variegated leaves and fruit; and as the grape, though small, possesses a very high flavour, and much richness, I wished to obtain some offspring cither from its seeds or farina, with the hope of piocuring berries of larger size, and at the same time of I m taming whether its variegation would be transferred to tie offspring. Other* imr>reg- "With this object in view I extracted the immature stamina rated with its Q^ the blossoms of the white chasselas, and white frontig- farina became * 7 . . ° TAriegatcd. nacvmeif: and at the proper subsequent period I intro- duced the farina of the Aleppo vine: from this experiment 1 obtained, in the succeeding spring, many seedling plants. These plants, which were raised in a hot-bed, presented no singularity of character on their first appearance ; but early in the succeeding summer I had the pleasure to observe * Trims, of the Linnean Soc. vol. IX, p. 26*8. purpl« ON THE VARIEGATION OF PLANTS. 371 pttrple stripes in the seed-leaves of several of them ; and in the autumn the leaves of many were variegated. I did not however obtain a single plant, which promised to produce, er has subsequently afforded, either coloured fruit, or co- loured leaves, free from variegation. When, on the contrary, I have introduced the farina of Farina of black a black, or purple grape into the blossom of a white one, render white none of the plants I obtained have ever been variegated ; ones variegated. and the colour of the leaves and fruit, which these in the first year afforded, indicated with certainty the colour of all the produce of such varieties, in whatever soil cuttings taken from them were subsequently planted. But in the variegated vines the result has been wholly dif- In variegated ferent; and though the leaves and fruit first produced by JjgJ^J® effeC* some of them contained more tingeing matter than any of the coloured kinds, they subsequently produced, even on the same tree, some bunches almost entirely black, others perfectly white, others lead-coloured with stripes of white, and others white with minute black stripes ; and grapes of all the preceding colours are very frequently seen on the same cluster. The leaves are also subject to the same vari- ations, and the colours in them are in some instances con- fined to the trpper, in others to the under surface, and sometimes extend quite through ; and both the leaves and fruit of some of the branches have become permanently colourless. It appears therefore obvious, that the tingeing matter of Their colouring variegated grapes, though probably not essentially different matter com- from that of others, is differently combined, and united toculiarway. the plant ; and as the variegated grape afforded offspring si- milar to itself, and none similar to other vines, which per- manently afford coloured fruit, it may be confidently infer- red, that the nature of the union between the tingeing mat- ter and the plants is very essentially different. All the variegated plants, that I obtained from the farina The variegated of the Aleppo vine, are not only perfectly free from anTvLoTous, disease and debility of every kind, but many of them pos-and therefore sess a more than ordinary degree of hardiness and vigour : debdkvT8 ^ and two of them appear much more capable of affording -mature fruity in the climate of Englaad; than any now 2 B | cultivated. 3?2 ON TUB VARIEGATION OF PLANTS. cultivated. It is therefore sufficiently evident, that th« kind of variegation which I have described is neither the offspring oil', nor counectcd with, disease or debility of any .kind. Variegated But the same inference must not be drawn respecting *fe' other variegated plants; for variegation itself appears to consist of several distinct kinds. The leaves of a variety * of the common cabbage are often seen, in the cottage garden, curiously tinged with different shades of red and purple; like the leaves of the vines which I have described : but in the cabbage these colours combine and melt into each other, whereas in the vines the distinct colours are separat- ed by well defined lines. The colours of the cabbage are trat:: fcrred to its offspring, which is perfectly hardy and vigorous. Shotted lettuce. Xfc$ spotted lettuce must also be classed with variegated plants, and the offspring of this is as hardy as those of other varieties : but the most common kind of variegation, Leaves striped i" which the leaves are variously striped with white and Trith white and yeiIo\% , though not the offspring, as some writers have patently con- imagined, of disease, is, howrever, closely connected with oected with some degree of debility ; possibly owing to the imperfect action of li^ht on all such parts of the leaves as are cither white or yellow. For I have observed, that variegated hollies are less patient of shade, than such as are wholly green ; and I have never seen any plants, the leaves of which are wholly white or yellow, that continued to live wholly beyond a single season. A variegated plant of the rasp. ^:ute oryrUowbvj.j.y^ which sprang from seed in my garden, became wholly white in the third year ; but it perished in the suc- ceeding winter, and I should be disposed to conclude, that .plants the leaves of which are entirely white or yellow, cannot long survive; but that du Hamel* has described a variety of the peach tree, of which he says, u son bois, ses feuilles, ses ileurs, et son fruit, tant extirieurement qu'interiurement, sont tout a fait blancs." This variety is at present, I believe, wholly unknown to our gardeners; and I suspect, that it was always a debilitated plant, and that it in consequence exists no more. I am, &c. THOMAS ANDREW KNIGHT. * In.his rI reatise on Trees.— Art.iclt Peach Tree. XIII. Method IMPROVED METHOD OP PAINTING CANVAS. ,fc>' , .) XIII. Method of painting Linen Cloth xcith Oil Colours, be more pliant, durable, and longer impervious, to Water, than in the usual Mode. By Mr. William Anderson, of his Majesty s Dockyard, Portsmouth *. SIR, J. BEG leave to lay before the Society of Arts &c. the following improvements and observations, which I hope will be of service to the public. Having never heard or read of any method being disco- p^nt m canvag vered to prevent paint when laid on canvas from harden- hardens and ing to such a degree as to crack and eventually to break the canvas, and render it unserviceable in a short time; and having been an eye-witness for many years of much canvas perishing for want of such discovery in the immense quan- tities painted for covering seamen's hammocks, and for other uses on board his majesty's ships ; I long had it under con- Ingredient ta sideration to find out such an ingredient as, when mixed Prevent this . i i. -i i ..discovered. with paint, would preserve the canvas and paint laid thereon from the damages above mentioned, and after experiments for a considerable time, I have discovered such au article, and made trial of it with effect above three years. The canvas I have painted has been submitted to the in- spection of the Navy Board, who are so perfectly satisfied with my new method, that general directions are now given to paint all canvas in his majesty's dock-yards in this manner; which, in addition to the advantages I have before mentioned, actually saves an expense of one guinea in every Saves expense. hundred square yards of canvas so painted, as I have fully stated to them. The ingredient I use is not only scr- Answers for viceable for ship's canvas, but also for canvas designed for Pa,n,i,1?s, floor , . . cloths, &c. paintings, for floor cloths, and for painted coverings within and without doors. I have no doubt of it being applied to many other purposes I am yet unacquainted with ; as from • * Trans, of the Society of Arts, vol. xxvi, p. 136. The silver medal of the Society was voted to Mr. Anderson for this invention. actual 374 IMPROVED METHOD OF PAINTING CANVAS. actual trials of near four years, I can vouch for its being a preserves pa'mt preservative to red, yellow, and black paints, when ground in casks for jn 0|j an(j pU£ jn casts% When the paints were examined at the expiration of such time, they discovered no improper hardness ; but when laid on the work with a brush, they dried in a remarkable manner, without addition of any of the usual drying articles. I still preserve some of these paints for future trials, and I believe this plan of preserving colours will be of essential use to colourmen, and other persons who purchase colours for exportation. The ingre- dient I use is perfectly simple, being a solution of yellow soap ; and the composition for painting is made in the fol- lowing maimer : The composi- To one pound of soap I add six pints of water in a vessel **°a' over the lire ; in a few minutes after the boiling of the water the soap will dissolve ; while hot it is to be mixed with oil paint, prepared as hereafter directed, and is then fit for im- mediate use. The above quantity of soap solution will be sufficient to mix with one hundred weight of paint. The first coat to be laid upon the canvas is to be intirely of this composition, without first wetting the canvas in the usual way. A very small proportion of it, or none, is necessary in the second coat : and the third coat should be of oil paint alone. Old method of The method heretofore practised in his majesty's dock, painting canvas var(js fQT paiatiag canvas, was as follows: The canvas was first wet with water, then primed with Spanish brown; a second coat given it of a chocolate colour, made from Spanish brown and black paint; and, lastly, finished with black. This mode is destructive, and more expensive than mine, in the proportion before mentioned. >7ew method. ^n m,V method, to ninety-six pounds of English ochre ground in boiled oil, I add sixteen pounds of black paint, being one sixth in proportion of the ochre ; this, when mixed, forms an indifferent black. The solution, made of one pound of soap and six pints of water, is to be added to this paint, and well united therewith ; and without the canvas being previously wet, this composition is to be laid upon the canvas, as stiff as can conveniently be done with the brush, and this first coat will form a tolerably smooth surface* IMPROVED METHOD OF TAINTING CANVAS. 375 surface. The second coat is to be formed of the same pro. portion of English ochre and black, without any soap so- lution ; and the third or finishing coat, to be done with black paint as usual. I am, Sir, Your obedient humble Servant, W. ANDERSON. Master Painter of H. M. Dock Yard, at Portsmouth. Port sea, Oct. 31st, 1806. SIR, AGREEABLY to the request in your letter, I have en- Thecolourmay closed certificates relative to my new method of Paintingfro^b^ne^i,u. canvas ; and I take the liberty of informing you of a ed canvas, method of obtaining from painted canvas, unserviceable, the whole of the colour laid thereon, and to do it at a very small expense. This I discovered since I last wrote to you, and I believe it will be of considerable advantage to govern- ment, who, for want of such a thought, have buried and burnt immense quantities of ships' hammock cloths, when found unserviceable, to prevent embezzlement from taking place. I suggested the idea to N. Diddems Esq. builder of Portsmouth yard, who communicated it to the honourable George Grey, Commissioner. I obtained leave to make an experiment, which I repeated thrice, and found that from one ton of painted canvas, unserviceable, I obtained, upon an average, four hundred weight of dry colour, in at a trifling ex- value to government nine pounds six shillings ; the expense by^icination. of the process not exceeding six shillings. This I effected by calcination, raking aside the ashes and sprinkling them with water, to prevent loss of paint through excess of heat. By passing the calcined matter through a fine sicvo, it is perfectly prepared for grinding; it grinds well, possesses a good body for covering with, and dries well with a good gloss. Its increase of bulk, in compari- son with common colour of equal weight, gives it the ad- vantage of covering more work. The colours yielded by the calculation of different coloured canvas are as follows, 4 w. 376 IMPROVED METHOD OF PAfNTING CANVAS. viz. Canvas which has been painted with black paint only, produces a black colour. Canvas finished black, but which has had a previous red or yellow ground, will produce a dark chocolate colour. Canvas painted lead colour, will yield a good dark lead colour. I am, Sir, Your obedient humble Servant, W. ANDERSON. Testimonies to Certificates, dated March, 1807, were received from the the superiority following persons, viz. of canvas paint- . c i» ed in the new A* atow, lieutenant and commander of the gun brig mode, Steady, stating, that in the preceding month of October he had received on board his ship a set of hammock, cloths, painted after the method invented by Mr. William Ander- son, which had been constantly in use since the time above mentioned, and appeared fully to answer the end proposed, of rendering the canvas soft and pliable, and of preventing its cracking, or the paint peeling off, which in the old method had been a subject of much complaint. Johp Pridy, lieutenant and commander of the Gla- diator, and formerly commander of the Dapper, on which latter ship a set of hammock cloths, painted after Mr. Anderson's method, appeared fully to answer the end pro- posed. P. F. Wyatt, oil and colourman, Portsca, stating, that he had seen canvas painted after Mr. Anderson's new method, which, after a trial of sixteen months, remained perfectly soft and pliable, the paint by no means crackmg or peeling off, and that the gloss was retained, though it had been exposed to all weathers. He farther added, that and to the he had seen the paint prepared by him from old painted ofTaint from* canvas found unserviceable, and had worked and painted •Id canvas. therewith ; that it was, in his judgment, very good, and would answer either on canvas, wood, or iron. i\Ts. .Diddcms, master shipwright, Portsmouth, dock- yard, stating that Mr. Anderson had proposed to him to obtain, by calcination, from old unserviceable painted, canvas, the paint which had been laid thereon • that such - experiment IMPROVED METHOD OF PAINTING CANVAS. 377 experiment was made, and four hundred weight of dry serviceable paint prepared from one ton of such canvas ; that he had seen it when ground in oil and laid on work, when it appeared to possess all the properties of good paint, and had therefore been recommended by him to the Navy Board. SIR, IN answer to your letter of the 25th of April, in which Samples sent t^ you informed me, that the committee were desirous that I the Society, should furnish them with a sample of canvas painted in the old method, and another on my improved plan, I trust that I shall be able fully to comply with their requests. In the first place, I have sent a small sample of the residuum of the burnt canvas, fit for grinding in oil for paint, also a piece of canvas painted therewith, marked No. I ; another piece painted after the old method, marked No. 2 ; another piece painted according to my process, marked No. 3 ; and, lastly, a piece finished intirely with the new composi- tion, marked No. 4 ; each sample having received three coats of paint. Upon examining No. 2, you will find it becoming from time to time more stubborn, in conse- quence of the paint hardening; and when a small ridge is formed in it, by pressing it between the finger and thumb, it will soon discover, that it is subject to crack, and by this means permitting the wet to enter it, will soon rot the canvas. The space of time proper between laying on the new Time between preparation and the second coat ought to be one entire1 e coats" day ; but if saving time is an object, the second coat may be put on the day following the first ; for if the canvas is placed in an advantageous situation for drying, the compo- sition will dry or harden so as not to rub off. Canvas finished intirely with the composition, leaving it The canvas to dry one day between each coat, will not stick together if J2J£* Stlck laid in quantities, as you will find by making experiments on the sample No. 4. Since the Navy board have given directions for ships' Requires liute canvas to be painted according to my new method, I find, tline to fnuslu upon calculation, that 1 have painted upwards of twenty thousand yards since November last, a great part of which has 378 IMPROVED METHOD 01" PAINTING CANVAS. has not been hung up for painting and drying more thaa one week, as no more time could be allowed me, in conse- quence of ships sailing. My plan was therefore to lay on the composition the first day, to coat it the second day, and leaving one intermediate day, to finish it on the fourth. Three days were then allowed it to dry and harden, and when afterward taken down and folded together in cloths, containing sixty or seventy yards, they did not stick to- gether. Saving of three Having no means of giving information to persons con- labo^i lhC ccrned m grinding colours, so well as through the medium colour-grind- of the Society of Arts &c, I beg leave farther to relate how "¥• I have, for the last three years, saved the labour of three men out of four in grinding colours with the common mills employed for this purpose. One mill has ever been con- sidered sufficient for a man to turn, whereas one man can now, with perfect ease, turn four mills ; this is effected by placing two mills on each side of the winch, so close as only to leave room for the fly wheel to play between thera. The spindles of each on either side are locked together by a small iron collar, with a pin passing through it. The distance of the mills thus paired from each, in order for the man's standing between them to turn, is two feet six inches. The distance of the arms of the winch screwed ou the end of the spindles on either side is two feet two inches ; the length of the arm is one foot six inches from the spindles to the bar across which the man clasps in order to turn. Fly wheels. Fly wheels at the extremity are impediments. Necessity was truly the mother of invention to me in this case, as I had great demand for paint, and I was not allowed men sufficient for the work in jthe common way. Persons will scarcely believe,- without seeing the expe- riment, the ease with which they turn. If a little ex- traordinary motion is first given them, and they are then left alone, they will continue to go round sixteen times; so that a man with one hand may turn them. I am, Sir, Your obedient humble Servant, Wm. ANDERSON. SIR, IMPROVED METHOD OF PAINTING* CANVAS. g*}^ SIR, I HAVE stated to the Admiralty Board the several im- Testimony to provements made by me in paint work, and in consequence the superiority thereof they have desired the principal officers of our yard canvas. to report to them on their merits. The officers, who have for more than twelve months past daily had the execu- tion of them under their inspection, have recommended the same in stronger terms, and the advantages thereof, to the lords commissioners, beyond my statement. I have in- closed to you a certificate relative to the ship Hibernia, which arrived here the 12th of May last, and for which vessel I painted a set of hammock cloths, containing thir- teen hundred yards of canvas, in June 1806, after my new method. I am, Sir, Your obedient humble Servant, Wm. ANDERSON. Portsmouth, Nov. 27, 1807. The foregoing letter was accompanied with a certificate from Captain Hicks, and William Trounsell, carpenter of his majesty's ship Hibernia, stating, that the hammock cloths on board the said vessel were painted in June 1806, after Mr. William Anderson's method; that they were pliable, and did not crack, nor the paint peel off, and were, in their opinion, preferable to those painted in the common way. SIR, I BEG leave to trouble you with a farther certificate re- lative to my method of painting canvas. I have also discovered a lead coloured paint, highly ad- vantageous for all iron-work exposed to the weather, and preferable to that commonly made from white lead and black. The preparation is as follows : Process for Lead Coloured Paint on Iron. I take a fire shovel, and put a small quantity of com- l^ad coloured mon litharge thereon, and place it over the fire. I then pauu for uon* take a small portion of flour of brimstone between my fingers, and scatter it over the litharge, when the same is sufficiently UA> IMPROVED METHOD OF PAINTING «ANVAS. durability of the painted canvas. sufficiently warm to give light to it. It is instantly con- verted to a blackish colour, which, when ground in oil, makes a good dark lead colour. It dries quick, gets remarkably hard, and resists the weather beyond any other lead colour. It will be extremely useful in the Ordnanca department for, painting guns. I am, Sir, Your humble Servant, Wm. ANDERSON. This letter was accompanied with a certificate from J. B. Harrison, lieutenant and commander of his majesty's brig Red-Breast, dated Feb. 26, 1808, stating, that the hammock cloths on board the said vessel were painted by Mr. Anderson, in April 1807, and had since that time been constantly in wear, and exposed to the weather day and night; that owing to this new mode they had been preserved supple, without cracking, and that the paint ad- hered to them in a far superior manner to the former mode of painting. State of the botanical garden at St. Vincent. XIV. Account of the Royal Botanical Garden in the Island of St. Vincent. By Dr. Alexander Anderson. * SIR, FlU ,OAI my long silence you will conceive me either neg- lectful or ungrateful to the Society, but this is not the case. The reason is, I had nothing of consequence to mention relative to the garden, and it would be trespassing on your time, and interfering with matters of consequence by troubling you with trifles. Although I have introduced a number of plants in the course of last year from different quarters, yet few of them are yet known to possess valuable properties, except some useful woods. Trans, of the Society of Arts, vol. xxv, p. 187. I am, BOTANICAL GARDEN AT ST. VINCENT. J81 I am grieved to inform you, that I have lost one of my nutmeg trees ; unfortunately the other, which prospers luxuriantly, turns out to be a male plant, consequently worth nothing. I blame myself in some measure, for this loss, by taking too much care of it, and not letting nature take her own way. Unluckily the war precludes any cor- respondence with Cayenne, or I would have replaced it i from thence. The same cause has cut off all supplies from other parts. Through the medium of a gentleman who was here last year from Cuba, I expected to have had, before now, some of the productions of Mexico and adjacent parts of the continent, particularly myroxylon, or balsam of Peru ; however, if I do not procure it through that channel, I have found out another from whence I have hopes. The Gomertur palm, which produces the material for Gomertur cordage in the East Indies, is thriving here surprisingly, p * and, I think, might be rendered a valuable production to these islands. The mode of its producing the fibrous web, and the guard or protection surrounding, clearly point out, that nature intended it for the use of man ; one tree pro- duces an astonishing quantity. I think the fibres from the plants in this garden are stronger than the specimens I have seen from the East Indies. A small piece of the web, with its protector, I now transmit you. I have great reason to Only the sugar think that but few plants have been raised by the planters can(; attended in the different islands, from the large quantities of seeds planter*. I have dispersed amongst them. The fact is, that no attention, except by a few individuals, is paid to any other plant but the sugar cane, and no other is in estimation with them. The bread-fruit, although one of the most valuable pro- Tliey even dis ductions yet sent them, is neglected and despised, unless by 'lk? the bread a few persons. They say that negroes do not like it, and will not eat it, if they can get any thing else ; but this is not really the case, as I know, and can declare from experience, that the very reverse is the fact, when once they are a little accustomed to it. The fact is, that the planters hate giving it a place on their estates, as they regard it as an intruder on their cane land, and they dislike any other - object 382 BOTANICAL GARDEN AT ST. VINCENT. and are in object but canes. As to futurity, they think nothing %f neglfeenfof what may be the wants of themselves or negroes three or future benefit, four years hence. Even their most valuable mill-timber, than which nothing is more daily wanted by them, they are constantly destroying instead of preserving. They import it at an exorbitant rate, and the importation is precarious. With proper economy and management, there are few necessaries for themselves or negroes, but which might be raised on their own estates, instead of importing them from America, unless it be lumber, and, probably even that might be done in time in the back, cool, and mountain- ous situations. I am trying what may be done from the pine tribe. Cinnamon. I am happy that many are now paying some attention to the cinnamon, as the demands on me for the plants are frequent, which I. impute to the specimens of it which I have shown. , ^Iack pepper. The black-pepper plants have not yet produced ; I have them in plenty, and am trying them in various situations, and can easily increase them by cuttings ; unluckily I can procure no information as to their culture in the East In- dies, or of the soil or situation in which they thrive best. Cloves. I send you some more cloves, the last year's produce of two small trees ; next year I expect from several others : you will also find inclosed a lump of gum resin from cochola ©dorata. As it issues in large quantities from wounds in the bark, it might be procured in plenty from Trinidad, if found useful. Trees of it, of enormous size, are abundant there. Other specimens of terra japonica would have been sent with some other articles, if all my attention had not been engrossed about the late addition to the garden : the same cause has prevented rae from excursions to other islands for larger supplies of plants. I remain, with most sincere regard. v Sir, Your obliged and obedient Servant, ALEXANDER ANDERSON. SIR, BOTANICAL GARDEN AT ST. VINCENT. 33J SIR, SINCE your last letter to mc very little matter interesting Correspond- to the Society has occurred, and few acquisitions made to c™e i'literruPt- v., . .. . ,._ edby the war. the garden subservient to medicine or commerce. War interrupts correspondence in natural history as much as speculations in commerce. For 18 months past I have had expectations of some use- ful plants from Mexico, aad other Spanish colonies in that quarter, by the way of Cuba, but thence the transportation must be circuitous by North America, and after that sub- jected to loss and interruption, before they can reach St. Vincent. I have therefore given up all hopes while the war continues. As the Society may be desirous to know the present Catalogue of state of the garden, I have transmitted a catalogue of the Plants* variety of plants it contained on tlje 24th of September last : there are many more from different quarters received with- out names, or those that are known by the aborigines, and I cannot arrange them until they flower, t am, with great respect, SIR, Your most obedient humble Servant, ALEXANDER ANDERSON. The catalogue alluded to, which is dated September 24, 1806, enumerates G7 commercial and medicinal plants ; 49 esculent; 101 medicinal ; and 63 economical: 76 valuable woods; 88 fruits; and 929 curious or ornamental exotics. There are likewise many others, which, not having flow- ered in the garden, cannot be ascertained. XV. Query on Accidents frequently happening to Dies with i&hich Medals are struck. In a Letter from a Correspondent. To Mr. NICHOLSON. SIR. iCEADING the life of Rambcrt Dumarest in a French pe- riodical publication, I was struck with the following remark. "To 384 Dies of medals ▼ery liable to be broken. Are there any mefms of pre- senting this ? QUERY ON THE BREAKING OF DIES, U To the specimens of Mr. Dumarest's talents I ought to add the medal on the peace of Amiens, the execution of which was awarded to him after a public competition. Un- happily, we arc informed, one of the dies was crushed under the mill. This is a very frequent accident, and dis- couraging to the artist. Dumarest experienced it in a very vexatious manner ; he was obliged to make almost every die he executed over again, and for one of his medals this happened no less than eight times following. The causes of it deserve inquiry. No doubt they depend on the quality of the steel, the care with which it has been forged, its temper, and the influence of the atmosphere; but still more on the mills, and the care taken in coining." As I cannot gain any instructions on this point from the books I have at hand, and have no opportunity of acquiring information from any artist, I should be happy to be in, formed through the medium of your Journal, whether there be not means of preventing this. It appears, that Dumarest was in England sometime, and employed in the manufactory at Soho by Mr. Bolton, so that he must probably have been acquainted with many pre- cautions taken there against an accident, to w hicjj it might be supposed the dies would be particularly liable, under the pressure of Mr. Bolton's powerful machinery. I am, Sir, Your very obedient humble Servant. C. 0. T. French tran«- lat'on of Ar- chimedes. „V C I EN T I F 1 C N E JVS. IT is somewhat remarkable, that the works of a mathe- matician so justly celebrated as Archimedes has never been translated into any modem language till lately. I believe his Arenarius is the only tract we have of his in English ; but I am informed a French translation of the whole of his works, that have reached us, has lately been published at Paris. INDEX. Abscission, a mode of propagating fruit trees, 322 Acid, carbonic, method of impregnat- ing water with it, ' 139 Acids, their use in gravelly com- plaints, 50 Ackermann, Professor, on cretinism, 295, 299 Acton, Mr. observations on his analysis of the fossil called Thunder-pick, 69 Addition table, on a new plan, 262 Aikin, Dr. 233 Aikin, Mr. A. on the composition of the salts of batytes, 301 Air changed by respiration, 180 Albumen of vegetables, 355 Alburnum of trees, origin and office of, 27 Alkalies, how far beneficial in relieving arthritic pains, 48, 50, 53 Allen, W. Esq. on the changes pro- duced by atmospheric air and oxigen gas, by respiration, 180 Amalgum produced from ammonia, 54 Analysis of human calculi, 36— Of cal- culi from other animals, 43 — Of the anthophyllite of Norway, 76— *Of a mineral water in Worcestershire, 267 —Of barytic salts, 301— Of James's powders, 316 Anderson, C. Esq. 79 Anderson, Mr. W. his method of paint- ing linen cloth with oil colours, so as to be more pliant, durable, and longer impervious to water, than in the usual mode, 373 Anderson, Dr. A. his account of the royal botanical garden in the island of St. Vincent's, 380 Animal matter in fossils, 218 Annesley, W. Esq. 20 Vol.. XXII. Anthophyllite of Norway, analysis of, 76 Antrim, county, geological review of, 161, 245 Apparatus for the 'analysis of gases, 83 Apparatus for destroying contagion in hospitals, 349 Archimedes, French translation of, 384 Arithmetic, improvement in, 261 Attraction, elective, see Elective Aubert, M. 359 B Babington, Dr. 159 Bakerian lecture, 238 Banks, Sir J. 27— His account of the method of cultivating the American cranberry, (vaccinium. macrocarpumj at Spring Grove, 216 Barclay, Dr. 79 Barlow, P. Esq. on polygonal numbers* in answer to Mr. Gough, S3 Baryiic salts, composition of, 301 Basaltic country in Ireland, 161, 245 Bath and West- of-En gland Society, re- port of a committee of, appointed to investigate the cla:m of the Right Hon. Lord Somerville to a premium '* for the greatest number and most profit- able sort of sheep," 327 Beddoes, Dr. 158 Belemnite, or thundar-puk, its nature, &c. 69 f Bengen promontory, and its stratifica- tions, 163, 245 Bernouilli on the propagation of sound* 117 Berzelius, Professor, 20— His experi- ments on the deoxidation and amaU gamation of the compound basis of ammonia, 54 b BUlingsley, INDEX. Biilingsley, J. Esq. his mode of hus- bandry, 354 Blavicr, M. his account of some ferru- ginous rocks, serving as*iubstitute$ for emery, 74 Bode, Mr. letter to, on comets, ice. ■ ' 206 . Bonvoisin, his two varieties of diopside, 14 Botanical gardens at St. Vincent's* 380 Boumon, D>, on the mineralogy of Dauphiny, 125 Brande, Mr. W. on the differences in the structure of calculi which arise from their being formed 'in different parts of the urinarv passages ; and on the effects that are produced upon them by the internal use of solvent medicines, in a .letter to E. Home, Esq. 35— Observations thereon, 51 Broad, Mr. J. his gauge or measure for standing timber, $24 Brodie, Mr. his anatomical description of the wombat, 179 Brown, Mr. R. 177— On the, germina- tion of the zamia of New Holland, 359 Buffon's hypothesis of the inequalities of the earth's surface, 249 Eurrow, Rev. E J. account of his go- c. Buxton, Dr. 79 iCfeahr Mr. C I.»\ his 'improvement in train pLr<-> for »-*r>ii.ges on mil-roads, 339 Cadet, M. communication from, orvthe analysis of ihr EhriUH medicine called James's powder, 316 CUculi.m .the human body, structure of, 35, 51 Camphor purified by means of potash, 176 Cancer, effects of oxide of iron in cases ♦ of, 79 Canvass, improved method of painting, 373 Carmichael, Dr. on the effect of oxide of iron on cancer, and the uses of oxide of iron in the blood, 79 Cassini, M. on the effects of gravity on the pendulum, 136 Cavanillcs' description of the Dahlia, 225 Cayley, Sir G. his plan for an improved theatre, 241 Chalanches, silver mine and mountain of, described, 124 Cheltenham water, artificial, 139 Chenevix's paper on James's powder, 316 Cholmeley, M. 159 Clarges, Sir T. on life boats, 20 Clennell, Mr. J. 158 Cline, Mr. 159 Coal- formation near Durham, 76 Coal, fossil, its distribution in the bowel* of the earth, 68 Coal gas, experiments on, 92, 145 Coffee, a British vegetable substitute for, 70 Comet, observations on that of last au tumn, 3 Comets, are solid bodies, 10— and lu- minous, 12— ,vee also 206— Tails of, more dense than has hitherto been supposed, 8— Not vapours, 13, 212 —Their extent, 13 Cook, Mr. B. his observations on the universal distribution of fossil coal, answered, 68— His second letter on gas lights, 145— On the substitution of iron for mahogany and other ex- pensive kinds of wood in articles of furniture, 287 Cooper, Mr. A. 159 Contagion, fumigations for stopping, 344 Coral, its formation, 157 Coral, colouring matter of, 219 C. O. T. his query on accidents fre- quently happening to dies with which medals are struck, 383 ' Coulomb, M. 308 Couplet, M. his experiments with the pendulum, 136 Cranberry, INDEX. Cranberry, American, culture of, 216 Creighton, Mr. 87 Cretinism, an account of, 294 Cruickshank, Mr. his experiments on gasses, 86 Cryolite, its characters, &c. 237 dimming, Mr. on the vibrations of a balance, 137 Curry, Dr. 159 Cnvler, M. his description of the wombat, 178 D. Dahlia, cultivation of, 224 Dalby, Mr. 11 Dalton, Mr. his experiments on gases, 86 Darwin, Dr. 355 Davy, H. Esq. his» electro-chemical re- searches on the decomposition of the earths, with observations on the me- tals obtained from the alkaline earths, and on the amalgam procured from ammonia, 54— .On the construction of galvanic batteries, 150— Results of his experiments on ammonia, sul- phur, phosphorus, &c. 238 Delamether.e, J. C. on the anthophyl- lite, 76— See also 309, 312 Delphinus melas, a new species of whale, 81 Perry, county of, geological observa- tion on, 161, 245 Dies, query on the accidents which hap- pen to them, 383 Pietrich, M. 125 Diopside, a new species in mineralogy, remark* on the, 14 — Description of, 16 Dirom, General, 79 Dolomieu on the mountain of Chalan- ches, 125 Dubuat's hydraulic experiments, 104, 112 Dudley mineral water, 266 Duhamel's experiments on the albur- num of trees, 27 Dunbar, Mr. J. on the cultivation of common flax as an ornamental plant in the flower-garden, 264 E. East Lothian, see Lothian Eclipses of the satellites of Jupiter, 153 E. F. G. H. on the utility of a series in finding a fluent, 213. Elective Attractions, table of, in tech- nical hexameters, 305 Electricity, 54 Electrical attractions and repulsions, es- say on, £08 Ember goose, see imber Emery, a substitute for, 74 Evaporating house for salt works, 151 Euler on the propagation of sound, 117 — His theory of the vibration of light, 210 Farcy, Mr. J. on the supposed univer- sal distribution of fossil coal, and on trie nature and situations of the ex- traneous fossil belemnite, called Thun- der pick, 68— On the conversion of French weights and measures into English, 337 Faujas, de St. Ford, on the mountain of Chalanches, 125 Filtrating well for rain water, 353 Fish, non-descript, 319 Flax, cultivated as an ornamental planj, 264 Fleming, Rev. J. on the narwhal or sea unicorn, 78 Fleury, M. on the effects of fumiga- tions with oxigenized muriatic acid, 346 Flinders, Capt. 177 Floor-cloths, improved manufacture of, 373 Fluent, utility of a series in finding, 213 Fossils, on the existence of animal mat- ter in, 218 Fossil coal, supposed universal distribu- tion of, 68 b 2 Fourcroy, INDEX. Fourcroy on calculi, 30 Fox, Mr. 159 French gold mines, 234, 279 French weights converted into English, 337 FYuit tree, propagation of in the Chi- nese method, 322 Fullerton, Col. 79 Fumigations to destroy contagion, 344 Gartner's vitellus of seeds, 357 Galvanism, 149— Applied in, cases of "deafness, 260 Gambir, observations on the, 3G6 Gas lights, 145 Gases, apparatus for the analysis of, 83 Gauge for standing timber, 324 Gay Lussac and Thenard, their experi- ments to ascertain the true nature of alkalies and earths, 63, et scq. Geoffroy, M. his description of the wombat, 178 Geology, 1 73, 245 Germination of seeds, 355 Gerstner's hydraulic experiments, 1 07 Giant's Causeway, 161, 164, 245 G. K. M. on the construction of galva- nic batteries, 149 Goitres and idiots of Switzerland, 294 Gold mines in Fiance, 234, 279 Goldingham, J. Esq. his observation of the eclipses of the satellites of Ju- piter at Madras, 153 Goniometer, described, 1 Gough» John, Esq. on polygonal num- bers, 33— <-His abstract of a meteoro- logical journal for the years 1807 and 1808, kept at Middleshaw, near Ken- dal, 305 Gowen, J. R. Esq. his account of a well for preserving and filtering rain- water for domestic purposes, where ,i supply of spring water was not easily to be obtained, 353 Grasses, memoir on, 318 Gravelly complaints, inquiry into the cause and cure of, 47 Gravity, effects of on time-pieces, 134 . Greathcad's life boat, history of, 21 Greene, R. Esq. his account of a sim- ple aud economical method of pre- paring an artificial Cheltenham water^ highly impregnated with carbonic acid (fixed air), 139 Grew, on the circulation of sap in trees, 29 Grcv, Mr. his electrical experiments, 314 Guettard, M. 125 Gutta gambeer, see Gambir Guyton-Morveau, M. his observations on the use of acid fumigations in pu- rifying the air and stopping the pro- gress of contagion, and the most sim- ple means of completely obtaining this effect, 344 H. Haighton, Dr. 159 Harrington, Dr. R. 239 Harris, Mr. the instrument maker, 1 Hatchett, Mr on the colouring matter of red eoral, 219 Hauy, M. his description of the species in" mineralogy called Diopside, 14— His mineralogical classes, 128 »' Hayter, Mr. C. his improved addition and multiplication tables, 261 Heberden, Dr. 57 Henry, Dr. \V. his description of an apparatus for the analysis of the com- pound inflammable gases by slow com- bustion, with experiments on the gas from coal, explaining its application, 83 H erica rt de Thury, *ee Thury Hernandez' description of the dahlia, 224 Herschel, Dr. his observations of a comet, made with a view to investi- gate its magnitude, and the nature of its illumination, 3, 206— His account of a new irregularity lately perceived in the apparent figure of the planet Saturn, 100 Hire, INDEX. Hire, M. De la, on the vibration of the pendulum, 136 Hisinger, M. 20 Home, E. Esq. letter to, on calculi and solvent medicines, 35— His ob- servations thereon, 51 — On some pe- culiarities in the structure of the wombat, 177 Honore, M. De St. 105. Hook, Dr. 158 Hospitals, apparatus for destroying con- tagion in, 349 Howison, Dr J. his account of the Chinese method of propagating fruit- trees, 322 Hunter, W. Esq. on Nauclea Gambir, the plant producing the drug called Gutta Gambeer, with characters of two other species, 366 Husbandry, oxen used in, with the ad- vantage, 330 Hydraulics, 104 1. Idiots of Switzerland, 294 Imber goose, description of, 23% 259 Instrument for gauging standing timber, 324 Iris Pseudacorus, seeds of, a substitute for coffee, 70 Irish geology, 161, 245 Iron, preparations of, their uses in cases of cancer, and their general effect upon the blood, 79 Iron proposed to be substituted for ex- pensive kinds of wood in furniture, 287 J. James's powder, analysis of, 316 Jameson, Professor, 78— His account of oryctognostic characters and geognos- tic relations of the mineral cryolite, 237 Jupiter's satellites, their eclipses, 153 K. JCemble, Mr. letter to, on an improved plan for theatres, 243. Kemp, Mr. 239 King, Mr. 158 Knight, T. A. Esq. on the origin and office of the albernum of trees, 27 — On the variegation of plants, 370 Koula, anatomical structure of, 177 Kraken of Norway, 77 Lacepede on the sea unicorn, 73 Lagrange on the propagation of sound, 117, 124 Laing, M. Esq. on a sea snake cast a- shore in Orkney, 77 Laskey, Mr. on several subjects m natural history, 237 — On the'Scotish testacea, Sib Laugier, M. 129 Le Cain, see Caan. Lectures, medical and surgical, 159 Lclivec, M. his account of an econo- mical method of evaporating the water of brine springs, employed at the- salt works of Moutiers, in the department of Mont Blanc, 151 X,ibes, M. his experiments on electrical attractions and repulsions, 309 Life-boats, general account of, 20 Light of the sun, what it is, 206 Lindsay, M. his account of the germi- nation of ferns, 3G4 Loat, Mr. J. his contrivance for filtrating and preserving rain-water for domestic purposes, 353 Lothian, East, observations on its mi- neralogy, 77 Luc, M. De, on comets, 206 Lugt, M. his experiments on electrical attractions and repulsions, 313 Lukin's patent life-boat, 20 M. Mackenzie, Mr. his account of the coaU formation near Durham, 76 Macknight, Dr. 79 Malacarni, on cretinism, 295 Marcet, Dr. 159 MarsuMi, INDEX. Marsilli, Count, on the colouring matter ' of red coral, 219 Medals, queries respecting the accidents which occur in the striking of, 383 Memoria technica for double elective attractions, 304 Menowvilleon theDahlin, 225 Menteith, C. S. Esq. 79 Mermaid of the Northern Ocean, 77 Metallization of the alkalies and earths, 60 Meteorological Journal for December, 80-—January, 160— February, 240— March, 319 , For the years 1807 and 1808, k^ptat Middleshaw, near Kendal, 305 Mineral waters, 139 Mineralogy of Chalanches, 124— of East Lothian, 77 M'nbel, on the geneiation of the bark of trees, 29 Mojon, Dr. on the use of acid fumiga- tions for destroying noxious effluvia, 345 Mongez, M. on the mineralogy of the mountain of Chalanches, 125 Montagu, G. Esq. his account of a non- descript fish, 319 Multiplication table on a new plan, 262 Mussite, a variety of the diopside, de- scribed, 19 N. Narwhal, or sea unicorn, 78 Natural history, 76, 237, 318 NaucleaGambir, seeGambir Nectarines and peaches produced na- turally on the same branch, 284 Neiil's Tour in the Shetland Islands, 82 Neill, Mr. P. his description of a rare species of whale, 77, 237 Newtonian theory of colours, 210 Nondescript fish, 319 Number, polygonal, 33 Numeration table, on a new plan, 263 O. Ogilby, Dr. his mineralogy of East Lothian, 77, 78 Ornithology, questions in, 23C—-:\n9 swered, 259 Otter, remarkable instance of intrepidity in the, 237 Oxen used in husbandry, advantages of, 330 P. Parkinson, Mr. . on the existence of animal matter in fossils, 156, 218 Paterson, Lieut -Col. 177 Peaches, see Nectarines Pearson, Dr. on calculi, 39, 50 — His analysis of James's powder, 316 Pelletier's electrical experiments, 61 Pepys, W. H. Esq. on the changes pro- duced on atmospheric air and oxigen gas, by respiration, 180 Phials for preventing and removing con- tagion, 347 Philochemicus on the purification of camphor, 176 Picart, M. on the vibration of the pen- dulum, 136 Piggot, Mr. 3 Plants, variegation of, 370 Playfair's hypothesis of the inequalities of the surface, of the earth, 249 Platina springs for watches, 148 Polygonal numbers, 33 Pontin, Dr on the deoxidation and amalgamation of the compound basis of ammonia, 54 Portmoon described, 161, 245 Prochaska, professor, his dissection of the skull of a Cretin, 299 Propagation of fruit trees, the Chinese method, 322 Pully, M. his analysis of the English medicine called James's powder, 316 R. Rail-roads, improvement in, 339 Reeve, Dr. his account of cretinism, a species of mental imbecility endemic in some parts of Switzerland, 294 Reports of the Preyentive Medical In- stitution at Bristol, 153 Respiration, changes produced by it on atmospheric air, and oxigen gas, 180 Richardson; I N D E X. Richardson, Dr. W. on the alteratio ns that have taken place in the structure Of rocks, on the surface of the basaltic country, in the counties of Derry and Antrim, 161, 245 Richer, his experiments with tie pen- dulum, 135 Royal Society, proceeding. in, 2^8 Robison, professor, his hydraulic ex- periments, 104 Ru.ssel, J. E*q. 79 S. Saint, W. Esq. on ascertaining square numbers and biquadrates by inspec- tion, 291 Salisbury, R. A. Esq. his account of nectarines and peaches naturally pro- duced on the same branch, 284— On the different species of dahlia, and the best method of cultivating them in Great Britain, 224 — Letter to, on the variegation of plants, 370 Salt works, improved evaporating house ■ for, 151 Sap of trees, circulation of, 27 Satellites of Jupiter, their eclipses, 153 Saturn, its irregular figure, 100 Saunders, Dr on mineral waters, 140 Saussure, M. De, his hypothesis of the circulation of sap in trees, 28— On the Cretins in Switzerland, 295 Schrieber, M. on the mineralogy of Chalanches, 124 Scientific news, 76, 156, 2:37, 318,384 Scott, Mr. J. on the superiority of pla- tina for making the pendulum spring of watches, 148 •Sea snake of the Northern Ocean, de- scription of, 77, 237 Sea unicorn, 78 Seeds, structure of, 354 Series useful in finding a fluent, 213 Sheep, most profitable sort of, 327 Shells, British, a collection presented to the Wemerian Natural History Society, 238 Sims, Dr. 232 Singer, Mr. G. 79 Skrimshire, Mr. W. his account of a British vegetable product, that may be substituted for coffee, 70 Smirk, Mr. 241 Smith, Dr. J. E. his inquiry into the structure of seeds, and especially into the true nature of that part called by Gxrtner the Fitel/w, 354 S. N.'s questions in ornithology,, 233— Answered, 259 Soda water, method of preparing,' 142 Solvent medicines, 47 Somerville, Lord, investigation of his claim to a premium for breeding the most profitable sort of sheep, 327— On the advantages of the use of oxen and neat cattle in husbandry, 330 Springs for watches, 148 Square numbers, rules For ascertaining, 291 Staunton, Sir G. 296 Stewart, C. Esq. 79 Sun, its light does not emanate from its body, 207 T. T. on the use of galvanism in deafness, 260 Tables in numeration, addition, and multiplication, on a new plan, 262 Testaceaof Scotland, 318 '< The Tradesman, or Commercial Ma- gazine," 158 Theatre, plan for an improved one, 241 Thenard, see Gay-Lussac Thompson, Dr. 79 Thouin, M. on the culture of the dahlia, 225 Thunberg, Professor, 228 Thunder pick, see Bclemnite Thury, H. De, his mineralogies! de- scription of the mountain and silver -mine of Chalanehes, 124— On the gold mines in the department of the here, 234, 279 Timber, instruments for measuringj 324 Time-pieces INDEX. Time-pieces affected by gravitation, 134 Toad, a living one, found in a bed of clay, 237 Tondi, M. 19 Tonnelier, M. on the diopside, a new species in mineralogy, established by M. Hauy, comprising two varieties found hi the Piedmontese Alps by M. Bouvoisin, &c. 14 Traill,, Dr. his description of a new species of whale (delphinus melasj, 81 — On the habits of the imber and northern divers, 2 J9 Vaixdv'uim macrocarpum^ the American cranberry, method of cultivating, 2 16 Vauque.l'm on calculi, 39, 50 Variegation of plants, 370 Vincent, St. botanical garden in the island of, 380 W. Walker, P. Esq. 79 Watch-springs of platina, 148 Water impregnated with fixed air, method of preparing, 139 Water of a mineral spring near Dudley, Worcestershire, analysed, 267 Watson, James, Esq. 81 Weights, French and English, 337 Welden, Mr. W. his analysis of a mineral water, near Dudley, Wor- cestershire, 266 Wemerian Natural History Society, proceedings in, 76, 237, 318 Whale, rare and new species of, 81, 237 Wilkins, Mr certificate from, relative to Mr. Broad's gauge for measuring standing timber, 327 Willdenow, Professor, on the culture and generic character of the dahlia, 227 Wilson, Mr. his life-boat, 22 Wilson, Mr. his experiments on the rays of light, 210 W. N. on the effects of gravitation on time-pieces, 139 — On Mr. Hayter's new tables in arithmetic, 261 Wollaston, Dr. W. H. communication from, on cretinism, 294 Wombat, anatomical structure of, 177 W oodrord , E. J . A . Esq . 232 Woodward, Dr. mistaken in supposing the thunder-pick to be a crystal, 69 Wouldhave's invention for going to sea in a storm, 21 Wright, Dr. 79 X. X. on the effects of gravity on the balance of a watch, compared with those on the pendulum of a ,cJock, 134 Young, Dr. T. his hydraulic investiga- tion, subservient to an intended Cronian lecture on the motion of the blood, 104 — His Memoria Technim for double elective attractions, 304 Yule, Dr. 79 — His memoir on grasses 318 END OF THE TWENTY-SECOND VOLUME. Stratford, Printer, Crown-Court, Temple-Bar.