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THE Bakerian Lecture, on some new Phenomena of Chee mical Changes produced by Electricity, Saale y the Decomposition of the fixed Alkalis, and the Exhibition of the new Substances which constitute their Bases; and on the general Nature of alkaline Bodies. By HuMpPHRY Davy, Esq. Sec. R.S. M.R.LA. 3 II. On the Opinions that have prevailed respecting the ‘Na- ture of Alkalis and Earths. By a Correspondent 18 Ill. Descripiion of a new Compensation Pendulum. By Mr. H. Warp, of Blandford, Dorsetshire .. .. 22 IV. Memoirs of the late Erasmus Darwin, M.D... 30 V. On Oxalic Acid. By Tromas Tuomson, M. D. F.R.S. Ed. Communicated by CHuarves a ge Esq., F.R.S. A VI. ees on the ee idee or ie, ce Mied Phenomenon of Incombustibility. Translated from the Tialian of Louis Sementin1, M.D., chief Professor of Chemistry in the Royal University of Naples ... 47 VII. Analysis of the lately discovered Mineral Waters at Cheltenham ; and also of other Medicinal Springs in its Neighbourhood. By Freperick -Accum, M.R.I. 4, Oper ative Chemist, Lecturer on Practical Chemistry and on Mineralogy and Phagniacy nese, OR NO 87 VIII, On the Nature of the Earths... 26 OD IX. Description of a Machine for beating out Hemp- seeds and Flax-seeds ; invented by Mr. EzeKIEL CLEALL, of | West Coker, Somersetshire .. 66 X. Description of a Machine for breaking Hemp, with Ob- servations on the Culture of Hemp in Canada, By Wit- LIAM Bonn, Esq., of Canada .. 69 XI. Olservations on the Breeding of Rabbits ‘ond ‘other Animals, in Canada. By WitLiaM Bonn, Esq., a Canada... XII. Memoir upon ‘the Desulphuration of Metals. By M. GUENIVEAU, Engineer to the Mines .. SIL. Report of Surgical Cases in the City and Fite Dispensaries, for April, May, and June, 1208. With two gies of Dropsy of ihe Ovarium. By Jouyx Taunton, Sls je gic 4 obw ag ie oh baie wit 6 GE hha ames 6 Or Vol. 32. No. 127. Dec. 1808. a ATV. Noe ‘ CONTENTS. XIV. Notices respecting New Books .. 2.2 «. «- 88 VE Intelligence and Miscellaneous Oi Pols 7 Se XVI. Observations on Architecture. By J. R. mei | XVII. The Bakerian Lecture, on some new Phaenomena of Chemical Changes produced by Electricity, particularly the Decomposition of the fixed Alkalis, and'the Exhibition of the new Substances which constitute their Bases ; and on the general Nature of alkaline Bodies. By By HumMPHRY Davy, Esq., Sec. R.S, MR.LA.* . oY NO] XVII. An Account of the Application of the Gas from Coal to ceconomical Purposes. By Mr. Witt1am Murpocu. Communicated by the Right Hon. Sir JosErH BANKS, Bart. K. B. P.R.S. : X) WHS XIX. Description of an improved Ship “Stove. Bi y Mr, JosEpH CoLLieR, of Crown-Sireet, Soho, London 119 XX. Method of preparing and applying a Composition for Painting in Imitation of the Ancient Grecian’ Manner, - called Encaustic Painting. By Mrs. ae of Roi- tingdeans near Brighton ee ». 120 XXI. Essay upon Machines in Generali Br y M. CaRNOT, ~ Member of the French Institute, @e.@e. 0. os ¥94 XXII. Description of improved Tram-Plates for Carriages on Rail Roads. By Mr, Cuartes Le Caan, of Lhanelly, Wales 2 230 XXIII. On, the Inconvertibility of Bark into Alburnum. By THomas ANDREW KNIGHT, Esq. »» F.R.S. Ina Letier to. Sir JOSEPH Banks, KB BiB SRonw oe 14 XXIV. Analysis of various Kinds eee Pit-Coal, “By Davip MUSHET,. Eisgiy Rew \rr as POV e140 XXV. The Bukerian Lecture, on some new , Phenomena of ‘Chemical Changes produced by Electricity, particularly the Decomposition of the fixed Alkalis, and the Exhilitien of the new Substances which constitute their Bases; and on the general Nature of alkaline Bodies. By HUMPHRY Davy, Esg., Sec. B.S. MM Ribrd 00 POR AG XXXVI. Successful. Application of the Magnet, emplor yed to extract a Fragment of [ron out of the human Eye, which had been lodged there about five Months. -By Mr: Wit- LIAM Preram, Sen., of Tenterden AD ka die XXVIII. Remarks on the Incombustible. Man °.. >... ¥57 XXVIII. Memoirs of the late Enasmus Darwin, M.D. 158 XXIX. 4A Leiter on the Differences in ‘the Structure of Caleuli, 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 Medicines, from Mr. WittiaAm BRANDE to EVERARD Home, Esq. -» ERS, f ; ER, Ta- pe + 08% - | 90 ee ee 167° , a“ -CONTENTS. XXX. Tables exhibiting « collective View of all the Frigo~ rific Mixtures contained in Mr, Wauker’s Publication, 1808 os 5 ak Wet CRS, CREE 77 XXXI.. Notices respecting en Bohs al: srs. 6) PSM XXXII. Proceedings of Learned Societies... .. 184 XXXIIL.. Intelligence and Miscellaneous Articles .. 191 XXXIV. Tle cieathewmronh 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 Humpury Davy, Esq., Sec. R.S. M.R.ILA. Prof. Chem. RD .. - J93 XXXV. An Inquiry into the Structure of Seeds; and. espe- cially into the true Nature of that Part.called by Gertner the Vitellus. By James EpwarbD abi M.D. F.R.S. PLES A004); .. 888 XXXVI. 4 Letter on the D ifferences in the. Structure of Calculi, which arise from their being formed in different Parts of the urinary Passages; and on the Effects that are protuced upon them. by the tmternal Use of solvent — Medicines, from Mr. Witt1aM BranDe to EVERARD Home, Esq.; FB. Siw sw: 234 KXXVII. Some Observations on Mr. pa s Paper on Calculi. By EveERARD Home, Esq. ke RiSoO Giese XXXVIII. On the Changes produced in Atmospheric Air and Oxygen Gas by Respiration. By W. Aten, Esq., PB R3S,,..\and?W.H. Pepys, Esq.,° FURS. & 3560949 XXXIX. On Commerce. By Mr. James GraHAmM, of Berwick-upon-Tweed. .. ese SOOT XL. On the Means employ yed | an 2 Spain for the Cure. of Hydrophobia .. S| Byer XLI. 4 Description of the Apparatus by y which the French Experiment on the Decomposition of Potash has been made at the Royal Institution .. ye) aa] XLII. Description of an Apparatus for. the “Analysis of the Compound Inflammaile Gases by Slow Combustien ; with Experiments on the Gas from Coal, explaining its Application. By WittiAM Henry, M. D. Vice-Pres, of the Lit. and Phil. Society, and Physician to the In- jrmary, at Manchester. Communicated "y H. Davy, Hsq. Sec. R. Si.) 0s 277 - XLIIL. Liewtenant Beit’s Invention for preserving the Lives of Mariners in Cases of Shipwreck... 294 XLIV. On the Origin and Office of the Alburnum a Trees. In a Letter from T. A. Knicut, Esq. » F.R.S., to Sir cig BPH: BANKS; bart. K.By PsRsSee lew Sew $999 XLY. On . - CONTENTS. XLV. On the Variegation of Plants. In a Letter to RICHARD _ Antuony Sauispury, Esq., F.R.S. and L.S., by THo- mas ANDREW Knicut, Esq.,-F.R.S. and L. S.” 306 _ KLVI. Experimenis relative to Coals and Cokes obtained from Wood and Pit-coal. By Davin Musuet, Esq. 309 XLVIL Some interesting Additions to the Natural Elis- “tory of Falco cyaneus and pygargus, together with Re- marks on some other British Birds. By GEorce Mon- taGu, Esq. F.L.S.... "315 ALVIII, Memoirs of the late Enaswus Darwin, M.D. 329 XLIX. Materials for a History of the Prussiates. By M. Proust .. . oe 336 L. Some Account of a remarkable Case of Tetanus 357 LI. Report. of . Surgical. Cases in. the. City and. Finsbury Dispensaries, for July, August, and September, 1808. With the Termination and Appearances on Dissection, of the Case of Dropsy in the Ovarium, A he ed to in p. 86.- By Joun Taunton, Esq. . : sf S63 LII. Proceedings of Learned Societies... eve 867 LUI. Intelligence and Miscellaneous Articles, en. S38 TO THE | Dkr PHILOSOPHICAL MAGAZINE: §. The Bakerian Lecture, on some new meee of Che- mical Changes produced by Electricity, particularly the Dera of the fixed Athalis, and the Exhibition of the new Substances which constitute their Bases; and on the general Nature of alkaline Bodies. By Houmpury Davy, Esq. SeceoR. S. MeR.LA.* pial tT Introduction. ; Ix the Bakerian Lecture which I had the honour of present- ing to the Royal Society last year, I described a number of decompositions and chemical changes produced in substances of known composition by electricity, and I ventured to con- clude from the general principles on which the phenomena were capable of being explained, that the new methods of investigation promised to lead to a more intimate knowledge than had hitherto been obtained, concerning the true ele- ments of bodies. : ' This conjecture, then sanctioned only by strong analo- gies, I am now happy to be able to support by some con- clusive facts. Jn the course of a laborious experimental ap- plicatron of the powers of electro-chemical analysis, to bodies which have appeared simple when examined by com- mon chemical agents, or which at least have never been decomposed, it has been my good fortune to obtain new and singular results. Such of the series of experiments as are in a tolerably- mature state, and capable of being arranged in a connected order, I shalj detail in the following sections, particularly * From Philosophical Transactions for 1808, Part 1. A2 those 4 _ On the Decomposition and_Composition - those which demonstrate the decomposition and composition of the fixed alkalis, and the production of the new and ex- traordinary bodies which constttute their bases. In speaking of novel methods of investigation, I shall not fear to be minute. When the common means of chemical rescarch have been employed, I shall mention only results. A historical detail of the progress of the investigation, of all the difficulties that occurred, and of the manner in which they were overcome, and of all the manipulations employed, would far ‘exceed the l?mits assigned to this lecture. It is proper to state, however, that when general facts are men- tioned, they are such only as have been deduced from pro- cesses carefully performed and often repeated. II. On the Methods used for the Decomposition of the fixed Alkalis. The researches I had made on the decomposition of acids, and of alkaline and earthy neutral compounds, proved that the powers of electrical decomposition were proportional to the streneth of the opposite electricities in the circuit, and to the conducting power and degree of concentration of the materials employed. Tn the first attempts that I made on the decomposition of the fixed alkalis, I acted upon aqueous solutions of pot- ash and soda, saturated at common temperatures, by the highest electrical power I could command, and which was produced hy a Souibiasion. of Voltaic batteries belonging to | the Royal Institution, containing 24 plates of copper and zinc of 12 inches square, 100 plates of six inches, and 150 of four inches square, charged with solutions of alum and nitrous acid; but in these cases, though there was a high intensity of action, the water of ihe solutions alone was affected, and hydrogen .and oxygen’ disengaged with the production of much heat and violent effervescence. The presence of water appearing thus to prevent any de- composition, I used potash in igneous fusion. By means of a stream of oxygen gas from a gasometer applied to the flame of a spirit lamp, which was thrown on a platina spoon containing potash, this alkali: was kept for some minutes in a strong of the fixed Alkalis. : . 5 astrone red heat, and ina state of perfect ‘fluidity. The spoon was preserved in communication with the positive side of the battery of the power of 100 of six inches, highly charged ; and the connection from the negative side was made by a platina wire. | By this arrangement some brilliant phenomena were pro- duced. The potash appeared a conductor in a high degree, and as long as the communication was preserved, a most in- tense light was exhibited at the negative wire, and a column of Hewes which seemed to be owing to the development of combustible matter, arose from the point of contact. When the order was changed, so that the platina spoon was made negative, a vivid and constant hght appeared at the opposite point ; there was no effect of inflammation round it; but aériform globules, which inflamed in the at- mosphere, rose through the potash. The platina, as cei have been expected, was consider- ably acted upon ; and ia the"Gieds when at bad been nega- tive in the highest degree. : The alkali was apparently dry in this se peeiblenn and it seemed probable that the inflammable matter. arose from its decomposition. The residual potash was unaltered ; it contained indeed a number of dark- ray metallic particles, but these proved to be derived from the platina. ‘ I tried several experiments on the electrization of potash rendered fluid by heat, with the hopes of. being able to col- Ject the combustible matter, but without success; and I only attained my object, by employing electricity as the common agent for fusion and decomposition. Though potash perfectly dried by ignition is a noncon- ductor, yet it is rendered a conductor by a very slight ad- dition of moisture, which does not perceptibly destroy its agoregation ; and in this state it readily fuses and decom- poses by strong electrical powers. A small piece of pure potash, which had been exposed for a few seconds to the atmosphere, so as to give conduct- ing power to the surface, was placed upon an insulated disc of platina, connected with the negative side of the battery of the power of 250 of six and four, in a state of intense Re activity ; a t 6: On the Decomposition and Composition activity ; : and. a platina wire, communicating with the po- “sitive side, was brought in contact with the upper surface of the alkali: The whole apparatus was in the open atmosphere. . Under these circumstances a vivid action was soon ob- served to take place. The potash began to fuse at both its points of electrization.. There was a violent effervescence at the upper surface 5. at the lower, or iegative surface, there was no liberation of elastic fluid; but small globules having a high metallic lustre, and baie precisely cae in visible characters to quicksilver, appeared, some of which burnt with explosion and bright flame, as soon as they were formed, and others remained, aud.were merely tarnished, and finally covered. by a white film which formed on their surfaces. These globules, numerous experiments soon showed to be the substance I was in search of, and a peculiar inflammable principle the basis of potash. I found that the platina was in no way connected with the result, except as the medium for exhibiting the electrical powers of decomposition ;, and a substance of the same kind was produced when pieces of copper, silver, gold, plumbago, or even charcoal were em- ployed for completing the circuit. ‘ The phenomenon was independent of the presence of ail 5, T found that it took place when the alkali was in the vacuum of an exhausted receiver. The substance was likewise anaes from potash. fused by means of a lamp, in glass tubes confined by mercury, and. furnished with SH ee inserted , platina wires by which the electrical action was transmitted. But this ope~ ration couid not be carried ‘on for any considerable times the glass was rapidly dissolved by the action of the alkali, and ae substance soon penetrated through the body. of the tube. Soda, when acted upon in the same manner as potash, exhibited an analogous result; but the decomposition de- manded greater intensity of action in the batteries, or the alkali was required to be in much thinner and smaller pieces. With the battery of 100 of six inches in full activity I ob- tained good results from pieces of potash weighing from 40: io 70 grains, and of a thickness which made the distance of the of the fived Alkalis. 7 the electrified metallic surfaces neariy a quarter of an inch ; but with a similar power it was impossible to produce the effects of decomposition on pieces of soda of more than 15 or 20 grains in weight, and that only when the distance bes tween the wires was about 4th or t,th of an inch. The substance produced from potash remained fluid at the temperature of the atmosphere at the time of its production ; that from soda, which was fluid in the degree of heat of the alkali during its formation, became solid on cooling, and appeared having the lustre of silver. When the power of 250 was used, with a very high charge fot the decomposition of soda, the globules often burnt at the moment of their formation, and sometimes violently exploded and separated into smaller globules, which fiew with great velocity through the air in a state of vivid combustion, producing a beautiful effect of continued jets of fire. Ill. Theory of the Decomposition of the fixed Alkalis ; their Composition, and Production. As in all decompositions of compound substances which I had previously examined, at the same time that combus- tible bases were developed at the negative surface in the elec- trical circuit, oxygen was produced, and evolved or carried into combination at the positive surface, it was reasonable to conclude that this substance was generated in a similar manner by the electrical action upon the alkalis; and a number of experiments made above mercury, with the ap- paratus for aoe external air, proved that this was the case. When solid potash, or soda in its egnductine: state, was included in glass tubes furnished with electrified platina wires, the new substances were generated at the negative surfaces; the gas given out at the other surface proved by | the most delicate examination to be pure oxygen; and un- , less an excess of water was present, no gas was evolved from the negative surface. ‘In the syuthetical experiments, a perfect coincidence like- wist will be found. A 4 iy I mene ? ~~ . 8 - On the Decomposition and Composition «I mentioned that the metallic lustre of the substance frora potash immediately became destroyed in the atmosphere, , and that.a white crust formed upon it. This crust I soon found to be pure potash, which immediately deliquesced, and new quantities were formed, which in, their turn at- tracted moisture from the atmosphere till the whole globule disappeared, and assumed the form of a saturated solution of potash *. When globules were placed in appropriate tubes contain- ing common air or oxygen gas coufined by mercury, an absorption of oxygen took place; a erust of alkali instantly formed upon the globule; but from the want of moisture for.its solution, the process stopped, the interior being de- fended from the action of the gas. . _ With the substance from bodes the appearances and offanils were analogous. When the substances were strongly heated, confined in given. portions of oxygen, a rapid combustion with a bril- liant white flame was produced, and the metallic globules were found converted into a white and solid mass, which in the case of the substance from potash was found to be pot- ash, and in the-case of that from soda, soda. Oxygen gas was absorbed in this operation, and nothing -emitted which affected the purity of the residual air. : The -alkalis produced were apparently dry, or at least contained no more moisture than might well be conceived to exist in the oxygen gas aoaaciie and their weights considerably exceeded those of the combustible matters con- ° sumed. The processes on which these conclusions are founded will be. fully described hereafter, when the minute details which are necessary will be explained, and the proportions * Water likewise is decomposed in the process. We shall hereafter see that the bases of the fixed alkalis act upon this substance with greater energy than any other known bodies. The minute theory of the oxidation of the bases of the alkalis in the free air, is this:—oxygen gas is first attracted by them, and alkali formed. © This alkali speedily absorbs water. ‘This water is again decomposed. Hence, during the conversion of a globule into alkaline- solution, there is a constant and rapid disengagement of small ee of gas. : , of ’ ee | ' of the fixed Alkalis. 9 of oxygen, and of the respective inflammable substances whieh enter Into union to form the fixed alkalis, will be givert. Tt appears dheay that im these facts there is the same evi- dence for the decomposition of potash and soda into oxygen and two peculiar substances, as there is for the decomposi- tion of sulphuric and phosphoric acids and the metallic ox- ides into oxygeu and their respective combustible bases. In the analytical experiments, no substances capable of decomposition are present but the alkalis and a minute por- _ tion of moisture ; which seems in no other way essential to the result, than in rendering them conductors at the sur- face: for the new soheeanees are not generated till the inte- rior, which is dry, begins to be fused ; they explode when in rising through the Gael alkah they come in contact with, the heated moistened surface ; they cannot be produced from crystallized alkalis, which contain much water; and the effect produced by the electrization of ignited potash, which contains no sensible quantity of water, confirms the opinion of their formation independently of the presence of this sub- ‘Stance. 3 The combustible bases of the fixed alkalis seem to be re- , pelled as other combustible substances, by positively elec- trified surfaces, and attracted by negatively electrified sur- faces, and the oxygen follows the contrary erder*; or, the oxygen being naturally possessed of the negative energy, and the bases of the positive, do not remain in combination when either of them is brought into an electrical state op- posite to its natural one. In the synthesis, on the contrary, the natural energies or attractions come in equilibrium with each other; and when ‘these are in a low state at. common temperatures, a slow combination ts effected > but when they are exalted by heat, a rapid union is the rastilts and as in other like cases with the production of fire.—A aah of circumstances relating to the avencies of the bases of the- alkalis will be immediately stated, and will be found to offer confirmations of these eu conclusions. : aes Bakerian Lecture 1806, page 28 of Phil: Trans. for 1807. IV. Qa ia eo". to On the Decomposition and Compositien - IV. On the Properties and Nature of the Basis of Potash. ms After I had detected the bases of the fixed alkalis, I had considerable difficulty to preserve and confine them so as to examine. their properties, and submit them to experiments $ for, like the alkahests imagined by the ‘alchemists, they acted more or less upon: almost every body to which they were exposed. The fluid substance amongst all those I have tried, on which I find they liave least effect, is recently distilled naph- tha.——In this material, when excluded from the air, they remain for manv days without considerably changing, and . their physical ‘properties may be easily examined in the at- mosphere when they are covered by a thin film of it. The basis of potash at 60° Fahrenheit, the temperature in which T first.examined it, appeared, as I have already men- tioned, in small globules possessing the metallic lustre,’ ‘opacity, and general appearance of mercury; so that when a globule of mercury was placed near a globule of the pe- alex: substance, it was not possible to detect a difference by the eye. At 60° Fahrenheit it 1s however:only imperfectly fluid, for it does not readily run into a globule when its shape is altered’; at 20° it becomes more flnid; and at 100° its flu- idity is perfect, so that different globules may be easily made — ‘to run into one. At 50° Fahrenheit it becomes a soft and malleable solid, which has the lustre of polished silver; and at about the freezing point of water it becomes harder and brittle, and when broken in fragments exhibits a crystallized texture, which im the microscope seems composed of beautiful facets of a perfect whiteness and high metallic splendour. To be converted into vapour, it requires a temperature approaching that of the red heat ; and when the experiment | is conducted under proper circumstances, itis found unal- | tered after distillation. It is a perfect conductor of electricity. When suite from the Voltaic battery of 100 of six inches. is taken upon a large globule in the atmosphere, the light is green, and combustion takes place at the point of contact only. When a small of the fixed Alkalis. if 2 small globule is used, it is completely dissipated with explo- sion accompanied by a most vivid flame, into alkaline fumes. It is an excellent conductor of heat. Resembling the metals in all these sensible properties, it is however remarkably different from any of them in specific gravity ; I found that it rose to the surface of naphtha di- stilled from petroleum, and of which the specific gravity was “861, and it did not sink in double distilled naphtha, the specific gravity of which was about 770, that of water being considered as one. ‘The small quantities in which it is pro- duced by the highest electrical powers, rendered it very difficult to determine this quality with mimuie' precision. Ff endeavoured to gain approximations on the subject by com- paring the weights of perfectly equal. globules of the basis of potash and mercury. J used the very delicate balance of the Royal Institution, which when loaded with the quan- ~ tities | employed, and of which the mercury never exceeded ten grains, is sensible at least to the ~j),th of a grain. Taking the mean of four experiments, conducted with great care, its specific gravity at 62° Fahrenheit, is to that of mercury as ten to 223, which gives a propoction to that of water hearly as six to ten; so that it is the lightest fluid body known. In its soird form it is a little heavier, but every in this state when cooled to 40° Fahrenheit, 1t swims in the double distilled naphtha. The chemical relations of the basis of tual are still more extraordinary than its physical ones. I have already mentioned its alkalization and combustion im oxygen gas.—I!t combines with oxygen slowly and with- out flame at all temperatures that I have tried below that of its vaporization.—But at this temperature combustion takes place, and the light is of a brilliant whiteness and the heat intense. When heated slowly in a quantity cf oxygen gas not sufficient for its complete conversion into potash, iid at a temperature inadequate to its inflammation; 400° Fah- repheit, forinstance, its tint changes to that of a red brown, and when the heat is withdrawn, all the oxygen is found to be absorbed, and a solid is formed of a grayish colour, which partly consists of potash and partly of the basis of potash in a lower 32 On the Decomposition and Composition a lower degree of oxygenation,—and which becomes potash by being exposed to water, or by being again heated in fresh quantities of air. The substance consisting of the basis of potash combined with an under proportion of oxygen, may likewise be formed: by fusing dry potash and its basis together under proper circumstances. The basis rapidly loses its metallic splendour; the two substances unite into a compound, of a red-brown colour when fluid, and of a dark gray hue when solid ; and this compound soon absorbs its full proportion of oxygen when'exposed to the air, and is wholly converted into potash. And the same body is often formed in the analytical ex- periments when the action of the electricity is intense, and the potash much heated. The basis of potash when introduced into oxymuriatic acid gas burns ‘spontancously with a bright red light, anda olin salt proving to be muriate of wee is foeaiee When a globule is heated in hydregen at a degree below its point of vaporization, it seems to dissolve in it, for the elobule diministes in volume, and the gas explodes with alkaline fumes and bright light, when suffered to pass into the air; but by cooling, this spontaneous detonating. pro- perty is destroyed, and the basis is either wholly or princi- pally deposited. The action of the basis of potash on water exposed to the atmosphere is connected with some beautiful phenomena. When it 1s thrown upon water, or when it is brought into contact with a drop of water at common temperatures, it decomposes it with great violence, an instantaneous explo- sion is produced with brilliant flame, and a solution of pure potash is the result. Jn experiments of this kind, an appearance often occurs ‘similar to that produced by the combustion of phosphuret- ted hydrogen ; a white ring of smoke, which gradually ex- tends as it rises into the air. When water is made to act upon the basis of potash out: of the contact of air and preserved by means of a glass tube under naphtha, the decomposition is violent ; and there i is 2 ‘much | y of the fixed Alkalis. 13 much heat and noise, but no Juminous appearance, and the gas evolved when examined in the mercurial or water pneu- matic apparatus is found to be pure hydrogen. When a globule of the basis of potash 1s placed upon ice it instantly burns with a bright flame, and a deep hole is made in the ice, which is found to contain a solution of potash. i The theory of the action aE the basis of potash upon water exposed to the atmosphere, thoueh complicated changes ~occur, 1s far from being obscure. The phznomena seem to depend on the strong attractions’ of the basis for oxygen and of the potash formed for water. The heat, which arises from two causes, decomposition and combination, is suffi- ciently intense to produce the inflammation. Water is a bad conductor of heat ; the globule swims exposed to air; a part of it, there is the greatest reason to believe, 1s dissolved by the heated nascent hydrogen; and this substance being ca-. pable of spontaneous inflammation, explodes, and commu- nicates the cflect of combustion to any of the basis-that may be yet uncombined. When a globule confined out of the contact of air is act-. ed upon by water, the theory of decomposition is very sim- ple, the heat produced is rapidly carried off, so that there is no ignition ; and a bieh temperature being requisite for the solution of the basis in hydrogen, this combination probably does not take place, or at least it can n have a momentary ex- istence only. The production of alkali in the decomposition of water by the basis of potash is demonstrated in a very simple and satisfactory manner by dropping a globule of it upon moist-. ened paper tinged with turmeric. At the moment that the globule comes into contact with the water, it burns, and moves rapidiy upon the paper, as Mf in search of moisture, leaving behind it-a deep reddish-brown trace, and acting upon the paper precisely as dry caustic potash. So strong is the attraction of the basis of potash for oxy- gen, and so great the energy of its action upon water, that it discovers and decomposes the small quantities of water contained 14 On the Decomposition and Composition contained in alcohol and ether, even when they are carefully pun od. ‘ ‘ In ether this decomposition is connected with an instruc- tive result. Potash is insoluble inthis fluid; and when the basis of potash is thrown into it, oxygen is furnished to it, and hydrogen gas disengaged, and the alkali as it forms renders the ether white and turbid. In both these inflammable compounds the energy of its action is proportional to the quantity of water they contain, and hydrogen and potash aze the constant result. The basis of potash when thrown into solutions of the. ymineral acids, inflames and burns on the surface. When it is plunged by proper means beneath the surface enveloped in potash, surrounded by naphtha, it acts upon the oxygen with the greatest intensity, and all its effects are such as may be explained frem its strong affinity for this substance, Tn sulphuric acid a white saline substance with a yellow. coating, which is probably sulphate of potash surrounded by sulphur, and a gas which has the smell! of sulphureous acid, and which probably is a mixture of that substance with hy- drogen gas, are formed. In nitrous acid, nitrous gas 1s disengaged, and mitrate of pee) formed. The basis of potash readily.combines with the simple in- Aancble solids, and with the metals; with phosphorus — and sulohur, it forms compounds similar to the metallic phospburets and sulphurets, When it is brought in contact with a ptece of phosphorus and pressed upon, there is a considerable action: they bes come fluid together, burn, and produce phosphate of potash, When the experiment is made under naphtha, their combi- nation takes place without the liberation of any elastic mat- ster, and they form a compound which has a considerably higher point of fusion than its two constituents, and which ‘yemains a soft solid in boiling naphtha. Tn its appearance it pertectly agrees with a metallic phosphuret, it is of the colour of lead, and when spread out has’a lustre similar to polished lead. When exposed to air at common eres tures, it slowly combines with oxygen, and become phos- phate of the fixed Aikalis, 15 phate of potash. When heated upon a plate of platina, fumes exhale from it, and it does not burn tll it attains the tempe- rature of the rapid combustion of the basis of potash. When the basis of potash is brought in contact with sul- phur in fusion, in tubes filled with the vapour of naphtha, they combine rapidly with the evolution of heat and light, and a gray substance, in appearance like artificial sulphuret of iron, is formed, which 1 kept in fusion, rapidly dissolves the glass, and becomes. bright brown. When this experi- ment 1s made in a glass tube hermetically sealed, no gas is liberated if the tube is opened under mercury ; but when it is made ina tube connected with a mercurial apparatus, a small quantity of sulphuretted hydrogen is evolved, so that the phznomena are similar to those produced by the union of sulphar with the metals in which sulphuretted hydrogen is likewise disengaged, except that the ignition is stronger *, When the union is effected in the atmosphere, a great in- flammation takes place, and sulphuret of potash is formed, The sulphuretted basis lkewise gradually becomes oxyge- nated by exposure to the air, and is finally converted into sulphate. The new substance produces some extraordinary and beau- tiful results with mercury. When one part of it is added to eight or ten parts of mercury in volume at 60° Fahrenheit, they instantly unite and form a substance exactly like mer- cury in colour, but which seems to have Jess coherence, for smal] portions of it appear as flattened spheres. Whena * The existence of hydrogen in sulphur, is rendered very probable by the ingenious researches of M. Berthollet Jun. Annales de Chimie, Fevrier 1807, page 143. The fact is almost demonstrated by an: experiment which I saw made by W.. Clayfield, esq., at Bristol, in 1799. Copper filings and pow- dered sulphur, in weight in the proportion of three to one, rendered very.’ dry, were heated together ina retort, connected with a mercurial pneumatic apparatus. At the moment of combination a quanuty of clastic fluid was li- berated amounting to nine or ten times the volume of the materials employed, and which consisted of sulphuretted hydrogen mixed with sulphureous acid. The first-mentioned product, there is every reason to believe, must-be re- ferred tothe sulphur, the last probably to the copper, which it is easy to conceive may have become slightly and superficially oxidated during the pro- cesses of filing and drying by heat. globule 00 16 On the Decomposition and Composition globule is made to touch a globule of mercury about twice as large, they combine with considerable heat; the com- poundsis fluid‘at the temperature of its formation; but when cool it appears as‘a solid metal, similar in colour to silver. If the quantity of the basis of potash is still further increased, so as to be about 5),th the weight of the mercury, the amal- gam increases in hardness, and becomes brittle. The solid amalgam, in which the basis is in the smallest proportion, seems to consist of about one part in. weight of basis and 70 parts of mercury, and is very soft and malleable. When these compounds are exposed to air, they rapidly absorh oxygen; potash which deliquesces is formed; and in a few minutes the mercury is found pure and unaltered. - When a globule of the amalgam is thrown into water, it rapidly decomposes it with a hissing noise; potash is form- ed, pure hydrogen disengaged, and the mercury remains free, The fluid amalgam of mercury and this substance seal all the metals I have exposed to it; and in this state of union, mercury acts on iron and aaa When the basis of potash is heated with gold, or silver, or copper, in aclose vessel of pure glass, it rapidly acts. upon them; and when the compounds are thrown into wa- ter, this fluid is decomposed, potash formed, and the metals appear to be separated unaltered. The basis of potash combines with fusible metals and forms an alloy with it; which has a higher point of fusion than the fusible metal. The action of the basis of potash upon the inflammable ~ oily compound bodies, confirms the other facts of the ue of its attraction for oxygen. On naphtha colourless and recently distilled, as I have s ready said, it has very little power of action ; but in naph- tha that has been exposed to the air it soon oxidates, and alkah is formed, which unites with the naphtha into-a brown soap that collects round the globule. On the concrete oils, (tallow, spermaceti, wax, for in- stance,) when heated, it acts slowly, coaly matter is depo- sited, of the fined Alkalis. — 17 sited, a little gas * is evolved, and a soap is formed; but in these cases it is necessary that a large quantity of the oil be employed. On the fluid fixed oils it produces the same effects, but, more slowly. if By heat likewise it rapidly decomposes the volatile oils; alkali is formed, a small quantity of gas is evolved, and charcoal is deposited. ; | When the basis of potash is thrown into camphor in fu- sion, the camphor soon becomes blackened, no gas is libe- rated in the process of decomposition, and a saponaceous compound is formed; which seems to show that camphor contains more-oxygen than the volatile oils. The basis of potash readily reduces metallic oxides when heated in contact with them. When a small quantity of the oxide of iron was heated with it, to a temperature ap- proaching its point of distillation, there was a vivid action ;° alkali and gray metallic particles, which dissolved with ef- fervescence in muriatic acid, appeared. The oxides of lead and the oxides of tin were revived still more rapidly; and when the basis of potash was in excess, an alloy was formed with the revived metal. In consequence of this property, the basis of potash rea- dily decomposes flint glass and green glass, by a gentle heat; alkali is immediately formed by oxygen from the oxides, which dissolves the glass, and a new surface is soon exposed to the agent. * When a globule of the basis of potash is introduced into any of the fixed oils heated, the first product is pure hydrogen, which arises from the de- composition of the water absorbed by the crust of potash during the expo- sure to the atmosphere. -The gas evolved, when the globule is freed from this crust, I have found to be carbonated hydrogen, requiring more than an equal bulk of oxygen gas for its complete saturation by explosior, I have made a great number of experiments, which it would be foreign to the ob- ject of this lecture to give in minute detail, on the agencies of the basis of potash‘on the oils. Some anomalies occurred which led to the inquiry, and the result was perfectly conclusive. Olive oil, oil of turpentine, and naph- tha, when decomposed by heat, exhibited as products different proportions of charcoal, heavy inflammable gas, empyreumatic oily matter, and water, so that the existence of oxygen in them was fully proved; and accurate ine dications of the proportions of their elements might be gained by their de- composition by the basis of potash. Naphtha of all furnished least water and tarbonic acid, and oil of turpentine the most, Vol, 32. No. 125, Oct. 1808. B At j 18 On the Nature of Alkalis and Earths. - Atared heat, even the purest glass is altered by ite basid . of potash: the oxygen in the alkali of the glass seems ta be divided between the two bases, the basis of potash and the alkaline basis in the glass, and‘ oxides, in the first degree of oxygenation, are the result. When the basis of potash is’ heated in tubes made of plate glass filled with the vapour of - - naphtha, it first acts upon the small quantity of the oxides of cobalt and manganese in the interior surface of the glass, and a portion of alkali is formed. As the heat approaches to redness, it begins to rise in vapour, and condenses in the colder parts of the tube; but at the point where the heat ig strongest, a part of the vapour seems to penetrate the glass, rendering it of a deep red brown colour; and by repeatedly distilling and heating the substance in a close tube of this kind, it Paci ice its metallic form, and a thick brown crust, which slowly decomposes water, and which com- bines with oxygen when exposed to air forming alkali, lines the interior of the tube, and in many parts is found pene- trating through its snbstance*. fn my first experiments on the distillation of ihe basis of potash, I had great difficulty in accounting for these phzeno- mena; but the knowledge of the substance it forms in its first degree of union with oxygen, afforded a satisfactory explanation. [Tobe continued. } ze a rn 4 II. On the Opinions that have prevailed respecting the Na- ture of Alkalis and Earths. By a Correspondent. To Mr. Tilloch. SIR, i HAVE not been a little poe by the matiner in which your correspondent O. begins his letter +. ‘© Messrs. Davy, Berzelius, and Pontin, have only verified _ * Thisis the obvious explanation i in the present state of our knowledge; but it is more than probable that the silex of the glass likewise suffers some change, and probably decomposition.” This subject I hope to’ be able to re- ‘sume on another occasion. i Phil. Mag. vol. xxxi. p. 2 what ° On the Nature of Alkalis and Earths. 19 what Lavoisier suspected, that the alkalis and earths are metallic oxides.” ) This ‘ only verifying”? seems to him a matter of very little importance, and the guess much more curious than the discovery. Reasoning in this way, it may be said, that Newton only verified what Seneca suspected, and that Co- lumbus had only rediscovered Plato’s Atalantis. From such a writer accuracy is not to be expected. His first assertion is incorrect. Lavoisier never supposed the fixed alkalis to be metallic oxides. In his time there were no analogies which led to such an opinion. This sagacious philosopher, on the contrary, has stated the idea that they may contain azote ; which QO. may see in the very book he. quotes, Kerr’s riya slatiGns of Layoisier’s Elements, second edition, page 213. Before Lavoisier, even as early as Van Helmont jun. and Beccher, it was conceived that metals were capable of being produced from earths. Bergman, in later times, but before Lavoisier, published the opinion with respect to barytes ; and Baron, with respect to alumine: but this kind of read- ing cannot be familiar to O., a person who seems to believe in the results of the experiments of Toudi and Ruprecht, on the metallization of the earths, and merely says, that their accuracy was called in question by Klaproth and Tihawski; whereas the fact is, that the metallic substances obtained by. Toudi and Ruprecht were proved by Tihawski and by Klap- roth to be phosphurets of iron: and the question was laid at rest by the elaborate researches of Savaresi, who showed that they could not be obtained except in cases when mate- rials which furnished phosphuret of iron were present. See Annales de Chimie, tome ix. p. 275, and tome x. p. 118. Mr. Kerr, in his Translation of Layoisier’s Elements, se- cond edition, has reasoned upon the experiments of Toudi and Ruprecht as if they were correct ; stating that if mag- nesia be a metallic oxide, then soda, being a modification ae magnesia, ‘‘ according to some experiments published in the Transactions of the Turin Academy,” must be also a metallic substance. He might have gone further, and said, that as M. Guyton de Morveau has proved potash to be B2 partly 20 On the Nature of Alkalis and Earths. - partly composed of lime, therefore potash contains a metallic oxide. But the experiments in which magnesia and lime have been said to be produced from the eed alkalis, have been shown to be incorrect by Darracq and others ; and the whole fabric falls to the ground. Mr. Kerr did not guess or predict any thing. He ae stated results considered by all. scientific chemists as mere delusions. { do not in the slightest degree mean to detract from the merit of Mr. Kerr as an excellent translator of Lavoisier. There is often ingenuity and good sense in his notes :—but in the conclusion of the passage, of which the beginning is quoted by O., as such an extraordinary instance of sagacity, this sentence occurs, “ Why should carbon, sulphur, and phosphorus, not be sonsidered as metals?—Because their specific gravity, lustre, and ductility, differ from the bodiés called metals, which differ so much in these particulars amongst themselves,’’—a mode of reasoning that would confound all principles of classification. What O, says about oxygen and hydrogen being the ultimate constituents of matter, is such vague declamation that your sober readers will not wish to read any comments ent. The dynamic philosophy of a new German school is. much more sublime, and more probable: that water + electricity is oxygen, and water — electricity hydrogen ; and that the metals are water + magnetism. Mere speculation can never do any harm, and is a toy’ with which any person has a right to amuse himself; but there is something in O.’s letter which may do harm. I mean the indecorous manner in which he speaks of the ob- jections of an English professor of respectability to the con- clusions of M. Braconnot. ee In reading these objections, they appear to me expressed ‘in a most gentle way, and merely calculated to modify the improper confidence which» some persons, little acquainted: with experimental chemistry, had placed in these researches. That all things may be composed of light, water, and air, is not-an assertion to be admitted on slight proof, or to be implicitly confided in, in consequence of, a single labour. Crell is atleast as high an authority as Braconnot, and yet. * his a e ‘ On the Nature of Alkalis and Earths. -: 21 his experiments on this subject have always been considered fallacious by the most enlightened chemists. thers ancl The general style of O.’s communication shows merely that he is little rejoiced at the progress of science, and that he wishes to diminish the importance of the late discoveries. He might have praised Mr. Kerr as much as he pleased, and no one would have been offended ; but every philosophical ‘man must be displeased at his rude and illiberal mention of a chemist, whose merit (being of a totally different nature) cannot possibly come in competition with that of Mr. Kerr. Your love of genuine science and your candour are such that I am surprised you should have permitted such un- worthy criticisms as those contained in the last. part of O.’s letter to pollute your pages. I can only attribute it to their having escaped your notice. Your Philosopbical Magazine has served, and I hope in future will serve, a nobler pur- pose than that of affording a cloak under which a masked bravo in science may hide a dager for the purpose. of wounding the feelings, and detracting, from the merit, of ” philosophical men. Iam, sir, respectfully, your obedient humble servant, October 4, 1808. Aw EXPERIMENTER. *,* « An ExpERIMENTER” has mistaken entirely the motive which induced us to give a place to’ the uncandid communication, under the signature O. Had we refused to publish it, insinuations of its pretended importance, and of our partiality, might have been the consequence. This we have before experienced. We thought it better, therefore, to allow the author to present his own statement of alleged facts—facts which we meant to have exposed in our present Number*, convinced that the more the subject is investia - gated, the greater will be the honour resulting to the exclu- sive discoverer, Mr. Davy. Mr. Davy’s modesty and merit, we cannot help also obserying, ought to have shielded him from what we consider as a wanton attack, made upon him by certain Northern reviewers. Would it be just to estimate * The remarks we meant to have offered are rendered unnecessary by the more able exposition with which “‘ An Experimenter” has furnished us, and for which we beg he will accept our best thanks, 3 - Bs their 22 Description of a new Compensation Pendulum. their merits as critics, by contrasting their lucubrations with the sublime discoveries of sir Isaac Newton? Or has the science of optics a more intimate alliance with chemistry than with criticism? When an individual arrogantly invites comparisons, he deserves to be humbled ; but to drag an un- assuming, unoffending ]abourer in any science, into contrast _ with a.luminary in another science, for the purpose of degra- dation, is, to say the least of it, an act of wanton cruelty, — and savours more of enyy than of sound criticism. Epir. III. Description of a new Compensation Pendulum. By Mr. H. Warp, of Blandford, Dorsetshire*, ‘Reference to the Engraving. Plate TI, : Fig. 2,73, 4, 5. ; Fre. 9. is a side view of the pendulum rod when to- gether. Ahiz are two flat rods or bars of iron, about an eighth of an inch thick. &2 is a bar of zinc interposed be- tween them, and is nearly a quarter of an inch thick. The corners of the iron bars are bevelled off, that they may meet with less resistance from the air; and it likewise gives them a much lighter appearance, These bars are kept together by means of three screws 11], which pass through oblong holes in hh and kk, and screw into 27. The bar Ah is con- nected to the one kk by the screw m, which I cal] the ad- justing screw. This screw is tapped into hh, and passes barely through £2; but that part of the screw which enters kk has its threads turned off. The bar 72 has a shoulder at its upper end turned at right angles, and bears at the top of the zinc bar & k, and is supported by it. It is necessary to have several holes for the screw m in order to adjust the compensation. See Fig. 1,6.—Fig. 3, 4, 5. are a side view of each bar separately. Fig. 6. shows the flat side of the zinc bar. Fig. 1. is 4 front view of the pendulum-rod when screwed together. The letters have the same reference to the different figures. * From Transactions of the Society for the Encouragement of Arts, Manu- factures, and Commerce, for 1807; but with corrections communicated by — the author The silver medal of the Society was voted to Mr. Ward for this invention. Now Description of a new Compensation Pendulum. 23 Now it is evident, that if any degree of heat or cold be applied to this compound rod, the one of zinc expands and-contracts as much as the two iron ones together; the distance from the point of suspension to the centre of oscil- Jation must remain the same. Oa In proportioning the length of the bars, I made use of Mr. Smeaton’s table of expansion of metals in the 48th vol. of Philosophical Transactions ; where he shows, by experi- ments made with a pyrometer, that the expansion of iron is to that of unhammered zinc, with the same degree of heat, as 151 to 353, and to that of zinc hammered, half an inch per foot, as 151 to 373. This great expanding property of zine renders it in theory extremely fit for the purpose of compensation in a pendulum, and I was desirous of know- ing if it would answer in practice, and likewise the exact proportion that was requisite to answer the intended purpose. I made two regulators whose pendulums were composed of iron and zinc, as above described, with this difference, however, that one had a detached escapement of a particular construction ; the zinc bar was not hammered, the ball of a | lenticular form, and weighed twenty pounds, its arc of vi- bration nearly five degrees. . The other had a simple remon- toir escapement, the zine bar was hammered half an inch per foot, the ball, of spherical form, weighed forty-six pounds, and vibrated two degrees and three quarters. These regulators were both placed in the same room, and their cases firmly fixed to the wall; the pendulums were ‘suspended from a stout brass cock, screwed to the back of their respective cases. In the inside of each case, and im- mediately behind the pendulum: rod, was hung a thermo- meter, for the purpose of comparing the degrees of heat. I adjusted them to mean time nearly by corresponding alti- tudes of the sun. After having compared them together for several days, I found that the one which had the ham- mered zinc bar went somewhat faster when the air of the room was heated by a fire in the grate than the other did. Hence I concluded that the difference of expansion of ham- mered and unhammered zinc was greater than Mr. Smeaton made it, at least it appeared so in this instance, Ba4 But . oe: ‘ Bi 5 24 Description of anew Compensation Pendulums - But to determine whether the length of the hammered. zinc bar was accurately proportioned to that of the iron ones, I wished next to prove, without waiting that length of time that Nature would require to produce a ssiaeienk alteration. in the temperature of the air, I proceeded to make the fol-. lowing experiment: I caused to be made a tin tube six feet long, and two inches and a half diameter at its larger end, from whence it gradually tapered to the other, which. was, only half.an inch diameter. Within the case, and as far fromy the pendulum as possible, I placed this tube ; the smaller end was carried through a hole in the top of the case, and projected a few inches above it. In the lower end of the tube was inserted the nozzle of a lamp, and immediately, under it, in tne bottom of the case, was a hole of an inch diameter to supply the lamp with air. By this means the ~ tube would communicate as much heat to the internal air, as to raise the thermometer about thirty-five degrees. Previous to the lamp being put in the case, J made both pendulums vibrate exactly together; and after an interval of - twenty-four hours, the one with the hammered zinc har. had gained, as near as I could judge, one tenth of a second. The mean height of the thermometer was fifty-three de- grees. I now lighted the laimp, and in about four hours every part appeared to be thoroughly heated, and the ther- mometer arrived at its maximum, which was eighty-eight degrees; at this point it continued with little variation. » While the heat was increasing I found the motion of the pendulum was accelerated. 1 again made them beat exactly together, aud in about ten hours after, the heated pendulum had gained one second; the thermometer in the other case continuing nearly the same. The lamp was then taken’ out, and as soon as the parts were cooled, and both thermome- ters showed the same degree, I adjusted the beat of the pen- dulums as before, and at the end of twenty- -four hours I found the pendulum that had been heated kept precisely the same rate as it did before the experiment was made. By this experiment it appeared evident that the zinc bar was considerably too long. The pendulum was then taken Oe, to haye more holes made for the adjusting screw ; and i] Description of a new Compensation Pendulum. 25 and after many. repeated trials with the lamp and tube, as before, I found the length of the zinc bar to be 22 inches, and consequently the length of the iron ones together 39:2 plus 22 equal to 61°2 inches, or, the expansion and con- traction of iron to that of zinc hammered, half an inch per foot, as 151 to 420. ave Having thus far satisfied myself with the hammered zine bar, I proceeded to make sumilar trials with the one that was unhammered: in doing which a circumstance occurred that I cannot account for, that when the air in the case was ra- refied by means of the lamp and tube, the arc of vibration would be about half a degree less than it was before the lamp was applied, which is directly contrary to what I should ex- pect would haye taken place. I afterwards found that the other pendulum was affected the same way, but in an ex- treme small degree, which, without doubt, was in conses quence of the ball being much heavier, and vibrating a ‘smaller arc,’ In taking the rate of the clock when the lamp was in the case, I at first computed from theory the error that would arise by such a diminution of the arc, and al- lowed for it accordingly ; but doubting whether the unlock- ing of the swing wheel might not, from a decrease of ve- Jocity in the pendulum, have a greater tendency to retard its vibrations, I therefore thought the experiment would be rendered more accurate if the maintaining power was in- creased until the are of vibration should be the same. After _ several trials | found the length of the unhammered zine bar to be about twenty-nine inches, which agrees pretty nearly with Mr. Smeaton’s experiment; that is, in regard to the relative expansion of iron and unhammered zinc. The zinc bar of the pendulum, which I here send to the Society of Arts, was hammered three quarters of an inch per foot; and by making experiments with it as I had done with sich other two, I fora the length of ‘it to be twenty- two inches, which is exactly the same length as the one that was hammered half an inch per foot, so that j it Seems nothing is “gained after hammering it toa certain degree; but I can- not think that any palencauthe laid distal to es us to judge of the degree of expansion that will take place with a determinate 26 Description of a new Compensation Pendulum. determinate increase of heat, from the quantity that is ex= - tended by the hammers much depends. on the degree of curvature and polish of the stake and hammer, and probably on the heating of the bar at the time; for it is necessary to heat it a litle hotter than boiling water, otherwise it will erack in hammering. ; In all these experiments it is to be understood that the ball of the pendulum was suspended by its centre ; but if ‘the ball be made to rest on its lower edge, the expansion and contraction of it must be taken into consideration. It has been the opinion of some mechanists that zinc is an unfit substance for a compensation pendulum, because they have thought it too soft for the purpose, and that after being heated or cooled to a considerable degree, it does not return to its original dimensions. If that was really the case, no doubt but it would be a general one, common to all me- tals in a greater or less degree; ‘but from the experiments and observations. I have-made on zinc pendulums, | am fully satisfied there is no. foundation whatever for such an opi- nion. Some time in the latter part of last simmer, I how- ever noticed a circumstance that made me doubt the matter —for when J first used any zine pendulum, I could never bring the clock to keep the same rate two days together, but it was continually retarded, whether I used the Jamp or not ; and had I not before observed a similar effect on a lever pendulum that was made of brass and steel, I should | have ascribed the cause wholly to the softness of the zinc bar; but by constantly comparing its daily rate with one that had been going a longer time, I found this retarding property gradually wore off, and mn less than a month would become quite settled to the rate that it would afterwards keep. By subsequent experiments with the lamp too, 1 have constantly found that all the pendulums I have hi- therto tried kept precisely the same rate, both during the time they were heated (provided they were properly adjusted) and afterwards, as they had done before. The cause of this ‘retardation appears to me to be, that the pomts of contact ef the different pieces, which compose the pendulum, are more closely connected after a little time than they are at first, Description of anew Compensation Pendulum. 95 first, that is, those points of contact do, by the weight of the ball, yield to each other in a small degree, until they get a broader bearing. ‘The advantages of this pendulum are, Ist, That from its simplicity it will never fail to have the desired effect. odly, That no extraordinary careis requisite inexecutingit. 3dly, That the compensation may be increased or diminished with the greatest ease, without stopping the clock more than a minute, by making fast one of the screws that keep the rods together whilst the adjusting screw is removing, taking care to release it again afterwards. And 4thly, That it can be manufactured for less expense than any other compensation pendulum hitherto published. N.B. The compensation of this pendulum which I now send to the Society of Arts is properly adjusted, at least very near the truth. The holes for the adjusting screw are made at such a distance from each other, that by removing the screw one hole, it will produce an alteration in the going of the clock about a quarter of a second per day with a ennee of thirty degrees of Fahrenheit’s thermometer, SIR, _PERMIT me to state to you the observations I have made since my compensation-pendulum was laid before the So- ciety. The regulator, with the hammered zinc bar, and ball of forty-six pounds weight, was firmly fixed to a brick wall at the top of my house. The adjustment of the length of the bars, by means of a lamp, was repeated as before. There was, however, an alteration necessary to be noticed; the ball of the pendulum rested on its lower extremity, instead of being suspended by its centre. J prefer this method, as being less liable to error if the rods should be sooner affected by heat or cold than the ball. The length of the zinc bar, as ascertained by the lamp, was now found to be 20 inches _and a quarter. The clock was then set to mean nes and suffered to go without alteration; the result is exhibited in the following table. 1806. 28 — Description of a new Compensation Pendulum. Error of clock Number of days Bi 1806 at time of ob- betweenthe ob- | Daily rate. . servation.. servation. Se | Sieh March 21 G0 - Fe oaosga ae April 8. Fast 92°8 bs sia ae: May 10 Slow 8:7 x Sal ae 26 BORE Uae s 16 -— 0°80. 26 — 110 June 21 — 500 | | Increased the compensation for heat and‘ cold 6 holes equal to 4 inches and 3 quarters; or, the length of the zinc bar 25 inches. The clock was again set to mean time, * { S. Se July : vse 26 Loss 0:36 27 Slow \ 9°3 ; 13 —_ O°a1 Aug. 9 — 12:0 7 Me i 16 — 14:2 98 2th lis Sept. 13 ——. 240 12 eda 25 nay 3; 9 992 sha 0°84 Oct. 17 — 52:1 : Althoneh a thermometer was attached to the clock, I could not, from a necessary attendance to business, register it regularly. The difference of its height in March and June may be taken at about 22 degrees, and in July and etoeee 14 degrees, without much error. On comparing it with the rate of the clock, the compen- sation, in the latter case, appears nearly as much too great, “as it was.in the first too small. The true length of the zine bar ought to be about 23 inches. The ‘Tength of the zinc bar, thus ascertained, is one inch and three quarters more than the experiment by the lamp makes it: indeed, I have always suspected there might be some error in that experiment, on account of the length of the arc of vibration being affected by it. Having no means of finding the time accurately but by equal altitudes, I could not get so many observations as ‘might be wished. I trust, however, these will not be found altogether useless. I am, sir, your obedient servant, HENRY tae, Blandford, October 21, 1806. To C. Taytor, M.D. Sec. oo ; A Re- 7 ‘ _ Description of a new Compensation Pendulum. 29 A Register of the going of the c'ock with the unbammered zinc bar twenty-nine inches in length, determined from observations of the sun’s transit over the meridian. Error of clock at time of ob- . Daily rate. servation. 5 1807. Mm. S. April 12 Slow 0 1 . fe cou, aes oer a cee ee May 1 — 010 xe June. 8 at La ‘ 20. Clock stopped, having been forgot to be wound up. It was set going again. ~ July 2 Slow 0 6 is * 5 Oye72 Me a Din aqkast HO}. co ice 18 — o14 ae 24 — 0 24 RE as Aug. 1 — 0 42 END linha oh 16 — 113 is Sept. 16 — 213 ea Oct. gai — 315 ao Noy. 2 —— 3 40 AG a ane 13 — 3 58 ROR (eee 26 — 4 8 CERI aie 1808. Jan. 1 —— 4 23 24. Clock stopped, swing to a fault in the escapement. It was afterwards altered. February 16, set going again. March 5 Fast 0 19 ay Ps 0 28 oie April 10 —— 0 36 i o7 17 —— O04! Ges 18 a 5 3°9 30 Sao 1 19 “« " 4°g 43 Jane), 26 — i151 - ei July 3 — 1 59 ive Aug. 4 a aD eh wept. ik —— 3 10 oy 14 — 3 24 N.8. This register has been made since the foregoing 3ccount was sent to the Society. y IV. Me- feto] _ IV. Memoirs of the late Erasmus Darwix, M. D. {Continued from vol, xxxi, p. 309.] ’ ' o (xe DARWINIANA,. His account, and mode of cure in defective ossification, rickets, distortion of the spine, lameness from the hip-boney and protuberance of the spine, claim every attention.. Innutritio ossium.. Innutrition of the bones.—Not only — the blood effused in vibices and petechia, or from bruises, as well as the blood and new vessels in inflamed parts, are reabsorbed by the increased action of the lymphatics; but. the harder materials, which constitute the fangs of the first - set of teeth, and the ends of exfoliating bones, and some- times the matter ot chalk-stones in the gout, the coagulable lymph, which is deposited on the lungs, or on the musclea after inflammation of those parts, and which frequently produces difficulty of breathing, and the pains of chronic rheumatism, and lastly the earthy part of the living bones are dissolved and absorbed by the increased actions of this system of vessels. The earthy part of bones in this disease of the innutrition of them seems to suffer a solution and reabsorption ; while the secerning vessels do not supply a sufficient quantity of calcareous earth aud phosphoric acid, which constitute the substance of hones. As calcareous earth abounds every where, Is the want of phosphoric acid the remote cause ? One cause of this malady is given in the Philosophical Trans- actions, where the patient had been accustomed to drink large quantities of vinegar. Two cases are described by Mr. Gouch. In one case, which I saw, a considerable quantity of calcareous earth, and afterwards of bone-ashes, and of decoction of madder, and also of sublimate of mercury, were . given without effect. All the bones became soft, many of. them broke, and the patient seemed to die from the want of being able to distend her chest owing to the softness of the ribs. M.M. Salt of urine, cailed sal microcosmicum, phos- phorated soda. Calcined hartshorn. Bone-ashes. Hard or petrifying water, as that of Matlock, or such as is found i in 3 3 all Memoirs of Erasmus Darwin, M.D. 31 ail limestone or marley countries. The calcareous earth in’ these waters might possibly be carried to the bones, as mad- der is known to colour them. Warm bath. Volatile or fixed alkali as a lotion on the spine, or essential oils. _ The innutrition of the bones is often first to be perceived by. the difficulty of breathing and palpitation of the heart on walking a little faster than usual, which I suppose is owingto the Eotenecs of the ends of the ribs adjoining to the sternum 5 on which account they do not perfectly distend the chest, when they are raised by the pectoral and intercostal muscles with greater force than usual. After this the spine becomes curved both by the softness of its vertebrae, and for the pur- pose of making room for the disturbed heart. As these patients are pale and weak, there would seem to be a deficiency of oxygen in their blood, and in conse- quence a deficiency of phosphoric acid; which is probably produced by oxygen in the act of respiration. Bes Mr. Bonhomme in the Chemical Annals, August 1793, supposes the rickets to arise from the prevalence of vege- » table or acetous acid, which is known to soften bones out of the body. Mr. Dettaen seems to have espoused a similar opinion; and both of them in consequence give alkalis and: testacea. Ifthis theory was just, the soft bones of such patients should shew evident marks of such acidity after death ; which I believe has not been observed. Nor is it analogous to other animal facts, that nutritious fluids se- ereted by the finest vessels of the body should be so little animalized as to retain acetous or vegetable acidity. The success attending the following case in so short a time as a fortnight, I ascribed principally to the use of the warm bath, in which the patient continued for full halfan hour every night, in the degree of heat which was most _ grateful to her sensation, which might be I suppose about 94. Miss , about ten years of age, and very tall and thin, bas laboured under palpitation of her heart, and diffi- cult breathing on the least exercise, with occasional violent dry cough, for a year or more, with dry lips, httle appetite either for food or drink, and dry skin, with cold extremities. She has at times becn occasionally worse, and been relieved in 32 Memoirs of Erasmus Darwin, M.D. in some degree by the bark. She began to bend forwards; and to lift up her shoulders. The former seemed owing to ~_a beginning curvature of the spine, the latter was probably caused to facilitate her difficult respiration. M. M. She used the warm bath, as above related ; wh ch by its warmth might increase the irritability of the sinallees series of vessels, and by supplying more moisture to the blood might probably tend to carry further the materials which form calcareous or bony particles, or to convey them in more dilute solution. She took twice a day twenty grains of extract of bark, twenty grains of soda phosphorata, and ten grains of chalk, and ten of calcined hartshorn, mixed into a sees with ten drops of laudanum ; with flesh food both to dinner and supper ; and Port wine and water instead of the. small beer she had been accustomed to; she lay on.a sofa frequently ina day, and occasionally used a neck-swing. Rachitis. Rickets.—The head 1s large, protuberant chiefly on the forepart. The smaller joints are swelled; the ribs depressed ; the belly tumid, with other parts emaciated, This disease from the innutrition or softness of the bones - arose about two centuries ago; seems to have been half a century in an increasing or spreading state ; continued about balf a century at its height, or greatest diffusion; and is now nearly vanished ; which gives reason to hope, that the smallpox, measles, and venereal disease, which are all of modern production, and have already become milder, may in process of time vanish from the earth, and perhaps be succeeded by new ones! Spine distortio. Distortion of the spine is another disease originating from the innutrition or softness of the bones. “I once saw achild about six years old with palpitation of heart and quickness of respiration, which began to have a curva~- ture of the spine; I then doubted, whether the palpitation . and quick respiration were the cause or consequence of the curvature of the spine; suspecting either that Nature had bent the spine outwards to give room to the enlarged heart, or that the malformation of the chest had compressed and impeded the movements of the heart. But a few weeks ago, on attending a young lady about ten years old, whose spine had, Memoirs of Erasmus Darwin, M.D. 33 had lately begun to be-distorted, with very great difficulty and quickness. of. respiration, and alarming palpitation, of the heart, I convinced myself, that the palpitation and difficult respiration were the effect of the change of the ca- vity of the chest from the distortion of the spine; and'that the whole was therefore a disease of the innutrition or soft- ness of the bones. - For on directing her to lie down much in the day, and to take the bark, the distortion became less, and the palpi- tation and quick respiration became less at the same time.) After this observation a neck-swing was directed, and she took the bark, madder, and bone-ashes ; and she continues; to amend both in her shape and health. LP ai _ Delicate young ladies are very lable to become awry. a many boarding-schools. This is occasioned principally by, their being obliged too long to preserve an erect attitude, by sitting on forms many hours together. To, prevent-this the school-seats should haye either backs, on which they. may occasionally rest themselves ; or desks before them, on, which they may occasionally a This is a thing of greater. consequence than may appear to those who ave not /at- tended to it. et - When the least tendency to become awry is Boda they should be advised to lie down on a bed or sofa for at hour in the middle of the day for many months; which generally prevents the increase of this deformity by taking, off for a time the pressure on the spine of the’ back, and it at the same time tends to make them grow taller. Young, persons, when nicely measured, are found to be half an inch higher in a morning than at night; as is well known to those who enlist very young men for soldiers. This is, owing to the cartilages between the bones of the back’ be-, coming compressed i the weight of the head and shoulders. on them during the day. It is the same pressure which produces curvatures and distortions of the spine in growing children, where the bones are softer than usual ; and which. may thus be relieved by an horizontal posture for an hour, it the middle of the day, or by being frequently allowed to; jean'on a chair, or to play on the ground ona carpet. Vol. 32. No. 125, Oct. 1808, C Young 2 a ae $4. Memoirs of Erasmus Darwin, M.D. Young ladies should algo be directed, where two sleep in abed, to change every night, or evety week, their sides of the bed; which will ‘prevent their tendency to sleep al- ways on the samé side; which is not only lable to, produce crookedness, but’also to occasion. diseases by the internal parts being so long kept in uniform contact as to grow to- gether. For the same reason they should not be allowed: to sit'always on the same side of ‘the fire or window, because they will then be inclined too frequently to bend themselves to ‘one side. ‘Another great cause of injury to the shape of young ladies is from the pressure of stays, or other tight bandages, which at the same time cause other diseases by changing the form of situation of the internal parts. Ifa hard part of the stays, even a knot of the thread, with which they are sewed*to=! gether, fs pressed hard’ upon one side more than ‘the other, the child bends from the side most painful; and thus occa- si6ns a curvature of the spine. To counteract-this effect, stich stays as have fewest hard parts, and especially such as ¢an'be daily or weekly turned, are preferable to others. Where frequent lying down on a sofa in the day-time, and swinging frequently for a short time by the hands or head} with loose dress, do not relieve a beginning distortion of the back, recourse may be had toa chair with stuffed) moveable arms for the purpose of suspending the weight of ihe body by cushions under the arm-pits, hke resting on crutches, or like the leading-strings of infants, Fron the top of the back of the same chair a roabved steel bar'may also project to suspend the body occasionally, or in part. by the head, dike the swing above’ mentioned. The use of this chair is more efficacious in straightening the spine, than simply lying down horizontally ; as it not only takes off the: — pressure of the head and shoulders from the spine, but at the same time the inferior parts of the body. contribute to: draw the spine straight by their weight; or lastly, recourse’ may be had to a spinal machine first described in the Me- thoirs of the Academy of Surgery in Paris, vol. ii. p. ee by M. Le Vacher, and since made by Mr. Jones, at No. 6. North- street, Tottenham-court Road, London, which ‘aie ¥ pends _ Memoirs of Erasmus Darwin, M.D. 35 pends the head, and placés the weight of it on the hips. This machine is capable of improvement by joints in the bar at the back of it, to permit the body to bend forwards with- out diminishing the extension of the spine. ‘The ebretiius to this machine of M. Vacher, which is made by-Mr. Jones, are, first, that it 1s worn in the day- time, and has a very unsightly appearance. Mr. Jones bas endeavoured to remedy this, by taking away the curved: bar over the head, and substituting in its place a forked bar, risjng up behind each ear, with webs fastened to it, which pass-under the chin and occiput. But this is not an im- provement, but a deterioration of M. Vacher’s machine, as it prevents the head from turning with facility to either side. Another objection is, that its being worn when the mus- cles of the back are in action, it is rather calculated to pre- - vent the curvature of the spine from becoming greater, than to extend the spine, and diminish its curvature. : For this latter purpose I have made a stecl bow, which | receives the head longitudinally from the forehead to thé occiput ; having a bore. furnished with a web to sustain the chin, and another to sustain the occiput. The summit of the bow is fixed bya swivel to the board going behind the head of the bed above the pillow. The bed is to be inclined from the head to the feet about twelve or sixteen inches. Hence the patient would be constantly sliding down during sleep, unless supported by this bow, with webbed forks, covered also with fur, placed beneath the chin, and beneath the occiput. There are also proper ' webs lined with fur for the hands to take hold of oceca- sionally, and also to go under the arms. By these means I should hope great Hivaneee from gradually extending the spine during the inactivity of the muscles of the hace. is and that it may be done without disturbing the sleep of the patient; and if this should happen, the bow is made to open by a joint at the summit of it, so as to be in- stantly disengaged from the neck by the hand of the wearer, This bow I have not yet had opportunity to make use of, but it may be had from Mr. Harrison, whitesmith, Bridge-_ gate, Derby. - } ; C2 : it 86 Memoirs of Erasmus Darwin, M.D. It will be from hence easily perceived, that all other mes thods of confining or directing the growth of young people should be used ae great skill; such as back-boards, or bandages, or stocks for the feet; and that their application should not be continued too long at a time, lest worse con~ sequences should ensue than the deformity they were de- signed to remove. To this may be added, that the stiff erect attitude taught by some modern dancing-masters does not contribute to the grace of the person, but rather militates Against it ; as is well seen in one of the prints in Hogarth’s Analysis of Beauty ; and is exemplified by the easy grace of some of the ancient statues, as of the Venus de Medici, and the Antinoiis, and in the works of some modern artists, as in a beautiful print of Hebe feeding an eagle, painted by Hamilton, and engraved by Eeinton, and many of the fioures of Angelica Te Gena Where the Bone of one of the vertebra of the back has been swelled on both sides of it, so as to become. protnbe- nt, issues near the swelled part have been found of great service. This has induced me to propose in’ curvatures of the spine, to put an issue on the outside of the curve, where it could be certainly ascertained, as the bones on the convex side of the curve must be enlarged; in one case I thought this of service, and recommend the further trial of it. — In the tendency to curvature of the spine, whatever strengthens the general constitution is of service; as the use of the cold bath in the summer months. This, however, re« quires some restriction both in respect to the degree of cold- ness of the bath, the time of continuing 1n it, and the sea- son of the year. Common springs, which are of forty-eight, degrees of heat, are too cold for tender constitutions, whe- ther of children or adults, and frequently do them great and irreparable injury. The coldness of river water in the sum- - ner months, which is about sixty-eight degrees, or that, of Matlock, which is about sixty-eight, or of Buxton, which is eighty-two, are much to be preferred. The time of cons tinuing in the bath should be but a minute or two, or not. $0 39 long as to occasion a trembling of the limbs from cold. In i Memoirs of Erasmus Darwin, M.D. 37. In respect to the season of the year, delicate children should certainly only bathe im the summer months; as the going, frequently into the cold air in winter will answer all the pat poses of the cold bath. ; Claudicatio coxaria. Lameness‘of the hip: A nodding of the thizh bone is said to be produced in feeble children by the softness of the neck or upper part of that bone beneath, the cartilage; which is naturally bent, and in this. disease bends more downwards, or nods, by the pressure of the body, and thus renders one lez apparently shorter than the other. In other cases the end of the bone is protruded out of its socket, by inflammation or enlargement of the carti- Jages or ligaments of the joint, so that it rests on some part ‘of the edge of the acetabulum, which in time becomes filled up. When the legs are straight, as in standing erect, there is no yerticillary motion in the knee-joint; all the motion then in turning out the toes further than Nature designed, must be obtained by straining in some degree this head of the thigh-bone, or the heeutias or cavity, in which it movess. The has induced me to believe, that this misfortune of the nodding of the head by the bone, or partial dislocation of it, . by which one leg becomes shorter than the other, is somes _ times occasioned by making very young children stand in. what are called stocks; that 1s, with their heels together, and their toes quite out. Whence the socket of the thigh bone becomes inflamed and painful, or the neck of the bone is bent downward and outwards. In this case there is no expectation of recovering the straightness of the end of the bone: but these patients are liable to another misfortune, that is, to acquire after- wards a distortion of the spine; for as one leg is shorter than the other, they sink on that side, and in consequence bend the upper part of their bodies, as their shoulders, the contrary way, to balance themselves; and then again the neck is bent back again towards the lame side, to preserve the head perpendicular; and thus the figure becomes, quite distorted like the letter S, owing originally to the deficiency of the length of one limb. The only way to prevent this eurvature Of the spine is for the child to wear a high- -heeled C3 - shoe ¥ 38. | Memoirs of Erasmus Darwin, M.D. shoe or patten on the lame foot, so as to support that side on the same level with ‘the other, and thus to prevent a greater deformity. yi { T have this day seen a young lady, about twelve, who dees not limp or waddle in watking; but nevertheless, when she stands or sits, she sinks down towards her right side, and turns out that toe more than the other. Hence, both as she sits and stands, she bends her body to the right 5 ~ whence her head would hang a little over her right shoulder: ‘but to replace this perpendicalarly, she lifts up her left shoulder and contracts the muscles on that side of the neck ; which are therefore become thicker and stronger by their continued action ; but there is not yet ay very perceptible distortion of the spine. : As her right toe 1s turned outward rather more than na- tural, this shows the disease to be in the hip-joint; because, ~when the limb is stretched out, the toe cannot turn hort- zontally in the least without moving the end of the thigh bone; although when the knee ts bent, the toe can be turn- ed through one third or half of a circle by the rotation.of the tibia and fibula of the leg round each other. Hence if children are set in stocks with their heels touching each other as they sit, and are then made to rise up, till they — stand erect, the socket or head of the thigh bone becomes injured, especially in those children whose bones are soft ; and a shortness of that limb succeeds, either by the bend- ing of the neck of the thigh bone, or by its getting out of the acetabulum ; and a consequent rising of one shoulder | - anda curvature of the spine is produced from so distant a cause. M.M. An elastic cushion made of curled hair should be placed under the affected hip, whenever she sits; or should be fitted to the part by means of drawers, so that she cannot avoid sitting on it. A neck-swing, and lying down in the day, should be occasionally used to prevent or remove any curvature of the spine. Spina protuberans. Protuberant spine. One of the bones of the spine swells, and rises above the rest. This i iS not an ancommon disease, and belongs to the innutrition of the bones : On Oxalic Acid. 39 bones, as the bone must become soft before it swells; which softness is owing to defect of the secretion of phosphorated calcareous earth. The swelling of the bone compresses a part of the brain, called the spinal marrow, within the cavity of the back-bones; and in consequence the lower limbs be- come paralytic, attended sometimes with difficulty of empty- ing the bladder and rectum. M.M. Issues put on each side of the prominent hone ate ‘of great effect, I suppose, by their stimulus; which excites into action more of the sensorial powers of irritation and sensation, and thus gives greater activity to the vascular sy- stem in their vicinity. The methods recommended in distor- tion of the spine are also to be attended to. [To be continued. | V. On Oxalic Acid. By THomas Tuomson, M. D. F-R.S. Ed. Communicated 4 CHARLES, HarcHETt, Esq., F.R.S. {Concluded from vol. ei p- 253:] IV. Composition of Oxalic Acid. Tue knowledge of the relative weights of the elements which compose oxalic acid, though of importance, is not sufficient to convey a clear idea of this compound, and ih ‘what respect it differs from tartaric acid, alcohol, sugar, and various other bodies possessing very different properties, though composed of the very same elements in different pro- portions. It has been ascertained, by numerous and decisive expe- riments, that elementary bodies always enter into combina- tions in determinate proportions, which may be represented by numbers. For example, the numbers which correspond to the four elements, oxygen, azote, carbon, and hydrogen, are the following : Oxygen 6 _Azoie mh Carbon - ‘4'5 Hydrogen 1 C AL A Now, 40 ey On Oxalic Acid, Now, in all compounds consisting of these ingredients, thé proportion of the different constituents may always be re- presented by these numbers, or by multiples, of them; thus; the composition of the following substances may! be thus stated ; Oxygen. |Hydrogen. Water. - - 6 ae Carbonic oxide - hie a Carbonic acid - 2x 6} - 4 Carburetted hydrogen {| - -/ 2x1 Olefiant gas esp fe i 1 Nitrous gas - Gili = 2 Nitric acid ~ 2x 6]j - < {Nitrous oxide = Si sh Carbon. + 4°35 + 4°5 + 4°5 + 4°5 Azote, ° » at +5 + 2x5 - From the knowledge of this curious law, it is difficult to ‘avoid concluding that each of these elements consists ofatoms of determinate weight, which combine according to certain fixed proportions, and that the numbers above given repre- sent the relative weights of these atoms respectively. Thus, an atom of oxygen weighs six, an atom of hydrogen one, © &c. Water is composed of one atom of oxygen, and one atom of hydrogen; carbonic acid of two atoms of oxygen, and one of carbon, &c. This curious theory, which promises to throw an unexpected light on the obscurest parts of che- mistry, belongs to Mr. Dalton. I have elsewhere illustrated it at considerable Jength*. The same. law holds with respeet to the salts. and bases always combine in determinate proportions, We may affix numbers to all the acids and bases, which num- bers, or their multiples, will represent all the combinations into which these bodies enter. Some of these numbers are given in the following table : Sulphuric.acid. 33. Barytes. 67 Muriatic acid 18 Soda 24: Carbonic acid 16°5 ‘Lime 23 Nitric acid 17. Ammoma 6 * See System of Chemittry, Hi, 424, &c, 3d edition, The acid These On Oxalic Acid. Aq These numbers may be conceived to represent the relative weights of an integrant particle of each of these substances 5 formed on the supposition that an atom of hydrogen weighs 1. It follows equally from this law, that the aids and yates combine particle with particle, or a certain determinate num- ber of particles of the one with a particle of the other. One of the most important points in the investigation of compound bodies, is to ascertain the number which denotes the weight of an integrant particle of each of them, that of an atom of hydrogen being 1; because this number, ora multiple of it, represents the weight of each, which enters into all combinations ; and becatise it enables us to estimate the number of elementary atoms of which each is composed. From a careful comparison of the table of oxalates, given in a preceding part of this paper, with the weight of the diffe- rent bases already determined *, it appears that the weight of an integrant particle of oxalic acid must be represented by the number 39°5. | Now, what number ofatoms a oxygen, carbon, and hy- drogen, 20 to constitute an integrant particle of oxalic acid 3 We have assigned the relative. weights of each of these atoms, and we have ascertained the relative proportions of the respective elements of oxalic acid. From these data‘tt is - easy to solve the problem. An integrant particle of oxalic acid consists of nine atoms combined together, namely, four atoms of oxygen, three of carbon, and two of hydrogen. | 4 atoms of oxygen weigh 4x 6 = 24 3 atoms of carbon 3X 4°5.=.13°5 2 atoms of hydrogen Drea ined as O. Total 39°5 which together make up the weight of an integrant particle of oxalic acid. According to these proportions, 100 parts of oxalic acid is composed of * For these weights, and the method of determining them, I refer the reader to my System of Chemistry, 3d edition, iii. 619. The numbers which lbave there assigned are, 1 am persuaded, rather too low. Oxygen ~ a ie ae Oxygen- - 61 : Carbon. = 34 6 Hydrogen - 5 100. , ‘numbers which do not indeed exactly correspond with the result of the preceding analysis, but which approach suffi- ciently near it to give the reasoning employed considerable probability at least, if it does not lead to certainty. We may now examine the decomposition which takes place when oxalate of lime is exposed to heat. Let an atom of oxygen be w, an atom of carbon c, and an atom of hy- drogen h. An integrant particle of oxalic acid may be repre- sented-by 4w~ + 3c¢+2h. We may represent the com- position and weight of an integrant particle of each of the substances into which oxalic acid is decomposed by heat, — by the following symbols and numbers : Carbonic acid - 2w + cweight 16°5 Carburetted hydrogen Cs Ohi = ie 6b Carbonic oxide - wee - 105 Water - - wth ohne Charcoal - - c - 45 ’ . . . a.@ ! We may now conceive three particles of oxalic acid to be decomposed at once, and to’resolve themselves into these substances, in the following proportions: 4 particles of carbonic acid = Sw eae 2 particles of carburetted hydroven= - - 92c+4kh 2 particles of carbonic oxide =2w-+ 2¢ 2 particles of water == = =2w-- +29 “particle of charcoal. | - ll aes Me 7 | Total 12u~+9c+6k 3 particles of oxalic acid - =12w+o0c+6h We see that such a decomposition is possible. [t remains only therefore to see whether the weights of these substances, which result from this. hypothesis, correspond with the Ber eeding analysis. Now, 4 partidleg < & Gn Oxalic Acid. 43 4 particles of carbonie acid weigh 4 x 16°5 = 66 2 particles of carburetted hydrogen Die Xe! Gr Si ame Nee 2 particles of carbonic acid OX 1073) =o 8 2 particles of water - = Wal Caer fica emetlh ze* 1 particle of charcval = Aebi P45 Total 118°5 Reducing these proportions to 100 parts of acid, and joining eects the two inflammable gases, the numbers come out as follows: Carbonic acid 55°70 we actually obtained 59°5 Inflammable air 28°69 © - - - 24° m6 Water - 11°81 = - - 15k Charcoal - 3°80 = = - 4°68 100°00 100-00 It is impossible to expect exact correspondence between | the theory and hypothesis, till the numbers representing the. weights of the elementary atoms be ascertained with more rigid accuracy than has hitherto been done. I satisfied my- self with taking the nearest round numbers, which are suf- ficient at least to show an evident approximation to the pro- portions obtained by experiment. - “V. Composition of Sugar, and Formation of Oxalic Acids _ When a compound body is decomposed, and resolved into | a number of new substances, the products are almost always simpler, or consist of integrant:particles, composed of fewer atoms than,the integrant particles of the original body. Thus, though oxalic acid is composed of nine atoms, none of the products eyolved, when that acid is decomposed by heat, contain more than three atoms. Hence it is probable that - sugar is amore compound body than oxalic acid, because nitric acid resolves it into a variety of new compounds, one of which is oxalic acid. It may be worth while to examine the action of nitric acid on sugar, and the formation of xalic acid, more closely than has hitherto been done, as the investigation will furnish some data for estimating the com position of sugar. Two / ‘44 On Oxalic Acid. Two hundred grains of pure crystallized sugar being treated with diluted mitric acid in the usual way, yielded 200’ cubic inches of carbonic acid, 64 cubic inches of nitrous gas,. and 70 cubic inches of azotic gas. But these numbers, though the result of a good many experiments, are not to be considered as very exact. The uncertainty depends upon the property which the solution has of producing more gas after the sugar is decomposed, at the expense of the oxalic acid formed. Now, it is difficult to stop at the precise point. The whole weight of oxalic acid, which can be obtained from 200 grains of sugar, amounts to 116 grains. If the experiment be properly conducted, the whole of the sugar is decomposed, or at least the quantity of residuary matter is small. From the preceding statement, there 1s reason to conclude that 100 grains of sugar, when decomposed by nitric acid, yield,. : : : t Grains. 1. Oxalic acid crystals 58 grains, or real acid 45 2. Carbonic acid 100 cubic inches, equivalent to 46°5 while these are evolved obviously by the decomposition of the nitric acid. 1. Azotic gas 35 cubic inches equivalent to 10°62 2. Nitrous gas 32 cubic inches equivalent to 10°85 Now, as nitric acid contains no carbon, it is obvious that . the oxalic acid formed, and the carbonic acid evolved, must . contain the whole carbon contained in 100 grains of sugar. 7 \ Grains. 45 grains of oxalic acid contain of carbon 14:40 46°5 grains of carbonic acid contain of ditto 13-02 ed Total 27°42 therefore 100 grains of sugar contain 277 grains of carbon. The azotic gas and nitrous gas must have been originally in the state of nitric acid, and must have given out oxygem when they were evolved. But nitric acid is composed of - Oxygen. Azote ~ 10°62 + 25 Nitrous gas 10°85 + 4:5 20°5 Therefore On Oxalic Acid. 45 Theréfore they must have parted with 29°5 grains of oxy- gen. We are at liberty to suppose that the whole of this oxygen went to the formation of carbonic acid. Now, 46-5 grains of carbonic acid are composed of Grains. Oxygen 2 33:5 Carbon - - 13:0 46°5 From this it appears, that in the carbonic acid there were four grains of oxygen more than was furnished by the nitric acid. I confess I am disposed to ascribe this surplus to errors in the experiments, and to believe that the whole of the oxygen of the carbonic acid was furnished by the nitric acid. This being admitted, it follows that the carbon of the carbonic acid, and the whole constituents in the oxalic acid, were furnished by the sugar. These are as follows. Grains. Carbon - - - 27°5 Oxygen in 45 grains data acid 28°8 Hydrogen in ditto = 1°S 581 If this total be subtracted from the 100 grains of sugar used, there will be a remainder of 41-9 grains. As this quantity of the sugar has disappeared, and is no where to be found among the products, we must suppose that it has assumed the form of water. Now 41°9 grains of water are composed of Oxygen 359 Hydrogen 6 41°9 Adding thse quantities to the preceding products, we obtain the composition of sugar, as follows : Oxygen = 64°7 Carbon OS Hydrogen 7°8 100°0 eerwesen Though 46 On Oxalic Acid. Though the process of reasoning, which led to this ana- lysis of sugar, is too hypothetical to be trusted implicitly, yet I am Wersiiaded that it is to a certain degree correct, and that the result obtained does not deviate very far from the truth. If we compare Lavoisier’s statement of the compo- sition of sugar obtained in a different manner, though by a mode of reasoning not less hypothetical, we shall be surprised if at its near coincidence with mine. His numbers.are Oxygen - 64 Carbon 28 J Hydrogen 8 100 oa It is true that two different hypotheses may Jead to the same result, and yet be both wrong; but this becomes infinitely improbable in the present case, when we consider that the proportion of carbon, which I assign to sugar, must at all events be nearly correct. | We have no direct method of determining the weight of » anAntegrant particle of sugar; but if the accuracy of the preceding analysis be admitted, it furnishes us’ with an in- direct one, which cannot be rejected; for it is clear, that the atoms of oxygen, carbon, and hydrogen, will be to each other respectively, as the numbers 6+, 3%, 23; and these numbers reduced to their lowest terms become 5, 3, 4, nearly, which being primes with respect to each other, must represent the number of atoms of which an integrant par- ticle of sugar is composed. Sugar then is a compound of 12 atoms; namely, five of oxygen, three of carbon, and four of hydrogen ; the weight of an integrant particle of it is 47°5, andits symbol is 5w +3c+4h. It differs from oxalic acid merely in containing an additional atom of oxy- gen and two of hydrogen. If we had any method of re- moving these substances, without altering the proportion of the other constituents, we should obtain a much greater quantity of oxalic acid from sugar than we can -at present 5 but nitric acid acts by removing one-half of the carbon in the form of carbonic acid; the sugar deprived of this, re- solyes itself into oxalic acid and water. Suppose two par-— gee pee: ~~ ticles Memoir on the Incombustille Man, &c. AT ticles of sugar acted on at once, the symbol for them will be 10w+4+6¢4 8h. Let three atoms of the carbon be - removed by the action of the nitric acid, there will remain 10w 43c4+ 8h... Now- A particle of oxalic acid -=4w+3c+oh Six particles of water S—UGiqy: el) a6 & . lOw +3¢4 8h which is just the quantity of oxalic acid left. This will give us some idea of the way in which the formation of oxalic acid by nitric acid is accomplished. And although the series of changes is probably more complicated, yet they are ulti- mately equivalent to the preceding statement. T allude to the formation of malic acid, which is said to precede the oxalic acid, and afterwards to be converted into it by the subsequent action of nitric acid; but on the composition and formation of this latter acid, I avoid making any obser- vations at present, as I propose to nel ee ‘the subject of a separate dissertation. | a a ree Serer VI. Memoir on the Incombustible Man; or the pretended Phenomenon of Incombustibility.. Translated from the italian of Louis Sementini, M.D., chief Professor of. Chemistry inthe Royal University of Naples*. Preface. I HAVE undertaken this short treatise after performing se- _yeral experimenis in the presence of some of my learned — friends, on the pretended incombustibility. | Tt 1s extraordi- nary, that in examining all the phenomena which Seior Lionetto has exhibited to the public, no one has mentioned the most extraordinary of them, his proposal to enter an even, (I know not at what degree of Reaumur’s thermome- * For this curious memoir we are indebted to Dr. Wollaston, Sec. and F.R.S. We have frequently had cccasion to notice the performances of Senor Lionetto in our former volumes, but the above is the only scientific ~ account as aes published, ter,) 48 Memoir on the Incombustible Man ; ter,) with a piece of raw mutton in one hand and an egg! in the other, &c. But, if the phenomenon does tot éxist, what reproach should [ not merit for having bazarded an examination of an imaginary fact? Dr. Horstis fell into this error, in wishing to give a physical explanation of the golden tooth of the boy from Silesia, without first ascer- taining 1f the phenomenon really existed, or was the effect of illusion, as the fact was afterwards publicly known te be a deception. Now returning to. the proposal of the oven, without entering into any sublime theory, I can venture to assure any person whatever, that Lionetto never entered an oven, nor will he enter one near us: this I shall repeat till the very moment in which myself and others may see him enter it; so well persuaded am I that he cannot realize his proposal, if the oven has no particular construction which alters its nature and effects. There are indeed some instances of persons having ‘suffered the action of a very high tempe- rature for some time; but there is a great difference between a place simply Rested where the air had access, and. a close oven. DE FS a Of RE : “The arrival pale a man calling himself inenmbnaitel hi treated hot iron'in various manners, drank boiling oil, and handled liquid lead, &c., was scarcely announced, when this interesting phenomenon engaged me so much, that I left no means untried by which I might be enabled to form an opinion of it. First, it was indispensably necessary to ascertain the fact, by assisting assiduously at the experiments which Senor Lionetto, otherwise called the incombustible man, presented to the public. [| approached as near to him as possible, that I might observe minutely whatever was most particular in his experiments—of which the following is an account. Sefior Lionefto commenced the proof of his incbmbnstis bility by petting over his head a thin plate of red-hot iron; which, at least in appearance, did not alter his hair. The jron had scarcely come in contact with it, whena consider- able quantity of dense white vapour was seen to arise. . A second plate of red-hot iron was hkewise. passed-over the whole or the pretended Phenomenon of Incombustibility. Ag whole extent of his arm and leg. With another red-hot iron he struck his heel and the point of the foot repeatedly : in this experiment the contact of the fire was longer than in any of the preceding. From the sole of his foot so much yapour was disengaged, that being very near the experi- enter, my eyes and nose were sensibly affected. He also put between his teeth a heated iron, which, although not red-hot, was still capable of burning. It was announced that he had drunk half a glass of boiling oil; but, in fact, 1 found that he had never drunk such a dose, and that he had performed this twice by introducing a little into his mouth, not more than the third part of a spoonful, at a time. It was likewise said that he had washed his hands and face in boiling lead; but he now practised such an ex- periment only in rapidly bath.ng the extremities of his fingers in liquid lead, and also carrying a very small portion of it on his tongue. He afterwards passed a piece of red-hot iron over his tongue, without showing the least painful sensation. His tongue, which I was able distinctly to observe in this often-repeated experiment, was covered with a crust similar to what is seen on the tongues of persons in fevers; that is to say, it was covered with a kind of paste of a dirty gray colour. He exposed his foot again to the flame of burning oil, but kept it at a certain distance. In short, he threw sulphuric, nitric and muriatic acids on inflamed charcoal, and immediately exposed his face over the vapours which arose from those acids, keeping a small part of it in that situation. 7 The experiment with which Sefior Lionetto is accustomed to terminate his exhibition, 1s that of passing through the skin of his arma thick gold pin, which he does. without feeling the least pain. In this proof of his isensibility, I observed that the pin entered his skin with diificulty, re- quiring such a force as if it had to perforate dressed leather. Now although at first view this fact seemed to have no rela- tion with the others practised by means of fire, yet. it ap- peared to me to throw some light on the examination of the phenomena relating to the pretended incombustibility. From these experiments, which I have seen so often repeated, I fan- Vol. 32. No. 125. Oct. 1808. D cied 50 Memoir on the Incombustible Man ; cied that Sefior Lionetto’s skin had become so insensible;, from the effect of repeated frictions with some substances fit to produce such a change, by stimulating excessively the nerves and the vessels of the skin, and by recent usage, that it was capable of impeding in a certain degree the free- passage of caloric. Besides the action of such substances, T thought that the force of habit must always have added to, ‘such a disposition, and that even the frequent impression of the fire should have contributed not a little to produce such insensibility in his skim: the experiment of the pin which he put through it, was to me no light argument of its hebetude. : These opinions, however, were merely the effect of a system dictated by reason, and a knowledge of the, laws of animal life: but had J not known the means used to render the skin incombustible, nor had any other knowledge of the subject, I should not have been able to give a plausible expianation of the more surprising phenomena; such as the red-hot iron which he so often passed over his tongue with- out suffering any painful impression; and much less with such a system could I account for the boiling oil which he swallowed : neither could J imagine how he had prepared the internal surface of the cesophagus or of the stomach ; and in what manner he could suffer the action of almost red-hot iron, which he put between his teeth, on the enamel of which it is not possible to preserve any mixture. Instead therefore of uselessly wasting. time in simple: conjectures, I resolved to adopt the best experimental art. which I knew, trying on myself the action of all the means proper to benumb the cutaneous nerves, and to clothe the skin with a substance which was a:nonconductor of caloric. Few substances belonging to chemical compositions, or to other natural bodies, appeared to me proper for the -pur- pose which I had in view. The sharp sensation which was excited by the vapour disengaged by the contact of the fire with the incombustible membrane, and the chemical reason, induced me first to have recourse to acid substances, and to some of the acidulous salts. It would be too tedious to relate in detail all the various substances and experiments _ which» \ or the pretended Phenomenon of Incombustibility. 51 which I made: with some of them I attempted to rub my skin, which, after the liquids dried, was always sensible in the same degree to the action of the fire. The unfortunate result’ of my first experiments did not discourage me; persuaded that by the effect of only one rubbing, it was not possible to change the skin in sucha manner as to render it insensible to the action of fire. [I therefore repeated oftener on the same part. the frictions with the same substance, and perceived the effect, that it gradually became less and Jess sensible to the action of ca- loric. On one part of my body I repeated the frictions so often with dilute (allungato) sulphurous acid, that I was finally able to pass a plate of red-hot iron over it without any injury. TI afterwards discovered that dilute sulphuric, nitric, and muniatic acids would equally produce the same effect: but the sulphurous acid is preferable to all the others, as it produces the speediest and most, certain effect. I next tried the action of acidulous sulphat of alumine and potash, or the alum of commerce, a substance distinguished - for its property of preserving bodies from the action of fire. Jn making a saturated solution of this salt, I discovered how much greater styptic powers it had acquired by being sirongly apitheed or boiled (lollirte sulla spugna*). With ‘the Auid thus prepared, I rubbed one part of my arm several times, and did not before obtain such decided results; so that I have ever since used this solution. These essays, however, were only the rudiments of a know- ledge.of the phenomenon, the examination of which was still incomplete. An accidental combination afterwards in- duced me to undertake a new series of experiments, by which I might be enabled to give a more clear explanation of all the more difficult ‘operations executed by Lione‘to. Wishing to examine if washing the almost incombustible part would make it lose the quality it had acquired, I rnb- “bed it with hard’ soap, washed and dried it with a cloth, and applied the same plate of red-hot iron. I then dis- covered, to my surprise, that the skin of that part not only * Does the author mean Lurnt alum, i.e. alum boiled per se on an iron shoyel without water ? D2 preserved 52 Memoir on the Incombustible Man : preserved the same insensibility to the action of red-hot irott, but had even become stronger than at first. I again rubbed the same part with soap without wiping it with the cloth, and passed over it the iron very red-hot, without feeling any _ painful sensation, or even having the hair burned. Re- membering the crust which I observed on Lionetto’s tongues I determined to rub mine with the same soap; in conse- ” quence of which ‘it became equally insensible to the action of fire. I began with pieces of iron slightly heated, raising them gradually tll they were perfectly red-hot. I made a soft paste of soap triturated in a mortar, and water saturated with acidulous sulphat of alumine and potash (alum), agi- tated or boiled as above; and spreading this composition on my tongue, the experiment succeeded completely. Still more simple I found the process of first bathing the tongue - with sulphurous acid, and afterwards rubbing it often with a piece of soap. The experiment succeeded still better if after bathing the tongue with this acid, I covered it with a thin stratum of sugar reduced to impalpable powder, and rubbed it afterwards with the soap in the same manner. The sugar in this case, like a mordant, made a greater quantity of soap attach to the tongue, and adhere more solidly. By this mode of operating, the solution of alum, or of di- ' lute sulphurous acid, may be adopted at pleasure to benumb the nerves of the tongue, and the soap is a most efficacious means of obstructing (rifrangere) the action of caloric, the propagation of which it almost perfectly impedes. Of all the known substances, indeed, soap is that which of all others best merits the name of restrainer of caloric, as I shall show on another occasion. From these experiments I proceeded to that with the boil- ing oil, putting at first a very small drop considerably heated on the tongue, and afterwards increasing the dose and the temperature. The effect corresponded precisely to my expec- tation: the oil put on the tongue thus prepared made a hissing noise, similar to that made by red-hot iron when brought in contact with a humid body ; after the hissing the oil ceased to be hot, and was easily swallowed, perhaps ina state scarcely tepid. Thus furnished with facts, I now be- lieved or the pretended Phenomenon of Incombustibility. 53 jieved myself in a state to give the following explanation of the phenomena which I had seen executed by Sefior Lionetto. I. The hair over which he passed the plate of red-hot iron had been first bathed in a solution of alum or in sulphu- ous acid, substances with which it was still wet even at the moment when touched with the iron. Hence the origin of the vapour which arises from his hair in this experiment. II. The plate of red-hot iron with which he rubbed his Jez and arm produced no alteration, because those parts were prepared with the substances of which I have spoken. IIIf. The same reason will explain the phenomenon of the stroke which he gave the red-hot iron with his foot, al- though the contact of the iron in this experiment was longer : but it is not difficult to comprehend how the sole of the foot may be conveniently prepared for this purpose, by the above or similar substances, it being in its nature the most callous and least sensible part of the body.. The contact however of his foot with the plate of red-hot iron was certainly not of very long duration ; on the contrary, it clearly appeared in this experiment, more than in any other, that his incom- bustibility did not surpass a certain limit, beyond which he might be burned, and like others was highly combustible. TV. With regard to the boiling oil; this phenomenon, as being the most striking in appearance, merits a more mi- nute examination. To understand well such a fact, it is necessary to know the following particulars. Seftor Lionetto took the inflamed oil from the fire, and, to give the publica - proof of its high temperature, immersed in it a certain por- tion of lead, which melted, thereby demonstrating to what degree it was heated. To me it appears that such an artifice should contribute to cool the oi]: this is clearly manifested by the known laws of caloric, the greater part of which is employed in the fusion of the lead. I was better convinced of this truth in repeating the same experiment with a ther- mometer in my hand, which after the fusion of the lead fell most sensibly. Of all the oil thus reduced to this tempera- ture, he took barely a quarter of a spoonful ; and this quan- tity he dexterously made to fall on his tongue only, which was perhaps prepared in such a manner that it cooled in an ee D3 instant 54 Memoir on the Incombustible Man; instant the oil, which was then swallowed scarcely tepid.’ The experimenter certainly never drank at one draught alone the dose of oil which he swallowed at several times, nor ever ventured to take in his mouth a whole apoanial of boiling oil. Vie The experiment, with liquid lead, of which, with the extremity of his fingers, he put a very small portion not in his mouth, but on his tongue, requires no other explanation than the be ain. VI. The red-hot iron also which he passed enone over the back of his tongue produced no alteration on it, as he had perhaps clothed it with the plaster of which I have already spoken. | VII. Washing himself with nitric acid, ‘exposing his face to the vapours which arose from sulphuric or nitric acids — thrown on the fire, are experiments equivalent to those with sulphurous and nitrous acid; and also putting his face ex- posed for a time to the flame of blazing oil, are phenomena which do not merit any particular examination, and which certainly present nothing different from the others. The force of habit, the callousness which the skin after a time acquires by the continued exercise of such experiments, and the preceding preparations of the exterior surface of the body, are reasons sufficient to explain easily all the phenomena of this kind. But, How 1s it possible that the transparent and opaque cornea of the eyes and the organs of respiration are not aflected by the powerful action of acid vapours? It would be madness to believe that he held or could hold his eyes open when his face was exposed to the contact of such vapours ; and if he respired at the same time he must t inevi- tably become a victim of such temerity. In the experiment with a piece of iron almost red- hot be- tween his teeth, and, which he held there for a short time, it was sufficient to observe at that moment the visaye of the experimenter, to see the impression of uneasiness and even acute pain delineated. In this experiment without douht, more than in any other, he suffered; and hence the cause why Sefior Lionetto seldom repeated it. His teeth indeed are blackened and spoiled to the last degree. It or the pretended Phenomenon of Incombustibility. 55 It will not now be improper ‘to show practically what method should be adopted by any person wishing to become in this sense incombustible. First of all, it is necessary to be convinced from the beginning, that by frequent frictions and practice on the skin, any one may become as able as Seiior Lionetto is at present to bear the action of fire, and as he was the first time he attempted similar experiments. In the second place it is necessary, that whoever undertakes to practise such operations on his skin, should be informed that he will not attain a certain perfection without at the same time changing his nature, by becoming hardier and consequently less sensible. I would here premise, that-whoever desires to. make simi- Jar experiments, should commence by rubbing themselves with dilute sulphurous acid, or with the saturated solution of alum, agitated or boiled as above. The more numerous the frictions the more insensible the skin will hecome, and also the more proper to sustain the action of fire; and, as I have before observed, the alum made to bail or ferment into a spongy form acquires a greater force, and is therefore preferable to the simple solution of alum. With this usage alone, after rubbing very often the part over which it is de- signed to pass the red-hot iron, it will become capable of bearing its action. But to attain this object by these means a certain space of time is necessary. If any one wishes to become capable of sustaining the action of fire, he must rub very often with one or other of the above liquids, and also with a piece of hard soap slightly moistened, on the same part, in order that it may acquire a slight incrustation. The kind of plaster, of which I have before spoken, formed by ° the trituration of soap in a mortar with a solution of alum, will be the most proper means of rendering the part anoint- ed insensible to the action of fire: a plate of red-hot iron may then be passed over it without occasioning any disagree- able sensation. This mode, although sufficient for the ob- ject desired, is easier discovered by others than that of touch- ing the part rubbed: with soap. With regard to the tongue; in order that it may be capa- ble of bearing the passage of a perfectly red-hot iron, it is D4 sufficient 56 Memoir on the Incombustible Man, &&c. sufficient to bathe it first with the above solution of alum, and afterwards covering it with a thin stratum of sugar in fine powder, and also rubbing it often with a piece of hard soap. Ifthe tongue, after being bathed in the solution of alum, is rubbed with a piece of lump sugar, it will have the same effect as if covered with the powder of the same sugar. If this preparation is performed with care, a piece of red-hot iron may be often drawn successively across the tongue without experiencing the least sensation of heat. The tongue. prepared in this manner will be very able to sustain the ac- tion of a little very hot oil, or a little melted lead, if the operator has the dexterity ta make it fall precisely on the . part prepared. Here then the mystery of the pretended incombustibility is unfolded, and also the means by which any one may at pleasure become incombustible, if the state of preparation which I have desenbed, and with which one can suffer only for a certain time the action of fire, merits the epithet. Hence every one may easily know, that by chemical means only we could not explain with sufficient facility the afore- said phenomena, if it were wished to exclude the insensi- bility which the nerves of the skin in such experiments must necessarily acquire, especially by the known means fit to tepel the force of the caloric after their first application. Were they employed at the time of the experiment, they. would be so easily recognised as to destroy the necessary il- Jusion. In this first edsaiy I did not wish to enter-at greater length into a chemico-physiological examination eer such an interesting phenomenon indeed merits, designing rather to notice facts. In a second essay, however, I can with greater advantage occupy myself with the chemical philosophy, ‘as well as that which belongs to animal life, more diffusely ; and with greater precision treat of this subject, which has deservedly excited universal attention. VII. Ana- Bernal Tosiu) VII. Analysis of the lately discovered Mineral Waters ‘at Chelienham; and also of other Medicinal Springs in tés Neizhlourhood. By Vrrpericx Accum, M.R.TI, 4, Operative Chemist, Lecturer on Practical Chemistry and on Mineralogy and Pharmacy, &c. {Concluded from vol. xxxi. p. 213.] ANALYSIS OF THE CHALYBEATE SPRING CALLED MR. BARREL’S WELL. Tae spring known by this name is situated in a meadow, about three or four hundred yards from the upper extremity of the town of Cheltenham. And although it had long been resorted to by the country people, as an efficacious remedy , against various complaints, it was not otherwise noticed, except by Dr. Fothergill in his Treatise on the Cheltenham Waters, in the year 1788. This spring has lately been opened by the proprietor, a pump-room has been erected, with other conveniencies to render it werthy of the notice which it deserves. The produce of ‘water which this well affords is upwards of 100 gallons in an hour, a much larger quantity than will Det be ever consumed by the drink- ers who visit it. : The first portion of water which the spring yields in the ‘Morning, or after having been left undisturbed for some time, contains a considerable quantity of brown ferruginous filaments. This portien being rejected, the rest of the water which is pumped is as clear as crystal. It produces a kind of greasy feel on glasses which are continually wetted with it, and soon deposits on them a strong coat of brown oxide of iron, Over the surface of this spring, which is enclosed in a small building constructed of brick, and surrounded with a beau- tiful plantation of trees, a dense atmosphere of carbonic acid gas is manifest. The sides of the reservoir of the spring are lined with a thick cream-like substance, wholly composed of carbonate of iron, and a considerable stratum of the same substance is deposited at the bottom of the well. These facts alone are sufficient indications of the intrinsic yalue of this fountain of health, Without stating the indi- vidual 58 . . Analysis of the lately discovered yidual chemical operations which were undertaken to learn the constitution of this spring, we shall merely state its con-- stitution, which is as follows : \ “Contents 12 one Gallon. In one Pint. } Grains. Grains. Carbonate of iron - «4:5 0°5625 Carbonate oflime - 7° 0°875 ee Muriate of soda -. 8°F5 - 109375 ; Muriate of magnesia - 1°25 0°15625 Muriate of lime panini 0°25 Sulphate of lime - 5:5 0:6875 29° 3°625 Cubic inches. Cubic inches. Carbonic acid gas - 12°75 1°59375 Atmospheric air - 5° 0-625 lfm) DONS ia orem f ANALYSIS OF THE CHALYBEATE SPRING NAMED COL. REDDLE’S WELL. This spring greatly resembles the well just described. It is situated in the beautiful spot of Chéltenham, called Cam- bray. Its analysis yielded the following results: Contents in one Gallon. Tn one Pint. Grains. Grains. Carbonate of iron - 3°7 0°4625 Carbonate of lime = 675: 078125 Muriate of soda - 5s 0625 Muriate of lime = 3°5 0°4375 Sulphate of lime = 3: ii 0'375 Q\°7 GIN 25 ; Cubic inches. Cubic inches, Carbonic acid gas - 11°5 1:4375 Atmospheric air - 4° 0°5 1575 1°9375 “ From Mineral Waters at Cheltenham. Les | From what bas been so far stated, it is evident that Na- ture has been particularly bountiful in bestowing mineral springs upon the town of Cheltenham. The valley ot Glou- cester indeed is remarkable for the number of mineral waters with which it abounds, ANALYSIS OF THE MINERAL SPRING AT ALSTON, At Alston villa, in the neighbourhood of Cheltenham, a mineral spring was discovered a few years ago on the estate of Mr. Sealy, in digging for water. This well is remarkable for the large quantity of saline matters which it contained when our analysis was made*, and which surpasses that of any other spring in the vicinity of Cheltenham. Its corpe= nent parts are as tollow: Contents in one Gallon: In one Pint. : Grains. Grains. . “Muriate of soda - 267°5 33°4375 Sulphate of magnesia Sz: -10°875 Sulphate of soda - 104°75 13°009375 -Mariate of lime - 28° 3°5 Carbonate of iron Pilbiie| 0°3875 Sulphate of lime Ami C hy 12°195 AOI TATA 587°35 73°41875 Cubic inches, Cubic inches. Carbonic acid gas - 32 0°4375 Atmospheric air - - 4 O75" ‘ 4 7'5 0°9375 eee ANALYSIS OF THE MINERAL SPRING AT ARLE. At Arle, one mile from Cheltenham, on the south side of a public road, is a spring which rises in a swamp, It * The constitition of this water differs according as the water is suffered to remain a longer time, or not, in the well, and also accordingly as it is taken from near the surface, or from near the bottom of the well. The well is 60 feet deep, and held 45 feet of water ; it is six feet in diameter. was eo | Analysis of the lately discovered was first noticed by Dr. Short, in the year 1740. ‘Its com - position is the following: | Contents in one Gallon. In one Pint, Grains. | Grains. Sulphate of soda = Q° 0°25 Carbonate of lime - 3° 0:375 Carbonate of iron + - 1°25 0'15625 Sulphate of lime - 43333 0°54166 Moriate of soda - = 7:195 ~ 0'89062 17°7083 92°91353 Cubic inches. Cubic inches. Carbonic acid gas - 4°: 0°5 Common air - - 5°5 0°6875 9°5 ; 1°1875 ns EE ANALYSIS OF THE MINERAL SPRING AT WALTON. At the village of Walton, nearly seven miles distant from Cheltenham, and one from Tewkesbury, there is a mineral water first described by Dr. Johnston of Worcester, in the year 1787. It is composed of Contents in one Gallon. Inone Pint. Grains. Grains. Sulphate of soda - Lar re 1°875 . Carbonate of lime - 3° 0°375 Muriate of lime - 4° 0:5 Sulphate of lime mii pals 1°625 Bo: 4'375 Cubic inches. Cubic inches. * Atmospheric air - - 2°5 0°3125 Carbonic acid gas_—- 7°75 0°9687 5. 10°25. «198195 bapa t= 3 : ANALYSIS —_ Mineral Waters at Cheltenham. Gl ANALYSIS OF THE MINERAL SPRING AT NANTON. At Nanton, about nine miles from Cheltenham, and half a inile from Todington, on the Tewkesbury road, is situated a spring which has been long known, and attempts have been made to obtain from it by evaporation its solid saline contents; which attempt proved successful, but the brown tinge which the saline matter is said to have exhibited, ren- dered the sale of it abortive. This water 1s composed of Contents in one Gallon. In one Pint. Grains. Grains. Sulphate of magnesia 87°75 10°96875 Sulphate of soda - 9° 1°195_ Mauriate of lime - 3:95 0:40625 Muriate of magnesia - cat 0°25 Carbonate of iron - 0°5 0°625 Sulphate of lime - 14° 1°75 —-116°50 14°5625 Cubic inches. Cubic iwmenee Carbonic acid gas - 5°75 0°71875 Common air - = A’5 0°5625 i 10:25 1°28195 ANALYSIS OF THE MINERAL SPRING AT PRESBURY. _ This mineral water is known under the name of ihe Hyde Spring. It was first noticed by Dr: Linden, in the year 1750, and recommended by him as equal in efficacy to that of the Cheltenham Spa. It has not acquired much reputa-_ tion as a medicinal water, but large quantities of medicinal salt have been obtained from it in the usual manner, during a-series of years. The water is now only used for the most rude purposes of rural economy. Its composition is as follows : Sulphate 62 | _On the Nature of the Earths. Contents in one Gallon. In one Pint. (i Grains. , Grains, Sulphate of soda - . 92 a Muniate of soda = PPR a nae _ Sulphate of magnesia 14: eg Mee \ Carbonate of iron - 05 0:0625 Sulphate of lime - 9° 1125 132°5 -16°5625 ~ Cubic inches. Cubic inches. Carbonic acid gas - 9°75 191875 |) Common air ° 4: O°5 13273 1°7.1875 VIII. On the Nature of the Earths. : -To Mr. Tilloch. SIR, To place every man’s merits in a conspicuous point of / view, and to hold modest worth up to the admiration it de- serves, is laudable; and if the motive for such conduct be indeed uninfluenced by other considerations, it must chal- lenge universal applause. I am led to this remark by a paper in the last Number of your Magazine, signed O., on the Nature of the Earths. Its author sets out with stating, that “« the result of the late experiments by Messrs. Davy, Ber- zelius, and Pontin, has only contirmed the idea entertained by Lavoisier and others, with regard to the nature of earths, alkalis, &c.”’ That barytes and strontites were Jong since suspected to be of a metallic nature, from their high specific gravities, is well known, ‘and the similarity of the properties of the earths and metallic oxides did not escape the observation of the old chemists. I have not the experiments of Messrs. Toudi and Ruprecht to refer to at this moment, but if my memory does not deceive me, they were very far from effect- ing On the Nature of the Earths. 63 ing the decomposition of either barytes, magnesia, or lime; nor can I agree with your correspondent O., that the ob- jections of ‘Klaproth and Tihawski, to the accuracy of the results of Toudi and Ruprecht’s experiments, do not affect - the purpose for which he has introduced them. These re- sulis, Mr. Q. tells us, were noticed by Mr. Robert Kerr, in the second English edition of Lavoisier’s Elements of Che- mistry, accompanied with some original remarks, which O. copies. I am as much inclined to allow Mr. Kerr all the merit he deserves, as his friend Mr. O. can be, and am ready to acknowledge that his remarks are striking, parti- cularly the fallavanes mentioned in the note, that “¢ from , analogy we may presume potash to be a metallic substance in some hitherto unknown state of combination.” But, sir, this conclusion was drawn from incorrect data, viz. from some experiments published in the Transactions of the Turin Academy, (from which O. says Mr. Kerr’s Opinions re~ ceived corroboration!) which gave reason for supposing soda to be a modification of magnesia. Now we know that soda is not a-modification of magnesia, neither had magnesia, at that time, been proved to be a metallic oxide, for Toudi and Ruprecht’s experiments were far from satis- factory. I cannot therefore allow Mr. Kerr any other merit on this head, than that of having made a very fortunate ate at this philosophical enigma ; for the mere supposition of a fact, and the proof, are very different things. Ages ago the alchemists supposed gold to be a compound body, and all the world knows how earnestly and bow fruitlessly they laboured to prove it so. Fire may be a compound, and thete is just reason to think it is; but what is all this but conjecture ?—a field of all others the easiest to indulge in; and if men are continually guessing , 1t would be indeed extraordinary if they did not sometimes approach the truth. But indeed O., a few lines further, seems to be perfectly of my, opinion, allowing at the time Mr. Kerr nade his conjectures they might have appeared chimerical ; that is, allowing they were neither more nor less than so many guesses. But, I repeat, I am far from wishing to deprive Mr. Kerr of any well-earned praises, (and his Translation of y 64 On the Nature 6f the Barths: of the Elémens de Chimie proves hjs title to a large share,) nor should I have taken this public notice of O.’s paper, but for the very extraordinary, and I must add idfiberal and — unjust epithets, which he has thought fit to apply to the Hig made by “¢ an English professor of high respec- tability? (Mr. Davy) to the conclusions drawn by M. Braconnot ‘from his experiments on the “¢ nutrition of vegetables.” M. Braconnot’s experiments were certainly conducted with great ingenuity and apparent accuracy, and, supposing the facts to be precisely as he imagines, would lead to the extraordinary conclusion, that plants derive no nourishment from any source but water and helt, and gon-- sequently that all manure is uscless, except to enable the soil to retain the necessary quantity of moisture. But al- though it 1s probable that charcoal does contain ylenaae it is ix, no means proved, nor is the fact at all likely, that charcoal is nothing else but hydrogen in a certain modified. form, as M. Braconnot seems to think may be the case: and it 7s proved by Mr. Davy, and mosg satisfactorily so, (vide his Bakerian Lecture, Philosophical Transactions, 1807, part i.) that even distilled water commonly. con- tains both saline and metallic impregnations, which would afford much, probably ample, food to the seeds sown by M. Braconnot in his experiments. The sand also, Mr. Davy observes, may contain carbon and various inflammable mat- ters, which the process of washing in weak muriatic acid could not deprive it of: and it is perfectly true, (though per- -haps O. may not be aware of it,) that a stone containing carbonate of lime, in very-small proportion to the other in-. gredients, is very slightly acted on by acid. Yet these O. calls ** captious and gejune’”’ objections! I cannot but testify my surprise, that expressions so unwarrantable should have found admission into your respectable Magazine; and I am convinced they must have escaped your notice. It is ever the fate of transcendent powers to excite the jealousy of little minds; and 1 am sorry to say, this is not the only in- stance in which the author of the glorious discovery of the: true nature of the alkalis has experienced a shameful want. ef candour from self-constituted judges, whose abilities are inadequate - On the Nature of the Earths. 65 amadequate to the task they have allotted themselves, and whose illiberal spirit would draw a veil over that merit, the lustre of which is painful to the blinking eyes of envy and detraction. I say, Mr. Davy’s discoveries are glorious—for they were not the result of a parcel of guesses; but (as most justly observed by TriBunus, in the Times of the 5th of this month *,) of a fine train of reasoning, from data of his own. And I am ata loss which to admire most, the pene- tration * Trigvnvs, in the article alluded to by Putnarerues Jun., expresses himself thus:—“ The (Edinburgh) reviewers begin with pouring forth their admiration of the late discoveries which. have been made by the agency of Galvanism ; and it might have been expected that joy should have produced séme feelings of complacency, towards the author. Butno;—having men- tioned the name of Newton, they were seized with a superstitious horror, Jest they should have been supposed to compare the living with the dead. In their zeal to expiate this imagiuary offence, they treat the author of the Bakerian Lecture with a levity bordering on insolent contempt : they attri- bute his successes to chance, forgetting that the data on which the late brilliant experiments were founded were supplied by lis own previous discoveries. ‘The name of Newton (and be it ever venerated with piety, but without superstition,) still inspires some secret, mysterious feeling of fear: fear leads to injustice, injustice to inconsistency : thus, though they smile at the Royal Institution in one sentence, they exalt it in another ; and ‘without allowing the author any other merit than his dexterous manipulations, they attrilute to its magnificent apparatus all the honour of his discovery. Finally, with an awkward con- sciousness, they declare, that ‘ they throw out these things from no invidious motive, but merely from a desire to reduce things to their proper level, and just preportions; and to qualify a little of that excessive admiration which has lately been excited by Mr. Davy’s discoveries, not unnaturally, but very ex- travagantly, and, as usually happens in such cases, to the great detriment of sober inquiry.” That they were actuated by no invidious motive, I am will- “ing to believe; candour scorns to attribute an intention to commit injury, where no such power is found to exist. The authority of criticism extends only to those subjects of which opinion is the arbitress : a mere hypothesis is open to its inquisition, but facts are not alterable by human reasoning: the experimental philosopher is equally independent of popular suffrage or lite- rary censure: in his works he shall be essayed by time—he shal! become the fellow-labourer of posterity: his fame is formed of other elements than the smiles or frowns of cotemporaries: he may receive titles of distinction from men, but his real dignity can alone be derived from truth. Having exone- rated the Edinburgh reviewers from all invidious motives, I confess Iam at a loss to find any rational explanation of their conduct : it has probably been dictated by solicitude to prevent the excesstve admiration~ inspired by Mr. Davy from exciting visfonary speculations in science ; it is even possible that it originated in an apprehension that his transcendent success might- damp “Vol, 32. No. 125. Oct. 1808. ei ty the 66 Description of a Machine tration of his genius, or his perseverance and accuracy in ~ prosecuting his researches. ; As you have published O.’s remarks, I trust to your jus- tice to insert these in your Magazine also; and | have the honour to remain, Sir, your obedient servant, - PHILALETHES Jun. Chichester, s October 16, 1808. v Oh IX. Description of a Machine for beating out Hemp-seeds and Flax-seeds ; invented by Mr, Ezexren CLEay, of West Coker, Somersetshire*. ; SIR, I MADE a model of a machine for thrashing out hemp-seed and flax-seed, in the year 18033 and in ihe year 1805 [ had a real machine made after the plan of the model, by Mr. John Wadman, carpenter and hemp-merchant. - The said machine has been since tried and approved ee si hemp- and flax-merchants. I now send the model for the inspection of the Society, and leave the event thereof to their decision. It does not injure the stalk of the hemp so much as the common mode of thrashing out the seed, and consequently leaves it much better for scaling. I am, sir, your humble servant, : EZEKIEL CLEALL. West Coker, near Yeovil, Somerset, March 22, 1806. We whose names are hereunto subscribed, do certify, that we well know Mr. Ezekiel Cleall, of West Coker; that we have many times seen his machine at work, in thrashing out hemp-seed and flax-seed, and think it likely to be of the ardour of other experimentists, and instead of provoking emulation in- duce despondence. I cannet- but lament that any motives of patriotism or prudence, however amiable or respectable, should have led them to insert a passage so Susceptible of misinterpretation, and so obvious to censure.” Epir, * From Transactions of the nia Sor the Encouragement of Arts, Manufac- tures, and Commerce, for 1807.——The sum of 20 guineas was voted by the Society to Mr. Cleall for this communication, anda model is placediin the Societ¥s repository for the inspection of the public, " great ‘ Jor beating out Hemp-seeds and Plax-seeds. 67 great public utility ; inasmuch as two women, whose wages and allowance never exceed one half of what are allowed to two men, will do as much work in any given time as such two men. ‘That the seeds thrashed by this machine are not so much bruised or injured as by the old or common way, and the hemp and flax are preserved from many injuries which they suffer from the old method. In witness whereof, we have hereunto added our signa- tures, Joun WADMAN. James WaDMAN. JoHN BAKER. JOHN PINNEY. West Coker, Feb. 1807. JOHN CHAFFEY. To C. Taytor, M.D. Sec. —— SIR, Tue machine, of which a model was sent to the Society some months ago, must be used with eight flails, two on each arm, for beating out hemp-seed. When required to be used for beating out flax-geed, the above eight flails must be taken out, and four beaters put in their place. The height of the machine from the floor to the top of the board on which the flax or hemp 1s laid, is two feet; the breadth, two feet ten inches; the length of the board, four feet four inches; the length of each of the arms, from the axis of the machine, is three feet two inches; the flails for the hemp-seed, two feet two inches long; the heights of the uprights, seven feet two. inches ; the beaters for the flax- seeds are each one foot three aches long, and seven inches broad. The machine will thrash, in one - day, as much hemp. as grows on an acre of land, and other crops in proportion ; and the work is done with less than half the expense of thrashing in the usual way. ; I am, sir, your obedient sariaiits \ EzekieL CLEALL. West Coker, Aug. 13, 1807. To C, Taytor, M.D. Sec. E2 Reference ‘ 1 68 / Description of a Machine, &¥c. » Reference tothe Engraving of Mr. Cleall’s Machine for beat- ing out Hemp-seeds and Flax-seeds. Plate I. Fig. 1, 2. | Fig. 1. Represents the machine for beating out hemp- seeds, in which A is the table or board on which the hemp is to be placed; B the axis in which the four arms, CCCC, are fixed; DDDD, eight single flails, moving upon four pins near the extremities of the four arms; these flails di- verge from the pins on which they move, so that two of them united on each arm are nearly in the form of the let- ter V. Eis the winch or handle by which the machine is put in motion ; FF, two upright pieces of wood to sustain’ the axle of the machine; G, an upper cross-piece, to secure the uprights fi firm; HH,.the two bottom pieces or sills, in which the two uprights are mortised, also the two smaller | uprights which support the board or table A ; TI, two lower cross-pieces to secure the machine firmly ; KK, two levers on which the table A rests, and by which it may be raised or lowered as theught necessary by iron pins, at K K, pass- ing through these levers and the two uprights. When the machine is used, the hemp must be laid on the table A, and moved about in different directions by the ‘person who holds it, whilst another person turns the ma- chine by the handle E; the flails D of the machine fall in succession on the hemp; as the axis moves round they beat out the seeds as different surfaces of the hemp are exposed on the table; and whén the seeds are all beaten out from one parcel of hemp, a fresh quantity is applicd upen the | table. Fig. 2. Represents one of the flax-beaters, which is made of a solid piece of wood, one of which is attached instead of the two flails, to. every arm, when the machine is em- ployed for beating out flax-seeds, as they require more force to separate them from the flax plant. \ \ xe Be. [6] cee X. ene: of a Machine for breaking Hemp, with O0- servations on the Culture of Hemp in- Cae By Wi11- LIAM Bonn, Esq., of Canada*. | dus culture of hemp in Upper Canada is no doubt one of the most desirable objects with every person of discernment settled there, and more particularly so with those of this description in our mother country; and though there are so many milltons of acres so well calculated to- the growth of this highly valuable article, yet I do not expect much _pro- gress therein for some time, for the following reasons : The part of the country the best calculated for the growth of hemp is so lately and in so small a degree occupied, that few have begun to use the plough, but depend upon raising a sufficiency of grain by harrowing only; in this they are not disappointed for two or three crops ;—in the mean time they clear away fresh fields from the woods, many of them to a large extent, which take up so much time in fencing and dressing, that few of the-farmers have been able to raise more than needful for their own families’ consumption, and for the use of their neighbours; indced they are ignorant as to the growth and management of hemp, and in general so poor, that they cannot afford to raise any thing for sale that will not bring them ready money as soon as brought to market; and grain brings such a high price in cash, that few farmers are inclined to turn their attention to any other article. Another obstacle is, there being no person or per- sons appointed to buy small quent of hemp, and pay ready money for the same. The tract of rich hemp land in Upper Canada is that Dae west of Yonge Streett, and north of Dundas Street f, and partly enclosed by Lakes Ontano, St. Clair, Huron and * From Transactions of the Society for the Encouragement of Arts, Manufac- tures, and Commerce, for 1807. For this communication and the article that immediately follows it, the Society voted their silver medal to Mr. Bond. A model of the machine 1s preserved in the Society’s repository. + A strect leading from York, the seat of EOveUaaienE, to the Bava G waters of Lake Simcoe. { Leading to the River Thames. Bes sy eonmneoes 70 Description of a Machine for breaking Hemp, Simcoe, and to the east and north-east almost as far as. Grand or Ottaway River, and to within a few miles of the south and south-east side of Lake Huron. I have not failed to make annually from one to three journeys through this tract; I have crossed it in all directions with Indian guides, great part of which no white man, except myself, has ever set foot in; and I find, that chief of the interior part con- Sists of a rial deep black soil, which Tam well convinced, when well inhabited with farmers, will become one of the finest countries in al] his majesty’s territories for the eauge of hemp. It is only about five years since this valuable tract began to be occupied at all, and though by industrious farmers, yet by such as have brought little to the country. A few cows and sheep, a pair of plough-oxen, one or two horses, a small stock of farming tools, such as two or three axes, as many hoes and iron wedges, one or two ox-chains, being the most that a new settler (generally speaking) possesses on his arrival ; with these they. make a shift to clear away the woods, and divide and fence the Jand with split timber into fields, and they are greatly encouraged to continue clearing away the forest, in consequence of the high price given for the ashes by the potash makers: this eventually will be vastly in their favour, in future, when hemp becomes the object, as it gives time for the roots and stumps of trees to rot, their stock of horses and oxen to increase, which is essentially necessary before the farmer can expect to he suc- cessful in the growth of hemp. It is in this progressive manner that this fine country will be settled ; the nature of things demands the pursuit ; and the first settlers are ina situation capable of putting the same in practice ; 3. their stock of horses and oxen are sufficiently strong to work the ground a second time over, tear up the stumps and roots, plough and pulverize the soil; and until the ground is: brought to this state, it is not fit for hemp, as hemp, in its nature, depends chiefly upon a tap root ; and when this root is interrupted in its progress downwards, it will throw out horizontal ones, which produce horizontal branches also, and the open spaces round the stumps of the trees admitting sa and on the Culiure of Hemp im Canada. . 71 so much air, permits these branches to grow to such 4 Jength and strength as greatly to injure the bark or hemp of the stem. Such hemp, when it comes to the hackle, breaks off, and drags away at the knobs of the branches, so as to leave it short, and make a very great waste; notwithstand- ing, if there was a sure market for as small a quantity as 50lb. there are few farmers but would try the experiment 5 and if one was more successful than the rest, his neighbour would endeavour to find out the reasons why it was so: thus, step by step, the knowledge in the management of hemp would be greatly extended, the farmer would gene- rally be in possession of fresh seed, and when grain becomes less an object, he would feel no fear in turning his attention to the culture of hemp upon a large scale; and, in order to encourage the farmer, it would prove highly advantageous to take in any quantity, great or small, of sound hemp, assorted perhaps into four or five qualities, according to its length, which will vary for some years to come, for the rea- sons before given. — The high price of labour, owing in some measure to the high price of grain, is such, that hemp, agreeable to the present regulations, is not an object with the farmer; if an addition of about a third of the present price was given, it would be an inducement for the farmers to cultivate their old fields in a more spirited manner, which bounty might be taken off again when grain becomes less an object than it is at present, which will soon he the case in time of peace, and no doubt will affect the price of hemp in proportion in the English market. | In all new countries where labourers are scarce, we find nany contrivances calculated for the purpose of reducing labour, more for the sake of expedition than ease; cueh for instance, as the saw-inill, the hoe-ploughs, scythe and cradle for cutting and gathering grain, the wooden machine (drawn round by one horse) for thrashing grain, the iron- shod shovel, drawn by oxen, and held by two handles, as z plough, for the purpose of levelling the roads, &c. &c. Jor are the Americans, or other settlers &c. in this coun- tr, fond of any work that needs violent exercise of the Ea body, fee, Description of a Machine for breaking Hemp, body, which the breaking of hemp in the old way,certainly - occasions, In consequence of requiring a cross ‘motion of each arm,-which makes the breakers complain of a pain about the short ribs on the side they hold the hemp; and on the opposite side a little under the shoulders, so that breaking of hemp in the old way is a great obstacle to its increased culture. To render labour, therefore, somewhat more easy and expeditious, is au object worthy the first at- tention, and I consider it practicable at a small ,expense, and have sent to the Society a model of a machine for this purpose. I have observed among the clothiers’ and_fullers’ ma- chinery, great power and rapid motion proceeding from what is commonly called a dash. wheel, erected across a stream of rapid water, the flies or float boards of which are fixed in the octangular axis, from fifteen to twenty-five feet in length, and from three anda half in depth, each flie. I have seen many corn-mills in Upper Canada, with no other water-wheels than such as the above described, which save a vast expense in raising dams, &c. There are a number of streams in that part af Canada, which I have endeavoured to describe, (as to the practicabi- lity of the various ways of cultivation,) that are well calcu-. lated for such wheels; and where these streams or rivers are not too wide, the axis of the wheel might be extended across so as to reach the land on each side, where I prepare the breakers tobe fixed to go by a tilt the same as a forge ham- mer, and such a simple piece of machinery would not cost more than 70 or 80 dollars, as little iron. would. be wanted, and timber we have for nothing ; and when in motion would employ four breakers and two servers, from whom I should expect as much good work as fifteen or sixteen persons could possibly do in the old way, and that without much, bodily Jabour. de r Mills fot breaking hemp, on the very same principle as that of a saw-mill, as to motion only an addition of an iroy crank, so as to run with two cranks instead of one, witl something of a larger sweep than that of a saw-mill, woud be of vast utility in a neighbourhood of a large growth af . henp, . / and on the Culture of Hemp in Canada. 72 rd hemp; and would not cost more than a common saw-mill ; as thé brakes of the frame continue in motion the samc as that of asaw-mill, twenty men might be employed, who would do as much as fifty or sixty could do im the old way, and with much more ease and pleasure to themselves ; and this is not the only advantage that would result from such mills ; it would cause something of a social meeting, which the youth would be particularly fond of. At such meetings all the defects respecting the culture and management of ‘hemp would be examined irio, and those who raised the best would become ambitious, and try to excel each other; thus we might reasonably expect (hat Upper Canada would ae exceed all aes countries im the world for the growth of good hemp. Reference to the Engraving of Mr. Bond’s Machine for breaking Beam Plate: Is: Figs sy'4. Fig. 3. a. Represents the axis ofa water-wheel, on tien’ is fixed a trunnion of four lifters ).6 8, each of which lifters Taises in succession a lever c, which, by means of a chain connected with it, pulls down another lever d, -and thereby raises the upper part of the double brake e; as each lifter of the trunnion passes the lever c, it allows the upper part of” the brake to fall upon the hemp on the lower part of the brake ff, and by its weight and teeth intersecting the teeth of the lower brake ff, the woody parts of the hemp plant are separated by repeated strokes from the filaments or fibres of the hemp proper for use, and complete the first operation necessary in the preparation of hemp; g isa table on which the woody parts of the hemp fall, and which table gives security and strength to the frame; AAA are the four legs or supports of the frame. Fig. 4. Shows. a section of the teeth of one half of the double brake above mentioned : it is betwixt the upper and lower rows of these teeth that the breaking of the hemp takes place, by the repeated rise and fall of the upper part of the brake upon it. ‘ Fig. 5. Shows the upper part of the brake, 1 in which 11 show the two rows of teeth, k& the two pins on which it is moved, // the part to which «he chain which raises the upper 74 Observations on the Breeding of Rabbits upper part cf the brake is attached. After the breaking of ihe hemp, it is wholly finished for use by scutching or swingling, an operation which may’ be either perouneds by. the hand or machinery, and is cay, executed by either mode. ; y The machinery for breaking hemp should be removed from the rivers previous to the beginning of the frosts. XJ. Observations on the Breeding of Rabbits and other Animals, in Canada. By Wiviiam Bonn, Esq., of Canada*. THE WARREN RABBIT. EB include the interest of the colonists and the mother country also in one and the same pursuit, is not only laud- able, but most likely to succeed, especially where only a trifle of property of the individuals or of the public 1s wanted to set the bountiful hand of Nature to work in a country where animal subsistence and a suitable climate call for the industrious kusbandman, who may in various ways be useful to himself and his country. In my travels through America, I have often been sur- prised that no attempt has been made to introduce, for the purpose of propagation, that useful little animal, the warren rabbit, of such vast importance to the hat manufactory of England. It is chiefly owing to the fur of this animal that the English hats are so much esteemed abroad. It is a fact well known amongst the hatters, that a hat composed of one half of coney wool, one sixth old coat beaver, one sixth pelt beaver, and one sixth Vigonia wool, will wear far pre- ferable to one made of all beaver, as it will keep its shape better, feel more firm, and wear bright and black much longer« ‘The value of the coney wool, the produce of the united kingdom only, is not less, I will venture to say, than 250,0002. per annum ; but the quantity is much diminished, * From Transactions of the Society for the Encouragement of Arts, Manu- factures, and Commerce, for 1807, owing and other Animals in Canada. Y 75 owing to the banishment and persecution they meet with on every side, and so many small warrens taken in for grain land; in consequence of which “it is ime, that some pro- tection should be afforded, if possible, to that important branch of British manufactory (in which coney wool is used) from suffering any inconvenience in the want of so essential an article, and the accomplishment of this grand object I conceive perfectly easy. General Observations —When [ speak of the warren rabbit, J have to observe, that there are in England, as well as in most parts of Europe, three other kinds, viz. the tame rabbit, of various colours, the fur of which is of little value, except the white; the shock rabbit, which has along shaggy fur of little valine. 3 the bush rabbit, lke those of America, which commonly sits as a hare, and the fur of each 1s of a rotten inferior quality. To return to the warren rabbit.—There are two sorts in respect to colour, that is, the common gray, and the silver gray, but little or no difference in respect to the strength and felting qualities of the fur. The nature of this animal is to burrow deep in Sandy ground, and there live in families, nor will they suffer one from a neighbouring family to come amongst them without a severe contest, in which the in- truders are generally glad to retire with the loss of part of their coats, unless when Buu y an enemy, when they find protection. It is scarcely worth while for me to mention a thing so generally known, viz. that rabbits, particularly those of the warren, are the most prolific of all other four-footed animais in the world; nor do I apprehend any difficulty would attend the exporting this little quadruped with safety to any di- stance, provided it was kept dry, and regularly supplied with clean sweet food, and a due regard to the cleanliness of the boxes or places of confinement. ; Twelve or fifteen pair of these valuable animals ken to Upper Canada, and there enclosed within a small space of ground suitable to their nature, but furnished with a few artificial burrows at the first, by way of a nursery, spread oyer those now useless plains, islands, and peninsulas, so well 76 Observations on the Breeding of Rablits well calculated to their nature, would, I will make bold to say, the eighth year after their introduction, furnish. the British market with a valuable raw material, amounting to a large suin, increasing every year with astonishing oping so as to become, ina few years, one amongst the first of. national objects. Tt may be supposed by some, that the above. project is magnified beyond possibility, or even probability ; but from- the serious attention I have paid to the subject, these many years past, as to all points for and against, leaves no room to accuse. myself of being too sanguine; for, if properly ma- naged a few years at ihe first, I cannot find a single thing likely to interrupt their progress. Some idea of the astonishing increase of the rabbit may be had from the following facts : An old doe rabbit will bring forth young nine times in one year, and from four to ten each time; but to allow for casualties, state the number at five each litter, In nine months - - - > - - 45 The females of the first litter will bring forth five times, — the proportion of which is 23 ee produce 62 Those of the second litter four times produce - +4 50 Ditto of ditto third ditto three ditto'ditto . 37. Ditto of ditto second ditto two ditto ditto - 25 Total in one year from one pair Fite ae The third female race of the old dam, and. the second of. the first litter, seldom breed the first year, bat. are. early breeders in the spring following, when we might expect an increase of the whole in proportion to the first pair, if pro- perly attended-to and protected. Tt is generally allowed, that hares are not more than one - fourth as prolific as rabbits, notwithstanding, agreeable to an experiment tried by Lord Ribblesdale, eo enclosed a pair of bares for one year, the offspring was (as I have been cre- dibly informed) 68: these animals, could they be exported to Upper Canada with safety, and there protected within enclosures. for a few years, would soon after spread over a ) large and other Animals in Canada: 77 large extent of country : the fur is nearly as valuable as that of the rabbit. In that part of Upper Canada withit’ the 45 degrees of north latitude, and the southern and western boundaries, the climate is nearly the same as that of England, a little hotter a few days in summer, and a little colder a few days in win- ter, agreeable to Fahrenheit’s thermometer, which I have paid great attention to for some years, comparing the same with the observations of the English. The increase of most animals appears much greater in proportion in America than_in England, mankind not ex- cepted ; that of sheep is very apparent to those that pay at- tention to their breeding stock, which gives me hopes, that in 2 few years we shall be able to pay for our woollen cloths in wool, Finding the effect of soil and climate so salutary to sheep, &c., it may be reasonably supposed, that rabbits _will answer the most sanguine expectations, as I understand the wocl of the sheep retains all its nature the same as in England, particularly its strength, and felting qualities among the hatters, which assures me that rabbit wool from those bred in Upper Canada will do the same; and there are some millions of acres within the latitude and boundaries” which T have before described, suited to the nature of the warren rabbit ; nor do I apprehend that the wolves, ‘foxes, _&e., of Upper Canada will be half so destructive as the poachers in England. The Cunaees or camel-sheep of South America, no doubt will be a national object at some future period. This is a tame, domestic animal, very hardy, and used with __ much cruelty by the natives in travelling over the mountains with their burthens; it shears a fleece of wool of from @lb. to 3lb., which is of dusky red on the back ; on the sides inclined to white, and under the belly quite white; its tex- ture is very fine, yet strong; its felting qualities very powerful, and is worth, when ready for use, from five to fifteen shillings per pouud. This animal would ‘no doubt thrive, and do well in England, Upper Canada, eel in ‘par- ticular I should-suppose in New Ffolland. The Beaver might be propagated ta great advantage in ; Seotland, ~ 78 On the Desulphuration of Metals. Scotland, Ireland, and northern parts of England. It is an animal, when tamed, very familiar, and will eat bread and milk, willow-sticks, elm, bark, &c., and no doubt might be imported with safety ; but as these two last-men- tioned animals are not likely to be attended to immediately, I shall say no more respecting them for the present. Pine Timber. There are many thousand of large pine trees on the borders of the lakes, rivers, &c. in Upper Ca- nada, which might be marked and secured for naval pur- poses, and which might be floated down to Montreal and Quebec with great ease, and which no doubt would be of great benefit in furnishing a large supply of good masts for the navy of this empire. XII. Memoir upon the Desulphuration of Metals. . By M. Gueniveau, Engineer to the Mines. [Concluded from vol. xxxi. p. 213.] Roasting of Galena. Ix is extremely difficult completely to desulphurate galena by roasting: the affinity of its component parts for oxy- gen does indeed effect their disunion quickly enough; but that of the new compounds, the sulphuric acid and the oxide of lead, gives birth to a new combination, which re- tains the sulphur, and thus. forms an obstacle to the desul- phuration: to this same affinity of the oxide of lead for the sulphuric acid, we must attribute the facility with which this acid is formed in the roasting of galena. I shall examine in detail the various processes to which this important decomposition gives rise, as I think they will explain numerous and complex phenomena. Whatever care is taken in roasting galena, it is impossible to convert all the sulphur into suiphurous acid, and to avoid the formation of sulphuric acid; the result always ‘gives a mixture of oxide and of sulphate of lead. In roastings performed upon a large seale, and in a regu- lated atmosphere, the proportion of sulphate of lead is much more ‘ On the Desulphuration of Metals. 79 more considerable, it is regulated by the temperature and by the facility with which the air penetrates the ore; nu- merous experiments made in /’ Ecole des Mines incline me to think that the roasted schlich of the Pezey ore contains half its weight of sulphate of lead; whence it follows, that even supposing the whole galena to be decomposed, the. roasting has not separated the half of the sulphur it con- tains. The reverberating furnace may be employed with great success in roasting the sulphurized ‘ores of lead. In some foundries, they produce in this kind of furnace so complete a separation of the sulphur, that it is sufficient, when the " roasting is supposed to be finished, to add some charcoal, in order to obtain instantaneously a great quantity of metallic lead. I, cannot be doubted, however, that a great quantity of sulphate of lead is formed; which, as we have already seen, is a necessary result of the action of the air upon ga- lena exposed to a high temperatures; the chimneys of the furnaces are likewise’ filled with the above substance: the decomposition of this sulphate by charcoal produces a sul- phuret or a matte of lead; and although sulphurous acid may be disengaged, it is very difficult to explain why the addition of charcoal makes the lead flow instantly in a con- siderable quantity. I thought that the sulphate of lead was decomposed during the roasting, and that nothing remain- ed after this operation, but.an oxide a little mixed; and I thought I discovered the cause of this decomposition in the action of the galena, as yet undecomposed, upon the sulphate formed. The following experiments will show the nature - and result of this action. I put into a retort'a mixture composed of one, part of pulverized sulphuret of lead, and three of sulphate*, and I heated it at first but slowly. When the retort was red-hot, a considerable disengagement of sulphurous acid gas took place which lasted an hour; when the retort melted; the residue presented a mixture of oxide and of sulphate of lead. I ascertained that the sulphurous acid which had been collect- ed in the water was not mixed with sulphuric acid, * This mixture was made in the humid way. This &0 On ihe Desulphuration of Metals. ; This experiment demonstrates in an indisputable man- her the decomposition of the sulphate of lead by the sul- phuret, or rather that of the sulphuri¢ acid which it contains, by the sulphur and the lead of the galena. The sulphurous acid certainly proceeds both from the oxygenation of the sul- pbur, and from the demi-decomposition of the acid, as 1 am convinced that no sulphate remained in the residue. I re- peated this decomposition, employing equal parts of galena and of sulphate ; the sulphurous acid disengaged was more abundant, and there remained in the retort a mixture of oxide and of sulphuret; from which I concluded, thatif, in the first experiinent,- the proportion of sulphuret of lead was too weak, it was too strong in the latter. I also made another attempt to attain some proportions rigorously suf- ficient for the mutual] decomposition, and endeavoured at the same time to assure myself of the oxidation of the lead con- tained in the galena in a metallic state. I put fourteen gram- mes of sulphate, well mixed with eight grammes of sul- “phuret, inva crucible, which I allowed to become red-hot in a gradual manner. L remarked that a considerable. crackling was produced, occasioned by the disengagement of the sulphurous acid. I did not take the crucible from tie fire until I saw its contents melted. I found two substances well scparated ; the one occupying the bottom of the crucible was merely melted sulphuret of lead, without any mixture of ductile lead ; the other presented all the characters of ‘the oxide of lead called glass of lead; this part was a combina- tion of oxide and of silea; presen from the materials of the crucible, without any marks of sulphate of lead. This experiment proved that the lead of the galena was oxidated at the expense of the sulphuric acid; but it did not show the quaatity of galena necessary to the complete decomposition of the sulphate. 1 am of opinion, how- ever, that the proportion of one-part of the former to two of the latter is sufficient ; besides, it ‘closely. resembles the proportion which calculation gives us of the composition of these substances. : The following are the natural consequences of these facts: | ist. The galena_ and the sulphate of lead are mutually de- composed On. the Desulphuration of Metals. 81 composed at a high temperature. 2d. This decomposition gives place to the formation and to the disengagement of a great quantity of sulphurous acid, and consequently to the separation of a considerable portion of the:sulphur contain- ed in the ore*. 3d. The result is oxide of lead, when the proportions are proper; and in the contrary case a mixture of oxide and of sulphat, or oxide and galena. The application of these consequences to the roasting of the sulphuret of lead in this reverberating furnace is very easy. [shall explain the theory of this operation in the way I conceive it. The pulverized galena, or the schdich of lead, spread out upon the floor of the furnace in a layer of a few inches in thickness, the upper part of which is exposed to the action, produces the phenomena usually observed in the common roastings. The heat vaporises a little sulphur; the air converts that part upon which it acts into sulphurous acid, which is liberated; but a much greater part is converted into sulphuric acid, which 1s combined with the lead oxidized at the same time. The ores are stirred ; the sulphate of lead is mixed with the undecomposed schlich, and their decomposition pro- duces sulphurous acid; the surface of the layer which has been renewed, reproduces sulphate, which afterwards serves to produce a new disengagement of gas, and thus continues the desulphuration, to which we find there is no end except the complete decomposition of the galena. If the operation has been well managed, and if too much sulphate of Jead has not been formed, the result of the roasting will be al- most pure oxide of lead; in the contrary case, some sul- phate will probably remain, which charcoal will bring ‘ back to the state of sulphuret, and the decomposition of which willtake place like that of the galena. We may judge from this detail, how important it is to avoid melting the sulphuret of lead subjected to roasting; for the action of the air upon the melted ore will soon be rendered null by * If we admit that a mixture of one part of sulphuret and two of sul- phate are entirely decomposed and reduced to oxide of lead, the quane _ tity of sulphur separated will be two-fifths: so that one part of sulphate, in an indefinite quantity of galena, will separate one-fifth of sulphur; and one \ of sulphuret in sulphate will separate three-fifths. Vol. 32. No. 125. Oct. 1808. FP ite 82 On the Desulphuration of Metals. the formation of the oxide of lead which will cover its and the sulphate of lead not being capable of being any jovisee mixed with the galena, there will be no ide Hig left of ate sulphuration. : The roasting of galena in the reverberating furnace is therefore reduced to the conversion of the sulphur which it contains into sulphurous acid; and as it is produced in a great measure by the intermedium of the sulphate of lead which is continually formed, this process admits of a much more complete desulphuration than the others. The same decomposition of the sulphuret of lead by the sulphate, in my opinion, takes place also in the treatment of the ores of lead in what are called Scotch furnaces: in Scotland they roast and melt galena by one uninterrupted operation, employing coal and turf. This kind of farnace is employed with success in the mine at Pezey, in melting roasted galena containing at least 1 of its weight of sulphate of lead. It gives no mattes as a final result, which proves that it admits of the decompo- sition of the sulphate and the separation of the ‘sulphur contained init. I am of opinion that the action of the portion reduced to the state of su/phuret by the contact of the coals upon the undecomposed sulphate, is one of the principal causes of the desulphuration produced. — We have had occasion to speak of several kinds of fur- naces, (the Fahlun and Scotch furnaces among the rest,) in | which the metallic sulphurets will undergo a real roasting 5 but there are others where this effect is scarcely perceptible. I consider the present as a proper opportunity for intro- ducing some reflections upon the differences they exhibit in this respect. They ought to excite the more interest, be- cause they are intimately connected with the present sub- ject, and explain some phznomena which cannot be ac- counted for from the way in which the operation of roasting has generally been regarded. It is a well- eal fact, in foundries, that the highest, furnaces are those which admit of desulphuration the least, or, in the language of the workmen, they produce the most sufficient pie matles. ok a convincing proof of this is se it will be’. z Tea On the Desulphuration of Metals. 83 sufficient to mention, that at Pezey there have been seen roasted ores of lead, containing a great deal of sulphate of lead, the flux of which, in the Scotch, furnace, gave no mattes, and yet they produce a great quantity when they are passed to the common furnace. If heat alone decomposes easily and completely the me- tallic sulphurets, the upper part of the high furnaces. will be very proper for operating the roasting of ores; for besides the temperature being a little elevated, the air which ascends to that height, being deprived of a part of its oxygen, forms very little more of these sulphates which are opposed to the separation of the sulphur: but it. 1s quite different, and in my eyes it is a new proof of the little effect of the action of caloric alone upon substances. The sulphur is separated” from the sulphurets, as we have seen, in the state of sul- phurous acid, and oxygen is indispensable to its formation. In furnaces not much raised, the air which touches the ore recently thrown in, still contains a great deal of oxygen ; the sulphurous acid formed is soon subjected to the deox-— idating action of the coals; if there be a small portion of it decomposed, a new sulphuret ts formed, which is afterwards roasted like the mineral. In the Scotch furnace, for example, when mattes are melted, they are- thrown successively into the furnace, and what has escaped one operation is decom-~ posed by a second. fn high furnaces, on the contrary, the ores placed in the upper part undergo but a very imperfect desulphuration, because the air which comes in contact with it contains but very little free oxygen, the sulphurous acid formed in the interior is ina great measure decomposed by traversing the whole height of the furnace filled with coals, and the sulphuret is recomposed; the latter tends by its gravity to gain the basin, where it does not arrive until after a series of degompositions, which cannot take place, as we have in fact observed, without there alan @ con-, stderable loss in metal. ; All these facts seem to leave no doubt as to the following proposition : The decomposition of the metallic sulphurets by roasting is produced by the oxygenation of its compounds, Fe _ and Sk On the Desulphuration of Metals. 5 / Jansen and the sulphur is separated more or less completely in the state of sulphurous acid. B) § LEI. Desulphuration of the Metals independent of the Action, of the Air. The varied affinities of sulphur for different mineral sub- stances, furnish the means of decomposing certain sul- phurets; and several have been employed in metallurgy with success. In order that the decomposition of a metallic sulphuret by any mineral should form the basis of a metal- lurgic process, it 1s not sufficient that the affinity of this mineral for sulphur should be greater than that of the metal; it must, besides the conditions required by ceconomy, also. possess several other requisites absolutely necessary for the success of the operation, which considerably limit the num-~ ber of the agents pointed out by chemistry: for instance, if the sulphuret resulting from the decomposition 1s not fusible, or but very little so, if it has the property of combining > with the metal required to be separated, or rather with the still undecomposed sulphuret, it is evident that we cannot effect our purpose, namely, the isolation of the metallic substance. Hitherto little else has been used except lime and 7ron. Desulphuration of Mercury.—It is very easy to decom- pose the sulphuret of mercury; it being sufficient if we present to the sulphur a substance capable of retaining it, and volatilize the mercury alone. It is thus that iron and lime are employed together or separately 1 in the treatment of the ores of cinnabar. c Desulphuration of Copper.—Pyritous copper is melted in | some foundries with lime, either in the common or in the reverberating. furnace; but the process is not well enough known as yet to enable us to judge of the efficacy of lime as an agent in this case. I was once of opinion, with some , catalase that ihe, well-known supertor afinity of iron for sulphur over that of copper for the same combustible, might determine the decomposition of the swlphuret of copper by this metal, at least in| _ On the Desulphuration of Metals. he im certain cases. The following experiments, however, did not warrant me in continuing of this opinion. First Experiment,—I made a mixture of ten grammes of pytitous copper, the composition of which | knew, with four grammes of iron filings: I put this into a crucible, covered with charcoal in powder, and heated it in the forge for, three quarters of an hour. The proportion of the iron had been. calculated so accurately that it was sufficient for taking up all the sulphur combined with the copper in the mineral em- ployed. I found in the crucible a perfectly homogeneous mass, weighing thirteen grammes, which did not contain the smailest globule of metallic copper, nor any appearance of separation, between the sulphuret of iron and that of copper *. Second Experiment.—Another trial was made by employ- ing ten grammes of pyritous copper and five grammes of the same raasted mineral. This is nearly the case with the fluxes in which the ore or the mattes are not completely desulphu- rated; the proportion of the iron was. still sufficient for separating copper, which was very abundant in the mixture. I kept up the heat for three quarters of an hour, and found, as in the preceding experiment, a homogeneous mass, with - out any trace of metallic copper, nor of pure sulphuret. of copper ; this was a real matte of copper. Third Experiment.—On this occasion an equal mixture of crude pyritous copper, and roasted copper, dipped in olive oil, and heated strongly for half an hour in ecrucible, presented nothing but a powder, which had not undergone fusion, on account, without doubt, of the superabundance of the iron. I think these few experiments are sufficient for proving that the desulphuration of copper by means of iron will be always very difficult, because there is formed a triple com- bination between the sulphur, won and copper, or rather.a combination between the sulphurets of copper and of iron, which prevents the separation of the copper. * In the decomposition of galena by iron, we observe, when the latter is in too small quantity, three distinct substances of lead, sulphuret of lead, and lastly, sulphuret of iron in the upper ‘part. ; F3 Desulphuration 85 Report of the City and Finsiury Dispensaries. Desulphuration of Galenu.—This is one of the sulphurets which best yields to the decomposition in question : the fu- sibility of the lead which facilitates its aggregation, as well as the little affinity it has for sulphur, are the causes of the successful trials that have been made on this subject. Lime and 7ron are employed in various circumstances in the de- sulphuration of galena; the use of lime is noi very general, and it is impossible to judge of its effects from what is known of the properties of the sulphuret of lime. ©The treatment of galena by iron is more in use, and appears more advan- tageous, The above memoir will, T hope, suggest several experi- ments to those who are engaged in metallurgical pursuits. All the experiments I have detailed were performed the laboratory belonging to the Council of the Mines, and under the eyes of M. Descostils, by whose superior judge- ment I profited considerably during the. progress of my Jabours, XIII. Report of Surgical Cases in the City and Finsbury Dispensaries, for April, May, and June, 1808. With two Cases of. Dropsy of the Ovarium, By Joun Taunton, Esq. Is April, May, and June, there were admitted on the books of the City and Finsbury Dispensaries 785 surgical pauents. Cured or relieved — 722 Died — -- 6 ; Irregular — pe 2 Under cure. — a3 785 Mrs. Dennison, etat. 29, has generally enjoyed a good state of health till within about eighteen months, when she had symptoms of dropsy of the ovarium; the right side of the abdomen enlarged most, was irregular, and bas been most painful during the continuance of the diSease. The catamenia stopped about a year since, when the abdo- ~ ; . j ‘ men Report of the City and Finsbury Dispensaries. 87 men enlarged more rapidly, and the health became very bad: she was received into an hospital at the beginning of the present year, and continued till May. in such a co. state that it was not thought advisable to operate. Her health being improved, the ‘operation of paracentesis was performed, te sells about five or six quarts of a very thick fluid were evacuated, and that with great pain, from the viclent pressure made use of to force it through the canula. its passage was natur rally s slow, an the operation was tedious in the extreme. . The inconvenience she now (Oct. 21, 1808,) experienced from the great enlargement of the abdomen, induced her again to solicit aid from an operation, hoping to experience more benefit than before. : The abdomen was greatly enlarged in every part, but more so onthe night side, which was unequal, and more painful. The fluctuation could not be distinctly felt by myself, but Dr. Lidderdale thought it was evident. -The large-sized trocar was introduced about three inches below the umbilicus in the linea alba; but the contained maiter was so thick as to prevent its passing along the canula, and only about an ounce of a glary substance, as thick as gelly, but of a fibrous texture, escaped ; some part of which re= sembled that kind of caseous matter frequently foundin scrophulous abscesses. At the upper part of the abdomen near the scrobiculus cordis, the undulating motion of a fluid was evident, but she could not be prevailed upon to be tapped in that part. May 1805.—Mrs. , mtat. 42. About twelve months before this time she thought herself pregnant ; but as the enlargement of the ere was attended with more pain than 1s usual in pregnancy, she applied for advice, and was placed under the care of Dr. Pincard, in the Bloomsbury Dispensary, and was tapped by Mr. Blair; when ouly a small quantity of a gelly-like substance passed the canula, and she died in four days after the operation. On opening the abdomen, the right ovarium reached from the pelvis to the scrobiculus cordis, occupying the whole an- terior part of the abdomen, the viscera of which were ob- F4 seured ¢ 88 _ Notices respecting New Books. y __ scured by this tumour, which contained about three gallons of agelly-like substance, enclosed and supported by innu- -tmerable membranous bands continued across the ovarium in evcry possible direction, so that it could not be pressed out but with oreat force: the uterus was enlarged, and the viscera were covered with lymph. A preparation of the above case is in my museum. JOHN TAUNTON, Greville street, Hatton Garden, Surgeon to the City and Finsbury Dispen= Oct. 24, 1808. saries, and City Truss Society, Lecturer on Anatomy, Surgery, Physiology, &e. XIV... Notices respecting New Books. Msg. CarMICHAEL, of Dublin, has in the press a new edition of his ‘* Essay on the Effects of Carbonate and other Preparations of [ron upon Cancer; with an Inquiry into the Nature of that Disease.”” The work will appear in January next, and has been so much enlarged and improved that: it mav be almost considered an entire new work.—Among the additions are a great number of highly interesting cases: A disquisition on the uses of the oxide of iron in the blood, and remarks on such diseases as depend on its excess or de- ficiency, or in any way bear a relation to cancer; with an attempt to answer the queries of the Medical Society esta- blished in London. for investigating the nature and cure of that complaint. ‘ Mr. Taunton, of Greville-Street, Hatton-Garden, is making arrangements for publishing a small work on Patho- logy, which will be illustrated with copper-plates. 8 a XV. Intelligence and Miscellaneous Articles. DECOMPOSITION OF THE ALKALIS. Ox this interesting subject, in addition to what we have given-in this and our preceding Numbers, we have now t6 state that the French chemists have not only repeated Mr. Davy’s co’ . ' On the Decomposition of the Alkaiis. 89 Davy’s experiments on potash and soda, but confirmed, if any confirmation had been necessary, the accuracy of his researches, by obtaining similar results by a different pro- cess. | MM, Gay and Thenard have succeeded in deoxidating potash by means of iron. The event is announced in Correspondance sur l’ Ecole Imperiale Polytechnique, No.10*, in the following terms: «© A letter from London, dated 23d Nov. 1807, announced that Mr. Davy had ‘succeeded, by means of a strong galvanic pile, in decomposing the two alkalis of potash and soda ; and that Mr. Davy had read, to the Royal Society of Lon- don, a memoir, in which he Samalddedl that these two allealis were metallic oxides. ; “On the sith of December, 1807, Messrs.’ Gay and Thenard repeated at the laboratory of the Polytechnic Schoo} the experiments of Mr. Davy, and actually obtained at the negative pole of a pile, with large plates, the two new metals, - the existence of which had not been even suspected previ- ‘ously to Mr. Davy’s experiments. \ ** The above two chemists, however, continued the in- quiry in a new point of view 5 they proposed to themselves: the discovery of a substance sufficiently oxidizable to take off the oxygen from the alkalis, which had been ascertained to be metallic oxides, and their experiments were ee with the greatest success. “© On the 7th of March, 1808, Messrs. Gay and Thenard informed the Institute of France, that upon treating potash with iron, in the fire of a reverberating furnace, the iron deoxidated the potash and made it pass to the metallic state.” << On the Apparatus best adapted for deoxidating Potash by Iron. By M.Hacuerve. *‘ The gentlemen pages to the Emperor being desirous * Weare indebted to Mr. Davy for the use of this journal. We need scarcely state to our readers that, in the present interrupted state of commun’«. cation between this country and the Continent, we find it extremely difficult to procure the foreign journals. May we add, that our friends who happen to obtain any of them cannot confer on us a greater favour than by allowing us the use of them for a few days? of 30 On ihe Decomposition of the Alkalis, ef secing the new metal obtained from potash, I repeated, at their chemical laboratory, the experiment of Messrs. Gay and Thenard, in presence of the governor to the pages, M. d’Assigny. / ‘© The apparatus is equally simple with that for the de- composition of water by means of iron, and every thing proceeds in the same way as in this last experiment. We "put into a gun-barrel a quantity of iron filings sufficient to fil that part of it which was inserted in the furnace: caustic potash was introduced into one of its ends not in- serted in the furnace, and the extremity was luted ; a tube of safety was adapted to the other extremity.of the gun- barrel, and a strong heat was then applied, “ The furnace I.used upon the occasion was 25 centime- tres in thameter, with double blast bellows. While the fur- nace was strongly heated, I’cooled with ice that part of the gun-barrel which contained the potash: after continuing a strong heat for an hour, I melted the potash by means of a small portable furnace of sheet iron; the gun-barrel being - a little inclined towards the tube of safety, the fused potash came in contact with the iron; in an instant the hydrogen of its water of crystallization was disengaged by the ex- tremity of the tube of safety, which was inserted under. watcr. . “<¢ This disengagement of hydrogen is a certain mark of the success of the experiment. When it slackens, from the liquid potash having cooled the iron, we may remove ‘the _small furnace placed under the potash, which keeps it liquid, and restore to the iron the temperature necessary for re- ceiving new liquid potash. «‘ This last effect is, as we see, completely similar to what takes place in the decomposition of water; for if we pour too much water on the red-hot iron, the metal is cooled, and the water passes off in vapour. without being decomposed. ‘© Before fusing the potash in order to bring it aver the ivon, I placed in ice that part of the gun-barrel to. which ~ the tube of safety is adapted, and which serves as a refri- gerant. “Tr On the Decomposition of the, Alkali. 81 << Tn about half an hour from the moment at which the potash is fused, the disengagement of hydrogen ceases, and the operation is concluded. «¢ When the furnace is quite cold, the safety tube is taken away, and the extremity of the gun-barrel is closed by a plug. In order to extract the metal, the gun-barrel is cut at the commencement of the part which has served fora refrigerant, and the metal (potassium) presents itself im the form cf smail brilliant laminze, adhering to the sides of the gun barrel: the greatest quantity is found close to the re- frigerant ; another portion is not condensed until it is very close to the plug of the safety tube: this last portion ad- heres very-slightly to‘the gun-barrel, and the least effort is sufficient to detach it: itis even partly oxidized by air ad- mitted during the cooling of the furnace; and when the whole is received over naphtha, the oxidized part is de- tached in lamine, and exposes to view a white and brilliant metallic surface. | ¢ <* As to the portion of potash condensed nearer the far- nace, it must be detached by means of a sharp chisel, and in the largest pieces we can possibly break off ; for if it be in small molecules it inflames in the air, even at a verv low temperature. When it cannot be detached in large pieces, it must be kept im a gas deprived of oxygen, or in naphtha: it was by plunging it in oil that I extracted it from the gun- barrel. «*Wealso find in the gun-barrel portions of amaleamated iron and potassium; they adhere very strongly to the part of the gun-barrel which occupies the middle of the furnace ; they become green in the air, and are easily decomposed = the potash returns in a very short time to its first state. <¢ In order to obtain the potassium conveniently, and ona . Jarge scale, we must procure a gun-barrel of a jarge diameter, which must be heated throughout a great part of its length, and with a tube at its extremity, in which liquid potash is kept. This tube must be disposed in such a manner that we may be able to Jet fall whatever quantity.of exide of liquid potasly “we please; and we should yolatilize it before putting itin é | contact 92 On supplying Cities with Water. ary contact with the iron; we should place another gun-barrel, in two,pleces, at the extremity of the former; the barrel composed of two pieces would serve as a refrigerant, and could be opened 1 in order to collect the metal.” Mr. Davy informs us that he has found the above process to answer perfectly. The great precaution necessary is, that the potash should be as dry as possible. The metal obtained is rather heavier than that procured by electricity, and seems to contain a Jittle iron; but is proper for all analytical pur- poses ; ; so that this happy experiment of the French che- — mists puts it in our power to is potassium in consi+ derable quantities. SUPPLYING CITIES WITH WATER. An abundant supply of good water is one of the most in- dispensable requisites for the cleanliness and health of the inhabitants of large towns. Till jately, collections of spring water have been preferred for the purpose of supplying towns by means of pipes; from its supposed greater purity. But ex- perience and the progress of science have proved that spring water is far inferior to river wate fo this purpose. River water contains impurities visible to the eyes—spring water contains them in a state of actual solution, and therefore invisible. From the former the impurities: will separate , themselves almost entirely, by rest or by filtration; from the latter they cannot be separated by means adapted to the demands of common life. Londoa, which is extremely healthy for its size, has long been supplied with river water, and to this, more than to any other circumstance, are the inhabitants indebted for the health they enjoy, though few of them ever take the trouble to filter the water they use, even for culinary purposes. The city of Glasgow, which, till lately, had no supply of water but from wells*, has at length the prospect of an inex- * Dr. Ure, of Glasgow, has, we understand, been lately occupied in ana- lysing the wells and mineral waters in the neighbourhood of that city. The former have been found to contain a surprising quantity of heterogeneous matters in solution. We hope the Doctor will publish his analyses. Kuariphe: On supplying Cities with Water. 93 naustible supply from the river Clyde by means of pipea and steam engines. Two companies have embarked in similar undertakings. One of them, under the direction of Mr. - Thomas Telford, civil engineer, undertakes to bring in a large supply from the eastward of the town} the other, un- der the direction of Mr. Robertson Bech Anan, civil engi- neer, to bring in a similar supply from the westward. Both works are in considerable forwardness, and many houses are already supplied with pipes: but the circumstance | which demands most attention from the public, and which is our principal reason for mentioning these undertakings, is the filtration of the whole supply of water, by means of reservoirs constructed for the purpose. This salutary process is effected by. making the water filter through sand and gravel from the large reservoir into which it is first elevated by the steam engine, into a second reservoir posited a little lower, and from which the conveying-pipes receive their supply. This is the first instance we believe that has yet occurred of water being filtered on so large a scale ; and when its ad- vantages, not only to the health of the inhabitants, but to bleachers, dyers, and other manufacturers, are duly consi- dered, we cannot doubt that it will be adopted in all future -undertakings for supplying towns with water. Hitherto all branches of manufacture connected with the use of water have been obliged to be carried to the water, and the neces- sary hands along with them, and much expense for carriage and extra Jabour has been added to the price. But, should this system become general, manufactures will be carried on where the necessary supply of labourers can be most easily procured, and the goods find the most ready market. We believe that the filtration of water intended for public supply was first practised by a private individual at Paisley. This public-spirited adventurer was amply remunerated for his expenditure ; and we cannot doubt that similar speculas tions on a larger scale, if properly conducted, will yield an ample return to the first subscribers.— We hope the example which has thus been giyen will be followed by public-s: irited individuals in ether large towns. Its benefits would soon be 94 " Astronomis.— Comet. » Ai | be felt, and it would yield advantages to the community, if general which cannot be calculated. - ; ASTRONOMY. Blackheath, Oct. 14. Str,— When I computed the ephemeris of Vesta, whiclt T sent to you last month, J had not at that time reduced any of my late observations; and I calculated the place of the planet, from the elements obtained, near the former opposition, On reducing those of the present year, I found » a considerable change in ‘tthe place of the node, which affect- ed the latitude, and of course the declination. The quantity of this change I cannot at present ascertain ; but having again conrputed the ephemeris, which agrees with the late observations; and also laid down in the chart, all the stars to the seventh magnitude which are near the path of the — planet, (very few of which are contained in any catalogue,) the place of the object may be very readily found, by those who have instruments on an equatorial stand. I remain your obedient servant, To Mr. Tilloch. S. GROOMBERIDGE, Ephemeris of Vesta ai Midnight. | assam Dec. South, Passage over SGA RET bie the Meridian. Oe of kt Oct. St 345°] 16:22 8°36 Noy. 3 345°15 16°5 8°25 od 6 345°34 15°45 S*§.5¢ loa hae 9 345°57 15°23 8°4 12 $46°99))) *. 1 5a 7°33 15 346°51 14°36 8 )— 7°43 18. 347°94 14°11 7°33 2 348'0 13°44 7°23 24 348°39 13°17 7°13 27 349°20 12°49 1:3 30 350°5 12°19 6:53 ‘ CometT.—A comet has for some time been visible to the naked eye. It is at present in the girdle of the constellation | Andromeda, which is distinguished by three stars forming , - acurve; the brightest is of the second magnitude, called’ Mirach, the BENE two of ihe third magnitudes if an ima- Mas ginary > i core List of Patents for New Inventions —Mceteorology. 9% zinary line be drawn from Mirach through the middle star, and continued as much further on the other ‘side, it will pass over the comet. It appears like a star invested with a little light cloud; about half-past seven, it is 45 degrees above the one ee over the east point of the compass, and . passée the meridian néarly in zenith at half-past ten at night. LIST OF PATENTS FOR NEW INVENTIONS. To John Warren, of the town and county of the town of Poole, stonemason, for an apparatus to prevent chimneys from smoking, and to extinguish fires in grates and stoves, without making any dust or smoke myjurions to the room or furniture. Sept. 15th, 1808. To Edward Massey, of Tey redies in-the county of Staf- ford, clock- and watch-maker, for an improved cock for drawing off liquors. Sept. 24th. To Thomas Paton, of the parish of Christ Church, in the county of Surry, engineer, for an improved wheel for various useful purposes. Sept. 24th. To Sebastian Erard, of Great Marlborough-street, in the county of Middlesex, for improvements upon piano fortes, Jarge and small, and upon harps; for which harps he has already obtained Jetters patent. Sept. 24. METEOROLOGY. A number of the provincial newspapers have of late had paragraphs respecting meteors. On comparing the accounts, they seem all to refer to the same meteor, seca at places very remote from each other, and, in all, at nearly the same instant of time, viz. a few minutes palate eight o’clock P. M. Monday the 17th of October. It passed in a north-easterly direction, and apparently at no great altitude ; but its real altitude must have been immense,, or it would not have been scen in so many remote places at the same instant—It was seen as far north as Aberdeen, and as far south as Hull. Its apparent diameter was somewhat less than the moon, and in some places it seemed to have a tail throwing off coruscations of great brilliancy. It diffused a most vivid palé light, and was visible in its progress for a few seconds. METEORO- 96 Thermometer. Days of the Month. Oct. i?) oOOrsktrOwmh ow —- Oo O-} &> 6 AD 10 26 8 o’ Clock, Morning. | Meieorology.’ METEOROLOGICAL TABLE, - By Mr. Carey, OF THE STRAND, For October 1808. Noon. 5aP. 51 46 50 51 50 56 57 63 62 37. 56 54 56 52 53 AS 54 46 47 rag | Height of @) sa) ebe Barom. ct | Inches. 44°| 99°88 492 °55 40 “41 4] ‘55 49 °88 47 "65 47 | 30°04 52 "19 48 1g 47 *02 46 | 29°98 47 Foo 49 78 46 “77 47 "82 40 ‘93 43 | 30°10 40 | 29°40 46 ‘20 43 °56 38 = ehh 41 795 46 *50 4] 72 40 aa 39 °70 30 ‘78 40 “40 50 *64 43 “34 7 cares ness by Leslie’s Hygrometer. 68 » ~\ : tr Doh a9 Oao wo Oe eH Om = Om On te mt be oon w we ow GOD G2 m wd on Noaomnwowoconu ns to 29 Weather. Fair Cloudy Rain Cloudy Fair Rain Cloudy Rain Fair Fair Cloudy Stormy Fair Cloudy | Fair : Fair Fair Stormy Stormy Rain {Fair Fair Fair Cloudy FAME Yel Fair Mth Showery, with high wind at night . Showery Cloudy. High wind and raim at night Fair N.B. The Barometer’s height is taken at one o’clock. ° Ce teeter ie ae aE i a \ XVI. Observations on Architecture. : To Mr. Tilloch. SIR, © has been observed, that ‘we are better painters and worse architects than our neighbours the French :” but I presume, that, of our architectural ability, it is difficult to form adequate notions ; because in England many of the:best Specimens are distributed about the country, and there- fore too far removed from each other to forma grand whole whereas the contrary is the case in France. There, the go- vernment does every thing, and the individual scarcely any thing; her architecture is consequently more public. Hence, perhaps, it is that those who visit France, and compare the talents of her architects with our own, forget the praise which is due to England, where almost every thing is done by the individual, and comparatively nothing by the govern- ment. That therefore which is done by him must be some- what limited ;. for it is by public works alone that real splen- dour can be exhibited 3 in architecture. Its operations are too expensive for individual accomplishment, ‘and of course be- yond the reach of that patronage which'1s, and has been, extended to its promotion elsewhere. Is it. then to be in- ferred, because there is a poverty of public patronage, that our architects want talent? Certainly not !—let them be sure of employ, if they excel in taste, and‘no comparison — tending to raise one art at the expense of another, will be regarded. Whether the present times, which are warm in the patronage of painting, will give rise to more hberal no- tions in architecture, cannot yet be known; but, at any rate, there will be found no want of talent in this latter branca of t, if a sufficient stimulus arises adequately to employ . Bis our neighbours say, that ** we have no taste for design 3’ and they refer our supposed want of it to national causes. — It would be singular indeed if we, who excel in poetry, in painting, and in sculpture, {who even equal the antients in these arts, if originality {be admitted as the claim to equa- - lity,) should in desigm be defective :—It will naturally be asked, Does it require more abilities to excel in design, than “Nol, 32, No. 126. Now. 1808, G in 98 Observations on Architecture. in the praciiee of the other arts ?—No! the greatest pro fessors of them all have been also the greatest designers. Is it not then fair to infer, that they who have excelled in the one would likewise excel in the other if equally employed ? If these assumptions be. admitted, the conclusion 1s, that our supposed inferiority in this art is not to be at- tributed to “national eauses,’’ or to “ want of talent,” but to the absence of national discernment, which creates dis- gust, aid neglects to distinguish those who by their taste deserve public patronage. The French excel us in this discernment (if any judgement can be justly formed of their new buildings); and this assertion will be borne out by all who have had an opportunity of viewing their capital during the peace of Amiens. A Gallery-advocate may perhaps answer, ‘* And do not our nobility, to whom the arts alone can look for patronage, extend it liberally? Have they not ’ established a British Institution ; and do they not by their nianificence add a real value to us establishment, by select- ing and purchasing the best performances that are therein exhibited?” Granted :——But this has advanced one or two branches of art only ; and has left the arehitect, whose ad- vauceinent forms the purpose of this paper, in a state of total neglect. No reflection can attach to the institution; it has done immense service to: the arts; and it is only re- yretted, that, from the known liberality of its promoters, they should not have adopted some mode of giying. equal encouragement to archiiecture. At Aghens, the birth-place of the arts, architecture stood . the first in importance, as it didin perfection and glory :—to expect Athenian encouragement in England may appeat vain; but it is‘a species of vanity which some have cherished, and many expected to realize when that noble establishment was first formed.—The beauties of this art are not confined tothe operations of the mere rule and compass, as some have ima- gined ; nor are her greatest attributes, the orders, formed to arbitrary proportions, as some have asserted. It would be difficult indeed to fix on what those proportions consisted; for in all the remains of antiquity no two are found to be-exaetly similar ; the required purpose alone directed the architect in . the Olservations on Architecture. 99 the choice of his column. At Athens, for instance, the columns of the Parthenon, of Minerva, and of Theseus, all differ, though the attributes of the several classes remain : and the same may be observed of other remains. At the restoration of the art, Italy abounded in splendid relics, which furnished the restorers with models ; hence arose the notions of seven, eight, and nine diameters to express the proportions of the several orders, Doric, Tonic, and Co- rinthian ; which, having been published, spread soon through the other nations of Christendom. Now, as it fell.to the lot of more persons to see the copies than the originals, that proportion was received for certain, which had been adapted for convenience only. From such copies have all the arbitrary notions concerning architecture been derived. Books after -books *, with various high-sounding titles, had issued from the press, all setting forth the hoasted proportions: hence the principles of the art became degraded to a mere wnder- standing of the division of the parts ; and in this state it re- mained till travel and study developed the source from which autient architecture emanated. And let it ever he recorded to the honour of the society called Dilettanto, and to their travellers Stuart and Reveley, that tothem England, nay Europe, is indebted for the genuine representation of Grecian architecture. However glorious for the art the disclosure of the Grecian remains might have been, some, bigoted to the Roman manner, vented their zeal by denying their accuracy: but as truth and beauty are superior to error ‘and deformity, so have they risen above the prejudice of their opponents. : In England, every thing is said to be a@ speculation ; and with respect to the arts, in general, it has in truth been too much so: by the prevalence of this spirit they have suf- fered even more than by caprice. Speculation has made many of their professors intent more upon riches than emi- nence. The glory of their art has been thus perverted, and its legitimate purpose prostituted ; nor has architecture suf- * « Were a modern architect,” says Hogarth, “to build a palace in Lap- land, or the West Indies, Palladio must be his guide; nor would be dare to stir a step without his book.” Ge : fered 100 Observations on Architecture. fered less than the sister arts. Such has been the perversion in this art, to which its professors have contributed largely, that our villas, mansions, &c., have been metamorphosed 5 and, in too many instances, columns have been dismantled and entablatures overthrown, to be replaced by a battle- mented pofch, a tower, or some other device from a Gothic model. By this demon of innovatiow have some of our most regular structures been destroyed; and others con- tinue to be destroyed, to place tm their stead a melange style, adapted neither to give comfort nor elegance to the habitation , of man. That such a fashion should obtain a footing in our island at the present period of mental improvement, is not to be accounted for upon the common principles of human measurement. That our nobility, who affect to admire every thing that is Grecian, should, instead of encouraging classic architecture, surround themselves with pinnacles and stained glass, the emblems of superstition and igne-. rance, (and with these, ton, of the most stupid and clumsy wnitation, without pretension to the character or chasteness of the original,) will be viewed, it ts to be hoped, with astonishment at a period not very remote. Good taste has: its foundation in good sense; but there is not much of either jn giving to a modern gentleman’s residence the form of an abbey or of a castle :—fitness should be the end; but this practice stands opposed to it, for that cannot be fit- ness which erects towers and constructs forts, where nei- ther protection nor observation are necessary or anticipated. A statistical writer, speaking of this practice, says, he « would suggest the impropriety of making a house or any o:her object bear an outward appearance intended to contra- dict. its inward use ; all castellated or gothicised houses, all church-like barns, or fort-like pig-styes, he should eon- ceive to be objectionable: they are intended to deceive, and they tell you that they are intended to deceive.” It is from such practice as this, without principles, and consequently capricious, that avchitecture has fallen, not only in com- parison. with the sister arts, but likewise in public estima- tion; and it will continue so to do until its professors ainr at 2 reputation more lasting than can be obtained. by such P _incon- © On the Decomposition and Composition of the Alkalis. 101 mconsistencies. It is seriously to be hoped, as research has developed abundant examples of antient art, that those ex- amples which contain what is useful, chaste, and elegant, will prevail among a people not less distinguished for ‘their taste than their erudition 3 and that the architect, trué to the genuine purpose of his art, will consider an Herculaneum and a Pompeii as containing stores whereby his reputation may be raised on surer ground, than on the imitation of forts and towers. J. ee XVII. The Bukerian Lecture, on some new Phenomena of Chemical Changes produced by Electricity, particularly the Decomposition of the fixed Alkalis, and the Exhibition of the new Substances which constitute their Bases; and on the general Nature of alkaline Bodies. By Homeury Davy, Esq., Sec. R.S. ARAL A. e {Continued from p. 18.] V. On the Properties and Nature of the Basis of Soda. ae basis of soda, as I have already mentioned, is a solid at common temperatures. It is white, opaque, and when examined under a film of naphtha has the lustre and gene- ral appearance of silver. [t is exceedingly malleable, and is much softer than any of the common metallic substances. When pressed upon by a platina blade, with a small ee it spreads into thin leaves, and a globule of the th or 55th ‘of an inch in diameter is easily spread over a surface Jos quarter ef an inch*, and this property does: not diminish when it 1s cooled to 32° Fabrenheit. It conducts electricity and heat in a similar manner to the basis of potash; and small globules of it inflame by the voltaic electrical spark, and burn with bright explosions. Its specific gravity is less than that of water. It swims in oil of sassafras of 4:096, water being one, and sinks in * GClobules may be easily made to adhere and form one mass by strone pressure: so that the property of welding. which belongsto iron and platina at 2 white heat only, is possessed by this substance at common temperatures. G3 naphtha 102 On the Decomposition and Composition naphtha of specific gravity -861. This circumstance dialed me to ascertain the point with precision. 1 mixed together oil of sassafras and naphtha, which combine very perfectly, observing the proportions till I had composed a fluid, in which it remained at rest above or below; and this fluid consisted of nearly twelve parts naphtha, and five of oil of sassafras, which gives a specific gravity to that of water, nearly as nine to ten, or more accurately as °9348 to 1. The basis of soda has a much higher point of fusion than the basis of potash ; its parts begin to Jose their cohesion at about 120° Fahrenheit, and it is a perfect fluid at about 180°, so that it readily fuses under boiling naphtha. I have not yet been able to ascertain at what degree of heat it is volatile; butit remains fixed ina state of ignition at the point of fusion of plate glass. The chemical phenomena produced by the basis of sada, are analogous to those produced by the basis of potash; but with such characteristic differences as ntight be well expected. When the basis of soda is exposed to the atmosphere, it immediately tarnishes, and by degrees becomes covered with a white crust, which deliquesces much more slowly than the substance which forms on the basis of potash. It proves, on minute examination, to be pure soda. The basis of soda combines with oxygen slowly, and without luminous appearance at all common temperatures ; and when heated, this combination becomes more rapid ; but no light is t ratted till it has acquired a temperature nearly that of ignition. The flame that it produces in oxygen gas is white, and it sends forth bright sparks, occasioning a very beautiful effect; in common air, it burns with light of the colour of that produced during the combustion of charcoal, but much brighter. The basis of soda when heated in bydvagen seemed to have no action upen it. When introduced into oxymuriatic atid gas, it burnt vividly with numerous scintillations of a bright red colour. Saline matter was formed in this com- bustion, which, as might have been expected, aah: to be muriate of soda. of the fred Alkalis. 108 its operation upon water offers most satisfactory evidence of its nature. When thrown upon this fluid, it produces a violent effervescence, with a loud hissing noise; it combines with the oxygen of the water to form soda, which is dis- solved, and its hydrogen is disengaged. Tn this operation — there is no luminous appearance ; oa it seems probable that even im the nascent state hydrogen is ee of combining with it*, When the basis of soda is thrown into het water, the de- composition is mere violents and in this case a few scintil- Jatiens are generally observed at the surface of the fluid; but — this is owing to small particles of the basis, which are thrown out of the water sufficiently heated, to burn in pass- ing through the atmosphere. When, however, a globule is brought in contact with a small particle of water, or with moistened paper, the heat produced (there being no medium to carry it off rapidly) is useally sufficient for the accension of the basis. The basis of soda acts upon alcohol and ether precisely in a similar manner with the basis of potash. The water that they contain is decomposed; soda is rapidly formed, and hydrogen disengaged. : The basis of soda, when thrown upon the strong acids, acts upon them with great energy. When nitrous acid is employed, a vivid inflammation is produced ; with muriatie. and sulphuric acid, there is much heat generated, but no light. : When plunged, by proper means, beneath the surface of the acids, it is rapidly oxygenated; soda is produced, and the other eduets are similar to those generated by the action ef the basis of potash. With respect to the fixed and volatile oils and naphtha j in their different states, there is a perfect coincidence between the effects of the two new substances, except im the dif- ference of the appearances of the saponaceous compounds formed: those produced by the oxidation and combination * The more volatile metals only seem capable of uniting with hydrogen: 4 circumstance presenting an analogy. G4 of ~ 104 _ On the Decomposition and Composition of the basis of soda being of a darker colour, and Basan less soluble. * The basis of soda, in its degrees of hers has. pre- cisely similar habits with the basis of potash. When it is fused with dry soda, in certain quantities, there is'a division of oxygen between the alkali and the base ; and a deep brown fluid is produced, which becomes a dark gray solid on cooling, and which attracts oxygen from the air, or.which decomposes water, and becomes soda. The same body is often formed in the analytical processes: of decomposition, and it is generated when the basis of soda is fused in tubes of the purest plate glass. There is scarcely any difference in the visible phenomena of the agencies of the basis of soda, and that of potash om sulphur, phosphorus, and the metals. It combines with sulphur in close vessels filled with the vapour of naphtha with great vividness, with light, heat, and often with explosion from the vaporization of a por- tion of sulphur, and the disengagement of sulphuretted hy- drogen gas. The sulphuretted basis of soda is of a deep gray colour. The phosphuret has the appearance of lead, and forms phosphate of soda by exposure-to air, or by combustion. The basis of soda in the quantity of 7, renders mercury a fixed solid of the colour of silver, and the combination is attended’with a considerable degree of heat. It makes an alloy with tin, without changing its colour, and it acts upon lead. and gold when heated. I have not examined its habitudes with any other metals, but in its ‘state of alloy it is soon converted into soda by exposure to air, or by the action of water, which it died skal with the evolution of hydrogen. The amalgam ait mercury and the basis of soda seems to forma triple comipotinds with other metals. I have tried iron and platina, which Iam inclined to believe remain in com- bination with the mereury, when it is deprived of the new substance by exposure to air. The amaigam of the basis of soda and mercury Fipsee combines of ihe fixed Alkalis. 105 eombines with sulphur, and forms a triple compound of a dark gray eolour. VI. On ue Proportions of the peculiar Bases and Oxygen in Potash and Soda. The facility of combustion of the bases of the alkalis, and the readiness with which they decomposed water, offered means fully adequate for determining the proportions of their ponderable consiituent parts. I shall mention the general methods of the experiments, and the results obtained by the different series, which ap- proach as near to each other as can be expected in operations performed on such small quantities of materials. For the process in oxygen gas, | employed glass tubes containing small trays made of thin leaves of silver or other noble aay on, which the substance to be burnt, after being accurately weighed or compared with a globule of mercury, equal in size *, was placed: the tube was small at one end, curved, and brought to a fine point, but suffered to remain open; and the other end was fitted to a tube come municating with a gasometer, from which the oxygen gas was introduced, for neither water nor mercury could’ be used for filling the apparatus. The oxygen gas was carried through the tube till it was found that the whole of the com- mon air was expelled. The degree of its purity was ascer- tained by suffering a small quantity to pass into the mer- curial apparatus. The lower orifice was then hermetically sealed by a spirit lamp, and the upper part drawn out and finally closed, when the aperture was so small, as to render the temperature employed incapable of materially influencing the volume of the gas; and when the whole arrangement was made, the combination was effected by applying heat to the glass in contact with the meiallic tray. In performing these experiments’ many difficulties oc- * When the globules were very small, the comparison with mercury, which may be quickly made by means of a micrometer, was generally em- ployed 2s the means of ascertaining the weight : for in this case the globule could be immediately introduced into the tube, and the weight of mercury ascertained at leisure. . curred, - 6 . Onthe Decomposition and Composition curred. When the flame of the lamp was immediately brought to play upon the glass, the combustion was very vivid) So as sometimes to break the tube; and the alkali ge- nerated partly rose in white fumes, which were deposited upon the glass. When the tenrperature was aeuly raised, the bases of the alkalis acted upon the metallic tray and formed alloys, and ' in this state it was very dificult to combine them with their full proportion of oxygen; and glass alone could not be- employed on account of its decomposition by the alkaline bases ; and porcelain is so bad a conductor of heat,, that it was not possible to raise it to.the point required for the pro- cess, without softening the glass. In all cases the globules of the alkaline bases were care-_ fully freed from naphtha before they were introduced; of course a slight crust of alkali was formed before the com- bustion, but this could not materially affect the result; and when such a precaution was not used, an explosion gene- tally took place from the vaporization od decomposition of the film of naphtha surrounding the globule. After the combustion, the absorption of gas was ascer- tained, by opening the lower point of the tube under water orthercury. In some cases the purity of the residual air was ascertained, in others the alkali formed in the tray was weighed, From several experiments on the synthesis of potash by combustion, I shall select two, which were made with every possible attention to accuracy, and under favourable circum= stances, for a mean result. In the first experiment 0:12 grains of the basis 1 were em- Joyed. The combustion was ee upon platina, and was rapid and complete; and the basis appeared to be perfectly saturated, as no disengagement of hydrogen took place when the platina tray-was thrown into water. The oxygen gas absorbed equalled in volume 190 grain measures of quick- silver ; barometer being at 29°6 inches, thermometer 62° Fahrenheit ; and this reduced to a temperature of 60° Fahr- enheit, and under a pressure equal to that indicated by 30 | inches, - of the fixed Alkalis. 107 inches *, would become 186°67 measures, the weight of which would be about '01$¢ grains troy f, but°0184: °1364:: 13°29: 100; and according to this estimation 100 parts of potash will consist of 86-7 basis, and 13°3 oxygen nearly. In the second experiment ‘07 grains of the basis absorbed at temperature 63° of Fabrenheit, and under pressure equal to 30°! barometer inches, a quantity of oxygen equal in volume to 121 erain measures of mercury, and the proper corrections being made as in the former case, this gas would weigh :01189 grains. But as :07 + °01189 = *08189: 07 :: 100: 85°48 nearly, and 100 parts of potash will consist of 85:5 of basis and 14:5 of oxygen nearly. And the mean of the two experl- ments will be 867i of basis to 13-9 of oxygen for 100 parts. In the most accurate experiment that I made on the com- bustion of the basis of soda ‘68 parts of the basis absorbed a quantity of oxygen equal to 206 grain measures of mer- cury; the thermometer being at 56° Fahrenheit ; and the barometer at 29°4; and this quantity, the corrections being made as before for the mean temperature and pressure, equals about *02 grains of oxygen. And as °08 + 02 = '10: °08, :: 100: 80, id 100 parts of.soda according to this estimation will consist of 80 basis to 20 of oxygen. In all cases of slow combustion, in wach the alkalis were not carried out of the tray, I found a considerable increase > of weight; but as it was impossible to weigh them except in the atmosphere, the moisture attracted rendered the results doubtful; and the proportions from the weight of the oxy- gen absorbed are more to be depended on, In the experi- ments in which the processes of weighing were most speedi- - * In the correction for temperature, the estimations of Dalton and Gay Lussac are taken, which make gases expand about 71; of the primitive _VO- lume for every degree of Fahrenheit. + From experiments that I made in 1798, on the specific gravity of oxypeu gas, it would appear that its weight is to that of water as 1 to 748, and te that of quicksilver as 1 to 10142. Researches Chem, and Phil. p. 9; and with this estimation, that deducible from the late accurate researches of Messrs, Allen and Pepys on the Combustion of the Diamond almost precisely agrees, Phil. Trans. 1807, p. 272, ly i108 - On the Dosadts tor and Composition ly performed, and in which no alkali adhered to the tube, the basis of potash gained nearly two parts for ten, and that of soda between three and four parts. The results of the decomposition of water by the bases of the alkalis were much more readily and perfectly obtained than those of their combustion. To check the rapidity of the process, and, in (Me case of | potash, to prevent any of the basis from being dissolved, I employed the amalgams with mercury. IT used a known weight of the bases, and made the amalgams under naph- sie using about two paris of mercury in volume to one o: basis. In the first instances I placed the amalgams under tubes filled with naphtha, and inverted in glasses of naphtha, and slowly admitted water to the aes at the bottom of the glass ; ; but this precaution I soon round unnecessary, for the action of the water was not so intense but that the hydrogen gas could be wholly collected. A I shall give an account of the most accurate experiments made on the decomposition of water by the bases of potash and soda. In an experiment on the basis of potash conducted with every attention that I could pay to the minutiz of the ope- rations, hydrogen gas, equal in volume to. 298 grains of mercury, were disengaged by the action of :03 grains of the basis of potash eukieht had been deal aiaatetl with about three grains of mercury. The dhenmditicter at the end of the process indicated a temperature of 56°? Fahrenheit, and the barometer an atmospheric pressure equal to 29°6 inches. Now this quantity of hydrogen* would require for its combustion a volume of oxygen gas about equal to that oc- cupied by 154°9 grains of mercury, which gives the weight of oxygen required to saturate the -08 grains of the basis of potash at the mean temperature and pressure nearly ‘0151 grains. And ‘08 + 0151 =°0951:°08: : 100: 84:1 nearly. And according to these indications 100 parts of potash | consist of about 84 basis and 16 oxygen. * Researches Chem. and Phil. page 287. In of the fixed Alkalis. 109 Tn an experiment on the decomposition of water by the basis of soda, the mercury in the barometer standing at 30°4 inches, and in the thermometer at 52° Fahrenheit, the volume of hydrogen gas evolved by the action of 054 grains of basis equalled that of 326 erains of quicksilver. Now this at the mean temperature and pressure would require for its conversion into water, °0172 of oxygen, and +054 + “0172 = 0712 : 0542: 100: 76 nearly; and according to these indications, 100 parts of soda consist of nearly 76 basis, and 24 oxygen. Tn another experiment made with very great care, -052 of the basis of spda were used; the mercury in the barometer was at 29°9 inches, and that in the thermometer at 58° Fah- renheit. The yolume of hydrogen evolved was equal to that of 302 grains of mercury ; which would demand for its sa- turation by combustion, at the mean temperature and pres- sure, ‘01549 grains of oxygen; and 100 parts of soda, ac- cording to this proportion, would consist nearly\of 77 basis, and 23 oxygen. The experiments which Tava been just detailed, are those in which the largest'quantities of materials were employed ; I have compared their results, however, with the results of several others, in which the decomposition of water was performed with great care, but in which the proportion of the bases was still more minute: the largest quantity of ox- ygen indicated by these experiments was, for potash 17, and for soda 26 parts in 100, and the smallest 13, and 19; and comparing all the estimations, it will probably be a good approximation to the truth, to consider potash as composed of about six parts basis and one of oxygen; and soda, as consisting of seven basis and two oxygen. VII. Some general Observations on the Relations of the Bases of Potash and Soda to other Bodies. Should the bases of potash and soda be called metals? ‘The greater number of philosophical persons to whom this question has been put, have answered in the affirmative. They agree with metals in opacity, lustre, malleability, con+ ducting. le On the Decomposition and Composition ducting powers as to heat and electricity, and in their quali- ties of chemical combination. Their low specific gravity does not appear a sufficient rea- son for making them a new class; for amongst the metals themselves there are remarkable differences in this respect, platina being nearly four times as heavy as telluriam*; and in the philosophical division of the classes of bodies, the _ analogy between the greater number of properties must al- ways be the foundation of arrangement. On this idea, in naming the bases of potash and soda, it will be proper to adopt the termination which, by common consent, has been applicd to other newly discovered metals, and which, though orig:nally Latin, is now naturalized in our language. Potasium and sodium are the names by which I have ven- tured to call the two new substances: and whatever changes of theory, with regard to the composition of bodies, may - hereafter take place, these terms can scarcely express an error; for they may be considered as implying simply the metals produced from potash and soda. 1 have consulted with many of the most eminent scientific persons in this country, upon the methods of derivation, and the one I have adopted has been the one most generally approved. . It is perhaps more significant than elegant. But it was not possible to found names upon spec:fic properties not com- mon to both ; and though.a name for the basis of soda might have been borrowed from the Greek, yet.an analogous one could not have been applied to that of potash, for the an- tients do not seem to have distinguished between the two alkalrs. The more caution is necessary in avoidipg any theoretical expression in the terms, because the new eco chemical phenomena that are daily becoming disclosed, seem di- * Tellurium is not much more than six times as heavy as the basis of soda. There #5 great reason to believe that bodies of a similar che:nical nature to the bases of potash and soda will be found of intermediate specific gravities between them and the lightest ofthe common metals. Of this subject I shall treat again in the text in some of the following pages, - . stinctly. ae ite AP of the fixed Alkalis. st ee stinctly to show that the mature time for a complete gene- ralization of chemical facts ts yet far distant; and though, in the explanations of the various results of experiments that have been detailed, the antiphlogistic solution of the pha- nomena has been uniformly adopted, yet the motive for employing it has been rather a sense of its beauty and pre- cision, than a conviction of its permanency and truth. The discovery of the agencies cf the gases destroyed the hypothesis of Stahl. The knowledge of the puwers and effects of the ethereal substances may at a future time pos- sibly act a similar part with regard to the more refined and ingenious hypothesis of Lavoisier; but in the present state of our knowledge, it appears the best approximation that has been made to a perfect logic of chemistry. Whatever future changes may take place in theory, there seems however every reason to believe that the metallic bases of the alkalis, and the common metals, will stand in the same arrangement of substances; and as yct we have no good reasons for assuming the compound nature of this class of bodies *. The experiments in which it is said that alkalis, metallic oxides, and earths may be formed from air and water alone, in processes of yegetation, have been always made in an in- conclusive manner; for distilled water, as | have endea- voured * A phiogistic ehemical theory might eertainly_be defended, on the idea that the metals are compounds of certain unknown bases with the same mat~ ter as that existing in hydrogen; and the metallic oxides, alkalis and acids compounds of the same bases with water ;—but in this theory more unknowe principles would be assumed than in the generally received theory. It would be less elegant and less distinct. In my first experiments on the distillation of the basis of potash finding hydrogen generally preduced, I was led to com- pare the phlogistic hypothesis with the new facts, and I found it fully ade- quaie to the explanation. More delicateresearches however aficr wards proved that in the cases when inflammable gases appeared, water, or some body in which hydrogen is admitted to exist, was present. + The explanation of Van Helmont of his fact of the production of earth m the growth of the willow, was completely overturned by the researches of Woodward. Phil, Trans. vol. xxi. p. 193. ee The corciusions which M. Braconnot has very lately draven from his in. genious experiments, Annales de Chimie, Wevrier 1807, p. 187, are rendered of little avail in consequence of the circumstances stated in t xt. In theoaly ra 87 3 case 112 On the Decomposition and Composition of the Alkalis. voured to show *, miay contain both saline and metallic im- pregnations 5 and the free atmosphere almost constantly olds in mec chanical suspension solid Sees of various dems .4:')%a hat + ‘In,the.common processes:of 1 Rouges all. thie: pioducts of Jiving beings may be easily conceived to be elicited from know abe of matter. The compounds of iron, of the alkalis, and earths, with mineral acids, generally abound in soils. From the decomposition of basaltic, porphyritic F5 and granitic rocks, there is a-constant supply of earthy al- kaline and ferruginous materials to the surface of the earth. In the sap of all plants ihat have been examined, certain neutrosaljne compounds, containing potash, or soda, or iron, have been found. From plants they may be supplied to animals. And the chemical tendency of organization: seems to be rather to combine substances nto more compli- cated and diversified arrangements, than to reduce them into simple elements. " case of vegetation in which the free atmosphere was excluded, the seeds grew in white sand, which is stated to have been purified by washing in muriatic acid; but such a process was insuflicient to deprive it of substances which might afferd carbon, or various inflammable matters. Carbonaceous matter exists in several stones which afford a whitish or grayish powder; and when in a stone the quantity of carbonate of lime is very small in proportion to the other earthy ingredients, it is scarcely acted on by acids, * Bakerian Lecture, 1806, page 8. + In the year 1804, for a particular purpose of geological inquiry, I made an analysis of the porcelain clay of St. Stevens, in Cornwall, which results. from the decomposition of the feldspar of fine‘grained granite. ~I could not ‘detect init the smallest quantity of alkali. - In making some experiments on specimens of the undecompounded rock taken from beneath the surface, there were evident indications of the presence.of a fixed alkali, which seemed to be potash. So that it is very probable that the decomposition depends on the operation of water and the carbonic acid of the atmcsphere on the alkali forming a constituent part of the crystalline matter of the feldspar, which may Serer from being deprived of it. {To be continued.] : AT Res oh A bao XVIII. An Account of the Application of the Gas from Coal to economical Purposes. By Mr. WittiaAM Murpocu. Communicated by the Right Hon. Sir Josuru BANKS, Bart. K.B. PRS Tax facts and results intended to be communicated in this paper, are founded upon observations made, during the pre- sent winter, at the cotton-manufactory of Messrs. Philips and Lee at Manchester, where the light obtained by the combustion of the gas from coal is used upon a very large scale; the apparatus for its production and application having been prepared by me at the works of Messrs. Boul- ton, Watt, and Co., at Soho. The whole of the rooms of this cotton-mill, which is, I believe, the most extensive in the united kingdom, as well as its ccounting-houses and store-rooms,. and the adjacent _dwelling-house of Mr. Lee, are lighted with the gas. from coal. The total-quantity of light used during the hours of © burning, has heen ascertained, by a comparison of shadows, to be about equal to the light which 2500 mould candles of six in the pound would give; each of the candles, with which the comparison was made, consuming at the rate of 4-10ths of an ounce (175 grains) of tallow per hour. The quantity of light is necessarily liable to some varia-- tion, from the difficulty of adjusting all the flames, so as to be perfectly equal at all times; but the admirable pre- cision and exactness with which the business of this mill is conducted, afforded as excellent an opportunity of making the comparative trials I had in view, as is perhaps likely to be ever obtained in general practice. And the experiments being made upon so large a scale, and for a considerable period of time, may, I think, be assumed as a sufficiently accurate standard for determining the advantages to be ex- - pected from the use of the gas lights under favourable cir- cumstances. It is not my intention, in the present paper, to enter into ‘ * From Philosophical Transactions for 1808, Fart L Vol. 32. No. 126, Nov, 1808. EL a par- 114 On the Application of the Gas from Coal. a particular description of the apparatus employed for pro ducing the gas; but J may observe generally, that> the ‘coal is distilled in large iron retorts, which during the winter season are kept constantly at. work, except during the in- tervals of charging ; and that the gas, as it rises from them, is conveyed by iron pipes into large reservoirs, or gasome= ters, where it is washed and purified, previous to its being conveyed through other pipes, called mains, to the mill. These mains branch off into a variety of ramifications (form- ing a total length of several miles), and diminish in size, as the quantity of gas required to be passed through them be-' comes less. The burners, where the gas is consumed, are connected with the above mains, by short tubes, each of which is furnished with a cock to regulate the admission of the gas to each burner, and to shut it totally: off when re- quisite: This Jatter operation may likewise be instantane- ously performed, throughout the whole of the burners in each room, by turning a cock, with which each main is provided, near its entrance into the room. — The burners are of two kinds; the one is upon the sue ciple of the Argand lamp, and resembles it in appearance ; the other is a smal! curved tube with a conical end, having three circular apertures or perforations, of about a thirtieth -of an inch in diameter, one at the point of the cone, and two lateral ones, through which the gas issues, forming three divergent jets of flame, somewhat like a fleur-de-lis. The shape and general appearance of this tube has pro- cured it, among the workmen, the name of the cockspur burner. . The number of burners employed in all the buildings amounts to 271 Argands, and 633 cockspurs ; each of the former giving a light equal to that of four candles of the de- scription above mentioned ; and each of the latter, a light equal to two and a quarter of the same candles; making — therefore the total of the gas light a little more than equal to that of 2500 candles. When thus regulated, the whole of the above burners require an hourly supply of 1250 cubic feet of the gas produced from cannel coal; the superior apalty On the Application of the Gas from Coal. 113 quality and quantity of the gas produced from that material having given it a decided preference in this. situation, over every other coal, notwithstanding its higher price. The time during which the gas light is used, may, upon an average of the whole year, be stated. at least at two hours per day of twenty-four hours. In some mills, where there is over work, it will be three hours; and in the few where night-work is still continued, nearly, twelve hours. But taking two hours per day as the common average throughout the year, the consumption in Messrs. Philips’ and Lee’s mill will be 1250 x 2 = 2500 cubic feet of’ gas per day ; to produce which, seven hundred weight of cannel coal is required in the retort. The price of the best Wigan cannel (the sort used) is 13!d. per cwt. (29s. 6d. per ton), deli- vered at the mill, or say about eight shillings for the-seven hundred weight. Multiplying by the number of working days in the year (313), the annual consemption of cannel will be 110 tons, and its cost 125d. About one-third of the above quantity, or say forty tons of good common coal, value ten shillings per ton, is re-_ quired for fuel to heat the retorts; the annual amount of which is 20/. ‘The 110 tons of cannel coal, when distilled, produce about 70 tons of good coak, which is sold upon the spot at 1s. 4d. per cwt. and will therefore amount annually to the sum of 93/. The quantity of tar produced from each ton of cannel coal is from eleven to twelve ale gallons, making a.total annual produce of about 1250 ale gallons, which not having been yet sold, I cannot determine its value; but whenever it comes to be manufactured in large quantities, it cannot be such as materially to influence the ceconomical statement, unless indeed new applications of it should be discovered. The quantity of aqueous fluid which came over in the course of the observations which I am now giving an ac- count of, was not exactly ascertained, from some springs having got into the reservoir; and as it has not been yet ap- plied to any useful purpose, I may omit further notice of it in this statement. H 2 The 116 On the Application of the Gas from Coal. The interest of the capital expended in the necessary ap- paratus and” buildings, together with what is considered as an ample allowance for wear and tear, is stated by Mr. Lee at about 550/. per annum: in which some allowance is made for this apparatus being made upon a scale adequate to the supply of a still greater quantity of Pest than he has occa- , sion to make use of. He is of opinion, that the cost of attendance upon candles would be as much, if not more, than upon the gas appa- ratus; so that in forming the comparison, nothing need be stated upon that score, on either side. The cecortomical statement for one year then stands thuss° . Cost of 110 tons of cannel coal - 1251, Ditto of 40 tons of common ditto - 20 145 Deduct the value-of 70 tons of coak - 93 The annual expenditure in coal, after deduct- ing the value of the coak, and without allow- ing any thing for the tar, is therefore - 42 And the interest of capital, and wear and tear of apparatus - - - - - 550 making the total expense of the gas apparatus, about 600l, per annum. That of candles, to give the-same light, would be about 2000/. For each candle consuming at the rate of 4-10ths of an ounce of tallow per hour, the 2500 eandles burning upon an average of the year two hours per day, would, at one’ shilling per pound, the present price, amount to fe the sum oF money above mentioned. If the comparison were made upon an ayerage of three hours per day, the advantage would be still more in favour of the gas light ; the interest of the capital, and wear and ~ tear of the apparatus continuing nearly the same as in the former case ; thus, 1250 x 3. = 3750 cubic feet of gas per day, which would be produced by 103. cwt. of cannel coals; this multiplied by : the © On the Application of the Gas from Coal. 117 the number of working days, gives 168 tons per annum, which, valued as before, amounts to - 1882, ~ And 60 tons common coal for burning under the retorts, will amount to - - 30 218 Deduct 105 tons of coak at 26s. 8d. - 140 Leaving the expenditure in coal, after deduc- tion of the coak, and without allowance for / the tar, at - - - - 78 Adding to which the interest and wear and tear of appara- tus, as before, the total annual cost will not be more than 650/., whilst that of tallow, rated as before, will be 3000/. It will readily occur, that the greater number of hours the gas is burnt, the greater will be its comparative ceconomy $ although in extending it beyond three hours, an increase of some parts of the apparatus would be necessary. If the ceconomical comparison were made with oils, the advantages would be less than with tallow. The introduction of this species of light into the establish- _ment of Messrs. Philips and Lee, has been gradual; be- ginning in the year 1805, with two rooms of the mill, the counting-houses, and Mr. Lee’s dwelling-house. After which, it was extended through the whole manufactory, as expeditiously as the apparatus could be prepared. At first, some inconvenience was experienced from the smell of the anconsumed, or imperfectly purified gas, which may in a great measure be attributed to the introduction of successive improvements in the construction of the appa- ratus, as the work proceeded. But since its completion, and since the persons to whose care it 1s confided have be- come familiar with its management, this inconvenience has been obviated, not only in the mill, but also in Mr. Lee’s house, which is most brilliantly illuminated with it, to the | - exclusion of every other species of artificial light. The peculiar softness and clearness of this light, with its almost unvarying intensity, have brought it into great fa- your with the work people. And its being free from the H3 incon- 118 On the Application of the Gas from Coal. inconvenience and danger, resulting from the sparks and freqvent snuffing of candles, is a circumstance: of material importance, as tending to diminish tie hazard_of fire, to which cotton mills are known to be much exposed. The above particulars, it is conceived, contain such ine - formation, as may tend to illustrate the general advdntages- attending the use of the gas light; but nevertheless the Royal anon may perhaps not dees it uninteresting to be » apprized of the circumstances which originally gave rise in mny mind to its application, as an ceconomical substitute for oils and tallow. ‘Tt is now nearly sixteen years, since, in a course of ex- periments I was making at Redruth in Cornwall, upon the quantities and qualities of the gases produced by distillation from different mineral and vegetable substances, I was in- duced by some observations I had previously made upon the burning of coal, to try the combustible property of the gases produced from it, as well as from peat, wood, and other inflammable substances. And being struck with the great quantities of gas which they afforded, as well as with the’ brilliancy of the light, and the facility of its production, I instituted several experiments with a view of ascertaining the cost at which it might be obtained, compared with that of _ egual quantities of light yielded by oils and tallow... _ My apparatus consisted of an iron retort, with tinned copper and iron tubes through which the gas was conducted to a.considerable distance ; and there, as well as at inter- mediate points, was burned through apertures of varied forms and dimensions. The experiments were made upon coal of different qualities, which I procured from distant parts of the kingdom, for the purpose of. ascertaining which © would give the most ceconomical results. The gas was also washed with water, and other means were employed to pu- rify it. In the year 1798, I remoyed from Cornwall to Messrs, Boulton, Watt, and Co.’s works for the manufactory of ‘steam engines at the Soho Foundry, and there I constructed an apparatus upon a larger scale, which during many suc- ; Cesslve ' Description of an improved Ship Stove. 119 cessive nights was applied to the lighting of their principal building, and various new methods were practised, of wash ing and purifying the gas. _ These experiments were continued with some interrup- tions, until the peace of-1§02, when a public display of this light was made by me in the illumination of Mr. Boulton’s manufactory at Soho, upon that occasion. Since that period, I have, under the sanction of Messrs. Boulton, Watt, and Co., extended the apparatus at Soho © Foundry, so as to give light to all the principal shops, where it is in regular use, to the exclusion of other artificial light ; but I have preferred giving the results from Messrs. Philips’ and Lee’s apparatus, both on account of its greater extent, and the greater uniformity of the lights, which rendered the comparison with candles less difficult. At the time I commenced my experiments, I was cer- tainly unacquainted with the circumstance of the gas frem coal having been observed by others to be capable of. com- bustion ; but I am since informed, that the current of gas escaping from Lord Dundonald’s tar ovens had heen fre- quently fired; and [ find that Dr. Clayton, in a paper in volume xli. of the Transactions of the Royal Society, so long ago as the year 1739, gave an account of some obser- vations and experiments made by him, which clearly mani- fest his knowledge of the inflammable property of the gas, which he denominates ‘¢ the spirit of coals ;”’ but the idea of applying it as an ceconomical substitute for oils and tallow does not appear to have occurred to this gentleman, and I believe I may, without presuming too much, claim both the first idea of applying, and the first actual application ef this gas to economical purposes. XIX. Description of an improved Ship Stove. y Mr. JoserH Couvier, of Crown-Street, Soho, London*. _ Vis stove is represented in the engraving PlateIV. Fig. 1. is the stove, with the front partly closed by the circular * From Transactions of the Society for the Encouragement of Arts, Manufac- _ ures, and Commerce, for 1807. Fifteen guineas were voted to Mr. Col- lier for this improvement, and a model is placed in the Society’s repdsitory. H 4 slide : " j 120 Preparing and apph ying a Composition for Painting slide A, which is moved from the back by the brass handle B. Ca moveable plate attached to’the slide A, now sup- ported by the latch catching a pin, by which means it acts” as a blower to cause the fire to burn more briskly, but which slides down also to shut the fire up. D another plate, now hanging on its Jatch, but which can be let down to shut up the ene -pit or dish I, which can be drawn out when the side facings FF are pulled up. Ga circular plate or cap, which slides so as to shut the chimney | up close. Fig. 2. The body of the stove with the slider A moved retin to the back, and thus leaving the fire-place com- pletely open. | Fig. 3. The ash-dish shown separate. Fig. 4. One of the side facings taken out to show the digided H, which slides into a bake made in the corner of the stove to hold it. The expense of one of these stoves of twelve inches di- ameter is about eight pounds. 1 XX. Method of preparing and applying a Composition for- Painting in Imitation of the Ancient Grecian Manner, called Encaustic Painting. a, Mrs. Hooxgr, of Rot~ tingdean, near Brighion*. Por into a glazed earthen vessel four ‘ounces and a half of gum arabic, and eight ounces (or half a pint wine mea- sure) of cold spring water ; when the gum is dissolved, stir _ in seven ounces of gum-mastich, w hich has been washed, ‘dried, picked, and beaten fine. Set the earthen vessel con- taining the gum-water, and gum-mastich, over a slow fire, continually stirring and beating them hard with a spoon, in order to dissolve the gum-mastich: when sufficiently boiled, it will no longer appear transparent, but will become opaque, and stiff, like a paste. As soon as this is the-case, and that the gum-water and mastich are quite boiling, without taking — them off the fire, add five ounces of white wax, broken into * From Transactions of the Society for the 5 ie ala oF cathe Manufac- tures, and Commerce, for 1807, 7 small in Imitation of the Ancient Grecian Manner. 121 small pieces, stirring and beating the different ingredients together, till the wax is perfectly melted and has boiled. Then take the composition off the fire, as boiling it longer than necessary would only harden the wax, and prevent its mixing so well afterwards with water. When the compo- ‘sition is taken off the fire, and in the glazed earthen vessel, it should be beaten hard, and whilst hot (but not bale) mix with it by degrees, a pint (wine measure) or sixteen ounces more of cold spring water, then strain. the compo- ‘sition, as some dirt will boil out of the gum-mastich, and put it into bottles : the composition, if properly made, should be like a cream, and the colours when mixed with it, as smooth as with oil. The method of using it, is to mix with the composition upon an earthen palette, such colours in powder as are used in painting with oil, and such a quantity of the composition to be mixed with the colours as to render: them of the usual consistency of oil colours; then paint with fair water. The colours when mixed with the compo- sition may be laid on either thick or thin, as may best suit your subject, on which account, this composition is very ’ advantageous, where any particular transparency of colour- ing is required; but in most cases it answers best, if the colours be laid on-thick, and they require the same use of the brush, as if painting with body colours, and the same brushes as used in oil painting. The colours if grown dry, when mixed with the composition, may be used by putting a little fair water over them; but it is less trouble to put some water when the colours are observed to be growing dry. In painting with this composition the colours blend ‘without difficulty when wet, and even when dry the tints — may easily be united by means of a brush and a very small quantity of fair water. When the painting is finished, put some white wax into a glazed earthen vessel over a slow fire, and when melted, but not boiling, with a hard brush cover the painting with the wax, and when cold take a moderately ° hot.ijron, such as is used for ironing linen, and so cold as not to hiss, if touched with any thing wet, and draw it . Jightiy over the wax. The painting will appear as if under a cloud till the wax is perfectly cold, as also, whatever the picturé \ - 322 Preparing and applying a Composition for Painting picture is painted upon is quite cold; but if, when so, the. painting should net appear sufficiently clear, it may be held before the fire, so far from it as to melt the wax but slowly; or the wax may be melted by holding a hot poker at such a distance as to melt it gently, especially such parts of the picture as should not appear sufficiently transparent or bril- ant; forthe oftemer heat is applied to the picture, the greater will be the transparency and brilliancy of colouring but the contrary effect would be produced if too sudden, or ioo great a degree of heat was applied, or for too long a time, as it would draw the wax too much to the surface, and might hkewise crack the paint. Should the coat of wax put over the painting when finished, appear in any part uneven 3 it may be remedied by drawing a moderatly hot iron over it again as before mentioned, or even by scraping the wax with a knife: and should the wax by too great or too long an application of heat form inio bubbles at particular places, by applying a poker heated, or even a tobacco-pipe made hot, the bubbles would subside ; or such defects may be removed by drawing any thing hard over the wax, which would close any small cavities. : When the picture is cold, rub it with a fine linen cloth. Paintings may be executed in this manner upon wood (hav- ing first pieces ‘of wood let in behind, across the grain of the wood to prevent its warping,) canvass, card, or plaster of Paris. The plaster of Paris would require no other prepa- ration than mixing some fine plaster of Paris in powder with cold water the thickness of a cream; then put it on a look- ing-glass, having first made a frame of bees-wax onthe Jooking-elass the form and thickness you would wish the plaster of Paris to be of, and when dry take it off, and there wil] be a very smooth surface to paint upon. Wood and canvass are best covered with some gray tint mixed with the same composition of gum-arabic, gum-mastich, and wax, and of the same sort of colours as before mentioned, beforé the design is begun, in order to cover the grain of the wood | or the threads of the canvas. Paintings may also be doné in the same manner with only gum-water and gum-mastichy | prepared the same way as the mastich and wax; but instead of iz Imitation of the Ancient Grecian Manner. 123 of putting seven ounces of mastich, and when boiling, adding five ounces of wax, mix twelve ounces of gum-mastich with the gum-water, prepared as mentioned in the first part of this receipt: before it is put on the fire, and when sufficiently boiled and beaten, and is a little cold, stir in by degrees “twelve ounces, or three quarters of a pint {wine measure) of cold spring water, and afterwards strain it. It would be equally practicable painting with wax alone, dissolved in gum-water in the following manner. Take twelve ounces or three quarters of a pint wine measure of cold spring water, and four ounces and a half of gum-arabic, put them into a - glazed earthen vessel, and when the gum is dissolved, add eight ounces of white wax. Put the earthen vessel with the gum-water and wax upon asiow fire, and stir them till the avax is dissolved and has boiled a few minutes: then take them off the fire and throw them into a bason, as by re- maining in the hot earthen vessel the wax would become rather hard ; beat the gum-water and wax till quite cold. As there is but a small proportion of water in comparison to the quantity of gum and wax, it would be necessary in mixing this composition with the colours, to put also some fair water. Should the composition be so made as to occasion the ingredients to separate in tne bottle, it will become equally serviceable if shaken before used to mix with the colours. I had lately an opportunity of discovering that.the com- position which had remained in a bottle since the year 1792, in which time it had grown dry and become as solid a sub- stamce as wax, returned to a cream-like consistence, and became again in as proper a state to mix with colours, as when it was first made, by putting a little cold water upon it, and suffering it to remain on a short time. J also lately found some of the mixture composed of only gum-arabic-_ water and gum-mastich, of which I sent a specimen to the Society of Arts m 1792; it was become dry, and had much she appearance and consistency of horn. I found, on letting some cold watery remain over it, that it became as fit for painting with, as when the composition was first prepared. Emma Jane Hooxer, : XXI. Essay - f 124 J XXI. Essay upon Machines in General. By M. Cannot, Member of the French ie Se. on | [Concluded from vol. xxxi. p- 305.} LXIIf. Oar remarks as to the momentum of activity, have originated an idea with me of a principle of equilibrium peculiar to the case where the forces exercised in the system are attractions: I think my readers will not be displeased to find it here; it is in the following terms: _ Several bodies subjected to the laws of .an attraction, ex- ercised in consequence of any function of distances, either by these bodies themselves upon each other, or by different fixed points being applied to any machine; if we make this ma- chine pass from any given position to that of equilibrium, the momentum of activity consumed in this passage by the atlractive forces with which these bodies will,be animated, during this movement, will be a maximum. That is to say, this momentum will be always greater than it would have been, if, instead of making this system pass to the position of equilibrium, we had constrained it to take a different route, and to pass into any other situation. For example, if gravity is the subject in question, which we may regard as an attraction exercised towards a point in- finitely removed, the attractive forces will be the weights applied to the machine:.the momentum of aetivity which will be exercised by these forces when we make this ma- chine change its situation, will therefore be equal to the total weight of the system multiplied by the height which the centre of gravity shall have descended or ascended du- ring this change of position (XXXII). Now the situation of equilibrium is that at which the centre of gravity is at the. highest or lowest point possible; therefore the height-to which the centre of gravity should ascend, or from which it should descend, in order to pass from any given situation to that of equilibrium, is greater than when it has to’ pass to any other situation: thus the momentum of activity con- sumed in the passage by the motrix forces, is also greater in the first case than in any other. ‘Tf . On Machines in General. - 125 If attraction was always constant like ordinary gravity, but, if directed towards a fixed point, placed at a finite distance, we might easily conclude from the preceding prin- ciple, that in the case of equilibrium, the sum of the mo- menta of the bodies of the system, relatively to this fixed point, is a maximum, 7. e. the sum of the products of each mass, by its distance to the fixed point, is less when there is an equilibrium, than if the system was placed in any -other given situation. If the attraction towards the fixed point, instead of being constant, was proportional to the distances from this body to this fixed point, we might conclude in the same way that the sum of the sree: of each mass by the square of the distance to this fixed point, is a maximum. We know that the sum of the products of each mass, by the square of its distance to any fixed point, is equal to the sum of the produets of each mass, by the square of its di- stance to the centre of gravity; plus, to the product of the total mass, by the square of the distance from the cen- tre of gravity to this fixed point: (this is a well-known pro- position in geometry, and easily proved ;) thus, in the case of attraction under examination, the sum of these two quan- tities should, in the case of equilibrium, bea maximum, i.e. its differential is equal to zero. Let us supposes for instance, that all the parts of the system are connected with each other, so as to form only one body, and that this body is suspended by its centre of gravity, so that this point is fixed; it is clear that each of the quantities mentioned will be con- stant; z.e. will remain the same, whatever situation we give to this’body, and the differential of their sum will con- sequently be null: thus there will be equilibrium; 7. e. if all the particles of a body are attracted towards a fixed point, proportional to their distances to this point, and if we sus- pend this body by its centre of gravity, it will remain in equilibrium precisely as in the case of ordinary gravity. It must not be concluded from this, however, that in a machine to which several bodies are applied, attracted towards a fixed point, in ratio of the distances, the position of equilibrium was that at which the centre of gravity of the system would be 126 On Machines in General. be at the lowest point, z. e. the nearest possible from the fixed point; for this only happens in the case in which all the parts of the system hold together and form but a single body : on the contrary, in the case of natural gravity, it ig not necessary, in order that the centre of gravity should be at the lowest point, that the paris of the system should be united with each other. tiie If bodies were attracted ‘towards the fixed point in he - inverse ratio of their distances to this- point, the principle alleged above would show that the /situation of equilibrium 1s then the situation at which the sum of the products of each mass, by the logarithm from its distance to the fixed point, is a maximum. | In general, if the bodies m of the system are attracted in ratio of a power 7, from their distances x, to this point, the situation of equilibrium will be that at which the quan- tity sma" +! will be a maximum, or greater than In any other situation ; 2. e. when the ditference of this quantity to what it would be, if the system was in a situation infinitely near, is equal to zero. : If there are in the system several fixed points, towards each of which the bodies m are attracted, in virtue of a power given from their distances to this point; so: that x, y,-%, &c. being the distances from m. to these different fixed points Ax", By?, Cxz4, &c. are the central forces of m towards these different foci, it will be the quantity B : n+ p+1 q+ + &c! which will be a maximum in the position of equili- brium. And if besides this, the bodies attract each other in ratio of any given power of the distances, in such a.way that X expressing the distance from the molecule m to each of the other molecules of the system, F X* is the motrix force attractive of m towards this other molecule, the situa- tion of equilibrium wilt be that where the quantity S08 9.54 5m or + tt Sm Yy ptt + —_ ——_— + SE Bere OA es Ee ee : “4! Cx: qtl On Machines in General. Lay C : us , Be - a ies &c. is a maximum 3 2. e. greater than in any other situation. \ It would be easy still to extend these consequences to other hypotheses of attraction; but this seems useless. TI shall therefore confine myself to remarking, that we may, by a principle ¢ ‘general to what we have shown, establish that Whatever be the nature of the motrix forces applied io a machine, if we make it move in such a manner that it passes by the position of equilibrium, the instant when it shall ar- rive in this situation, will be that at which the momentum of activity consumed during the movement, by these motrix forces, shall be greatest. That is to say, the momentum of activity which the pro- posed powers consume during the movement, goes on al- ways increasing until the Tee He has attained the position of cain] (ennai ; after which this momentum ¢oes on di- minishing in proportion as the system removes from this position when it has passed it; whatever, in other respects, may be the route which we make this machine assume in order to bring it to that situation. Suppose, for example, that each of the powers applied to a machine are of a given size, and that besides this we know one of the points of direction which it should have in order that there be equilibrium: I say that this situation of equili- brium is that at which the sum of the producis of each of these powers, given by the distance from the point of the _ machine where we suppose it applicd to the fixed point given upon its direction, 1s the least possible *: this is easily deduced from the preceding principle. All these things are so easily proved, after what has been said in the course of this second part, that it seems useless to dwell upon them. I shall therefore conclude this work — * It must be remarked, that in all we have said onthe subject of a ma- chine considered in diiereat positions, and of its passage from the one to the other; it must be remarked, 1 say, that these positions are always supposed to be such that we pass from the one to the other bya movement which is. at each instant of those I have called geometrical: otherwise ail these pros positions would be subject to the same defects with which Gn Vv. ) we have. theught fit to reproach the principle of Descartes, and of several others. 2 | With 198 - On Machines in General. with some reflections upon the fundamental laws from which I set out, in order to establish the theory which it contains. Rolections upon the fundamental Laws of Equilibr ium and of Movements. Atnong the philosophers who have been occupied with inquirtes respecting the laws of movement, some make mez - chanics an experimental science, others a science purely ra tional; 2. e. the former, comparing the phengmena of Na- ture, decompose them, as it were, in order to know what they possess in common with each other, and thus to re- duce them: to a smal] number of principal facts which serve to explain all the others, and to prognosticate what should happen in- every circumstance: the latter begin by hypo- theses, then, reasoning consequently to their suppositions, attain the discovery-of the laws which bodies would pursue in their-movements, if their hypotheses were conformable to Nature; then comparing their results with the phanomena, and finding that they agree, conclude that their own hypo- thesis is exact, 2. é. that bodies in fact follow the laws which they had at first only supposed. The first of these two classes of philosophers set out therefore in their researches from the primitive notions which Nature has impressed upon us, and from experiments which -she continually presents te us: the second class set out from definitions and hypotheses. With the former, the names -of bodies, of powers, of equilibrium, and of movement, answer-to first ideas; they cannot nor should not define them : the rest, on the contrary, having every thing to draw from their own sources, are obliged to define these terms -with precision, and to explain all their suppositions clearly: but if this method seems more elegant, it isalso much more difficult than the other; for there is nothing so perplexmg in most of the rational sciences, and particularly in the one’ ‘ under consideration, as to lay down at first precise-defi- _ Ritions, upon which no ambiguity remains: it would in- volve me in metaphysical discussions far above my ability, _40 investigate all those which have been hitherto proposed ;: I shall content myself with examining the: first and the-most simple. . : ; What On. Machines.in. General... 129 What is a body? It is, most) people: will tell us, an im- penetrable extent 5 2. e. which’ cannot be! reduced to a less space. But is this property net common to the body and to the empty space? Can a cubic foot of vacuum occupy a less space? It.is clear that: it;eannot. Suppose a cubic foot: of water, for example, is) contained in a vessel capable of containing two cubic feet and closed on all sides: suppose we shake or roll this vessel as much as we please, there will always remain a cubic foot of water and a cubic foot of va- cuum : here are two spaces, of different nature indeed, but both equally irreducible :—it.is not in this therefore that the characteristic property of bodies consists.. Other people. tell us that this property consists inmobility. The indefinite and empty space, say they, is immoveable, while bodies may be transported from one place of this space to another: but when the body A passes into B for example, Has not the empty space which was in B, passed into A? There isnot, in My opinion, more reason ‘for attributing the movement to the plenum which was im A, than to the vacuum which was in B; the movement consists in one of these spaces supplanting the other; and this supplanting being recipro- cal, the mobility is a property which belougs no more to one than to another. Without departing from our first supposition, When I shake the vessel half empty and half full, is not the-vacuum moved'as well as the fluids? I dip a hollow ball of metal intoa bottle; the ball goes to the bottom, Have we not here a vacuum which is moved in a -plenum, in the same way as bodies are moved in a vacuum? The full space does not therefore differ from the empty space, either in mobility or in irreducibility; the impenetrability — which distinguishes the first from the second, therefore, is not the same with this irreducibility ; it is something which we cannot define, because it is a primitive idea ! The two fundamental laws trom which I set out (X1.) are therefore truths purely experimental, and I have pro- posed them as such. A detailed explanation of these prin- ciples would not enter into the plan of this work, and per- haps would haye only darkened the subject: the sciences are Vol. 32. No. 126; Nov. 1808. pha like 130 =——sdDescription of improved Tram* Plates likeia-beautiful stream, the course of which mav ‘be’ easily followed when it has acquired a certain regularity, but if we’ wish to ascend to’ its source, we ‘shall find it in no parti- cular: spot, because it’ is’ diffused every’ where; it is spread im some measure over the whole surface of the earth : in the: samé way ifwe wish to ascend’ to the origin of the sciences, _ we find mothing but obscurity, vague ideas, and’ vitiated” circles 3and-we are lost in primary ideas. «°) —— SRE. pasleipthin improved Tram-Plates for Carriages “on Rail Roads. By aa CHARLES LE Caan, of Llanelly in ad Wa les *.- ‘ @.,4)'SEB, {! HAVE forwarded to-the Society of Arts, fe. a specimen of -my,new method of laying rails, or tram-plates, on sucha plan as has met the entire approbation of those who have seen it, and are acquainted with the principle on which such) roads should be formed. Rail roads are daily. increasing, from the great advantage they afford to those manufactories connected with mines and minerals, particularly to collieries. They also promote agriculture, by occasioning lime to be procured from places almost inaccessible by any other means, or from whence it could be otherwise brought on moderate terms. [ have also sent a drawing of my method of laying the! tram-plates, with an estimate of the saving that will arise to the public by adopting the said method, with necessary re- marks on the principle on which it is founded. The lead- ing rail or tram-plate has neither tenon nor mortise over the plug... The stop-plate terminates the specimen, which stop-. plate should go in with some degree of tightness when laid. for “actual use, but in the present case that force is not ne- cessary, as the weoden blocks, by a carriage of upwards of 209 miles, may in some small degree be misplaced. I hope. > * From Transacizons of the Society for the Encouragement of Arts, Manufac- tures, and Commeree, for 1807———Twenty guinéas were voted for this com muyitication. ’ any jor Carr ‘iages on Rail Reads: 131 any impediment of that nature will be rectified or allowed, "for. I wish it to be understood, that a stop-rail is intended , to be placed at every 30 yale, at which distance any re- pairs may be made within ten minutes, which. by the pre-, sent mode frequently occupies more than twice that time, exclusive of disturbing in some measure the line of road. By my method, the plates have a certain degree of plays. which is absolutely necessary to avoid that breakage which, too frequently takes place when they are fixed with nails and, plugs. The plates which I send ne bee fixed in stone blocks, and are nearly as rough as when taken from the sand. If I am fayoured with any mark of the Society’s approbation, . I. shall hold myself bound to transmit such further communi-. cations on this subject as may be required by them; or ie person desirous of adopting my plan. ig Iam, sir; your most obedient servant, | Cuarues Le Caan. Llanelly, Carmarthenshire, May 12, 1806. Te CT svior, VED sec. Reference to the Engraving of Mr. CuAries Le Caan’s apes Tram-Plates for Rail Roads. Plate IV. Fig. 5, 6,7, 8 The tram-plates, fig. 5 and 6, are fastened by means of a tenon and mortise AB, each having a correspondent bevel, | just sufficient to keep the end from rising up, so that the head of one plate confines the end of the other: by this means, the workmen are obliged to form their road in right lines, and maintain perfect levels, as the mortise and tenon confines them to the required exactness necessary to make a perfeet road : curves or any given segment may be formed with the same nicety, by having two bevel rails or plates made for such purposes. Fig. 6. A side view or longitudinal section of the two plates placed on their stone blocks or sleepers C D, show two. plugs in dotted lines, one bevel, the other perpendicular, cast in the_stop-rail or plate, which is so called as it pre- [2 yents 138 Description of improved Tram- Plates vetits‘the others from moving, and when' taken up releases all: those between the stop-plates ;* 25 yards of rail road made with these plates, may he taken up and replaced within ten miritites: The plugs in dotted lines are shown’ in their pro- per positions within the sleepers EF'G. ~The usual length of a tram-plate is three feet ; the flanch’ or outside edge H, about one inch and half ist 3 the sole or bed’ I, from threé inches and a half to four'inches broad, - aiid three-fourths of an inch thick; but these dimensions’ may be varied according to circumstances ; the most approved! weight has been 14 pounds to the foot, or 42 pounds to the plate; the ends from which the plugs project, and to which: the tenons atid mortises fasten, should be one-fourth of an: inch thicker than the other part of the plate. ‘Fig. 7. A B, Show the under part of the tenon and mortise, and the form of one of the sloping or bevel plugs. The diameter of the plug near the shoulder is one inch and three quarters, reducing to one inch, its length two mehes and a half, forming an angle of eight degrees, the plate from which it projects is counter-sunk, so thatthe shoulder of the plug may not receive any sharp pressure or prevent the plate from having a pe'fect bearing. There is a.small groove in the whole length of the exterior of each plug, to admit a wire to pass to ils extremity, to draw the plug out if broken’ by any accident, also to admit the ex- pansion of water, in case of severe frost. The blocks or sleepers, EF G, on which the tram-plates are placed, should by no means be less than 120 pounds each in weight, but should be heavier on some kinds of ground ;. the depth of the hole for the plug should be three inches, and worked according to the inclination of the plug, for which purpose the stone-mason should have a standard cast-iron’ gauge ; there should be projections, K, cast with the flanch or outside. edge of the tram-plate, as shown at: fig. 5, to make the plates lie firm om their sleepers. Fig. 8. Is asection of one of the ends of a tram-plate; in which H shows the flanch or upright edge, I the flat: part‘or'sole on' which the wheels of the waggouis run, D one se 3 for Carriages on Rail Roads. 133 of the plugs, K the projection behind the Boe to make the piate lie firm on the blocks. : Coverall Observations. The advantage of laying plates on the above inciple is obvious; the blocks being put in their places never sink he- low their intended level, the act of driving either nail 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 even with the plate, an€ are perpetually obstructing the passage of the waggon; the workmen frequently not proportioning their holes and plugs to the hole in the block, also occasious considerable break- age ; the exertion necessary to fix a rail or plate completely, is great; and numbers of plates, particularly when the iren is short or brittle, are broken near the mortises by :issing the stroke of the hammer, which must be used with great force. Advaniage gained é in laying my Tram- Plates in Compari ison with other Modes, ee i Se a Nails used in a mile, 3520 of 3 in tie parutls eat 4d. per |b. - - - - - OU PT) Nails lost or defective, computed at per mile 1 0 0 Plugs with their loss > - - - GO 955) By breakage of rails, average from experience 710 O Lessened by labour in block laying, caleulated at only two-pence per yard - Be ic.) OI a: By breakage of blocks - - - > 1 0 0 #.49 19 4 This calculation does not take in annual loss of nails, and breakage of blocks, which 1s considerable. ) ‘13 XXII. On toga cy ae XXIII. On the Inconver tibility of Bark into Alburnum. By- THoMAS ANpREW, Kyacut, Eisqi5,F.R.S. In a Letter to Sir Josuex BANks, Ta) PARSER tn 45 ‘MY DEAR SIR, ly a letter which J had the honour to address to you in the end of the last yeart, I endeavoured to prove that the mat- ter which composes the bark -of trees, previously exists in the cells both of their bark and alburnum, in a fluid state, and that this fluid, evén when extravasated, is capable of changing into a pulpous and cellular, and ultimately a vas- cular substance; the direction taken by the vessels being apparently dependent on the course which the descending fluid sap is made to take t.» The object of the present me- mioir is to prove, that the bark thus formed, always remains in the state of bark, and that no part of it is ever trans- muted into alburnum, as many very eminent naturalists have believed. Having procured, by grafting, several trees of a variety of the apple and crab tree, the woeds of which were distin- guishable from each other by their colours, I taok off, early in the spring, portions of bark of equal length, from branches of equal size, and I transposed these pieces of bark, in- closing a part of the stem of the apple tree with a covering of the bark of the crab tree, which extended quite round it, and applying the bark of the apple tree to the stem of the crab tree in the same manner. Bandages were then applied to keep the transposed bark and the alburnum i in contact with each other ; and the air was excluded by a plaster com- posed of, bees-wax and. turpentine, and with a covering of tempered clays * From Philosophical Transactions, 1808. + Philosophical ‘Transactions, 1807. a ; I hal observed this circumstance in many successive seasons; but i was not by any means prepared to believe. that such an arrangement could ‘take place in the coagulum afforded by an extravasated fluid; and Iam indebted to Mr. Carlisle for having pointed out to me many circumstances in the mo- tron and powers of the blood of animals, which induced me to give credit to the accuracy of my observations; and to that gentleman, and to Mr. Home, I have also subsequent! y to acknowledge many obligations. - . The Qn the Inconvertibility of Bark into Alturnum. 135 The interior surface of the bark of the crab tree presented numerous sinuosities, which correspended with similar ine- qualities on the surface of the alburmum, occasioned by the former existence of many lateral- branches. The interior surface of the bark of the apple tree, as well as the external surface of the alburnum, was, on the contrary, perfectly smooth and even. A vital union soon took place between the transposed pieces of bark, and the alburnum and bark of the trees to which they were applied; and in the autumn it appeared evident, that a layer of alburnum had been, in every iustance, formed beneath the transposed pieces of bark, which were then taken off. 3 Exainining the oreanization of the alburnum, which had been generated beneath the Wao pieces of bark of the’ crab tree, and which had formed a perfect union with the alburnum of the apple tree, I could not-discover any traces of the sinuosities I had noticed; nor was the uneven, surface’ of the alburnum of the crab tree more changed by the smooth transposed bark of the apple tree. The newly gene- rated alburnum, beneath the transposed bark, appeared per= fectly similar to that of other parts of the stock, and the di-’ rection of the fibres and vessels did not in any degree corre- spond with those of the transposed bark *. : Repeating this experiment, I scraped off the external sur- ace of the alburnum in several spaces, about three lines in diameter, and in these spaces no union took place between ~ ihe transposed bark and the alburnum.of the stock, nor was there any alburnum deposited in the abraded spaces; but.the newly generated cortical and albyrnous layers took a circu- lar, and rather elliptical, course round those spaces, and appeared to have been generated by a descegding fluid, which had divided into two currents when it came into contact + # Duhamel having taken off, and immediately replaced, similar pieces of the bark of young elms, subsequently found tbat the alburnum, which was generated beneath such pieces of bark, had not formed any union with the alburnum 6f the tree, beneath it. “But this great naturalist did not employ ligatures of sufficient power to bring the bark and alburnum into close con- tact, or the result woud have been different, 14 i with 136 On the Taeonvertibility of Bark into Alburnum. with the spaces from which the surface had been scraped off, and to have united again iminediately beneath them. . | Tn each of these experiments,.a new cortical and albur- . nous layer was evidently generated; and apparently by the ‘game means that similar substances were generated beneath . a plaster composed of bees-wax and turpentine, 1m former. experiments *; and the only obvious difference in the result appears to be, that the transposed and newly generated hark ‘formed a vital union with each other: and it is sufficiently evident, that 1f bark of any kind was converted into alburnum, it must have been that newly generated. For it can scarcely be supposed, that the bark of a crab tree was transmuted into the alburnum of an apple tree, or that the sinuosities of the bark of the crab tree could have been obliterated, had such transmutation taken place. There 1s not, however, any thing in the preceding cases calculated to prove that the newly generated bark was not converted into alburnum ; and the elaborate experiments of Duhamel sufficiently evince the difficulty of producing any decisive evidence in this case ; nevertheless I trust that [ shall be able to adduce such facts as, in the aggregate, will be found nearly conclusive. Examining almost every day, during the spring and sum- mer, the progressive formation of alburnum in the young shoots of an oak coppice, which had been fel‘ed two years preceding, I was wholly unable to discover any thing like the transmutation of bark into alburnum. ‘The commence- ment of the alburnous layers in the oak (qguercus robur) is distinguished by a circular row of very large tubes. These tubes are of course generated inthe spring; and during their formation, I found the substance through which they passed to be soft and apparently gelatinous, and much less tena- cious and consistent than the substance of the bark itself.; and therefore, if the matter which gave exisgence to the alburnum previously composed the bark, it must have been, during its change of character, nearly in a state of solution; but it is the transmutation of one organized substance into. the other, and not the identity only of the matter of both, * Philosophical Transactions for 1807, for On the Inconvertibility of Bark into Allurnum. 137 for which the disciples of Malpighi deatend’: and if the fibres and vessels of the bark really became those of the al- burnum, a very great degree of similarity ought to be found in the organization of hose substances. No such similarity, eae exists; and not any thing at all corresponding” with the circular row of large tubes in the alburnum of the oak is discoverable in the bark of that tree. These tubes are also generated within the interior surface of the bark, which is well defined; and during their formation the vessels of the hark are distinctly visible, as different organs ; and had the one been transmuted into the other, their progressive changes could not, I think, possibly have escaped my ob- gervation: nor does the organization of the bark in other instances, in any degree iachiente the character of the wood that is generated beneath it: the bark of the wych elm (ulmus montana) is extremely tough and fibrous ; and it is often taken from branches of six or eight years old, to be used instead of cords ; that of the ash (fraxinus excelsior) on the contrary, when taken from branches of the same age, breaks almost as readily in any one direction as in an- other, and scarcely presents a fibrous texture; yet the albur= num of these trees is not very dissimilar, and the one is often substituted for the other in the construction of agricul- tural instruments. Beith Ga Mirbel has endeavoared to account for the dissimilar or- ganization of the bark, and of the wood_into which he con= ceives it to be converted, by supposing that the cellular sub- stance of the bark is always springing from the alburnum, whilst the tree is growing, and that it carries with it part of seabiler veebet ace (tissu tubulaire) of the liber, or in- terior bark. These parts of the interior bark, which are thus removed from contact with the alburnum, he conceives fo constitute’ the external bark or cortex, whilst the interior part of the liber progressively changes into alhurnum. But if this theory (which I believe I have accurately stated, though I am not quite certain that I fully compre- hend its author *) were well founded, the texture ef the al- * Chap. iii, article 5, Traité @Anatgmic et de Physiologie Végetale, burnum 138 On the Inconvertilility of Bark into Allurnum, burnum must sufely be much more intricate and interwovert than it is, and its tubes would lie less accurately parallel with ‘each other than they do: and were the fibrous substance ‘of the bark progressively changing into alburnum, the bark must of necessity be firmly attached to the alburnum during ihe spring and summer by the continuity, and indeed iden- tity of the vessels and fibres of both thé substances. This, however. is not in-any degree the case, and the bark is in those seasons very easily separated from the alburnum; to which it appears to be attached by a substance that is appa- rently rather gelatinous than fibrous or vascular: and the ~ obvious fact, that the adhesion of the cortical vessels and fibres to each other is mnch more strong than the adhesion of the bark to the alburnum, affords another circumstance almost as inconsistent. with the theory of Malpighi, as with ~ that of Mirbel. : Many of the experiments of Duhamel are, however, ap- pirently favourable to the theory of Malpighi, respecting the conversion of bark ‘into alburnum ; and Mirbel has cited two, which he appears to think conclusive*. Jn the first _of these, Dubamel shows that pieces of silver wire, inserted in the bark of trees, were subsequently found in their albur= num; but Duhamel himself has shown,’ with his usual 2cuteriess and candour, that the evidence afforded by this ex- periment 1s extremely defective ; and he declares himself to be uncertain that the pieces of wire did not, at their firstin-_ sertion, pass between the bark and the albumum ; in which case they would necessarily have been covered by every suc- cessive Jayer of alburnum, without ni transmutation of bark into that substance fF. In the second experiment cited by Mirbcl, Duhamel has shown that when a bad of a peach tree, with a piece of bark attached to it, is inserted in a plum stock, a layer of wood perfectly similar to that of the peach tree will be found,’ in the succeeding winter, beneath the inserted bark. The state- ment of Duhamel is perfectly correct ; but the experiment ‘does not by any means prove the conversion of bark into wood ; for if it be difficult to conceive (as he yemiarks) that: * Chap. ii. article 5, Traité d’ Anatomie et de Physiologie Vig gclale. t pages ag Artres, liv. iv. ch. 3. ° ¢ an On the Inconvertibility of Bark into Alburnum, 139 an inserted piece of bark can deposit a layer of alburnum, it is at least as difficult to conceive how the same piece of bark can be converted into a layer of alburnum of more than twice its own thickness (and the thickness ef the alburnum depo- sited frequently exceeds that of the bark in this proportion), without any perceptible dimimution of its own proper sub- stance. The probable operation of the inserted bud, which js a well-organized plant, at the period when it becomes ca- pable of being transposed with success, appears also, in. this case, to Bare been over looked ; for I found that when I de- stroyed the buds in the sucegeding winter, and left the bark which belonged to them uninjured, this bark no longer pos- sessed any power to generate alburnum,. It nev Phan continued to live, though perfectly inactive, till it became covered by the successive alburnous layers of the stock; and it was found many years afterwards enclosed in the wood. It was, however, still bark, though dry and lifeless, and did not appear to have made any progress towards conyer- sion into wood. In the course of yery numerous experiments, which were made to ascertain the manner in which vessels are formed in the reproduced bark*, many circumstances came under ‘my observation which I could adduce in support of my opi- nion, that bark is never transmuted ‘into alburnum; but I do not think it necessary to trouble you with an account of them; for though much deference is certainly due to the opinions of those naturalists who have adopted the opposite theory, and to the doubts of Duhamel, I am not acquainted with a single experiment: which warrants the conclusions they have drawn; and I think that were bark really trans- muted into alburnum, its progressive changes could only have escaped the eyes of prejudiced or inattentive observers. In the course of the ensuing spring, I hope to address to you some observations respecting the manner in which the al- burnum is generated. Iam, my dear sir, your most obliged obedient servant, Elton, Dec: 29; 1807. ., Tuomas Anp. KNIGHT. * Philosophical Transactions for: 1807." ' XXIV. Analysis f iad ‘ani XXIV, Analysis of various Kinds of Pit-Coal. By Davip Musnet, Esq. To Mr. Tilloch. Alfreton Iron-Works, , Noy. 10, 1808. SIR, Tr has often been a matter of. surprise to'me that we should possess so scanty a share of knowledge on the component parts of pit-coal, or at least that so small a share of that knowledge should meet the public eye. Except the analysis given by Mr. Kirwan, I do not recollect any in our lan- guage. After this short preface, I shall offer no apology for sending you the details that follow. Welsh Furnace Coal from Cyfartha. The appearance of this coal is deep shining jetty black, possessed of an irregular crystallized fracture, rather in- clining to soft and friable. Specific gravity 1°337. 340 grains of this coal, in small pieces, were introduced into a close fitted iron retort. It continued longer in the fire withoutinflaming than the common sort of English or Scotch coals, and»afterwards burnt with a small quantity of light- coloured bituminous flame. Upon examining the result, I found. the pieces welded, though not run into one common mass; the exposed angles were: all rounded, but nu great degree of adhesion had taken: place. The coke thus obtained avas of a dark-gray silvery .colour, very sonorous, and weighed 31 -grams. Loss, 29 grains. ‘Voiatile matter,lost.inja heatynearly»white 8:5 Coke obtained - - - Q1'5 ne 100 parts. 100¢rains of this coke were reduced to'a fine powder, and exposed in‘an iron capsule heated to redness in contact with the external air. “After the complete combustion of the car- bonaceous ' matter, a grayish-red ash was found weighing “BITS grains : the coke is therefore composed of carbon 96°25, ashes 3°75, =100 parts.-. And-100 parts, of this coal will be ~ composed as follows ; VIKA Volatile | Analysis of vartous. Kinds of Pit~Coal. 144 Volatile matter. 8°500" peda gories Carbon. + 88068) alge Ashes os 3°432, 100. parts. Alfreton Furnace Coal. The appearance of this coal is glossy black, composed of alternate layers of soft coal and black, charry, carbonaceous matter, with now and then thin lamin of hard-coal. Cross fracture of the beds somewhat shining and pitchy. Specific gravity 1°235. Distilled under the same circumstances as the Welsh coal, the results were as follow : Small pieces of coal weighing 300 grains Coke obtained - - 1632 Loss 1362 Bituminous matter lost in distilling 45°5 Coke - Seda ge = oa "100" “parts. The fracture of this coke was more cellular than that of the Welsh, and the mass more united and compact; the colour a lighter gray. 100 parts of the coke was found _ composed of carbon 96°25,. ashes of a light-brown co- lour 3°75, = 100 parts. 100 parts of the same coal were composed of Bituminous matter and water 45°500 Carbon. - = - 52°456 Ashes - = - 2044 . 100 parts. Butterly Furnace Coal, Strong hard coal, colour dulllsooty black, fracture sharp and uneven. Specific gravity 1°64. 300 grains of it distilled, yielded 1714 grains of a: light- coloured gray silvery coke, The pieces were nearly of the 2 same m2 Analysis of varios Kinds of Pit-C€oai.. - same shape as when introduced; a few of the points and angles were rounded, but no welding from bituminous mat- ter had taken place. Volatile matter equal to 42°83 ‘Coke hard and dense ~- 56°17 100 parts. “100 grains of the coke by combustion were found to eontain, carbon 92-5, ashes of a pure white colour 7:5. And 100 parts of the same coal were ppt of Volatile matter 7 855 49"°830 Carbon - ~ 52°882 Ashes - - 4°288 100. parts Welsh Stone Coal. Specific gravity 1°368. Composed of water and hydrogen 8°0 Carbon - - 21Gb) Sara Ashes of a grayish-brown colour 2°3 100 parts. 100 grains of coke prepared from this coal lost 10 grains on being exposed for ten minutes in a heat of 178° of Wedgwood. The residuum was much more brilliant and metallic-looking than formerly. Welsh Slaty Stone Coal. Specific gravity 1°409. . Composed as follows ; Volatile matter - 97100 — Carbon - ~ 84°175 Ashes whitish-gray 6°725 100 parts. See This coal seems to correspond, in point of quality, ap- pearance and inflammability, with Cannel coal; or, in other words, it seems to bear the same relation so the stone coals as Cannel coal does to the bituminous coals. J haye there- . fore. ‘ / Analysis of various Kinds uf Pit-Coul. fore subjoined the analysis of a° Cannel ceal found in the same section of strata as the Alfreton furnace coal. 143 Derxlyshire Cannel Coal. Cemponent parts, ' Volaule matter = 47'O000 Carbon - < 48°362 Ashes reddish-brown colour 4°638 Specific gravity 1°278. 100. parts. Kilkenny Stone Coal: Specific gravity 1602. Component parts, Water and alittle hydrogen 4°950 - Carbon - - 92877 Ash of a clay-brown colour 2°873 100 ss parts. Stone. Coal found under Basalt, in Scotland. Water_and hydrogen - 16°660. Carbon - - - 69°74U Ashes = - 13-600 100. parts. Kilkenny Slaty or Cannel Coal. Specific gravity 1-445. Component parts, Matter volatilized in dark-gray fame 13°000 Carbon eval Matas - 80°475 ASHES: "a= - 86°560 Ashes - - - 3°140 100 parts. It is: worthy of remark, that the coke obtained from stone coals in general is of a greater specific gravity than the coal itself, and that itis very difficult, after the operation of coking ds performed, to distinguish between these two different states. | Stone Wood, fromthe Giants’ Causeway, Ireland. Specific gravity 1:150. Component parts, Lost in light-coloured flame resem- bling that of wood - ~ 33°370 Carbon - - - - 54°6907 Ashes ocbrey-brown colour - 11°933 100: parts, A piece of well-dried Oak was found composed of : Volatile matter = 80:0 Carbon = ss 19°5 Ashes deep brown - 5 ; 100 parts. 20 grains Analysis of various Kinds of Pit- Coal. 145 20 grains of each of the coals and cokes, contained in the followine Table, were fused with 100 grains of the same oxide of iron, and under similar circumstances. The results, as exhibited in the Table, will furnish ample subject for re- flection to those interested in iron, or in the affinities be- tween carbon and this metal. ; Volatile {20 Grains] Iron re- [Charcoal |20 Grains| Iron re- Charcoal Matter |raw Coal|vived forjleft in the; Coke re-|vived for|leftin the contained] revived each | Crucible| vived of} each Crucible in the | of Iron. | Grain of jnot acted) Iren. |Grain of {not acted Coal. é Coal, on. Charcoal. Grs. Grs. Grs. Grs. Grs. Welsh furnace coal 85. 40 2: 2: 34 1:725 . | Alfreton furnace ditto} 45:5 471 2°365 47 2:350 Butterly furnace ditto} 42-83 ae 2:20 42 2-100 Welsh stone coal - | 8° A31 2°16 1-75 39) 1-95 Welsh slaty ditto - | 9°100 461 2°325 3:50 371 1:875 Derbyshire Cannel i 5 coalia= - - | 47-000 49 2-100 461 9°325 Kilkenny coal - | 4:250 413 2-087 1:75 38 1-900 — Ditto slaty - ai Ss ae 2-075 2 5O 16 800 Boolavooneen coal |_ 13-800 441 2-925 3°50 18 -900 Corgee coal - - | 9°100 423 2:137 3° 27 1:350 Stone Coal, Queen’s County, No. 39 10-300 403 Z:O31/5s\ Do! 20 22995 Oak wood - - | 80-000 122 0 625 225 48 ~ 92:40 stone wood - - | 33°370 45 9:25 000 441 9°295 General Talle of the “Analyses of the foregoing Coal. upon. Grs. 2°75 ‘lr: 50 HOS) 2:75 4-25 3°50 ~ d Specific Specific. Volatile k i Gravity | Gravity iS | Matter. Carbon. | Ashes. of the of the Coal. Coke. Welsh furnace coal = 8-5 88:068 3-432 WS Sioa als Alfreton furnace coal - 45°5 52:456 2-044 1-235 | less than water Butterly tae coal é 42°830 | 52:882“] 4:288 1-264 1-100 Welsh stone coal - - 8: 89-700 2°300 | 1:368 1:3934 Welsh slaty ditto - - 9°100: | 84175 6°725 41 1409 Derby shire Cannel ditto - “| 47-000 | 48:362 | 4:638 1-278 Kilkenny coal - - 4:250 -} 92-877 2 873 1 602 1-6568 Stone coal found under basalt | 16660 | 69:740 | 15-600 Kilkenny. slaty coal = 13000 | 80475 6525 1°445 Scotch Cannel coal - -- 56 570 | 39-430 4/000 Boolavooneen ditto Queen’s County, No.39 Vol. 32 13:800 | 82:°960 | 3:240 1436 1:596 Corgee coal - tn 97100 | 87-491 3-409 1:408 1°6560 10:300 - f 867560 3°140 1403 16218 Stone wood, Giants’ Causeway | 33:370 | 54697 | 11-933 | 1150 Oak wood - = - 80 000 | 19°500 OUR ae ‘ = . D. Musuer. » No; 126, Nov. 1808: K. XXV. The f 146 j XXV. The Bakerian Lecture, on some new ‘Phenomena of Chemical Changes produced by Electricity, particularly the Decomposition of the fixed Alkalis, and the Exhibition of the new Substances which constitute their Bases; and on the general Nature of alkaline Bodies. By Humpury Davy, Esq., Sec. R.S. M.R.LA. Byencndes from p. 122.] VIII. On ihe Nature of py aa bs and alkaline Bodies # 17. general: with Observations on some Prospects of Discovery offered by the preceding Facts. Awemonia is a substance, the chemical composition of which has always been considered ‘of late years as most per- fectly ascertained, and the apparent conversion of it into hydrogen and nitrogen, in the experiments of Scheele, Priestley, and the more refined and accurate experiments of Bertholet, had }eft no doubt of its nature in the minds of the most enlightened chemists. All new facts must be accompanied however by a train of analogies, and often by suspicions with regard to the accu- racy of former conclusions. As the two fixed alkalis con- _ tain a small quantity of oxygen united to peculiar bases, may not the volatile alkali likewise contain it? was a query which soon occurred to me in the course of inquiry 5. and in perusing the accounts of the various experiments made on the subject, some of which I had carefully repeated, I saw no reason to consider the circumstance as impossible. For supposing hydrogen and nitrogen to exist in combination with oxygen in low proportion, this last prineiple might easily disappear in the analytical experiments of decompasi- tion by heat and electricity, in water deposited upon the ‘ vessels employed or dissolved in the gases produced. Ot the existence of oxygen in volatile alkali I soon satis- fied myself. When charcoal carefully burnt and freed from moisture wag ignited by the Voltaic hattery of the power of 250 of six and four inches square, in a small quantity of very On the Decomposition and Composition of the Alkalis. 147 very pure ammoniacal gas*; a great expansion of the aéri- form matter took place, and a white substance formed, which collected on the -sides of the glass tube employed in the process ; and this matter, exposed to the action of di- luted muriatic acid, effervesced, so that it was probably car- bonate of ammonia. A process of another kind offered still more decisive re- sults. In this the two mercurial gasometers of the invention of Mr. Pepys, described in No. XIV. of the Phil. Trans. for 1807 7, were used with the same apparatus as that em- ployed by Messrs. Allen and Pepys for the combustion of the diamond, and these gentlemen kindly assisted in the ex- periment. Very pure ammoniacal gas was passed over iron wire ig-- nited in a platina tube, and two curved elass tubes were so arranged as to be insested into a freezing mixture; and. through one of these tubes the gas entered into the platina tube, Fania through the other, it passed from the platina tube into ‘the airbolder arranged for its reception. _ The temperature of the atmosphere was 55°; but it was observed that no sensible quantity of water was deposited in the cooled glass tube transmitting the unaltered ammonia, but in that receiving it after its exposure to heat, moisture was very distinct, and the gas appeared in the airholder deusely clouded. This circumstance seems distinctly to prove the formas. tion of water in this operation for the decomposition of am- monia; unless indeed it be asserted that the hydrogen and nitrogen gases evolved, hold less water in solution or sus- pension than the ammonia decomposed ; an idea strongly * The apparatus in which this experiment was made is described in page 214, Journal of the Royal Institution. The gas was confined by mercury which had been previously boiled to expel any moisture that might adhere to it. The ammonia had been exposed to the action of dry pure potash, and a portion of it equal in volume to 10980 grains of mercury, when acted on by distilled water, left a residuum equal to nine grains of mercury only. So that the gas, there is every reason to believe, contained no foreign aériform matter; for even the minute residuum may be accounted for by ipbasne i it derived from air dissolved in the water. + Phil. Mag. vol. xxix. Ke opposed 148 On the Decomposition and Composition: opposed by the conclusions of Mr. Dalton*, and the expe- riments of Messrs. Desormes and Clement t. ‘ After the gas had been passed several times through the ignited tube from one gasometer to the other, the results were examined. The iron wire became converted superfi- cially into oxide, and had gained in weight -44, parts of a grain, about 4, of a grain of water were collected from the cooled glass tubes by means of filtrating paper, and 33°8 cubic inches of gas were expanded into 55°3 cubic inches, and by detonation with oxygen it was found that the hydro- \ gen gas in these was to the nitrogen as 3-2 to 1 in volume. | It will be useless to enter into the more minute details of this experiment, as no perfectly accurate data for propor- tions can be gained from them; for the whole of the am- Monia was not decomposed; and as the gas had been pre- pared by being sent from a heated mixture of sal ammoniac and quicklime, into the airbolder, it was possible that some solution of ammonia.might have been deposited, which, by giving out new gas during the operation, would increase the absolute quantity of the material acted upon. In examining the results of M. Berthollet’s ¢ elaborate ex- periments on the decomposition of ammonia by electricity, I was surprised to find that the weight of the hydrogen and nitrogen produced, rather exceeded than fell short of that of the ammonia considered as decomposed, which was evi- dently contradictory to the idea of its containing oxygen. This circumstance, as well as the want of coincidence be- tween the results and those of Priestley and Van Marum on the same subject, induced me to repeat the process of the electrization of ammonia, and I soon found that the quan-’ tities of the products in their relations to the apparent quan- tity of gas destroyed were influenced by many. different causes. Ammonia procured over dry mercury from a mixture of dry lime and mariate ofammonia, I found, deposited mois- ture upon the sides of the vessel in which it was coliected,: *® Manchester Memoirs, vol. v. part ii. page 535, 1785, + Annales de Chimie, vol. xhi. p.125. ‘{ Mémoires de 0 Académie, 1785, page 324, rh - and. of the fixed Alkaits. fh 149 and in passing the gas into the tube for electrization, it was not easy to avoid iesaisk some of this moisture, which must have been a a solution of ammonia, at the same time. In my first trials made upon gas, passed immediately from the vessel in which it had been collected into the apparatus, I found the expansion of one of ammonia vary in different instances from 2°8 to 2°2 measures ; ; but the proportions of the nitrogen and hydrogen appeared uniform, as determined by- ae onaion of the mixed gas with oxygen, and nearly as one to three in volume. To exclude free moisture entirely, I carefully prepared ammonia in a mercurial airholder, and, after it had been ‘some hours at rest, passed a quantity of it into the tube for decomposition, which had been filled with dry mercury. In this case 50 parts ‘became 103 parts by electrization, and there was still reason to suspect sources of error. I had used iron wires not. perfectly free from rust, for taking the spark, and a black film from the mercury ap- peared on the sides of the tube. It was probable that some ammonia had been absorbed by the metallic oxides both~ upon the iron and the mercury, which might again have been given out ir the progress of the operation. I now used recently distilled mercury, which did not leave the slightest film on the glass tube, and wires of pla- tina. The ammonia had been exposed to dry caustic potash, and proved to be equally pure with that mentioned in page 147. 60 measures of it, each equal to a grain of water, were electrized till no further expansion could be produced, the gas filled a space equal to that occupied by 108 grains of water. The thermometer in this experiment was at 067 and the barometer at 30°1 inches. The wire of platina trans- mitting the spark was slightly tarnished*. The 108 mea- sures of gas, carefully analvsed, were found to consist of 80 measures in yolume of hydrogen, and 28 measures of ni- trogen. : : _ * This most probably was owing to oxidation. Wien plare is made positive in the Voltaic circuit in contact with solution of ammonia, it is ra- pidly corroded, This isan analogous instance. . K 3 The / 150 On the Decomposition and Composition _ The results of an experiment that I made in 1799* give the weight: of 100 cubic inches of ammonia, as 18°18 grains at the mean temperature and pressure. I had reasons how- ever for suspecting that this estimation might be somewhat too low, and on mentioning the circumstance to Messrs. Allen and Pepys, they ently undertook the examination of the subject, and Mr. Allen soon furnished me with the fol- -Jowing data. ‘In the first experiment 21 cubic inches of ammonia weighed 4°05 grains; i a second experiment the same quantity weighed 4-06 grains, barometer 30°65, ther- mometer 54° Fahrenheit.” Now if the corrections for temperature and pressure. be made for these estimations, anda mean taken, 100 cubic inches of ammonia will weigh 18°67 grains, barometer being at 30, and thermometer at 60° Fahrenheit; and if the quantity used in the experiment of decomposition be calcu- Jated upon as cubic inches, 60 will weigh 11°2 grains. But . the hydrogen gas evolved cqual to 80 will weigh 193+ grains, and the nitrogen equal to pid 873. And 11°2 grains — 1°9 + 8'°3 = 10°2. and 11°2 — 10°29. = 1, all the estimations being made according to ind standard tempera- ture and pressure. So that, in this experiment on the decomposition of am- monia, the weight of the gases evolved is less by nearly ty than that of the ammonia employed ; and this loss can only be ascribed to the existence of oxygen in the alkali; part of which probably combined with the platina wires em- ployed for clectrization, and part with hydrogen, After these ideas the oxygen in ammonia cannot weil be estimated at less than seven or eight parts in the porte ; and it possibly exists in a larger proportion as the cases evolved may contain more water than the gas ‘econ * Researches Chem. and Phil. page 62, + Lavoisier’s Elements, p. 569. A cubicai inch of hydrogen is consider os as weighing ‘0239. + Researches Chem. and Phil. page 9. From my experiments 100 cubical - inches of nitrogen weigh at the standard temperature and pressure, 2¢*6 grains, which of the fixed Alkalis. 151 which ofcourse would increase their volume and their ab- solute weight *. In supposing ammonia a triple compound of nitrogen, hydrogen, and oxygen, it is no less easy to give a rational account of the phenomena of its preduction and decompo- sition, than in adopting the generally received hypothesis of ifs composition. - Oxygen, hydrogen, and nitrogen, are always present in eases in which volatile alkali is formed; and it usually ap- pears during the decomposition of bodies in whigh oxygen is loosely attached, as in that of the compounds of oxygen and nitrogen dissolved in water. At common temperatures under favourable circumstances, the three elements may be conceived capable of combining and of remaining in union: but at the heat of ignition the affinity of hydrogen for exygen prevails over the complex attraction, water is formed, and hydrogen and nitrogen are evolved ; and according to these conclusions, ammonia will bear the same relations to the fixed alkalis, as the vegetable acids with compound bases do to the mineral ones with simple bases. Oxygen then may be considered as existing in, and as forming, an element in all the true alkalis; and the prin- ciple of acidity of the French nomenclature might now likewise be called the principle of alkalescence. | From analogy alone it 1s reasonable to expect that the al- kaline earths are compounds of a similar nature to the fixed alkalis, peculiar highly combustible metallic. bases united to oxygen. I have tried some experiments upon barytes and strontites; and they go far towards proving that this must be the case. When harytes and strontites, moistened with water, were acted upon by the power of the battery of 250 of four and six, there was a vivid action and a brilliant light at both points of communication, and an inflammation at the negative point. * Inthe present state of our knowledge, perfectly correct data for pro- portions cannot probably be gained in any experiments on the decomposition of ammonia, as it seems impossible to ascertain the absolute quantity of water in this-gas; for electrization, according to Dr. Henry’s ingenious researches, offers the only means known of ascertaining the quantity of water in gases. K 4 In s 152 ~ On the Decomposition’ and Composition In these cases the water might possibly have in nterfered. Other experiments gave however more distinct results. Barytes and strontites, even when heated to intense white- ness, in the electrical circuit by a flame supported by oxygen gas, are non-conductors; but by means of combination with a very small quantity of boracic acid, they become conduc- . tors; and in this case inflammable matter, which burns with a deep red light in each instance, is produced from them at the negative surface. The high temperature has prevented the success of attempts to collect this substance; but there is much reason to believe that it is the basis of the alkaline earth employed. Barytes and strontites have the strongest relations to the fixed alkalis of any of the earthy bodies*; but there isa chain of resemblances, through lime, magnesia, glucina, alumina, and silex. And by the agencies of batterres suffi- ciently strong, and by the application of proper circum- stances, there is no small reason to hope, that even these refractory bodies will yield their elements to the methods of analysis by electrical attraction and repulsion. In the electrical circuit we have aregular series of powers, of decomposition from an intensity of action, ‘so feeble as scarcely to destroy the weakest affinity existing between the parts of a saline neutra] compound, to one sufficiently ener- getic to separate elements in the strongest degree of union, jn bodies undecomposable under other circumstances. When the powers are feeble, acids and alkalis, and acids and metallic oxides, merely separate from each other; when they are increased to a certain degree, the common metallic . oxides and the compound acids are decomposed; and, by means still more exalted, the alkalis yield their elements, * The sinularity between the properties of earths and metallic oxides was noticed in the early petiods of chemistry. The poisonous nature of barytes, and the great specific gravity of this substance as well as @f strontites, led Lavoisier to the conjecture that they were of a metallic nature. That metak existed i in the fixed alkalis seems however never to have been suspected. From their analogy to ammonia, nitrogen and hydrogen have been supposed to be amongst their elements. It is singular, with regard ¢o this class of bodies, that those most unlike metallic oxides are the first which have been demon, strated to be such, 7 - of the fixed Alkalis. - 153 And as far as our knowledge of the composition of bodies extends, all substances attracted by positive electricity are oxygen, or such as contain oxygen in excess; and all that are attracted by negative electricity are pure combustibles, or such as consist chiefly of combustible matter. The idea of muriatic acid, fluoric acid,- and boracic acid containing oxygen, is highly strengthened by these facts. And the g ae principle confirms the conjecture just stated concerning the nature of the earths. In the electrization of boracic acid moistened with water, I find that a dark-coloured combustible matter is evolved at the negative surface; but the researches upon the alkalis have prevented me from pursuing this. fact, which seems however to indicate a decomposition. Muriatic acid and fluoric acid in their gaseous states are non-conductors : and as there is every reason to believe that their bases have a stronger attraction for oxygen than water, there can be little hope of decomposing them in their aqueous solutions, even by the highest powers. In the electrization of some of their combinations there is however a probability of success. An immense variety of objects of research is presented in the powers and affinities of the new metals produced from the alkalis. In themselves they will undoubtedly prove ponedil agents for analysis ; and having an affinity for oxygen stronger than any other known substances, they may possibly supersede the application of electricity to some of the undecompound- ed bodies. The basis of potash I find oxidates in carbonic acid and decomposes it, atid produces charcoal when heated in con- tact with carbonate of lime. It likewise oxidates in muriatic acid; but I have had no opportunity of making the experi- ment with’ sufficient precision to ascertain the results. In sciences kindred to chemistry, the knowledge of the nature of the alkalis, and the analogies arising in conse- quence, will open many new views ; they may lead to the solution of many problems jn geology; and show that agents may 154 Successful Application of the Magnet, employed to may have operated in the formation of rocks and earths which have not hitherto been suspected to exist. . It would be easy to pursue the speculative part of this in- quiry to a great extent; but I shal] refrain from so occupy- ing the time of the Society, as the tenour of my object in this lecture has not been to state hypotheses, but to bring . -forward a new series of facts. XXVI. Successful Application of the Magnet, employed to extract a Fragment of Iron out of the [nee Eye, which had been lodged there about five Months. By Mr. Wiu- L1AM Preram, Sen., of Tenterden*. ¥ ‘Tenterden, July 12, a Asourt five months azo Charles Milsted, a blacksmith, of Tenterden, whilst in the act of striking tne head of one hammer against another, on a part of work which required him to strike with great violence, a particle of iron about the size of a small pin’s head, flew off from the head of the hammer, and darted into the ball of his left eye; the acci- dent was attended with extreme pain, and continued without any abatement. . Some weeks after this accident, I applied a magnet to the part injured, with an expectation that it might draw out the particle, hut I could only draw out a mixture of powdered rust with the tears. I supposed the salt liquid of the eye had dissolved this calx from the iron. This gave no relief, as the fragment of iron was yet remaining in the eye. A surgeon endeavoured to take it out with the point of a lancet; but the fragment was firmly fixed, and very near the pupil of the eve, so that it was impossible to touch it with any in- strument, but with extreme danger. Being informed the young man was in great agony, and without any hope of relief, I sent for him again this rath of July, with a desire to try once more what effect the magnet might have. I was * Communicated by Mr. John Swift, of Fenchurch-street.- | the 8 extract a Fragment of Iron out of the human Eye. 155 the more encouraged,. knowing the principle to be correct, and the power to be employed very great. I first examined the eye with a powerful magnifying glass, and I could dis- cover a very small particle of black iron, but covered over with the thin coating of the eye; the surface was even, and like the other parts of the eye. When I had satisfied myself of the exact situation, and of the impediments which I had to surmount, the eyelids were held open, and I applied the. north pole of a combined. staple magnet, possessing creat power, at the distance of about ~th of an inch from the eye; then I used another magnet of less power, but of more coavenient construction: thus I continued alternately to apply them both, and at last I could perceive the fragment of iron had projected above the surface of the iris of the eye. This.gave me some encouragement, although there was a coating to cut its way through, before the magnet could draw it out. To appearance it was as firmly fixed as a thorn in the flesh, and which prevented 1: from being drawn out so instantaneously, as the magnet, by its great attractive power, might have done, had the fragment been only loosely floating on the outer surface of the eye. During this operation the young man frequently thought. he felt the fragment rush out of his eye, before it actually was so. This sensation on so tender an organ was most likely produced by the great force with which the magnet attracted the fragment of iron; and as it was evidently dis- jodged from its former position, I was the more encouraged to be very earnest in my application. After using magnets of different degrees of power, and in various directions, for the space of about ten or fifteen minutes, the particle of iron cut its way through the thin teguments of the eye, by the power of attraction’, and was taken out by the magnet: I must confess that I was surprised to find so small a particle shonid have been the occasion of such long continued pains, but when the structure of that tender organ 1s duly consi= dered, the wonder will cease: by the assistance of glasses, the fragment appeared of an imperfect octagon shape, and armed with rough jagged edges. As soon as the fragment was drawn out, the eye was instantly free 156 Successful Application of the Magnet, &c. free from pain, although many months before, both ‘night and day, the pain had continued without intermission ; and the young man was unhappy from an apprehension that he must lose the sight of that eye, which had been much im— paired by the misfortune. A small scar remained on the eye, but it occasioned no pain. The weakest magnet which EF used for this operation will suspend a weight of about three pounds, and the strongest will suspend a weight of about Hfty pounds. The weakest magnet-by its construction, not being so unwieldy to manage as the other, gave me an op- portunity of approaching more closely to the organ of sight than I could with the largest; but I think thiey both had their use mn forcing the fragment to cut its way through the tezuments which enveloped it. Not being a medical man, it is probable I may not have given the deseription so accu- rately as it might have heen given ; but the effect produced, and the manner in which it was accomplished, I think can- not be misunderstood. ¥ must here recommend to persons who may be indaced to make use of the same means to dischar ge any particles of iron from the eye, not to be discouraged in their applica- tion, 1 the iron should not so suddenly be extracted as they mieht expect: they should take into consideration the de- gree of confinement, and every other existing obstacle be- tween the iron and the magnet; and should x not too hastily decline the operation. J have not stated these particulars as in imonelnes ex traordimary, nor as calculated to excite surprise. We all know that the natural property of the magnet is such, as to attract iron in every possible situation ; and we also know the pene- trating force of the magnetic. fluid will, with a degree of acne equal to the power communicated, make its pas- sage ever through plates of glass, when any particle of iron is within the cycuit of its influence. I can therefore only wonder that a means so familiar, and which seems to be pointed out by a law in Nature, should not more frequently be used on such occasions. - Wixiram PicraM Sen, XKVIL. Ror ee NS ES AT MOMVLD eomanks om the Incombustible Mon. To Mr. Tilloch. SIR, Waar nay be the accuracy of the experiments detailed in the last Number of your Magazine, by Dr. Sementini, re- lating to the imcombustible man, I know not; but of this Tam certain, that the Doctor has gone sadly out of his way to account for the method employed by Seior Lionetto, to render his tongue uninjured by the hot iron which he was. accustomed to pass over it. The fact is, that there is not the slightest occaston to de- fend the tongue with alum, sugar, soap, or any other sub- stance, for the purpose of rendering it insensible to the ac- tion of red-hot iron. f have repeatedly seen a friend of mine pass over his tongue, without any covering, a red-hot poker; and this experiment, which he has performed hun- dreds of times, to the great astonishment of dinner and tea. parties where he happened to be, I ventured (on his assurance that no hurt would ensue) to repeat. I found that it may be ° done with the utmost safety: the only effect is aslight taste in the mouth of carbonated hydrogen, and a very slight soreness for a short time.—Any of your readers may-satisfy themselves of the accuracy of this statement. It is only nepessaly that the tongue be wet with saliva before it is put out of the mouth, a that the poker be of course quickly passed over it. The cause of this phzenomenon I conceive to be, that the saliva is vaperized,-and in fact prevents the iron from ever actually touching the cuticle. Iam, sir, Your obedient servant, Hull, a 88S | November 8, 1808, } Iw addition to what has been stated above by W.S., I shall here mention a circumstance which occurred since the put - lication of Dr. Sementini’s paper. Having mentioned to a plumber, whom I had employed to repair a el cistern, some ef the particulars of the incombustible man, he expressed, Pe but 158 / Memoirs of Erasmus Darwin, M.D. but little surprise. Any one, he said, might draw their fin- ger through melted lead, if they did it somewhat quickly ; and having in his hand.a ladle full of melted solder, he in- | _Stantly passed his finger through it. He said he had often passed a red-hot piece of iron over his tongue, and seen others do it without injury. In the first experiment, he said, » it was necessary that the finger should be perfectly dry—if otherwise, the person might get what he called a zhimlle, i.e. some of the metal would stick to the finger and give a severe burn. In the experiment of passing a red-hot iron over the tongue, the iron, he said, should be very red—if only of a black beat, nearly-but not red-hot, it was sure to burn the tongue most severely.—The latter circumstance gives much countenance to the solution of the phenomenon offered by W.S. Itseems somewhat analogous to what takes place with a drop of water let fall on a plate of red-hot iron, which takes a much longer time to evaporate than a similar drop let fall on hot iron which would hardly shine in the dark. I shall here state another fact, which may, perhaps,, but hot quite so satisfactorily, be explained on similar principles. A gentleman informs me that he has seen au iron founder skim melted iron with his hand, The founder stated that he gould only do it when the iron was boiling hot :—if of a lower heat, it would burn him.—A. T. XXVIII. Memoirs of the late Erasmus Darwin, M.D. [Continued from p. 39.] DARWINIANA. Hyprocernanus internus, or dropsy of the ventricles of the brain, is fatal to many children, and some adults. When this disease is less in quantity, it probably produces a fever, termed a nervous fever, and which is sometimes called a worm fever, according to the opinion of Dr. Gilchrist, in the Scots Medical Essays. This fever is attended with great inirritability, as appears from the dilated pupils of the eyes, in which it corresponds with the dropsy of the brain. And the latter disease has its paroxysms of quick pulse, and in that a as — / Memoirs of Erasmus Darwin, M.D. 159 that respect corresponds with other fevers with inirrita- bility. The hydrocephalus internus is distinguished from apoplexy by its being attended with fever, and from nervous fever by the paroxysms being very irregular, with perfect intermis- sions many times in aday. In nervous fever the pain of the head generally affects the middle of the forehead ; in hy- drocephalus internus it is generally on one side of the head. One of the earliest criterions is the patient being uneasy on raising his head from the pillow, and wishing to lte down again ‘immediately ; which I suppose is owing to the pres- sure of the water on the larger trunks of the blood: -vessels en- . tering the eavity being more intolerable than on the smaller ones; for, if the larger trunks are compressed, it must in- convenience the branches also; but if some of the small branches are compressed only, the trunks are not so im-. mediately incommoded. | Blisters on the head, and mercurial ointment externally, with calomel internally, are principally recommended in this fatal disease. When the patient cannot bear to be raised up in bed without great uneasiness, it is a bad symptom. So I believe is deafness, which 1s commonly mistaken for — stupor. And when the dilatation of the pupil of either eye, or the squinting, is very apparent, or the pupils of both eyes much dilated, it is generally fatal. As by stimulating one branch of lymphatics into inverted motion, another branch is liable to absorb its fluid more hastily ; suppose strong errhines, as common tobacco snuff to children, or one grain of turbith mineral, (hydrargyrus vitriolatus,) mixed with ten or fifteen grains of sugar, was gradually blown up the nostrils? I have tried common snuff upon two children in this disease; one could not be made ta sneeze, and the other was too.near death to receive advan- tage. When the mercuriab preparations have produced sali- vation, I believe they may have been of service, but I doubt their good effect otherwise. In one child I tried the tincture of digitalis; but it was given with too timid a hand, and £00 ate in the disease, to fe ae its effects. As all the above remedies generally fail of success, bibadls frequent, Feo Wemhive of Erasmus Darn M.D. frequent, almost hourly, shocks of electricity from. very small charges might be passed through the head in all direc- tions with probability of good event; and the use of the. trephine, where the affected side can be distinguished. When one.eye is affected, does the disease exist in the ventricle. of that side ? Hydrops sroraciss Tae dropsy of the chest-commences with loss of flesh, cold extremities, pale countenance, high- eoloured urine in small quantity, and general debility, like many other dropsies. The patient next complains of numb- ness in the arms, especially when elevated, with pain and difficulty of swallowing, and an absolute impossibility of lying down for a few minutes, or with sudden starting from sleep, with great difficulty of breathing and palpitation by his heart. | ‘The numbness of the arms is probably owing more fre- quently to the increased action of the pectoral muscles in respiration, whence they are less at liberty to perform other offices, than to the connexion of nerves. The difficulty of - swallowing is owing to the compression of the cesophagus by the lymph in the chest ; and the impossibtlity of breath- ing in a horizontal posture originates from this, that if any parts of the lungs must be rendered useless, the inability ‘of the extremities of them must be less inconvenient to respi- ration; since, if the upper parts or larger trunks of the air-vessels should be rendered useless by the compression, of the accumulated lymph, the air could not gain admit- tance to the other parts, and the animal must'immediately perish. : If the pericardium is the principal seat of the disease, the pulse is quick and irregular. If only the cavity of the tho- rax is hydropic, the pulse is not quick nor irregular. If one side is more affected than the other, the patient leans most that way, and has more numbness in that arm. The hydrops thoracis is distinguished from the anasarca: - pulmonum, as the patient in the former cannot lie down ~ half a minute ; in the latter the difficulty of breathing, which occasions him to rise up, comes on more gradually; as the transition of the lymph in the cellular membranes from one = part Memoirs of Erasmus Darwin, M.D. 16y part to another of it is slower, than that of the effused isonet in the cavity of the chest. The hydrops thoracis is often complicated with fits of con- vulsive breathing; and then it. produces a disease’ for the time very similar to the common periodic asthma, which is perhaps owing to a temporary anasarca of the lungs; or to an impaired venous absorption in them. These: exacerba- tions of difficult breathing are attended with cold extremities, cold breath, cold tongue, upright posture with the mouth open, and a desire of cold air, and-a quick, weak, intermit- tent pulse, and contracted hands. These exacerbations recur sometimes every two or three hours, and are relieved by opium, a grain every hour for | two or three doses, with ether about a dram in cold waters and seem to be a convulsion of the muscles of respiration induced by the pain of the dyspnoea. ht ge M. M.A grain of dried, squill, and a asia ofa grain of blue vitriol every hour for six or eight hours, unless it vomit or purge. A grain of opium, Blisters. Calomel. three.grains every third day, with infusion of senna. Bark. Chalybeites Puncture in the side. Can the fluctuation in the chest be heard by saitaibiet tHe ear to the side, as Hippocrates asserts? Can it be felt by the hand or by the patient before the disease is too great to admit of cure by the paracentesis? Does this dropsy of the chest often come on after peripneumony?~ Isat ever cured by making the patient sick by tineture of digitalis? Could it be cured, if on one side only, by the operation of puncture between the ribs, and afterwards by inflaming ‘the cavity by the admission of air for a time, like the cure of ‘the hydro- cele; the pleura afterwards adhering wholly to that lobe of the lungs, so as to prevent any future effusion of mucus? Olesitas.—Corpuleney may be called an anasarca or dropsy of fat, since it must be owing to an analogous cause; that is, to the deficient absorption of fat compared to the ew tity secreted into the cells which contain it. The method of getting free from too much fat ‘withdut any injury to the constitution, consists, first, in putting on a proper bandage on the belly, so that it can be tightened Vol. 32, No. 126. Nov. 1808. L or ¥62 Memoirs of Erasmus Darwin, M.D. ot-relaxed with ease, as a tightish under waistcoat, with @ double row of buttons. This is to-compress the bowels and increase their absorption, and it thus removes one principal cause. of corpulency, which isthe looseness of the skin. Secondly, he:should omit one entite meal, as supper; by this long abstinence from food the absorbent system will act on ‘the mucus and. fat with greater energy. Thirdly, he should drink as little as he cam with ease to his sensations ; since, if the absorbents of the stomach and bowels bupnly the blood with much, or perhaps too much, aqueous fluid, the absorbents of the cellular membrane will act with less energy. Fourthly, he should use much salt or salted meat, which will increase the perspiration and make him thirsty ; and if he bears this thirst, the absorption of his fat will be greatly increased, as appears in fevers and dropsies with thirst; this I believe to be more efficacious than soap. Fifthly, he may use aérated alkaline water for his drink, which may. be supposed to render the fat more fluid,or he may take soap wm large quantities, whitch will be decomposed in. the stoniachs ‘Sixthly, short rest, and constant exercise. ' Bronchocele.—Swelled throat. An enlargement of ‘the thyroid glands, said to be frequent in mountainous countries, where river, water is drunk which has its source fromy dis> solying snows. This idea is a very ancient one, but perhaps not on that account to be the more depended upon, as au- thors copy‘one another. *Tumidum guttur quis ‘miratur in alpibus?’ seems to bave been a’proverb in the time of Juvenal. The inferior people of Derby are much subject -to this dis- ease, but whether more so than other populous towns, I cannot determine; certain it is, that they chiefly drink the | water of the Derwent, which arises in a mountainous coun- try, and is very frequently blackened as it passes through -the morasses near its source; and is generally-of a darker colour, and attended with a whiter foam, than the Trent, into which it falls: the greater quantity and whiteness of its froth, I suppose, may be owing to the viscidity communi- -eated to it by the colourmg matter. The lower parts of the town of Derby might be easily supplied with spring water from St. Alkmond’s well; or the whole of it from the - ° abundans Memoirs of Erasmus Darwin, M.D: 163 abundant Springs near Bowbridge; the water from which might be conveyed to the town in hollow bricks, or clay- pipes, at no very great expense, and might be received into frequent reservoirs with pumps to them ; or laid amie the houses; M.M. Twenty grains of burnt sponge with ten of nitre made with mucilage into lozenges, and permitted to dissolve slowly under the tongue twice a day, is asserted to cure ina few months; perhaps other animal charcoal, as candle- snuffs, might do the same. I have directed in the early state of this disease 4 mixture of common salt and water to be held in the mouth, parti- cularly under the tongue, for a few minutes, four or six times a day for many weeks, which has sometimes suc- ceeded: the salt and water is then spit out again, or in part _ swallowed. Externally vinegar of squills has been applied, or a mercurial plaster, or fomentations of acetated ammo- niac, or ether. Some empirics have applied caustics on the 4 bronchocele; and sometimes, I have been told, with suc-_ cess; which should certainly be used where thereis danger of suffocation from the bulk of it. One case I saw, and one I was well informed of, where the bronchocele was cured by burnt sponge, and a hectic fever supervened with colliquative sweats; but Ido not know the final event of either of them. — De Haen affirms the cure of bronchocele to be siieeeed by flowers of zinc, calcined egg-shells, and scarlet cloth burnt together in a close crucible; which was tried with success, as “he-assured me, by a late lamented physician, se friend, Dr. Small of Birmingham. Scrophula.—King’s evil is known by tumours of the lym- phatic glands, particularly of the neck. The upper lip, and division of the nostrils, is swelled, with a florid countenance, a sinooth skin, and a tumid abdomen. Cullen.—The absorbed fluids in their course to the veins in the scrophula are ar- rested in the lymphatic or conglobate glands ; which swell; and after a great length of time inflame and suppurate. Materials of a peculiar kind, as the variolous and venereal matter, when absorbed in a wound, paris this torpor; 1, and # 64 Memoirs of Erasmus Darwin, M.D. and consequent inflammation of those lymphatic glands where ‘they first arrive, asin the axilla and groin. There is reasom to suspect, that the tonsils frequently become inflamed, and _ suppurate from the matter:absorbed from carious teeth; and J saw a young lady, who had hoth the axillary glands Sol ed, and which suppurated ; .which was believed to have. been caused by her wearing a pair of new green gloves for one day, when she had perspired much, and was much ex- hausted and fatigued by walking: the gloves were eh dyed in a solution of verditer. . These indolent tumours of the lymphatic sagas wile constitute the scrophula, originate from the inirritability of those glands; which therefore sooner fall into torpor after having been stimulated too violently by» some poisonous material; as the muscles of enfeebled people sooner become fatigued, and ccase to act, when exerted, than those of stronger ones. On the same account these scrophulous glands are much longer in acquiring increase of motion, after having been stimulated into inactivity, and either re- main years in a state of indolence, or suppurate with diffi- culty, and sometimes only partially. The difference between scrophulous tumours, and: those before described, consists m_this ; that in those either glands _of different kinds were diseased, or the mouths only. of .the lymphatic glands were become torpid ; whereas in scrophula the conglobate glands themselves become tumid,- and gene- rally suppurate after a great length of time; when yor ac- quire new sensibility. These indolent. tumours may be tehowalit to suinpttnalge sometimes by passing electric shocks through them every: day for two or three weeks, as I have witnessed. It is pro- bable, that the alicruate application of snow or iced water to them, till they become painfully cold, and then of warm flannel or warm water, frequently repeated, might restore their irritability. by accumulation..of sensorial power; and thence either facilitate their dispersion, or occasion them to suppurate. This disease is very frequent amongst the children of the poor in large towns, who are in general ill fed, ill lodged, and Memoirs of Erasmus Darwin, M.D. 165 ‘and ill clothed; and who are further weakened by eating much salt with their scanty meal of insipid vegetable food, ,which is seldom of better quality than water gruel, with a little coarse bread in it. Scrophulous ulcers are difficult to: heal; which is owing to the deficiency of absorption on their. pale and flabby surfaces, and to the general duncan of: the system. M.M. Plentiful diet of flesh-meat and cenetables with small-beer. Opium, from a quarter of a grain to half a grain twice a day. Garudatia, Tincture of digitalis, thirty drops twice aday. Externally sea-bathing, or bathing in salt and water, one pound to three gallons, made warm. The ap= plication of Peruvian bark in fine powder, seven parts, and white lead (cerussa) in fine powder one part, mixed to- gether and applied on the ulcers in dry. powder, by means of lint and a bandage; to be renewed every day. Or very fine powder of calamy alone, lapis calaminaris. If powder of manganese ? be Scirrhus eesophagi.—A scirrhus of the throat contracts the passage so as to render the swallowing of -solids impracti- cable, and of liquids difficult. It affects patients of all ages, but is probably most frequently produced by swallowing bard angular substances when people have lost their teeth ; by which this membrane is over distended, or torn, or-other- wise injured. M.M. Put milk into a bladder: tied toa coal or cathe- ter; introduce it past the stricture, and press it into the © stomach. Distend the stricture gradually by a sponge-tent fastened to the end of whalebone, or by a plug of wax, or a spermaceti candle, about two inches long; which might — be introduced, and left there’ with a string only fixed to it - to hang out of the mouth; to keep it in its place, and to re- tract it by occasionally ; for which purpose the string must be put through a catheter or hollow. probang, when it is.to be retracted. Or lastly, introduce:a gut fixed to a pipe; and. then distend it by blowing wind into it. -The swallowing a bullet with a string put through it, to retract it on the exhi- bition of an emetic, has alsa been proposed. Externally mercurial ointment bas been much recommended, Poultice. jes ee Oiled \ 166 ‘Memoirs of Erasmus Darwin, M.D. Oiled silk. Clysters of broth. Warm bath of broth. Trang-*’ fusion of blood into a vein three or four ounces a day? I directed a young woman about twenty-two years of age,’ to be fed with new milk put into a bladder, which was tied to a catheter, and introduced beyond the stricture in her throat ; after a few days her spirits sunk, and she refused to use it further, and died. Above thirty years ago I proposed to an old gentleman, whose throat was entirely impervious, tq supply him with a few ounces of blood daily from an ass, or from the human animal, who is still more patient and tractable, in the following manner: To fix a silver pipe about an inch long to each extremity of a chicken’s gut, the part between the two silver ends to be measured by filling it with warm water ; to put one end into the vein of a person hired for that purpose, so as to receive the blood returning from the extremity 5 and when the gut was quite full, atid the blood running through the other silver end, to inttoduce that end into inte vein of the patient upwards towards the heart, so as to admit no air along with the blood. And jaaely, to support the gut and silver ends on a water plate, filled with water of ninety-eight degrees of heat, and to measure how many ounces of blood was introduced by pass~ ing the finger, so as to compress the gut, from the recciving pipe to the delivering pipe ; ; and thence to determine how many gut-fulls were given from the healthy person to the patient. Mr. —— considered a day on this proposal, and then another day, and at length answered, that ‘he now found himself near the house of death ; and that if he could return, he was now too old to have much enjoy-nent of life; and therefore he wished rather to proceed to the end of that journey, which he was now so near, and which he must at ‘all events soon go, than return for so short a time.” He lived but a few days afterwards, and seemed quite careless -and easy about the matter. [To be continued.] - XXIX. 4 [ler 4 wh ef XXIX. A Letter on the Differences in the Rreare of Calculi, which arise from their being formed in different Parts of the urinary Passages ; “fis on the Effects ihat are produced upon them, by ihe internal Use of solvent Medicines, from Mr. Witt1aAM BRANDE to EveRarD Home, Esq.; F.R.S.* DEAR SIR, Havine availed myself of the opportunity you procured for me, of making.a chemical examination of the calculi contained in the Hunteriaa Museum, as well as those in your own collection, I herewith. send you an account ef 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- commonly large, but the greater part of the specimens haye histories of the case annexed to them. This circumstance enabled me not only to ascertain “the 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 mere clear and perspicuous, Secrion I. Of Calculi farmed in the Kidneys, and voided without having afterwards undergone any Change in the urinary Passages. 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 emitan odour of ammonia. When heated to dryness, with nitric acid, the residuum is of a fine and permanent red colour. | When exposed to the action of the blow-pipe, they * From Philosophical Transactions for 1808. L4 blacken 168 On the Differences in the Structure of Calculi. * -blacken and emit a strong 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 calcull. Its relative quantity is hable 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 mu- riatic acid (rather more than sufficient for the saturation of the potash) was added, and the precipitate of uric acid thus obtained weighed when dry 4°5 grains. No other substance, except animal matter, which was evident on attempting to obtain the muriate of potash, could be detected, consequent~ ly the composition of this calculus was as follows: ; y Grs. Uric acid - A4°5 Animal matter 25 7'0 ‘ This is the largest proportion of animal matter which } have met with. A small calculus from the kidney, weighing 3°7 grains, afforded by a like treatment 3°5 grains of uric acid, so that 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- ther so as to form a calculus, but are voided in the state of a fine powder, commonly termed sand. This consists either of uric acid, or of the ammoniaco-magnesian phosphate, alone, or with the phosphate of lime. - -I am induced to believe that the last-mentioned substances, eanch the production of the kidneys, and held in salution, are never met with in a separate state tll the urine has been * Comment. on the Hist. and Cure of Diseases, 3d edit. p. 88, at F On the Differences in the Structure of Calculi. - 169 at rest, and therefore : and of a gray colour, and not very hard. SECTION II. “Of Calculi which have been retained in the Kidney Yf« When one or more of the calculi described in the pre- ceding section are detained in the infundibula or pelvis of the kidney, it frequently happens that they increase in that si-~ tuation to a considerable size. : This increase 13 of two kinds. 1. 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. . 2. Where there is less disposition to form uric acid, “ge external lamine are composed of the ammoniaco-magnesian phosphate, and phosphate of lime, In one instance, a small uric calculus had been deposited in the kidney, in such a situation that its upper surface was exposed to a continual stream of urine, upon which beau- tiful crystals of the triple phosphate had been deposited, ft 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, SecTion III. r Of Calculi of the urinary Bladder. Calculi met with in the bladder are of four kinds. 1. Those formed upon nuclei of uric acid, from the kidney. 2. Thase formed upon nuclei of oxalate of lime, from the kidney. 3. Those formed upon sand or ae mucus, Geposited in the sguitanes 4, Thais 4 170 On. the Differences in the Structure of Caicutt. 4. Those formed upon extraneous bodies introduced inte the bladder. They were arranged under the following divisions. 1. Calculi, which from their external appearance consist chiefly of uric acid. These calculi vary in colour from a deep reddish brown, — to a pale yellowish brown. They are either entirely soluble ia a solution of pure pot- ash, or nearly so. During their solution they frequently emit the odour of ammonia. When acetic acid is added to their alkaline solution, a pre- cipitate possessing the properties of uric acid is obtained. 2. Calculi, composed chiefly of the ammoniaco-magnesian phosphate, or of phosphate of lime, or of mixtures of the two. These calculi are externally of a whiter appearance than the former. ith Some perfectly white, others gray, eccasionally exhibiting small prismatic crystals upon their surface; others again soft and friable, a good deal resembling chalk. They are further characterized by their solubility im dilute muriatic acid. 3. Caleuli, containing oxalate of lime ; commonly called mulberry calculi. These are distinguished by the difficulty with which ety dissolve in dilute acids, by their hardness, and by leaving pure lime, when exposed to the action of the blowpipe. Jn the examination of these calculi, I was struck with the small number of those strictly belonging to the first division, having been led, from the account of Fourcroy and Vau- quelin*, and the experiments of Dr. Pearson, to believe that calculi composed of pure uric acid were by no means unfrequent. The greater number of the calculi examined by the former chemists, are stated to be completely soluble in the fixed al- _ kaline leys; and of three hundred examined by Dy. Pearson, a large proportion 1s said to consist of uri¢ acid, _* Annales de Chimie, xxxii. p. 218, . + Philosophical Transactions for M7985, 2» Sbeilins S vy. . The On the Differences in the Structure of Calculi. ¥74 ~ The following is a statement of the composition of the dif- ferent calculi ae in the bladder which I have examined. 16 were composed of uric acid. 45 uric acid with a small relative pro- portion of the phosphates. 66 ———_—_————- the phosphates, with a relatively small proportion of uric acid. 12 ——_—__.——. 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 care-_ Fully cut through with a fine saw, and a portion of the whole cut surface removed by a file; in this way all the different ingredients of the calculi were obtained. In the experiments upon uric calcul: from the bladder, f£ found in most instances, a far more considerable loss. in attempting to obtain their pure uric acid, than in the kidney calcuii ; which led me to suppose that they contained urea, 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- fition 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 pf 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 separated. The inso- luble part of the calculus, being now carefully dried and weighed, was found to have lost 5:5 grains. ~ * Fourcroy observes that urate of ammonia is easily detected by its rapid solubility in the fixed alkalis, and the odour of ammonia, which is perceived during t its solution Vide Thomson’s Syst, of Chem. vol. v. p. 691. The 172 On the Differences in the Structure of Calcult. | 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- lake cal 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 de- canted 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 alcohol. On evaporating the alcoholic solutions, a substance was obtained having all the properties of urea, with a small por-. tion of saline matter, probably muriate of ammonia, as by the addition of potash a slight ammoniacal odour was per- ceptible ; its quantity howeyer was too minute for accurate examination. The remaining portion of the calculus, weighing 54:8 grains, was treated with small portions of acetic acid, by which six grains of the ammoniaco-magnesian phosphate were obtained. The part of the calculus remaining after this treatment, weighing 48°8 grains, was perfectly soluble in a splution of. 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 compasitien ae this calculus. ~ Grains. Urea, and muriate of ammonia 2572 Ammoniaco-magnesian phosphate 6° Uric acid ~ - 48°8 60° From these and many similar experiménts upon other cal- culi, hitherto generally supposed to consist of urate of am- monia, I am induced to believe that the evolution Of am- - jmonia On the Differences in the Structure of Calcul. 17% mionia depends in all instances upen the decomposition-of the ammoniacat salts contained in the calculus, more especially of the ammoniaco-magnesian phosphate, and that no sub- stance which can be called urate of ammonia exists in calculi. The mulberry calculus (oxalate of lime) I have but rarely met with. In those preserved in the Hunterian coilection, there is a large relative proportion of phosphate of lime, and of uric acid. The purest of them afforded Grains. Oxalate of lime - 65° Uric acid - => 16: ’ Phosphate of hme - BSP Loss in animal matter 4° 100° When calculi of the urinary bladder increase to a very large, size, they are generally composed ef two or even three of the abovementioned varieties, the ammoniaco-magnesian phos- phate being situated externally, andin the greatest abundance. The largest calculus which I have seen, weighed, when recently removed from the bladder, twenty-three ounces and twenty-six grains. It consisted of a large mulberry or oxa- Tate of lime calculus, the nucleus of which was uric ‘acid, surrounded by a considerable quantity of the ammoniaco- magnesian phosphate in a very pure state. MeHother very large calculns, weighing fifteen ounces and a half, consisted te a nucleus of urie acid, enveloped in the ammoniacosmagnesian phosphate, not however pure, but intersected by several lamina of uric acid. Four distinct substances are extremely rare in calculi; I have seen one in which the uric acid, the ammoniaco-mag- 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 for their nuclei, were examined. ED 1. A common garden pea. 2. A needle. 3. A hazel nut. 4. A part of a common hougie. In the two first instances, bey calculous depositions were of 474 On the Differences in the Structure of Calculi. ‘of a pale gray colour, inclining to white; soft and friable i their texture, and entirely soluble in muriatic acid. The composition of the first was as follows : Grains. Phosphate of lime oe 65° Ammoniaco-magnesian phosphate — 28° Loss < - e. 7 100° Of the abana Phosphate of line = - 45% Ammoniaco-magnesian phosphate 38° Oxalate of lime fa kos We CC Loss s 2 2 5° 100°* The deposition of calculous miatter upon the bougie was covered with blood, and in very small quantity, the bougie having been removed by an operation soon after it had passed into the bladder. It appeared to consist chiefly of phosphate of lime. Y The incrustation upon the hazel nut was also destitute of uric acid. Section IV, Of Calculi of the Urethra. All those that were examined had escaped from the bladdef while very small, and had afterwards lodged in the membra- nous part of the urethra, where they had increased in size, and formed a cavity in which they were more orless embedded, Two of these calculi were broken. soft The fragments consisted, in one instance, of ammoniaco= ° magnesian phosphate, and phosphate of lime, with a smalf< portion of uric acid: and in the other the fragments were composed entirely of the ammontaco-magnesiau phosphate. The third calculus was of a very remarkable appearance 5 its form being that of a perfect sphere, about half an inch in diameter. It was coated with smal] but very-regular-crystals of the triple phosphate in its purest state.’ On account of the ‘* Jt appears that in this case there had been an accidental disposition al | the formation of oxalate of lime. i had. Slt ™ singularity On the Differences in the Structure of Calcult, 175 singularity of the form and external appearance of this cal- culus, it was not sawn through; the nucleus, in all proba- bility, is a small kidney calculus, which lodging in the ure- thra has become coated with triple phosphate. Section V. . Analysis of Calculi from other Animals. t. THE Horse. A. From the kidney. A very large calculus, from the kidney of 2 horse, was composed of > | Phosphate of lime — - 76° Carbonate of lime - 23° 98° B. From the bladder. This calculus was also of a large size, its weight when per- fectly dry nine ounces and a half, its external surface very irregular, of a reddish brown colour, and covered with minute erystals of the ammoniaco-magnesian phosphate. On making a section of it, the internal structure exhibited a radiated ap- pearance, and was of a light brown colour. It consisted of Phosphate of lime - - 45° Ammoniaco-magnesian phosphate 28° Animal matter © - - - 15° €arbonate of lime - - 10° 98° In another case the bladder of a horse was found to be nearly full of sand, the composition of which was as follows: “a Phosphate of lime —- 60° Carbonate of lime ~< 40> i) 4. #00: ¥, THe Ox. A number of small calculi from the size of a pea down- wards, ate not unfrequently found in the bladder of the ox. Those in the Hunterian collection are of a pale brown co= four, and of the size just mentioned ; some of them have the mulberry appearance. They ~ 376 Onthe Differences i in the Structure of Calculi. They consist of carbonate of lime and animal matters- which last substance retains the form of the calculus, . after, it-has been acted upon by diluted acids. 3. THE SHEEP: A calculus from the kidney: of a Heep was composed of Phosphate of ime — = Hoe Carbonate of lime = © &@s Animal matter - st é 1C0° iy 4, Tue RuINOCEROS. . The urine of this animal is exceedingly turbid at the time it is voided, and, when allowed to remain at rests deposits a very large proportion of sediment, which consists of car- bonate aa lime, with small portions of phosphate of lime and animal matter. 5. THE Doe. A large calculus from the bladder of a dog twenty years old, weighing sixteen ounces, was extremely hard, and of a gray cola. ; 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 ammoniaco-magnesian phosphate. The part of the stone surrounding the nucleus consisted of Phosphate of lime - 64 Ammoniaco-magnesian phosphate 30. Animal matter = 2 G. 100. Safid taken from a dog’s bladder was of a gray coloury- + and contained Carbonate of lime - °° 20° Phosphate of lime — - 80° we | 100". 6. Tur Hoc. 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. “ets - as ‘lts . “ — Tables of all the Frigorific Mixtures, &o. 197 Its internal structure was uniform, and there was no ap- pearance of a nucleus. It was composed of ; Carbonate of lime - 0° Animal matter - 10° ~ 100° 7. THE Rappirt, A calculus from the rabbit’s bladder weighing four drachms, was of a dark eray colour, and appeared as 1f composed of several smaller calculi. It consisted of Phosphate of lime - _ 39° Carbonate of ime ~-- 42 Animal matter = 19°. 108° [To be continued. ] 4 XXX. Tables exhibiting a cole ctive View of all the- Fri- gorific Mixtures coniained in Mr. Warker’s Publica- B isine 1808. To Mr. Tilloch. SIR, Is witt be found, on comparing ‘the tables in the various publications that have noticed the subjéct of artificial cold, (Cavatlo’s Experimental Philosophy ‘excepted,) witli the fol- lowing tables ;,or with the tables in the Philosophical Trans- actions, where these experiments originally appeared, that se- veral errors, respecting the effects of the frigorific mixtures, _ have happened. An error of this kind in one instance, viz. in the ninth mixture, of the first table, is no less than forty- two degrees ; the result in that iastance being —21°, whereas in the aces tables it is rendered 21°. This error seems to have arisen from the person who co- pied the tables from the Philosopbical Transactions, or my publication, originally, having overlooked the minus cha- racters expressed in Table I. altogether. Various other errors, likewise, will, on examination, be detected, particularly in the first_four mixtures of Table II. _ Desirous that these errors should be corrected in future publications, I have taken the liberty of addressing this to'you, witha genuine copy. I amy; sir, your obedient servant, Queen-Street, Oxford, ~ - Ro. WALKER: - Nov. 13, 1808. rf Vol. 32. No. 126. Nov. 1808. M Table t 178 Collective View of all the Frigorific Mixtures "* i Table Tl. aay This Table consists of frigorific mixtures, having the power of generating or creating cold, without the aid of ices sufficient for all useful and philosophical purposes, in any part of the world, at any season. + Frigorific Mixtures, without Ice. Degrees of cold, Mixtures. Thermometer sinks. ¢ produced, Muriate of ammonia . 5 parts Nitrate of potash .... 5 From + 50°%to+ 10% 40 WALEE obras hinge ciate 16 Muriate of ars . § parts Nitrate of potash .... 5 ¢ . Sulphate ofsoda ..... 8 Baar ton 2s = ETE RS RE i See 16 -|, Nitrate of ammonia . 1 part i AWC Rise tai. Sesion ss 1 “| From + 50° to + 4°. 46 Nitrate of ammonia .. 1 part Carbonate of soda «.. 1 From + 50°to—7°. 57 VALET Se orelactee eae aia: ss Sulphate of soda_.... | 3 parts . be Diluted nitric acid ... 2 From + 50° to — 3°, 53 Bie = LER A aig el LTT Aue Sante Sulphate of soda ..... 6 parts ~} Muriate of ammonia .. 4 & ‘ Nitrate of potash .... 2 From + 50° to — 10°. se Diluted nitric acid 4 Sulphate of soda ..... 6 parts Nitrate of ammonia ..- 5 From + 50° to — 14°} 64 Diluted nitric acid .... 4 Phosphate ofsoda .... 9 parts |p + 50° to — 12°. a Diluted nitric acid .... 4 Phosphate ofsoda ....° 9 parts Nitrate of ammonia .. 6 From + 50° to— 21°, Thee Diluted nitricacid .... 4 Sulphate of soda <.... 3 parts From+50°to0. 50 Muriatic acid ....... Sulphate of soda ..... 5 parts From 4 50° to +. 8°. 47 Diluted sulphuric acid 4 ~'N.B. If the materials are mixed at a warmer temperature than that expressed in the table, the effect will be propor- tionably greater : thus, if the-most powerful of these mix- tures be made when the air is + 85°, it will sink the ther- miometer tO. 2°. , Table contained in Mr. Walker's Publication, 1808... 179 Table 1. This Table consists of frigorific mixtures, composed of ice, with chemical salts and acids; ©? Frigorific Mixtures, wath Ice. . : Degrees of cold) Mixtures. Thermometer sinks. produced. Snow, or pounded ice, 2 parts 7 pa es Muriate of soda ..... 1 Snow, or pounded ice, 5 parts 3 Muriate of soda ..... 2 $ to — 12° * Muriate of ammonia . 1 5 pt ee PESTO Cue Ba SUN) Ae hes Snow, or poundedice, 24 parts & j Muriate of soda .,... 10 Ae pee chsh R Muriate of ammonia . 5 § Nitrate of potash .... 5 iS oR ee Nia a ce S Poems ea feta wala stack Snow, or poundedice, 12 parts | ™& Muriate of soda ..... 5 to — 25° ant Nitrate of ammonia .. 5 Diluted auipharis add 2" | From-+s2to—20). 55 Muriatic acid’ “01001 g P| From-+s20t0— 274-59) SHOW eeeclensaeoes dpa ee adh oi 62 0» iluted nitric acid este ii Murate of finie’ “71, P&T | srom-92°to— 404 12) Cryst inuratc oFiime’ PT" [rom4s20t0—504 22 Oe Sia Bas BA gone 7 parts From + 32° to —- 51° 83 N.B. The reason for the omissions in the last column of this table is, the thermometer sinking in these mixtures to the degree mentioned in the preceding column, and never lower, whatever may be the temperature of the materials at mixing. . M 2 Table {86 Collective View of all the Frigorific Mixtures, Feu Table III. / _ This Table consists of frigorific mixtures selected from the foregoing tables, and combined, so as to increase or extend cold to the extremest degrees. Combinations of Frigorific Mixtures. Desrees of coic) produced. Mixtures. Thermometer sinks. Phosphate of soda. ... 5 parts Nitrate of amnionia .. 3 “From 0° to — 34° 34. _ Diluted nitric acid .... 4 | Phosphate of soda ... 3 parts Nitrate of ammonia ..~°2 From — 34° to —50° Diluted mixed acids .. 4 3 parts sorgy oe iG Diluted nitric acid..." 8 paar dient ant ) : 8 parts i Diluted sulphuric acid From —10° to — 56° aoe nitric acid SNOVE dersiern afb =e 3 parts ; Muriate of lime i s. parts] prom + 10° to — 549, From 0° to — 66° |_— ————$ LN, Be The materials in ‘the first on are to be cooled, Srey to mixing, to the temperature required, by MIX- tures taken from either of the preceding tables, Sok +e : XXXI. No- | [ ist ] XXXI. Notices respecting New Books. Sats Second Part of the Philosophical Transactions has made its gppearance. The following are its contents : 12. Observations of a Comet, made. with a View to in- vestigate its Magnitude and the Nature of its lumination. To which is added, an Account of a new Irregularity lately perceived in the apparent Figure of the planet Saturn. By William Herschel, LL.D. F.R.S.—13. Hydraulic Investi- gations, subservient to an intended Croonian Lecture on the Motion of the Blood. By Thomas Young, M.D. For. Sec. R.S.—14. A I.etter 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 William Richard- son, D.D.—15. A Letter on the Differences in the Struc- ture of Calculi, which arise from their being formed in diffe- rent Parts of the urinary Passages; and on the Effects that are produced on them, by the internal Use of solvent Medi- cines, from Mr. William Brande, to Everard Home, Esq., F.R.S.—16. Some Observations on Mr. Brande’s Paper on Calculi. By Everard Home, Esq., F.R.S.—17. On the Changes produced in Atmospheric Air, and Oxygen Gas, by Respiration. By W. Allen, Esq., F.R.S., and W. H. Pepys, Esq., F.R.S.—18. Description of an Apparatus for the Analysis of the Compound Inflammahle Gases by 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 In- firmary, at Manchester. Communicated by Humphry Davy, Esq., Sec. R.S.—19. An Account of some Peculiarities in- the anatomical Structure of the Wombat, with Observations on the Female Organs of Generation. By Everard Home, Esq., F.R.S.—20. On the Origin and Office of the Albur- | num of Trees. In a Letter from T. A. Knight, Esq., F.R.S. to Sir Joseph Banks, Bart., K.B., P.R.S.—21. Eclipses of the Satellites of Jupiter, observed by Jobn Goldingham, Esq., F.R.S., and under-his Superintendance,. at Madras, M 3 ay Cai 182 Notices respecting New Books. in the East Indies.—g2. Electro-Chemical Researches on the Decomposition of the Earths; with Observations on the Metals obtained from the alkaline Earths, and on the Amal- gam procured from Ammonia. By Humphry Davy, Esq. Bec US) MRA: The Ninth Volume of the Transactions of the Linnean So- cietv is published, and the following are the contents: » 1. The Genus Apion of Herbst’s Natursystem considered, its Characters laid down, and many of the Species described. By the Rey. William Kirby, F.L.S.—2. Description of se- ~ veral Marine Animals found on the South Coast of Devon-— shire. By George Montagu, Esq., F.L.S.—3. An Account ~ of the Indian Badger; the Ursus indicus of Shaw’s Zodlogy. By Lieutenant Colonel Thomas Hardwicke, F.L.S.—4, A- Botanical Sketch of the Genus Conchium. By James Ed- ward Smith, M.D. F.R.S. P.L.S.—5. An Inquiry into the Genus of the Tree called by Pona Abelicea cretica. By, James Edward Smith, M.D. F.R.S.P.L.S.—6. An Inquiry into the real Dancus Gingidium of Linneus, By James Edward Smith, M.D. F.RB.S. “ph ss 287: Descriptions of Eight New British Lichens. By Dawson Turner, Esq., F.R. Ss. Ais: and L.S.—s. An Illustration of the Species of Lycium which grow wild at the Cape of Good Hope. By Sir Charles Peter Thunberg, Knight of the Order of Wasa, Professor of Botany at Upsal, F F.M.L.S.—9. Some Observations on an Insect that destroys the Wheat, supposed to be the Wire- worm. By Thomas Walford, Esq., F.A.S. and L.S. With an additional Note, by Thomas Marsham, Esq., Treas. L.S. —10.An Account of the larger and lesser Species of Horse- shoe Bats, proving them to be distinct; together with a Description of Vespertilio Barbastellus, eek in the South of Devonshire. By George Montagu, Esq., F.L.S.—11. De- Senphian. of two new Saccn of Didelphis from Van Die- men’s Land. By G. P. Harris, Esq. Communicated by the Right Honourable Sir Joseph Banks, Bart. K.B. Pres. R.S. H.M.L.S.—12. Description of a Species of Dimorpha. By Edward Rudge, Esq., F.R.S. and L.S.—13. Some interest- ing “Additions to the Natural History of Faleo cyaneus and PYSatoPe2 - Nottces respecting New Books. (183 pygargus, together with Remarks on some other British Birds. By George Montagu, Esq., F.L.S.—14. An Ac- count of some new Species of Piper, with a few cursory Observations on the Genus. By Mr. John Vaughan Thomp- son. Communicated by the Right Hon Lord Seaforth, F.R.S. and L.S.—15. An Inquiry into the Structure of Seeds, and especially into the true Nature of that Part called by Geert- ner the Vitellus. By James Edward Smith, M.D. F.R. S. P.L.S.—16. 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.— 17. Observations respecting several British Species of Hiera= cium. By James Edward Smith, M.D. F.R.S. P.L.S.— 18. Specific Characters of the Decandrous Papilionaceous Plants of New Holland. By James Edward Smith, M.D. F.R.S. P.L.S.—ig. 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.—2o. Characters of Hookeria, a new Genus of Mosses, with De- scriptions of Ten Species. By James Edward Smith, M.D. F.R.S. P.L.S.—21. Description of Notoclea, a new Genus. of Coleopierous Insects from New Holland. By Thomas Marsham, Esq., Tr. L.S.—22. Some Remarks on the Plants now referred to Sophora, with Characters of the Genus ee By R. A. Salisbury, Esq., F.R.S. and L.S.—23. Characters of Platylobium, Bossiza, and of a new ence named Poiretia. By James Edward Smith, M.D. F.R.S. P.L.S.—24. Musci Nepalenses ; or Descriptions. of several new Mosses from Nepal. By William. Jackson Hooker, Esq., F.L.S.—25. Extracts from the. -Minute- Book of the Linnean Society of London.—Catalogue of ihe Library of the Linnean Society.—List of Donors to the Library of the Linnean Society. The Chemical Catechism, with Notes, Ilustrations,. andl Experiments. By SAMUEL Parkers, General Manufe ac~ turing Chemist. 8vo. Third Edition. \ ea ae We have before had occasion to commend iti work, as M4 bone Es) 184 New Books.—Royal Society. being well calculated to initiate young people into a know- ledge of the subject of which it treats. The favourable re- ception it has had with the public, justifies the opinion we gave of the former editions. The present one has fresh claims to praise. We have exam:ned it with some degree of care, and are happy to find that the author’s industry has - kept pace with the discoveries that have been made in this interesting and useful branch of knowledge. Parents and teachers will derive assistance from this.work, in their efforts to impress upon young minds, along with what is highly amusing and gratifying to an inquisitive pupil, some ideas of that power, wisdom and goodness which pervades the universe—an aim of which the author seems never to have lost sight throughout his pages. Review of Publications of Art. Nos. 1, 2, and 3, The above is the title of a quarterly publication confess- edly written as a successor to The Artist, a periodical work which has now ceased, and from which we recently pre- sented the readers of the Philosophical Magazine with some interesting Essays. » ’ The editors of the Review row before us have ably taken up the functions of their predecessors 1 in The Artist, and it is but justice to give tt as our opinion, that bitherta their labours have been distinguished by sound judzement, and more than common critical acumen. Their zeal for the en- ‘couragement of the imitative arts is evident from the in- trepid manner in which they discharge what they conceive to be their duty, in censuring the tendency of modern artists to flatter the prevailing preiudices of fashion at the SEpEREE of true taste and sound judgement. XXII. Proceedings of Learned Societies. ROYAL SOCIETY. Tus society assembled after the summer vacation on Thursday, Nov.10th, 1808,the right hon, Sir Joseph Banks, president, in the chair, The secretary read a summary of 13 | M. de ~ Royal Society. 183 M..de Luc’s paper on the action of electricity and galvanism, or the electroseopical agency of electric and galvanic mat- ter. Inthis paper M. de Luc proved that neither electricity nor galvanism have any chemical action unless when com- bined with other bodies: that the galvanic and electric fluid are essenually the same, as zinc has the greatest affinity tor electricity, and silver next to it; so that, when these two metals are separated by moistened paper, the reciprocal elec- tric attraction is called: into action, in the same manner as by the friction of the electric machine; and that it is the action and re-action of this attraction which have given birth to the appellation of positive and negative electricity, The simple electric or galvanic fluid, he also stated, passes through bodies without producing any chemical changes, unless the bodies were previously prepared and the electricity highly concentrated. November 17—24. The Croonian Jecture on the muscles of the heart and the motion of the blood, by Dr. Young, {®oreign Sec. R.S.) was read. This lecture was a continua- tion of the auther’s former paper on the motion of fluids in elastic or fiexible tubes, which appears in the first part of the Transactions of the present year. Dr. Y. took a view of the nature of fever, and its effects on the blood, as well as of blood-letting, which he considered as generally in- adequate to produce the effect intended. He.also gavea theory of mortification, which the Germans calla ‘ cold buming.” A paper by Mr. Childers was read, containing some ob- servations and experiments on the most conannnnieal means of constructing very powerful galvanic batteries. From.a number of experiments performed in the presence of Mr. Davy and others, Mr. Childers concludes, that if #t is de- sired to act on substances which are non-conductors-of gal- vanism, very broad plates of copper and zinc are preferable; but if on substances which are good-conduciors, ‘then nar row plates in greater numbers will be found most convent- ent: the former continue to emit fluid for forty- -cight hours, the latter for a much shorter time; but they emit it much quicker, and are better adapted to ae experiments. Mr. 2 C. also ss ! 186 Wernerian Natural History Society. C. also recommends the-having the plates moveable instead of being soldered together, as’ the trough can be much easier cleared out after ‘using it. He recommends to make the troughs of glass or raed eR" ’s ware, im preference to the materials hitherto euipleged: WERNER IAN NATURAL HISTORY ‘SOCIETY. At the meeting of the Wernerian Natural History So- ciety, Ist August, Dr. James Ogilby of Dublin read a very interesting account of the mineralogy of East Lothian, which appeared to have been drawn up from a series of observa- tions, made with great skill. and was illustrated by a suite of 350 specimens laid upon the table. As the county is in general deeply covered with soil, and profusely clothed with vegetables, the determination of the different formations must have been a work of considerable labour; and the skill, judgement and perseverance of the observer must have. been frequently put to the trial. The docter, after describ- mg the physiognomy or external aspect of the county, gave a particular account of the different formations of which Tt is composed. They are as follows :—Transition ; Indepen- dent Coal; Newest Floetztrap: and Alluvial. When de- scribing the different transition rocks, he alluded particular- ly to the supposed granite of Fassnet, (described by profes- sor Playfair in his Illustrations of the Huttonian theory,) which he proved to be a stratified bed of transition green- stone. The description of the rocks of the newest floetz- trap -formation was particularly interesting, not only on ac- count of the beautiful transitions he pointed out, but ‘also as it proved the existence of a considerable tract of these’ rocks in Scotland, where their occurrence had been disput- ed. He enumerated and described the following members -of this formation :—trap-tuff; amvgdaloid : clay-stone; ba- salt; porphyry-slate ; and porphyry-slate inclining to green- stone. He found the trap-tuff, which is a coarse mechant- -cal deposite, forming the lowest member of the series, and resting immediately on the coal-formation: on this tuff rests amygdaloid containing fragments: above this ‘amyg- dalotd is common amygdaloid free of fragments ; this, ym its, Wernerian Natural History. Society. is] jis turn,.is covered with basalt: the basalt gradually passes into, and is covered with, porphyry-slate : and the porphyry- slate, in some instances, appears to pass into greenstone, which forms the uppermost portion of the formation :—So that we have thus a beautiful series of transitions from the coarse mechanical, to fine chemical; that is, from trap-tuff to porphyry-slate inclining to greenstone. The doctor also remarked, that the amygdaloid contains crystals of felspar which have an earthy aspect; the basalt, crystals of felspar possessing the characters of common felspar; and the por- phyry-slate, glassy felspar ;—facts which coincide with, and -are illustrative of the increasing fineness of the solution, from the oldest to the newest members of the formation. - In the course of his paper, the doctor gave distinct and_ satisfac- tory answers to the following queries, which had been pro- posed by professor Jameson :—1i. Does the Bass rock in the Frith of Forth belong to the newest floetz-trap formation ? g. Does the sienitic greenstone of Fassnet in East Lothian belong to the transition rocks, or to the newest floctz-trap formation? 3. Are the geognostic relations of the porphyry - ‘slate, or clinkstene-porphyry, of East Lothian, the same as in other countries? The doctor.announced his intention of reading, at the next meeting of the society, a description of the different veins that occur in East Lothian, and of giving a short slatement of the geognostical and gceconomi- cal inferences to be deduced from the appearances which he has investigated with so mich care. It is indeed only by investigations like those of Dr. Ogilby, that we obtain any certainty respecting the mineral treasures of a country ; and -such alone can afford us data for a legitimate theory of the formation of the globe. At the same meeting, a communication from. colonel Montagu was read, describing a new species of Fasciola, of a red colour, and about an inch lony, which sometimes Jodges in the trachea of chickens, and which the colonel found to be the occasion of the distemper called the. gapes, so fatal to these useful tenants of, the poultry-yard.. The knowledge of the true cause of this malady will, itis hoped, soon be followed by the discovery of a specific cure: -in the mcan BB Wernerian Natural History Society. mean time, a very simple popular remedy is employed in Devonshire : the meat of the chicks (barley or oat meal) is merely mixed up wita urine, in place of water, and this prescription is very gencrally attended with the best effects. At the mecting of this Society on the 12th of November, ‘theRey. Andrew Pidieaau: minister of St. Mungo, Dumfries- shire, read Observations on Meteorological: Tables, with a Description of a new Anemometer. After some general remarks on the importance of meteorological observations, and on the merits and defects of registers of the weather, &c. he pointed out what he. considered to be the best form of a meteorological journal, and then described the external form and internal structure of an extensive and complete meteorological observatory, and enumerated about twenty different instruments which ought to’ find a place in eyery establishment of that kind. The anemometer which he de- scribed will, by a very simple and ingenious arrangement of parts, enable the most common observer to ascertain the ve- Jocity of the wind with perfect accuracy. . At the same meeting, the Rev. John Fleming, F.A.S. Ed., minister of Bressay in Shetland, (who has for some: time past been engaged in examining the mineralogy of those remote islands,) communicated an interesting account of the geognostie relations of the rocks in the islands of Unst and rane Stour. i ' After a general account of the position, extent and exter- nal appearance of the island of Unst, he next described the different rocks of which it is composed, in’the order of their relative antiquity, and remarked that their general position is from. S.W. to N.E. The rocks ‘are gneiss, mica-slate, clay-slate, limestone, hornblende-roeck, potstone, and ser- pentine. The gzeiss in some places’ appeared to alternate with the oldest mica-slate, and in others to contain beds of hornblende-rock. The mica-slate, which is the most abun- _ dant rock in the island, is traversed by numerdus contem- -poraneous veins of quartz, and also of felspar, and. passes distinetly into clay-slate. It contains beds of hornblende- rock and of hmestone. The clay-slate occurs but sparing- ly. The potstone usually accompanies the serpentine, . The serpentine eee eee Wernerian Natural History Society. 18g serpentine occurs in great abundance, in beds, in the oldest clay-slate and newest mica-slate, and hence must be referred to the oldest or first serpentine formation of Werner. The island of Papa Stour, situated on the west coast of the Mainland, (as the largest of the islands is called,} con- tains no primitive rocks, but appears to be entirely composed of floetz rocks. These are conglomerate, greenstone, clay- stone, porphyritic stone, hornstone, (perhaps clinkstone, ) anid sandstone. The sandstone, as appears from observa- tions made in this island and other parts of Shetland, pro- bably belangs to the oldest coal-formation: it is uniformly Situated below the other rocks above mentioned. As Mr. Fleming announced his tention of again ex- amining the dad of the Shetland islands, and ‘of construct- "ing mineralogical maps of them, in which the rocks should _ be laid down according to their relative antiquity and extent, much valuable information may be expected. At the meeting of the Society on the 19th of November, Mr. Mackenzie, jun. of Applecross read a short Account of the Coal-formation in the Vieimtty of Durham. From the precise and accurate description communicated by this gen- tleman, the rocks appear to belong to the oldest ‘ coal-for- mation of Werner. During thé course of his observations he explained what is ealled the creep by miners, and exhi- bited specimens of-the different rocks, with a section of the coal-mine of Kipia, in which both the miners’ and the Sei- entific names of the different strata were inserted. At the same meeting, Dr. Ogilby, of Dublin, read the continuation of his Mineralogical Description of East Lo- thian, describing the different veins which he observed’ in that tract of country. These he considered as of three dif- ferent periods of formation, viz. 1. Such as are derived from partial formations subsequent to the floetz-trap,which are of rare occurrence; 2. Veins of the different rocks of the forma- tion penetrating the older beds; and 3. Those of contém- poraneous origin. He then enumeiated and described, ac- cording. to the manner of Werner, veins of ¢teenstone, Vey aint heavy-spar, and ealc- -spar. ; At 190 IVernerian Natural Histary Society.—Dublin Society. At this meeting, also, Mr. P. Neill read an account of 2. great Sea Snake, lately cast ashore 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 cireumstance to his, - brother, Gilbert Laing, Esq., advocate at. Edinburgh, on whose property the animal had been cast. ‘Through this au- thentic channel Mr. Neill received his information. The body measured fifty-five fect in length, and the circumfe- rence of the thickest part might be equal to the girth of an Orkney pony. The head was not larger than that of a seal, and was furnished with two blow holes... From the back a number of filaments (resembling in texture the _fishing- tackle known by the name. of. silk-worm gut) hung down like a mane. On each side of the body were three large fins, shaped like paws, and jointed. The body was unluckily knocked to pieces bya. tempest; but the fragments have been collected by Mr. Laing, and are to be transmitted to the’ museum at Edinburgh. Mr. Neill concluded, with re- marking, that no doubt could be entertained that this was the kind of animal described by Ramus, Egede, and Pon- — toppidan, but which scientific and systematic naturalists had hitherto rejected as spurious and ideal. | DUBLIN SOCIETY. A letter, dated Manchester, and signed John Bradbury, was laid before the Society, at their late meeting, stat- ing that the proprietors of the Liverpool Botanic Garden bad resolved on forming an establishment at New Orleans, Ainerica, with a view tocollect the plants of Kentucky and Louisiana, and to transmit to England living duplicates of the plants which should be so collected and multiplied ‘on such establishment; and desiring to be informed if the Dublin Society would, in consideration of green specimens of the same, contribute to the expense, their quota not to exceed 100l, per annum. The secretary laid before the Society a list of several va- luable West India plants, pres ee to the Society by carta Burgh. it 3 XXXII. Zee fgtotwd XXXII. Intelligence and Miscellaneous Articles. ON MR. KERR’S CLAIMS, AND ON THE NATURE OF THE EARTHS. W: have received a second communication with the sig= nature O., and bearing the above title. Had it come with the author’s name, we should have given it insertion. | But we cannot permit, in our pages, on anonymous authority, a repetition of such statements, after they have heen once answered. An honourable assailant (and we mean not to in- sinuate that O. will show himself otherwise) cam have no ob- jection to avow himself. IfQ. hesitate éo give his own name, he cannot be surprised that we should hesitate ¢o /end ours. For the same reason we must refuse insertion to a com- munication signed S. To this communication we have also to object, that several of the alleged facts are incorrect, and consequently the conclusions unfounded. Another correspondent, A. C., has sent us an article en- titled “* On some points of philosophical criticism.” {t con- tains remarks which, might be fair, were he replying to claims set up by Mr. Kerr himself, but which, as circum- stances stand at the present moment, might savour of illi- berality towards that gentleman. Impartiality therefore de- mands that we refuse this anonymous communication a place in our Magazine. A Comet was too hastily reported in our last to be visible in our hemisphere. The supposed comet proves to be the nebulze in Andromeda. LECTURES. Royal Institution.—The following arrangement is made for the Lectures of the ensuing Season ; they will commence on Saturday the 17th of December, with an {ntroductory Lecture by Mr. Davy. Experimental Chemistry, and Electro- Chemical Science, by Humphry Davy, Esq., ae R.S: | Botany, by James Edward Smith, MD. F.R.S. P.LS. Astronomy, by John Pond, Esq: HaRsSe alt Grecian History and Historians, by ‘the Rev, William Crowe, Public Orator at the University of Oxford, Perspective, by Mr. John George Wood. Music, by Mr. Samuel Wesley. “ METEORQ= ~ Days of the Wionth. Nov. 10 METEOROLOGICAL TABLE, Meteorology. | ~ By Mr. Canzy, oF THE STRAND, - For November 1808. Thermometer. eo \ ee % Oona af el. |e | Height jos & 2 SE 5 dtthlthe Barom.| D/2..6 Qets |r =| Inches. {tye 3 2 aid, aaa ig -) = a Soe 44° 50°| 29-44 34 57 46 "45 2 44 45 “7) 21 46 47 | 30°20 27 45 46 152 25 47 46 28 18 46 46 "] 26 46 44 "05 25 42 40 ‘08 2 36 34 | 29°89 26 32 42 “80 30 42 43 69 19 43- 44 *62 15 47 46 *63 a) 46 45 °70 26 46 44 ‘8h 8) 3 40 | 30°10 15 39 35 -10 10 31 32 “11 5 34 46 | 29°90 6 50 51 50 25 51 48 "25 25 47 AAW |e DBn Ry O 35 37 | 29°54 oe 36 46 = ifs, 6 53 42 °85 10 39 47 | 30°20 AZ 47 46 BY fe 9 49 46 | °18 8 49 48 | 29°98 os 48 53 “90 6 Weather. Pair Shower Fair. : i\Cloudy Cloudy Cloudy Cloudy Cloudy Fair Foose Cloudy Fair Fair Rain and a falt of snow to- wards the morning Fair Fair Fair Fair Cloudy Cloudy Cloudy Cloudy N.B. The Barometer’s height is taken at one o'clock. a fe Sigavi joloovtasls . aM tr XXXIV. Se 0 sh be rhe on Sri cape “empl of the Earths ; wiih Olservations on the Metals obtained from the alkaline Earths, and on the Amalgam, procured, from Ammonia. By Humeunry Davy, Esa, Sanne Gs she ae M.R.ILA. Prof. Chem. R.I.* : I. Introduction. Tx the era Transactions es 1807, Part I. + and Y@08, Part I. +, I have detailed the general methods of de- composition by electricity, and stated various new facts ob- tained in consequence of the application of them. The results of the experiments on potash and soda, as T stated in, my Jast communication to the Society, afforded’ me the strongest hopes of being able to effect the decom-, position both of the alkaline and common earths ; and the phznomena obtained in the first imperfect trials made upon those bodies, countenanced the ideas that had obtained from the earliest periods of chemistry, of their being metallic i in their nature §. Many * From Philosophical Transactions for 1808: Part II. ae +SeePhil. Mag. vol. xxviii. p. 1, 104, 220. + Ibid. vol. xxxii. p. 1, 97, 146.' § Beccher is the first chemist, as far as my. reading informs.me, who di-. stinetly pounted cut the relations of metals to earthy substances; See Phys. subt. Lipsiz, 4to, p. 61. He was followed by Stahl, who has given the doc- trine a mote perfect form. Leecher's idea was that of an universal elementary earth, which, by uniting to an initiammaeble earth, produced all the metals, and under other modifications formed stones. Stahl admitted distinct earths which he suppesed might be converted into metals by combining with phlo- giston; see Stahl Fundament. Chym. p.9, 4to, and Conspect. Chem. 1, 77, 4to.—Neuman gives an account of an elaborate series of unsuccessful experi- ments which he made to obiain a metal irom quicklime. Lewi’s Neuman’s Chem. Works, 2d. edit. vol. i. p. 15. Tne earlier English chemical. philoso- ph 1ers seem to have ad seit the opinion of the possibilicy of the preduction of metals fron: common earthy substances; See Boyle, vol. i. 4to, p. 564, and Grew, Anatomy of Plan‘s, lec. ii. p. 242. Eut these notions were founded upon 4 kind of alchemical hypothesis of a general power in nature of trans- muting one species of matter into another. ‘Towards the end of the last cene tury the doctrine was advanced in a more philosophical form; Bergmai suse pected barytes to bea metallic calx, Praf. Sciagrap. Reg. Min. and Opusc. iv. p.212. Baron supported the idea of the probability of alumine being a metallic substance, See Annales de Chimie, vol. x. p. 257.— Lavoisier extended these notions, by supposing the other earths metallic oxides, Elements, 2d edit. Kerr's translation, p. 217. The general ety ‘was closed by the as- Vol. 32..NMo, 127, Dec. 1808, N Re ' sertion \ ee, Electrochemical Researches on Many difficulties however occurred in the way of obtain ing complete evidence on this subject: and the pursuit of the inquiry has required much labour and a considerable de- votion of time, and has demanded more refined and com- plicated processes than those which had succeeded with thé fixed alkalis. The earths, like the fixed alkalis, are non-conductors of electricity ; ; but the fixed alkalis become conducting by fu-. sion : the infusible nature of the earths, however, rendered it impossible to operate upon them in this state: the strong affinity of their bases for oxygen, made it unavailing to act upon them in solution in water; and the only methods that proved successful, were those a operating upon them by electricity in some of. their combinations, or of combining them at the moment of their decomposition by electricity, i metallic alloys, so as to obtain evidences of their nature and properties. T delayed for some time laying an account of many of the principal results which T obtained before the Society, in the hopes. of being able to render them more distinct and satis- factory ; but finding that for this end a more powerful bat- tery, and more perfect apparatus than I have a prospect of seeing very soon constructed, will be required, I have ven- tured to bring forwards the investigation in its present im- perfect state; and I shall prefer the imputation of having published unfinished labours, to that of having concealed any new facts from the scientific world, which may tend to assist the progress of chemical knowledge. TL. Methods employed for Decomposing the alkaline Earths. Barytes, strontites, and lime, slightly moistened, were, sertion of Tondi and Ruprecht, that the. earths might be reduced by char- coal; and the accurate researches of Klaproth and Savaresi, who proved by the most decisive experiments, that the metals taken for the bases of the- earths were phosphurets of iron, obtained from the: bone ashes and other materials employed in the experiment, Annales de Chimie, vol. viil’ P. 18,. and vol. x. p. 257, 275. Amidst all these hypotheses, potash and soda ' were’ sever considered as metallic in their nature: Lavoisier supposed themito con- tain azote; nor at thit time were there any analogies to. lead that acute ‘philosopher to a happier conjecture. electrified the Decomposition of the Earths, €&c. 195 electrified by iron wires under naphtha, by the same methods, and with the same powers as those employed for the de- composition of the fixed alkalis*. In these cases, gas was copiously evolved, which was inflammable; and the earths where in contact with the negative metallic wires became dark coloured, and exhibited small points having a metallic lustre, which, when exposed to air, gradually became white; they became white likewise when plunged under water, and . when examined in this experiment by a magnifier, a greenish powder seemed to separate from them, and small globules of gas were disengaged. Tn these cases there was great reason to believe that the earths had been decomposed; and that their bases: had combined with the iron, so as to form alloys decomposable by the oxygen of air or water; but the indistinctness of the effect, and the complicated circumstances required for it, were such as to compel me to form other plans of operation. | The strong attraction of potassium for oxygen, induced me _ to try whether this body might not detach the oxygen from the earths, in the same manner as charcoal decomposes the common metallic oxides. I heated potassium in contact with dry pure lime, barytes, strontites, and magnesia, in tubes of plate glass; but‘as I was obliged to use very small quantities, and as I could not raise the heat to ignition without fusing the glass, I obtained in this way no good results. The potassium appeared to act upon the earths and on the glass, and dark brown substances were obtained, which evolved gas from water; but no di- stinct metallic globules could be procured: from these cir- cumstances, and other like circumstances, it seemed pro- bable, that though potassium may partially de-oxygenate the earths, yet its affinity for oxygen, at least at the tempera- ture which I employed, is not sufficient to effect their de- composition. I made mixtures of dry potash in excess and dry harytes, lime; strontites, and magnesia, brought them into fusion, and acted upon them in the voltaic circuit in the same man- * See Phil. Mag. vol. xxxii. p. 4 Ne ; ner 196 he Electrochemical Researches on ner as that I employed for obtaining the metals of the alka- lis. My hopes were, that the potassium and-the metals. of the earths might be de-oxygenated at the same time, and enter into a laee a in alloy. In this way of operating, the results were more distinct than in the last: metallic substances appeared, less fusible than potassium, which burnt the instant after they had formed, and which by burning produced a mixture of potash and the earth employed ; I endeavoured to form them under | naphtha, but without much success. To produce the result at all, required a charge by the action of nitric acid, which the state of the batteries did not permit me often to employ *; and the metal was generated only in very minute films, which could not be detached by fusion, and which were instantly destroyed by exposure to air. | I had found in my researches upon potassium, that when a mixture of potash and the oxides of mercury, tin, or lead, was’electrified in the Voltaic circuit, the decomposition was very rapid, and an amalgam, or an alloy of potassium, was obtained ; the attraction between the common. metals and thé potassium apparently accelerating the separation of the oxygen. ; The idea that a similar kind of action might assist the de- composition of the alkaline earths, Sideed me to electrify mixtures of these bodies and the oxide of tin, of iron, of lead, of silver, and of mercury; and these operations. were- far more satisfactory than any of the others. ’ * The power of this combination, though it consisted of one hundred plates of copper and zine of six inches, and one hundred and fifty of four inches, at this time was not more than equal to that of a newly constructed apparatus of one hundred and fifty of four inches. It had been made for the demon- strations in the Theatre of the Royal Institution in 1803; and since that time’ had been constantly employed ip’ the annual course of lectures; and had served in different parts, for the numerous experiments on the decomposition of bodies by electricity, detailed in the Bakerian Lectures for 1806 and 1807, and anumber of the plates were destroyed by corrosion. ‘I mention these circumstances, because many chémists have been deterred from pursuing ex- periments on the decomposition of the alkalis and the earths, under the idea that a very powerful combination was required for the effect. This, how- ever, is far from being the case; all the experiments detailed in the text may be repeated by means of a Voltaic battery, containing from one hundred ‘o one hundred and fifty plates cf four or six inches. A mix- the Decomposition of the Earths, 8c. 197 A mixture of two-thirds of barytes and one-third of oxide of silver very slightly moistened was electrified by iron wires 5. an effervescence took place at both points of contact, anda minute quantity of a substance, possessing the whiteness of silver, formed at the negative point. When the iron wike.to. which this substance adhered was plunged into water con~ taining a little alum in solution, gas was disengaged, which proved to be hydrogen; and white clouds which were found to be sulphate of barytes, descended from the point of the wire. A-mixture of barytes and red oxide of mercury, in the same proportions, was electrified in the same manner. A small mass of solid amalgam adhered to the negative wire, which evidently contained a substance, that produced barytes by exposure to air, with the absorption of oxygen ; and which occasioned the evolution of hydrogen from water, leaving pure mercury, and producing a solution of barytes. — - Mistures of lime, strontites, magnesia, and red oxide of mercury, treated in the same manner, gave similar amal- gams, from which the alkaline earths were regenerated by the action of air or water, with like pheenomena; but the quantities of metallic substances obtained were exceedingly minute; they appeared as mere superficial formations sur- rounding the point of the wire, nor did they increase after the first few minutes of electrization, even when the process was carried on for some hours. These experiments were made previous to April, 1808, at which time the batteries were so much injured by constant use, as no longer to form an efficient combination. ‘The in- quiry was suspended for a short time: but in May I was enabled to resume it, by employing 4 new and much more powerful combination, constructed in the Jaboratory of the Royal Institution, and censisting of five hundred pairs of double plates of six inches square. When I attempted to obtain amalgams with this appa- ratus, the transmitting wires being of platina, of about =1,th of an inch in diameter; the heat generated was so great as to burn both the mercury and basis of the amalgam at the momient of its formation; and when by extending the sur- N3 “\ faces | 198 _ Electrochemical Researches on “faces ofthe conductors, this’ power of ignition was modified, yet still the amalgam was only produced in thin films, and I could not obtain lobules sufficiently large to submit to distillation. When : the transmitting wires were of iron of the same thickness, the iron acquired the temperature of fenition, and combined with the bases of the earths in pre- ference to the mercury, and metallic alloys of a dark gray colour were obtained, which acted on water with the evo- lution of hydrogen, and were converted into oxide of iron, and alkaline earths. Whilst I was engaged in these experiments, in the be- ginning of June, I received a letter from Professor Berzelius of Stockholm, in which he informed me that, in conjunction» with Dr. Pontin, he had succeeded in decomposing barytes and lime, by negatively electrifymg mercury in contact with them, and that in this way he had obtained amalgams of the. metals of these earths. I immediately repeated these operations with perfect suc- cess; a clobule of mercury, electrified by the power of the battery of 500, weakly charged, was made to act upon a surface of slightly moistened barytes, fixed upon a plate of platina. The mercury gradually became less fluid, and after a few minutes was found covered with a white film of ba- tytes; and when the amalgam was thrown into water, hy drogen was disengaged, the mercury remained free, and a solution of barytes was formed. The result with lime, as these gentlemen had stated, was precisely analogous. That the same happy methods must succeed with strontites and magnesia, it was not easy to doubt, and I quickly tried the experiment. From strontites I obtained a very rapid result; but from magnesia, in the first trials, no amalgam could be procured. By continuing the process, however, for a longer time, and keeping the earth continually moist, at last a combination of the basis with mercury was obtained, which ‘slowly pro- duced magnesia by absorption of oxy gen from air, or by the action of water. All these amalgams I found be ey be preserved fora con- siderable ~ the Decomposition of the Earths, €8c. 199 siderable period under naphtha. In a length of time, how- ‘ever, they became covered with a white crust under this fluid. When exposed to air, a very few minutes only were required for the oxygenation of the bases of the earths. In water the amalgam of barytes was most rapidly decomposed» that of strontites and that of lime next in order: but the amaloam from magnesia, as might be expected from the weak affinity of the earth for water, very slowly changed ; when a little sulphuric acid was added to the water : how- ever, the evolution of hydrogen, and the production and so- lution of magnesia were exceedingly rapid, and the mercury soon remained free. I was inclined to believe that one reason why magnesia was less easy to metallize than the other alkaline earths, was its insolubility in water, which would prevent it from being presented in the nascent state, detached from its solution at the negative surface. On this idea I tried the experinient, using moistened sulphate of magnesia, instead of the pure earth ; and I found that the amalgam was much sooner ob- tained. Here the magnesia was attracted from the sulphuric acid, and probably deoxygenated and combined with the quicksilver at the same instant. The amalgams of the other bases of the alkaline earths, could, I found, be obtained inthe same manner from their saline compounds. I tried in this way very successfully, muriate and sulphate of lime, the imuriate of strontites, and of barytes, and ni- trate of barytes. The earths separated at the deoxygenating surface, there seemed instantly to undergo decomposition, and seized upon by the mercury, were in some measure de- fended from the action of air, and from the contact of water, arid preserved by their strong attraction for this metal. III. Attempts to procure the Metals of the alkaline Earths ; and on their Properties. ; To procure quantities of amalgams sufficient for distilla- tion, I combined the methods I had before employed, with those of M. M. Berzelius and Pontin. The earths were slightly moistened, and mixed with one N4 third .200 as 4 Electrochemical Researches on third of red oxide of mercury, the mixture was placed of a Plate of platina, a cavity was made in the upper part of it to receive a globule of mercury, of from fifty to sixty grains in “weight, the whole was covered hy a film of naphtha, and the plate was made positive, and the mercury negative, by a proper communication with the battery of five hundred. The amalgams obtained in this way were distilled tubes of Hae glass, or in some cases in tubes of common. glass. These tubes were bent in the middle, and the ex- tremities were enlarged, and rendered globular by blowing, ,S9 as to serve the purposes of a retort shal receiver. The tube after the amalgam had been introduced, was filled with naphtha, which was aftcrwards expelled by boil- “ing, through a small orifice in the end corresponding to the receiver, de a was hermetically sealed when the tube con- tained nothing but the vapour ef naphiba, and the amaleam. _I found immediately that the mercury rose pure by distil- lation from the amalgam, and it was very easy to separate a part of it; but to obtain a complete decomposition was very difficult. : For this nearly a red heat was required, and at a red heat the bases of the earths instantly acted upon the glass, and became oxygenated. When the tube was large in propor- tion to the quantity of anialgam, the vapour of the naphtha furnished oxygen sufficient to destroy: part of the bases : and when a small tube was employed, it was difficult to heat the part used as a retort sufficient to drive off the whole of the mercury from the basis, without raising too highly the tem- perature of the part serving for the receiver, so as to burst the tube *. In consequence of these difficulties, in a multitude of trials, I obtained only a very jew successful results, and4n no case could I be absolutely certain that there was not a minute portion of mercury still in combination with the metals of the earths, Tn the best result that I sce wis from the distillation of ®* When the quantity of the amalgam was about fifty or sixty grains, I. found that the tube could not be conveniently less than one-sixth of an inch ~ jn diameter, and of the capacity of about half a cubic inch. the the Decomposition of the Earths, &c. - 201. the amalgam of barytes, the residuum appeared as a white metal of the colour of silver. It was fixed at all common temperatures, hut became fluid at a heat below redness, and did not rise in vapour when heated to redness, in a tube of plate glass, but acted violently upon the glass, producing a black mass, which seemed to contain barytes, and a fixed alkaline basis, in the first degree of oxygenation *. When * From this fact, compared with other facts that have been stated, p. 195, it may be conjectured, that the basis of barytes has a higher affinity for oxy- gen than sodium ; and hence, probably, the bases of the earths will be more powerful instruments for detecting oxygen, than the bases of the alkalis. I have tried a number of experiments on the action of potassium on bodies supposed simple, and on the undecompounded acids. From the aflinity of the metal for oxygen, and of the acid for the substance formed, I had enter- tained the greatest hopes of success. It would be inconsistent with the object of this paper to enter into a full detail of the methods of operation; I hope to be able to state them fully to the Society at a future time, when they shall be elucidated by further researches; I shall now merely mention the general results, to show that I have not been tardy in employing the means which. “were in my power, towards effecting these important objects. When potassium was heated in muriatic acid gas, as dry as it could be ob- tained by common chemical means, there was a violent chemical action with ignition; and when the potassium was in sufficient quantity, the muriatic acid gas wholly disappeared, and from one-third to one-fourth of its volume of hydrogen was evolved, and muriate of potash was formed. On fluoric acid gas, which had been in contact with glass, the potassium produced a simiar effect; but the quantity of hydregen generated was only one-sixth or one-seventh of the volume of gas, and a white mass was formed, which principally consisted of fiuate of potash and silex, but which emitted fumes of fluoric acid when exposed to air. When boracie acid, prepared in the usual manner, that had been ignited, was heated ina gold tube with potassium, a very minute quantity of gas only was liberated, which was hydrogen, mixed with nitrogen (the last probably from the common air in the tube); borate of potash was formed, and a black substance, which became white by exposure to air. In all these instances there is great reason to believe that the hydrogen was produced from the water adhering to the acids; and the different proportions of it in the different cases, area strong proof of this opinion. Admitting this idea, it seems that muriatic acid gas must contain at least one-eighth or one- tenth of its weight of water; and that the water oxygenates in the experi- ment a quantity of potassium, suflicient to absorb the whole of the acid. In the cases of fluoric and boracic acids, there is probably a decomposition of these bodies; the black substance produced from the boracic acid is similar * to that which I had obtaimed from it by electricity. The quantities that I have operated upon, have been as yet too small to enable me to separate and exainine 202 Electrochemical Researches on | When exposed to air, it repidly tarnished, and fell into &. white powder, which was barytes. When this process was conducted in a small portion of air, the oxygen was found absorbed, and the nitrogen unaltered; when a portion of it svas introduced into water, it acted upon it with great vio- Jence and sunk to the bottom, producing in it barytes ; and hydrogen was generated. The quantities in which I obtained it were too minute for me to be able to examine correctly, » either its physical or chemical properties. It sunk rapidly in water, and even in sulphuric acid, though surrounded by globules of hydrogen, equal to two or three times its volume 5 from which it seems probable, that it cannot be less than four or five times as heavy as water. It flattened by pres- sure, but required a considerable force for this effect. The metal from strontites sunk in sulphuric acid, and ex- hibited the same characters as that from barytes, except in producing strontites by oxidation. The metal from lime, I have never been able to examine exposed to air or under naphtha. In the case in which I was able to distil the quicksilver from it to the greatest extent, the tube unfortunately broke, whilst warm; and at the mo- ment that the air entcred, the metal, which had the colour and lustre of silver, instantly took fire, and burnt with an intense white licht into quicklime. The metal roth macnesia seemed to act upon the glass, #vén before the whole of the quicksilver was distilled from it. Jn an experiment in which I stopped the process before the mercury was entirely driven off, it appeared as a solid, examine the products; and till this is done, no ultimate conclusion can be drawn. hy The action of potassium upon muriatic acid gas, indicatesa much larger quantity of water in this substance, than the action of electricity in Dr. Henry’s elaborate experiments; but in the one instance the.acid enters sito a _ solid salt, and in the other it remains acriform ; and the difficulty ef decompo- sition by electricity, must increase in proportion as the quaytity of water dimi- nishes, so that at the apparent maximum of electrical effect, there isno reason to suppose the gas free from water. Those persons who have supposed hydrogen to be the basis of muriatic acid may, perhaps, give another solution of the phenomena, and consider the experiment I have detailed as a proof of this epinien. 3 having the Decomposition of the Earths, &c. 203 having the same whiteness and lustre as the other metals of the earths. [t sunk rapidly in water, though surrounded by globules of gas, producing magnesia, and quickly changed in air, becoming covered with a white’ crust, and falling” into a fine powder, which proved to be magnesia. In several cases in which amalgams of the metals of the earths, containing only a small. quantity of mercury were obtained, I exposed them to air ona delicate balance, and always found that during the conversion of metal into i there was a eansiderablba increase of weight. [ endeavoured to ascertain the propertions of oxygen, und bases, in barytes and strontites, by heating amalgams of - ahem in tubes filled with oxygen, but without success. [ satisfied myself, however, that when the metals of the earth were burned in a small quantity of air they absorbed oxygen, gained weight in the process, and were in the highly caustit: or unslacked state; for they produced strong heat by the contact of water, and did not effervesce during their solution in acids, The evidence for the couiporitinn of the alkaline earths is then of the same kind as that for the composition of the common metallic oxides; and the principles of their decom position are precisely similar, the inflammable matters in all ~cases separating at the negative surface in the Voltaic cir+ cuit, and the oxygen at the positive surface. These new substances will demand names and on the: same principles as I have named the bases of the fixed alka lis, potassium and sodium, I shall venture to denominate the metals from the alkaline earths barium, strontium, calcium, and magnium ; the Jast of these words is undoubtedly ob- jectionable, hut magnesium* has been already applied to metallic manganese, and would consequently have been an equivocal term. IV. Inquiries relative to the Decomposition of Mlumine, Silex, Zircone, and Glucine. I tried the methods of electrization and combination with * Bergman. Opusc. tom. ii. p. 200. quicksilver, 204 Electrochemical Researches on quicksilver, and the commén metals, by which T had sue- ceeded in decomposing the alkaline earths, on alumine and silex.; but without gaining distinct evidences of their having undergone any ene in the processes. Obliged to seek for other means of acting upon them, it was necessary to consider minutely their rlaguue to other bodies, and to search for analogies by which the principles of research might be guided. Alumine very slowly finds its point of rest at the negative pole, in the electrical circuit ; but silex, even when diffused In its gelatinous state through water, rests ae at the negative or positive poles. From this indifference to positive and negative electrical attractions, following the general order of facies it might be inferred, that if these bodies be compounds, the electrical energies of their elements are nearly in equilibrium; and that their state is either analoyous to that of insoluble neu- tral saits, or of oxides nearly saturated with oxygen. The combinations of silex and alumine, with acids and alkalis, as well as their elecirical powers, were not incon- sistent with either of these ideas ; for m some respects they resemble in physical characters, fluete and phosphate of lime, as much as in others; they approach to the oxides of zinc and tin. On the idea that silex might be an insoluble neutrosaline compound, containing an unknown acid or earth, or both, and capable of being resolved into its secondary elements, in the same manner as sulphate of barytes, or fluate of lime, I” made the following experiments : Two gold cones*, connected hy moistened amianthus, were filled with pure water, and placed in the electrical cir- cuit, a small quantity of carefully prepared and well washed silex was introduced into the positive cone: the action was kept up from a battery of two hundred plates, for some hours, till nearly half of the fluid in each cone was exhaust- ed ; the remainders were examined ; the fluid in the cone containing the silex was strongly acid ; that in the opposite * The same as those described in Phil. Trans. 1807, p. 6. —See Phil. ses vol, xxviii. p. 5 ; cone the Decomposition of the Earths, &&c. — 205 cone was strongly alkaline; the two fluids were passed - through. bibulous paper, and mixed together, when a pre- cipitate fell down, which proved to be silex. On the first view of the subject, it appeared probable that this silex had been formed by the union of ‘the acid and the alkaline matter in the two cones, and that the experiment demonstrated a decomposition and recomposition of silex ; but before such a conclusion could be made, many points were to he determined. It was possible that the acid might be nitric acid, pro- duced as in other electrical experiments of a similar nature, and that this acid might have dissolved silex, which was precipitated by the alkaline matter at the other pole, which might be either potash used for dissolving the silex, which had adhered to it, notwithstanding the processes of lixivia- tion in acids, or ammonia produced in consequence of the presence of the atmosphere ; or if potash was present, it was likewise possible that the silex might have been carried over in solution, with this alkali, from the positive to the nega- tive surface. Minute experiments were instituted and completed in the same manner as those detailed in the Philosophical Trans- actions for 1807, p. 7 *, which soon proved that there was no reason to suppose that the silex had been changed in these experiments. The acid proved to be nitric acid, which under the elec- trical action seemed to have dissolved the silex; the alkali turned out to be principally fixed alkali; and that it was merely an accidental ingredient, and not a constituent of the silex, appeared from this circumstance, that when. the game portion of silex was long electrified, by degrees it lost its power of affording the substance in question f This * Phil. Mag. vol. xxviil. p. 6. + If silex that has been carefully washed, after precipitation by muriatic acid from liquor silicum, be moistened, and acted on by mercury negatively electrified, the mercury soon contains a notable quantity of potassium. Well washed alumine that has been precipitated from alum by carbonate of soda, affords by the same treatment sodium and potassium, so that the powers of electrochemical analysis are continually demonstrating the imperfection of the common chemical methods of separating bodies from each ‘other. The purest 206 Electrochemical Researches on This result having taken place, the same plan of operation was not pursued with respect to alumine, which resembles a saline compound less than silex, and the method which I now adopted of acting upon these bodies, was on the sup- position of their being inflammable substances so highly saturated with oxygen as to possess little or no positive elee- tricity. Alumine and silex have both a strong affinity for potash and soda: now supposing them to be oxides, it was reason- able to conclude that the oxygen, both in the alkalis and the earths, must be passive as to this power, which must consequently be referred to their bases, and on this notion it was possible that it might be made to assist their decom- position by electricity. After this reasoning, I fused a mixture of one part of si- Jex, and six of potash in a platina crucible, and preserved the mixture fluid, and in ignition, ‘over a fire of charcoal ; the crucible was rendered positive from the battery of five hundred, and arod of platina, rendered negative, was brought in contact with the alkaline menstruum. At the moment of contact there was a most intense light; when the rod was- plunged into the liquid an beuivebeanae took place, and globules which burnt with a brilliant flame rose to the sur- face, and swam upon it in astate of combustion. Ina few minutes, when the mixture was cool, the platina bar was removed: after as much as possible of the alkali and-silex had been detached from it by a knife, there remained bril+ liant metallic scales round it, which instantly became cover- ed with a white crust in the air, and some of which in+ flamed spontaneously. The platina appeared much cor roded, and of a darker tint than belongs to the pure metal. When it was plunged into water it strongly effervesced :, the fluid that came from it was alkaline; when a few drops of muriatic acid were added to the Beye a white cloudi- paurest boracic acid which can be obtained from borax by chemical decompo- sition, by electrical analysis is shown to. contain both soda, and the decom- posing acid employed in the process; and hence the experiment on the action | ef the beracic acid and potassium, page 201, nd possibly be staan grighous assuming its decomposition. ness the Decomposition of the Earths, &c. 207 ‘ness occurred, which various trials demonstrated, Bopended upon the presence of silex. A similar mixture of potash and alumine was expert- mented upon in the same manner, and the results were per- fectly analogous; there adhered to the rod of platina a film of a metallic substance, which rapidly decomposed water, and afforded a solution which deposited alumine by the ac- tion of an acid. I tried several forms of this experiment, with the hopes of being able to obtain a sufficient quantity of the metallic mat- ter from the platina, so as to examine it in a separate state ; but I was not successful. It was always in superficial scales, which oxidated, becoming white and alkaline, before it could be detached in the air; it instantly burnt when heated, and could not be fused under naphtha or ail. I tried similar experiments with mixtures of soda and alumine, and soda and zircone, and used iron as the nega- tively electrified metal. In all these cases, during the whole. process of electrization, abundance of globules, which swam in a state of inflammation on the fused mass, were produ- ced. And in the mixture, when cooled, small. lamine of metal were found of the colour of lead, and less fusible than. sodium, which adhered to the iron; they acted violently. upon water, and produced soda and a white powder, but im quantities too small to be minutely examined. I endeavoured to procure an alloy of potassium, and the: bases of the earths, from mixtures of potash, silex, and alumine, fused by electricity, and acted on by the positive and negative surfaces in the same manner as pure potash, tn experiments for the decomposition of that substance; bat I obtained no good results. When the earths were in quan- iities equal to one-fourth or one-fifth of the alkali, they rendered it so highly non-conducting, that it was not easy to effect it by electricity ; and when they were in very minute: portions, the substance produced had the characters of pure potassium. I heated simalf globules of potassium, in contact with ee and alumine, im tubes of plate glass filled with the vapour. oft naphtha: the potassium seemed to act at the same time: upon 208 _. Electrochemical Researches on upon the glass and the earths, and a grayish opaque mass not possessed of metallic splendour was obtained, which effervesced in water, depositing white clouds. Here it was possible that the potash had been converted wholly or partly into protoxide, by its action upon the earths; but as no globule was obtained, and as the plate glass alone might have produced the effect, no decided. inference of the de- composition of the earths can be drawn from the process. I shall now mention the last trials that I made with re- spect to this object. Potassium, amalgamated with about one- -third of mer-’ cury, was electrified negatively under naphtha, in contact with silex very slightly moistened, by the power of five hun- dred ; after an hour the result-was examined. The potas- sium was made to decompose water, and the alkali formed neutralized by acetous acid; a white matter, having all the appearance of silex prcaiieared: but in aca too small for accurate examination. [ tried the same inethod of action upon alumine and glu- cine, and obtained a cloudiness, more distinct than in the case of silex, by the action of an acid upon the solution ob- tained from the amalgam. Zircone exposed in the same manner to the action of elec- tricity, and the attraction of potassium, furntshed still more satisfactory results ; for a white and fine powder, soluble in sulphuric acid, and which was precipitated from sulphuric acid by ammonia, separated from the amalgam that had been obtained, by the action of water. aft From the general tenor of these results, and the compari- son between the different series of experiments, there seems. very great reason to conclude that alumine, zircone, glu- ‘cine, and silex are, like the alkaline earths, metallic oxides, for on no other supposition is it easy ro explain the pheno-: mena that have been detailed. . : 0 The evidences of decomposition and composition are* not, however, of the same strict nature as those that belong to. the fixed alkalis and alkaline earths ; for it is possible, that in the experiments in which the niles alumine, and zitcones: appeared to separate during the oxidation of potassium and: sodium, ‘ the Decomposition of the Earths, €c. 209 sodium, their bases might not actually have been im com- bination with them, but the earths themselves, in ~union with the metals of the alkalis, or in mere mechanical mix- ture. And out of an immense number of experiments which I made of the kind last detailed, a very few only gave distinct indications of the production of any earthy matter; and in cases when earthy matter did appear, the quantity was such as rendered it impossible to decide on the species. o Had I been so fortunate as to Hee obtained n more certain evidences on this subject, and to have procured the metal- lic substances I was in search of, I should have’ proposed for them the names of silictum, alumium, zirconium, and glucium. ie Bear V. On the Production of an Amalgam from Ammonia, and . on tts Nature and Properties. | In the communication from Professor Berzelius and Dr. Pontin, which I have already referred to, a-most curious and important experiment on the deoxidation and amaleamation of the compound basis of ammonia ts mentioned, which these - ingenious gentlemen regard asa strict proof of the idea I had formed of its being an oxide wally binary basis. 7 Mercury, negatively electrified in the Voltaic circuit, 13 placed in contact with solution of ammonia. Under this agency it gradually increases in volume, and, when expanded to four or five times its former dimensions, becomes a soft, solid. _- And that this substance is composed of the deoxygenated compound basis of ammonia and mercury, they think is proved : First, By vhe reproduction of quicksilver and ammo-= nia, with the absorption of oxygen, when it is exposed to air ; and, Secondly, by its forming ammonia in water, whilst hydrogen is evolved, and the quicksilver ¢ cradually becomes free. An operation, in which hydrogen and nitrogen exhibit me- tallic properties, or in which a “metallic substance i Is appa- rently composed from its elements, cannot fail to fix the at- tention of chemists: and the peculiar interest which it of+ Vol. 32. No. 127. Dec. 1808. © O “fered va \ 210° Electrochemical Researches on met fered in its relations to the general theory: of electrochemiea? science, induced me to examine the circumstances connected with it minutely and extensively. ' Tn repeating the process of the Swedish chemists, I found: -that to form an amalgam from fifty or sixty grams of mer- cury, in contact with saturated solution of ammonia, required > ' @ considerable time, and that this auralgany 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 wuder which it could be more distinetly analysed. The experiments which I have detailed in the Bakerian lecture for 1806, proved that ammonia is disengaged from the ammoniacal salts, at’the negative surface in the Voltaic circuit; aud I concluded that under this agency, it mav be acted on in what Is called the nascent state, when it was rea~ sonable to conclude it would be more readily deoxygenated and combined with quicksilver. On this view of the subject, I made a cavity ina piece of nturiate of ammonia ; into this a globule of mercury, weigh- ing about fifty grains, was tuiredeced! The mutate was slightly moistened, so as to be rendered a conductor, 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 aetion of the quicksilver on the salt was immediate; a strong effer- veseence with much heat took place. The slob it & few minutes had enlarged to five times its former dimen- sions, and had the appearance of an amaloam of zinc ;— and metallic erystallizations shot from it, as a centre, veiapid the body of the salt. They had an arborescent appearance; often became coloured at their points of contact with the - muriate ; and when the connection was broken, rapidly dis- appeared, emilting ammoniacal fumes, and reprodueing quicksilver. When a piece of moistened carbonate of ammonia was used, the appearances were the same, and’ the amalgam, was formed the Decomposition of the Earths, &c. 211 formed with equal rapidity. In this process of deoxida- tion, when the battery was in powerful action, a black matter formed in the cavity, which there is every reason to believe was carbonaceous matter from the decomposition of the car- bonic acid of the carbonate *. — The strong attraction of potassium, sodium, and the me- tals of the alkaline earths for oxyen, mmduced me to examine whether their deoxidating powers could not be made to produce the effect of the amalgamation of ammonia, inde- pendently 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 moisten= ed muriate of ammonia, the amalgam rapidly increased to six or seyen times its volume, and the compound seemed to con- tain much more ammoniacal basis than that procured by elec- - trical powers. As in these cases, however, a portion of the metal used for the deoxidation always remained in union in the com- pound ; in describing the properties of the amalgam. from ammonia, I shall speak only of that procured by electrical means. | The amalgam from ammonia, when formed at the tem- perature of 70° or SO, isa soft solid, of the consistence of butter; at the freezing temperature it becomes firmer, and @ erystallized mass, in which small facets appear, ‘but having no perfectly defined form +. Its specific gravity is below 3, water being one. When exposed to air itsoon becomes covered wil awhite — erust, which proves to be carbonate of ammonia. When thrown into water it produces a quantity of hy- drogen, equal to about halt its bulk, and in consequence * The black matter which separates at the negative surface in the electri- eal experiments on the decomposition of potash or soda, and which some experimenters have found it difficult to account for, is, I find, carbonaceous, and depéadent upon the presence of carbonic acid in the alkali. + From thie: facet I suspect the form to be cubical. The amaigam of po- tassium crystallizes im cubes as beautiful, and in some cases as large, as ; those ef bismsth. O 2 of $12 Electrochemical Researches on of this action the water becomes a weak solution of am monia, Me When it is pines: in a given portion of air, the air en- larges considerably m sae: and the pure quicksilver re- appears. Ammioniacal gas, equal to one and a half or oné and three-fifths of the’ volume of the amalgam, ts found to be produced, and a quantity of oxygen equal to one-seventh or one-eighth of the ammonia disappears *. When thrown into muriatic acid gas, it instantly becomes coated with muriate of ammonia, and a small quantity of hydrogen is disengaged. In sulphuric acid it becomes-coated with sulphate of am- monia and sulpbur. - ; I attempted by a variety of modes to preserve this amal- _gam. I had hoped by submitting it to distillation out of the contact of air, or water, or bodies which could furnish oxy- gen, to be able to obtain the deoxygenated substance which had been united to the quicksilver in a pure form; but all the circumstances of the experiment opposed themselves to such a result. It is well known to persons accustomed to barométrical 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 continually 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 ; [ 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. u * This experiment confirms the opinions I have stated concerning the quan- tity of oxygen in ammonia; but .a9 water is present, as will be immediately skown, the data for proportions are not perfectly correct. The 4 Sal the Decomposition of the Earths, Sc. =. OS 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 51, part of a grain, “and to supply oxygen to this scarcely soso part of agrain 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, whey an amalgam, which had been wiped by means ef bibulous paper, was introduced into naphtha, it decom- posed almost as rapidly as in the air, producing ammonia and hydrogen. In oils if evolved hydrogen, amd generated ammoniacal soap; and when it was introduced inio a glass tube, closed by a cork, gas was rapidly formed, and the mercury remain- ed free; and this gas, when examined, was found to consist of from about two-thirds to three-fourths ammonia, and the — remainder hydrogen *. That more moisture sometimes existed attached to the amalgam, when wiped as dry as possible by bibulows paper, than was sufficient forthe 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 sniall tube :’ in this tube it was heated til] the gaseous matter had expelled the quicksilver; the tube was, then closed, and suffered to cool, when moisture, which proved to be a saturated solution | of ammonia, bad precipitated upon it. _ Thave mentioned that the amaigams obtained fram am- monia, by means of the metals of the fixed alkalis or alka- Jine earths, seemed to contain much more ammoniacal basis in combination than those procured by electricity sand when they are combined with the metals of the fixed alkalis or of the earths in any considerable quantities, they are much more permanent, i Triple compounds of this kind, when carefully wiped, acarcely produce any ammonia under naphtha, or oil, and * In the experiment of the action of the amalgam upon air, the oxygen is probably absorbed by nascent hydrogen, and. reproduces water, which is dis- golved by the ammonia. p O03 may \ 214 Electrochemical Researches on ‘ may be preserved for a considerable time in closed glass tubes, a little hydrogen being the only product evolved trom them. v I heated a triple amalgam iid from ammonia by 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 mate. ter was emitted, but the heat was raised till gas was rapid- ly 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 mer- cury had absorbed in cooling. The small quantity which was permanent, did nat equal one half the volume of the amalgam. ' On the idea that this gas might be a compound of hydro- gen and nitrogen in the state of deoxygenation, I mixed a small quantity of oxygen 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 oxygen that had been introduced, and of hydrogen and nitrogen to each other in the proportion of nearly four to one. At first I was perplexed by this result, which seemed ta prove: the production of ammonia, independent of the pre- sence of any substance which could furnish oxygen to it, and to show that its amalgamation was merely owing to its being freed from water, and combined with hydrogen ; but a satisfactory solution of the difficulty soon offered itself. Exposing the triple amalgam procured from ammonia by potassium to a concentrated solution of ammonia, I found > that it had very little action upon it, and introducing the amalgam moistened hy it into a glass tube, it had nearly the same permanency as the amalgam which had been wiped before it was introduced, a litile hydrogen only being eyolved ; but on heating the tube gaseous matter was rapidly gene- rated, which proved to consist of two-thirds ammonia, and one-third hydragen. - Nias got , In the Decompositron of the Earths, 8c. 215 _ Yn the instance in which the amalgain had been wiped, a small quantity of solution of ammonia, and perhaps of potashy must have adhered to it; and though the amalgam does not act upon this powerfully at common temperatures, yet when the water ts ratsed in vapour, it tends to oxygenate both the basis of ammonia and potassium, and hence hia ae 48 evolved, and volatile alkali preduced. ; I distilled an amalgam procured by potassium from afns monia, ina tube filled with the vapour of naphtha; and hert- mietically sealed, in the same manner as in the expérithents for obtaining the metals of the earths; but in this case I pro+ cured ammonia, hydrogen, and nitrogen only, and puré mer- cury; and the residuum was potassium, which acted powers fully on the glass tube. In another experiment of the same kind, I kept one part of the tube cool by ice, at the time the other part was strongly heated, but nothing condensable except mereury was pro- duced, and the elastic products were the sainé as in the former instance. ; I endeavoured to procure an amalgam from ammonia, t6 which no moisture could be supposed to adhere, by heating an amalgam of potassiutm in ammoniacal gas. “The amial- gam hecame cevered with a film of potash, but it did not enlarge in its dimensions, and a considerable quantity of non-absorbable gas, which was found to consist of five parts of hydrogen and one of nitrogen, was produced. The amnal- gam after this operation did not emit amimonia by exposure to air ; hence it seems probable, that for the deoxygena- tion of ammonia, and the combination of its basis with mers cury, the alkali must be in the nascent state, or at least in that condensed form in which it exists in ammoniacal salts, - Or solutions. VI. Some Considerations of general Theory, connected with thé Metallization of the Atkalis and the Earths. The more the properties of the amalgam obtained from ammonia are considered, the more extraordinary do they appear. Mercury by combination with about +>4o5 part of its O04 weight £16 Electrochemical Researches on ‘ 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 con- ducting powers remaining unimpaired. . : ~Itis “scarcely possible to conceive that a substance which fornis with mercury so perfect an amalgam, should not be metallic in its own nature*; and on this idea, to assist the discussion concerning it, it may be conveniently termed am- monium. But on what do the metallic properties of ammonium de- pend? Are hydrogen and nitrogen hoth metals in the aériform state, at the usual temperatures of the atmosphere, bodies of ihe same character, as zinc and quicksilver would be in the, heat of ignition? ae -Or are these gases, in their common form, oxides, which become metallized by deoxidation ? Or are the simple bodies not metallic in their own nature, but capable of composing a metal in their deoxygenated, and an alkali in their,oxygenated state ? These. problems, the second of which was stated by Mr. Ca- vendish tame, and the last of which belongs to Mr. Berzelius, offer most important, objects of investigation. I haye made some experiments in relation to them, buf as t unsuccessfully. I have heated the amalgam of potas- ;... in contact with both hydrogen and nitrogen, but with- out attaining. their metallization ; but this fact cannot be considerered as decisiyely for or against any one of these ¢on- jectures. I mentioned in the Bakerian lecture for 1807, that a mo- ; * The nature of the compounds of sulphur and phosphorus with mercury favours this opinion ; these inflammable bodies by combination impajr its, metallic properties ; ; cinnabar i is anon-conductor, and jt would seem from Pelletier’s experiments, Ann, de Chimie, vol. xiii, p. 125, that the phosphuret of mercury is not ‘metallic i in its characters; charcoal is a conductor, and i in plumbago carbon approaches very near to a metal in its characters, so that the metallic nature of steel does not militate against the reasoning in the text, The only facts which I am acquainted with, that do militate against it, are the metallic characters of some of the sulphurets and phosphurets of the impers fect metals. ee dification \ the Decomposition of the Earths, &c. OF dification of a phlogistic chemical theory might be defended on the idea that the metals and inflammable solids, usually - called simple, were compounds of the same matter as that existing in hydrogen, with peculiar unknown bases, and that the oxides, alkalis, and acids were compounds of the same bases with water, and that the phenomena presented by the metals of the fixed alkalis might be explained on this hypo- thesis. ; The same mode of reasoning may be applied to the facts of the metallization of the earths and ammonia, and perhaps with rather stronger evidences in its favour, but still it will be less distinct and simple, than the usually received theory of oxygenation, which I have applied to them. The general facts of the combustion, and of the action of these new combustible substances upon water, are certainly most easily explained on the hypothesis of Lavoisier; and the only good arguments in favour of a common principle of in- flammability, flow from some of the novel analogies in elec- trochemical science. Assuming the existence of hydrogen in the amalgam of ammonium, its presence in one metallic compound evidently leads to the suspicion of its combination in others. And in the electrical powers of the different species of matter, there are circumstances which extend the idea to combustible sub- Stances in general. Oxygen is the only body which can be supposed to be elementary, attracted by the positive surmee 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 oxygen. Hydrogen is the-only matter attracted by the negative surface, which can be con- sidered as acting the opposite part to oxygen: May not then the different inflammable bo‘ies, supposed to be simple, con- tain this as a common element ? ; Should future experiments prove the truth of this hypo- thesis, still the alkalis, the earths, and the metallic oxides will belong to the same class of bodies. From platina to potassium there is a regular order of gradation as to thei: physical and chemical properties, and this would probably extend to ammonium, couid it be obtained in the fixed form. Platma 218 Electrochemical Researches on 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 strentium. The phe- momena of combustion of all the oxidable metals are pre- cisely analogous. In the same manner as arsenic forms an acid by burning in air, potassium forms an alkali and cal- cium an earth 5 i ia manner similar to that in which osmium forms a volatile and acrid substance by the absorption of oxygen, docs the amalgam of ammonium produce the vola- ule alkah; and if we suppose that ammonia is metallized, by being combined with hydrogen and freed from water, the same reasoning will likewise apply to the. other metals, with this difference, that the adherence of their phlogiston or hydrogen would be exactly in the inverse ratio of their attraction for oxygen. In platina¥ it would be combined with the greatest energy ; in ammonium with the least 5 and if it be separable from any of the metals without the aid of a new combination, we may expect that this result will be af- forded 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 pressure of the at+ mosphere removed. Whatever new lights new discoveries may throw upon this subject, still the facts that have been advanced, show that a step nearer at least has been attained towards the true kwowledge of the nature of the alkalis and the earths . Something * The common metallic oxidesare lighter than their bases, but petash and soda are heavier ; this fact may be explained oneither theory; the density of 2 compound will be proportional to the attraction of its parts. Platina, having a weak affinity for oxygen, cannot be supposed to condense it in the same degree a3 potassium dees; or if platina and potassium be beth corm- pounds of hydrogen, the hydrogen 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 oxygen strong ; and in a.case when the metal is much lighter and the attraction for oxygen stronger, it might be expected a priori that the exide would be heavier than the base. + Since the: facts in vii paper were communicated to the Royal Society, Ihave + the Decomposition of the Earths, &c. 19 . \ ° Something has been separated from them which adds to their weight ; and whether it be considered as oxygen, or as water, have seen an account of some very curious experiments of M.M. Gay Lus- sac and Thenard, (in number 148 of the Monteur, for 1808, which I have just received,) from one of which they have concluded, “ that potassium may be a compound of hydrogen‘and potash.” - These gentlemen are said to have heated potassium in ammonia, and found _ that the ammonia was absorbed, and that hydrogen gaa equal to two-thirds of its volume appeared, and that the potassium by this process had become of a grayish-green colour. By heating this grayish-green substance consider- ably, two-fifths of the ammonia were again emitted, with a quantity of hydro- gen and nitrogen corresponding to one-fifth more; and by adding water to the mixture, and heating it very stronglyagain, they obtained the remainder of the ammonia, and nothing but potash was left. In these complex processes, the phenomena may be as easily explained on the idea of potassium being a simple, as that of its being a compound, sub- stance; 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 che- mists, as detailed in the notice referred to, be at all admitted. Potash, as I have found by numerous experiments, has no affinity for am- ntonia, for it does not absorb it when heated in it; it is net therefore (allow- ing their theory) possible to conccive that a substance having ne attraction for potash, should repel from it a substance which is intimately combined with it, and which can be separated in no other way. A part of the hydrogen evolved in their experiment, may be furnished by water contained in the ammonia; but it is scarcely possible that the whole of it can be derived from this source, for on such an idea the ammonia must con- rain more than half its weight of water. There is however no evidence that the whole of the hydrogen may not be furnished by the decomposition, of the volatile alkali itself. Potassium in its first degree of oxygenation may have an affinity for nitrogen, or potassium may expel a portion of hydrogex at the moment of its combination with ammonium; and as the whole of the am- monia cannot be regenerated without the presence of water, hydrogen and 2 little oxygen may be furnished to the remaining elements of the ammonia, from the water, and oxygen to the potassium. Even before the conclusion was formed, that a metallic substance is decom- posed in this experiment, it should have been proved that the nitrogen had not been altered. That mere potash, combined with hydrogen, cannot form potassium, is, { think, shown by anexperiment which I tried, in consequence of the important fact lately ascertained by M. M. Gay Lussae and Vhenard, of the deoxidation of potash by iron. “An ounce of potash was kept in ignition for some time in an iron tube, ground into a gun barrel in which one ounce anda half of iron turnings were ignited to whiteness ; a communication was opened, by withdrawing a ; wire 2 / _ 920 . Electrochemical Researches on « water, the inflammable body is less compounded than the uninflammabie substance resulting from its combustion. Ser 6 wire which closed the cue containing the potash, between that alkali and the metal. i As the potash came in contact with the iron, gaseous matter was developed, which was received in a proper apparatus, and though some of it was lost by passing through the potash into the atmosphere, yet nearly half a cubic foot: - was prescrved, which proved to be hydrogen. In the tube were found two products, one in the quantity of a few grains, containing potassium, combined - with a small quantity ofiron, and which had sublimed in the operation, and the other, a fixed white metallic substance which consisted of an alloy of iron and potassium. The first of these substances burnt when thrown upon water; 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 ale kali; but on M. M. Gay Lussac’s and ‘Thenard’s theory, this potash must contain water, not only sufficient to furnish hydrogen to metallize the-alka- li, but likewise the quantity disengaged : dry potash, then, as it is procured in our experiments, must on this theory be a compound, containing.a cons siderable quantity of matter which can furnish hydrogen ; ; and what would be its form or properties if deprived of this matier we are wholly uns able to judge, which brings this question to the general question discussed in the text. Potassium I find may be Lae readily from dry ignited potash in elecs trical ope nen ; and the result of the combustion of potassium in oxygen 5 gas is an alkali, so dry that it produces violent heat, and ebullition when water is adGed to it. Tn M. M. Gay Lussac’s and Thenard’s experiment on the action of potas- sium on ammonia, the hy drogen disengaged i in the first process, and that ex- isting in the ammonia disengag red in the second process, exactly equals the whole quantity contained in the ammonia. But there is no proof of any hy- drogen being disengaged from the potassium, for the ammonia lost is not ge- nerated, nor potash formed, but by the addition of a substance, consisting of oxygen and hydrogen; and as the three bodies_concerned in this experiment are potassium, ammonia, and water, the result ough¢ to be potash, ammoiuja, and a quantity of hydrogen, equal to that evolved by the mere action of water on potassium, whichis said to be the case. Even ifthere were no other proofs, the chemical properties of potassium are sowholly unlike chose that might be expected trom a compound of potash and hydrogen, that they are almost sufficient to decide the question. Potas- sium acts bpon water with much more energy than potash,and produces much more heat im it, and yet if 2 compound of hydrogen, theafMinity of potash for water must be diminished by its affinity for hydrogen, to say nothing of the quantity © the Decomposition of the Earths, &c. 291 Other hypotheses might be formed upen the new electra- chemical facts, in which still fewer elements than those al- lowed in the antiphlogistic or phlogistic theory might be maintained, Certain electrical states always coincide with certain chemical states of bodies. Thus acids are uniformly negative, alkalis positive, and inflammable substances high- ly positive ; and, as I have found, acid matters when posi-_ tively electrified, and alkaline matters when negatively electrified, seem to lose all their peculiar properties and powers of combination. In these instances the chemical qualities are shown to depend upon the electrical powers ; and it is not impossible that matter of the same kind, pos- sessed of different electrical powers, may exhibit different chemical forms * @ T ven- quantity of heat, which ought (on the common theory of capacity for heat) to be carried off by this light inflammable gas. Potassium burns in carbonic acid, and precipitates charcoal from it ; whereas hydrogenelectrized with carbonic acid, converts it into gaseous ous ef carbon. Potash has a very slight attraction for phosphorus ; but La cei has 2 very strong affinity for it, so as to separate it from hydrogen, and according to M. M. Gay Lussac and Thenard, with the phanomena of inflammation. Potash has no affinity for arsenic, yet from thé experimentsof these gentlemen, it appears that potassium separates arsenic from arseniated hydrogen; and hydrogen, which is supposed by them to exist in both compounds, can have “no affinity for hydrogen,nor can hydrogen in one form, be supposed capable ef separating arsenic from hydrogen in another form. Could not the experiment of M.M.Gay Lussac and Thenard he explained, except on the supposition of the hydrogen being derived from the pota:sium, 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 hydrogen and potash, but that it is composed of hydrogen anda” unknown a and that potash is this basis united to water. * Philosophical Transactions, 1807. Part I. p. 23. The amalgam obtained from ammonia offers difficulties to both the phlogistic and antiphlogistic hy- potheses. If we assume the phlogistic hypothesis, then we must assume tha nitrogen, by combining with one-fourth of its weight of hydroven, can form an alkali, and by combining with one-twelfth more, can become metallic. If we reason on the antiphlogistic hypothesis, we must assert, that though ni- trogen has a weaker affinity for oxygen than hydrogen, yet a compound of hydrogen and nitrogen ts capable of decomposing water. ; The first assumption is however by far the most contradictory to the order ef common chemical facts: the last, though it cannot be whelly removed, is yet lessened by analogies. Thus alloys iu general, and inflammable compounds, ate \ £29 Electrochemical Researches, Be. I venture to hint at these notions: but I do not attach much importance to them; the age of chemistry 1s not yet sufficiently mature for such discussions ; the more subtilé powers of matter are but just beginning to be considered ; and all general views concerning them must as yet rést upon feeble and imperfect foretold: Whatever be the fate of the speculative part of the inquiry, the facts however will, I hope, admit of many applications, and explain some phenomena in nature. The metals of the earths cannot exist at the surface of the globe, but it is very possible that they may form a part of the interior; and such an assumption would offer a theory for the phenomena of voleanos, the formation of lavas, and the. excitement and effects of subterrancous heat *, and would probably lead to a general hypothesis in geology. are more oxidable than the simple substances that compose them. Sulphuret of iron at common temperatures decomposes water with facility, whereas sul- phur under the same circumstances, has no acticn on water, and iron a very- small one. ‘The compound of phosphorus and hydrogen is more inflammable, than either of its constituents. Should a new theory of the dependence of the chemical forms of matter upon electrical powers be established, the facts belonging toammonium would , admit of a more easy solution. Ammonium might be supposed to be a simple bady, which by combining with different quantities of water, and in different states of electricity, formed nitrogen, ammonia, atmospherical air, nitrous . oxide, nitrous gas, and nitric acid. Water, on this idea, must be supposed,a constituent part of all the different gases; but its electricities in oxygen and hydrogen would probably be the very reverse of what they have been supposed by M. Ritter, and, some inges nious English inquirers. Water positively electrified would be hydrogen, water negatively electri+ fied, oxygen ; and as in the yey ysical experiments of temperature, ice, added: to certain quantities of steam “y an equilibrium of heat produces water,-so in the ehiemical experiment of the generation of water the positive and nega- tive electricity of oxygen and hydrogen in certain proportions would annihi-: late each other, and water alone be the result. At all events ammonium, whether simple or compound, must be considered as owing its attraction for oxygen to its highly positive electrical state, which is shown by its de he determination to the negative surface in the Voltaic circuit. * Let it be assumed that the metals of the earths and alkalis, in alloy with: common metals, exist in large quantities beneath the surface, then their ac cidental exposure to the action of air and water must produce the effect of subterranean fire, and a product of earthy and stony matter analogous tor lavas: The Inquiry into the Structure of Seeds. 293 _ The luminous appearance of those meteors connected with the fall of stones, is one of the extraordinary circumstances of these wonderful phzenomena. This effect may be ac- counted for, by supposimg that the substances which fall, come into our atmosphere im a metallic state; and that the earths they principally consist of are a result of combustion ; but this idea has not the slightest connection with their om- gin or causes. sae ee ——— = SR RT SETI I A CTT COS TL OTL XXXIV. An Inquiry into the. Structure of Seeds, and espe- cially into the true Nature of that Part called by Geertner the Vitellus. By JaMrs Epwanp Smira, M.D. F.RS, PALS.* Grea so justly celebrated for his anatomical and phy- siological inquiries into the nature of seeds in general, and for his particular illustration of one thousand different kinds, ‘¢laims the merit of first giving a name and definition to a part called by him the Vztellus, which, though not entirely unobserved by preceding philosophers, had received no par- ticular description nor explanation. Before we enter upor the investigation of this organ, it is necessary to, consider: 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, — raoisture, heat, and air. A seed committed to the ground absorbs, through the vessels of its base, the juices of the 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 - heat, however, are not of themselves sufficient to cause the germination of seeds. It has long been. known that, air is equally necessary ; and modera chemists have ascertained. oxygen gas tobe the particular ingredient of the atmospheric air which ts requisite, and which is absorbed. by seeds, in, * From Linnwzan Tragsaecions, vol. ix. p. 204 the : (é z - 224 Inquiry into the Structure of Seeds. the moments.of incipient germination, from or through the surrounding soil: Thus the bulk of the seed is increasedy and its vital principle stimulated. It bursts its immediate integument, or festa, and in the first place sends forth the radicle, or young foot, into the ground. ‘This part being, as Dr. Darwin well observes, most susceptible of the. sti- mulus of moisture, elongates itself in the direction in which it meets with that stimulus ; ; and descending into the earth, while it fixes the infant plant, assumes its own proper func- tion of imbibing nourishment for the future support of that plant. But before any supplies can he thus obtained, con- siderable demands are made, even by the root itself; _and not only an evolution of parts, but lkewise an increase of bulk, takes place in the young vegetable. For this neces- sary purpose a store is prepared in the allwmen, a sub- stance 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 oxygen, into amilky or saccharine Huid; or the same substance is lodged in, or united with, the bulk of another part, next to be mentioned, the cotyledon, or, as they are generally of the plural number, cotyledons. As the root is the part stimu- lated by moisture, the cotyledons appear to be mest stimu- lated by air, and they consequently raise themselves, for the - most part, out of the ground in order to receive it, im the form of seminal Jeaves well known to perform, for atime, the functions of real leaves, and even, by the action of light, to assume their green colour. The allumen cannot be said to be stimulated, or acted upon as a living body, hy the air or gas, which only produces chemical changes in it ; and the destination of this substance being soon accom- plished, it disappears by absorption. 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 ascending plant, which last originates from the extremity 7 the embryo oppesite to the root, but always, like that, most intimately connected with’ the cotyledons.. These indeed, sooner or later, wither away ; when the ac- quisition of real and more ample foliage renders them super- fluous, \ Inguiry intd the Structure of Seeds. 295 uous; or no longer necessary. But all coryledons do.not ascend out of the earth, nor assume any of those functions of leaves in which light is concerned. In the borse chesnut, ahe cyamus nelumbo, the tropeolum 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, papilionacece, some, as lwpinus, raise their cotyledons into the air and light, in the form.-of very conspicuous green seed-leaves;-while others, as dathyrus, 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 knowa farmaceous allumen is lodged, whether they rise into the light or not; and the closest analogy leads us to conclude that their functions are otherwise similar, which can only be with respect to air. Even cotyledons however are not indispensably requisite to a seed, though the albumen ap- pears to be, in some form or other, necessary to all seeds. Not to mention the tribes of vegetables allowed. or guessed -to be without cotyledons, and thence, for systematical con- venience, denominated acotyledonous; all, who have suff- ficiently considered the matter, know that in those» called monocotyledonous, what is vulgarly taken for the cotyledon is really an albumen, a part fundamentally distinct.in func- tions from what is proper toa cotyledon. Thus even so conspicuous a family of plants ias the orchidee, which the faithful Jussieu confesses were only presumed from analogy 4o be monucotyledonous, or, as he guardedly expresses it, to have §* a single-lobed corculum,’’ have been shown by Mr. Salisbury, in the 8th volume of cur Transactions, the only person I believe who has well. examined their germination, to have in fact an albumen, but no; cotylédon at all. “Nar does such ambiguity or uncertainty belong: to,this family alone. Many plants are presumed to be: monocotyledonous, chiefly because they grow. in the water; and.itas much ta be regretted that this fundamental principle ofuall ‘natural systems should in many cases be so ill-established, and very often so extremely dificult to detect or to determine ; whick happens in general where its help is most wanted, as I shall Vol, 32. No. 127. Dec. 1808. Be presently £26 Inquiry into the Structure of Seeds. presently endeavour to show; but I must first speak of “bd more immediate object of the present essays) 1.99% ‘Geertner asserts the vitellus of seeds to be ¢ distinct fic 3 the cotyledons as well as from the albumen, and, for the most part, situated between the latter and the embryo.” He considers as its principal diagnostics the three following characters: ** 1st, That it is most closely connected with the embryo, so as not to be separable from it without injury to its own substance: 2dly, That notwithstanding this intimate connection, it never rises out of the integuments of the seed, as the cotyledons usually do, in germination, so as to be- come a seminal leaf, but, rather like the albumen, 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 vztedlus is always situated betwixt that and the embryo, in such a manner, however, that. it may be separated from the albumen with great ‘ease and without injury.” For which reasons this able writer con- siders the organ in question as ¢¢ allied on the one hand to the: albumen, on the other to the cotyledons,” but’ truly distinct in nature from both. He proceeds to observe that ‘< it is of all the internal parts of a seed the most ee and by far the most unfrequent.” Now, to consider: all these points separately, in the }st place, The vitellus is not more closely connected with the embryo than the greater part of cotyledons are; according to the figures and descriptions of Gertner himself, the fi- delity 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 conneciion of the parts.is best ascer- tained. @dly, That the vitellus never rises out of the ground, is a circumstance common to it with many cotyledons, al- lowed to be such by Gertmer, as in the leruminous plants, and others already mentioned. 3dly, That the vitéllus is situated between.the albumen (if the latter be present ‘as a oe organ) and the wid is only a necessary con- x : : Sonne Inquiry inte the Structure of Seeds. 227 Sequence 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. For these reasons I presume the vitellus to differ in no respect from the subterraneous cotyledons al- ready described ; and that its office is to perform the neces- sary functions relative to air or oxygen,’ till the leaves come forth and assume those functions, in greatei-perfection, with the cooperation of light. This seems more satisfactory than the opinion of Geriner, that the organ underconsi- deration affords nourishment to the embryo ; because this is abundantly supplied by the copious aljumen of a multi- tude of seeds whose wited/us is very inconsiderabie, as grasses , and because it is unphilosophical to recur to two causes, when one 1s evidently sufficient. In fact, the vitellus, .as far -as I can observe, only dwindles away when the leaves un- fold, exactly as happens to the subterraneous cotyledons. The same thing very often takes place as speedily in those which rise out of the ground ; the existence of the latter ap- pearing io be prolonged in some instances, merely by their nearer approach to the nature of leaves, as in umbelliferous and cruciform plants. The difference of duration, is still - more evident, and more instructive as to our present pur- pose, in the leguminous family, between such cotyledons as rise above the ground, like Jupines, and those which remain buried, like vetches, the latter decaying as quickly as any supposed vitellus can-do, In grasses the scale, taken by Geertner for a vitel/us, is mostly so thin and unsubstantial, as not possibly to contain any material portion of nourish- ment; but its expanded figure is very well calculated, like that of the leaves, for functions analogous to vegetable respi- . ration, and its whole aspect conveys the idea of a. primary _- or subterraneous leaf, quickly rendered superfluous by the | production of real Igaves, which, as well as the radicle, are probably, in th¢ 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 orchidee prove to be destitute of it. On the other hand, | can find. : P@ com no ’ ‘ 208 Inquiry into the Structure of Seeds. no instance ofa supposed witellus, and a real cotyledon or cotyledons, in the samie plant. What ‘Gertner terms the cotyledons of rhizophora, | in his tab. 45, appears to me to be the plumula, and in his descriptions of some of the scita- minee, he evidently takes the latter for a cotyledon. By understanding, the vitellus as a cotyledon, all amii- guity respecting the component parts of any seed is removed. When the cotyledons are two or more, the only question is, whether the albuminous matter is lodged in their substance, ov 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 partial iicorporation, with the embryo, asin xamia*; whereas the pure separate albumen of the true palms has, as in every other instance, no more conection with the embryo, according to Geertner’s just remark, than is absolutely necessary 5 and moreover evinces its true nature by the chemical alterations. and speedy absorption, of its whole substance. The cotyle-. don, as I consider it, of zamza, as in numerous parallel in- stances, shrivels and shrinks indeed considerably, from the. absorption of its albuminous contents by the vegetating em=- bryo, but does not disappear, leaving only askin behind, like the albumen of grasses or corn, because 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. It may further be observed upon this subject,. that the albuminous matter of seeds with two or more co- tyledons is commonly of an oily nature, while those withs one cotyledon or none at ail, have a more farinaceous, of even stony, albumen. Sutil the latter changes to a milky or: oily fluid, previous to its absorption. When the vital prin- ciple of a seed is extinct, its albuminous oil becomes rancid), and, even in seeds that retain life, is liable to suffer some: deterioration by keeping. Hence, as Darwin observes, * Mr. R. Brown, who has fisceua the germination of a large species of. zamia in New Holland, assures me thar he found no such incorporation of; the parts in question, as Gxriner has represented in his ¢. 3, and that the: structure and evolution of every part bore an, exact resemblance to: cycas. as- described by M. Aubert du, Petit. Thoners.. 380 0) 240%” gardeners: Inguiry into the Structure of Seeds. £29 gardeners preserve melon and cucumber seeds, perhaps for years, that the plants they produce may be Jess luxuriant, in consequence of being starved at their first germination ; fort any injury to the cotyledons, even after they begin to rise above ground, is found to cramp the subsequent growth’ of the pliant. The oi! of the cotyledons has been usually sup- posed a protection to their internal parts, T presume against wet; but this purpose it by no means does or cat answer, for all seeds readily absorb moisture whenever they meet with it, and, if likewise exposed to the action of oxygen, they vegetate, in whatever situation they may otherwise happen to be. 1 suspect moreover that the oily and muct- javinous fluids of seeds ia general, before they perform their office in germination, all previously beceme milky, and often saccharine, from the actions of water and oxygen. It might be worth while to inquire, whether exposure of such seeds as are most prone to turn rancid, toa quantity of oxygen, would tend 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 13 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- laginous, or farinaceous, being, when not a distinct and separate body, always lodged in the cotyledons, throws ad- ditional light on the nature of the last-mentioned parts, and in a very beautiful manner confirms their analogy with leaves. The discoveries of Mr. Knight have proved that the nutritious 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 ao body. The chemical experiments, of Dr. Privstley P3 more 230 Inquiry into the Structure of Seeds. more especially, confirm this, by teaching us that carbonic= acid-gas is absorbed by leaves in the day-time through their upper surface, and decomposed by them, its carbon being | added to the sap, and its oxygen emitted by the under sur- face. - In the dark, leaves are found 'to absorb oxygen. Let us apply all this to ihe germination of seeds. The oxygen, known, as I have already said, to be necessary to this pros cess, bei ng conveyed to the seed in iis dark subterraneous situation, is absorbed by its cotyledons, already stored, from the copstitution of the parent plant during their formation, wit, albuminous matter abounding with’the carbonic prin- ciple. The chemical action of the oxygen on this albumi- nous substance, renders the latter a more or less saccharine, and, with the addition of the imbibed moisture, a milky fluid, fit to be transmitted, through the returning vessels of the cotyledons, into the stem of the embryo, especially as al! these important parts have already begun to swell by the absorption of moisture assisted by warmth. Hence we see why light is found hurtful to incipient germination, and why carbonic-acid-gas may be given out by seeds at that periad. We perceive also why the outside of seeds is so commonly 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 perhaps the skins of some fruits. It is, moreover, evident that all the indispensable functions of the cotyledons are best per- formed under ground, and that when they rise into the air and light, it is not till after their primary destination is ful- filled, and then because, being fundamentally of the nature of leaves, they are also capable, in most instances, of as= ‘suming their functions with respect to light. It is highly worthy of notice that, in consequence of the original posi- tion of the cotyledons in all seeds, the oxygen gas must al- ways be imbibed by their under side, that, very same part which in leaves gives out:this kind of gas during the day, and probably Beade it during, the night. It would have evinced. a strange conirariety in the constitutions of two or- gans otherwise so analogous, I mean the leaves and cotyle- dons, if the upper surface of the latier, while in the unex- panded Inquiry into the Structure of Seeds. 22) panded seed,. had been presented to receive the oxygen gas. Where there is a separate albumen, without any perceptible cotyledans, it is probable that the stalk of the embryo may answer the necessary purpose ; just as the stems of leafless plants must be presumed to perform the usual chemical, functions of leaves, though we cannot ascertain in what di- rection the different airs are imbibed or discharged, there being no decided upper or under surface in such stems, any more than in ensiform leaves. Such, however, are rare ex-_ ceptions, which if not, as yet, found to throw any new light on the subject, certainly do not overturn any important part of the above hypothesis. That some part, immediately connected with the embryo, must be stimulated in order to excite the germination of a seed, this phenomenon being ; dependent on the vital principle, is evident. I conceive that, when present, the cotyledon or cotyledons are them-. selves stimulated by the oxygen gas, or rather by the heat which chemists inform us is produced by the absorption of that gas, so as to set their fluids in motion, and thus to. propel the young root and rising plumula. But when the» cotyledons are wanting, the embryo may very, well be con- ceived capable of py iets action to imbibe for itself the juices of a distinct albumen, already become milky and sac- charine by the reception of oxygen and moisture, by which merely chemical process, asin barley, so considerable a de- gree of heat is evolved, as must very powerfully excite the vital principle-of the budding’ vegetable. In the few cases where one or more cotyledons and a distinct albumen are together 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 pro- pel their fluids into the embryo and assist germination. This opinion is the more probable, as those fluids must be sup- posed more truly of the nature of sap, and more immediately fit for the use of the infant plant, than the liquor of the al- bumen. However this may be, the existence of a cotyledon 2. P4 or ) (232 Inquiry into the Structure of Seeds. or cotylédons, together with a separate albumen, m seeds, seems to me so unusual, as not to occasion much difficulty, and | would define a cotyledon to be a vital organ, capable, as such, of being stimulated by oxygen, heat, or both, for the propulsion of its contents ;. while such an albumen is merely a repository af nutritious vegetable matter, subject. to the laws of chemistry alone, and only passively 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 advanced, return to the arrangement of plants by their co-. tyledons. Plants in general are dicotyledonous, having a pair of these organs, which commonly rise out of the ground; but if they do not, it appears, from the consideration:-of the legumixous 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 few other instances, thedifs) ference is of little or no use for systematical purposes, and of no physiological importance whatever. The cotyledons of pinus all present their backs to receive the oxygen. Some plants appear to be really furnished with one sims. ple cotyledon, as zamia, and according to Gertner’s figures and descriptions, the true scitaminee, as amomum (his xin= giber), alpinia, &c.; while canna seems to have no cotyle~ don, but only an albumen. Can this be true? and if soy, “what is the value of such a distinction in a natural, classifi- cation? The liliacee, palme, and now the orchidee, are: acknowledged tp be acotyledonous, havimg only an albumeny: while the grasses, so nearly allied to them, have one catylee don, for I presume their scale must be admitted as su¢h, Gertner’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 indivisusy expressing his idea of the simple figure appropriate to thig part in such plants, but which does not prevent its) upper, extremity being strictly analogous to the plumula of the dir cotyledones. It seems to me therefore that this learned writer # Inquiry into the Structure of Seeds. 938 is mistaken in saying the monocotyledonous plants never have any plumula.. 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 he, present. To dispute about the term is as little to the purpose as to contend that the orchzde@ have no pollen, be- cause it is not of a powdery appearance. From Mr. Lindsay’s account of the germination of ferns in our 2d volume, this family must be deemed monocotyle- donous. Their germination seems at first analogous to that. of mosses, as given by Hedwig in his Theorva, ae the nu- merous 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 unnas tural than co separate mosses for this reason from the other cryptogamic 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- if organ, would but increase the diffi- eulty. Gertner in the Introduction to his great work, p. 157, tells us he has seen many cotyledons in several fuci also, and that he suspects others of the more imperfect plants, hitherto referred to the monocotyledunes, may be similarly circumstanced. It seems that too much, by far, has been taken for granted in this department, though the parts un- der consideration form the great hinge upon which all natu- ral systems turn. It is only by analogy that the great family, or natural order, of lichenes has been judged monocotyle-— donous, an analogy which the fuci, if Geertner be correct, render very doubtful. The germination of the fungi is at least equally uncertain. I mean not however by any means to invalidate the im portance of the distinction between such plants as have two | or more cotyledons, and such as have only one or -none, however inaccurate the terms commonly used to distinguish them may be. Much less am T inclined to throw any need- less impediments in the way of those who labour ai the arduous and important study of natural classification, or to detract from the well-earned fame of such men as. Geertner, and 934° On the Differences : in the Structure of Calculi. Jussien, on account of difficulties and ‘imperfeétions un- avoidahle in, so abstruse a study. No real fricnd to truth and knowledge ever foments invidious rivalsbips 1 in philosophy. The faa of science is now'so vast, that its different cultiva-_ tors 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 pur-- sued by different paths, and nothing is more pleasing than to see the various observers of Nature in a Society like ours, mutually and barmoniously contributing, as we have all along done, to enrich the scientific hive. I would therefore donchide by recommending those who have leisure and op- portunity for the purpose, to observe for themselves the ger- mination 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-com- parison of Gertner’s work with the remarks in the fore- going pages. 9 XXXV. A Letter on the Differences in the Structure of Calculi, which arise from their being formed in different Parts of the urinary Passages ; ise on the Effects that are produced upon them, by the internal Use of solvent Medicines, from Mr. Witt1aM BranDE. to Everarp Home, Esq., F.R.S. {Concluded from p. 177.} Section VI. General inferences. I appears from the preceding observations, ‘that calculi formed in the kidneys, 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 toa continual current of urine: they also uniformly are deposited upon extraneous substances introduced into the bladder, but appear never to form’ small kidney calculi. ie : Th On the Differences in the Structure of Calculi. 935 “In what is commonly. called a fit of the gravel, a small uric calculus is formed in the kidney, and passes along the ureter into the bladder. it-is found from observation, that for some time after a “stone has passed from the kidney, the urime is generally un- usually loadc! with uric acid, and deposits that substance upon tae 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 prince paliy of the phosphates. Where ine disposition therefore to form uric acid in the kidneys is very great and permanent, the calculus found in the bladder ts principally composed of uric acid; but where this disposition is weak and of short duration, thie nucleus only is uric acid, and the bulk of the stone is composed of the phosphates. : ‘Where the increased secretion of uric acid returns at in- tervals, the calculus is composed of alternate layers of uric acid aud the phosphates. Other small calculi being formed in the kidney, make their way into the bladder, and afford fresb. nuclei; so-that set veral calculi are sometimes found in the same bladder, and their composition 1s usually nearly the same. ~ Jn other cases it happens, that a constant increased secre- tion of uric acid is going on from the kidneys, 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 i imprto- ‘perly, urate of ammonia, will be produced. We are entirely ignorant of the cause of the formation of _ the oxalate of lime, or mulberry calculus. I have frequently looked for oxalate of hme 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 se= -eretion. 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 236 4 ©On the Differences in the Strnetwré of Calculi. much less liable toa return of the complaint, than where, | uri¢ calculi have been voided. - Tn some rare instances we meet with calculi of the bladder which. are destitate of uri¢ acid and of oxalate of lime, the nucleus being composed of a hittle loosely agglutinated am- moniaco-magaesian phosphate, and the whole calculus con= — sisting of that substance, with variable portions of phosphate - of lime: in two cases I have met with calculi of this kind, composed of the triple phosphate only: they seem to be en- tirely formed in the bladder. N Having taken;this short view of the formation of caleull, I shall now,inquire into the action of solvents, employed either with a view. of effecting their solution, or of prevent- ing their formation andincrease, 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 matter voided by urine. | The different kinds of gravel voided by persons labouring under calculous complaints, may be classed in two ania 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 urie acid. The first species, which generally appears in the form of 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: of it does, emit an ammouiacal odour, and is not entirely soluble, in whicl case it.contains the triple phosphate of ammonia and magnesia. _ When this substance is.observed in the urine, the: alkalis are recommended. They are exhibited either in a pure state, er as carbonates, and im each instance’ the uric sediment ge- nerally diminishes rapidly, and during the continued nseraf alkaline medicines, occasionally: disappears altogether | i> .. hnweyer frequently happens: thao the matter voided: is — not On the Differences in the Structure of Calculi. 23% not diminished in quantity by the use of alkalis, but that ite form and composition are altered, and that 1t assumes the ap- pearance of a gray powder, and is composed of uric acid with variable portions of the ammoniaco-magnesian phosphate. From these facts therefore, it cannot be doubted that the internal exhibition of alkalis often prevents the formation.of uric acid, and hence must likewise prevent the increase of & calculus in the bladder, as far at least as uric acid is concerned; but it has also been supposed ‘that the alkalis are capable of acting upon the stone itself, and even of effecting its cem- plete solution. It is trae that if we immerse a calculus, com- posed of uric.acid, in a dilute solution of caustic alkali, that it will be slowly acted upon, and after some time entirely dissolved. if however we attend to what would take place im the body, we shall find the circumstances very different. That alkaline carbenates and sub-carbonates exert no ac= tien upon uric acid I consider to be completely established, both by the experiments of several eminent chemists, and those I have myself made upon the subject; and as there 1 at all times a quantity of uncombined acid in the urine, it © follows that although the alkali may arrive at the kidneys in its pure state, it will there unite with the uncombined acid,. and be rendered incapable of exerting any action upon. the ealeulus-in the bladder. Besides 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 exhaustion,.a large quantity of carbonic acid gas makes its escape; and when urine is distilled at very low temperatures, carbonic acid gas isgiven off: and also, when hime water 1s poured into urme, a precipitate appears, consisting of prema and carbonate of lime. : Lime-water, on account of the insoluble compounds which lime forms with carbonic and phosphoric acids, is even. more objectionable as a solyent than the alkalis. It may however be said, that if these means. prevent the increase of a calculus, material reliefis afferded to the: patient. How far the exhibition of alkaline remedies can be recom- mended upon these grounds, will appear, when the circum~ stances. 238 On the Differences in the Structure of Calculi. stances which attend the formation of the second species of calculus sediment or deposition in the urine, are-considered. | The ammontaco-magnesian phosphate appears under two forms: it is etther voided in a solid state, or in solution. In the former case it bears a good deal of resemblance to a white sand, and is frequently mixed with variable porportions of phosphate of lime. In the latter 1t makes its appearance after the urine has remained undisturbed for some bours in an open vessel, generally in ihe form of a fine pellicle, or of erystalline lamine, 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. Tiere is also a quantity of phosphoric acid present, which keeps another portion of the ammoniaco- magnesian phosphate, and also some lime (in the state of super-phosphate of lime) in solution. It is therefore obvious, that whenever the urine is deprived of a portion of the acid which is natural to it, the deposition of the triple phosphate, and phosphate’ of lime, more readily takes place: this is effected by the exhibition of the aikalhis. It may therefore be asserted, that although alkaline medi- cines often tend to diminish the quantity of ufic acid, and thus to prevent the addition of that substance in its pure state, to a calculus in the bladder; they favour’ the deposi- tion of the phosphates. It cannot be doubted that the alkalis reach the bladder, since in cases where large doses of sub-carbonate of potash have heen exhibited, I have seen evident traces of it in the urine. Where the phosphates only are voided, it bas 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 a 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 Observations on Mr. Brande’s Paper on Calculi. 239 might therefore be expected; but even then the nucleus of uric acid would remain, and thus a great deal of tine 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 Fourcroy and Vauquelin, who, in their paper on the composition of calculi, Jay down rules for its practice. Independent, how- ever of the impossibility of ascertaining the compusition 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 nuclei of calculi originate in the kidneys, and that of these nuclei 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 enlarge- ment: of the calculus, so that, while of a very small form, it may be voided by the urethra. 4.6 XXXVI Some Observations on Mr. BRANDE’s Paper on Calculi. By Everard Home, Esq., F.R.S.* Tar, call ii in the human bladder are not dissolved by the internal, use. of alkaline medicin:s, is an opinion which I shave long entertained, but the grounds of failure so. clearly pointed out by Mr. W. Brande, were not known to me: I 74 .) . ° : af, ’* From Philosophical Transactions for 1898. Part Il. only 9 240 © Odservations on Mr. Brande’s Paper on Calculi. only koow from experience, that, to whatever extent the. medicines are given, no such eflect takes/place. ‘The cire cumstance of the exterior laminz of calculi extracted from patients, who had persevered in a course of alkaline prepa-. rations, having been found softer than the parts towards the centre, has always been considered as a proof of the aetion of the medicines upon the calculus, and led to the belief, that where the stone was sinall, it might be wholly dissolved. This, however, Mr. W. Brandé has now proved to be a de- ception, and that the soft part is not a portion of the origt- nal calculus, but a newly formed substance, in which the uric acid is not deposited im crystals, but mechanically mixed with the phgspbates, and the animal mucus in the urine. Having met with cases, which confirm Mr. W. Brande’s ‘observations, it will be satisfactory to state them, as they may assist in doing away many erroneous notions generally en- tertained on this subject. The opinion, that calculi in the human bladder have been entirely dissolved, has received its principal support from 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 afterwards returned. This evidence appears to be very strong, but it avill be found from the followmg cases that it is not so im reality. Since the fallacy bas been detected in all the in- stances in which an opportunity was afforded of examining the bladder after death. Two of these] shall particularly no- tice, because they were published during the patient’s: dife- time in proof of the stone having been dissolved. Both patients were great sufferers from the symptoms of 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 effervescence, under the direction of the late Dr. Hulme: the cure was attributed to this medicine, and the case'was published in proof of its efficacy. ‘When the patient died T examined the bladder, and found twenty calculi; the latgest of the size of a hazel-nut, the others smaller. It appeared that the going off of the symptoms had arisen from, the poss terior, Olservations on Mr. Branae’s Paper on Calculi. 241 terior lobe of the prostate gland having become enlarged {a change which it frequently undergoes about that period of _dife), and having formed a barrier between the calcul and the orifice of the bladder, so that they no longer irritated that part either in the act of making water, or in the diffe- reng movements of the body, but lay tn the lower posterior part of the biadder without producing any disturbance. Their number preyented the pressure from being great upon any ene part of the intestine immediately behind the bladder, and their motion on one another rendered their external surface smooth, and probably prevented their rapid increase. The other patient was under a course of Perry’s hixivium 3, and when the symptoms went away, he published the case in proof of the efficacy of that medicine in dissolving the stone. IT examined the bladder after death, and found fourteen cat- 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. In several cases, in which I have examined the body after death, calculi have been found inclosed in cysts, formed be- tween the fasciculi of ithe muscular coat of the bladder, se 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 is-a-circumstance deserving notice, that in the case which gave celebrity to. Mrs. Stevens’s medicine, and pro- cured her a remuneration fram parhament; the bladder was not examined after death. é That calculi in the blader do sometimes increase, while the-patient is using alkaline mpedleMmess is fully proved by the following. examples, which also show that the uric acid and phosphates are formed in different proportions, according to . the peculiarities of she constituuon. A genileman who suffered from symptoms of stone was conan and a stone was found in his bladder. 1 pul. him onacourse of alkaline medicines, and he voided a small com- pact calculus, composed of uric acid, andevidently formed Vol, 32. No. 127. Dec. 1808. O° ia a 242 - Onthe Changes produced im hemos pias Air in the kidney. He was 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 capacity 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 toa 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- gan the use of alkalis, that they appear to have been formed after that period in the manner mentioned by Mr. W. Brande, A gentleman, who was found to have a stone in his blad- der, was persuaded that it was so small that it night be dis- solved, and with this view he took the fossil alwaliy beth 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 ahiclonses of 1th of an inch, was entirely composed 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 cal- culus were made up ofa mixture of uric acid and phosphates, so that the alkali had prevented the formation of -uric acid, but the phosphates were deposited more rapidly than before, A gentleman, in whose urine the uric acid appears in a solid form, immediately after it is voided, has the same ap- 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, XXXVIT. On the Changes produced in Atmospheric Air and Sys Gas by Respiration. By W. Aven, Abe F.R.S., and W. H. Pepys, Esq., PLRS.* a ee process of respiration, or breathing, is SO intimately connected with our existence in life, that from its first mo- * From Philosophical Transactions for 1808. Part I, _ ments, . and Oxygen Gas by Respiration. 243 ments; to the final close, sleeping and waking, this neces- sary action is constantly maintained: nor can it be suspend- ed even for a few minutes without considerable pain and the utmost danger.. This important process has of course ex- cited the curiesity both of ancient and modern philosophers 3 among the latter we find the distinguished names of Mayow, Priestley, Goodwin, Menzies, Spallanzani, Scheele, Lavoisier and Davy, whose successive Jabours have thrown great light upon this difficult subject, and prepared the way for further investigation; but it is impossible te take a review of what has already been done, without perceiving that some im- portant points were by no means satisfactorily settled ; an accurate method of separating the different gases, and as- certaining their exact proportion in any @iven mixture, was stil a desideratum when many of the experiments were made, and itis only of late years that eudiometry has at- tained its present perfection ; the quantity of residual gas in the lungs after a forced expiration was a matter in dispute among former experimenters, some making it one hun-_ dred and nine cubic inches, and others only forty; and vet itis of the utmost consequence in all calculations upon the effects produced, especially upon small portions of gas, that the state of the lungs should be accurately determi- ned ; this constitutes the great difficulty in the investiga- tions. We therefore commenced our labours by construct- ing an apparatus, in which we are able to respire from three to four thousand cubic inches of gas, conceiving, that in this quantity, the error arising from the residual gas in the lungs must be so much obviated as to permit the most satisfactory results. cg ‘ The apparatus consists of three gasometers, two of which are filled with mercury, and one with distilled water. 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 O02 are 244 - On ie Changes Sa tn Al mospheric Ae are all made to range with each other, so that the quantity of gas inspired and expired could be immediately and exactly ascertained :, to each of the mercurial gasometers a glass tube is fixed, and made to enter a mercurial bath, from which portions of the expired air could at any time be taken for exa- mination. By the kindness 9 our friend Silvanus Bevan, we are enae bled to give an-gccurate drawing of the apparatus. Description. Fig. 1. The cgmmunication with the water crasometer. “2, A cock so constructed that it might be made to coms municate with either of the mereueel gasometers, while at the same time al] connexion with the other was cut off. A. The mouth piece. Tig. 3. to 10. Brass cocks. G. 1. and G. 2. Mercurial gasometers. ac Scales graduated to cubic inches. M. Mercurial bath. The large reservoir or water gasometer is not shown in this drawing, it having heen so frequently described in che- mical works. Manner of condueting the Experiment. Our first care was, to be certain that all the parts of our apparatus were perfectly air-tight, and this, from the nature of it, was very easily ascertained 5 we agreed that the breath- ing should always be performed by one of us, and the regis- termg, &c. by the other, ‘as each would by that means ac- quire a greater degree of dexterity in performing his part, and the results would be more uniform. 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 even 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, fig. 1, and his right and Oxygen Gas by Respiration. 945 right hand on the cock, fig. 2, he opened the communication with the water gasometer, aud made an inspiration ; then immediately closing it, he opened with his right hand the cock at 2; and that at 4 being also opened, he expired into the mercurial gasometer G..1.; then closing 2, which cut off all communication with the mercurial gasometer, he opened 1, 1n order to make a fresh inspiration ; then closing it, he again opened 2, and expired into the mercurial gaso- meter ; 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, bya 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 ex- pelled.. 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 the 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 experimenits. i Cubic inches Cubic inches No. Time. ofcommonair ofgas Deficiency. inspired. expired. i. timenotnoted 3760 3741 19 2. 11 minutes 3900 3869 — 31 3. 101 ——— 3624 3620 4 4. 10; ————- 3570 3550 20 Je il ———- 3685 3653 32 6. 11 ——— 3380 3355 25 7° 10, ————. 3180 3141 39 S. 10). ——_—_ 3360 3298 64 9. io. ——— 3290 3267 23 10,5 °11—— 3580 3343 37 Tn this Jast experiment we ascertained that the expired gas contained 8 per cent. of carbonic acid. Ors. y The 2946 © On the Changes produced in Atmospheric Air The breathing in these cases was as ‘nearly natural as we conceive It possible to be in any apparatus ; the operator was. scarcely fatigued, and his pulse not raised more than about | one beat in a minute; the respirations however were deeper, and fewer than natural, amounting only to about 58 in eleven minutes, whereas from repeated observations at different and distant times he makes 19 in aminute.’ The smallness of - the deficiency surprised us very much, as, from the reports 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 under these circumstances has suffered no perceptible dimimution by standing for a considerable time; in one case, in which air from the lungs was driven into the mercurial gasometers for twenty-seven! minutes, the temperature of the quick- silver at the end of the experiment was not raised half a de- gree of Fahrenheit’s thermometer. The deficteney, in our opinion, principally arises from the difficulty in bringing the Jungs precisely to the same state after, as before the expe- riment ; and it must be recollected that the operator come menced bya forcible expiration inte the open air, but finish- ed by a forcible expiration into the mercurial gasometer. 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 the complete evacuation in the latter case than in the former, and consequently the Jungs might contain a few inches more after the experiment than before it, which might in some measure account for the deficiency. - Inthe eleventh experiment, portions of gas were taken off from each of the mercurial gasometers as they were filled, and these portions being afterwards mixed were carefully examined. . Eleventh Experiment. : Cubic inches #7, 4:-) + nN Barom. ies Time. of common air ae Deficiency. et inspired. Pee re 30°4 50° Ilmin, 3460 3487 83 To at and Oxygen Gas by Respiration. 247 _ 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 parts; 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 lime-water in the eudiometer, the lime-water became turbid, _and 8°5 parts of the gas were absorbed, which were conse- quently carbonic acid; the remaining 91°5 parts were treated with the green sulphate of iron, saturated with nitrous gas, as recommended by professor Davy, and afterwards with the simple solution of the green sulphate, when 12°5 parts were absorbed, which were consequently oxygen, and the remain- ing 79 azote. 100 parts of the expired gas therefore consisted of © 8°5 carbonic acid. 12°5 oxygen. 79° azote. re 100 The air contained in the water gasometer, previous to the experiment, being examined by the same tests, consisted, in 100 parts, of 21 oxygen. 79 azote. ee i100 In trying common atmospheric air with lime-water, we could never find any quantity of carbonic acid perceptible i in the egdiometer of 100 parts. Calculation for Carbonic Acid. 100 : 85 :: 3437 : 292°145. So that 299°14 cubic inches of carbonic acid gas were given, off in eleven minutes, or 26°55. cubic inches per minute, which is almost exactly the estimate of professor Davy. ! O04 In 948 On the Changes produced in Atmospheric Air _ Tn this experiment the operator inspired 3460 cubic inches in eleven minutes, and felt himself in a natural state when he left off. Then, as he makes usually under common cir- cumstances nineteen respirations in a minute, 5460 1 g.5 11 x 19 = 209 209 it follows, that he takes in 16} cubic inches at every easy in- | spiration. As all the experiments had been hitherto made upon the lungs of one person, we concluded that the next should be performed upon our assistant. ‘\ Twelfth Experiment. mee Cubic inches Barom. Eker: Time. of common dir Cubic inches Difference. Fahr. 2 expired. \ inspired. 30°83) 56°) 75h min... 3300 3311 11 increase. Here, as usual, the lungs were exhausted both before, and at. the close of the experiment. The excess of eleven cubic inches, in this case, no doubt arose from the person not having been in the habit of ex- hausting his lungs, so that they contained more when he began than when he left off; his lungs appeared to be of - greater capacity than those of the usual operator. Portions of gas were saved’ from each of the mercurial gasometers as they were filled, which being mixed together, for the average gave the folluwing results : 100 parts of the mixture contained 8*5 carbonic acid. Cet k 12°5 oxygen. 9° azote. 100 Calculation for Carbonic Acid. — YOO" 2 YSIS" ss SSA eee into. Consequently 281°43 cubic inches of carbonic acid gas were given off in 54 minutes. In this experiment we meet with a remarkable fact, viz. that as much carbonic acid gas was given off in 52 minutes, as inthe former experiment in eleven minutes ; so that it appears, and Oxygen Gas by Respiration. 249 appears, whenever atmospheric air is taken into the lungs, it returns charged with about 8 per cent. carbonic acid. The faster respiration is performed, the more carbonic acid is given off, and consequently the more oxygen consumed : -in this instance it was given off at the rate of fifty-one cubic inches per minute. Thirteenth Experiment. ) We now proceeded to carry on the respiration of common air far a much longer period than usual, and of course on a much larger quantity. The experiment was made by the same operator who had performed all the other, except the ‘leth. Eleven mercurial gasometers having been filled, taken - off, and registered, the operator continued to breathe in the igch until a mark was made by his colleague upon the scale of the water gasometer, and it was again filled with common air to the usual division on the scale. This occupied but a very short space of time. The operator, without taking his lips from the tube, then filled twelve more of the mercurial gasometers, which were registered as before, and he conti- nued to breathe in the 12th, until the water gasometer Was: again replenished ; ; eleven more were then filled, and por- tions saved from each: the experiment was completed by a forcible expiration of 166 cubic inches into the 12th : and this last portion being left for an hour and a half was not perceptibly beatles sna in yolume. Cubic inches he Barom.’ ane Time. of commion air pean Deficiency. Bai inspired. Bee BGISS, [EB 2A 3G: 9890 \ 9872 18 The breathing was so nearly natural that the operator was scarcely fatigued, and thought that he could have gone on for a much longer time. The Seaulluas’ of the deficiency, notwithstanding the ex- periments occupied 24} minutes, is a striking circum- stance, and leads us to suspect still more strongly, that the deficiency principally arises from the impossibility of always bringing the lungs to the same state after forcible expiration. 100 parts ©50 On the Changes produced in Atmospheric Air 100 parts of the mixture of expired gas gave 8 carbonic acid. 13 oxygen. 79 azote. \ « 100 © Calculation for Carbonic Acid. TOO. S287 ss 7/89" 76: So that 789°76 cubic inches of carbonic acid gas were given off in 242 minutes, which gives thirty-two cubic inches per minute. But here it must be noticed that the respiration was more rapid than in the 11th experiment, and a larger quantity of carbonic acid given off in the same time. ‘This agrees with the 12th experiment. We are very much inclined to think that, in ordinary re- spiration, a great part of the air is returned unaltered, viz. 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 experiments made with a view to this subject, a small quantity of the first portions, given off in a common and natural expitation, was received in a vessel over mercury ; on examination, it only contained 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 ex- periments, to be about eight. The operator, after rather more than a natural inspiration expired 204 cubic inches into the mercurial gasometer, making his utmost efforts to press a3 much as possible out of the lungs, this contained 9°5 per cent. of carbonic acid. Here we are to recollect, that these 204 cubic inches contained the first, as well as the last portions ; the first portions have been proved to contain only from three to. five per cent. ; consequently the last portions must contain : more and Oxygen Gas by Respiration. 25 miore 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 *. | Three hundred cubic inches of atmospheric air were ad- mitted into the mercurial gasometer G.1.; the other, G. 2, was empty. The nose being properly secured, and the mouth applied to the tube A, as usual, air was drawn from G.2, _and by half turning the cock, 2, was expired into G. 2. This was reseated until the contents of G. i. had been made to pass through the lungs, and transmitted to G. 2. The air was then inspired from G. 2, and expired into G. 1, until G. 2 was nearly empty. This was repeated about cight or ten times during three minutes, until respiratien became ex- tremely laborious, and the operator desisted. The whole 300 cubic inches must have passed eight or ten times through the lungs 5 and we confidently expected, that en examining the air we should have found an unusual pre- portion of ee acid. But 100 parts gave only 9°5 carbonic acid. 5°5 oxygen. 85° azote, cee 100 ‘ Here was an increase of six parts in 100 of something which the tests for oxygen would not take up, and also a loss of six per cent. oxygen. This seemed to convince us, that under certain circumstances, as during some peculiar alteration in the vital functions, gaseous oxide of carbon, carburetted hydrogen, or some other gas uot absorbable by lime-water or the tests for oxygen, might be given off from the lungs, and we accordingly determined to repeat Cruikshank’s ex- ‘periments with hyperoxygenized muriatic acid gas, * In this experiment there was obviously no occasion to make allowance for the air contained in the tubes and sockets. ‘We find its volume to be eighteen gubic inches. We ae = 252 On the Changes produced in Aimospheric Ait ie, We procured the gas from hyperoxygenized muriate of — potash. by means of muriatic acid, and mixing it with 4 known portion of gaseous oxide of carbon in a Aint stopper — bottle, the mouth of which was immersed in mercury for twenty-four hours,the gaseous oxide of carbon was converted into carbonic acid gas, as was proved byits effects upon lime- water, which, when both the gases 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 carburetted Aydrogen, if any should be contained in the expired was. Frcm a conviction of the importance of these eps we. were determined to take nothing upon trust. Fifteenth Experiment. “ We repeated the 14th experiment with alittle variation. In this case we employed only one of the mercurial gaso- meters, into which exactly 300 cubic inches of atmospheric air were admitted. The operator having made an easy ex- piration, applied his mouth to the cock at the top 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 se- cond minute-his whole attention seemed to be withdrawn from surrounding objects and fixed upoy the experiment. He now experienced that buz in the ears which is noticed in breathing nitrous oxide, and after the third minute he had only sufficient recollection to close the cock after an ex~ piration. This~secured the result of the experiment 5 ; but he became so perfectly insensible that, on recovering, he was much surprised at finding his friend and the assist- ant on the table in the act of supporting him. It was noticed that he had made thirty-five inspirations during the experiment. We now examined the air which had been so treated. 1 100 parts ~ ppats . and Oxygen Gas by Respiration, 253 100. parts contained 10 carbonic acid, 4 .oxyven,. 86 azote. 100 os S In this experiment it is remarkable, that the air which had. been so often through the lungs, should only have furnished i0 per cent. of eambonie acid, suite the air which passesthem but once contains from 8 to 8°5. Here the oxygen had lost 7 from 21, 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 oxygen for its formation; the ten parts of carbonic acid may therefore be reckoned as oxygen, which would make the constitution of ; : 14 oxygen, the eas after the experiment aa = P Bet 86 azote. . ; 21 oxygen. whereas before the experiment it was ys ; 79 azote. “Now we did not suppose the residuum of 86 to be all azote, though 79 might be ; therefore seven parts appeared to have been added by this unnatural mode of respiring, and we conjectured the Se utstos might be gaseous oxide of carbon, To ascertain this, we put 40 parts into a Aint stopper, bottle, and nearly filled it with about 100 parts hyperox- ygenized muriatic acid, procured as before, and recently pre- pared; the stopper being put in, over distilled water, we plunged it in pursioe ae and filled a second bottle in the same way, as a comparative experiment. We next procured some pure azote, by absorbing the oxy- gen from 4 portion of atmospheric air by the saturated green sulphate and simple green sulphate as usual ; 40 parts of this azote were mixed with the same proportion of the acid gas as inthe 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 after- * See the experiments on carbonic acid in fate Society’ 6 Transactions, wards 254 . On the Changes produced in Atmospheric Air wards in the eudiometer with the tests for oxygen ; and there were still exactly 40 parts Jeft; proving that the hyperox- ygenized muriatic acid gas has no action upon azote. ' We then examined the bottles containing the residuum from the air that had been so often respired, and found that | 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 oxygen 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 ex- periment contained 21 oxygen, 79 azote in 100 parts, making the total quantity ofoxygen 63 cubic inches, azole 237 300 Now if the Jungs be capable of fixing permanently any azote from the atmosphere, it appears by our experiments that the quantity must be very minute, seeing that in the Yith, 12th, and 13th experiment, it did not disturb the pro- portion of azote, as shown by the eudiometer ; we shall there- fore 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 oxygen, either in the form of carbonie acid, or free. ; SG 21a fen Oa 7 (enema ee Therefore the total quantity of oxygen left after the experi- ment would have been 38°58 cubic inches. Then 237 azote + 38°58 oxygen = 275°58 the quantity of gas after respiration would dhatetoie have been 275°58 cubic inches. 300 — 275°58 = the loss of oxygen, or 24°42 cubic inches. It appears, therefore, that 24°42 cubic inches of oxygen had been and Oxygen Gas by Respiration. : 255 been absorbed by the system under the circumstances of this experiment. Reviewing the 14th experiment, it appears that the gas after respiration contained 85 per cent. azote, and 15 per cent. oxygen, either in the state of carbonic acid, or free. Slate of the Air hefore the Experiment. 300 = 237 azote + 63 oxygen. After ihe Experiment. So 05 os 257 2 41°89) The total quantity of oxygen after the experiment appears to. be 41°82 cubic inches. Then 237 azote + 41°82 oxygen = 278°82. The total volume after the experiment appears to be ie 82 cubic inches. 300 — 278°82 = 21°18. The loss of oxygen in this case was 21°18 cubic inches. We are disposed to consider the 11th as a standard expe- riment relative to carbonic acid gas, because the quantity of air respired in a given time is pretty near the average of the first ten experiments; and because it very nearly agrees with the statement of professor Davy. In this experiment 292: cubic inches of carbonic acid gas were given off in eleven minutes ; the barometer was 30°4, the thermometer 50°, the volume being calculated at the mean, viz. barometer 30, thermometer 60°, will be 302 cubic inches given off in eleven minutes, or 39534 cubic inches in twenty-four hours, sup- posing thé production to be uniform during all that period ; and as 100 cubic inches of carbonic acid gas weigh 47°26 grains, 100.: 47°26: : 390534 : 18683°76; the weight of the carbonic acid gas amounts to 18683°76 grains; and estimating the carbon in it at 28 parts in 100, 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 crains ; it will follow that 5363°55 ers. or above 11 02. troy of solid carbon, are emitted by the lungs in the course of twenty- four hours; and that 39534 cubic inches of oxygen gas are consuined in the same time. But when we consider that in respiration perfectly natural, a much smaller quantity of air 256 — On the Changes produced in Atmospheric Air aN air can come in contact with those parts of the lungs caleu- | lated to act upon it, the proportion of carbonic acid gas © given off in natural respiration, ought probably to stand’ ~ considerably lower than in the above estimate; but at all _ events it will be very considerable. 2 then Sixteenth Experiment. ; Having made so many experiments upon atmospheric air, | we now proceeded to ascertain the effects produced upon oxygen gas by the process of respiration. The water gaso- meter was filled with oxygen gas made fron: the hyperoxy- genized muriate of potash by heat, care having been taken te clear all the tubes, &c. as much as possible of common ; air, by forcing a quantity of oxygen gas through them.. One hundred parts from the water gasometer being treated with the uswal-tests in the eudiometer, a residuum of only 2-5 was left; so that 97°5 per cent. were pure oxygen, and the rest azote. if The register of the water apparatus being noticed, and the operator having prepared himself as usual by a foreed expi- ration, began to respire; his pulse was 72; and at the end of nine minutes and twenty seconds, the experiment was concluded by a forced expiration, when the pulse was raised to'BS." = Cubic Inches Cuh, Inc Barom. bo a de Time. of oxygen gas ae Deficiency. 2 mspired. pee: 5 20°5 53° 9”-207 3260 3103 67 The operator felt a general glow over the body to the very extremities, with a gentle perspiration ; this howeyer went. off in a few mimutes, and no remarkable deviation from the ordinary state was experienced. A portion having been saved, as usual, from each of the mercurial gasometers, for an average, 100 paris contained ii carbonic acid, 83 oxygen, 6 azote. eae ee 100 The examination repeated, gave the same results. = ‘ Calculation = = — anid Oxygen Gas by Respiration. 257 Calculation for Carbonic Acid. 100: 11:: 3193 : 351°23, consequently, 351°23 cuibic inches of carbonic acid gas were formed in 9-20”, or 37:64 cubic inches in a minute.’ Here itis plain that a greater quantity of carbonic acid was formed from oxygen than from common air, in the same time 3 and hence we infer, that one use of azote is to” regulate the quantity of oxygen, which shall be taken up in the act of respiration. The gas inspired was 3260 cubic inches, and of this 2°5 per cent. was azote. 100: 2 2:5) 3/3260 -:/ 8+ 50. The total quantity of azote in the gas inspired, was there- fore 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 oe of azote be- fore respiration was only 81°50. 191°58 — 81°50 = 110°08; therefore 110°08 cubic inches were added by the process of respiration, beside what little remained in the lungs we the experiment. Galeulation for Oxygen. The 3260 cubic inches of gas inspired contained 81°50 azote. 3260 — 81°50 = 3178°50, and consequently the pure oxygen was 3178'50 cubic inches. ‘The 3193 cubic inches of gas expired, contained 83 per cent. of free oxygen, and 11 per cent. in carbonic acid gas, making together 04, 100: 94:: 3193 : 3001°42. The oxygen gas, found after the experiment, was there- fore 3001°42 cubic inches, and deducting this from the oxy- gen before the experiment, $178°50 — 3001°42 = 177°08. It appears, at first sight, that 177°08 cubic inches of oxygen were missing, but great part of this may be accounted for, by adverting io the state of the lungs after the experiment. Vol, 32, No. 127. Dec. 1808. | lay The 258... On the Changes produced in Atmospheric Air ’ The addition of 110:08 cubic inches of azote, we consider as arising from that portion still retained in the lungs, not- ; withstanding the forced expiration at the beginning of the experiment, and considering that in the 14th and 15th ex- periment, 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 residual air contained in the lungs after a forced expiration may amount in 100 parts, to not more than 16 oxygen and 84 azote: any one who reflects upon the structure of the Jungs, and the minute ramifications of the extremities of the bronchial ves- sels; and when he also considers that those parts of the lungs with which the air comes in contact, if spread out, would present a surface equal to that of the superiicies of the whole body ; and lastly, that this viscus 1s 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 por- tion of air must remain tor a considerable time in contact with the internal surface of the lungs, where it is liable to lose a portion of its oxygen, but also that the residual quan- tity of air in the lungs, after the most violent attempts at expiration, may be very considerable. It is to this cireum- stance that we attribute the excess of azote in the experi- ments upon oxygen, and pretty deep inspirations of this gas having been made during 9’°20", the azote must have been’ in great measure displaced. Admitting then that the air cided in the lungs, before the experiment, consisted of 16 oxygen, 84 maeerek and at the conclusion of the experi: ment of 94 oxygen, 6 azote, then we have 84r azote at the begining, i 100 - ©" azote-at the end. OK SO Rid gett = . 6x 842 ' ua } Se 00° 100 is 210% 840 6L = — ‘or, 842 — D = *780. Reh 100 Oa 'g . ae . is “wad a. 10. or 341 cubic inches ; } Hs Therefore: upon this ‘calculation. it appears that 141 eubie inches and Oxygen Gas ly Respiration. - 259 inches of gas remained in the lungs after a forcible attempt at expiration; then the state of the Jungs before the, aren ment must have been 118°44 azote, 22°56 oxygen. 14] And after the experiment, 132°54 oxygen, 8°46 azote. 141 Catculation on total Quantities. Azote before the experiment, 81°50 cubic inches, — ea in-the Jungs, 118°44 199-94 ‘ Azote after the experiment, ~ found by the tests, — “191° 58 UG; ~ ~ contained 1 in the lungs, | ea “46 ai ROP LB ESTO mre 7 ee ; , Oxygen rein the experiment, 3.17830... contained i in the lungs, 22: 56). 3201:06 Oxygen after the experiment, C0 are 4 — found by the tests, 3001°42 - contained in the lungs, 139°54 OSB) ul P80 5 1 BI BHAQG Total: of oxygen. pelos the experiment, 3201°06 Total of oxygen after the experiment, | 3133°96. | Difference 67" 10 ‘The deficiency noticed in the experiment was 67, supposing that the lungs were brought to the same state after as before the experiment ; but granting that this was not the case, - R2 and 260 On the Changes produced in Atmospheric Air 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 eas was 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. ‘The water gasometer was filled to the usual mark upon the scale, with oxygen gas, prepared from about 9 oz. troy, of hyperoxygenized muriate of potash, as in the former experi- \ ment; the gas being examined was found to contain as be- fore, 2°5 azote, ant 97°5 oxygen, in 100 parts. The apparatus being found air-tight, and all the tubes, &e, cleared of aymospherte air by passing oxygen through them, the operator, prepared himself for the experiment ; but it must be noticed that he had been rather fatigued during five hours previous to respiring, and had not taken any refresh- ment ; the weather was very warm; his pulse 86; heat under the’tongte 987; he felt ‘no ungomoreale sensation during the process, but experienced a gentle glow and uni- versal perspitation, breathing all the time with great ease ; his pulse after the experiment was 102, and the heat her the tongue 99°. Cubic Inches ‘Therm. : Cubileshes Barom. iq Time. of oxygen gas ee penceney: 30°3 70° 7’:95' #3420 3362 - 58. The quantities of expired gas taken off in each of the mer- curial gasometers were as under, in the order i in which’ they were filled. No, 1. - - 250 cubic inches. - 2. =, 42 ~ 290 ah - = 212 4, = - 238 ~ | lich ite mete a 2 cebnti 6. ts - 30G " da ‘ 6 7. and Oxygen Gas by Respiration. 261 Be - - 241 Ss. = - 296 - 9. = - 256 10. - - 256 ui: - - 286 Bei = = 257 13. - = 168 3362 The 13th gasometer was the whole of the last single and forcible expiration ; portions were sayed from each of the gasometers, and we first examined the state of Ne. 1. 100 parts contained = y carbonic acid, 25 azote, 66 oxygen. =e 100 The large quantity of azote in this case was a clear proof that our conjecture upon the residual gas in ithe lungs was. well founded. We then examined a mixture of No. 2 and 3. 100 parts contained 10°5 carbonic acid, 10 azote, 79°5 oxygen. 100 Here the quantity of azote was diminishing, and the ratio of carbonic acid increasing ; so that it appears necessary for the lungs to be cleared of are before the erased Bipuer on | ef carbonic acid can take place. The 13th or last gasometer was now v examined by itself: 100 parts contained 12% carbonic acid, : 5°5 azote, 82° oxygen. =n i 100 Here the proportion of azote was only 3 per cent. more than. what existed previously in the gas; and hence we may con- clude, that even seven minutes and ahalf was notasufficient time to remove the azote from the extremties of the bronchia. R3 : We 262 On the Changes produced in Atmospheric Air We lastly made a mixture of all the gasometers, from 2 to 12 inclusive, and found that 100 parts contained 12 carbonic acid, > 6°5 azote, , 81°5 oxygen, 100 oe \ Calculation for Carbonic Acid. $00: 9:: 250: 22°50 Carbonic acid gas in No. 1. 22°50 - 100 :12°5:: 186: 21 ditto . No, 13. @t From > 3362 total expired 250 No. 1. 168 No. 13. —— Deduct 418 ' ‘Leaves the mixture 2944 of No. 2, to No. 12. ¥00 : 19=: 2944 : 353-98 Carb. acid gas immuxture 453-28 , 2. to 19. a -396°78 The total quantity of carbonic acid gas emitted, was there- fore 39678 cubic inches. Calculation for Azote. 100: 2°5:: 250: 62°50 AzZotei in Ai Wo Vvan Pe 62°50 100: 5°5 :: 168: 9°24 —in No. 73. 24 VOO : 65 +: 2944; 191°36 © -—— in mixt. 2. to 12. 191-36 263-10 The azote expired, beside What might be contained in the lungs, at the close of the experiment, was therefore 263-10 cubic inches. Here it is plain, that the operator, at the be- ginning of this experiment, had not brought his lungs to the same state as in the preceding; or that in consequence of fatigue, and want of Teer a for several hours, the pro- portion.of azote in the lungs might be greater. . Every 100 parts of oxygen, before it was inspired, con- fained.2°5 azote, . 7. : 100 \ and Oxygen Gas by Respiration. 263 100 : 2°35, 3. i620 6 85°50 5 Consequently it contained 85:50 cubic inches of azote. From 263-10 Deduct 85°50 the original azote, 77-60 will be left for the increase of azote. Then supposing as before, that the quality of the air in the lungs, before the experiment, was 84 per cent. azote, 16 oxygen, and after the experiment 5°5 per cent. azote, 945 oxygen, as found in the last gasometer, we take 84x 5 ae es NB sop azote at the beginning, mt azote at the end; 55x 84x 100 ab at COr 100 S4r 55x 177:60 = (= = OF 84 — *0557 = shy Gods 100-100 So Dyr6o: “7 ee it appears, that previous to the experiment, the lungs contained in this instance 226 cubic inches ; and if we suppose them to be in the same state after, as before the experiment, | the quality of the gas in each case will be as follows : Contents of the Lungs before the Experiment. 189°84 cubic inches of azote, 36°16 oxygen. , or 226 cubic inches. - 226 Contents of the Lungs after the Experiment, 12:43 cubic inches of azote, 213°57 oxygen. 296 Calculation for Oxygen. 3420 — 85°50 = 3334°50 original oxygen, Add 36-16 in the lungs before the experiment. Pa Jy fy total quantity of oxygen before ee 10;08 1 the experiment. R4 3 After 264 On the Changes produced in Atmospheric Aig : After the Experiment. 100: 66 ::250 2165 oxygen in No. 1. 165 100: 82 :: 168 :137°76——— in No. 13. 137°76 100 : 81°5:: 2944:9399°36 —— in mixt.2.t0 12, 2399°36 in carbonic acid 396°78 ——— in lungs after expt. 213°57 i ys 3312°47 . ; 3370°66 original oxygen, —— 3312-47 after experiment, 58°19 deficiency. Meee The observed deficiency in this experiment was 5S. - The deficiency in this case, and in the former experiment with oxygen, though comparatively small, when contrasted with the quantity of gas respired, is larger than the average with atmospheric aif: 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. | Eighteenth Experiment. Cub. Inches. ike Sores Barom. Therm. Time. of oxygen gas expired. Deficiency. inspired, 30°15 70°), 0 8 ae". oem 3060 70. The operator breathed as usual, after having made a strong effort to exhaust his lungs ; his pulse before the experiment was 84, the thermometer under his tongue 98°: after the experiment his pulse was 96, and the thermometer under his tongue still 98°; the same gentle glow and perspiration was felt as in the other experiments on oxygen; a portion of the gas was saved from each of the mercurial gasometers, and their amounts were as under: __ No. 1} }, - - 196 2. - => 228 Sie - = 284 4. - = 294 Be ii) Stig = 248 Gewese 3s 280 Te a ~ 258 ‘ i f _ ard Oxygen Gas by Respiration. 265 8, ON 272 OSE (aia a ea = 250 10. - ay 304 VY: - = 22 12, L398 3060 No 1, tried by itself, contained in 100 parts, 9 carbonic acid, 22- azote, 69 oxygen. 100 No. 12, the last, contained in 1C0 parts, 12 carbonic acid, 5 azote, 83 oxygen. 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 experiment, and show,that the proportion of azote continues to diminish, as the expe- riment praceeds, and also that there is a larger proportion of carbonic acid given off when oxygen is employed, instead of atmospheric air. by In this recital of experiments, which have occupied a con- siderable portion of time and attention, we have endea- -voured to give a plain statement of facts, from which every one may draw conclusions for himself; we shall here, how- ever, take the liberty of briefly recapitulating the principal _ of those facts, and submitting what seems to us the most obvious inferences. 1. It appears that the quantity of carbonic acid gas emit- ted is exactly equal, bulk for bulk, to the oxygen consumed, and therefore there is no reason to conjecture that any water _is formed by an union of oxygen and hydrogen in the lungs. 2. Atmospheric air once entering the lungs, returns charged with from 8 to &5 per cent. carbonic acid gas, and j when 266 On the Changes produced in Atmospheric Air, Se. when the contacts are repeated almost as frequently as PRE - ble, only 10 per. cent. is emitted. if The 12th and 13th experiments prove, that when the in- spirations and expirations are more rapid than usual, a larger ' guantity of carbonie acid is emitted in a given time ; but the proportion is nearly the same, or about 8 per cent. The pro- portions of carbonic acid gas, in the first and last portions of a deep inspiration, differ as widely as from 3°5 to 9:5 per cent. 3. Considering the 11th as a standard experiment, it ap- pears that a middle-sized man, aged about thirty-eight years, and whose pulse is seventy on an average, gives off 302 cubic 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 1102. troy; the oxygen consumed in the same time will be equal in volume to the carbonic acid eas ; 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 alf* the experiments were made between breakfast and dinner. 4. When respiration is attended with distressing circum- stances, as in the 14th and 15th experiments, there is reason to conclude that a portion of oxvgen is absorbed 5 and in the last of these experimet uts, we may remark, that as the oxygen decreases in quantity, perception gradually ceases, and we may suppose that life would be completely extin- guished on the total abstraction of oxygen. * §. Alarger proportion of carbonic acid gas is formed by’ the haman subject from oxygen, than from atmospheric air. 6. An easy, natural inspiration 1s from 16 to 17 cubic inches in the subject of these experiments, who makes about 19%!’ a minute; this, however, will vary in different indi+ viduals, and perhaps we ought to estimate the quantity of earbonit acid gas, given off in perfeetly natural respiration, at somewhat less, and most likely at considerably less, than in the statement above, when we consider that in short inspi- rations the quantity of air which has reached’no further than the \ = : On Commerce. 267 the fauces, trachea, &c. bears a much larger proportion to the whole mass respired, than when the inspirations are deep. 7. Nohydrogen, nor any other gas, appears to be evolved during the process of respiration. 8. The general averag? of the deficiency in the. total amount of common air inspired, appears to be very small, amounting only to about 6 parts in 1000, and we are in- clined to attribute it in great measure to the difficulty in ex- hausting the lungs as completely after an experiment as be- fore it; the first expiration being made’ into the open air, . the last into the apparatus, g. The experiments upon oxygen gas prove that the quan- tity of air remaining in the lungs and its appendages is very considerable, and that, without a reference to this circum- stance, all experiments upon small quantities of gas are liable to inaccuracy. Other important conclusions might perhaps be drawn from the facis related in this paper: but having already trespassed lareely upon the time of the Society, we shall abstain from any further remarks, until v we bring forward a new series of experiments, XXXIX. On Commerce. By Mr. James Grauam, of Berwick-upon- Tweed. To Mr. Tilloch. “SIR, ROM some circumstances seedless to mention, I did not see your Magazine till a few days ago, in which some re- niarks are wide on my Essay on Commerce. Before I again enter upon this subject, permit me to ree turn my Best: thanks to Mr. Lapis, for the mild and candid manner in which he has offered his remarks. JT am much obliged by his giving me an opportunity of further illus» trating and proving the propositions I laid down in my for- mér Essay; but after all, if it should appear that some of my opinions were erroneous, the sooner my error is detected ; the 2868 On Commerce. the better. LE have long been of opinion, that freedom of discussion is the highest privilege that either a nation or an individual can enjoy, whether in regard to commerce, poli- tics, or religion. Let error hide its haggard face, shrink from inquiry, or shelter itself under laws, pains, or penal- ties. Truth has nothing to fear: the more it 1s tried, the. more it is examined, like a fair and upright character it will only appear more amiable, and shine with a brighter lustre. It would appear from the remarks of Mr. Lapis, that I had not expressed myself in so clear a manner, but that some doubt might arise as to the real meaning of the proposition T laid down relative to the laws of nature, pointing ont the true principles of commerce, and that in all our commercial regulations we ought to keep those laws in the order of ma- ture constantly in view. In the di versified productions of the world which we inhabit, I endeavoured to trace the first principles of commerce, by every country having some su- perfluities, and that there was no country but had some wants; that a mutual intercourse was of reciprocal advantage ; that all prohibitory laws, or excessive duties, were counteract- ing the benevolent dispensations of the Supreme Being, that no laws however severe, nor any regulations however mul- tiplied, would prevent ilicit trade where there was too strong © a temptation ; that this was encouraged and supported by the present impolitic laws, and such had a very bad effect on the morals of the people, . To have illustrated all these in a full and proper manner would have required a volume; I only mentioned what struck me. at the time as being most» evident, and generally understood by the middling class of society. I will now endeavour to answer some of Mr. Lapis’s fo jections. He says that the laws or order of nature are the rer verse of what I had stated, because every country does, or with proper cultivation will, produce all those articles neces-. sary for the support, &c., of the inhabitants, and that the natural produce of every country, is the mast congenial to the health and support of the people. * Now I fully admit the truth of Mr. Lapis’ i in a certain degree, but I do not conceive that it in the.least ‘ey either On Commerce. 269 either weakens or invalidates my former propositions, (viz.) That there was no country, however highly it may be favour- ed; which can produce olf that is necessary for the comfort, health, protection, and security of its inhabitants. I will here confine my observations to our own country: at the same time I am confident that in a great variety of articles such observations are applicable to every nation. T believe none will deny that this country is highly favoured, whether ‘we consider the mildness of the climate, the pro- _ductiveness of the ‘soil, the astonishing improvements in agriculture, the skill and persevering industry of our manu- facturers, the enterprising spirit of our merchants, &¢.,—Yet with all these how numerous aré our wants ! It is a fact well ascertained, althouch not eenerally known, that this country does not on an average raise as much corn as is absolutely _ necessary for the support of the inhabitants. When this is the case, it would certainly be worse’ than folly to’ occupy any part of the land which is ‘proper ‘for the ‘production of eorn to any other purpose. How/are'we to procure our flax and hemp? the consumption of which, I scruple notte say, as immense; and I think it will be generally admitted, that the various purposes’to which’ linen is adapted add much, very much, to our comfort, in'almost innumerable instances. ‘Now for protection, ‘without these two’ articles’ what would _ become of our navy, the glory and ‘boast of our country,/as weil as'‘all the vessels employed in commercial ‘concerns? But this is not all’; for'even in wood we are deficient, parti- eularly for masts, as well a3 some other kinds needless to mention. Another artiele for which we are entirely depen dent on foreign supplies is gunpowder, which in the present state of the world (and there is no appearance of ils’ being better) is ‘of the most absolute necessity. Must we not bring ‘our sulphur froniabroad, and our nitre from almost the ends ofthe earth? f turn my eyes to our large bleaching-srounds z From whence do we draw the privé iat materials for Hélkauine and whitening our linen, by which means it is’ reridered fit for all the various purposes to which itis adapted? LL sur- wey our more extended printf fields in all their various de- Lo itepiia but” particularly in‘the variety of those colours where 270 On. Commerce. where the skill of the artist almost rivals the blossoms of Nature, Must we mot procure the greater part from other countries? And unless the present. order.of the universe is changed, no human art can cultivate, to any extent, many of the dyeing-woods, and many other articles which are) es- sentially necessary in cur manufactures. Any person tolee rably conversant with these branches of trade or, manufac- ture, will easily perceive. that ] might strengthen my argu- ment by a great variety of observations: but, for this my own time will not admit; besides, it would be obinitinne too much room in your useful Miscellany. é. I will now heg leave to.examine how far, this country, can, or actually does) produce all that is necessary for health. As I make no pretension toa knowledge ot the materia medica, I will confiné my observations to such articles as are generally admitted to be essentially useful. Bark is certainly ,acknow- Jedged to)be of very extensive utility, But from whence is jit procured?—from a far country. Opium, however,much it may beabused,—(and thisis,no solid argument against its great usefulness,: indeed I am. apt to think, that, in all. the ‘more — excruciating pains and. acute diseases,to: which the human frame isiiable, itis of far more jessential, benefit than any other, medicine) ;—-even this commodity we have to proeure — from,a distant country., Mercury and camphire likewise oe eupy alarge space in the apothecary’s shop, Indeed Tam, apt to think,, thai by far the greater partof the medicines at present in; paost- estimation are the produce, of other countries; even wige, in a: medical point of view, 1s in many cases of ithe vy greatestutility. 2 sy) | Sine It may) here be necessary to pPhmvne that, Mr. Protea ae with’ considerable confidence, How. long, ‘an English brick- maker.could support himself upon wine in, place: of porter? I never: meant to say that wine,. as a common beverage to‘a British labourer, was preferable to good English malt liquor. No but my meaning was, that it was, avery useful,and often avery necessary article; that the high, duty was im- politic: and cruel, as depriving all the lower orders, I may al- most add all the middling class of society, of that which in a variety of circumstances is essentially useful, But more of this On Commefce. eth this in another place. After the enumerations! of such. a variety of foreign articles (and many, very many more might be mentioned), absolutely necessary in this country, Am . not justified im’ saying that there is no country which caw produce all that is necessary for the comfort, health, pro- tection, and security of its inhabitants? Or, in other words,—- By having a reciprocal intercourse with other couniries, we make our security more strong, we increase. the necessaries ef life, we enlarge our.comforts, we multiply our pleasures, We procure more means of preserving health and of mitiga- ting pain. But Mr. Lapis brings forth another argument, siials if founded on facts, would certainly have great weight, (viz) That if any country did not produce all that was necessary for the health, comfort, &c., of the inhabitants, such coun- try would be deserted, or no inhabitant would reside in such a situation. Now I cannot admit the truth of this observa- tion; and to prove the contrary, I will not draw the atten- tion of your readers to the barren wilds of Lapland,. or the- mountainous forests of Norway, or some more distant countries.—I will confine my observations nearer home, where the facts } mention can be more easily ascertained. Let those who have not visited the Shetland Islands, only read the accounts given by every traveller. The inhabitants, with afew exceptions, are in astate of inconceivable wretch- edness ; they every year are dependent on forciga supplies for meal, and the distress which they often suffer, for want of this article is great in the extreme; they cannot be said to have any one necessary article of life in plenty except, fish. The making of kelp is the staple manufactory ; ard it is principally with these two articles, fish and kelp, that they procure, as far as they can, a few, and hut a very few, of the most common necessaries of life. Yet Shetland ts not de- serted, its inhabitants are as much attached to the place in which they live as the people who are placed in far more favoured situations. Some may, however, suppose that thig proceeds from: their knowing no better, and being, from their insular situation, cut off from any intercourse with the ‘main Jand.- I will not at present stop to answer this objec- 8 tion, 272 On Commerce. tion, (which might easily be done,) but pass on to the Highlands efSadtlaad. This is not a smal] spot @étached from ses rest of the world, but a large district above 200 miles in Jength, besides the very numerous islands which stretch along the west and northern shores of Scotland, and some ~ of them of very considerable extent :—the island of Lewis is 50 miles long and 30 broad ; Sky is not much inferior 3 and Mull is a large island. The general appearance of the main land, as well as the islands, is.a constant succession of rocks and mountains ; the lower grounds are very much covered with black peat, or moss and heath, which in Scotland is called heather: the inhabitants, with a very few exceptions, live in huts (for houses they cannot be called) without either window or chimney. I will not stop to enu- merate the many distresses to which they are liable; suffice it to say, the privations they suffer are often great in the ex- treme, yet their attachment to the soil is stronger than that of any people T have ever had intercourse with: nothing but force or the most pressing wants will inducea Highlander to leave his country. Nor can his ignorance of more pleasant and much more comfortable situations be argued as the cause of his attachment :—the whole eastern coast of Scot- Jand is in a state of very considerable improvement; the inns on all the principal roads are good ; agriculture is in a state of great forwardness. It is, however, needless here to give a svantaealde description of the country, any further than to point out that the difference between the eastern and western coasts of Scotland is great beyond all conception, but to those who have visited both districts : as the one runs close parallel to the other, the Highlander has constant op- portunities of seeing those more favoured situations; yet he prefers his bleak mountains and-‘smoky hut, to the fine eul- tivated fields and comfortable houses of the Low Countries. Upon the whole, as far as I have experienced, as well as from the information of others, I am clearly of opinion, that the habitants of the more barren parts of this world are more attached to their situation than the people who live where Nature is much more bountiful. I will not at present attempt to account for this propensity; I only state the fact as On the Cure of Hydrophobia in Spain. 273 as ] have found it: at the same time it has often excited my surprise, and engrossed much of my attention. To answer the. remaining objections of your very candid. and agreeable correspondent, and to properly illustrate the remaining parts of my former Essay, would require more time than I can at present spare from my other avocations. Should this merit a place in your very useful and instructive Magazine, you will hear again from, Sir, your most humble seryant, Berwick, Be: JAMES GRAHAMs November, 1808,_ ——~— XL. On the Means employed in Spain for the Cure of Ey ydropholia. ae. To Mr. Tilloch. My. present object is to call the attention of our medical gentlemen toa remedy, which, it is said, has been tried-in Spain with success. This remedy is given by Fisher, in his Picture of Valentia, on the authority of Cavanilles ; and as the whole chapter on the subject is curious, I shall tran- scribe it: *« The inhabitants of the district af Hoya de Castalla, in the southern part of the province (of Valentia), possess an excellent remedy against the bite of the viper; Sena of the sea holly (En ‘yngium campesire), viper’s bugloss (Echium vulgare), madwort (Alyssum spinosum), aud Ge. tan balm (Melissa cretica*), in the following manner : “«¢ The plants are taken when they are beginning to run to seed, and dried in the shade till all their humidity is eva- porated. On this, each is pounded separately, the powder is _ passed through a hair sieve, mixed in equal parts, and put away in well-corked bottles. It is to be observed, that none of the roots must be employed except those of the sea- holly, which possess very great strength. \ * Under this name the plant is described by some botanists, and among the rest by Lamarck; but Cavanilles proves, from thestructure of the calyx ii and other circumstances, that it is properly the Nepeta marifolia. See Anales de Ciencas Naturales, 8vo, Madrid 1808, No. v, p. 192. Vol. 32. No, 127, Dec. 1808. S ‘© With 274 On the Means employed in Spawn «“With respect to the use of this remedy, it is indispensa= _ bly necessary that it should be administered immediately after the infliction-of the wound. The common dose for a man’ is one scruple, for a dog a drachm, and the vehicle used for both is wine or water. No particular diet need be observed, only the powder must, be taken morning and evening for nine days successively. <‘ From time immemorial the inhabitants of this district have made use of this powder as a specific for the bite of : vipers with universal success, till at length the celebrated Cavanilles resolved to try its effects against the bite of mad dogs. He lost no time in communicating his ideas to the physicians and medical men in the province, and had the satisfaction to see that his philanthropic views were produc- tive of the happiest results. “© Thus, for instance, at the farm de los Puchols, in the district of the little town of Sierra den Garceran, a man of sixty named Miguel Puig, and aboy twelve years old named Vito Sorella, were in January 1796 bitten, the one on the hand, the other on the cheek, in such a manner that both Jost a considerable quantity of blood. The physician of the place, Don Bias Sales, was not sent for till three days after the accident: he nevertheless resolved to try the powder, which produced effects that surpassed his expectation. «In fact, the two patients perfectly recovered of the bites, without manifesting the slightest symptoms of hydrophobia, till the present time 1802, and during an interval of six years not the least alteration has been observed in their health. The actual madness of the dog seems to have been fully proved; for several goats and sheep which were like- wise bitten by him died :n 40 days, with all the signs of the most complete hydrophobia. _ © In 1799, at the village of Tornesa, in the district of the same town, a man of fifty-five named Francisco Baset, his daughter Manuela Baset aged twenty-three, and another man named Joaquin Fauro, were bttten, the two former on the hand, and the latter on the middle finger. Baset and his dauvhter immediately applied to Don Thomas Sabater, the surgeon of their village, who furnished them with pow- ders for the Cure of Hydrophobia, 275 ders sufficient for nine days. On the contrary, Fauro, who lived at another village, looked upon his wound as a mere trifle, and took no further notice of it. <* What was the consequence? Baset and his daughter were perfectly cured, and. have for these three years expes rienced not the least alteration in their health; whereas the unfortunate Fauro died sixty days after the accident, with all the symptoms of the most confirmed hydrophobias ** Another dog in Sierra den Garceran had bitten severat other dogs, pigs, &c. The powder was administered ta some of them for eleven successive days; and till the present moment, during the space of nearly two years, no ill conse- quence whatever has been observed. All the animals to whoin the powder was not given died raving mad | in’ 25 days. “ One dog to which it was found a STOTE: to administer more than ats doses, did not go mad, but fell into a kind of lethargy, and refused to eat; till at length he died on the sixteenth day, but without any of the. symptoms of actual hy drophobia. *¢ So much for the experiments, with a remedy, which, as far as I know, has never been included among the six or seven medicines for preventing the consequences of the bite of mad dogs. It seems, however, to be so much the more deserving of the attention of the physicians of every country, as its efficacy against the venom of the viper is fully con- firmed by the experience of ages. s¢ At the moment these sheets are going to press, I find from the Spanish Journals, that this Us has likewise been tried at Madrid with complete success.” In its present state, all that can be done, is to express a sincere wish that it may be found to answer the desired effect ; and I remain, Sir, yours, &c.’ | ers be 39 XLI. A XLI. A Description of the Apparatus by which. the French Experiment on the Decomposition of Potash has been ead at the Royal Institution * i ‘Dats apparatus {see Plate VII.) consists of a common gun-barrel curved, to which there is adapted an iron tube of the: ‘gapacity of two cubic inches for the potash. At the bottom of this tube is a very small hole, through which the potash gradually flows. In this experiment, the iron turnings are first heated to whiteness ; the potash 1 is then slowly fused, and flows on the turnings, where it is decomposéd, and its base is found condensed near the other extremity of the barrel. The proportions from which the best results have been obtained, are about 2} parts of iron turnings, to 14 parts of potash. In order to the complete success of this experiment, some precautions are necessary. The whole of the apparatus, should be perfectly dry, clean, and impervious to air; the turnings free irom oxidation, and the potash very dry; which Jast is effected by heating nearly to redness. Pure or cry- stallized potash in its usual state of dryness contains a suf- ficient quantity of water to occasion tlie failure of the expe- riment. The tube containing the potash should be surround- ed by ice until the turnings are white-hot; and that part of the barrel where the potassium sublimes, should also be kept cool during the whole of the process. The barrel must be carefully Inted. It is proper to examine the lute after it has been exposed to ared heat, in order to repair any cracks which the fire may have oceasioned. A tube of safety with a little mercury or naphtha should be cemented to the bar- rel, to prevent the communication of the external air. At the commencement of the decomposition, hydrogen gas is evolved, and continues to come over during the whole of the process. Towards the end of the experiment a very * For this communication, which will prove highly acceptable to many of our readers, we are indebted to Mr. E, Davy, a cousin of the professor, and a very promising young = intense _ Description of an Apparatus, Be. 277 intense heat should be continued for some minutes to drive off the last portions of: potasstum which adhere to the turn- ings with great obstinacy. _ Explanation of the Plate. A The iron tube containing the potash. B The stopper, ground air-tight. C The-central situation of the iron turnings. D The furnace. E_ The tube of safety. F The pipe of the bellows. XLII. Description of an Apparatus for the Analysis of the Compound Inflammalle Gases by Slow Combustion ; with Experiments on the Gas from Coal, explaining its Application. By Witt1AM Henry, M. D. Vice-Pres. of the Lit. and Phil. Society, and Physician to the In- firmary, at Manchester. Communicated by WH. Davy, Esq. Sec. R.S.* pone sf HE aériform compounds of hydrogen and carbon, which were already entitled to accurate investigation, as objects of scientific research, have derived an additional claim to the attention of the chemist, from their application to an import- ant ceconomical purpose, described in a late commiunica- tion to the Royal Society +. Yet there is, perhaps, no part of chemistry, the investigation of which is beset with greater difficulty, or with more numerous sources of error; inso- much, that the actual state of the science enables us to at- tain scarcely more than approximations to the truth, and de- grees of probability of greater or less amount. It was the object of the experiments, which are described in the follow- ing pages, rather to remove some of-the obstacles, which present themselves to a successful inquiry into the nature of these bodies, than to acquire such facts, as may enable the * From Philosophical Transactions for 1808. Part II. + See Mr, Murdoch’s paper, p. 124.; and Phil. Mag. p, 118—119 of this volume. : $3 chemical 278 Description of an Apparatus for the . chemical philosopher to decide the controverted question re- specting their composition. Results, sufficiently multipli- ed and precise for this purpose, would require a larger ap- propriation of time, than I have the prospect of being’ able. to bestow ; and I-can ouly, on the present occasion, offer an example of the method in which it appears to-me that the analysis of this class of substances wil} be most successfully | attempted. PRK When a vegetable substanee, composed (as may be as- sumed ig simplify the statement) of oxygen, hydrogen, and earbon,.united in the form of.a ternary compound, is sub- mitted to distillation, at a temperature not below that of ig- nition, the equilibrium of affinities, which constituted the triple combination, is destroyed ; and the elements, com- posing it, are united ina new manner. Those, which are disposed to enter into permanently elastic combinations, escape in the state of gas. The carbon, uniting with oxy- gen, either composes carbonic acid gas, or, stopping short of that degree of oxygenation which is essential to change. it into an acid, is converted into carbonic oxide.) The hy- drogen, combining with a portion of carbon, constitutes a binary compound of those two ingredients, forming either what has been called carlureted hydrogen gas, or super- carbureted hydrogen, better known by the: appellation. of olefiant gas. Towards the close of the process, a portion of simple bydrogen gas is also mingled. with the products. Per- haps in no instance is any one of the gases, which have been enumerated, obtained perfectly pure, by the distillation of a vegetable substance. The aériform fluids, which are thus ‘generated, 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 circumstances. It becomes an interesting question, whether these gases, so much diversified in their physical and chemical: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, and 2 eo 3 a ‘ Analysis of the compound inflammalbie Gases. 279 of composing ternary compounds of oxygen, hydrogen, and carbon, or varieties! of oxy-carbureted hydrogen. 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 evidence, | may be permitted, in explaining the following experiments, to assume that theory which appears to me most probable; viz. that the aériform products of the distillation of vegetable substances, are mixe tures of carbonic acid, carbonic oxide, olefiant, carbureted hydrogen, and simple hydrogen ‘gases ; or of two or more of these in various proportions. The analysis of these compound gases has biaherta been attempted solely by their rapid es nbuceen with oxygen gas, in the following manner: a mixture of the inflam- mable gas with oxygen gas in known proportions, is ad- mitted 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 11 sustains a second diminution of bulk 3 and the amount of this denotes the quantity of carbonic acid, formed by the combustion. The quantity of nitrogen gas, in the oxygen employed, as well as in the residue left by potash, being de- termined by a fit eudiometrical test, it is easy to infer what quantity of oxygen has been absorbed by the detonation, And as it is proved that oxygen gas sustains no change of bulk by conversion into carbonic acid, we may conclude that, after deducting from the volume of. oxygen gas expended, that of the carbonic acid which has been formed, the remaining number shows how much oxygen has been employed in the. saturation of hydrogen. If, for example, 100 measures of carbureted hydrogen consume 200 of oxygen gas, and give 100 of carbonic acid,-it follows, that the carbonic acid holds in'combfhation 100 measures of the oxygen gas consumed ; and that the remaining hundred have been applied to the sa- turation of hydrogen. In this estimate it is assumed, that the carbon has acquired, by combustion, the whole of the oxygen necessary for its acidification, and that no part of it existed pre- viously in the.state of carbonic oxide; a proposition, in many cases, perhaps, very far from being consistent with the truth. $4 i Ehis - 280 Description of an Apparatus for the This, however, admits of being decided by an accurate coms parison between the weight of the gases consumed and that of the products. For the purpose of 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 exhibits the — results of the combustion of the few gases that appear en- titled to be considered as distinct species. They are deduced _ from the experiments of Mr. Cruikshank and Mr. Dalton. 100 measures. Kind of Gas, Sp. Grav. |Take meas.|Givecarb-| Are dimin. (air=1000.)jof oxygen.| acid. | by firing. Olefiant - ~ - 909 300 ~ 200 200 Carbonized hydrogen, from 600 200 100 200 stagnant water, 4 Carbonic oxide -— - : 967 45 90 55 Hydrogen gas - - - 84 50 154 The inflammability of the compound gases, and their fit- ness for the purpose of affording light, are directly propor- tionate to the quantity of oxygen required for their saturation. The olefiant gas, therefore, burns with the greatest brilliancy; . carbureted hydrogen gas, though inferior, affords a dense and . compact flame; but the carbonic oxide and hydrogen gas are ; entirely unfit to be employed as the means of artificial rlumi- nation. In the execution of aseries of experiments on the com- pound combustible gases, which are described in the 11th voluine of Mr. Nicholson’s Philosophical Journal, I had rea- ‘son 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 respect to some, it was evident that the full proportion of: their carbonaceous ingredient was not oxygenized, in con- sequence of the precjpitation of charcoal in the act of de- tonation. The quantities also, that can. be submitted in this way to experiment, are extremely minute ; and the in- flammation of highly combustible gases is attendéd, ,as.1. 3 op, aie Analysis of the compound inflammable Gases. 281 have more than once experienced, with considerable danger from the bursting of the glass tubes. It was desirable, there- fore, 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 cylinders, or air receivers*, J} and 00 (PI.VI.), of which the larger one is intended to contain oxygen gas, and the smaller one, the inflammable gas submitted to experiment. They are con- nected by a bent glass tube ss, the diameter of which should not be less than 54; of an inch, to the upper extremity of which is cemented an iron burner, ¢, the orifice of which is about 4, of an inch, while to the lower end a socket is fixed, on which may be occasionally screwed the cock r. The receiver 0 0 is contained in a larger glass jar 7, and is closed at the top by a brass cap p, and stop cock g. The oxygen gas receiver is, also, closed by a brass cap e and cock f, the lower orifice of which is tapped internally, for the purpose of receiving a small screw at the end of the copper wite g. This wire is in two parts, each of which screws into a moveable 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 2 ois partly filled with the combustible gas; and is secured by wedges of cork vv, in the jaram, the level of the water in the latter being reculated by opening the cock a or z. The bent pipe ss, 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 afew inches above the surface of the water. The receiver b & detached from the situation in which it 1s represented in the drawing, is then exhausted by an air pump; and, being Giled with oxygen gas, is transferred (its mouth heing closed during the act of removal with a piece of leather) to the cistern @, and quickly inverted over the burner f. By a * Lam indebted to Mr. H. Creighton, of Soho, not only for a drawing of the apparatus, but for much valuable assistance inthe performance of the ex- periments 5 ‘ little ° 282 Description of an Apparatus for the Nittle practice, this may be done with the admission of very. hittle common air. A transferring vessel-is then screwed upon the cock f 3 and a portion of oxygen gas removed for eudiometrical examination. To allow room for the ex- pansion of the oxygen gas, the water is raised by a syphon to a proper height within the reeeiver J, as appears in the | drawing. The apparatus being thus disposed, the cock fis connect- ed by the chain A, with the prime conductor of an electrical machine ; and arapid 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 g and r being now opened, the stream of gas is kindled ; and in order to prevent the flame from playing upon the wire, the jar 22 1s moved a lit-_ tle nearer to the cistern @, which brings the point of the burner into the axis of the receiver. At the same time, by opening the cock x, water falls into the jar 2, and finds its way into the receiver, through two small holes.ww drilled © near its mouth. The combustion continues, until either the whole of. the inflammable gas is consumed, or till the cocks g andr are shut. The wedgesvv are removed; the receiver oo un- screwed; and the bent tube removed from its place. It is at this moment that the cock 7 is useful, by preventing the escape of the gas from the receiver J through the tubes ss. The upper part of the receiver is cooled by the application of a wet sponge. Without waiting, however, till the gas has attained the temperature of the atmcsphere, avery small and sensible thermometer is introduced into it ; and the height of the mercury is noted, as soon as it becomes. stationary: The volume of the residuary gas is then observed, and is re« duced by calculation, to the bulk which it would occupy at 60° of Fahrenheit. Either the whole, or an aliquot part of it, is removed by a transferring vessel, screwed upon the cock f, to a mercurial cistern, where the proportion of car-_ bonic acia is determined by liquid potash. The proportions of oxygen and nitrogen gases, in the unabsorbed residue, are learned by agitation with sulphuret of lime, observing the precautions which have been stated by De Marti.. The »res, siduary Analysis of ihe compound inflammable Gases. 283 siduary oxygen being deducted from the quantity at the out- set of the experiment, shows how much oxygen has been eX- pended in the combustion of the iihininaile gas. [t is scarcely necessary to observe, that the gases are carefully re- duced, ét each stage of the operation, to a mean temperature and pressure, (60° of the thermometer, and 30 inches of the barometer) *. The process of combustion, as thus stated in general terms, appears sufficiently simple. It is often, however, ren- dered complicated by the imperfect combustion of the in- 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 oxygen gas remaining in the receiver 4. I am unacquainted with any method of entirely obviating this difficulty ; but its amount may be diminished by an attention to certain precautions. With this view, the pressure upon the gas, contained in the receiver oo, should, on first open- ing the cocks g and7, be no more than is sufficient for its gentle expulsion through the tube ss. When, however, the stream is once kindled, the larger the flame, and the more | active the combustion, within certain limits, the more com- pletely is the gas consumed. It is necessary, also, to stop the combustion, before it 1s rendered languid by the admix- ture of carbonic’ acid with the gas in the receiver 4, and by the diminished purity of the oxygen gas. If this be not attended to, a laree proportion of the: inflammable gas to- wards the close of ‘the process, makes its escape unaltered into the receiver 4. In general Ihave found, that setting out with oxygen gas ef equal purity, the more combustible the inflam- mable gas submitted to experiment, the more complete is its decomposition by slow combustion. The apparatus, there- fore, is better adapted to the analysis of olefiant gas, of car- bureted hydrogen gas, or of mixtures of these two, than of carbonic oxide, or any gas of which that oxide forms a large proportion. * The rules observed in these calculations, are stated in my Epitome of Chemistry, 5th edition, p. 441. The 284 - Description of an Apparatus for the The. inflammable gas, which has found its way into the receiver J, is always present in too minute a quantity to compose, with the residuary oxygen, after the removal of the carbonic acid,.a mixture capable of being inflamed by the electric spark. To ascertain its precise quantity, it © is necessary to have recourse to another operation. After. trying, -eudiometric ally, the quality of an aliquot part of ~ the gas in the receiver J, let a similar aliquot part be de- prived of its carbonic acid, and then mixed with a portion of pure hydrogen gas, not exceeding one-third or one- fourth the estimated bulk of the oxygen which it contains. Detonate the mixture, and observe the amount of the di- minuuion after the explosion; the products of the com- bustion ; and the quantity of oxygen gas consumed. After subtracting, from the total eeenganes of oxygen, half the bulk of the added hydrogen gas, the remaining number shows how much oxygen has been absorbed by the combustible gas contained in the residue. By the rule of proportion, it may be determined, how much carbonic acid would have been produced, by the oxygenation-of the whole of ‘the combustible gas, and what quantity of oxygen it would have saturated. The most obvious objection to this method of analysing the compound gases 1s, that the real proportion of the pro- ducts, resulting from their combustion, may ~perhaps be 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 source of error too trivial to be deserving of consideration 3 and that the proportion of carbonic acid, thus generat- ed, exceeds what is composed by the rapid, combustion of the same gas over mercury. When the operator has ac~ quired sufficient dexterity, the interval of time, between the completion 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 car- bonic acid constitutes only a small part of the residue ; and is, for that reason, very little acted on by water, conformable - toa principle which I have explained in the Philosophical Trans- \ / Analysis of the compound inflammable Gases. 285 Transactions for 1803, p. 274. I believe, therefore, that with an attention to those observances, which are required in ali delicate experiments on gases, and to the changing cir cumstances of temperature and pressure, this apparatus is fully adequate to the purpose for which itis mtended. It will be easy, however, for those who have the command ofa suf- ficient quantity of mercury, to adapt the apparatus to that fluid. As an exemplification of the method of using it, in the sim- plest possible case, I shall state the results of the combustion of hydrogen gas. At the outset of the experiment, there was contained i in the receiver 00, a quantity of hydrogen gas, equal, when reduced to a mean temperature and pressure, to 15°8 cubic inches. Of these, there remained unconsumed | 2°5 Hydrogen gas burned - = = 13°3 In the receiver ) were 49 cubic inches of oxygen gas, con-. sisting of - - - = + 33°5 oxygen, 15°35 nitrogen, At the close of the mipasoca } 7°25 \ there remained, inl, 43°5c.4 16°25 composed of Cubic inches of oxygen gas consumed But estimating from the first diminution (viz. 49-43: 5) only 5°5 cubic inches of oxygen would appear to have been absorbed; and the nitrogen gas, by eudiomctrical experi- ments, would seem to have been increased 0°75 of an inch. As the hydrogen gas, however, had been prepared from zinc and sulphuric acid with extreme caution, and did not contain an appreciable quantity of common air, no such addition of nitrogen could have taken place. The apparent oY ee then, may be fairly imputed to the escape of 0°75. of an inch of hydrogen gas, which is to he 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=19°55. The true consumption, also, of oxygen gas was 5°50-40°75 = 6°25, or pretty exactly, as it ought to be, half the bulk of the hydrogen gas, which was actually burned, 6°25. An 286 Description of an Apparatus for the An example of the analysis of a highly combustible species of elastic fluid is furnished by the following experiments on the olefiant gas, obtained from alcohol and sulphuric acid. Of this gas 100 cubicinches, at a mean of the barometer and thermometer, were equal to 30 troy grains ; hence its specific gravity was. 967. In the receiver 90, were contained of this gas 6°3 cub. in. , Residue - - - - - 2 { Gas consumed - - = - 4:3 In the receiver /, were 43°4 inches of oxygen gas. After the combustion, there remained 38*2 cubic inches of mixed gases, 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 ind, not ab- sorbable by sulphuret of lime, so far from having been in- creased, was found to have sustained a trifling diminu- tion. The oxygen gas, which was consumed, amounted to 13°8 cubic inches. Reducing these results to centesi- mal proportion, 100 cubic inches of this gas would give 200 of carbonic acid, and absorb 325 of oxygen gas. This ex- periment agrees with Mr. Dalton’s, as to the proportion of carbonic acid from the combustion of olefiant gas, but assigns a larger consumption of oxygen. It may be ob- served, however, that the specific gravity of the gas, which I employed, exceeded a Jittle the statement of the Dutch chemists, who found its specific gravity to be 909, common air being 1000. Having satisfied myself, by repeated experiments, of the accuracy ak the results which may be thus obtained, I pro- ceeded to the combustion of the gases from a variety of ve- - getable substances, and especially from those which it seem-. ed probable might become ceconomical sources of light. In the present memoir, I shall describe those only, which were made on coal and afew similar substances, pape the rest for a future communication. Gas from Cannel Coal. ‘This was received in two separate portions. -f the first xs pro- ‘ / Analysis of the compound inflammable Gases. 287 product, 100 cubic inches, corrected to a mean temperature and pressure, weighed 24°98 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 oC 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 hydrogen gas ; detonating the mixture by the electric spark ; and proceeding as already directed. The two first lines contain the minutes of actual experiments ; _the third and fourth these results reduced to centesimal pro- portion. i y Carb.acid/Ox. con- Sp. bCnb. jn, |O% £25 Carb. acid}formed by |,umed by] Votal ox.} Total car-| p. ‘{Cub. in. |. ea : aC legis icaci Grav. | burned, (Coms2™- zenerat- {second econd — |consum-|bonicacid ed. ed. combus- |eombus- fed. farmed, tion. ‘ion. 783 eS 16°5 8:3 eo) 0:9 17:4 10°2 335 98 Oe 45 10) 10) Ore: 4:3 783 | 100 222 EUS :7 2°6 12 234 4139-7 335 | 100 96 49 0 10) 96 49 The early product of the gas from cannel coal, before being washed with lime-water or caustic potash, 1s a mixture of several different gases, viz. carbonic acid, sulphureted hydrogen, olcfiant, and a fourth, which is either a gas swe generis, or a mixture of carbureted hydrogen and carbonic oxide, To ascertain the proportion of these gases in any mixture, 1s a problem of some difficulty. drogen and olefiant gases experience, it is well known, an immediate condensation, when mingled with oxy-muriatic acid gas, and in this way they mav be separated from carbonic Ayain, sulphureted hvdrogen and carbonic acid are absorbed by liquid potash, which has no action on olefiant If, therefore, two equal portions of the gas from coal be mixed with oxy-muriatic gas, the one in its recent 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 at- acid. gas. Sulphureted hy- talm 258 “Description of an Apparatus for the pays tain an approximation, at Jeast to the proportions in which carbonic acid, olefiant, and sulphureted hydrogen gas are’ mingled with the aériform product of coal. «The rule may ‘be stated as follows : To a measured quantity of oxy-muria-' tie 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 oxy-muriatie acid as before. The second diminution, thus effected «by oxy- muriatic gas, divided by 2*2,-gives the proportion of ole- fiant gas. Deduct this absorption from the first, and, di- vidiig the remainder by 1:8, we obtain the quantity of sul- phureted hydrogen. Lastly, to know the quantity of car- bonic acid gas, subtract, from the diminution effected by . potash, the amount of the sulphureted hydrogen gas. An ex- ample, taken from actual experiment, will best Heh the application of this rule. : One hundred measures of the first product of eet from cannel coal lost, by agitation with liquid potash, 97 measures. The remainder, being mingled with one-fourth , its bulk of oxy-muriatic 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 unwashed gas sustained, by admixture with oxy-muria- tic 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, gives 5'3 for the proportion of suipheraed hydrogen gas. aad the diminution by potash (= 9:7) — ' 5*3 gives 4°4 for the proportion of carbonie acid gas. Hence 100 measures of the first product of gas from cannel coal contain, 1, Of inflammable gas, not affected by the foregoing agents 854 gq. Of s sulphureted nysrogen EAS eT 3. Of olefiant gas - errr 4, Of carbonic acid A a oie ira Lad 7 100 The Analysis of the compound inflammable Gases. 289 The proportion of common air, in the foregoing speci- men of gas, and in all cases when care was taken to ex- clude it, was too small.to deserve being taken into the ac- count, not appearing, by the test of nitrous gas, to exceed 1 per cent. The following table exhibits the composition of gas from various kinds of coal. In the last column, under the term inflammable gas, is comprehended that portion, which is neither suddenly condensed by cxy-muriatic acid 2as, 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 of doubt. TABLET: Nalece One hundred measures consis'24 » £ |. Kind of Coal. Bere ah ; Sanaa P : product. |Sul.Hydr.| Carb. acid. jebant. Wiiiain. fe 1 5°3 : go) hil ega= } Wigan cannel. ; 2 0: hs a aes Wednesbury, 1 4:9 8:4 (0) 91-7 Staffordshire. } 2 0: 28 6) 97-2 Newcastle on 5 1 29 2:8 27 91-6 | . Tyne. ¢ 2 2-2 IGF fe) 961 ne Soied | S OE Atak as i) 94:3 Pima ha lee boa ale.) | ae A Bg | 0 1-4 9 93-6 fin aes 1 2 1 94 ee near } 9 1-4 7 0 96-9 2 3 (0) 2 10) 98- f 1 33 32 Piss 91 Pe 1| 2 2 11 0 96:9 | Black Mine, near | neta 2 1 oO 97 Manchester. (| 4 Os 1-2 0 93:3 My 0 1-2 0 98 8 ie 6 10) (0) (6) 100 (j 1 1 C7 19) 97°3 ; ey 0 atlas O 98:3 Merthyr, Glamor- | 3 oO 1-6 (@) 98:4 ganshire. 4 4 0 ir plos, co) 985 l 5 O 1 (@) 99 6 0) O (0) 100 Native coal tar. — | 13 6 15 66 Caoutchouc. — 6) 49 17 78:1 After separating the sulphureted hydrogen and carbonic acid gases by agitation with liquid. potash, the residue, con- sisting of the inflammable gas mixed with the proportion . Vol, 32. No. 127. Dec. 1808. Ai pe) 290 Description of an Apparatus for the \ 7 Pau. . . of olefiant gas produced aiong with it, was submitted to, combustion. ‘Phe jollowing table shows the average re- sults of a number of these experiments. . TABLE -II. SS a 100 cubic inch. - r No. of Weight of papeyetelaa a Kind of Coal. |thepro-} 100 cubic inches |?P* $°2"-lconsumelgive car.| ~ duct. |(Ther.60°% Bar. 30.) (ait 1000) ox. gas. | acid. Wigan cannel 4 : Ze Cis. ee Fe eae 4 2 10°4 $35 96 49 ~ a “5 Wednesbury coal. { ; Fah 2 é ie | se 4 Newcastle on ° 1 19°3 622 > |. °190 | 100 Tyne. 1 2 9:8. 316 86 45 : oe A a 1 19°6 32 195 | 98 AE we abuts, Staf- 2 17°7 570 165 80 ogee ak 3 12°1 390 | 100 | 60 : 1 20°7 670 190 | 100. | Leeds. \ 2 15.) 487 lost by accident. | | -8 9°8 “iin BEG 85 42. { Z 19°4 627 189 67 i}. 2 15 484. | 13% | 65 | Black Mine, Lan- ; 3 11‘3 364 1CO 50 cashire. 1 4 10 322 990 47 5 9°5 307 85 45 | tee 80 | 40 (; 1 12 387 17 62 | | 2 9°5 $07 90 47 ' 3 8 261 45 89 Merthyr. ; | 4 ei 190 “es et! 5 58 187 57 96 Ling 5:5 177 50 | 20 Coal tar. — 24:2 780 935 150 « aoutchouc. -- — — 204 121s | An attentive examination of the results, contained in both | the tables, suggests the following general remarks. 1. The olcfiant gas is a very sparing product of the distil- lation of pit-coal. It is found only.in the first portions, and even of these it does not compose more than 5 percent. Its >. quantity, however, is very much influenced by the tempera- ture employed. This remark, indeed, imay be extended to all the aériform products of coal ; insomuch that from 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 Coal- brooke-dale tar, and that from Caoufchouc, have a larger pro-! 6 . . portion > _ Analysis of the compound inflammable Gases. 294 portion of olefiant gas,which in them amounts to about one-sixth their bulk. " 2. Sulphureted hy ‘drogen gas is, also, most alumdantly produced at the early stages of the distillation. Its proportion then varies from 1 to 5 per cent. ; and towards the close of the process it disappears entirely. It increases the illu- minating power.of the coal gas ; but is by no means a de- sirable 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 sulpbureted hydrogen is produced, than is discovered among the aéri- form products ; fora part, uniting with the ammonia which is generated at the same moment, forms sulphuret of am- monia, a compound which I have found among the con- densed products. 3. Carbonic acid gas, like the two preceding ones, appears 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 2 gradual diminution of specific gravity and combustibility, from the commencement to the close of the process. This_is best shown by inspecting the results of the experiments on the Black-mineand Merthyr coal gas in Table II. because they were reserved in a greater waaiber 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 bad not been al- lowed to escape, in consequence of the immense quantity which was produced. The specific gravity of the coal gas appears to afford a measure of its fitness for illumination, sufficiently accurate for practical usés 3 but does not bear an exact correspondence to the chemical properties of the gas, as ascertained by combustion. It may be remarked, also, by comparing the two last columns of the second table, that the carbonic acid produced does-not always bear the same pro- portion to the oxygen ld ae Thus the first product of gas from cannel coal combines with 234 measures of oxygen gas; and gives 139°7 of carbonic acid. But the gas from coal ee tar, 292 Description of an Apparatus bos the tar, with only an equal consumption of oxygen, vields 150 measures of carbonic acid. 5. The aériform product of coal does not se. answer to the characters of any one of the combustible gases with which we are acquainted. The first product, however, of the distillation of common pit coal, after being washed with - potash, approaches very nearly in its properties to carbureted hydrogen gas. The gases, which surpass this in specific gra- vity, are mixtures of carbureted hydrogen with olefiant gas, dnd perhaps a small proportion of carbonic oxide. The lighter gases, in addition to carbureted hydrogen, probably | contain a variable proportion of hydrogen gas and a small quantity of carbonic oxide. The extreme levity of some of the products, especially of the gas from Merthyr coal, can- not be explained on any other supposition. 6. The products of the combustion of a cubic foot of coal gas, of medium quality, viz. of the specitic gravity 622, (such - as. the first products fron Newcastle on Tyne coal,) may be stated as follows : Grains. A cubic foot, at_a mean of the barometer and ther- mometer, - s - . - 333°5 By combustion, it vields 817°3 grains of carbonic acid, the carbon in which may be estimated * at. tm ~ - - - - 2337 Grains of hydrogen in a cubic foot of coal gas, - 99°8 But 99°8 grains of hydrogen are equivalent to the satura- tion of 554°9 grains of oxygen, with which they form 654°7 grains of water. Hence the oxygen consumed ought from calculation to be 817°3—233°7=573°61554°9=1128 And the quantity actually consumed appears by experiment to be - ( ae - 1110°3 . Error - = - 17-7 The difference, in this example, between experiment and. calculation is not greater, than, in such delicate processes, * Assuming the carbon to be 286 grains in 100 grains of carbonic acid, as is satisfactorily proved by the experiments of Messrs. Allen and Pepys. may Analysis of the compound inflammable Gases. 293: may always be expected. ‘A part of the deficiency in’ the exygen actually consumed may be ascribed, also, to a small] portion of the inflammable gas being already i in the state of carbonic oxide. Without repeating the particulars of a similar calculation made on gas of inferior quality, I shall annex a comparative statement of the specific gravities and composition of the good and inferior gases. a ne ! i | Weight | Acubic foot | Oxygen gas | Gives | Source of the gas. jofacubic} consists of |consumed by| ———~——\ foot. carb. hydr. | a cubic foot. |Carb.acid. Water. oe | ee. pee coal, -/333°7gr.| 233-7 | 99:8 1110°3 8173 | 621° Ditto, last product, 169°5 | 111°5 | 57°8 560 400 | 384-9 The inferior gas, also, probably contains carbonic oxide ; for the quantity of oxygen 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 oxygen. The quantity of water, which was generated by com- bustion, was not determined experimentally, but is merely estimated. It must be acknowledged that the decomposi- tion of the inflammable gases cannot lead to unques- tionable results, until the proportion of water, produced by their combustion, be also accurately ascertained. With the view of effecting this, I have already spent much time, and employed many contrivances, none of which have satisfactcrily 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 speci- mens of coal, even when taken at similar periods of the di- stillation. The coal from Merthyr in South Wales, which. burns without flame or smoke, yields a gas which contains, in an equal volume, scarcely half as much combustible mat-: ter as the gas from Wigan cannel, This will probably be found to be the case with respect to all coal of similar quae. lity, among which may be reckoned the Kilkenny coal. The most important difference among the varicties of this mi- T3 neral, « 294 An Invention feds preserving the Lives neral, connected with their application as sources of light, consists in the quantity of sulphureted hydrogen gas, which is mixed with their aériform products; and it unfortunately happens that the coal, otherwise best adapted to this pur- pose, vields generally the largest proportion of this offensive gas. The only effectual method of purifying the coal gas” from sulphureted hydrogen, on the large scale 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, Tn the experiments which were made on the products of the distillation of coal, T 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 manufactures than bv limited experi- ments. For the same reason I was not solicitous to mea- sure even the aériform fluids; and on this subject, I be- lieve, more accurate information has been communicated by Mr. Murdoch, than it was in my power to acquire, oe = - = = XLII. Liewtenant Bevv’s Invention for preserving the Lives of Mariners in Cases of Shipwreck*. Posuterry having been recently given to some experiments off the eastern coast of this island, for preserving lives in cases of shipwreck, by means of a rope attached to a shell | thrown from a mortar, the Society of Arts, &c., has thought it incumbent on them to remind the public, that so far bale as the year 1792, a bounty of fifty guineas was given to Mr. John Bell, then serjeant, afterwards lieutenant of the royal | regiment of artillery, for his invention of throwing a rope an shore, by means of a shell from a mortar, on beard the vessel in distress; the particulars of which were published ~ in the tenth volume of the Society’s Transactions, page 204 ; * From Transactions of the Society for the Excouragement of Arts, Manu- i factur es, and Commerce, for 1807. but ‘ of Mariners ih Cases of Shipwreck. ~- 295 but a descriptive engraving having been omitted at that time, it 1s thought expedient to insert it in the present publ. aN with some further particulars then omitied. Medels and drawings of the whole apparatus are reserved in the Society’s repository, for the inspection of the public. - The several trials made before 4 committce of the Society at Woolwich, on the 29th of August 1791, of throwing 4 line on shore on this principle, were as follow: From a boat moored, about 250 yards from shore, the hen was thrown 150 yards on shore, with the rope attached to it; the shell was of cast-iron, filled with lead, it weighed 75 pounds, its diameter eight inches ; ‘thet rope in tethal, was a deep sea-line, of which 160 ae weighed 18 lbs: the angle of the mortar from whence the ane was fired was 45 degrees. By means of the line, Mr. Bell and another man worked themselves on shore upon | his raft of casks ; there were many kinks in the rope, which were with’ ease cleared by Mr. Bell, in which ’ he was much assisted by. his snatch blocks. ie The second trial was repeated ia dimifar’ manner, af with equal success, the shell falling within a few yards of the former place; the gale of wind was brisk, and the water rough. The direction of the shell was nearly from notth to . southi, and the wind blew nearly north- Wester aye 6 In the third trial; the mortar was elevated to 70 pleuiels - : the rope attached to the shell was an inch and half hel rope, of which every 50 yards weighed ‘fourteen pounds and a half; the shell of the kind Foie men tioned : it fell 160 vards from the mortar, and buried itself about two thirds j in the ground ; the line or rope run gut was about 200 yards, and It Fequired the force -of three men to draw the, shell“ out of the ground at that ‘distance. The grommet, in al! these trials, was of white ‘three re rope; and in all the above trials, by mean’ of the ine, two men worked themselves on shore upon the raft: : each charge of powder was fifteen ounces. Se Se A fourth experiment was made by firing, from the same mortar, a grapnel in a wooden case ;_it did Not retain its hold in the ground so well as the shell, but amongst the E T4 crevices 296 An Invention for preserving the Lives - crevices of rocks, or where the vessel i: oes shore, will be useful. : A grapnel of this en may be fined from a common can-, non with an endless rope, running in a pulley or small block fixed thereto, by which a raft. may be successively drawn ta. and from the vessel either by the persons on board the ves- . sel, or those on shore. ° Olservations made by Lieutenant Bell, upon throwing a Line on Shore in case of a Ship being stranded. — Ist. From the proposed construction of the piece of ord- nance, intended to throw the shot and line on shore, I sup- pose it will be between five and six hundred weight. The chamber is to contain one pound of powder, and tke bore to admit a leaden ball of sixty pounds or upwards; the Jength of range, or distance, will depend upon the size of the line made use of; I suppose it will carry a deep sea-line between three and four hundred vards distance. 2d. All ships that have iron ballast, may use this piece asa part of it, and then there would be only the trifling dif- ference of casting so much of the ballast into the form of the piece; the leaden balls may likewise be used as ballast. _ 3d. I am of opinion there are various ways, on board of a ship, that the mortar may be placed in a praper position _ for firing without a carriage expressly made for jt; it may be placed upon a coil of rope, or its trunnions rested upon coins, or any thing else, whereby the muzzle can be raised so high that the groove upon the trunnion appears vertical, "as the piece in that position would be elevated nearly 45 degrees. 4th. As I imagine all ships carry deep sea-lines, on that account I made use of it in the experiments at Woolwich ; but if it should be thought too short for the distance, any other light line may be added to the length of it. 5th. Supposing a ship’s owner to purchase such a piece of ordnance with the leaden balls, and a block carriage ; w dodo not think the whole would amount to more than ten or eleven pounds expense. 6th. Where a ship is driving,’ or unmanageable, near the shore, of Mariners in Cases of Shipwreck. 207 shore, it would be proper to have the piece loaded, the line ~reeled upon hand-spikes or poles, and laid upon the deck ready for firing at any time it might be judged necessary. The hand-spikes or poles, the line is reeled upon, preserve it in an horizontal form; and they are not to be drawn out until. the instant of firing: in this manner the line will de- liver itselt freely. The five water-casks should also be Jer in readiness, by lashing them together, and a seaman’s chest fixed upon the top of them, having part of its ends or sides cut out in order to Jet out such water as may be thrown into it by the’ surf. I dare undertake to land with such a float upon a lee shore any where upon the coast, when it might be deemed unsafe for a hoat to make good its landing. 7th. There is every reason to doatbane. that this conti vance would be very useful at all ports of dificult access both at home and abroad, where ships are liable to strike ground before they enter the harbour, as Shields Bar, and other similar situations, when a line might be thrown over the ship, which might probably be the means of saving both lives and property ; and moreover, if a ship was driven on shore near such a place, the apparatus might easily he re- moved to afford assistance ; and the whole performance 1S sO exceedingly simple, that any person once seeing it done, would not want any further instructions. Joun Bett. Woolwich, Aug. 29, 1791. - ee Some further Observations made ly Lieutenant Bell, upon the Application of the Mortars intended for thr owing a Line on Shore, in case of a Ship being stranded. ~ ist. In trading ships, this piece would answer for making signals of Tee by filling the chamber with powder, and well wadding it, as the report would be heard some miles distance at sea. ~ = ad. Such a gun, being accompanied with a few rounds of round and grape-shop, would defend a ship much better than a longer gun, against any piratical or other hostile inten- tions, 4 298 An Invention for preserving the Lives of Mariners. tions, as, from its shortness, it would be more readily loaded and fired with a larger charge each time. . 3d. Accidents Fain a gun bursting, which may arise from an unskilful person loading with too great a: proportion of powdery, is in this piece effectually guarded against, by the — chamber being constructed to contain but one pound of powder, a quantity which. is only about one-third of the usual charge of a cannon. . 4th. From the small size of such a gun and carriage, it might be kept upon deck, without much inconvenience in working the ship, in order to be ready if necessity required 5 and when the ship ts out at sea, it might’ then be put below? But from the number of. dreadful wrecks, which so fres quently happen along the coast, it certainly would be pra dent to have it always upon deck when within sight of land, and particularly in stormy weather. ' Joun Bett. Woolwich, Sept. 30, 1791. To C. TayLor, M.D. Sec. - Reference to the Engraving of Lieutenant Bell’s Method of throwing a Rope on Shore, from a stranded Vessel. Plate VILI. a, Fig. 2. Represents the mortar on its carriage; b, the shell shown within the mortar by dotted ]mes ; c, the grom-_ met, or double rope, which connects the shell and line ; dd, the line to be thrown on shore, now ready wound on the poles or hand-spikes, pp, and which are to be withdrawn when the mortar is fired, Fig. 3. Is a separate view of the shell, with the grommet and end of the line attached thereto, explained by the same letters. | Fig. 4. Shows another invention, suggested instead of a shell, and to be fired from a common cannon, in which e is an iron pin; f, an iron collar and rope sliding upon it; g, an iron ring which turns upon two pins in the collar; & is the grommet or double rope, attached, to the ring, to which the-line to be thrown on shore is fastened. This plan may On the Origin and Office of the Allurnum of Trees. 299 may be used where people are on shore, to assist when a line is thrown. Fig. 5. Shows a grapnel which may also be fired from a common cannon; the collar slides along it in the same man- ner as that in fig. 4, to allow the head of the pin to go down to the wadding within the cannon; 27, are two pins on which the ring &, is moveable; d, the block or pulley fast- ened to the ring; m, the endless or double line running through it. This method may be used with great advantage, where a ship is stranded near the shore ; but where a mortar is on | board, the use of the shell and line is the most certain. Fig. 6. Shows the method of forming a raft, by lashing together with ropes, five empty water-casks helonging to the ship. Fig. 7. Represenis the raft ready for use ; the apparatus n to hold the person upon it, is made from a seaman’s chest with holes cut in the sides of it, to allow the person within it firmer hold, and to Jet out the water that may be thrown into it from the waves; 00, are two pulleys attached to, the ends of the chest, and through which the line is to run; the raft is to be ballasted underneath, to prevent it from up- setting. The whole apparatus is so arranged as to be inclosed in a small box, as may be seen by a reference to that in the Society’s possession. ; MLIV. On the Origin and Office of the Alburnum of Trees. Ina Letter from T. A. Knicut, Esq., F.R.S., to Sir JosEPpH Banxs, Bart. K.B. P.R.S.* MY DEAR SIR, ly my Jast communication I endeavoured to prove that the bark of trees is not subsequently transmuted into alburnum; and if the statements that I have there given be correct, they are, I conceive. decisive on the point for which I con- tended: and if the bark be not converted into alburnum, the experimeuts of Dubamel, and subsequent. naturalists, * From Philosophical Transactions for 1808. Part IL and 00 On the Origin: and Office of. the Albzw urnum m of T. reas. and those of which I hone given an beeoude in former me- moirs, afford sufficient evidence that the bark deposits. the: alburnous matter.. If the succulent shoot of a horse ches- nut, or other tree, ‘be examined, at successive periods in the spring, it will be seen that the alburnum is deposited, and- iis tubes arranged, in ridges beneath .the cortical vessels ; and the number of tnese ridges, at the base of each leaf, will be found to correspond accurately with the number of aper- tures through which the vessels pass from the leaf-stalks into the interior bark, the alburnous matter being apparently deposited (as I have endeavoured to prove in former me- moirs) by a fluid which descends ns the leaves, and subs, sequently secretes through the bark *. T shall therefore ven- ture to conclude that it is thus Sees and shall proceed to inquire into the origin and office of the alburnous tubes. The position and direction of these tubes have induced al-_ most all naturalists to consider them as the passages through which the sap ascends; and at their first formation, when the substance which surrounds them 1s still soft and sucen- lent, they are always filled with the fluid, which bas appa- rently secreted from the bark, They appear to be formed in. the soft cellular mass, which becomes the future alburnum, as receptacles of this fluid, to which they may either afford a passage upwards, or simply retain it as reservoirs, till ab- sorbed, and carried off, by the surrounding. cellular sub- stance. 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. e Many different hypotheses have been offered by naturalists to account for the ferce with which the sap ascends in the spring; Gf these hypotheses two only appear in any degree adequate to the effects produced. Saussure, jun., 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 have suggested that the expansion and contraction of the compressed cellular, or laminated substance (the tissu cel- * Philosophical Transactions for 1801, p. 336. lulaire 6 On the Origin and Office of the Allurnum of Trees. 301 lulaire of Duhamel and Mirbel) which expands and contracts . with change of temperature* after the tree has ceased to live, might produce similar efiects by occasioning nearly a_ similar motion and compression of the tubes, the coats of which are, I believe, universally admitted not to ‘be mem- branous. But both these hypotheses are inconsistent with the facts that I have now the pleasure to communicate to you. ! , Selecting parts of the stems of young trees, from which annual branches had sprung in the preceding year, J ascer- tained by injecting coloured infusions into the stems, t hrouch the annual shoots, that the tubes which descended from the Jatter, were, at their bases, confined to that side of the stem from which they sprang, and to the external annual laver of wood. Deep incisious were then made into the stems of other trees immediately beneath the bases of similar annual — shoots, by which I ain quite confident that all communica- tion through the alburnous tubes, with the stem, was wholly eut off: yet the sap passed into the annual shoots in the succeeding spring, all of which lived, and some grew with consitlerable vigour. I, at the same time, selected many latcrah branches, about three lines in diameter, in a nursery of apple trees, which I could easily secure to the stems of the adjoining trees to prevent their being broken. I then made an incision, more than two lines degp in each, on one side, and at the distance of six or seven Jines another inci- sion, equally deey, on the opposite side; and as I am quite certain, from the texture of these branches, that the albur- nous tubes passed straight through them, Iam equally cer- tain that every elburnous tube was at least once intersected, Yet the sap passed into these branches, and their buds un- folded in the succeeding spring, the incisions having been made in the winter. But I have repeated the same experi= - gent after the leaves have been full grown in the summer, and still the branches have continued to live. All naturalists have agreed in stating that trees perspire most in the summer, when their leaves have attained their . # Philo soph ieal Eransactions for 1801; Dp. od 302 On the Origin and Office of the Alburnum of Trees. full growth, and of course that much sap must ascerid at this period; yet at this period the tubes of the alburnum ap- pear dry, and to contain air only; which induced Grew to . suppose that the sap rose in the state of vapour; a supposi- tion by no means admissible. Yet it is, I conceive, evi- dent that the sap cannot rise, as a liquid, through dry tubes, nor in any state through intersected tubes; and therefore it , appears probabie that it does not rise at all through the tubes of the alburnum, and that those tubes are intended to exe-> cute a different office. : If the sap do not rise through the tubes of the alburnum, it must rise through the cellular substance ; yet the passage of any fluid through this has been denied by almost every naturalist, probably because coloured infusions have’ not 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, exudes from the bark, when de- tached from the alburnum, I 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- lular substance of an oak, it appears possible at least that the whole of the sap may ascend through it. Coloured tn- fusions do not, I think, in any degree, pass through the bark of trees, yet it is evident that the sap passes readily through it ; and therefore, should it be proved that such infusions do not penetrate the cellular substance of the al- burnum, the evidence which this circumstance would afford would be very defective. Amongst other experiments that I made to ascertain whe- ther the cellular substance of the alburnam 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 | effectually closed * Philosophical Transactions for 1807, p. 7. the On the Origin and Office of the Alburnum of Trees. 303 the alburnous tubes with a composition formed of calcined oyster shells and cheese *, and this was covered with a mix- ture of bees wax and turpentine, so as to effectually 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 in- sinuated itself between the alburnous tubes, in many in- stances apparently tnrough the cellular substance. This was most ebvious in the walnut tree, the young wood of which is very.white. The principal object I had in view in making this experiment, was to detect the passages through which I conceived the sap to pass from the bark into the aiburnuin f. From the preceding circumstances, I am disposed to infer that the sap secretes through the cellular substance of the alburnum ; and through this I conceive that it must ascend when the tubes were intersected in the preceding expcri- ments, and in those seasons of ithe year when the alburnous tubes are empty, though the sap must be rising -with great rapidity: and I shall endeavour to show that the presence 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 cap through those tubes. _ In the last spring, when the buds of the sycamore first ‘began to prepare for unfolding, I found that the sap abound- ed in the points at the annual branches; and at the sane time it flowed abundantly from incisions made into the al- burnum vear 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- * | have found this composition, and this only, to be capable of instan- taneously stopping the ‘effusion of sap. ftom the vine, or other tree, in the bleeding season. + Philesophical Transactions for 1807, p. 7. NUN 304 On the Origin and Office of the Allurnum of Trees. 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 bleedittg season. __ The sap must therefore have been, by some means, thrown. into the tubes above the incisions, for the quantity dis- charged from them exceeded more than a hundred times that which the tubes could have contained at the time the inci- — sions were made, even had every tube been filled to the ex- tremity of the most distant branch. And, as it has been shown that the sap can pass'up when all the alburnous tubes are intersected, 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 clude that the sap ascends, and it is not, I think, difficult to conceive that this substance may give the impulse with which the sap is known to ascend in the spring. I have shown _ that the bark more readily transmits the descending sap to- | wards the roots than towards the points of the branches *; and if the cellular substance of the alburnum expand and contract, and be so organized as to permit the sap to escape / more easily upwards from one cell to another, than in any ether direction, it will be-readily impelled to the extremities af the branches: and I have shown that the statement, so often repeated in the writings of naturalists, of a power in . ' the alburnum to transmit the sap with equal facility in op- posite directions, and as well through inverted cuttings as others, is totally erroneous ft. If the sap be raised in the manner J have suggested, much of it will 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 transpiration. And the cellular substance, being then filled, may discharge a part of its contents into nee 'burnous tubes, which again. ‘become reservoirs, and are filled to a greater or less height, Philosophical Transactions for 1864, p. 5. is Ibid. ’ ; in ‘ . On the Origin and Office of the Alburnum of Trees. 305 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! e 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. The albarnous tubes appear to answer another purpose in trees, and to be analog gous, in some degree, im their effects, to the cavities in the pene: of animals ; by which any de- gree of strength, that is necessary, is given with less expen- diture of materials, or the incumbrance 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 drom each other by the intervention of alburncus tubes, and consequently acting with greater mechanical advantage, than they would if placed immediately in contact wita each other. | _ I have shown in a former communication, that the spe- cific gravity of the sap increases during its ascent in the spring, and that saccharine matter is generated, which did not previously exist 1a the alburnum, nor 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 instrus nental in the ecneration of this saccharine matter. For | dis- covered in the lJast autumn, that much air is absorbed, or at Jeast ee during the process of grinding anus for the purpose of making cider, and that dng this abs orp- 02 tion of air, the juice of acid ee becomes very swect, fl acquires many de eyrees of Increased aneeae gravity ; and a_ similar absorption of air, with corresp: nding effects, is well known to take place in the process of malting. shall conclude with observing, that. in retracting the | opinion J formerly entertained respecting the ascent of the sap in the Aerio us tubes, Ido not mean to retract any opinion that I have given in former comniunications respect- ing the subsequent motion of the sap through the central . Weenie, the leaves, and bark ; or the subsequent junction of the descending with the ascending current jn the alburnum: Vol. 32. No. 127. Dec. 1808 “ U - every ote 4 306 On the Variegation of Plants. every experiment that I have made has, on the contrary, tended to confirm my former conclusions. I am, my dear sir, your much obliged obedient servant, Tuomas Anprew Knicur. XLV. On the Variegation of Plants. In a Letier to Ricaarp AnTHOny Satispury, Esg., F.R.S. and L.S., by THo- mas ANDREW Knicut, Esq., F.R.S. and L.S.* va MY DEAR SIR, # HOUGH variegated plants have long occupied the care and attention of the gardener, it does not appear that the pecu- liarities which distinguish them have much attracted the at- tention of the naturalist; and I am not acquainted with any experiments which have been made either to discover the cause of variegation, or the effects produced by it. Iam therefore induced to trouble you with an account of a few experiments which,I have made on one species of variegated plant, from which J obtained an unexpected and somewhat interesiing result. There is a kind of variegated vine, well known to garden- :- ers (the Aleppo), which affords variegated leaves and fruit 5 and as the grape, though small, possesses a very high fla- vour, and much richness, I wished to obtain some offspring either from its seeds or farina, with the hope of procuring berries of larger size, and at the same time of ascertaining whether its variegation would be transferred to the offspring. With this object in view T extracted the immature sta-’ mina of the blossoms of the white Chasselas, and white Fron- tignac vines; and at the proper subsequent period J intro- duced the farina of the Aleppo vine; from this experiment I 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 haa the pleasure to observe pur- ple stripes in the seed-leaves of several of them; and in the autumn the leaves of many were variegated. I did not how- ; / * From the Transactions of the Linnzan Society, vol. ix. On the Variegation of Plants. 307 ever obtain a single plant which promised to produce, or has subsequently afforded, either coloured fruit, or coloured leaves, free from variegation. When, on the contrary, I have introduced the farina of a black, or purple grape into the blossom of a white one, none of the plants I obtained have ever been 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 yarieties, in whatever soil cuttings taken from them were subsequently planted. But in the varie- gated vines the result has been wholly different; aud though the leaves and fruit first produced by some of them con- tained-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 variations, and the colours in them are in some instances confined to the upper, 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 tingting matter of variegated grapes, though probably not essentially different from that of others, is differently combined, and united to 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 inay be confidently in- ferred, that the nature of the union between the tingeing matter and the plants is very essentially different. All the variegated plants that I obtained from the farina of the Aleppo vine, are not only perfectly free from diseas¢ and debility of every kind, but many of them possess a more than ordinary degree of hardiness and vigour; and two of them appear much more capable of affording mature fruit, in- the climate of England, than’ any now cultivated. It is therefore sufficiently evident that the kind of variegation which I have described is neither the offspring of, nor con- : U2 nected \ ’ 308 On the Variegation of Plants. nected with, disease or debility of any kind. But the same in- ference must not be drawn respecting 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 dif- ferent shades of red and purple, like the leaves of the vines which I have described; but tn the cabbage these colours combine and melt into each othér, whereas in the vines the distinct colours are separated by well defined lines. The co- lours of the cabbage are transferred to its offspring, which ts perfectly hardy a vigorous. The spotted lettuce must also be classed with. varierated plants, and the offspring of this is as hardy as those of other varieties: but the most. common kind of variegation, in which the leaves are variously striped with white and yellow, though not the offspring, as some writers havé imagined of sha is, however, closely connected with some degree of debility ; possibly owing to the imperfect action of light, on all such parts of the leaves as are either white or yellow. For I have observed that variegated hoilies are less paticnt of shade than such as are wholly ereen; and I have never seen any plants, the leaves of which are wholly white or yellow that continued to live beyond a single season. A variegated plant of the raspberry, which sprang from seed in my garden, became wholly white in the third year; but it perisbed in the succeeding winter, and I should be disposed to conclude that plants whose leaves are entirely white or yellow, cannot long survive; but that Du Hamel* has described a variety of the peach tree, of which he says, ‘* son bois, ses feuilles, . ses fleurs, et son fruit, tant extérieurement qu’intérieure- ment, 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 conse- quence exists no more, Tam, &c., | TyHomas ANDREW Kee * tn his Treatise on Trees. —4rticle Peach ‘Tree. XLVI. Ex- [ 09] XLVI. Experiments relative to Coals and Cokes obtained _ from Wood and Pit-coal. By Davip MusueEt, Esq. ] NEED hardly ae that charcoal is composed of pure carbén, or diamond, combined with a certain portion of . oxygen—and is therefore considered as an oxide. Oxides of carbon are furnished in greater or less portions, and of va- rious degrees of purity, by every substance in the vegetable kingdom. Almost every substance in the animal ceconomy yields it, and frequently in a state of comparative purity. In ihe mineral kingdom, in pit-coal, plumbago, mineral pitch, naphtha, &c , we find it bearing a greater proportion to the other ingredients of the compound than either in the ani- mal or vesetable departments. The proportion of oxygen “united with carbon to form charcoals has not hitherto been ascertained; put from the great dose necessary to form carbonic acid, it is probable that some oxides contain from 30 to 50 per cent. This will be made to appear hichly probable, from the combustion or distillation of different substances in close vessels. No direct experiment has been hitherto made to ascertain the precise quantity of oxygen united to the coaly residue obtained in the preparation of coke, charcoal, or any species of coal; but by a comparison of their carho- nating effects, when applied as agents in the dry way of ex- periment, or even upon the more enlarged scale of manu- facture, we may form a pretty correct estimate of their real value, or their approximation to the state of diamond. From numerous experiments which I have made, it ap- pears to me highly probable, that the oxide of diamond exists ready formed in almost every substance that yields a car- -bonaceous residuum. It has been conceived by some, that the oxide is formed in consequence of the ignition of the substance from which charcoal is meant to be obtained, by the combination of the oxygen liberated from the shnieeone ric air, or from surrounding bodies; and that, according to the quantity of oxygen combined with the matter of carbon, the ceasing oxide would be more or less debased. It is U3 * probable ~ x { 3:0 . Experiments relative ta-Coals and Cokes probable that this takes place to a certain extent, and that all carbonaceous matter prepared in contact with atmosphe- Tic air is inferior in point of purity, or, in other words, 1s not so highly de-oxygenated as that prepared in close vessels. Ido not find, however, that, by having recourse to close vessels where there is no contact of atmospheric air, the re-. sulting product is materially altered as to colour and general appearance, or that the oxide of diamond. apparently exists in astate of diminution. Its carbonating effects, however, become wonderiully changed by such a Pa of procedure ; and subsequent experiment, ja various stages, develops many | characteristics not unworthy of an pase to the state of diamond. ; This change of quality may arise from another source than simple distillation im close vessels, and the prevention of the contact of external air. If the heat of the distillation is urged beyond a dull red colour, or eyen.continued longer at the usual temperature, . the oxide begins to de-oxidate itself, and the product will be found materially changed as to its usual affinities. It will be found more difficult to ignite in. common open air. Its com- bustion unless impelled with mechanical violence will move on sluggishly, and under every circumstanee.a higher tem- perature and longer contact will be requisite, to effect an union with its usual relations. The extent of carbonaceous principle arising from a given weight will, however,«be in- creased in the same. proportion as the substance has been de-oxidated, A greater quantity of carbonic acid gas will be obtained from the same weight of oxide, and of course a greater quantity of carbon set free. It is difficult to say to what extent.this de- of dee prin- ciple might be carried. In heats of 160 and 170°, of Wedg- wood,. the increased density of the carbon, particularly if im the state of powder, and the uncommon depth of lustre which the black assumes, are evidences that some material change has passed upon the arrangement of its constituent parts... There,can, however, be no doubt that there exist certain fixed limits, unless a third affinity be interposed, be~ yond which \earbonaceous matter ceases to de-oxidate it. 3 : self; : obiained from Wood and Pit- coal. 311 self: or shouldits operation continue in temperatures when we cease to perceive any material change, its progress Tnost probably would be so slow as to require ages before the second portion of oxygen was set free. This last will be regu- lated by the nature of the affinities betwixt carbon and oxy- gen, and the progress of their action upon cach other during the exposure. If the affinity of de-oxidation is aired once to he established, and the carbonaceous matter to be approaching to the state of diamond, by sacrificing part_of itself in com- bination with the oxygen, its tendency to do so will be di- minishing in the ratio of its continuance, unless some new action, by increase of temperature, affinity or otherwise, be excited. The ultimate period.of de-oxidation will therefore most likely be retarded by both a want of time and means. The difficulty arising from the. former, and want of tem- perature to extract or give both an additional affinity that would clear the oxide of its second and third portions of oxygen, are evidently so great as to leave little hope of form- ing any thing in this way purer than a highly incombustible coal, : ee The combustion of wood or of pit-coal to form coke or charcoal may be considered as a principal step towards de- oxidation. In the natural state of wood and pit-coal, the carbonaceous matter appears to be highly surcharged with oxygen, which is in part carried off in burning. If the ignition has been performed in open fires exposed to external air, a greater portion of the original oxygen will remain fixed. On the contrary, when distillation is per- formed so as to secure the product from the contact of at- mospheric air, the portion of carbonaceous matter, which in all cases is unavoidably lost, is here combined with the oxy- gen of the oxide, which 1s left in a state of comparative purity, in place of being carried off in simple combustion by the external air. Every oxide of carbon that has bitherto been examined contains a portion of foreign matter in the state of earths or salts, and it appears by experiment that even the diamond is not eutirely free from such an alloy. ‘ U4 100 parts $12 Experiments relative to Coals and Cokes 160 parts of oxide of the following substances from the vegetable kingdom have been fu und thus alloyed: Oxides. Ashes, Oxides. ‘Ashes. Walaut, - - -8°952 | Norway Pine, - 1°88] Elm, - - 3°300 Chesnut, - - 1:860 Holly, 2 - 5:348 | Laburnum, + .. =. 4°800 Scotch Pine, - 2:900 |-Oak, . - - 1°865 Beech, ° = ~ 4-800 | Ash, - - 4:973 American Maple, - 3:860 | Birch, - - 19°309 — Mahogany, : - 3-846 | Sycamore, - 5406 Sallow, - - 69135 Lime, = = 3°679 AbnediGun Black Beech, 4°831 Pit-coal affords, after burning or distillation, a large por- tion of coke or oxide of carbon. This, in like manner with that procured from wood, contains various proportions of alloy. ; me The coals found in the extensive coal country around Glasgow are divided into five workable measures, No. 1, 2, 3,4, 4. ‘These are possessed of various local names, and. their-analyses in different places give different results. Even the same measure always contains two and not unfrequently four different qualities, possessed of parts dissimilarly com= pounded, and yielding diferent products when used as agents n experiments. Under such circumstances, a classification of these various qualities will serve better than an enumeration of every particular measure,to convey an idea how these oxides are compounded. The Scotch coals in general, in that quarter, may be short- ly arranged ander soft, mixed, and hard coals. "The soft may again be divided into free coal, i... coal that burns inihe fire without welding. or caking; and into coal that in burning adheres more or less together, or that enters into a bituminous kind of fusion and forms a firm compact cinder. ; Each of these varieties again vields a quantity of ashes, which in colour may proceed from pure white to deep brown- ish red. This distinction is of the utmost importance, -and ought to be the subject of another division. So that in order to form a correct idea of the nature of the resulting oxide Re oa ee obtained from Wood and Pit-coal. ~313 oxide from each of these varieties, the following arrange- ment will be necessary : ‘Ist, soft coal free, white ashi, od, oe , red ash. 3d, ——— caking, white ash. 4ih, —-~ —— -——,, red ash. The following are the results of five specimens analysed from the ist measure of the Great Coal Field around Glas- gow, distinguished by the following coal names; com- missary coal, upper coal, double pat, &c., corresponding to No.-7.— 160 parts of oxide of — Ist specimen contained of ashes 3:14 ied 4:05 3d : 2°98 Aled a he BOs pe ee 2°80 Tht four follow ng varieties are extracted fri a number of results, of which they may serve as an average 5 many of ee taken from the same measure, and even in con- tact with the former. These correspond with variety No. 2 2, 100 parts of oxide of — ist specimen contained of Aces 37°15 ad a 36°10 Sc. 30°70 Ath 25°50 The following results are. taken from experiments with welding coals, No. 3. In general these ceals leave a red or brownish-red ash. Those found in Yorkshire, and used at the furnaces for iron-making, contain the whitest ash. 100 parts of oxide of— i 1st specimen contained of ashes 2°55 2d oe 6°44 3d ——ase 5°82 4th -———— 8°15 5th -__ 4°75 6th —_—— 3°85 No. 4, or that variety of soft coal that welds and leaves an ash of a red colour, or of any intermediate shade betwixt alight ochrey hrown and adeep red brown, contains a greater variety of alloy than any other description of coal. The coals got at the Newcastle and Sunderland collieries are chiefly A ‘ 314 Experiments relative to Couts and Cokes. chiefly of this description, and yield ashes of almost every shade from hght brown to deep brown red. The following results will show the immense variety of alloy that is erates i oxides taken from this class. (No. 1 contained of light brown ash, -: | - 2°85 | 2 0 — do. earthy, - 4:7 et 3 do. ‘deeper, - 5 ae oe 40 ———-= brown, - - 6:5 5 5 dark do. - - 6°90 | 6 —-—~ deep vivid brown, - §&'50 Lap. (oo Sees dull earthy do. - 10°75 = 8 do. densest) = - 13°38 5 | 9 brownish red, - - 14°95 ‘= 10 do. deeper, ait - 17°40 : i o—— dull reddish brown, - 25°80 12 ———— do, stony, - - 34°66 { 13 —— sulphuret of coal and bitumen, 48°50 The 2d, or mixed class of coals, being in general Jess dis- similar to each other, afford a less variety of alloy. The ashes of this kind of coal are in common specifically lighter than those of any other class, and vary from a blueish RR to a primrose colour. The purity of the oxides obtained from it may be gathered _ from the following results : 300 Be of aioe Ist specimen yielded 1°25 of ashes, 2d —_——. 9°55 3d ——__—. 4°75 r 4th —_——___—. 4°90 5th ——— 5:80 6th —— 7°50 7th —— 1°87 8th os 2°30" The 3d, or hard ¢ coals, judging from appearance and from the analysis of their oxides, may be divided into three ya- rieties ; candle or cannel coal, hard, and stony hard. 100 parts of the oxides of candle coal yielded of alloy ag follows: Ist specimen, from Wigan, - a peta 2d Lesmihago, - 9°88/ Ashes ofa sd —— _ Leven, - - 15°75 > pure white 4th —— Glascow Field, - 29° 204 colour. 5th — do. - om 4PI5S Coke, Remarks on Falco cyaneus, &e. 315 Coke, or oxide of carbon, obtained from hard goal, is ge- nerally combined with.a pure white ash, and frequently pos- sessed of considerable density. The quantity of this alloy may be estimated from the following results from 100 parts of each: Ist specimen of Bee contained of ashes 6:78 ad 8°25 3d —- —_—— PSS 7°50 4th —_— —_——- SSS 0°54 5th —- — —_ 11°78 6th aS 12°12 That particular variety of coal, which has been described as belonging to the hard coal class, under the name of siony hard, after combustion leaves a white stone covered with very fine white ashes of the same colour. In many cases the proportion that the allov bears to the carbonaceous maiter is equal, and sometimes greater.—One hundred parts. of cokes— Ist specimen conta ained of ashes 15°75 ed 19°50 3 seen 28:07 4th —~ po 39°54 5th — 47°30 6th ————- 51°90 Besides these experiments relative to coals and cokes pro- duced from wood and pit-coal, I have performed a nutmber of others upon various substances, animal and vegetable, with a view to produce oxide of carbon, to form a general estimate of their comparative merits. Some of these I shall ‘send you for a future number of the Philosophical Magazine. XLVII. Some interesting Additions to the Natural His- tory of Falco cyaneus and pygargus, together with Rez “marks on some other British Birds. By Gnorge Mone TAGU, Esq. F.L.S&,* FaLCO CYANEUS. Ind. Orn. i. p. 39..94. Hen Harrier, Lath, Syn, Tuart the natural history of a bird indigenous to this coun- try, and by no means uncommon, agit have so long cone * From the Transactiens of the Linnzan Society, vol. ix, . ° @ tl nued 316 | Remarks on Falco cyaneus and pygargus, tinued in obscurity, must, to those not in the habit of inves- ligating nature, appear very extraordinary ; but. the seruti- nizibg ornithologist will recollect how few opportunities oc- eur of proying, or-controverting, a generally received opt- nion by ocular demonstration. Upon the present subject the mind of the scientific world has been so extremely. oscillatory for want of proof, that most authors have re- dated the opinions of others, or reasoned from concurring circumstances blended with parole evidence. In fact, it must be confessed, that although [ had many reasons for believing the Hen Harrier, Falco” cyaneus, and Ringtail, Falco pygargus, to be the same species, yet I could not ad- duce any well-authenticated proof that this was really the fact; when the Ornithological Dictionary was published. It is true that I was assured by a mést worthy and scientific clergyman in Sussex, that the gamekeeper of general Pres- cott, in whose neighbourhood he resided, had actually shot both these birds from the same nest, and that they had both been preserved in one case, and were in the general’s pos- session. That my friend gave implicit credit to the keeper’s _ assertion I could not have the least doubt; but as I had been assured from another quarter, that not only the male and female Hen Harrier had been shot, which belonged to the same nest, but that the young which could just fly were also killed, and were of the same cinereous-gray colour as, the parent birds ; Who, perplexed with such opposite as- sertions, could determine? But, to close this discordancy, — J shall transcribe a passage from the latest publication on ornithology exclusively, that has appeared in this country, except the Second Supplement to the General Synopsis. The author’s words are these: ‘ It has been supposed that this and the following (relating to the two birds in question) are - male and female; but the repeated instances of Hen Harriers of both sexes having been seen, leave 4 beyond all doubt, that (hey constitute two distinct species. Such a strong unqualified assertion appearing on public record, stamped with tbe authority of the author without reference to the nature of the proof, should seem to pro- sced from personal knowledge : and as the only positive proof ta and some other British Birds. 317 to be obtained in such case is by dissection, it might naturally be presumed that the author had really determined this long desideratum by the knife. That male Ringtails have frequently occurred has been well and repeatedly authenticated, but no well attested fact of a female Hen Harrier is, T believe, to be found. Those’ who have formed their own opinions upon this subject will not readily adopt that of another, without direct and incon- trovertible proof ;-and since there are two opposite opinions founded equally upon painise assertions, it will not be al- lowed by one party that both the F. cyancus and F. pygargus having been shot at the same nest, 1s a direct proof -of their being the same species. Nor, on the contrary, will the othce be Convinced of the fact by a bare assertion that female Hen Harriers have been observed ; for it may be said, that as birds of prey plunder the nests of others, one of these birds might be shot in that act of depredation. And the cifcumstance of a single instance of a female bird appear- ing in the habit of a Heit Harrier, may be disputed as equal- ly liable to objection, since instances have not been wanting to prove that female birds have occasionally assumed the male plumage. Such difficulties could only be removed, and the fact indisputably established, by finding the nest, and rearing the young; and IT am happy in being now enabled to lay before the Society the result of an experi- ment of this nature, which must bring all controversy to aconclusion. To a member of this Society, the Rev. Mr. Vaughan, we are greatly indebted, as the discovery might yet have been protracted to a series of years, but for his kind communication and essential aid towards the development.of the subject. About the latter end of June, in the year 1805, my friend informed me that his servant hed found the nest of a Hen Harrier in some furze, which contained three young, and au addle egg ; at this time the infant birds were very small, and ‘only covered with white down: it was therefore determined ‘ to take them as soon as we deemed them sufficiently large to be brought up by hand: when that period arrived, the servant was directed to shoot one, and if possible both of the old birds 318 Remarks on Falco eyaneus and pygargus, birds, previously to his bearing eo what was considered a prize of no small value. / On the return of the man with the young, he brought with. him also the Hen Harrier, which he assured us he had, under concealment in the furze, shot in the act of dropping a thrush | into the nest, while the female (as he seemed to consider the other, and which he described to be a brown hawk) was co- vering the young. He afterwards. shot at and wounded the female, but could not obtain it. Strong as this person’s evidence was in our own minds, yet it conveyed no more to the public mind than what had been so repeatedly asserted on similar authority: being, however, in possession of the a€rie, the means were in our power of fully determining the point in question ; and to enable me to observe and note the changes that might take place in the plumage, I undertook fe care of the whole brood. At this ume the two largest had thrown out many ry hea sufficient to discover the pluniasd of the Ringtail approach- ing; the other, by its appearance, must have been hatched much later. In about a month it was evident from size, that there was but one male, so that all my hopes rested upon this single life. As they became full feathered, there was at first no distinction in plumage, but the eyes of the supposed male were always lighter than in the others, whose irides — were so dark as not to be distinguished at a small distance from the pupil. In the dress of the Ringtail the whole con- tinued through the winter, when the one which had been weakly from the first, died : this circumstance induced me to force apremature change in some of the quill and tail feathers of the others, ae some accident might frustrate my earnest desire of bringing matters to a arcane proof ; and about the middle of Ju:.: I was highly gratified by dis- covering an appearance of the new feathers in the place of those which had been plucked out, and that clearly evinced the smallest bird to be a Hen Soop tne and the larger to be a Ringtail. "i Thus I had compelled nature to declare her secrets before the: appointed time ; for in every other respeet their pluinage. ' was. and some other British Birds. 319 was yet similar, excepting about the sides of the face, which were paler in colour in the former, in which also the irides were of a dull _ yellow, somewhat mottled, whereas in the lat- ter they still continued dark. The shyness of these hawks had occasioned their breaking . most of their larger feathers, although confined in a place ten feet in length by five in width; and as their regular moulting season was advancing, they were turned into a garden sur- rounded by a wall, where, after some time, the female died of the cramp in her legs. The male had about.the 20th of July thrown cut many of the new feathers naturally, especially the greater coverts cf the wings, and a few gray feathers in different parts of the body. On the 20th of August, the greater part of the quill and tail feathers were grown to their full length, anda eras dual increase of gray feathers appeared on most other parts : the eyes also became more orange, but it was not til the middle of October that it had attained that state which made it desirable to retain, as an existing fact of the changes it was then killed, and is nowin mv museum. Jn this state the plumage of the Rinetail or female still remains about the neck, the smaller coverts of the wings, the thighs, and part of the belly, intermixed with the male plumage ; the top of the head and wreath have also a mixture of the feathers of both sexes: the quills, scapulars, and tail, are complete- ly masculine; in the last of these there are a few smal! broken bars of cincreous brown ona white ground, in the three outer feathers, the exterior margins cinereous-gray ; the six middle feathers are almost wholly gray, and the markings are very obscure beneath. Having~y the most _powerful evidence traced this bird from the egg to that state approaching maturity, which so» elearly and satisfactorily proves that ce cyuneus and py- - gargus are actually of the same specics, two queries arise out of the observations of different ee ts... [t. has been. res. marked by Doctor Lathan, that no author has mentioned the Hen Harrier as a bird of the American continent. Do the females only:migrate to those particular parts where they have been observed, -atter the breeding season ; or is not the. ‘ 4 transe 320 . Remarks on Falco cyaneus and pr yg ray BUS 5 transatlantic Ringtail a distinct species, not differing irt sexual plumage ? The other query is with respect to the sexual distinction of the ash-coloured® Falcon of the Orn. Dict. which has been considered to be most probably the Northern Falcon, or Falco hyemalis ; for although the male of this species has only occurred to me, yet, nothing’ having been related by any author to induce a belief that the sexes are essentially different in plumage, may we not reasonably conjecture that the female F. hyemalis has been mistaken fora F. cyaneus, and possibly occasiened some of the ac- counts related, ‘concerning the similitude in the plumage of both sexes of the latter? Indeed the F. kyemalis has ge- nerally been described to be considerably jarger than those males which have ceme under my inspection,—a circum- Stance serving to strengthen the opinion that’ the sexes are similar in plumage, (the females of this tribe being always ' the largest,) and may have been confounded with the cya- neus, as was the case of the two specimens which were sent to me. From the account here given of the Hen Harrier, it is poe clear that the change of plumage is effected in the autumn after it leaves the nest ; and as it is between three and four months in the act of moulting, it is certainly very extraor- dinary that so few instances have occurred of its being killed in that state which might have been decisive. That such has heen taken 1s evident by the description of Falco Hudso- nius of authors, which is doubtless this bird in change of plumage ; and it will be observed, that mention is made in the Ornithological Dictionary of some slight indication of such a change ; one had only a few gray feathers, beginning the change, aud another had several brown feathers in the smaller coyerts of the wings, which now appear to be the last that are changed. | I have now only to remark that shiek nest of this bird was composed of sticks rudely put together, was neatly flat, and placed on some fallen branches of furze that supperted it just above the ground. The addle egg found in the nest is little inferior to that of the Moor-Buzzard, and similar in shape and colour, being spotless, but cf a sullied white. FaLco and some other British Birds: - 321 FALCO CINERAREUS. Ash-coloured Falcon. Orn. Dictionary. By the examination of a recent specimen of this bird killed on the 10th August 1803, near Kingsbridge in Devonshire, I am enabled to add somewhat to the description of it, and to correct a mistake in the work above referred to, which I’ trust wiil not be unacceptable to the ornithologist. It weighed nine ounces and three quarters: length, eighteen inches; breadth three fect eight inches and a half ; length from the elbow to the end of the third quill feather, which is the Jongest, fifteen inches and half; length of the tail from the gland on the ritmp nine inches and a half. Bill black, the base and cere greenish: irides and eyelids bright yellow: crown of the head, cheeks, throat, under part of the neck, and upper breast dark asn-colour: upper part of the neck, back, and scapulars cinereous-brown; the latter is cinereous at the base of the feathers with the tips brown : the smaller coyerts are marked in the same manner as the ~ scapulars ; the greater coverts are cinerecous-brown, the ex- posed part of each feather darkest, but not tipped like the others: the eight prime quills are dusky-black, the last with a dash of cinereous; the first 1s very short, the third by far the longest: secondary quills cinereous brown above, pale beneath, with three remarkable dusky-black bars across them, nearly in parallel lines, each balf an inch in breadth ; - one only of which is to be seen on ihe upper side of the wing, the others being hid by the coverts, this is about two inches from the tips of the feathers ; on the under part of the wing two of these bars are very conspicuous, the other close to the base is much paler, and hidden by the under coverts, the first row of which is white, with a large dusky bar across their middle; the rest are bright bay, more or Jess spotted, barred, or margined with white: the under parts of the body, including the under tail coverts and thighs, white, with a broad streak of bright bay down the shaft of each feather: under scapulars with broad alternate bars of bay and white : the tai! is somewhat cuneiform, the two middle feathers dark brown, or dusky, the rest dark ‘ash-colour, Vol. 32. No. 127. Dec, 1808. >. oe palest 322 Remarks on Falco cyaneus and pygargus, palest on the two or three outer feathers, which have also their inner webs approaching to white; all except the two middle have four equidistant bars on the inner web, taking - in the shaft ; these on the two outer feathers are bay, the rest more or Jess dusky, with a ferruginous tinge on those at the base: legs orange yellow, rather long and slender: claws small black. : In, the original description of tis species *, taken from a cased specimen, the greater coverts are, by mistake, said to have dusky-black on the outer webs towards their middle, forming a small bar; whereas it will be now observed, this visible bar on the wing above is on the secondary quills, and not on the coverts. - The bird from which the above description is taken is a male: it has the feathers behind_the ears short, but no ruff. continued round the head, as in the Hen Harrier. .It was in good condition, and had in its stomach a sky-lark, and yet its weight was not so much as that of the Hen Harrier by three or four ounces ; though its length and breadth are much superior, by reason of its long wings and tail. It mast also be remarked that it appears to be at least a year old bird, as some of the quills are moulting ; the first and second feather of the secendary quills in each wing are not full grown, but: are of the same colour as the rest, and possess the same three bars. I am not enabled to offer any thing further on the synony- ma than what has been given in another place; it differs a little, it istrue, from the Falco hyemalis +; but when it is considered how little that species seems to be known, some allowance must be made for want of a more minute descrip- tion : there seem, however, some marks of such near affinity, that I trust it will hereafter be found the same. Whether this is migratory with us is not at present to be fully deters . mined; the time of the year in which this was shot is rather too early to induce a belief that it is a winter migrant; and the only one besides that which has come under my inspeéc- tion I think was killed in November, which indicates a win- * Ornithological Dictionary. — . + Latham’s Synopsis. — ter , « < —— and some other British Birds. 323 ter residence with us. It is, however, more probable that this species. may be indigenous to us, and that it has fre= | quently been mistaken for-a variety of the Hen Harrier. Sytvia DARTFORDIENSIS. Ind. Orn. ii. p. 517. 31. Dartford Warbler. Lath. Syz. In a paper which Thad the honour to lay some time since before the Linnean Society, some notice was taken of the discovery of this little bird in the southern parts of Devon- shire: and I there remarked that, as it had been so frequently observed to be a winter inhabitant, a circumstance not fa-. vourable to its being a migrative species, (as it was said to breed in Provence, on the continent so much further south,*) I was not without hopes of ultimately proving it indigenous to this part of England. . _ My opinion that this species of Warbler bred with us, was greatly strengthened by a letter which I had the pleasure of receiving from a scientific friend in Cornwall, well known in the literary world ¢, who assured me that his brother had observed these birds for several years to inhabit furze, near Truro ; that last year, as well as the present, they were plen= tiful during the summer season; and that he had not only seen them every month in the year, but had observed young ones soon after they had left the nest, though his search for the nest and eggs had been in vain. This information redoubled, if possible, my ardour, and I visited a large furze common in my neighbourhood, where I had seen several the preceding autumn; and upon close search on the sixteenth of July, three pair of old birds were observed, two of which had young evidently by their extreme clamour, and by frequently appearing with food in their bills. The boldness and excessive garrulity of one pair in- * Provence is situated between 33 and 34 degrees north latitude, and 5° and 7 east longitude; and therefore, as these birds have been also found in England in latitude 5\,and west longitude 5, there can be no doubt but all the intermediate space, taking in nearly the whole of France, is inhabited bythem more or less, whenever the situation is congenial to their habits, + Mr. Stackhouse, of Pendarvis. % XK 2 duced 324. Remarks on Falco cyaneus and pygargus, - duced me to believe that the nest was near at hand; but it was not without two hours strict attention to the actions of — the parent birds, that I discovered a single young one on the ground ; this appeared to be too small to voluntarily leave the nest, which was probably within a few feet, but which, from the almost impenetrable thickness of the surrounding furze, I was not successful in discovering. Oh the 17th my researches were renewed, and after three hours watching the motions of another pair, I discovered the nest with three young; it was placed amongst the dead branches of the thickest furze, about two. feet from the ground, slightly fastened between the upright or main stems, not in a fork. Ou the same day, close to where I found the single young bird, two were observed to be busied, carrying materials for building ; and by concealing myself in the bushes, I soon discovered the place of nidification, by the continued returns of the birds with something in their bills, for making their nest; and, upon examination, I found it was just begun. Extraordinary as it may appear, there is great reason to be- lieve that this was the same pair from which I.had the day before taken the single young one. Is it not possible that the inclination of the parent birds to propagate again, was the cause of the young leaving the nest prematurely, in de- fect of a sufficient supply of food, and that the other young perished? A circumstance so singular can no more be de- nied than positively asserted; but as I could never observe more than one pair near the place, there is reason to believe, though extraordinary, that it was really the case, and that they actually began a new nest the day after they were de- prived of the only surviving young. The nest appeared to be finished on the 19th, but it pos- sessed only one egg on the 21st in the afternoon, and on the 26th it contained four, when the nest and egges were’ secured. tad i ores vag This nest was placed near the top of the furze, in the thickest part, about four feet from the ground, but so well concealed that, although the birds were repeatedly seen to. fly in with building materials in their bills, it was with the . > greatest. ~ and some other British Birds. 325 greatest difficulty found. The continued flirting of these birds from bush to bush, and through them, is so extremely. deceitful, that it is scarcely possibie to notice the spot, amongst such an uniformity of cover, where they deliver the contents of their bill, especially as ee frequently retire from a very different part. Like the other, this: nest is composed of dry vegetable stalks, particularly goose grass; mixed with the tender dead branches of furze, not sufficiently hardened to become pricks ly; these are put together in a very loose manner, and in- termixed very sparingly with wool. In one of the nests was a single partridge’s feather. The lining is as sparing, for it consists only of a few dry stalks of a fine species of carex, without a single leaf of the plant, and only two or three of the panicles. This thin flimsy structure which the eye pervades in all parts, much resembles that of the whitethroat. The eggs are also somewhat similar to those of Sylvia cinerea, but rather less, weighing only 22 grains; like the eggs of that species, they possess a slight tinge of green ; they are fully speckled all over with olivaceous-brown and cinereous, ona greenish- white ground, the markings becoming more ae: ene a zone at the ‘patie end. Whether the Dartford Warbler usually breeds so ma is not at present to be determined ; but as I found two. pairs with young at the same time, a have great reason to be- heve another pair was sitting about the same period, it is reasonable to conclude that.they do not: propagate very early,—or how are we to account for the loss of the first nests of all these, for there were no young birds to be found flying amongst the furze? I shall now return to the young birds, which I considered ‘as no_small treasure: the first, which was found on the ground, had been three days in my _ possession before the others were fit to take*, and then being able to fly a Nhittle, * There isan exact period of age which is the best for rearing young birds by hand, this is when the tips of the quillsand the greater coverts of the svings expose a portion of their fibrous ends, X18 ~~ was $26 Remarks on Falco cyaneus and pygargus, was put into a nest of chaffinches, and placed ina box; and so much did he like the warmth, that he rested perfectly contented, and though he would for several days after fly up to the top of the box to be fed, yet he retired as soon as saz. tisfied with food, and cuddled amongst his companions. By experience, grasshoppers, which at this season of the year are to be procured in abundance, are found to be an excellent food for all insectivorous birds : ‘these, therefore, at first were their constant food, and after five or six days a mixture of bread, milk, chopped boiled meat, and a little finely pounded hemp- and rape-seed, made into a thick paste, was sometimes given, to wean them from insect food by degrees; this they became more partial to than even grass- hoppers, but they afterwards preferred bread and milk with pounded hemp-seed only, to every other food, the smaller house or window flies excepted. Before these birds left the nest I put them into a pair of scales, and found the four weighed nine drams, which on an average is two drams and a quarter each. At this time they collectively ate in one day upwards. of five drams of grasshoppers, which is one dram and a quarter each, so that in two days each consumed more than its own weight. Such a repletion is almost incredible, and doubtless greatly be- yond what the parent birds could usually supply them with, which by observation appeared to consist of variety, and not unfrequently small phalenz: their growth, however, was in proportion to this large supply of food. \ This interesting little family began to throw out some of their mature feathers on each side of the breast about the middle of August, and the sexes became apparent. At this time they had forsaken their grasshopper food, feeding by choice on the soft victuals before mentioned. The nestling attachment is very conspicuous in these little birds towafds the dusk of the evening, for a long time after they have forsaken the nest ; they become restless, and ap- parently are in search ofa roosting place, flying about the cage for half an hour, or until it is too dark to move with safety, when a-singular soft note is uttered by one’which has chosen a conyenient spot for the night, at which instant they and some other British Birds. 327 they all assemble, repeating the same plaintive cry. In this interesting scene, as warmth is the object of all, a consider- able bustle is observed, in order to obtain an ‘inward birth, those on the outside perching upon the others, and forcing in between them: during this confusion, which sometimes - continues for a few minutes, the cuddling note is continually emitted, and in an instant all is quiet. Nothing can exceed the activity of these little creatures 5 they are in perpetual motion the whole day, throwing them- selves into various attitudes and gesticulations, erecting the crest and tail at intervals, accompanied by a double or triple cry, which seems to express the words cha, cha, cha. They frequently take their food suspended by the wires, with their head downwards, and not unusually turn over backwards on the perch. The males, of which there were three out of the four, began to sing with the appearance of their first mature | feathers, and continued in song all the month of October, frequently with scarce any intermission for several hours to- gether: the notes are entirely native, consisting of consi- derable variety, delivered in a hurried manner, but in a much Jower tone than I have heard the old birds in their natural haunts. This song is different from any thing of the kind I ever heard, but in part resembles most that of the stone-chat. The Dartford Warbler, like the whitethroat, will some- times suspend itself on wing over the furze, singing the whole time: but is more frequently observed'on an upper- most spray, in vocal strain for half an hour together. Buffon, who appears to have been the first and perhaps the. only perscn on the continent who knew any thing of the Dartford Warbler as a naturalist, seems to have known very litthe more than the bird itself, and that it had been found in Provence, (as his name evinces,) but nothing of its habits, If he had not figured it in Pl, enl. 655. f. 1, it would scarcely be conceived that the history given by that author could be intended for this species. We must therefore con- clude that he, hxe other great men, was deceived in that part of its natural history related by M. Guys of Marseilles, from whom he seems to have collected, that this bird not only feeds amongst cabbages on the smaller lepidopterous Xx 4 insects, 328 Remarks on Falco cyéneus and pygargus. insects, but that it roosts amongst their leaves, to secure itself against the bat, its enemy. To this curious account, implicit faith cannat be given ; for as on the continent furze is by no means uncommen, except in the more northern part, there can be no reason to believe the nature of this little creature to be so different in Provence from what it is ia England, where it is only found to mhabit the more extended tracts covered with that shrub. If indeed it were necessary to hide itself at night from the bat, furze is better calculated for that purpase than cabbages ; but I believe there is no species of that genus in Europe sufficiently large to attack even our most diminutive bird, the gaiden-crested wren, which we may safely conclude bas no occasion to hide itself from any European species of Ves . pertilio. Science, unfortunately, is too frequently blended with fiction, occasioned by too large a share of credulity ; the detection of such errors is a work of time, and a series of» years are. often required to correct what, according to the general merit of an author, has more or less been stamped with credit. Experience from ocular demonstration has at last been able to collect materials concerning the natural history of Syluza Provincialis, which serves to evince that M. de Buffon was “misled, and that, in fact, little was known of the habits of this elegant little warbler till the present discoveries. BIRDS NEWLY DISCOVERED IN GREAT BRITAIN. In this place I shall take the opportunity of recording some birds which, as far as I have been able to discover, have not iill recently been found in this kingdom, eee now claim a place in the British Fauna. ” ARDEA ZZQUINOCTIALIS. Ind. Orn. ii. p. 696.70. Little White Heron.. Latham. Syn. v. 0. 93. ‘No. 63.: This bird was killed in Devonshire the latter end of Oc« tober, in the year 1805, and is now in my. museum. _ dissection it proved a female. TANTALUs Memoirs of Erasmus Darwin, M.D.- 329 TANTALUS VIRIDIS. Ind; Orn. its pPago7s. ASs Green Ibis. Lath. Syn. vy. p..114. 13. This species was shot in the interior part of Devonshire about the middle of September, in the same year as the pre- eding: itis a male, and occupies a place with the last. Whether this, the bay, and the glossy ibis are specifically distinct, admits of doubt, and requires further investigation, SCOLOPAX NOVEBORACENSIS, Ind. Orn. iw. p. 723. 32. Red-breasted Snipe. Lath. Sym. v. p. 153. 26.. A small flock of these extremely rare birds made their ap- pearance on the coast of Devon in the spring of the year 1803, one of which was shot in my neighbourhood, and is © now in my museum. Soon after, I received information that a similar bird had been shot at Weymouth, in cem- ‘pany with several others ; and the skin of another was sent to me, which had been killed at Sandwich in Kent, pro- bably belonging to the same flock, as the account of the number seen last on the east coast tallied nearly with what first was noticed in ‘the west, allowing for those which are stated to have been shot. iis GLAREOLA AUSTRIACA. | Mid Orn: We Po7sso v. Austrian Pratincole. Lath. Syn. v. p. 222. £.85. A bird of this species has been shot, at or near Liverpool in Lancashire, and is now in the museum of Lord Stanley. Having been informed that a publication will soon make its appearance wherein not only the particulars relative to the capture of this bird will appear, but also a very excellent figure, I shall forbear to anticipate the author’s intention. XLVI. Memoirs of the late Erasmus Darwin, M.D. [Continued from p. 166.] “DARWINIANA. : Hreparis tumor.—The liver becomes enlarged from defect of the absorption: of mucus from its cells, as in anasarca, especially 330 Memoirs of Erasmus Darwin, M.D. especially in feeble children ; at the same time less bile is secreted from the torpid circulation in the vena porta. And as the absorbents, which resume the thinner parts of the - bile from the gall-bladder and hepatic dacts, are also torpid or quiescent, ihabiled is more dilute, as well as in Jess quan-' tity. From the obstraction of the passage of. the blood ihrough the compressed vena porta these patients have tumid panes; and pale bloated countenances ; their paleness is probably owing to the deficiency of the quantity of red glo- bules in the blood in consequence of the inert state of the bile. These symptoms in children are generally attended with worms, the dilute bile and the weak digestion not destroying them. In sleep I have seen fleuke-worms tn the gall-ducts themselves among the dilute bile; which gall- ae they eat through, and then produce ulcers, and the hectic fever, called the rot. M. M, After a calomel purge, crude iron-filings are spe- cific in this disease in children, and the worms are destroyed by the returning acrimony and quantity of the bile. A blister on the region of the liver. Sorbentia, as worm-seed, san- tonicum. Columbo. Bark. Chlorosis—W hen the defect of the due action of both the absorbent and secerning vessels of the liver affects women, and is attended with obstruction of the catamenia, it is call- ed chlorosis ; and is cured by the exhibition of steel, which restores by its specific stimulus the absorbent power of the liver; and the menstruation, which was obstructed in con- sequence of debility, recurs. Indigestion, owing to torpor of the stomach, anda con- sequent too great acidity of its contents, attends this disease ; whence a desire of eating chalk, or mari. Sometimes a great quantity of pale urine is discharged in a morning, which is owing to the inaction of the absorbents, which are distri- buted on the neck of the bladder, during sleep. The swell- ing of the ankles, which frequently attends chlorosis, is another effect of deficient action of the absorbent system; and the pale countenance is occasioned by the deficient quantity of red globules of blood, cansed by the deficient 3 quantity q x ‘ Memoirs of Erasmus Darwin, M.D. 331 quantity or acrimony of the bile, and consequent weakness of the circulation. The pulse is so quick in some cases of chlorosis, that, when attended with an accidental cough, it may be mistaken for pulmonary consumption. This quick pulse is owing to the debility of the heart from the want of stimulus occasioned by the deficiency of the quantity, and acrimony of the blood. . M. M. Steel. Bitters. Constant moderate exercise. Fric- tion with flannel all over the body and limbs night and morning. Rhubarb five grains, opium halfa grain, every night. Flesh diet, with small beer, or wine and water. The disease continues some months, but at length subsides by the treatment above described. A bath of about eighty de- grees, as Buxton Bath, is of service; a colder bath may do great injury. Cardialgia.—Hearthurn originates from the inactivity of the stomach, whence the aliment, ‘instead of being subdued by digestion, and converted into chyle, runs into fermenta~ tion, producing acetous acid, Sometimes the gastric juice itself becomes so acid as to give pain to the upper orifice of the stomach ; these acid contents of the stomach, on falling on a marble hearth, have been seen to produce an efferves- cence on it. The pain of heat at the upper end of the gul- Jet, when any air is brought up from the fermenting con- tents of the stomach, is to be ascribed to the sympathy be- tween these two extremities of the cesophagus rather than _to the pungency of the carbonic gas, or fixed air; as the sensation in swallowing that kind of air in water 18 éf'a dif ferent kind. M. M. This disease arising from indigestion is often very pertinacious, and afflicting ; and attended with emaciation of the body from want of sufficient chyle. ‘As the saliva swallowed along with our food prevents its fermentation, as appears by the experiments of Pringle and Macbride, some find considerable relief by chewing parched wheat, or mastic, or a lock of wool, frequently ina day, when the pain oc- curs, and by swallowing the saliva thus effused ; a tempo- rary relief is often abtained from antiacids, as aerated alka- line water, Seltzer’s water, calcareous earths, alkaline salts made 532 Memoirs of Erasmus Darwin, M.D. - made into pills with soap, soap alone, tin, milk, bitters. More permanent use may be had from such drugs as check fermentation, as acid of vitriol ; but still more permanent relief from such things as Thvioearel the digestion, as a blis- fer on the back; a due quantity of vinous spirit and water taken regularly. Steel. Temperance. A sleep after dinner, A waistcoat made so tight as slightly to compress the bowels aud stomach. A flannel shirt in'winter, not in summer. A less quantity of potation of all kinds. Ten. black- pepper- torns swallowed after dinner. Half.a grain of opium twice aday, oragrain, The food should consist of such things as do not bcaly ferment, as flesh, shell-fish, sea-biscuit, toasted cheese. I have seen toasted cheese brought up from the stomach 24 hours after it had been swallowed, without apparently having undergone any chemical change. Strabismus.—Squinting is generally owing to one eye being less perfect than the other; on which account the pa- tient spicaiule to hide the worst eye in the shadow of the nose, that his vision by the other may not be, confused, Calves, which haye an hydatide with insects inclosed in it in the frontal sinus on one side, turn towards the affected side ; because the vision on that side, by the pressure of the by duties becomes less perfect ; and the disease being recent, the animal turns round, expecting to get a more distinct view of objects, In the hydrocephalus internus, where both eyes are not become insensible, the patient squints with only one eve, and views ovjects with the other, as in-common strabismus. In this case it may be known on which side the disease ex- ists, and that it does not exist on both sides of the brain ; in such circumstances, as the patients I believe never re- cover as they are now treated, might it not be adviseable ta perforate the cranium over the ventricle of the affected side 2 which might at least give room and stimulus to the affected part of ms brain ? M. M. If the squinting has not been confirmed by long habit, and one eye be not much worse than the other, a piece of gauze stretched on a circle of whale-bone, to cover the best eye in such a manner as to reduce the distinctness of is Memoirs of Erasizus Darwin, M.D. 333° of vision of this eye to a similar-degree of imperfection with the other, should be worn some hours every day. Or the better eye should be totally darkened by a tin cup covered with black silk for some hours daily, by which means the better eye will be gradually weakened by the want of use and the worse eye will be gradually strengthened by using a“ Covering an inflamed eye in children for ee pipethien is very liable to produce squinting, for the same reason. — Asthma humorale.—The humoral asthma probably con-: sists in a temporary anasarca of the lungs, which may be owing to a temporary defect of lymphatic absorption. Its cause is. nevertheless at present very obscure, since atem- porary deficiency of venous absorption, at the extremities of the pulmonary or bronchial veins, might occasion a similar difficulty of respiration. Or it might he supposed, that the lymph effused into the cavity of the chest mght, by some additional heat during sleep, acquire an aérial form, and thus compress the lungs; and on this circumstance the re- lief, which these patients receive from cold air, would be readily accounted for. The paroxysms attack the patient in his first sleep, when the circulation through the longs in weak people wants the assistance of the hea power. And hence the eae ents of the lungs are less able to fulf] the whole of their duty. And part of the thin mucus, which is secreted into the air-cells, remains there Bees and oceasions the dificalt respiration, which awakes the patient. And the violent exertions of the muscles of respiration, which suc- ceed, are excited by the pain of suffocation, | for the purpose of pushing forwards the blood through the compressed ca- pillaries, and to promote the absorption of the cffused lymph. In this the humoral differs from the convulsive asthma, as in that there is probably no accumulated fluid to be ab- sorbed; and the violent respiration is only an exertion for the purpose of relieving pain, either in the lungs or in some distant part, as in other convulsions, or ae: y¥3 and in this respect the fits of humoral and convulsive asthma essen- tially differ from each other, contrary to the opinion X= pressed without sufficient consideratign. The $34 Memoirs of Erasmus Darwin, M.D. The patients in the paroxysms both of humoral and con vulsive asthma find relief from cold air, as they generally rise out of bed, and open the window, and put out their heads ; for the lungs are not sensible to cold, and the sense of suffocation is somewhat relieved by there being more ox-. ygen contained in a given quantity of cold fresh air, than in the warm confined air of a close bed-chamber. I have seen humoral asthma terminate in confirmed ana-'’ sarca, and destroy the patient, who had been an excessive drinker of spirituous potation. And M. Savage asserts, that this disease frequently terminates in diabetes ; which seems to show, that it is a temporary dropsy relieved by a great flow of urme. Add to this, that. these paroxysms of the asthma are themselves relieved by profuse sweats of the up- per parts of the body, which would countenance the idea of their being occasioned by congestions of ae in the lungs. The congestion of lymph in.the lungs from the defective absorption of it is probably the remote cause of humoral asthma; but the pain of suffocation is the immediate cause of the violent exertions in the paroxysms. And whether this congestion of lymph in the air-cells of the lungs in- creases during our sleep, as above sugeested, or not; the pain of suffocation will be more and more distressing after some hours of sleep, as the sensibility to internal stimuli increases during that time. For the same reason many epi- leptic fits, and paroxysms of the gout, occur during sleep. In two gouty cases, complicated with jaundice, and pain, and sickness, the patients had each of them a shivering fit, like the commencement of an ague, to the great alarm of their friends; both which commenced in the night, I sup- pose during their sleep; and the consequence was a cessa- tion of the jaundice, and pain about the stomach, and sick- ness; and instead of that the gout appeared in their extre- mities. In these cases I conjecture, that there was a me- tastasis not only of the diseased action from the membranes of the liver to those of the foot; but that some of the new vessels, or new fluids, which were previously produced in ihe inflamed liver, were translated to the feet during the culd fit, ’ “Memoirs of Erasmus Darwin, M.D. 8335 fit, by the increased absorption of the hepatic lymphatics, and by the retrograde motions of those of the affected limbs. This I think resembles in some respects a fit of humeral asthma, where stronger motions of the absorbent vessels of the lungs are excited, and retrograde ones of the corre- spondent cutaneous byanp hanes : vale ence the violent sweats of the upper parts of the body only are produced ; and for a time the patient becomes relieved by the metastasis and eli- mination of the offending material by sensitive exertion. M. M. To relieve the paroxysm a tea-spoonful of ether may be given mixed with w ater, with ten drops of laudanum, to be repeated three or four times. Vencsection. An emetic. A blister. Afterwards the Peruvian bark, with a grain of opium at night, and two or three of alocs. A flannel shirt in winter, but not in summer. [ssucs. Digitalis ? In this species of asthma, there is great reason to believe, that the respiration of an»atmosphere, with an’ increased proportion of oxygen, will prove of great advantage; some well-observed and well-attested eases of which are published by Dr. Beddoes; as this purer air invigorates the circulation, and the whole system in consequence, perhaps not only by its stimulus, but by its supplying the material from which the sensorial power is extracted or fabricated. In spasmodic asthma, on the contrary, Dr. Ferriar has found undoubted benefit from an atrnosphere mixed with hydrogen. Partwritio.—Parturition is not a disease, it is a natural process, but is more frequently unfortunate in high life than amongst the middle elass of females ; which may be owing partly to fear, with which the priests of Lucina are liable to imspire the ladies of fashion to induce them to lie-in in town; and partly to the bad air of London, to which they. purposely resort. There are, however, other causes, which render parturi- tion more dangerous to the ladies of bigh life; such as their greater general debility from neglect of chereente exercise, tbeir inexperience of the variations of cold and heat, and their seclusion from fresh air.. To which must be added, that oreat source of the destruction of female grace and beauty, as well as of female health, the ticht stays, and other 336 Materials 3 for a History of the Pr ussidtes. Gi other bandages, with which they are: sepclhn tortured irt their early years by the active folly of their friends, ‘lied by displacing many of the viscera, impedes their actions, and by compressing them together produces adhesions of. One part to another, and affects even the form and aperture of the bones of the pelvis, through which the nascent child mast be protruded. As parturition is a natural, not a morbid process, no me- dicine should be given, where there is no appearance ‘of dis- ease. The absurd custom of giving a powerful opiate-with- out indication ‘to all women, as soon as they are deliveredy is, I make no doubt, frequently attended with injurious, and sometimes with fatal consequences. Another thing very injurious to the child, is the tying and cutting the navel-string too soon; which should always be left till the child has not only repeatedly breathed, but till” all pulsation in the cord ceases. As otherwise the child is much weaker than itought to be; a part of the blood being left in the placenta, which ought to have been in the child ; and at the same time the placenta does not so naturally col- Japse, and withdraw itself from the sides of the uterus, and is not therefore removed with so much safety and certainty. [Fo be continued. ] - XLIX. Materials for a History of the Prussiates. By M. Provust*. t Prussian blue used in commerce is rarely pure. Scheele has already uoticed this fact. We often find in it, besides alumine, which forms part of it, silex, carbonate, and cal-: careous sulphate, sulphate of potash, phosphate of iron, the - red oxide of this metal, sulphur, coleaginous ammonia, &c. In order to comprehend the nature of this combination, it. is indispensable to use a prussiate without alum, suf- ficiently washed in the acids and in boiling water. It even appears from a remark of Berthollet, that the prussiate * Annales de Chimie, tome lx. p- 185. of 7 Materials for a History of the Prussiates. 337 of potash may be attached to Prussian blue, so strongly as to resist the washing to a certain degree. [ do not think with him, however, that the surplus of this salt should be considered as an element essential to it, for the Prussian blue which has been well prepared, leaves no trace of saline matter in the residue of its distillation. : Prussian blue, prepared without alum, is cupreous like fine indigo. It loses 0°45 only by combustion. Its residue is red oxide without any mixture of extraneous matters. Action of the Alkalis.—Prussian blue, when tried with causti¢ potash, leaves a residue which is only red oxide con= founded with alumine. The shade is that of kermes, if the blue be of a good quality: on the contrary, it is pale and earthy if it has been surcharged with alumine; so that we may jodge of its nature extremely well from the colour of _ the residue. _ -Theacids, when applied to’ a residue’ properly washed, extract no colour from it: this shows that we may in a single operation rob the Prussian blue of all its acid; but for this purpose it must be finely pulverized, which is ex- tremely difficult to accomplish. If we throw some drops of alkalt into water_coloured by blue freshly precipitated, the colour is completely discharged: in this case the oxide sepa- rated from it dees not give the least vestige of colour when we moisten it with an acid. In the process usually followed, it frequently happens that the ochrey residue preserves either some residue of blue which has not been attacked by the alkali, or a mixture of prussiate of potash, and of ferru- ginous alkaline carbonate, or even these three substances confounded together. I shall now examine two of these cases ; the third may easily be guessed at. | If, for instance, we try an acid upon a residue well washed, and which still retains some blue, this last will not be dis- . covered in pulverulent particles, except in proportion as the acid will free 1t of yellow oxide. Between this oxide and Prussian blue there is no particular chemical union, as has been hitherto supposed ;) at least there is nothing which po- sitively indicates that the salino-metallic combination, which we call prussiate of tron, is, like so many ‘others, susceptible Vol. 32. No. 127. Dec. 1808. Y of $38 _ Materials fora History of the Prussiates. of a maximum and minimum; aud if the mixture of yellow and blue sometimes presented to us by these residues is not ‘green, as might be expected, it is because the yellow oxide always covers these remains of blue in a very great excess; at least I never found the Jatter to’ exceed one or two. hun- dredth parts. ‘IT now proceed to the band case. A residue, if etl pulverized, may contain no vestiges of blue, but it easily retains the two salts mentioned ip If we apply an acid to it in this state, both give blue in abundance. We shall by and by examine the particular mixture of these two salts ; but if it has been carefully washed, the acids can no longer produce any salts from it. Indeed, nothing is more tedious than this washing, ‘for I was obliged to. renew the boiling water at least 20 times successively upon a single drachin of residue before I obtained it completely pure : but when we at last succeed, the acids dissolve it without giving blue” When these residues eflervesce with the acids, it is be- cause they contain carbonates of potash or of lime. By washing, the first is carried off; by the application of vinegar after washing, we discover the second. Thus it is not the red oxide which occasions this effervescence: it is not sus- eeptble of being combined with the carbonic acid ; it cannot therefore take it from potash in exchange for the prussic acid which it receives from it. Im nature, as well as in art, the oxide of iron at the minimum sae may be united with carbonic acid, One pound of blue of commerce 2 of a fine quality gave nearly nine ounces and a half of crystallized _prussiate of pot-. ash. IJtis by no means rare to find in the mother waters, when left to themselves, truncated octahedrous’ one inch in’ diameter:'. When this blue carries sulpburie acid with jit, there must be at least four crystallizations, in order to purge the prussiate of the whole sulphate of potash. These mother waters contain alumine sometimes in abundance, sulphate and phosphate of potash, fcrruginous alkaline carbonate. By -this we may judge why, in analyses, it is of importance to use crystallized prussiate, and not simple lixiviums of Prus- sian blue, as formerly made," The prussiate of potash is unalterable Materials for a History of the Prussiates. - 339 unalterable in dry or humid air: the longest continued ebul- lition does not alter its nature in the least: the taste is sweetish, slightly saline, and leaving a sensation of bitter- ness behind: aleohol does not aera it. If we mix some of it with a solution, the prussiate is separated like white flakes of snow, which preserve their lustre when-dried, and resembling the silvery kind of gauze presented by the: ace- tate of mercury. When ids in water, it reproduces an ordinary solution of triple prussiate. This salt, which I shall denominate friple to distinguis it from the simple prussiate of potash, is equally constant» in its attributes with the most perfect neutral salts. “Iris of ‘a fine citrine yellow colour, which never leaves it until 1t changes its state: for this colour, as well as-for its two other characteristic properties, cf crystallizing and dyeing the red oxide blue, it is indebted to a portion of black oxide, which forms an essential part of its constitution. Without this.ox- ide, subjected, like the two other elements of the triple prus-. . siate, to an invariable propertion, this prussiate could in fact neither crystallize, nor form blue with the solutions of iron, the base of which was at the maximum. It is, in short, from) this very union that the principle which saturates the potash of the triple salt extracts, as remarked by Berthollet, proper-. ties which singularly increase its analogies with the acids. In this view we may add, that the triple prussiate eccupies the middle between the alkaline and the metallic salts. When we reflect, however, upon one property of this salt, which we shall mention presently, it would-be difficult: to ascertain whether it is to the prussic acid, or to the simple prussiate collectively, that the oxide of iran attaches itself when itis. raised to the state of triple prussiate. What is certain, how- ever, is, that we are still ignorant of what aspect or what properties a prussic acid should have, which should be united m precisely a proper. proportion with that dose of black oxide, by the assistance of which it can furnish a triple ageeiseas On treating the prussic acid with this oxide, we. may make Prussian blue, but not the Ginenons nae of acid, which is proper for converting potash inte triple salt: this must not be lost sight of; for we know yery welt that Yo Prussian 340 Materials for a History of the Prussiates. Prussian blue is not of a nature t6 be combined without a residue with potash. Tn a word, the triple prussiate, with — the exception of its alkaline base, is, if I may so express myself, a compound as to which we have as yet no datay and no idea which authorizes us to consider it’ rather as a salt, the acid of which would have been particularly exalted by its union with the oxide, than as a combination perfected throughout all its parts by this same oxide. One property which seems to hinder us from admitting? the prussiate as a salt, the acid of which should. be exclu- sively united to the black oxide, is that of its resisting the power of the alkaline hydro-sulphurets. If these re-agents, which spare no other metallic salt, have no action upon the triple prussiate, we are therefore to a certain extent) war- ranted in presuming that the oxide of iron could: not’ well have been exclusively attached to the acid of the triple prus- siate, unless we are willing to believe that the affinity of this acid for the oxide is not powerful enough to defend , it from the fate which is common to all the other oxides. . To’ conclude: We shall see presently that an affinity so extra- ordinary, however unexampled it may’ be in chemistry, 1s not an impossibility. I shall now proceed to the trial of the hydro-sulphuret of potash upon the triple prussiate. Hydro-sulphuret and triple Phosphate.—The hydro-sul- phuret of potash or of ammonia, even when assisted by heat, has no action upon this salt.. If it contained some remains of ferruginous carbonate, it would be freed from it, because the hydro-sulphuret decomposes the Jatter: we may filter it if necessary, and yet the prussiate still crystallizes under the accustomed form. A similar result leads us to discover, as we originally insinuated, a most particularly intimate com- bination between the three elements of the triple prussiate. But we shall see these same hydro-sulphurets contribute in enabling us to’ obtain, in all its purity, the white prussiate, . or that union in which the iron is at its minimum of oxida- tion, which I proved in my first memoir upon Prussian blue. White Prussiate.—On the one hand we must have a flask of green sulphate very much diluted, at the bottom of which we keep some grains of sulphuret of the same metal, . in Materials for a History of the Prusstates. 341 in order to preserve its base at its minzmum. On the other hand, we keep in ebullition over a lamp, a matrass, in which has been placed fifteen or eighteen grains of prussiate of pot- ash and two or three ounces of hydro-sulphureted water: a few seconds after the ebullition or the vapour of it has driven off the air which occupies the vacuum of the matrass, we drop into it some solution of the sulphate: there is a precipitate immediately produced which makes the liquor as white as milk, and which remains so while the heat con- tinues. This is the precipitate which I call white prussiate: this is the prussiate obtained by Fourcroy, Vauquelin, Davy, and all those, without doubt, who, having had regard te the conditions which secure the success of it, have ascer- tained that the base of the green sulphate could also become the base of a prussiate different from that which has for its base the oxide at the maximum. But as upon passing froma one combination to the other the black oxide does not al- ways lose its disposition to be hyper-oxidated, we see that as soon as the matrass is removed from the fire the atmosphere reacts upon the milky-looking mixture, and rapidly ex- hibits undulations in it which commence by shading it, and which finish by giving it the deep shade of the most perfect blue. ( : We may also obtain this product in another manner. Drop some grains of prussiate of potash into a very dilute and boiling solution of green sulphate, and we see a preci- pitate appear, the white of which sustains the action of the air for a short time longer. : The following are a few additional processes, which, if they add nothing to our conviction, are nevertheless inter- esting from the variety of the means. Fill two glasses, one with nitrate of iron and the o' other with green sulphate, both very dilute: afterwards drop into thera a crystal of prussiate of potash. In the first we find ° the crystal is coloured at the same instant of so deep a biue that it resembles black velvet. In >the second it crackles, disperses, and falls down in a white powder: but, as before becoming the subject of the experiment it had imbibed at- Ya3 mospherié Hoy Sin 342 Materials for a History of the Prusstates. Vi mospheric.air, the precipitate resulting from it. assumes the appearance of a piece of parsley cheese. tH Will two glasses. with boiling water: put a few. ite a prussiate into the one, and an equal quantity into the se- cond: add to the latter some drops of hydrosulphuret of potash or of ammonia. These two glasses being thus pre- pared, drop some nitrate of iron into them : the first yields, as might be expected, a complete blue ; but the second pre- sents the amusing spectacle of a. precipitate. which, al- though blue at first, rapidly quits this colour to. become white, The theory of these facts is so evident that 1 shall not dwell upon it, nor shall I repeat all the other experi-" ments mentioned in my first memoir, in order. to establish the existence of the two prussiates of iron. If the prussiate at the minimum has no colour when it 1s not affected by the atmosphere, we find that the green sulphate when dried. has none also. The absence of colour in one of these salts is surely not more astonishing than its absence inthe other; and finally, if we obtain red oxide by applying. the alkalis to the blue prussiates, it 1s on the contrary black. oxide which we extract from the white prussiate, But these dif- ferences, which theory previously points out, perfectly co- incides with those exhibited by the red and green sulphates under similar circumstances. Jn my first memoir I advised the pouring of the prussiate of potash upon the sulphate in a flask, in order to.avoid, as much as possible, the- mixture of the air, but T succeeded very imperfectly: mm the first place because cold. liquids al- ways bring some air along with, them; and «secondly, be- \ cause I had not thought of sulphuretted ‘bdanedee for purog them. I was not then acquainted with the way in which it acted with these salts. ~ If, for example, we dilute the solution of green olin with three or four times its volume of sulphuric or muriatic acid, the excess of these acids docs not in the least change the result. The white prussiate only wanting colour on ac-~ count of the want of oxygen, we should think that additions like these are not made for the purpose of giying it. Acids £ _ more Materials for a History of the Prussiates. 343 more concentrated may alter the whiteness of the prussiate, but will never bring it to a perfect blue. : The marine acid, boiled c over prussiate also does not make it blue. This boiling acid is not without, action upon the white prussiate. The following is what I remarked on this subject : Some white prussiate is -destroyed, some prussic gas disen- gaged, and we find black oxide in solution: im this case‘ the little Prussian blue formed by the introduction of the air during the interval of the mixtures, predominates over the white, aid changes 1 its whiteness to greenish. The blue ian boiled Sith the same acid, also gives prussie gas and abandons red oxide, but less is destroyed of it than white prussiate. We may infer from these facts that the muriatic acid, aided by heat, could, strictly. speak- ing, decompose the prussiates, and resume over the prussic its rights asa more energetic acid :—this would not be an astonishing, but it would be at least a tedious, experiment. Prussiate of Potash and Acids.—Heat marine or weak sulphuric acid in a matrass with crystals of prussiate. When ebullition commences, the gas escapes; let it be received in a bell-glass full of mercury, or burn it by presenting the flame of a candle to it. The flame it emits is variegated red, violet, and yellow: during the dissipation of the gas, the liquor is thickened by the production of a white precipitate, which passes to the blueish. ~The gas being totally separat- ed, throw the mixture into -boiling water, revive with oxy- ~genated muriatic acid; wash and dry the product in a cap- sule. Four experiments, made at distinet periods, yielded me from 0°34 to 0°35 of complete blue, for a hundred eos of triple prussiate. nese Inferences—100 parts of Prussian blue, without alum, yield 0°55 of red oxide by combustion, This same blue destroyed by the nitric acid also gives 54. Thus then itis, no- doubt, that pure blue of Prussia only contains from 0-54 to 0°55 of red oxide. According to these data, 0°35 parts of blue should render about 0°17 of black oxide, or 0°19 of red oxide. Hence it follows,,when we formerly separated the iron of asolution by the prussiate of potash, this salt added Y4 to 344 Materials for a History of the Pr ussiates. to the product the 0:19 of red oxide, which resulted from its. own decomposition: but the surplus was still greater when, instead of crystallized prussiate, we used a simple’ al- kaline lixivium of Prussian blue. We shall see the reason of this presently. When we pass a ley of common potash over Piecksdn blue, a part of the alkaline carbonate is charged with red oxide; there. results a solution which. answers to Stahl’s. martial tincture, and of which pure potash is not susceptible. Tins solution, which may be also prepared by throwing some | drops of nitrate into liquid carbonate, may be mixed with the prussiate of potash without occasioning the least change even by remaining init. It is this same ferruginous ear- bonate which, as I have said, is recovered in its mother waters. Now if we add an acid to the mixture of these salts, we precipitate perfect blue from it, because the new solution of oxide which replaces the eategoty | carbonate decom- poses in its turn the prussiate of potash, as any solution of iron would do*, : The instant, therefore, that we employ in any analysis a prussic lixivium in place of a crystallized prassiate, we do mothing else than add to the product; in the first place, the red oxide, which formed part of the ierruginous carbonate, hen the black oxide which 1s-a constant element of the triple prussiate contained in this lixivium. Chemists very soon discovered the vicious effects of these lixiviums, although they did not at first perecive that they contained two very diferent ferruginous com- binations : the carbonate already mentioned, and the triple prussiate. Several experimenters, even when they gaw the biue they furnished with the acids, thought this blue -was natural, or, in other words, oxide or blue of Prussia ; they endeavoured to precipitate it, however, without, touch- ing the alkaline prugstate, which they thought to be endow- ed with-the property of dyeing without owing it to the iron. From iheir-efforts arose the recipes for precipitated Jixiyiums which we find in every book upon chemistry. But gince ““sIt is the mixture of these same salts which prepares the mother waters of soda, for giving P.ussian blue when we add an acid to thems) ° ©!) ff hy the ~ \ Materials for a History of the Prussiates. 345 the inquiries of Scheele and Berthollet, we have ascertained that these recipes but. imperfectly fulfilled the object im view : for it is easy to see that it was not enough io stripa lixivwam of the oxide which the carbonate introduced into it: it still remained .to provide against the black oxide which belongs to the triple prussiate, and which we might so much the less suppose to exist, since the addition of the acids, with- out the intervention of light or of heat could not render sen- sible the products of its decomposition. I shall not stop to analyse the phenomena presented du- ring the preparation of the hot or cold lixiviums; because, now that we are well convinced of the inutility of the prussiates with respect to tlie evaluation of the quantity of iron in ana- lyses, the details are of little interest; for the same reason [ pass over the liquid tests proposed with ammouia, chalk, mag- nesia, &c., because they are themselves triple prussiates, in which we cannot place confidence, unless weemploy them in the same way as the counter-proof proposed by Berthollet. I shall add, only because it is a fact worthy of being re- corded in the history of science, that, when the chemist would stilt take advantage of a lixivium er liquid test, which he had purified by means of an acid, we may be assured he has not attained (as he pernaps flattered himself,) the com- plete separation of the iron ; for it is certain that every lixi- vium which gives a blue colour with a solution of red oxide, contains also black oxide, since without the «assistance of the same oxide it could not be dyeing prussiate: or, in other words, every prussiate of potash, which has not been tripled ! (trisulé) by the black oxide; consequently prussiate of potass, when pure and simple, is not capable of forming blue with a solution where the oxide is at the maximum i— this has occurred to those most experienced in analytical pro- cesses. [tis a truth which Scheele has perfectly established. ] repeat, therefore, that the saturated lixiviums or the al- kaline prussiates cannot really serve as'a dyeing (¢etgnant) re- agent unless a portion of black oxide has rendered them triple salts, the red oxide being by no means capable of supply- ing the place of the black oxide for this purpose. Finally, wemay conclude from all these circumstances that the:al- kaline 346 Materials for a History of the Prussiates. bh kaline prussiates or earthy triples should not for the future en- ter into the class of reagents useful in analyses, for this plain reason, that they. cannot discover the iron in any: solution, without, at the same moment, adding their own: they ought only to be allowed to.make a figure among. those which, like turnsole gall-nuts, &c., are confined to the class of reagents proper for indicating antral) if such and such | a ae be presented. Diluted sulphuric acid, when applied to the tiple prus- siate, furnishes similar results with the murtatic. 100. parts of prussiate restore by this method from 115 to 116 of sulphate of potash. Jf we knew exactly how much’ al- kali there is in the sulphate, we might infer from. the esti- mate the base of the prussiate of potash. 100 parts of crystals of prussiate lose ten of water by distillation. In order to complete its decomposition by the acids, the ‘ebullition must be kept up at least half an hour, in order to dissipate the gas entirely, and to obtain the complete sepa- ration of the white prussiate which is formed during the operation. The prussiate of dala is dissolyed cold in the muniatic acid, without being decomposed.. This mixture requires, according to Berthollet, the assistance of light or of heat. Vinegar assisted by ebullition also decomposes it; the prussic gas escapes, and the white prussiate is formed; it does not become blueish so rapidly as with the foregoing acids: im short, this prussiate, which does not appear ex- cept at the very moment when the ternary combination be- gins to be disorganized, strongly confirms. by its whiteness that it is really the oxide at the minzmum only, which has the’ privilege of entering into the formation of the triple prus- siate : this is one of those truths which Scheele has com- pletely established. Notwithstanding this, however, the distinction of the oxides in these circumstances is a point to which. subsequent chemists have not paid sess at- tention. Black Oxide Blewett of Rinrsiue Blue.—We heal nlow prove that this oxide, in an invariable dose, is an’ essential principle in the constitution of the triple prussiate ; but. it is Materials for a History of the Prussiates. 347 is a point which also deserves'some attention, when we see that this same oxide can follow the prussic acid from one combination to the other, without changing its state: when we see also this oxide pass from prussiate to prussiate, re- turn from the latter to the former, circulate through even the most oxidizing medium, without thereby losing the state which constitutes it anoxide at the minimum :.this is also a point in the history of prussiates, which in my opinion has not been attended to, If, for example, it would be correct to say, that without the assistance of the black oxide the prussiate of potash would neither be yellow, crystallizable, nor dyeing, we might assert with equal truth, that the Prussian blue could not be formed without the intervention of this same oxide ; and in fact when, with a solution of red oxide of triple prus- siate of potash, we make Prussian blue, the black oxide ,of ihis salt passes jointly with its acid into the new combina- tion: whence it follows that this oxide, element of the prus- siates of potash, becomes so afterwards from the Prussian blue, and even as-we shall show from all the other metallic prussiates which are formed with this salt. one _ This black oxide is found so solidly interwoven in the combination of Prussian blue, so well guarded by its al- Jiance with the prussic acid from all ulterior hyper-oxida- tion, that we never fail to recover it in this blue, such as it was formerly in the triple prussiate of potash. I shall go further : if we make blue with this prussiate and the green sulphate, the oxide of this last will rise, as we know, to its maximum, i proportion as the blue will be coloured by the impression of the air; but will it be the same with the black oxide which passes jointly with the acid in. Prussian blue ? Certainly not. This oxide willnot renounce the quality of minor oxide which it had in the prussiate of potash: 7. e. if during the exposure to the air the base of the green sul- phate, and consequently that of the white prussiate, is raised from 28 to 48 per cent., the black oxide, the inseparable attendant upon the prussic acid, will not participate in this hyper-oxidation, it will invariably keep to its 28 per cent. Not only the atmosphere, which so easily raises ‘to their maximum 343 Materials for a History of the Prussiates. moximum the bases of the'sulphate, of the muriate, and of ' the white prugsiate, loses all its activity with respect’ to the . bldek oxide in questione but still, neither the application of the boiling nitric acid, nor the oxygenated muriatic acid, can succeed In raising the oxidation of this last. These acids may in fact destroy Prussian blue, and even reduce it to red oxide: but while there remains some blue to be destroyed, this last will preserve to the end the black oxide in all its primitive integrity. If we treat the red oxide with ace acid, we shall ae no kind of combination ;—this is conformable to the obser- vation of Scheele’: but if we make use of black oxide, we shall obtain greenish prussiate which the air will convert mato perfect blue. The black oxide enters therefore into the combination of Prussian blue. If this oxide was not necessary, or if the red oxide could exclusively serve asa base to Prussian blue, we do not see why this oxide, and even its solution, mixed with simple prussiate of potash, would not give-Prussian blue. I have remarked a Jitthe higher that the affinity of the prussic acid for this dose of black oxide, which renders it proper for producing triple prussiate, might be powerful enough for saving it from the destiny common to all the ox- ides which are combined with acids m general. Tt appears to me, in short, that we draw this consequence from the following experiment : Throw into a flask hydrosulphuret of potash upon Prus- sian blue, and keep the mixture well corked: in a few days -we find the bydrosulpburet converted into triple prussiate, and the red oxide of Prussian blue alone changed into black hydrosulphuret : and hence we see that if the red oxide has followed the example of all the oxides when the hydrosul- phuret finds them united to acids, it is not so with the black oxide, which, as we have so frequently said, passes from the triple prnssiate of potash into the Prussian blue. This oxide, as it were, forms a separate stripe; it never participates in the changes of which the red oxide is sus- ceptible, which is the base of Prussian blue, Hydro-sulphuretted water brings the! Prussian blue to ithe ~ state _ Materials for a History of the Prussiates. 349 state of white prussiate, as it does. the red ‘sulphate. | ‘This’ fact I have published in my first memoir; ‘and the power ‘of this reagent neveripasses beyond 5. but) thé: hydro- -sulphdret of | orth totally changes the red-and’ green’ sulphates imto black hydro- -sulphureted oxide. Why cannot: the! hydro sulphuret extend its action to the’ black oxide in question ? There must be 4 singular affinity, and of which there are” few examples'in chemistry, which enables: the prussic acid): the weakest of the acids in so many respects, to protect this oxide: against the whole power of ‘the gel meg sulphurets.) -/«: ime ak All the metallic solutions which give prussiates with the, triple prussiate of potash, certainly follow the example of those of iron. The prussiates resulting from it will preserve in all its purity. the.black oxide which the prussic acid car~, ries with it. Buteit is now time to lay before’ my ‘readers: the grand experiment which demonstrates | that Prussian blue is a triple salt, and that the black oxide, which’ had passed from the triple prussiate of potash into the Prussian blue, may still repass from the Prussian blue ito the potash, without having at any moment Se las its quality of oxide at the minimum. ~ : I presume that this experiment is already anticipated by those who have conceived'a clear idea of the: nature of the triple prassiate of potash. Take a Prussian blue, for instance, which has undergone all the reactions which the atmosphere or the most bishly oxidating acids may have produced upon it. Apply pure potash to it, and we shall procure a lixivium, which will.oniy give triple prussiate, 7. e. a cornbination in which we shal! find the prussic acid constantly associated with the common dose of black oxide. If this prussiate is really what I have described it to be, which the reader can scarcely doubt, there will be no objection, I think, against the new point of the- ory which establishes * that the white or blue prussiates are triple combinations, as well as the prussiate of potash which has concurred to their formation.” From the potash of oa of manganese there results erystallizable triple prussiate of potash, yellow, and provided with 350. Materials for a History of the Prussidtes. with all its black oxide. This prussiate of manganese 1s therefore also a combination tripled (¢risulée) by the black ‘oxide : the prussiate of copper, which is of a blood-red co- lour, is, without doubt, another combination of it, for the simple prussiate of copper is yellow. as Scheele assures us, that other oxides have also_ the pro=: perty of trebling (de trisuler) the simple prussiate of potash. It is,a course afi inquiry so much the more interesting, as it is likely to lead to the discovery of some colour equally pre =) cious with that of Prussian blue: and lastly, we may con- clude, from all we have seen, that there exists no simple prussiate ef tron, a kind of combination of which other metals are nevertheless susceptible, as. we shall soon see. Distillation of Prussian Blwe.—TVhis prussiate when ex- posed to a high temperature is destroyed. It is replaced by new products which confirm the theory) given us by Ber-, thollet, upou the nature of the prussic acid. We obtain acid which escapes its destruction, carbonate of ammonia, a little free carbonic acid, and gaseous oxide in abundance : one ounce of (he blue of commerce of a good quality: gave a little more than dwo pints and a half of this gas; what was wanting to complete the three pints was carbonic acid. The water,of the tub, contained prussic acid fixed by am- monia. This prussiate follows, a8. we know, the traces of that of simple potash : it cannot form blue with solutions of red oxide; but it gives them with those of oxide at the mz- nimum, because at the same moment it constitutes itself triple or dyeing prussiate. The residue jveiecliell five drachms 52 grains. [1 was per- fectly black, and answered to the magnet: itis a, pyrophorus which rapidly takes Ure. If, after having preserved it ill corked so long that it cannot take fire of itself, we moisten it with nitric acid at 40 degrees it burns in a very lively manner. I am inclined to think that in this combustion the iran burns jointly with the charcoal. | if Prussian blue has no alum in it, we eee only charcoal and iron in. the residtie. -The muriatic acid extricates from it with the greatest fa-— cility that aromatic hydrogen which announces iron com- bined Materials for a History of the Prussiates. 351 bined with charcoal. The rest is pure charcoal; one of the elements of the acid destroyed. The two others, the hy- drogen and azote, are employed in producing ammonia. As to the carbonic acid and the gaseous oxide, it is equally evi- dent that these are the two oxidations, major and minor, of the charcoal furnished by the oxygen of the two oxides which we have ascertained to exist in Prussian blue. This decomposition takes iplace with such a moderate heat that it has appeared-to me very convenient when we wished to procure gaseous oxide. - There is not the least ground for suspecting any oil to be present : it is very surprising to see that in the course of a destruction where charcoal and hy- drogen abound, there is not.a single particle of these. com=- -bustibles. which proceeds to constitute itself in any of the respects which can form oil. The oily and aromatic character assumed by the hydrogen during the solution of the residue, also demonstrates that the combination of iron with charcoal does not require a very high temperature. The charcoal of the blood when it is obtained by a very inferior heat, also contains iron ina carburetted state ; for with miuriatic acid it also gives aro- matic hydrogen. IJ think Priestley has somewhere noticed the bituminous smell of the hydrogen furnished by the fluxes of charry substances. : Distillation of the triple Prussiute af Potash.—V his salt loses ten per cent of water, and its colour also, for it be- comes bleached; it does not become soft without a red heat being applied. Some chemists have thought they discovered in the roasting or flux of it a method of taking away the oxide. The less results will show that me processes lead to nothing useful : _. When this salt enters into fusion, there escapes a little prussic acid, which is seized by the ammonia formed at the same instant. There afterwards passes over-a nebulous va- pour, which is condensed like farina in the neck of the re- tort.. This yapour is not continued after, when the flux is finished, and the sublimate so formed has the alkaline and bitter taste of the simple prussiate. " Alcohol dissolves a part of it, and what is separated from it ? 452 Materials for a History \of the Prussiates. | it is triple priassiate withoutialteration ; .i. e. the latter | gived Prussian blue with the solutions ofred oe while the sane cannot give anys: oft ; i if we present a lighted candle to the: oe of the> wuhses the prussic acid sites alone, and ‘the carbonic acid | pro- ceeding from its combustion forms with ammonia crystals of carbonate, which are condensed in the neck of the retort a few lines above the flame. Let us now pass to fe examina- tion of the fused prussiate. res os “The mass resembles fused sea-salt : it is’ of an ash-gray, and strongly attracts humidity. | If we taste a piece of it,’ we do not discover the sweet- ness of the triple prussiate, but an alkaline taste perfumed with the bitterness of almond kernel supplies the place. This \aste announces already, that there is simple ‘prussiate of potash in this residae. Some drops of acid liberate a gas which does not belong to this prussiate, and’which suggests the idea that there is carbonate of potash there also. Lastly, this mass when dissolved, deposits a black pow- der like mica, and very brilliant. When collected ‘by ‘thé filter it isa mixture of charcoal,' pure iron, and a little sul- phuret of iron. This last is'an accidental product + its sul- phur proceeds from the aaa Rie of the sulphate of potash, from which it is difficult to purge the triple prus? siate. This powder is attracted by the magnet! A weak acid at first disengages from it sulpliureted hydroven $ : after- wards comes aromatic hydrogen, and im the last place's we only find charcoal powder. Examination of the Solution of the Re shale IN with it ammoderate quantity of alcohol at 25 decrees’; there is im- mediately pois Bie a brilliant kind of siow whieh may be collected by the filter... When dissolved and orystallized, it gives | Vellowish sweetish crystals, which, with muriatic acid, furnish prussic acid and white prussiate. Here we have the prussiate purged from oxide, proposed by M. Richter. - The alecholic solution is distilled almost dry, it is after- wards covered with alcohio] at 30 degrees: une portion of it is then dissolved, and the rest falls tothe ‘bottom. ~The Jatter when examined is carbonate of potash with some re- ™ains yee ae Materials for a History*of the Prussiates. 353 ’ mains of triple prussiate. The.new solution, when distilled, gives simple prussiate, which is known by its taste, and the property of not giving blue with solutions of red oxide. The above are the products which I found after the flux, of the triple prussiate of potash. INFERENCES. The triple prussiate cannot support an elevated tempera- ture without being simplified in its composition. It gets rid of the black oxide, and passes to the state of simple, prussiate: but the latter can also be reduced to something more simple, as we shall soon see: it then leaves potash in, its place, and the ordinary remains of the prussic acid, which are ammonia and charcoal. A part of this last serves for deoxidating the black oxide, 'to reduce it to iron, and its oxygen into carbonic acid. . During these changes a part of the triple and simple prus- siates succeed in subtracting themselves, in proportion, - without doubt, as the carbonate makes them into a paste : but it is hikely that along continued high temperature in strong vessels, would at last reduce these prussiates to two binary combinations, which are ammonia and carbonic acid, with potash, iron, and remains of charcoal, which the oxygen of the iron and the humidity was not able to_acidify. Simple Prussiate of Potash.—It is obtained by saturating after Scheele’s method potash with prussic gas liberated from the prussiates of potash or of mercury ; but it is more expe- ditiously obtained by keepingthe alcohol over a concentrated lixivium of animal charcoal. It must be shaken from time to time, and the progress of the solution is ascertained from the alkaline and bitter taste of the alcohol. The lixiviums of charcoal from blood cr leather are rarely free from a little hydro-sulphuret, because the sulphate which conta- minates the prussiates produces sulphur in them: some then passes into the alcoholic ‘solution; but the charcoal also contributes to it, for I prepared lixiviums with charcoal from blood and very pure carbonate of potash, and yet I found hydro-sulphuret, although in a smaller quantity. [t_ must not be forgotten that sulphur has been already found Vol. 32, No. 127. Dec. 1808. pie in, 354 | Materials for a History of the Prusstates. in the ammoniacal products of the blood. It even seems that, like phosphorus, it cau be fixed in the charcoal, but not in the iron which it contains ; for the smell of the aromatic hydrogen mentioned above gives no indication of | the presence of sulphur. We easily recognise the simple. prussiate te its Satie alkalino-bitter taste, and by the aroma with which it fills the month. It precipitates in yellow the solution of copper, and does not give blue with that of red oxide; but it pre- cipitates them in ochrey yellow, as a pure alkali would do*. Lastly, it gives blue. with an ordinary solution of sulphate of iron, because there 1s at first constituted trinle prussiate : afterwards it gives white or blue prussiate of iron, If the prussiate be black, it is because the alkaline hydro-sulphuret introduces hydro-sulphuretted oxide into it; but we get rid of it with some drops of acid, and the prussiate of iron ap- pears alone. ‘The simple prussiate cannot be well preserved except in a closed flask. Scheele has shown, that the car- bonic acid is sufficient for separating it from the potash while its affinities are fechle; when the black oxide is not united with it, eoncentrated it refuses to crystallize and runs into a mass, in which, however, we distinguish some saline Jamine. ah tae This prassiate is the test liquor proposed by Scheele: Its utility in analysis is not limited, since all solutions. the iron in which is at the maximum, (and this is most fréquent,} are not, as he has himself shown, by any means sensible to - this reagent. In order to employ it carefully, we must bring back to the minimum a part of the oxide of the solutions : this is not always easy, nor without danger of increasing the difficulties of the experiinent. Its Decomposition.—The aqueous solution of this prussiate, on being boiled, abandons a part of its acid : which demon- strates sufficiently ‘that this combination is neither solid. \ * In a memoir I wrote upon Sigena stone, I announced this unien as being probable ; but 1 now find it was a mistake. A sulphate of iron which I had hyper-oxidated by the jaitric acid, and which, nevertheless, retained some. remains of black oxide, deceived me; and Scheele, whom, I contradicted i in this ee saw more clearly than I did. . “, Hop Materials for ad History of the Prussiates. 355 hor comparable to any of those formed by the oxygenated acids. It froths continually, and has something Pamon enue in its appearance. A lighted candle brought nearthe beak of the retort’ burns this portion of acid : but the loss is nct confined to this; the acid which this salt retains more strongly, by the help of the potash which begins to predo- minate, also undergoes by the effects of heat a slow de- struction, which converts it into ammonia and carbonic acid. At whatever period of the ebullition we take the product, we always find carbonate of ammonia in it mixed with a little prussic acid; and latterly, when the water begins to disap- pear, this glenda is condensed in spicules in the neck of the retort. : If we add more water in order to contitiue the ebullition, these same products are found in the water of the receivers But after four or five successive and similar distillations, we cease to perceive them, although the saline residue still con- tains prussic acid in a sensible ideonecs Tt-must then be dissolved with Neate : part of it is dis- solved, and the other totally resists its action. \ In the al- coholic liquor we in fact find prussiate of potash, but the saline mass undissolved is nothing else but carbonate of pot- ash. The object of the two following experiments was to remove all doubt as to the desiruction of the simple prus- siate by the heat of ebullition alone. This prussiate does not disturb the muriate of lime: but that which has undergone a long ebullition precipitates it abundantly in calcareous carbonate. There is a transforma tion therefore of prussiate into carbonate of potash. Two quantities of prussiate, the one altered by a long ebullition, and the other entire, were employed to precipi- tate ordinary sulphate of iron. Both gave a blue colour; but after being revived, the former quantity occupied three times less room than the latter. If we make dry simple prussiate red-hot, there exhales carbonate of ammonia accompanied by an oleaginous vapour resembling that of hartshorn. The saline mass when dis- solved, separates charcoal, and it is still carbonate of potash mixed with some indecomposed prussiate. Z 2 INFERENCES 356° | Materials for a Histor y of the Prussiates. INFERENCES. ¢ All these results certainly bear us out in the ols ule that the simple prussiate of potash is, as Scheele has already discovered, a fragile combination, the elements of which are as easily separated as those of complex combinations. We find, in short, that a part of the acid is removed from the potash by the sole force of dilatation; while the other part, which is longer subjected to the action of calorie, is'de- stroyed in order to be changed into ammonia and carbonic acid. Let us now make the application of this conclusion. The triple prussiate of potash undergoes no derangement by repeated ebullitions. The lixiviums employed in the manufacture of Prussian blue contain, as we shall presently see, friple prussiate and simple prussiate. Besides, there is no ammoniacal saltin them. We are of opinion, that the great excess of carbonate of potash which they contain would not admit of their presence; but they exhale am- monia while in a state of ebullition, From whence could, this ammonia proceed, if it was not from the decomposition of the simple prussiate? We may therefore conclide, that. ‘the boiling or concentration of the lixiviums exposes’ them to be deteriorated by the destruction of this same prussiate, _ which we cannot too much preserve :. and as the carbonate of potash is also one of the principal results of this destruc- tion, it does not cease to add to what is already there. Curadeau was well aware of the deterioration which the boiling of the lixiviums produces, and he very happily pre- cephed the bad effects by adding a little sulphate of iron to them. This is conformable to ‘schele s principle, who has shown that the simple prussiate changes into HD prussiate ag soon as it.can be associated with a portion of black oxide, and thereby be guarded against decomposition. As to the products from the rele st of the prussiate by fusion or by .ebullition, there is certainly nothing extraordinary in them, gince it is suflicient to know the nature of the | prus- sic acid in. order to. prevent them ; but it is not so with re- spect to the carbonic acid which is presented during one of these destructions. Whence comes the oxygen, for example, - which, during the ebullition of the aqueous prussiate, suc- eceds Some Account of aremarkalile Case of Tetanis, 354 ceeds in acidifying the charcoal of the prussic acid? Either this oxygen will be, like hydrogen, azote and carbon, one of the constituents of the prussic, and which is destroyed 5 or it must be supposed that there is a decomposition of water. It is not time yet, as I think, to choose hetween these two opinions; but until we have some more light’on the subject, I shal! say that if we reflect on the circumstances accompanying the production of the prussic acid, we shall adopt in the mean time the opinion of Berthollet in preference to every other hypothesis. ‘It appears difficult,”’ says that author, ‘* to suppose the existence of oxygen in a substance which contains elements so disposed to form peculiar com- binations with it, as hydrogen and carbon are, and which can frequently support ‘so great a degree of heat, without undergoing decomposition.” Ta truth, in order to - admit tha! this acid is an oxygenated product, we ought to suppose that such an acid is capable of disputing ine. oxygen with- the carben which envelops it on all hands, and we cane not do less than place it at the head, not of the acids, but of the oxides, which are known to be the most “difficult of reduction. SSS [ ~L. Some Account of a remarkable Case of Tetanus *. S. C., xt. 22, thin and delicate, a glass-cutter by trade, says, that he accidentally trod on a nail which penetrated the bottom of his foot about half an inch.—It inflamed, ‘contmued painful two or three days, and then healed hit HORE further trouble. ; ‘ Nine days after the puncture, he was attacked with pain in his bowels, with frequent and copious evacuation by stool. This complaint continued till the next day at noon, when it ceased, but left him much weakened by the purging. 11th day.—Still sensible of weakness. In the evening returning from his work he got wet through his clothes. 12th day.—Obliged to put on his wet clothes in the morn- ing; and in returning to his work was again drenched with * Communicated by John Taunton, Esq, i y q , Zz 4, rain, 358 Some Accouni of a remarkable Case of Tetanus. rain. He changed his jacket in the forenoon, but kept the | rest of his wet clothes on the whole day. In the evening he suddenly found a stiffness accompanied. with pain attack the muscles of the neck, extending downwards to the loins, and affecting the muscles round the shoulder so much that he felt much pain on attempting to elevate his arms: he alsa experienced some little difficulty in opening the mouth. He passed a restless night, and the next day, -13th day,—His complaints were more troublesome, though they did not prevent him from following his work, While pursuing it, however, he felt occasionally a:consider- able sensation of weight in his stomach, accompanied with that of a tightness round his body, as if it were giyt or com- pressed by a cord tied tightly round it. He had also much difficulty in bending his body forward.—Little rest at night. 3d day of the symptoms.—The stiffness in the muscles of the trank was now so considerable as altogether to prevent the stooping ;—he also experienced much pain in the part af- fected. Towards evening the pain in the region of the stomach was yery violent, and the, general stiffness more urgent.—His body was (to use hisown expression) as stiff as a poker: and at times he felt his head drawn forcibly back- wards.—In the night he was still more restless, 4th day.—All his complaints were aggravated,—the-re- curyation of the head and spine being more frequent and the stiffness vf the muscles more general. In the evening the sensation of a load at the stomach was so distressing that he took a dose of antimonial wine, but it did not eperate.— His jaw had now gradually so much ¢losed that his food could scarcely be introduced between his teeth Passed a very bad night, and on the 5th day,—Being totally unable to work, he came to the Hospital. He now complains of a stiffness at the lower part of the sternum, with a difficulty in breathing. His mouth is almost closed, the neighbouriug muscles appearing rigid to the eye as well as to the touch, but particularly the ster- no-mastoid of the left side, so that he moves his head to the right with much..more ease than to the left,—He feels no, difficulty in swallowing, but cannot easily get food into his ; mouth, Satine Account of a remarkable Case of Tetanus. 359 mouth.._He last night was seized for the first time with spasms in the back part of the legs, his’ eyes were nearly closed by a glutinous Necharee ep, 78. His countenance is like one wie had taken something too sour for the taste: and he sits fixed as a statue, except that short and sudden spasms at different parts of the body occasionally come over him. In theafternoon his complaints appeared more aggra- vated.—He was plunged into the cold bath, and being cos- tive a stimulating enema was administered and he took 9}. of calomel,—he was also directed to drink freely of sherry wine during the night. 6th day.—Passed a quiet night.»-The clyster soon pro- cured one copious stool.—P. 102. Much heat on the skin. The abdominal muscles very rigid ; hesitation in repeating the cold bath: as the calomel had not operated, its action was invited by another enema, which, however, producing no evacuation, he was again plunged into the cold bath at one o’clock. He has occasionally had an involuntary spasm of the tongue which thrusts it between his teeth, the jaw at the same time closing upon it. After the bath his pulse was 88 and the muscles about the neck were much relaxed.— Cap. vini rubri tbj., cum pulv. cinch. 3j., quotidie. During the day he had slight paroxysms of opisthotonos.—Six o’clock, was again immersed in the cold bath while his body was covered with a profuse perspiration. 7th day.—He passed a quiet night (except that during sleep his tongue was twice or thrice thrust out between. his teeth). He went into the cold bath this morning at eight o’clock in the midst of a profuse perspiration, and was much composed after it, and says he is better. He continues to open his mouth with less difficulty and moves his tongue. The abdominal muscles are tense, particularly the lower part. of the recti, and he occasionally feels spasms, which from his description appear to be in the diaphragm. His appetite, his urine, and stools arevall natural,—has slept nearly three hours this morning. | He went-into the cold bath again this day at one o’clock in the afternoon, and again at six. After ‘this third immersion he became more uncomfortable ; says his muscles are stiffer, those of the belly are extremely rigid Z 4 and 360 Some Account of a remarkable Case of Tetanus. and the region of the. stomach very painful : he therefore took 60 drops of T. opii in a glass of wine. At eight o’clock amost violent spasm of the abdominal muscles.came on, and those of the back were affected to that degree as forcibly to incurvate the spine. Immediately were repeated the opiate draught with 3] eth. vitr. After this he socn fell into a quiet slecp which lasted, with little interruption, for ten hours. sth day.—Ten o’clock——P. 96. Says he is better: still drowsy, and complains of general stiffness, but no pain.—} Cold bath repeated——Ten o’clock mid-day, his pulse moderate, and pains considerably abated;—he has more command over his tongue. At nine o’clock in the evening the spasms of the abdomen rcturned, with less violence, however, than on the preceding evening. The cold bath was immediately had recourse to, and having afterwards swallowed asth. vitr. cochl. parv., tinct. opii gtt- 80, vini 3x., puly. cinch. 5)-> he fell asleep and passed a comfortable night. gih day.—His countenance has in some measure relaxed ele that particular appearance which has been remarked. Tt was determined to endeavour to anticipate the spasms this evening by administering the bath and medicines before the probable hour of their return. - Two or three hours, how- , ever, before that time a very slight exacerbation came on, and after a similar treatment with that Ps yesterday evening he fell into a quiet sleep. 10th day.—After eleyen hours sleep the bath was re- ~ peated this morning, his appetite, &c. remain entire.—P. 89. About eight in the evening the cold bath was repeated with the a opiate arauehe : :—about ten he awoke with a _eireumscribed pain at the bottom of the abdomen on the right side, which was tender and could be covered with the palm of the hand : 60 drops more of opium were given by the: attendant, but the pains increasing, a blister was applied at midnight, and a clyster was ivewe up with 120 drops of T. opii. He now takes daily sherry Tbij.—port tbj., pulv. cinch. 3). .» eth, vitr. 3vj. 3 et T. opit Pena frigid. a et. m. iith day.—An intolerable pain in the epigastric region, with. Some Account of a remarkable Case of Tetanus. 361 with sirangury from the blister, has entircly prevented sleep through the might : this pain was particularly urgent during the latter, part of the day, and the only relict he found was from the continued pressure of his wife’s hand (who. stood by him) on the part. At seven o’clack in the evening he begged to zo to the cold bath ; after the use of which ihe spasm and the pains abated.—His opiate increased to 100 drops. 12th day.—Has passed a good night ; ;—universal suHnes much increased: the pain, nate removed irom the epigas- tric to the inguinal region, was again dispelled by the cold bath. 13th day.—Passed a tolerable night ;—says that the abs dominal pains have descended into his thighs. The mus- cles of his face are in a very slight degree wae from their first state, and the skin of that part is ee ee with a greasy- looking perspiration. His body -is sufficiently opened and his appetite very good. Tn the evening an eruption of the miliary kind was ob- served (this had made its appearance on the 10th day) on his skin,—it was preceded by a pricking sensation; it appeared first in the neck, and now covers the whole body. Opiate. increased to 120 drops, 14th day.—The disease appears evidently to be yielding ; the fern pains of the abdomen having sunk into the Re extremities, and the stiffness of his mie being so far over=_ come that, with very little support, he is able to walk a few paces. 15th day.—He can now walk several yards without any. support, can move his head and arms with more freedom, and is in all respects much better than hitherto, except that he is very littl¢ improved in respeet of being able to open _ his mouth. It is observable that he sleeps much ; and more particularly after the bath, Dose of opium this even- ing was 120 drops. 16th day.—Much the same. i7th day.—Occasional spasms between his feet and upper part of his thighs, which are yiolent, but of short continu- ance. The ' 2 \» 362 Some Account of a remarkable Cuse of Testanus. ‘The-?: opii has been gradually lowered to 100 drops 5 sit is directed to be diminished five drops, o. n. : 18th dav.—Awoke last night by biting his tongue. The eruption before mentioned is now disappearing ;—-says he is much better. je loth day.—tlas had no spasm during the last ¢4 hours—- P. 75. T. opti gradually brought wow to 80 drops. 20th dav.—Opens his mouth much easier than hitherto— very slight spasms occasionally in.the night. 21st day .—Eruption has now disappe ared.—Generally ¢ cone sidered as out of danger, 2°d day.—Spasms in the left arm and thigh in the course of the preceding night, and also of the tongue and muscles of the jaws. 24th day.—Moves his netk mach more easily than he ~ has ever yet done; and this day, for the first time, he, got up from bed, was dressed, and ate his dinner in that situation, 26th day.—The upper part of the right sterno-mastoid very hard to the touch. The muscles in general soft ;—takes now only 70 drops tinct. opi, It appears that the muscles of the tongue and jaws are almost the only parts that have now for some time been in any considerable degree affected; it appears also that the integuments of that neighbourhood are alone subject to sweating, which has ee from the other parts in propor- tion as the spasms have subsided. In regard to the effect of the cold bath: its regular effect seemsto be that of producing sleep and a great degree of perspiration. 29th day.—Spasm of the tongue more frequent than for some preceding nights. 30th day.—Being now able to open his mouth with con- siderable freedom, complaining only of slight stiffess in the sterno-mastoid muscles, and being able to walk with little inconventence, it was thought proper to relax in Bie mode of treatment. ' Utat. baln. frigid. semel in die. Cap, mist. cinch. vin, rubr. confect. et "he vitr. 5}. 4 die bibat cerevis. fort. tbij. quotid.—a glass of sherry o¢casionally. 31St.— Report of the City and Finshury Dispensaries. 363 31st.—The opiate, which ought to have been 55 drops, was accidentally omitted, however he passed a good night, and this morning walked by himself to the bath, From this time his’ complaints gradually left him : but when the stiffness of the muscles had entirely ceased, the puncture in the foot became painful, and the cicatrix opened, It was troublesome two or three days, and then healed with- out its being known that any extraneous body had been ex- pelled from it. LI. Report of Surgical Cases m the City and Finsbury Dispensaries, for July, August, and September, 1808. - * With the Termination, and Appearances on Dissection, of *the Case of Dropsy in the Ovarium, referred to in p. 86. By Joun Taunton, Esq. Ts July, August, and a earcmben: there were admitted on the books of the City and Finsbury Dispensaries 698 suyical patients. Cured or relieved — 556 Died — — 3 Under cure — 136 ed 698 October 23.—The patient’s pulse was 120, arid thready ; her countenance dejected ; the pain was now extended over the whole abdomen, particularly in the part where the punc- ture was made. Symptoms of inflammation seem to have come on. 24.—The pain increased; the patient had obtained na sleep : she exhibited great anxiety, and the symptoms were attended with diarrhea, and the stomach rejected whatever was administered. RK. Mist. cret. cum tinct. opti; pil. opit cmni nocte. 26.—Pulse 100, and much fuller; stomach not so irritable; the diarrhoea is less, and the pain greatly abated; but the pa- tient experiences great inconvenience from the increased bulk. Repetantur med. et pH. : From 364 Report of the City and Finsbury Dispensaries. From the 29th to the 31st’ she was much better. On the 3ist she sat up in bed, and seemed inclined to have the ge ration performed. The medicines were repeated. Nov. 3.—Pulse 80, and regular. 8. She appeared much better, and seemed to be deenes of having the operation performed. 10.— RBS ten o’clock this morning she was more un €asy, and sat up sometime. On going to bed she slept some hours. Her voice had changed, and her eyes had assumed a different appearance. She continued uneasy until about two o’clock P. M. when she died. 12. The body was examined in presence of Dr. Squire, Dr. Lidderdale, Mr. Grove, Mr. Taylor, and myself. - We were informed by her friends, that she had been mar- ried two years, but never had any children. She was thought to have been pregnant at the commencement of the disease. The tumour was encysted, and reached close to the serobi- culus cordis; the surface was regular, and bore marks of recent inflammation.» The omentum adhered to the upper a. > x and anterior surface. About four quarts of a glary fluid was fonnd external to the tumour at the upper part, with a considerable quantity of purulent matter. “Phe viscera were obscured by the tumoury a a small part of the omentum and colon to which it as attached. The diaphragm was raised'so high. that its convex part reached to the third trae rib, and the superior part of the liver and stomach were opposite to the fourth true rrb, so that a very small! space was left in = cavity of the thorax for the action of the lungs. The tumour consisted of several cysts, from the largest of which about eight quarts of a glary tenacious’ fluid were taken. One of the smaller cysts contained a fluid’as limpid -as water. Others contained a glary and fibrous substance; which could scarcely be pressed from the surrounding parts. ° Large irregular masses were observed, part of them i ina state of suppuration. Over the anterior part of the tumour, and on the right side a thick opaque substance was expanded, which, on dis= ear” proved to be the nterus, but. so changed in its structure N Report of the City -and Finsbury Dispensaries. — 365 structure and figure, that its parts were scarcely distinguish~- able:-this reached from tbe pelvis to the umbilicus, and extended about five inches:in each side of the linea alba; the Fallopian tube, round ligament, and ovarium, on the right side were evident. The uterus was so altered that its cavity could not be traced: the os uteri and posterior part of the vagina W were lost in the diseased Pals and no trace of them existed. On cutting through the anterior aA of the uterus, its sub- stance aed to have degenerated into a diseased mass of small irregular.cysts, terminating in the large suppurated .masses before noticed. The liver adhered to the peritoneum ; ‘its surface bore strong marks of remote inflammation ; the stomach, intestines, peritoneum, and spleen, all had the appearance of inflammation. , In. the operation on the 22d of October (sce the former Report) the instrament had passed into one of the large ir- recular masses which was contained in a cyst full of a thick viscid fibrous substance ; but it should seem, that if the in- strument had been of sufficient iength to have perforated the posterior part of that cyst, and to have entered the large one, several quarts of a viscid fluid would have escaped ; or, if the operation had been performed at the scrobiculus cordis, the fluid external to the sac would have been evacuated, as was suggested at the time. Although the dissection of this-case proves that some re- lief might have been obtained by a trocar and canula eicht inches long, in order to perforate the largest cyst; yet, from the extent of the disease, the operation would in all proba- bility have been succeeded by violent inflammation, which would have proved fatal, as the parts did mot possess elasti- city enough to regain their original situation; neither could. artificial pressure haye supplied the want of support occa- sioned by the evacuation of the fuid, which would have been upwards of three gallons. Joun TauNTON, . Greville street, fable Garden, Surgeon tothe City and Finsbury Dispen- Nov. 28, 1808. * saries, and City Truss Society, Lecturer , on Anatomy, Surgery, Physiology, &e. | Note.—The preparation of the aboye dissection is pre- served in my museum. i ere [- 366 J LII. Proceedings of Eearied Societies. A [5 A Sn ROYAL SOCIETY. fs WNavetnes 30.—Being St. Andrew’s day, the Royal So- ciety held their anniversary meeting at their apartments in Somerset-place, when the president, the right hon. Sir Joseph Banks, bart. K.B., in the name of the Society, pre- sented the gold medal (cailed Sir Godfrey Copley’s) to Wil- ham Henry, M.D., for his various papers communicated to the Suciety, and printed in the Philosophical Transactions. The Society then proceeded to the choice of the council and officers for the en*uing year; when, on examining the ballots, it appeared that the following gentlemen were dlect- ed of the council : Of the old council—The right hon. Sir Joseph Banks, bart. K.B., Sir Charles Blagden, Knt., Henry Cavendish,’ esq., Humphry Davy, esq., John Gillies, L.L.D., nght hon. Charles Greville, William Marsden, esq., Rev. Nevil Maskelyne, D.D., George Earl of Morton, Jolin Rennie, esq., Wm. Hyde Wollaston, M.D. Of the new council—Edward Ash, M.D., Frederick Au- gustus Barnard, esq., John Blackburne, esq., Samuel Good- enough, Lord Bishop of Carlisle, Thomas Earl of Chiches- ter, Henry Hugh Hoare, esq., Sir Richard Colt Hoare, bart., John Lord Selsey, William Sotheby, esq., Sir John Thomas Stanley, bart. And the oficers were—The right hon. Sir woes Banks, bart. K.B., president—William Marsden, esq., treasurer— Wm. Hyde Wollaston, M.D., and Humphry Davy, esq., secretaries. Afterwards the members of the Society dined together, as usual, at the Crown and Anchor Tavern, in the Strand. On delivering the Copleyan medal to Mr. Davy, to be by him transmitted to Dr. Henry of Manchester, the pre- sident, with his usual eloquence, expatiated at considerable length on the propriety of the decision of the cuuncil, and the meritorious and successful researches of Dr. Henry in chemistry, pursuing the same course in which his father so ~haypily Royal Society. S867 happily led the way. The right hon. baronet then took a, view of the various papers furnished to the Society by this philosopher in 1797, 1800, and 1808; and concluded by stating that Dr. Henry, with the most patriotic views, is now devoting g every, 1 moment, not engaged in professional duties, to an imyestigation of muriate of Sore in order*to ascertain the real nature of this useful article, and develop the cause why that of our own manufacture is not so effectual in pre- serving fish, as the salt of warmer climates. The success which has hitherto crowned his labours in this important research, induces him to hope that he will be able to ascer- tain the true cause of the difference between English and foreign salt, and to point out the means of remedying its, defects, and improving this important part of our manufac- tures. The president then congratulated the Society on the rapid progress of science, and the gencral tranquillity in the British dominions, while the nations on the Continent are involved in misery and sanguinary war;—and reverted to the brilliant discoveries of Mr. Davy, which have shed a lustre on the present age. Bee. s..-the nseitla in ae chair.—aA letter from Dr. Flenry to Mr. Davy, on the existence of oxygen in ammo- niacal gas, was read. Dr. H. inserted two pieces of platina wire in straight tubes of glass hermetically sealed, placed them in a glass globe, and made the galvanic fluid pass over the ammonia, when a considerabie portion of oxygen gas {about six per cent) was found to be disengaged, without the possibility of its having been furnished by the materials used in the process. The minute operations and experi- ments performed by Dr. H., to prove the existence of oxy- fen In ammonia, tend to confirm ful ly Mr. Davy’s opinions aa experiments on the base of this substance. . Dec. 15. The reading of. the Bakerian Lecture: by ‘Humphry Davy, Esq., Sec. R.S. “* On some Analytical Researches, concerning the Elements of certain. Bodies ; with some Observations on Chemical Theory,’ commenced.—Ia the Introduction, Mr. Davy observed, that his. objects in these inquiries were to ascertain precisely, the nature of the ele ments of ammonia, and the alkaline substances ; to attempt the 368 Royal Society. the decomposition of sulphur, phosphorus, the boracic, muriatic, and fluoric acids; and to astertain the-nature of the diamond, plumbago, and charcoal. pe The second section was upon ammonia and its elements. —In this, he particularly examined the action of ammonia and potassium ; a process, from which M. M. Gay Lussac and Thenard, had concluded that potassium might be a_ compound of hydrogen and potash. He showed, by a va- riety of experiments, that their conclusions cannot be ad- mitted ; and that in this operation, itis theammonia, and not the potassium, which is decomposed. Mr. Davy described in the course of this investigation, two new substances, one a compound of the oxide of po- tassium and ammonia, and the other a compound of the oxide of potassium and nitrogen. This last inflames spon- taneously by exposure to air, and produces potash and ni- trogen; and it acts violently upon water, and by rs action upon water, generates potash and ammonia. From the general tenour of these experiments, Mr. Davy seemed inclined fo infer that nitrogen in its aériform state, . is not a simple body; but that it contains oxygen, and in its combination with ‘the oxide of potassium Itspossesses me- tallic properties. Dec. 23. The reading of Mr. Davy’s Bakerian Lecture was continued. The third section was concerning the de- composition of sulphur. He detailed a number of elaborate - experiments made upon it by means of Voltaic’ electricity, and by the action OE potassium ; from which he inferred, that it.is a triple compound of oxygen, hydrogen, and a pe- - culiar basis. In this section he detailed an account of a most curious fact, of the brilliant combusticn of potassium in sulphu-- reticd hydrogen gass, proving distinctly that this gas which has long been known to possess acid properties, contains oxygen. | F The fourth section was on the decomposition of phospho- rus, which, like sulphur, enters into ignition, out of the contact of air with potassium, and emits phosphuretted hy- drogen gas when acted on by electricity. : He. Ropeil Society.—Wernerian Natural History Society. 369° He ‘considered phosphorus ‘as a compound of a small ’ quantity of oxygen and hydrogen, with a peculiar basis ; and both sulphur and phosphortis, as analogous to the resi- nous and oily bodies, except that the base of these last bo- dies is carbon. 3 i In the fifth section; plumbago; charcoal, and the dimond were considered as to their affections by the new methods. of analysis. Plumbago, Mr. Davy considers as a combi- nation of the pure carbonaceous element and iron. Char-: coal, as a compound of the carbonaceous element and a lit= tle hydrogen’: and the diamond, as composed of the same element with a minute quantity of oxygen; In the sixth section, the decomposition and composition of the boracic acid are detailed. This acid is decomposed both _ by voltaic electricity and the action of potassium; and its base, by being combined with oxygen, reproduces boracic acid,—thus ene former analogies. The reading of the remainder. of the lecture was Se feat ed till the next meeting of the Society in January. ‘ s ‘By attending to the second reading, of Mr. Children’s. paper on EVAR batteries, we find that we reported it in- correctly in our Jast number (p. 185 of this volume). Mr. Children stated that batterics with large plates should be used for operations on perfect conductors, and small plates, in great numbers, for operations on imperfect conductors. This principle is of great importance in the construction of tiie machine: = WERNERIAN NATURAL HISTORY SOCIETY, At the meeting of this Society, 10th December, the se- eretary read 2 communication from the Rev. John. Fleming of Bressay, describing a Narwhal or Sea Unicorn, of the sort denominated Ee WNarwal muicrocephale, by La Cepéde,. which had been lately cast ashore alive at Weisdale Sound fa Mainland, the largest of the Zetland islands. . The de-, scription was acconipanied with a correct drawing of the ani~’ mal, which is to be engraved. At the same meeting, Dr. Ogilby, of Dublin, Ha: & Vol. 32. No. 127. Dec. 1808. Aa paper 370 Wernerian Natural History Societsj.— Intelligence. paper on the Transition Greenstone of Fassnet in East Lo- thian, which, besides much valuable mineralogical infor- Imation, contained a satisfactory answer to the query pro- posed some time ago by Professor Jameson, i in regard to the geognostic relations of the rocks of this traet-of country. The descriptions of the individual/ rocks, and their general and particular 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 following gentlemen have been elected office- bearers of this Society for 1809: President : Robert Jameson, esq., Pr. Nat. Hist. Ed. Vice-presidents: Dr. Wright, Dr. Macknight, Dr. Bars clay, and Dr. Thomson. Of the Council : Gen. Dirom, Col. Fullerton, C. S.Men- teith, esq., Dr. Home, Dr. Yule, James bist, esq., C. Anderson, esq., and C. Stewart, esq. Treasurer: Patrick Walker, esq. Secretary : Patrick Neill, esq. LiL, Intelligence and Miscellaneous Articles. MR. DAVY’S THEORY. £6 are TILLOCH,—SIR, Proressor Davy this day, in his lecture on ches mical affinity at the Royal Institution, brought forwards (not indeed for the first time) his theory, that chemical af- finity was the effect of opposite states of electricity. This theory he proposed with all that diffidence and _ hesitation which are ever inseparable from the man of true science in such matters. Having stated that bodies which are possess- ed of chemical affinity are also naturally in opposite states of electricity, and that this affinity is dependant upon their state of electricity, he proceeded to illustrate the doctrine in various ways, giving examples of this dependence, and showing that bodies which have their states of electricity altered ~ Mr. Davy’s Theory. 371 altered by means of the galvanic apparatus, have at the same time their chemical affinities also altered. Thus a body which is naturally positive, but only in alow degree, will, have a very weak attraction for oxygen, which is naturally negative; but exalt this naturally low positive state by means of the apparatus, and its attraction for oxygen shall be strong in proportion :—for example, silver, which 1s na- turally positive in a low degree, is incapable of acting upon water ; but if you exalt this natural state of electricity, by means of the galvanic apparatus, it will become capable of extracting the oxygen from it. ‘¢ As a further illustration of the theory he stated, that if -- the states of electricity of bodies which naturally were pos- sessed of strong chemical affinity were by means of the ap- paratus entirely reversed, the consequence would be a dis- union and destruction of the compound which they formed in consequence of their natural affinities. *¢ To prove this, the following experiment was performed : —Moistened sulphate of potash was placed in the galvanic circle, and presently it was decomposed ; potash appearing at the negative and sulphuric acid at the positive side. This’. effect is produced, says Mr. Davy, by the action of the gal-— vanic apparatus inducing a state of electricity in the sul- phuric acid, the reverse of that which is natural to it, and the same in the potash ; and in consequence these two sub- stances, instead of combining, actually repel each other, and are found on opposite sides of the vessel in which they were placed in combinaticn, the acid at the positive side and the potash at the negative. ; « Mr, Davy oe to rely much upon this experiment ; but his explanation of it, if I did not much misunderstand him, seems to militate against the doctrine he brought it forward to support ; for He explained it upon this principle : : that the natural electricities of two bodics which were in chemical union, being by means of the galvanic apparatus- reversed, they would, as a natural consequence, repel each other, and thus be found in a separate state 10 the vessel in which the compound was placed. of This experiment, as above explained, daes not seem to Aaa afford 372) | Mr. Davy’s Theory. afford any support to the theory, nor does it appear to me to offer a satisfactory explanation ; for in the first place, the sul- phuric acid and the potash being placed in the galvanie circle in a state of chemical union, it isnot shown, nor is it easy! to conceive, how a state of electricity contrary to the natural. one should be induced in the acidsand potash, rather than’ that their natural electricities should-beraised and their union” rendered stronger; and secondly, supposing the change in the electricities to have taken place, then the acid, having become positive, ought, according to the true principles of the theory, to unite with the potash which is, become nega- tive; and this for precisely the same reason that they united when the acid was negative and the potash positive. << Tam inclined to think, however, that the true explanation of the’ above-mentioned experiment is the following: The positive and negative points of the battery act upon: the _ moistened sulphate of potash precisely in the: same way that any neutral salt wouldact, which might have the power of ee it, the basis corresponding to the positive side of the apparatus, and the acid to the negative. < $¢]tis thus, I conceive, that the He of the sulphate of potash in the experiment above mentioned is _ effected by the galvanic apparatus ; for thenegative side, being in a higher state of electricity than the sulphuric acid, will attract the potash ; and the positive side, being in a higher state than the potash, will attract the sulphuric acid. — *© Hence the reason that the sulphuric acid and the pot- ash refuse to unite, though stated to be in opposite states of electricity, and not because their natural! states have been changed; for the last reason is in direct contradiction to.other facts w Lectures, 373, facts brought forward to illustrate the theory, which show that sp Neats having its natural state of electricity reversed, will become Sse of attracting another which “fences it repelled. <¢ If, by inserting the above observations in your Maga-_ zine, you should cause them to be either confuted or con- firmed, you will much oblige your humble servant, Dec. 24, 1808. «© AUDITOR, ? LECTURES. Mr. Sowerby’s Lecture on Chromalometry —On the 12th and 19th of December, Mr. Sowerby, author of British Mineralogy, &c., delivered his long promised Lecture on Chromatometry, at his house in Mead- Place, near the Asy- lom. This Lecture, the object of which is to point cut a new. and very ingenious mode of ascertaining the arrangement, mixture, and* measure of prismatic tints, and to show their correspondence with material colours, was accom- anied by an cxhibition, in which the prismatic tints were roduced, as from the sun, ‘moon, and stars, the sun as seen fom the different planets, and a productor, 60 feet long, 1SU intinite series: also the material and prismatic tints weit 2 mixtures in union, with the effect as from can- dies, and flambeaus, and a sort of prismatic illumination, with different lustres, from metals, &c: The whole was . elucidated with apparatus of a new and original kind, which promises to assist the philosopher in very much extending our knowledge on this subject.—Mr. Sowerby continues to sepeat the Lecture every Monday, and has announced a work illustrative of his discoveries. Theatre of Anatomy. —Mr. Taunton will commence his Spring Course of Lectures on Anatomy, Physiology, Pa- thology, and Surgery, on Saturday the 21st of January, 1809, at Eight o’Clock in the Evening. In the Course of these Lectures Mr. Taunton will take a view of the Structure and Cconomy of the Human Body, and describe the Causes, — Symptoms, Natare, and Treatment of Surgical Diseases, with the Mode of performing Operations. The Course will be calculated to afford Anatomical and Physiological Instr uction, not only to the Medical Student, but to the Artist, or pri- vate Gentleman. Particulars may be had on Application to Mr. Taunton, Greville-Street, Hatton-Garden. London 374 ‘ Lectures:—Patents. is Bee Hospital. —Dr. Buxton’s fadenes on the . Theory, and Practice of Medicine, and on Materia Medica, will be commenced about thé 20th of January, 1809. For parti-, culars apply to Mr. Price, apothecary, at’ the Hospital, or to Dr. Buxton, Fenchurch-Street.- Tt is with extreme regret that we announce the death of Dr. Beddoes. . He git: at Hotwells, Bristol, on Saturday the 24th of December. LIST OF PATENTS FOR NEW INVENTIONS. To Edward Thomason, of Birmingham, in the county of Warwick, manufacturer, for his various improvements in the construction of umbrellas and parasols. Oct. 8,- 1808. To Richard Trevithick, of Rotherhithe, in the county of . Surrey, engineer, and Robert Dickinson, of Great Queen- Street, in the county of Middlesex, esq., for their new me- thod or way of stowing cargoes of ships and other vessels, by means of packages, for containing goods and products of certain descriptions, destined for conveyances by sea, not hitherto employed, by which means expenses of stowage room will be saved, and the contents be rendered more se- cure from damage.” October 31. To Henry Van Wart, of Liverpool, in the county pala- tine of Lancaster, merchant, that, in consequence of a com-~ munication made to him by Isaiah Jennings, a citizen of the United States of America, he is in possession of a method of making a machine for manufacturing thimbles for the sails of ships and vessels, and for all sorts of rigging and other purposes. October 31. To Joseph Anthony Berrollas, of Denmark- rei, in the parish of Saint Giles in-the Fields, in the county of Mid- dlesex, waich-maker, for his new-invented method of making infallible repeating watches. October 31. To Zachariah Barratt, of Croydon, in the county of Sur- rey, gent., for his new invented machine for washing: linen and coiton clothes, and other similar things, to which may be affixed or omitted at pleasure a contrivance for pressing the water from them, now done by w ringing. Oct. 31, “METEORO- Days of the 2 2 Month. E 2 waa Nov. 27) 51° 47° - 28! 34 | 40 29; 34 | 39 30] 46 | 47 Dec. 1) 44 1 48 a ML A a 3| 43 | 48 4|-45 | 46 5| 36 | 48 6) 48 | 52 7| 35 | 48 8| 36 | 43 9} 41 | 43 10} 35 | 40 W113 37 12) 37 | 43 13| 40 | 37 14| 35 | 39 15| 36 | 38 16| 34 | 36 Pas IO i8 19} 30 | 30 20) 25 | 29 Z1} 20 |. 30 22) 31 | 31 93) 28.\. 29 24} 32 | 32 26 st 22 ir Gk cars on Meteorology. METEOROLOGICAL TABLE, . By Mr. Carey, oF THE STRAND, For December 1808. Thermometer. Night. 11 0 Clock, Se) aa 3° 09 nS re om o'r 44 to Gr a om oo Co = 30 29 25 30 31 28 28 30 31 Height of | the Barom. Inches. 29°45 "82 °68 “28 “50 "25 "41 30°12 “19 29°81 789 "98 92 30°10 “25 "26 "32 *93 “ll “05 99°48 ye) Ns ness by Leslie’s Hygrometer. Degreesof Dr co) 10 Weather. a Stormy Fair Rain Fair {Fair Fair Fair Fair Cloudy Clady Fair Cloudy Fair. Foggy Fogey Fogey Foggy Cloudy Fair Fair Rain & snow, with h. wind. At 8 o’cl. in the even* the therm. stood at 22 degrees Fair Cloudy Bare Cloudy Snow Cloudy Cloudy Cloudy Cloudy WN.B. The Barometer’s height is taken at one o’clock. eS The binder is desited to suppress a Title-page given with No.CKXYV. " and to substitute the one ii the present number. c +396 a iNDEX to VOL. XXXII: RUBE. TS Accums arialyeis of Chelten- ham waters, i 57 Acids. Thomson on oxalic, 39; Davy’s experiments on, 201; carbonic decomposed by po- ~tassium, 221; boracic compo- sition of, 369 Alburnum. Alkaline Earths. On opinions respecting, 15,62; decompo- sition of, 152, 193; on the me- tals of, 199 Alkalis. theory of, composition and production, 7 ; basis of potash, x0; amalgamates with mercu- ry, 115; basisof soda, 101; constituent parts of potash and soda, 105 ; relations of, 109;° nature of ammonia, 146, 367; decomposition of potash by iron, 89, 219, 276 Allen on respiration, 242 “lumine. On decomposin 203, 207 Ammonia. Decomposition of, 146, 367; amalgam from, 269, 215 Ammonium: Production of, 209, 216 Hiaiiies of Cheltenham waters, §75 of potash and soda, 1, 101; . of pit- coal, 140, 309; - e monia, 146; of barytes, 198; of strontites, 202; oftlime, 198; magnesia, 152, 202; com- pound inflammable gases, 277 Arcbitecture. Remarks on, . 97 Ardea Aiqu'noctialis, 328 Astronomy, 94, Ig! Atmospheric air. pys's experiments on respiring, 24% Bark. Knight on 134 Barytes. On decomposing, 151; metal of, 198, 201 Beaver. On breeding the, 77 Knight on, 134,299 - Decomposition of, 1}. f, 1525, _ Chromatometry. Alfen and Pe- Bell's invention for. aie ships wrecked mariners, 204 Berzelius’s decomposition of ba-. rytes and lime, 198; of am- monia, - 209 Birds newly discovered in Bri- tain, 328 Bond’s machine fobueealene iin 69; on rabbits, &c. Books, news 88, 181, 3 Boracie acid. Composition of, 369 Brande on calculi, 167, 234 British Birds. On, 315 Calculi urinary. Differences in, 167, 234; Home on, 239 Carbon. Mushet on, 309 Carbonic acid decomposed by po- tassium, ; 227 Carey’s meteorological tables 96, 1925 375 : Carnot on machines, — 124 Charcoal. Composition of, 369 Chelienbam waters. Analyses of, Children on galvanic batteries, 185, 369 On, 375, ft Cleali’s machine for beating ont hemp, 06 Coals. On distillation of, 1315 5 ’ analyses of, 140, SOR gas from, 286 Collier's ship stove, 11g Combustib'es, attracted by nega- tive electricity, — 153. Commerce. Grahamon, 267 Copper. Desulphuration of, 84 Darwiniana, 30, 158, 329 Davy’s Bakerian lecture on de- - composition of alka’is, I, 1015 : 146; on ‘the decomposition of\ the earths, 193; and other sub- stances, 368; on new “= of, aces (£.) description of - INDEX patatus for decomposing pot- ash by iron, 276 Desulphuration of metals. On, 78 Dianord. Pompe on, 369 Diseases. Treatraent of, 329, 357 Dispensary Reports, "86, 363 Earths, alkaline. On opinions Tespecting, 15, 62, 193; on decomposition of, 152, 193; on the metals of, 199 Electricity. Chemical changes effected by, 1, 101, 1463 posi- tive, attracts oxygen, 1535 7¢- gaiive, attracts combustibles, 5533 omactionof, 185,370 Encaustic painting. Practice of, 120 Falco cinerareus, 321 Falco cyancus and pygargus. On the 315; Hyemals, 320 Flax. Machine for beating seeds, 66 Frigorific mixtures. Walker's, 177 Galena. Roasting of, 78 - Galcvanism. De Luc on action of, 185; batteries, Children on 185, 369 Gases, compound inflammable. On analyses of, 277 Gas Lights. Murdoch, on 113; Henry on, 286 Gay and Thenard’s process for de- composing potash, &g, 219; experiments on potassium and ammonia, 219 Glareola austriaca, 329 Glass. Decomposed by potassi- “a UE 17, 208 Cluctae: On decomposing, 152, 203, 20 Graham on commerce, 257 Grates. Experiments on rearin yp Pp 8 , eo Groomb; idge’s Ephemeris of Ves- ta, 94 Guanaco or cane sheep. On, 77 Gueneveau on desulphuration of metals, 78 $77 Hachette’s description of the French apparatus for decom- posing potash, 89 Hemp machine for beating seed 66; culture of, 69; machine » for ‘breaking, 13 Hen Harrier and Ringtail the same species, 316 Henry on analyses of compound inffammable gases. > la, Home on urinary calculi, 239 Hooker (Mrs. Jon éncaustic paint~ in %; 120 Hydruphobia. Cure of, 273 Incombustible man, 47, 159 Knight on alburnum and bark, 134, 2993 on the variegation of plants, 306 Learned Societies, 366 Lectures, 191, 373 Le Caan’s improved tram plates, 130 Light. Experiments on produc- - tion of, 277 Lime. On decomposition of, 152; metal of, 198, 202 Linnean Society, 182 Machines. Carnot on, ~* 124 Magnesia. On decomposing, 1525 metal of, 202 Magnet. Tron taken from the _ eye by a, t54 Medicine, BCs 273 329 Mercury. Amalgams of, with potassium, 196; with lime metal and barytes metal, 1983 with ammonia, 209; desul- phuration of, 84 Metallic ox.des revived by potas- sium, 17,196 Metals, naw, 19, 201, 202, 209 Meteorology, 95, 995 192, 375 Mineral waters. Analyses of, 57 Montagu on British birds, 315 Murdoch on gas lights, £13 Musbet on coles and cokes, 309 318 Qii:, Decomposed by potassium . a7 Ol-fiant gas. Experiments on,286 Ornithology, 316 Oxalic acid.. On ~ Oxygen, attracted electricity; by positive 153 Rivas oS Patents, Vie ae Gina Penduli:m. Ward's compensation silk Pepys on respiration, 242 Phosphorus. Composition of, 369 Pigram’s extraction of iron from the eye by a magnet, 154 Pine T.m!er, abundant in Cana- da, 78 Pit-coal. Tistillation of, 115, 2915 analyses of, 140, 309 ; as from, 286 Planis. On the variegation of, 306 Plumbago. Composition of, 369 Pontin's decomposition of barytes and lime, 198; of ammonia, 209 Potash, Decomposition of, 1 ; basis of, 10 ; constituent parts of, 105; apparatus for decom- posing by iron, 89, 219, 276 Potassium. Davy on 1, tor, 146 Proust on Prussiates 339 Prussiates. History of, 336 Publications, New, 88, 181 Rabbits. , On breeding, 74 Respiration. Allen and Pepys ex- periments on, 242 Ringtail and Hen Harrier the same Species, 319 Royal Inst.tu ion, 191 Royal Society, 181, 306 Scolopax noveboracensis, 329 Seeds. On structure of, 223 Sementini on the incombustible man. 47 Ship Stove. Improved, 119 Sodaium. Davy on, 1, 101, 146 INDEX. Shiswreck. Invention for saving lives from, + gh ee Silex. On decomposition of, 152 ‘ 203, 206 Silvia Darifordiensis, 323 Smiib on the structure of seeds gee Soda. Decompositition of, 1; basis of, 101; ingredients of, Fe i 105 Strontites. On decomposing, 151; metal of, © to 4 202 Sulphate of poiath, decomposition of, 2) OSE Ta Sulphur. Composition of, 369 Surgical cases, 86, 154, 357s 393 Tantalus viridis, 39 Taunton on Tetanus, 357 Taunton’s Dispensary Reports, 86, 363 Tetanus. Case of, 257 Thenard’s process for decompos- ing potash, 89, 219; experi- ments on potassium and am- monia, ye2 rp Thomson on oxalic acid; 39 Tram plates for rail.roads “130 ‘ 372 D4. Experiments on rearing, Urine. Experiments on, Vesta. -Evhemeris of, Vines. ‘ E 397 Viper. Remedy for bite of, 273 Walker's frigorifie mixtures, 177 Ward's compensation pendulum, 22 Water. On supplying cities with i pape 9% Wernerian Natural H story Socie- ty, ie 86, BO Oui Young's Croonian lecture, 185 Zircone. On ‘deco nposing 203, cated a 207 END OF THE THIRTY-SECOND VOLUME. Printed by Richard Taylor and Co. Shoe Lane. ‘SIs Pee. azo ——_ os MOT. 4; 1969. | Phil, Mag. Vol, XXX. 77.1. ond te Vb : rter, Sc a?) Ase f? M 9 y He G ms adhe Z 2 > OC ‘ Mr Cont ‘ bachone Tao ; Phil MagVol. XXXIV.PLU. LOR On === Sika! HWard, tau” Son ff a say i. shins ere. Phil. 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