SS S ANNALS OF PHILOSOPHY : OR, MAGAZINE OF CHEMISTRY, MINERALOGY, MECHANICS, NATURAL HISTORY, AGRICULTURE, AND THE ARTS. BY THOMAS THOMSON, M.D. F.R.S. L. & E. F.L.S. REGIUS PROFESSOR OF CHEMISTRY IN THE UNIVERSITY OF GLASGOW, MEMBER OF THE GEOLOGICAL SOCIETY, OF THE WERNERIAN SOCIETY, AND OF THE IMPERIAL MEDICO-CHIRURGICAL ACADEMY OF PETERSRURGH. VOL. XV. JANUARY TO JUNE, 1820. Dondon : Printed by C. Baldwin, New Bridge-street ; OR BALDWIN, CRADOCK, AND JOY, 47, PATERNOSTER-ROW, ~~ 1820. PRIS eq weea-. ; th MAYA Seve Y Cray ct te TABLE OF CONTENTS. NUMBER LXXXV.—JANUARY, 1820. Page On the Solubility of the Salts in Water. By M. Gay-Lussac. (With a Brae Soa, A a co ok Ue Oe Saisiate = ysl es sim. cibte a sae { Further Observations on the Use of Gauze Veils as Preservatives from Con- poemeeer ey Mir: )Biartletgr. 3: eee. any a es og a 12 Researches on a new Mineral Body found in the Sulphur extracted from Pyrites at Fahlun. By J. Berzelius (concluded). ........ sake x Toni 16 Answer to Mr. Venables’s Queries respecting Cyder-making ....... tones 27 On the Cornea of the Eye. By Mr. Booth.............0.0c0ceeceeues « 30 Experiments on the Gas from Coal. By Dr. Henry, F.R.S. (concluded.) 32 Analytical and Critical Account of the Philosophical Transactions of the Royal Society of London, for VOMOMPari le. 6% cats. oa cite mecha Bare eas 40 Proceedings of the Royal Society, Nov. 25, 30, Dec. 9, 16, and 23... 55 Linnean Society, Nov. 2, 16, Dec. 7, and2h .,....4. 56 Geological Society, June 18, Nov. 5, and19....... 56 Royal Academy of Sciences, ..........00.06e0cecs05 58 ECS: ah ea SERIE... ny RI a ri im I it 65 Remarkable Difference between the Celestial and Terrestrial Arc of the RP TAID & oh PSs s T= dhs LE Pee th «8 wre Bopie adieteeril rors: ahivle Jars eysbrsie 66 Position of different Places on the North Coast of ATTICA) et sc ae eae: 67 Position of different Places in Sicily and the Neighbourhood............ 68 Positions of different Placeson the North Coast of Africa. .............. 68 Position of various Places in the Mediterranean..........2..0cee0...-.. 3 69 Position of La Valetta, in Malta...................6.-..%...4 dubaavg aM 69 Geographical Positions of several Places in F rance, Switzerland, and Ger- BMRRAN ord)-\ 0:0) 4:0)0'vieis tn dfitosetcieta ove vendleeaeh ne oc cee eT be ceseceseesee 70 Latitude of the Observatory at Manheim. ..............-06. Bp OOO SHE BEE 70 Height of the Passage over the Splugen........ qe ois ft ate aaa Hopes 776 Further Observations on the Double Rainbow seen at Paisley. By Mr. ENDER e e n o e eaeT ey SOBA. 71 On Rain-Gauges. By Mr. Holt. ........ pastvcsegessmuay te eae terete 71 Further Remarks on propelling Vessels by Windmill Sails. By Mr. Bart- SOCAL RASS AS ERAREREY Ren aP OM ares gL) ie Tea) 73 Galvanic Experiment ............... Be elan. Oh 107 SAEs Boe H A Rise! Seog Singular Substance found in a Coal Tar Apparatus. By Mr. Garden.... 74 Deathrot Dr." Ratherford\) 22 rr). eo ee, 75 Col. Beaufoy’s Astronomical, _Magnetical, and Meteorological Observa- ons “foe Noventoerss. 8) 8) 20! poi. ey Wer 76 Mr. Howard’s Meteorological Journal for November.................-. 79 1v CONTENTS. NUMBER LXXXVI.—FEBRUARY. Page On Arsenic. By Thomas Thomson, M.D. F.R.S. .......-00sseeceeeee 81 Experiments to determine the exact Composition of different inorganic Gapdles.) by Professor Berzelius... 0... 0¢206 tapas ue on oes ene 89 Demonstration of Dr. Taylor’s Theorem. By Mr. Adams...........+. oT) On Urinary and other Morbid Concretions. By W. Henry, M.D. F.R.S. 107 Sasalpauric Ether. By J. Dalton .. .... 6... os scnoukeesss «+4 sme 117 Calculations of the Annular Eclipse. By Col. Beaufoy, F.R.S..... ... 183 Analytical and Critical Account of the Memoirs of the Literary and Philo- sophical Society of Manchester, Second Series, Vol. III.......:...... 136 Proceedings of the Royal Society, Jan. 13, and 20.............00eseee 142 - Geological Society of Cornwall .............. 143 Analysis ofa Specimen of Blende: .. 205... 0.050 Gb ee ws cote rvs smensnese 146 Chemical Analysis of Egerant”. .os.s+ + se oweitucstels cts > <7 a seater 146 New NICK El Ore sachs Co cee te TE Ee ainice:. c/a te eater teats 147 BOM ONT OL OURS te ste cele ean Me eseniet cles turers les ete tenets Seve mane 148 Moe eae Sater ace Shite se aim suet mereys laters s vtah eis are oie kestets cketes ares erate 148 Declination of the Needle at Lyons.......... 2.25.2. eccceeeceecseceees 149 ~ Bosittoniof- Ruccalt. 2. .seccs-s see ee nese SHERRI cHADotrarac bite. 149 Position of Montpellier ........2.-eecee ee ee eects cece cess cs ee eeeeeees 149 Determination of some Places on the Coast of Sicily.......... ......- .. 149 Occultations of Stars behind the Moon, observed at the Observatory of the Royal Academy of Turin between 1812 and 1817. .....-+-...0.. 05 150 Position of Places on the Coast of the Adriatic Sea .............+-.004e 150 [PAGE OI | Free ore ete die ici Ja ocioce Sc idatia orig acsicbcrgoG scr 152 Population of the Calton in Nov. 1819 ........0.-+eeseeeeeeeeeeren eens 152 Meteorological Journal made at Cork. By T. Holt, Esq. (With a Plate.) 154 New Rockets: ..22.cccsscecusccessecceoe seve cscwecce Je vaviins ancl 155 Pink Sediment of Urine. . .. i... .. cc ceeccec ces cece re ecces seeecees 155 Col. Beaufoy’s Magnetical and Meteorological Observations for December 156 Mr. Howard’s Meteorological Journal for December. ......-+++s-.00e . 159 ———— NUMBER LXXXVII.—MARCH. Biographical Account of Stephen Hales, D.D. F.R.S. ....-. ++ ++ eeeeeees 161 Description of a Barometer for measuring Heights. By James Allan... 171 Results of a Meteorological Register kept at New Malton, in Yorkshire, in 1819. By Mr. JamesStockton ........-0+seeee eee eres cee eee anee 174 On the Going of a Clock with a Wooden Pendulum. By Col. Beaufoy.. 176 Extracts from the Persian Work called ‘‘’The Book of Precious Stones,” by Mohammed Ben Manssur ......--.++¢e+reeeeserertee seers ees 178 Description of an Apparatus for the Analysis of organized Substances. By W. Prout, M:D.F-R:S. (With a Plate:). ......-2-000s2-- een daees -- 190 Analytical and Critical Account of the Memoirs of the*Literary and Phi- losophical Society of Manchester, Vol. III. (concluded.) ........+4. -» 192 Proceedings of the Geological Society, Dec. 3, 17, and Jan.) 7a e210) Royal Academy of Sciences. .....-se5seccueeeene. 215 CONTENTS, ey: Page Pravoxide and Deutoxide of Azote 7. 8. i She hos onen 224, perPUONINS FAPIC cs he emer ACN oe tec. aera aren a 22T Meteorological Register kept at wmiauns’ Castle: =: .. saceeene, eee 231 An Account of the State of the Barometer, Thermometer, and Wind, dur- ing the late Hurricane at the Island of St. Thomas’s, in the West Indies. Communicated by Col. Beaufoy, F.R.S. 0.2.2.0... 0... ccceccecaeee ee 232 Method of determining the Specific Gravity of Gases. .....22....0se0ee: 232 Pamibingtions Of rmeic Acid... .: .../ see eee ee 233 Geographical Position of Modena. ............0.0.0cceeeeeceueeees core 234 | RUD ae aa es le gi aioe ib Maer ali test Tai ha IRR RR 235 On fattening Pigs. By Mr. J. Murray.............. eoralelairietcte rere isiseate 235 Varnish for Wood. By Mr. J. Murray.........20. 0. eeceeeeues o8gHb De 235 Col. Beaufoy’s Magnetical and Meteorological Observations for January. 236 Mr. Howard's Meteorological Journal for January ............... seeces 239 ~ +4 WOT $5] a SS HR a a HY a a PS § ] 8 9 LLALL. ©. Engraved for D? Thomson's tale. for Baldwin, Gadock & doy. Paternoster Row, Jan? 1.1820. | | { 1820.) Solubility of the Salts in Water. 9 necessity, in order to compare its solubility with that of other salts, increase each number of solubility by the same number multiplied into the ratio of 22:65 to 131-1, and diminish by as much the quantity of water. On making this correction, the preceding results will be changed into the following : Temperature. Salt dissolved in 100 water, 0S RPA: © SOrnee 43°50 22 e Widen tins . 55°63 og ey eer 65°51 TODAS i arin vis ace case cevs 27°89 These results are represented by a curve deviating very little from a straight line. They are represented on the plate. Solubility of Chloride of Sodium. Temperature, Salt dissolved in 100 water. WO i csidintnie int.» « Miracola . 30°81 PO) «cc's wiao, atsinyhertio nesses GO'O0 eee ew ee ss) pia 37°14 MUI Ags ts) sarin: wiitd vioh Sx 0° 0 40°38 ~The line of solubility of this chloride is not a straight line ; for the equation of a line passing by the two extreme ordinates, 35°81 and 40:38, is y = 0:04768 x° + 35:15, and the solubility calculated from this equation for the temperature 59-93° is 38-01 instead of 37:14, which experiment gives. At the temperature of 0°, I found a solubility a little greater than at 13-89°, and I intend to make new experiments to investigate this anomaly. Solubility of Sulphate of Potash. Temperature, Salt dissolved in 100 water. LA ps i eat s abiietat ore) ats 10°57 BION oss esis sus Ris fatst ane iaie. 16-91 63°90 . ae 19-29 BOE tres asain cease ec s> 0s & 26°33 The line of solubility is a straight line whose equation is y = 01741 a° + 8:36 Solubility of Sulphate of Magnesia. Temperature. Salt dissolved in 100 water. MDOP didi se 6 Sedge wibig) daiebereO oy ee raved ale Soaere 45°05 RP ict S > ope al wi italanest ale 49°18 ERLANG alo aie Ah wep! Gey iin 0 fae lo 56°75 DO ete cB ate tele weve ace iia tan The line of solubility is a straight line whose equation is y = 0°47816 x° + 25°76 The sulphate of magnesia is here supposed anhydrous ; but as 10 . M. Gay-Lussac on the Pan. it crystallizes retaining seven portions of water, 79-3, for one roportion of salt, 74-6, each number which expresses the solu- Laity, must be increased by this number multiplied by the ratio of 79-3 to 74:6, and the corresponding quantity of water dimi- nished as much. We shall thus have for the solubility of crystal- lized sulphate of magnesia the following results : Temperature. i OS tis os pigtgta's dtote 103-69 30°86 pans Ser eer 178-34 eee ce Lo, alg vip oe 212°61 BBO si stein: sre Suen (al. selatea 29513 NOES cree encore Gees eats | 644-44 These results are no longer proportional to the temperatures ; they augment in a much greater ratio. Solubility of Sulphate of Soda. Salt soluble in 100 water. Temperature, Anhydrous. Crystallized, OPO GRRE, sieves. tet oO: + sh 5* hide 12:17 NO Nd oy hori ee FORD cate iar 26°38 AS BO sai snereuen aie ak LEA. ih cs aan Sue So Laie) a aa eae LOE. alanis SCS 48-28 ASD 0) 7 a dees =o i tl Sg eee 99-48 2 34°30.) nc veraieaile 161-53 aT LaDy a igs % oesay ibis AD OD, -cinsdnataale 215:77 Eanes can ry [3 eee Pe eo 270-22 Fe Ledeen bin o tycintreis 5) OY ee ea 322712 BOOMs wicks. sci sve, sts SUS cs...cie cae 312-1] AOS RS Noes ABS) an adhd 291-44 BOA a anor 3,8 aiden Cp >) SaaS, 2S 27691 SOA Sai esi ai are ADS? s OOs denencOe- On EL RA a 7 a GONG eee tice ats. < ses 5 1) RE Pe Oe icine oh xa coe 4206 occa ee LOSS 2 Sn a eee 42°68 “oo ieee We see by these resuits that the solubility of sulphate of soda follows a very singular law. After having increased rapidly to about the temperature of 33°, where it is at its maximum, it diminishes to 103°17°, and at that point it is nearly the same as at 30°5°. The sulphate of soda presents the second example of a body whose solubility diminishes as the temperature augments ; for Mr. Dalton has already observed the same property in lime. In the plate, the line of solubility of anhydrous sulphate of soda is traced. It consists of two branches convex towards the axis of the abscissas, and having a point of contrary flexure corre- sponding nearly to the temperature of 33°. It was not possible to represent more than a small portion of the line of solubility of crystallized sulphate, on account of the great extent of the ordi- nates; besides, this line could not be of use beyond 50°, because 1820.] Solubility of the Salts in Water. 1) the sulphate of soda does not then retain a quantity of water as considerable as in low temperatures. Solubility of Mitrate of Berytes. Temperature, Salt dissolved in 100 water. OOO. as tate tie iiew lapnbe. eee 5:00 PALO £5 sin? it as deanetalese tes 8-18 pg 6 a Oto it 8°54 TE eS Gas cen eee folate 13°67 SDE is) 0 wine, Oa eras 17-07 5S ED GF Ds arta tela a 17:97 Rael Dh ce Se ee Sietats oniete leks 25°01 OOHZE Seta. Weed: RS ae 29°57 LOMK65%. 0.4 ph 25s, Me 35°18 Solubility of Nitre. Temperature, Salt dissolved in 100 water. WOO iss wares se. 13°32 bles niiveaeeke, 16°72 Ashe G ey oh toag v4 in aaratthele/ ots letatiite 22:23 Ai le Deke ek ke Pe 29°31 ADA ita tcnctahalise\a, aid « tare)a vai 38°40 RED yt aia DP aikiar ci tei beeen . 54:82 Gil Oomid bea desea .- 74:66 BA De se wea sitatale Kogerornes 97:05 GiAoitaawpanae sted des oe 125-42 OD is aibhuc tes steelm 64's 169°27 DE-GBi ges EA eaeiie w+. 23645 Solubility of Chlorate of Potash. Temperature, DQ Sabed a beiaars ssrecoseparncatonbig 3°3 WS-Bps Pinter b As elem Hrs 5:60 Lah as ter Od oe hagd seo 6:03 BAAD iy ybidsictsi fists b Rept ew. 8:44 BA Was arr aipedtspee ens < 12°05 AOD ia shee nits Gla Frere 2% [ere 18°96 168 oat ch cbs sie joes 35°40 AOA ABs rds siete Be 4 jai hisiedep OU; 24 The lines of solubility of these three salts are represented in the plate. They show at once to the eye that the solubility of each salt, especially nitre, increases at a great rate. It would have been possible to have represented them by algebraic for- mulas, but their graphical lines have the advantage of giving immediately, and without calculation, and with almost as great precision, the solubility for all temperatures between which the experiments were made. I intend to give in a second paper the solubility of a greater number of salts, and to present them under the form of tables for every five degrees of temperature at least. 12 Mr. Bartlett’s further Observations on the , (Jan. The results which I have obtained, though not numerous, are sufficient to show that if we cannot hope to reduce the solubility of the salts to general principles, it deserves at least a particular attention, expressly in consequence of the anomalies which it exhibits. I abstain at present from drawing any consequence ; I shall wait till I obtain the assistance of new experiments. Artic.e II. Further Observations on the Use of Gauze Veils as Preservatives from Contagion. y Mr. Bartlett. (To Dr. Thomson.) SIR, Buckingham, Oct. 11, 1819. Wuen I suggested, through the medium of your Annals, the use of gauze veils as preservatives from contagion, I was not aware that M. Rigaud de l’Isle had, in a memoir “ On the Physical Properties of Bad or Unwholesome Air,” the aria cattiva of the Italians, read at a meeting of the Royal Academy of Sciences at Paris, recommended to those exposed to a dele- terious atmosphere some simple thing as a screen to be placed before the organs of respiration so as to intercept the insalubrious particles mingled with the air they breathe. His paper, although confined to those local causes of epidemics which prevail in districts to which his personal observation had extended, is so replete with information, and so corroborative of the efficacy of the measure which I am desirous to extend to animal effluvia, as well as to miasmata arising from vegetable decomposition, that I shall, perhaps, be pardoned if I avail myself of some of the facts which he adduces. J am led to intrude these remarks upon your notice at this time more particularly from the circumstance of my “ suggestion” having been condemned by a_ medical work * with an asperity, ‘‘ not to use a harsher term,” I was not altogether prepared to expect, nor do I feel conscious of having at all deserved it. But the use of “¢ ______ scalping knives instead af pens,” may, without much impropriety, be conceded to the faculty ; I am, therefore, content to allow this great “ northern hight,” the reviewer, (who, by the by, gravely tells the world that contagion is an “ animal product,” and afterwards expresses, in the very same page, his ignorance of its properties ! +) the triumph of his irony ; while I will oppose to his “ want of faith” that “ test of * The Edinburgh Medical and Surgical Journal, No, 61, p. 621, 622, + Ibid, p. 620, 1820.] Use of Gauze Veils as Preservatives from Contagion. 13 truth,” experience, which he so confidently challenges. I will now pursue the arguments of M. Rigaud de V’Isle. “ Miasmata,” he says, “ possess such a gravity that they can never rise in the atmosphere unless assisted by a lighter body, which carries them into. 2t.” In support of this, he says, the air which is very unhealthy at Montalto, Corteno, and along all that coast, stretching to the south as far as Terracina, becomes salubrious on Mount Argentaro, which rises above Orbitello. The villages of la Tolfa, and the habitations situated above Civita Vecchia on the Cimic hills, afford a very agreeable and healthy abode, though situated in the centre of that region of desolation. The same is the case when we rise above the village of St. Felice on the mountain of Circe to the palace of Theodoric above Terra- cina; to,the villages of Sega and Sermoneta, perched perpendi- cularly above the Pontine marshes on the rocks of the Lepine mountains ; also at Monte Fiascone above the lake of Bolsena, above the villages of Valentano, Capo di Monte, Martha, &c. A little further eastward, on the insulated rock of St. Orestes, the inhabitants of the village, which is built on its side, enjoy the best health ; if they descend, disease attacks them, and common fevers make their appearance ; and a little lower down, for instance at Sandreva, they will have putrid fevers ; and still lower down, they will die. The observations of some eminent travellers support these remarks. ‘‘Miasmata,” he continues, “have no smell by which they can be distinguished. They may be separated from the odorous substances with which they seem to be most intimately blended.” Of the peculiar odour emitted by stagnant waters, he adds, it has something disagreeable and sickly, which seems to warn us not to. approach places where it is perceived ; it may, however, be inhaled without any ill effect in certain seasons of the year. I have myself been several times exposed to it. In 1810 and 1811, in passing the numerous ponds which cover the sea coast of the ecclesiastical state, at Maccharese, Ostia, Foliguano, in the Pontine marshes, which I have repeatedly traversed in various directions, I have always perceived this peculiar smell, without sustaining any inconvenience from it. ‘The following year, on the contrary, on a very hot day in the beginning of September, among the ponds of Vauvert, between St. Giles and Aigues Mortes, in Languedoc, I was suddenly seized with nausea and a feeling of sickness, which lasted several days, though I remarked at the time that no kind of odour was emitted by the marsh. He asserts, from experience, that “ it is much more Gangerous to inhale bad air in the night than in the day time. Ail the hours of the day or of the night are not attended with equal risk. The least critical moment is when the heat is greatest and the sun hichest above the horizon. The most dangerous is that which accompanies the setting and that which . precedes the rising of the sun.” ‘This observation, which applies 14 Mr. Bartlett’s further Observations on the [Jan. to all times and places, proves to demonstration the union o miasmata with aqueous vapours; the former are heavy ; the latter, ossessing extreme levity and dilatibility, lend them wings. Ratified in the middle of the day by the heat, the more elastic and lighter vapours must then occupy more space in the atmosphere; the miasmata which they carry with them must also, at such times, be more widely diffused; we do not, therefore, inhale them in such large doses in the same volume of air, and conse- quently cannot m those hours be so much affected by them. M. Rigaud de I’Isle proves that miasmata are much less subtle than the air, or the principle of smells ; since air and odorous effluvia penetrate into every place, whereas miasmata are stop- ped and expelled by various obstacles. ‘‘ The interposition of a forest, a mountain, a high wall, or even of a mere cloth, may also co-operate inthis separation, and preserve us in a variety of circum- stances from the pernicious effects of the air charged with deleterious miasmata.” The arguments of the non-contagionists have, 1 conceive, been too ably refuted to require an additional exposition of their fallacy. Were, however, further proofs necessary, the cireum- stances which attended the too early removal of the restrictions upon the inhabitants of Marseilles, when the plague raged there in 1720; and the fatal effects which followed the temerity of the students of medicine at Edinburgh, some years since, during the prevalence of the Infirmary fever, would sufliciently demonstrate it. It is also, I think, equally clear that contagion can be com- municated by means of the respiratory organs only ; this opinion experience hourly confirms. The Edinburgh Review for March, 1819 (pp. 421, 422), with all its caution in giving an opinion on questionable data, thinks it probable that conta- gion “‘ may be conveyed into the stomach by the saliva; or it may be absorbed by the skin zm some instances; but we are convinced that by jar the most ordinary way is inhalation by the lungs.” That the skin does not possess sufficient powers of absorption, cr the means of secreting pestilential virus, is proved by the circumstance that all animal poisons (not excepting that of snakes or the saliva of mad dogs), being innocuous, by mere contact with the skin alone ; of course, I except those cutaneous and other disorders which are not communicable by any other means. Admitting, therefore, and it is not too much, that the elements of contagion, as de l’Isle proves, are disseminated in’ conjunction with aqueous vapours, the efficacy of any measure for its prevention must depend upon the resistance it opposes to the passage of humidity. Now, how much soever the editor of the Edinburgh Medical and Surgical Journal may question the capability of gauze veils as preventives, Mr. Murray’s communi- cation (for which I feel much indebted to that gentleman), mm your number for September, most satisfactorily demonstrates that they actually will resist the passage of moisture. An expe- 1820.] Use of Gauze Veils as Preservatives from Contagion. 15 riment which | lately tried myself also confirms this. Over a given surface of boiling water I suspended two pieces of sea- weed, each weighing four grains, and measuring an inch square; one piece was enclosed in a single envelope of gauze; the other merely attached to a thread at the same elevation. After the lapse of 15 minutes, the latter was found to have gained a grain in weight, while the other scarcely exhibited a sensible difter- ence! I also submitted two thermometers (the one surrounded by gauze, and the other not) to different degrees of atmospheric temperature ; as well as over cold water, in a warm room, when a considerable evaporation must have been going on; but | always: found a variation to exist between the two. Hence, asit is well known that heat and moisture are the parents of putrefac- tion, it is more than probable that they are the generators of those epidemics which exist with greater or less virulence, in every. quarter of the globe. But to recur to the remarks of the Edin- burgh Medical and Physical Journal. “ Mr. B.” says the writer (alluding to the inference which I had deduced from data, he conceives, “ exceedingly loose and inconclusive ; not to apply. a harsher term’’) “is so fond of remote analogies, that we wonder he did not hit upon the fact of gauze thrown over fruit-trees being a protection to the tender blossoms from the hoar-frost of the mornings and evenings.” I beg to assure the learned gentle- man who has so kindly furnished me with the argument, that it had not escaped my observation ; and currants are to be seen at the present moment in a gentleman’s garden in this place as fresh beneath a common net (which was the only thing made use of to preserve them from “ the winds of heaven,” which might otherwise have “ visited them too roughly ”’) as they were when in season ; while those exposed to the same atmosphere, with- out that protection, were withered up months ago. Want of faith in the efficacy of any measure must be respected from the regard due to opinion ; but what can be said for the consistency of those who can condemn a measure as “ hypothetical,” as founded on analogies “ loose and inconclusive,” and yet recom- mend it! Yet such is the case, for “ notwithstanding,” says the work alluded to, “‘ our declared want of faith in its efficacy, we are desirous that Mr. Bartlett’s suggestion:should be tried.” The ease of my little girl, which I noticed in a subsequent letter, and which appeared in your number for July, is considered even by this fastidious critic as worthy of remark. To that instance I have to add a second, whereim I subjected the same child (having taken a similar precaution) to actual contact with another child which had a full eruption of the measles on it at the time without any ill effects resulting from it. _ I cannot close this article without referring to another profes sional work, the London Medical Repository for July, wherein the learned editors (Drs Uwins, Palmer, and Gray,) thus speak 16 Berzelius on a new Mineral Body, [Jan. of my suggestion: ‘We consider this idea might be adopted with propriety, and probably with effect.” I must confess, without presuming too much, that I look upon the favourable opinions of such men as I have named as no common sanction to the measure I have proposed; and I have only once more to express a hope that it will undergo the test of experiment upon a scale that will either confirm its utility, or disprove its efficacy. I have the honour to be, Sir, Your very obedient servant, J. M. Barrett. ArticLe III. Researches on a new Mineral Body found in the Sulphur extracted from Pyrites at Fahlun. By J. Berzelius. (Concluded from vol, xiv. p. 427.) 10. Combination of Seleniuret of Hydrogen with the Bases of the b Hydroseleniurets. Tue seleniuret of hydrogen possesses the same properties as the sulphuret and telluret of hydrogen; it changes the blue colour of litmus to red; unites as an acid with those bases whose radicals have a stronger affinity for oxygen than that of hydrogen ; and reduces the others to the state of metallic sele- niurets. The soluble hydroseleniurets have the taste, and like- wise to a certain degree the smell, of liver of sulphur, and cannot by these characters be distinguished from the hydrosulphurets ; but they have a deep red or orange colour, and in this respect approach the hydrotellurets. But I must observe that the colour of these last is much more beautiful, and has a tinge of purple, like red wine; while that of the hydroseleniurets has a tint of yellow, and approaches the colour of strong ale. The ‘hydroseleniurets produce spots upon the skin, which are black, brown, or yellow, according to the intensity of the solution, and which cannot be removed by water. I cannot determine whether this colour belongs to the hydro- seleniurets as essentially as it does to the hydrotellurets, or whether it be owing to an excess of selenium dissolved by the hydioseleniuret. I melted selenium with an excess of potassium; the combination was attended with an explosion by which a great portion of the mass was lost ; but what remained gave an orange-red colour, though there was a disengagement of hydrogen during its solution. This ‘observation seems to prove that at least the alkaline hydroseleniurets are coloured. But I ought to observe that I did not repeat this experiment, though it in some measure failed. 1820.] extracted from Pyrites at Fahlun. 17 An experiment made with lime seems to prove the contrary of that made with potassium. I passed in a suitable vessel a current of seleniuretted hydrogen gas through a portion of lime water, taking care to exclude the atmospheric air completely. The liquid became at first muddy, and deposited a small quantity of red powder. The clear liquid remained colourless, though a great excess of seleniuretted hydrogen gas was passed through it. ‘The first precipitate was merely seleniuret of lime, whose hydrogen had been oxidized by the air contained in the lime water. The colourless liquid left in a phial, which I considered as hermetically sealed, began, after two days, to become red at the surface without any precipitation, and the colour increased till it spread over the whole liquid. This effect being at an end, a brownish pellicle of seleniuret of lime began to form on the liquid, and small crystals of the same substance swam against the sides of the phial. After three weeks, the liquid had again become colourless. The explanation of this phenomenon is easy. The hydroseleniuret of lime in contact with the air is decomposed ; but the resulting seleniuret remained combined with the undecomposed part, constitutiag a seleniated hydrose- leniuret. This combination having at last reached its point of saturation, the decomposition of the hydroseleniuret occasioned the precipitation of seleniuret of lime, partly in the form of a pellicle, and partly in crystals. The colourless liquid from which this last was deposited contained still lime in solution. This proves that seleniuretted hydrogen can neutralize a greater quan- tity of base than selenium alone. The same is the case with sulphur. The best method of producing the hydroseleniurets is to dis- solve seleniuret of iron in muriatic acid, and to make the gas pass into a Woulfe’s apparatus, in which the gases are dissolved, or mixed with water. NSeleniuretted hydrogen gas is absorbed much more rapidly and completely than sulphuretted hydrogen gas, and we do not lose so much of it as of this last. The hydroseleniurets are decomposed by the contact of air, _ and the selenium is deposited pure from those which have an alkali fora base. It is generally deposited at the surface in the form of a pellicle, which, on the upper surface, is smooth, metalline, and of the colour of lead. The under surface has a deeper grey colour, and a crystallized texture. If the decom- aii takes place slowly, without agitation, in a vessel which as more depth than breadth, the selenium is deposited in crystal- line vegetations on the part of the glass turned towards the light. The danger with which I considered experiments with sele- niuretted hydrogen gas to be attended prevented me from obtaining the hydroseleniurets in a dry state. The only base with which I have made an experiment is ammonia; but it did not succeed to the degree that I expected. Into a small glass filled with mercury, I passed dry ammoniacal gas till the vessel Vou. XV. N°I. B 18 Berzelius on a new Mineral Body, [Jan. was half filled with it. I then introduced seleniuretted hydrogen gas which had passed through a tube filled with anhydrous muriate of lime. The two gases formed a white smoke, which was soon deposited both on the mercury and the glass, and formed a mass of a pale-red colour, in which no traces of erys- tallization could be observed by the microscope. I cannot decide whether the red colour depends upont he presence of a trace of air mixed with the ammoniacal gas ; but that circumstance is at least: possible. The fixed salt, when dissolved in water, gave that liquid a deep-red colour. Barytes, strontian, lime, and magnesia, all form soluble hydro- seleniurets. The hydrate of magnesia mixed with water, through which a current of seleniuretted hydrogen gas is passed, is dissolved easily by means of an excess of the gas. Thesolutions of the other earths mixed with hydroseleniuret of ammonia form flesh-coloured precipitates, with the exception of alumina, which gives a precipitate of a deep-red colour. As the liquid retains no trace of seleniuretted hydrogen, it is to be presumed that these precipitates are real hydroseleniurets. All the metallic solutions are precipitatzd by the alkaline hydroseleniurets. The precipitates formed in the salts of zinc, manganese, cerium, and probably likewise of uranium, are hydroseleniurets. They are speedily decomposed by the access of air, and their pale-red colour becomes at the same time much deeper. The salts of the other metals are reduced to metallic seleniurets, and the precipi- tates which they produce are black or dark-brown, and assume the metallic lustre when strongly pressed by a polished hema- tites. Before quitting this subject, I must be allowed to make an observation relative to the nomenclature of these combinations. Chemists have begun in the English and French nomenclatures to call the combinations of sulphuretted hydrogen with bases hydrosulphates, to indicate the same theoretical relation between sulphuretted hydrogen and sulphuric acid, which, in the new hypothesis, respecting the nature of oxymuriatic gas, is consi- dered as established between hydrochloric (muriatic) acid and chloric acid. But without entering into any discussion respect- ing this last hypothesis, I think I may state that the new names given to sulphuretted hydrogen gas and its combinations with bases are contrary to the spirit of the nomenclature ; since, when hydrogen is taken away from hydrosulphuric acid and from the hydrosulphates, the residuum is not sulphuric acid and sulphates, but sulphur and sulphurets. I think, therefore, that the old name expresses the nature of the substance which it is intended to indicate much better than the new ; and that this change or nomenclature has been made without sufficient reason, This is the reason why in this memoir I have not adopted the new names, either for the hydrosulphurets, hydroseleniurets, hydro- tellurets, or for a variety of other substances ; and J think that 1820.] extracted from Pyvites at Fahlun. . 19 owe cannot be too much on our guard against adopting and pro- - pagating changes, which are not necessary in a nomenclature once admitted, since long custom renders it difficult to correct even a bad nomenclature. It will be, perhaps, objected to me that sulphuretted, seleniuretted, and telluretted hydrogens actually possess some of the principal characters of acids. 1 ‘allow this. But what confusion in the nomenclature would be produced if we thought proper to call every substance an acid which in a combination may act the part of an electro-negative body ! Do we call every substance an alkali which is capable of acting the part of an electro-positive body; that is to say, a base ? 11. General Observations relative to the Properties of Seleniuar. The existence of a body whose properties constitute, so to speak, the transition from the non-metallic combustible bodies to the metal is surely a very interesting phenomenon ; while this body possesses some of the characteristic properties of the metals, for example, the metallic lustre ; it is destitute of others equally essential, for example, of the power to conduct electricity and heat. In fact, as there is no positive line of separation between the chemical properties of these two classes of bodies, it is probable that none ought to exist between their external properties. We have seen that selenium is more analogous to sulphur than to any other body, and next to sulphur, it resembles telluriuny; so that it lies between these two bodies. But it is from its properties that we must determine in which of the classes we must place it, whether among the metals, or along with sulphur, hosphorus, boron; that is to say, the class of substances to which I have ventured to give the name of mefalloids. In itself it is indifferent in which of the two classes we place it, since the limits between them are not determinable, and since selenium possesses to such a degree the characters of both, that we may place it with equal justice in either of the two. The metallic lustre and the specific gravity have been considered as the cha- - racteristics of the metals ; but the last of these has ceased to be a character, because we are now acquainted with metals which are lighter than water. Nothing remains but the lustre; and I believe that if sulphur and phosphorus possessed the metallic lustre; nobody would hesitate to place them among the metals. As’selenium possesses this property in a high degree, and as it must of necessity be placed in one of the two classes, | conceive that we may arrange it in preference among the eleciro-negative metals, that is to say, among those which produce acids. It will begin the series in making the transition from sulphur and - phosphorus to arsenic. The number of simple combustible bodies has been lately " augmented by three ; two of which with equal, ifnot with greater B 20 _ Berzelius on a new Mineral Body, [JAN. reason, may be considered as oxides, which it has been hitherto impossible to reduce; while the third has a problematic exist- ence. These bodies are chlorine, iodine, and fluorine. To render the simplicity of these bodies more probable, advantage has been taken of their supposed analogy with sulphur and phosphorus. It is evident that in proportion as more bodies are discovered and compared with these last, this analogy must either increase or diminish in probability. This is the reason that induces me to compare selenium with sulphur, chlorine, iodine, and some other bodies. Sulphur and selenium, on one side, unite with the metals; and these combinations, which, for the most part, still preserve some of the external properties of metals, retain likewise the combus- tbility of their radicals. The sulphuret and seleniuret of potassium and sodium are soluble in water. They decompose it at the same time, and produce hydrosulphurets and hydrosele- niurets. Chlorine and iodine, on the other side, combine likewise with the metals; but their combinations have generally the same characters as the anhydrous sulphates, phosphates, and arse- niates. The radicals, at least the most combustible, have lost their combustibility : the chloride and iodide of potassium and sodium do not unite with oxygen; do not decompose water ; and do not form hydrochlorates and hydriodates (unless it he pretended that the’ chlorides of potassium and sodium decom- pose water with the production of cold; while the chlorides of calcium and barium decompose it and produce heat). On the contrary, the chlorides of copper, tin, and gold (and of several other metals, which are incapable of decomposing water, either alone, or in the state of sulphurets, or mixed with the strong acids), decompose water, and produce hydrochlorates. There is, therefore, no analogy between sulphur and selenium on the one side, and chlorine and iodine on the other, since they produce entirely opposite phenomena. Sulphur, selenium, and tellurium, combine with hydrogen, and produce particular acids, which are gaseous and very weak. It had been long cbserved that sulphur and tellurium, notwithstand- ing the difference in their physical and chemical properties, form -combinations with hydrogen of characters astonishingly analo- gous. We now find a third body with which hydrogen forms a compound, having the same-smell, the same taste, and the same properties, as the two preceding ones. This class of acid bodies gives with all the oxides, whose radicals have a stronger affinity for oxygen than hydrogen has, a particular kind of salt, which preserves the taste, and in part even the odour of the acids ; though they are less capable of neutralizing the bases than other acids. The oxides, whose radicals have a weaker ailinity for oxygen than that of hydrogen, are decomposed by these acids. The result is water, and a combination of the radi- 1820.) extracted from Pyrites at Fahlun. 21 cals. These facts lead us to presume that the hepatic taste and smell, from being peculiar to sulphur, are common to that class of acid bodies, as well as to their combinations with bases ; and that an hepatic taste and smell are as essential to the hydracids and to their combinations with alkalies, as the acid taste and smell are to the strong oxacids, and the saline taste to their neu- tral combinations with alkalies. 1, therefore, think it very probable that an alkaline salt destitute of the hepatic taste does not contain an hydracid; and, on the contrary, if the taste be saline, that it contains an oxacid. By extending these consider- ations still further, we find that the oxacids, whose names termi- nate in ows, give to their alkaline salts a peculiar taste by which we recognise the acid; for example, the sulphites and the phos- phites. Further, another class of oxacids very weak, and very indistinctly acid, as the tungstic and antimonic acids, the oxide of tellurium, &c. give to their compounds with the alkalies a metallic taste; so that each class appears to have general common properties by which the class can in some measure be known. Chlorine and iodine combine lixewise with hydrogen; but these combinations are very strong acids, and have their taste and smell purely acid. These acids have the peculiar property of being able to reduce, by means of their hydrogen, potash and soda, and of forming chlorides and iodides, whose pure saline taste is entirely analogous with the combination of the strong oxacids with the alkalies. On the other hand, the hydrogen of these acids does not reduce the oxides of copper, bismuth, gold, &e. with which the hydrochloric and hydriodic acids combine without decomposition. Thus we perceive that the analogy of these hydracids with those of which we have just spoken is entirely null. I thought it proper not to omit these comparisons, because they constitute an addition to the circumstances, which sooner or later will give us more satisfactory information respect- ing the nature of muriatic, iodic, and fluoric acids. We have seen the great analogy between sulphurand selenium, and this analogy continues even in their combinations with oxygen; so that both form acids but little volatile. However, these acids have not the same analogy with each other as thei- radicals have. Sulphuric acid belongs to that numerous class of acids which have three atoms of oxygen, and possesses in con- sequence the manner of combination of these acids. Selenic acid, on the contrary, belongs to the small class of acids which, without terminating in ous, contain only two atoms of oxygen; and in this respect has a strong analogy with carbonic and boracic acids. Like these acids, it does not form neutral salts with alkalies. In the salt, in which the acid contains twice as much oxygen as the base, the alkali re-acts; and in those in which the acid contains four times as much oxygen as the base, it is the acid which re-acts. We find the same phenomenon in 22: Berzelius on anew Mineral Body, (Jan. the borates and the carbonates; yet boron and carbon have no, aualogy with selenium. It is true that boron may be combined with the alkalies; but I do not know that any one has hitherto produced a boruret of hydrogen or borurets analogous to the metallic sulphurets and seleniurets. Every one knows. that, carbon does not combine with the alkalies, and in a very small proportion with the metals ; and, finally, that carburetted hydro- gen has not the hepatic taste and smell, nor possesses the proper- ties of an acid. Selenium has no analogy, as far as its chemical characters are concerned, with arsenic and phosphorus. It is obedient to the general laws of the combination of oxidated bodies, from which the two former deviate in so remarkable a degree. Their com- binations with hydrogen, though possessing several properties of; the gases containing much hydrogen, are not hepatic, and do not possess the properties of acids. We may say that arsenic is to phosphorus what selenium is to sulphur; but in fact there is very little analogy between these two pair of bodies. 12. Researches into the State in which Selenium is found in the Mineral Kingdom. By the care of my friend M. Gahn, I received, during my: experiments, a portion both of the pyrites of Fahlun, employed) in the manufacture of the sulphur, and of the impure sulphur itself. The pyrites was partly pure and partly mixed with blende,. galena, chlorite, and several other foreign bodies. By roasting either before the blow-pipe or on a furnace, it was impossible to perceive any smell of horseradish. I dissolved 10 grammes of this pyrites in nitromuriatic acid. The solution was precipitated by sulphuretted hydrogen gas, and the precipitate was again dissolved in nitromumatic acid. The liquid was then saturated with potash, filtrated, and evaporated to dryness. The salt obtained was mixed with sal-ammoniac, and exposed to a high temperature. After having dissolved the saline mass, selenium remained ; but its quantity was so small that it could not be weighed. The impure sulphur gave, by a similar treatment, about 0:0015 of its weight of selenium. This quantity, small as it is, would furnish a considerable annual quantity of selenium, did not the ether impurities, and particularly the arsenic, hinder it from being employed. The purified sulphur furnished traces of sele- nium scarcely perceptible. The experiments with the pyrites of Fahlun appeared to show that the selenium is scattered through the whole substance of the stone, although in a quantity infinitely small. However, as it sometimes happens at Fahlun that the roasting of the copper pyrites exhales a strong odour of horseradish, we may presume that a mineral containing selenium occurs here and there in ai 1820.] extracted from Pyrites at Fahlun. 23 more notable quantity ; and we must: hope that it will one day be in our power to recognize and collect it. M. Gahn had shown me some years ago a small piece of a mineral which he had received under the name of Swedish ore of tellurium. 1 made some fruitless attempts to extract tellurium from it, and at the time that I thought myself entitled to say that it contained none of that metal, M. Gahn made me perceive the strong odour of horseradish which it exhaled when heated before the blow-pipe. The small quantity which we possessed being consumed in our attempts to obtain tellurium, | was obliged to- defer the examination of it till 1 could procure a greater quantity of it. During my experiments on selenium, [ recollected this pre- tended ore of tellurium, and having applied to the person who had sent the specimen to Gahn, I was fortunate enough to obtam a quantity sufficient for an analysis of it. As far as I can judge from the specimens of this mineral which I have seen, it possesses the following properties : Its colour is leaden grey ; it has the metallic lustre; the frac- ture is granular and subcrystalline, without its being possible to discover other signs of crystallization. It is soft, and may be cut with a knife; where cut, it has the brilliancy of silver. It receives impressions from the hammer. « Before the blow-pipe, it melts, and gives out a strong smell of horseradish, leaving a small grey metallic button, which conti- nues long to exhale the smell. If we fuse it with borax, that saline substance becomes copper-green, and a brittle metallic button separates, which is a seleniuret of silver. A solution of this mineral in boiling nitric acid mixed with cold water gives a white precipitate, which is seleniate of silver, and which has probably led to the notion that it was an ore of tellurium. The mineral is mixed with carbonate of lime and with black parts, which, when scratched by the knife, assume the metallic lustre, melt with difficulty before the blow-pipe, giving out the odour of selenium, dissolve, when fused with borax, giving it the green colour of copper, and exhibit no traces of reduced silver. The black parts appear to be a serpentine imbibed with seleniuret of copper. For analysis I selected pieces as pure as possible, and I divided them into very small grains, to be sure that they con- tained no visible portion of these foreign bodies. a. One hundred parts of the mineral were dissolved in boiling nitric acid. The solution was diluted with boiling water, and then filtered. The liquid which passed fell into a solution of muriate of soda, and the matter which remained upon the filter was washed with dilute boiling nitric acid as long as the hquid that passed through continued to trouble the solution of the muriate. In this last solution, muriate of silver had precipitated, which, al 24 Berzelius on a new Mineral Body, [Jan. after being well washed, dried, and fused, weighed 50:7 parts, equivalent to 38°93 parts of metallic silver. On the filter remained a mixture of silica and stony matter foreign to the composition of the dissolved mineral. When heated to redness, it weighed four parts. b. The liquid from which the silver had been separated was. precipitated by sulphuretted hydrogen gas. The precipitate was redissolved in nitromuriatic acid, and the acid liquid concentrated till the whole nitric acid was decomposed. It was then diluted with water, and sulphite of ammonia added. It became gradually muddy, and ofa cinnabar-red colour. After some hours, it was boiled, adding from time to time small portions of sulphite of ammonia. The boiling was continued two hours to be quite sure of precipitating the whole of the selenium. Collected on a filter, dried, and almost fused on the filter, it weighed 26 parts. c. The liquid separated from the selenium and deprived by boiling of the residual sulphurous acid, was precipitated by the subcarbonate of potash. The green precipitate being washed, dried, and heated to redness, became black, and was peroxide of copper. It weighed 27 parts, equivalent to 21:55 parts of metallic copper. This oxide, dissolved in muriatic acid, and mixed with an excess of ammonia, dissolved completely with the blue colour of copper. The alkaline liquid-from which the car- bonate of copper had been separated, had still a green tinge.. It, was concentrated, acidulated with muriatic acid, and, by means of an iron plate, 1:5 part of copper was still separated from it, which makes the whole of the copper to amount to 23°05. The liquid precipitated in b by sulphuretted hydrogen gas, being deprived by boiling of the excess of gas, was mixed with caustic ammonia, which occasioned a yellow precipitate, which, when dried, weighed 1:8 part. It was a mixture of oxide of iron and alumina. he liquid from which it had been separated was mixed with an excess of subcarbonate of potash, and evaporated. to dryness. The saline mass, being dissolved in water, left a white earth, which, when dried, weighed 3:1 parts. Sulphuric acid, being mixed with this earth, occasioned an effervescence with the production of gas. The liquid separated from this last and evaporated became gelatinous, and deposited silica, It appeared also to contain magnesia; but I neglected it because these earths were obviously foreign to the metallic mineral. The result of the analysis was : PRVer «cbs Lev Gche la, disk tei aeetOe Copper ......% bh AR ow slips Selemivmsd, coils wid weeee Sao Foreign earthy matter...... 8-90 Bosdic'. cided; 02 usmingee ete 100-00 1820.) extracted from Pyrites at Fahlun. 25 This great loss must be partly attributed to the carbonic acid united to the lime, in a great measure to the selenium which it is difficult to separate completely, and partly to the unavoidable loss in this kind of experiment. The 38-93 parts of silver combine with 2:86 oxygen. The 23-05 of copper require to form the protoxide 2:91 parts of oxy- gen; and the 26 parts of selenium in order to be acidified require 10°5 parts. We see from this that the two metals absorb | an equal quantity of oxygen, and that the selenium absorbs twice as much; that is to say, that they are combined in the same proportion as in the neutral seleniate of silver and the pro- toseleniate of copper. Hence the chemical composition of this mineral may be expressed by the following symbol; 2 Cu Se + AgSe*. It may be requisite to recall to the attention of the reader another mineral recently described by MM. Hauss- man and Stromeyer,* to which they have given the name of silber-kupfer gians, and the composition of which, according to their analysis, is 2 CuS + AgS?*; so that there exists native a double sulphuret analogous to the double seleniuret, which I have just described. ‘These two minerals, therefore, ought to be placed beside each other in the mineralogical system. As this mineral requires a name not derived fromits composi- tion, for the sake of shortness, I have called it eukairite (from evxaipos, opportunus) ; because I consider the accidental discovery of selenium in the mineral kingdom just at the time that I had finished my experiments on this interesting body, as a peculiarly fortunate circumstance. I could not at first discover whence this pretended ore of tellurium came ; but having consulted M. Hisinger, to whom Swedish mineralogy lies under such obligations, he immediately knew that the mineral came from an old abandoned copper mine at Skrickerum, ix the parish of Tryserum, in Smoland, and that specimens of it were occasionally observed in old collections under the name of native bismuth of Skrickerum. I examined afterwards the specimens from that mine found in the collection of the College of Mines at Stockholm, and had the satisfaction to find avery good specimen of eukairite. It is surrounded by a serpentine of a black or dark-green colour, which, at the point. of contact with the eukairite, is penetrated by seleniuret of RPDET, in which only traces of silver can be observed. This seleniceferous serpentine is found here and there in the mass of the eukairite, as I remarked above. The quantity of seleniuret of copper in the serpentine diminishes in proportion as its dis- tance from the eukairite increases. In its neighbourhood, it becomes metallic when rubbed with a hard body ; but this does not happen at a distance from the eukairite ; and when the interval amounts to a line and a half, all trace of selenium disappears. * Gilbert’s Annalen der Physik, 1816, vol. x. p, 111. ae Berzelius on a new Mineral Body, [Jan. This serpentine, when treated with concentrated muriatic acid, is decomposed ; but the liquid contains neither selenium nor copper: these two bodies remain undissolved with the silica—a proof that neither of them existed in the mineral in the state of oxide. On the other side, both nitric and nitromuriatic acids dissolve the two metals before they have begun to attack the serpentine. Inthe mine of Skrickerum, we find the following minerals along with the eukairite: yellow sulphuretted copper, sometimes iridescent, sometimes in its natural state, and some- times with a compact and tarnished fracture ; carbonate of lime; serpentine partly black, partly dark-green, and partly pale- green; and anthracite mixed with carbonate of lime in very thin beds, which intercept the anthracite at the distance of one-sixth, or one-third of a line. The discovery of selenium at Skrickerum occasioned a more attentive examination of what might be found from that mine in collections. M. Swedenstierna found beautiful specimens of a carbonate of lime, which had great black spots in it, and he sent me a specimen of it for examination. I observed that these spots were formed round natural clefts in the carbonate, and when the mineral was divided through these clefts, the new surfaces were found covered with a white metallic vegetation. A small plate of the black mass surrounding the clefts, being seen through a compound microscope, presented a metallic vege- tation, which penetrates the substance of the limestone in every direction. , I separated the metallic substance from the lime by dissolving this last in muriatic acid. A considerable black mass remained, which was dissolved in nitric acid. The solution, being mixed with nitrate of barytes, did not give any precipitate. Muriate of soda precipitated nothing ; but after an interval of some minutes, the liquid began to assume a milky aspect, and in some hours gave traces of a precipitate. The liquid, which was blue, being mixed with an excess of ammonia, did not let any thing fall ; but with subcarbonate of potash, it formed subcarbonate of copper, and I then separated from the residual liquid, rendered acidulous by muriatic acid, selenium, by means of sulphite of ammonia. Hence the mineral which produces these black stains is a sele- niuret of copper without any mixture of silver. Likewise the metallic vegetation found in the clefts contains no traces of silver, as I ascertained by detaching a small quantity which had been dissolved in nitric acid and then mixed with muriatic acid, without any other result than a feeble opalescence. It is well. worth remarking that it is only the seleniuret of copper which is found filtered into the porous parts of the car- bonate of lime, as well as of the serpentine. Hence it seems to follow that the seleniuret of copper was more liquid than the eukairite at the time when these stony masses assumed their actual form. 1820.] extracted from Pyrites at Fahlun. 27 Seleniuret of copper has a paler colour than eukairite, and has almost the appearance of native silver. It is soft, may be hammered and polished, and then assumes the colour of tin. Even the black spots of the carbonate of lime assume a metallic polish when filed or rubbed against a hard body. When heated in the requisite vessel, it does not yield selenium. Hence it isa protoseleniuret. We have then two species of minerals containing selenium; both of which in the chemical system of mineralogy belong to the family of copper; namely, se/eniuret of copper = Cu Se, to which I think it superfluous to give any other name than the chemical appellation; and eukairiie = 2 CuSe + Ag Se*. ArtIcLE IV. Answer to Mr. Venables’s Queries respecting Cyder-making. By Chemico-Medicus. (To Dr. Thomson.) SIR, Bolton-raw, Piccadilly, Oct.9, 1819. Tue attention I have paid to the making of cyder, and other vinous liquors, in this country, has emboldened me to answer the queries of your correspondent, the Rev. Mr. Venables, rela- tive to fermentation of the juice of the apple. Vo the first Query.—I know of no method of neutralizing the malic acid, except by an alkali, which, of course, would injure the cyder. Ifthe apples which yielded the juice were not ripe, it certainly would be advisable to add to it, previously to ferment- ing it, a quantity of sugar, otherwise the fermented liquor will be so weak that it will soon run into the acetous fermentation. If this addition be not made, a portion of some alcohol, as brandy, rum, or malt spirit, should be added, to keep the cyder in a vinous state. Brandy, I know, is made use of hy some cyder-makers, near Ledbury, in Herefordshire, with a view of preventing it passing beyond the vinous stage, or, as they say, to preserve its richness ; and those makers are particularly celebrated for mak- ing superior cyder. The addition ofa spirit, after the first stage of fermentation, I consider to have the same effect as that of sugar previous to fermentation; the advantage of the latter arising from a production of a spirit which preserves the cyder in a vinous state. Another circumstance which powerfully con- tributes to this end is the grinding of the kernels of the apples, as suggested, I think, by Mr. R. Paine Knight, the peculiar bitter quality of which not only gives the cyder a fine flavour, but very powerfully tends to preserve it in a vinous state. Some months ago I was led to make experiments with the saccharine 28 Answer to Mr. Venables’s Queries (JAN. roots of this country by grinding them with apples, in consequence of seeing in a periodical work, entitled The Gazette of Health, the beet-root recommended to be added to the apples at the time of grinding, with the view of imparting saccharine matter. The cyder was certainly much euriched by the addition, but I was not a little disappointed in the colour, which I expected to have found beautifully red. The colour imparted to the recently expressed juice by the beet-root was entirely destroyed by the fermentative process. The cyder had a peculiar earthy flavour, which was not relished by cyder drinkers. Both the parsnip and the carrot considerably enriched the juice of the apples, and did not affect the flavour of the cyder. Itis worthy of notice that in Herefordshire and in Devonshire the farmers add a considerable ° quantity of water to the apples at the time of grinding them, which they contend renders it rough. The water is generally in such quantity as to constitute more than one-half of the expressed liquor. This is the cyder generally drunk in both counties, and preferred by the farmers for their own use. Hearing a farmer, who made about 800 hogsheads annually, obstinately contend that an addition of water to the apples, when in the mill, increased the strength of the cyder, | was induced to examine the article thus made, and also that which was not strengthened by adding water. The former I found did not afford half the quantity of spirit as the latter. To the palate the former, as the farmer contended, appeared stronger and rougher. On examin- ing it, I soon discovered that this supposed strength depended on the presence of vinegar! The fact was soon evident, that the expressed juice thus diluted speedily ran into the acetous fermen- tation, and that instead of cyder, they were drinking a dilute vinegar ; and to it the natives give a preference. Indeed cyder in aproper vinous state, they condemn, supposing, on account of its being somewhat sweet, that it has been ‘ doctor’d.” Second Query.—The efiect of boiling the malic acid, as it exists in cyder, will be a dissipation of the spirit, and conse- quently the liquid will soon become vinegar. Your correspond- ent’s query is by no means clear to me—I presume he means the boiling of cyder, and not the pure (concentrated) malic acid, which he must be aware can undergo no change by boiling. Third Query.—I know of no other means of clearing the liquor before fermentation from impurities than by straining it. During fermentation much passes off through the bung-hole, and much is deposited. Ifit remains foul after fermentation, it may be cleared by isinglass. Fourth Query.—I cannot speak positively as to close fermen- tation. Mr. R. Paine Knight recommends close fermentation, by which, he says, the flavour of the apple is preserved. I have tasted very fine cyder that was thus fermented, but a quantity of brandy was added to preserve it in a vinous state. If the fermen- tation be conducted in a wide vessel entirely open, the alcohol 1820.] respecting Cyder-making. 29 will fly off, and the liquor will rapidly advance to the acetous fermentation. I think it right, however, to allow the carbonic acid gas to pass off. Fifth Query.—The lees of cyder is only the feculent part of the liquor deposited. I should suppose that no person could expect such an article to contain as much spirit as clear cyder. Sixth Query.—-That cyder is weakened by racking is very evident, because the spirit flies off. This process is often neces- sary to quiet cyder, by getting rid of carbonic acid gas. After parting with this gas and a portion of alcohol, the feculent matter diffused through it is generally deposited. see no reason why cyder should not be made in this country equal to many of the Rhenish wines. The juice of the apple contains a sufficient portion of acid, and the malic acid is assuredly as pleasant as that of any grape. The expressed juice is deficient in saccharine matter, and this deficiency may be made up by adding that of other vegetables. For this purpose, I prefer germinated wheat. By grinding this article with the apples, the juice is considerably enriched ; and, when properly fermented for three days with a little yeast (about half a pint to 120 gallons), the cyder will be found equal to the wine commonly drank in Germany. {n many parts of Herefordshire and Worcestershire, the crab is very abundant. The fruit the farmers seldom collect ; and when they do, they grind it for making verjuice, which is sometimes used for vinegar, but generally kept for bruises and sprains. This acid differs only from that of the apple in strength. If the juice be, therefore, diluted with water, and a quantity of sugar added (in the proportion of an ounce to a pint), the fermented liquor will be equal to the best cyder. I have known this liquor pronounced excellent cyder by good judges of the article. There is in the cyder counties a strange prejudice against the employ- ment of sugar in making of cyder. he vulgar suppose that the article is rendered weak by it, and that the only object for which - it can be used is to render it palatable. Such cyder, they say, is only fit for ladies. If you deem this communication worthy a place in your jour- nal, | shall occasionally contribute my mite towards its laudable object. I am, Sir, your obedient servant, Cuemico-Mepicus. On reperusing the foregoing letter, I find I have omitted to notice one remark made by Mr. Venables respecting the expo- sure of the pulp of the apple to the atmosphere. This is parti- cularly recommended by Mr. R. P. Knight, who asserts that the juice thereby acquires an increase of saccharine matter. The experiments I have made certainly confirm this statement ; but cyder so made, I have thought, sooner runs into the acetous fermentation, probably in consequence of attracting oxygen. 30 Mr. Booth on the Cornea of the Eye. [Jan. ARTICLE V. On the Cornea of the Eye. By Mr. Booth. (To Dr. Thomson.) SIR, Barnet, Nov, 20, 1819, As the pages of your Annals are not generally occupied by anatomical subjects, it might be supposed the following observa- tions were misplaced. But as they refer to the structure and functions of the eye, and a peculiar action of that organ upon light; they are so connected, perhaps, with the other more immediate objects of your journal as to allow of their insertion. It is a well-known anatomical fact, that if a moderate degree of pressure be applied to the sides of an eye after removal from the socket, its axis becomes increased ; the crystalline lens is thrust forward ; the cornea becomes distended by means of the -aqueous humour; and, at the same time, is rendered: perfectly opaque. This opacity is not permanent; for the moment the pressure is removed, it regains its former transparency, and this effect may be continually varied as we vary the pressure. I was induced to examine this phenomenon rather more minutely, from having lately observed that it was not produced in very-fresh eyes; and hearing it remarked that if all the layers of the cornea, except the last, are removed, this effect does not take lace. I had originally considered this opacity to depend upon a peculiar polarity, given by means of the pressure: to the aqueous humour contained in the anterior chamber of the eye, and which might become more obvious a short time after death on account - of some change that might have taken place inthe nature of the fluid. This, however, could not be the case, as the opacity ceases on the removal of the several. layers of the cornea, although an equal degree of pressure be applied. It must, there- fore, evidently depend upon some change produced by the pres- sure of the aqueous humour upon that membrane. The cornea - cannot, in this instance, be in its natural state ; and some mecha- nical or morbid alteration must previously have taken place before the opacity could have been produced. I removed several cornee from eyes and placed them betweenslips of glass ; upon applying pressure, those which had been taken from recent eyes suffered no change; while the others became opaque. ‘The opacity was the same by transmitted as by reflected light. This rendered it certain as to its depending upon the cornea, and to some change that must have taken place in it. After death, a transudation of the aqueous humour takes place through the layers of the cornea, and it is to the quantity of this fluid contained between the layers that the opacity of the comea may be referred. Whether the opacity depends upon pressure com- 1820.] — Mr. Booth on the Cornea of the Eye. 31 municated by the layers of the cornea to the particles of aqueous fluid contained between them; or by a mutual action upon each other, I am at present unable to say. But the fact is evident that if pressure be applied to a cornea containing aqueous humour between its layers, a peculiar polar arrangement takes place producing perfect opacity. I should not suppose any change to have taken place in the nature. of the cornea; for even in the fresh eye, the effect may be produced, by applying a remitted pressure for a short time—pumping, as it were, the fluid into the layers of the cornea. If the tunica conjunctiva be removed, tue fluid will be seen exuding from the surface in the form of dew, and the effect gradually takes place. It is more obvious when the conjunctiva is not removed, on account of its being a more impervious membrane, and by offering a resistance to the passage of the humour allows a greater accumulation of it between the layers of the cornea. When all the layers are removed except the last, the whole structure upon which the phenomenon depended becomes destroyed ; for in this case, the fluid having only one layer to pass through, it escapes without any degree of pressure, and without producing any effect ; whereas when more than one layer exist, the fluid becomes entangled between them, and in this situation is affected by the pressure from behind. In Mr. Wardrop’s Anatomy of the Hye, he mentions a case of opacity resulting from a larger secretion of aqueous fluid than usual; and being induced to puncture the cornea to allow some of it to escape, he found the transparency instantly restored. The opacity, in this instance, most likely depended upon some morbid peculiarity of the cornea, communicated to it by the disease existing in the contiguous membrane of the aqueous humour, and which had primarily produced an increase of that fluid. ‘This morbid peculiarity allowing of a transudation of the fluid between its coats, which, being acted upon by the pressure from the increased quantity of aqueous fluid, produced the opacity. This case would appear to depend more upon the morbid state of the cornea than the pressure ; for we have often an increase in the quantity of aqueous fluid in the anterior chamber of the eye, producing pressure, but not opacity. By causing various fluids to pass between the layers of the membrane, I was in hopes of arriving at a more certain know- ledge of the nature of this polarity ; my results, from the imper- fect manner in which my experiments were performed, were too various to place much confidence in them. As I intend pursuing the subject, should I be able to arrive at any thing determinate, I may again obtrude myself upon the pages of your journal. ‘Lam, Sir, your most obedient servant, Tuomas 8, Bootn. 32 Dr. Henry’s Experiments on the Gas from Coal. [Jan. ArTIcLE VI. Experiments on the Gas from Coal, chiefly with a View to its Practical Application. By William Henry, M.D. F.R.S. &c. (Concluded from vol, xiv. p. 344.) On the Pwrification of Coal Gas. Tue chief impurities mingled with the gas from coal, which it is desirable and practicable to remove before applying it to use, are carbonic acid and sulphuretted hydrogen gases. The former is of little importance ; but the latter imparts to the coal gas, when unburned, a very offensive smell, resembling that of bilge water, or the washings of a gun-harrel, and the inconve- nient property of tarnishing silver plate ; and during combustion gives rise to the same suffocating fumes (sulphurous acid) which are produced by the burning of a brimstone match. The most obvious method of absorbmg both the carbonic acid and the sulphuretted hydrogen is to bring the»recent gas into contact with quicklime ; and the cheapness of that substance, and faci- lity of applying it, led me, several years ago, to propose it for the purpose.* It has since, I believe, been suggested that the sulphuretted hydrogen may be removed by chlorine; but a suffi- cient objection to this agent is, that it would also separate the most valuable part of the»product, the olefiant gas. The trans- mission of the gas through ignited tubes has also been proposed ; but it is a well-known property of both the varieties of carburet- ted hydrogen, that they deposit charcoal, when strongly heated ; and M. Berthollet has shown that the amount of this effect is proportionate to the increase of temperature.} Some persons practically engaged in lighting with gas have, to my knowledge, been led, by the increase of the quantity of gas which is obtained. by passing it through red-hot tubes, to imagine that an advan- ‘tage is thus gained ; and they have not been aware that the gas, when thus treated, sustains a much more than proportional loss of illuminating power. The quantity of quicklime required for the absorption of a cubic foot of carbonic acid, or of the same volume of sulphuretted hydrogen gas, will be found on calculation not to exceed 1050 ‘grains, or about 21 ounces avoirdupois. A volume of coal gas containing a cubic foot of each of those impurities will require, therefore, at least five ounces of lime applied in the best possible manner. But it is never found in practice that the whole of any gas, when sparingly diffused through another, can be taken out. entirely, without using much more of the appropriate agent than, from its known powers of saturation, might have been deemed equivalent to the effect. The proportion employed by Mr. Lee * Phil, Trans. 1808, p. 303. + Memoires dela Soc, d’Arcueil, iti, 154. 1820.] Dr. Henry’s Experiments on the Gas from Coal. 35 is five pounds of fresh burnt lime to 200 cubic feet of gas. The: lime, after the addition of the quantity of water necessary to reduce it into powder, is passed through a sieve, and then mixed with a cubic. foot (about 74 wine gallons) of water. This is found to be enough to purify the gas sufficiently for ordinary purposes ; but it still retains a minute proportion of sulphuretted hydrogen, which, from the shade of colour produced in the test, may be estimated at about —,1,,th of its volume. For some purposes, the same gas is therefore washed a second time with a similar proportion of fresh lime, which, without being removed from the cistern, is again employed to give the first washing to another quantity of fresh gas. After the second purification, the gas produces no change whatever in the test, which preserves its perfect whiteness, thereby demonstrating the complete removal of the sulphuretted hydrogen. In this state of purity, its odour also is so much diminished as scarcely to be at all offensive. In order to ascertain whether any, and what portion of olefiant or carburetted hydrogen gas is lost by the action of the lime liquor, I compared, with the greatest care, the products of the combustion of the recently prepared gas, and of the same gas after one and two washings with lime and water. Consumed oxygen, Gaye carb. acid, 100 measures of the unwashed gas.. 190 ........ 108 Gas once washed .......... SANE UA anon: nl wien SED Twice washed..... aydnitirs speyh ante seis Ail ested ahaa LI The frequent repetition of similar experiments fully satisfied me that the fresh prepared gas from coal does in fact sustain, by agitation with lime liquor, a loss of combustible matter amount- ing to about 8 or 10 per cent.; but that the secorid washing is not attended with any further appreciable loss. I found also that the recent gas, by being kept a fortnight in bottles completely filled with it, and well stopped, so as to exclude all agency of the water in which they were inverted, was diminished in com- bustible matter about half the foregoing amount. On the other hand, gas which had been washed with lime liquor suffered no change, when kept under like circumstances for an equal time. {ft is probable, therefore, that what is separated from the unwashed gas, whether by keeping or by the action of lime liquor, is chiefly condensable matter, partly perhaps an etherial oil, and partly a substance which it is desirable to remove, rather than to allow it to be deposited in a solid form, in the small Pipes, or in the burners. The little effect of the lime liquor on the olefiant gas, which I had not anticipated, admits, however, of being satisfactorily explained on known principles. Water and similar fluids absorb, according to Dalton, about one-eighth, according to Saussure, about one-seventh, of their volume of olefiant gas. The utmost Vou. XV. N° I. . 34 Dr. Henry's Experiments on the Gas from Coal. fJan. quantity, therefore, which a cubic foot of lime liquor, acting’ upon pure olefiant gas, could absorb, would be one-seventh of a cubic foot. But agreeably to a law discovered by Mr. Dalton, and explained and confirmed by my own experiments,* a cubic foot of lime liquor, when brought into contact with 36 cubic feet of olefiant gas mixed with 164 cubic feet of other gases, can absorb only about one-fifth of one-seventh, or 3th of a cubic foot of olefiant gas. This quantity, which does not exceed ath part of the olefiant gas present in 200 cubic feet of the best coal gas, is too trifling a loss to be discoverable by experi- ment, or to be worthy of being regarded in practice, even when doubled by a second washing. It is, therefore, consistent with general reasoning, as well as with experiment, that the washin of coal gas with a due proportion of lime liquor should entirely remove the sulphuretted hydrogen gas and other offensive ingre- dients, without abstracting an appreciable quantity of either of the carburetted hydrogen gases. It is nevertheless important that the quantity of water, employed in washing the gas, should not be mcreased beyond what is necessary to give the mixture due fluidity, because, under equal circumstances, the power of water to absorb a gas is in direct proportion to the quantity employed. Such are the principal circumstances that occurred to me as requiring to be investigated, and to be at the same time capable of affording results that may admit of general application where- ever coal gas is employed as a source of light. There are others of more limited utilty that may be left to be determined by those persons who are interested respecting them; such as the prefer- ence due to different varieties of coal as sources of gas, and sometimes even to other inflammable substances, which, on account) of local situation, may be entitled to preference over coal. The facts which have been stated supply also data for deciding other questions, which may be suggested by circum- stances of partial interest ; for example, whether it may not be adviseable, in some cases, to collect only the first portions of gas; or, if all be collected, to reserve different portions apart from each other, and to apply them to appropriate uses. Thus, when coal gas is conveyed in portable gasometers to a distance (as is now practised by Mr. Lee in supplying his house two miles: from the manufactory+), it will be important to select that gas, which in a given volume has the highest illuminating power, and which, therefore, requires vessels of the smallest capacity for its * Nicholson’s Journal, Svo. vii. 297, and Thomson’s Annals, vii. 214. + A small carriage upon springs conveys two square close gasometers made of wrought iron plates, and each containing 50 cubic feet of perfectly purified gas, equivalent together to about 6 Ibs. of tallow. ach gasometer weighs about 160 Ibs, and has a valveat the bottom, which is opeved by the upright main pipe, the moment the gasometer is immersed in the pit. ‘The strength of one man is found to be sufficient for the labour of removing the gasometer from the carriage ta its place. 1820.] Dr. Henry’s Experiments on the Gas from Coal. 35 conveyance. Having, I hope, furnished documents for solving questions of this sort, I shall proceed to describe in what man— ner the facts were ascertained. Method of Analysis. 1. Determination of the Proportions of Carbonic Acid and Sulphuretted Hydrogen Gases in Coal Gas.—In experiments formerly made on this subject, I employed the agency of chlorine to condense both these impurities, and estimated how much of the absorption was due to each, by a rule which I have stated.* Recent experience, however, has led me to distrust this method; and after comparing the effects of several other agents, by expe- riments on mixtures of known composition, I now prefer the white carbonate of lead, precipitated from acetate of lead by car- bonate of ammonia without heat, and, therefore, fully saturated with carbonic acid. This precipitate it is better not to dry, but, after washing it sufficiently, to leave it under as much water as will give it, when wanted for use, a due degree of fluidity. This. mixture may be applied by means of a tube of the capacity of a cubic inch, divided into 100 equal parts, and accurately ground into a short and wider piece of tube, which ought not to contain more than three or four-tenths of that quantity. The wider tube being filled with the fluid carbonate of lead, and placed with its mouth upwards under water, the graduated measure full of gas is fitted to it ; and the gas and liquid are brought into contact by alternately inverting the two tubes, all violent agitation being carefully avoided. The sulphuretted hydrogen is thus absorbed, and the carbonic acid, being left untouched, is afterwards taken out from the same portion of gas by a similar use of solution of pure potash. 2. To ascertain the Proportion of Olefiant Gas in the Residue left by Potash.—From 25 to 30 hundredths of a cubic inch of chlorine gas are passed into a tube of the diameter of about {ths of an inch, accurately divided into hundredths of a cubic meh; and the volume of the chlorine is noted when actually in the tube, to avoid errors from its absorption in rising through the water. To this is admitted half a cubic inch (equivalent to 50 measures) of the gas under examination, and the mixture is left, excluded from the direct light of the sun, and perfectly quiescent, for 15 ramutes. At the expiration of this time, the remainder is noted, and the diminution which has taken place being divided by 2, the quotient shows. the quantity of olefiant gas in 50 mea- sures ofthe mixture. This process, | am aware, however, does not give results of perfect accuracy ; for, in addition to other sources of fallacy, 1 find that chlorine begins to act on carbu- retted hydrogen much sooner than is generally supposed,+ though * Phil. Trans. 1808, p, 295. t While this sheet was passing through the press, I have noticed a passage im c2 36 Dr. Henry’s Experiments on the Gas from Coal. [Jan. within the period mentioned, and in such narrow tubes, it does. not occasion a sensible diminution of bulk. The method described may, therefore, be considered as affording a tolerably near approximation to the proportion of olefiant gas ; and as all the varieties of coal gas were subjected to the test under pre- cisely the same circumstances, the errors must have been of nearly the same amount in all cases, and cannot materially inter- fere with the fair comparison of the different specimens of coal gas, so far as respects their proportion of olefiant gas. 3. To ascertain the Quantity of Combustible Matter in gas which had been deprived only of sulphuretted hydrogen and car- bonic acid, a mixture of the gas with a due proportion of oxygen gas was fired by the electric spark over mercury. This method 1 preferred to slow combustion, carried on with the apparatus: which I have described in the Philosophical Transactions for 1808, solely because, when a great number of experiments are necessary, as in this inquiry, the method of detonation is attended with a great saving of time. But on all occasions where only few experiments are required on gases of great com- bustibility, I prefer slow combustion, both on account of greater safety to the apparatus, and, from.the quantities that may be consumed, of greater accuracy also. Whenrapid combustion is practised, I believe that, on the whole, more accurate results are gained by firing the gas at one operation properly conducted, than at two. The latter method seems to have been preferred by M. Berthollet ; but so far as my experience goes, it is more apt to precipitate charcoal from the gas. To burn each measure of the early and more combustible pro- ducts of gas, [ employed from three to four measures or upwards of oxygen gas, the degree of purity of which had been aseer- tained. The volume being noted after firing, and again after” "agitating the residue with liquid potash, the last diminution: showed the quantity of carbonic acid. The gas left by potasle was next analyzed by combustion with a due, proportion of pure hydrogen,* which showed how much of the residue was oxygen, aad how much azotic gas. If more azote was found than had deen introduced as an impurity of the oxygen gas, it was consi- dered as having formed a part of the combustible gas. A single experiment on any kind of gas was never relied upon; and to ensure accurate results, the same gas was fired with different proportions of oxygen. Deducting the pure oxygen found in the residue, from its quantity at the outset, the volume of oxygen gas was learned, which had been spent in saturating a given measure of combustible gas. Mr. Brande’s Manual of Chemistry (p. 156 n.), from which it appears that the speedy action of chlorine on carburetted hydrogen had been observed by Mr. Faraday, 4 The methed of doing this is given in my Elements of Chemistry, yol. i. chap, ¥- sect. vi, 1820.] Dr. Henry’s Experiments on the Gas from Coal. 37 In gases free from all admixture with carbonic oxide, it is easy to know how much of the oxygen consumed has been spent in saturating the charcoal; for as oxygen gas by conversion into carbonic acid suffers no change of volume, the quantity which has combined with the charcoal is exactly represented by the volume of carbonic acid produced by the combustion. For example, as 100 measures of olefiant gas afford by detonation 200 of carbonic acid, 200 measures of oxygen must have united with the charcoal of the olefiant gas. But beside these 200 measures, an additional 100 measures of oxygen are found to be consumed, and these must have combined with hydrogen, the other ingredient of the gas, the volume of which in its full state of expansion would be 200 measures, as determined by the fact, that oxygen gas uniformly takes for saturation double its volume of hydrogen gas, and no other proportion. Nature of the Gas from Coal. The opinion which I formerly advanced on this subject,+ though opposed by writers of so much authority as M. Berthollet and Dr. Murray, still appears to me to be much more probable, than that the varieties of gas from inflammable substances, which may be almost infinitely-diversified by modifications of temperature, are, as those philosophers suppose, so many dis- tinct compounds of hydrogen and charcoal, or of hydrogen and charcoal in combination with oxygen. The reasons that induce me to abide by my original view of the subject are the following: 1. We are acquainted with two distinct and well characterized compounds of hydrogen and charcoal, in one of which a given weight of charcoal is united with a certain quantity of hydrogen, and in the other with double that quantity. Besides these two, no other compound of those two elements has been hitherto proved to exist. 2. It is inconsistent with experience that two bodies which, like hydrogen and charcoal, unite by an energetic affinity, should combine in all possible proportions. On the contrary, it is to be expected from analogy in general, and from that of the com- pounds of charcoal and oxygen in particular, that hydrogen and charcoal unite in few proportions only, and in such a manner that these proportions are multiples or divisors of each other by some entire number. 3. All the phenomena may be satisfactorily explained by supposing the gas from coal, and from other inflammable sub- stances, to be mixtures of this kind. For example, referring to the one hour’s gas in the first table, we shall find that it contains, in 100 measures, 18 of olefiant gas, which require for combus- tion 54 measures of oxygen, and afford 36 of carbonic acid. The same gas contains also 771 measures of another inflammable gas, * Nicholson’s Journal, 8vo. xi. 68. 38 Dr. Henry’s Experiments on the Gas from Coal. (San. in the combustion of which 210 — 54 = 156 measures of oxygen have been spent, and which have afforded 112 — 36 = 76 mea- sures of carbonic acid. This is as near an approach as can be expected to the properties of carburetted hydrogen, the 774. measures having consumed very nearly twice their bulk of oxygen, and given an equal volume of carbonic acid. We may, therefore, consider the early products of the gas from cannelas a mixture of about one volume of olefiant gas and four volumes of carburetted hydrogen.* The early product of gas from Clifton coal does not admit of being thus theoretically resolved into a mixture of olefiant and carburetted hydrogen gases only. For after deducting from the oxygen consumed (164 measures) that spent in saturating the olefiant gas (10 x 3 = 380) we have only 134 measures of oxygen . left for the combustion of 90 measures of inflammable gas. These 90 measures, it appears, afford 91 — 20 = 71 measures of car- bonic acid. This portion of the gas does not, therefore, answer to the characters of carburetted hydrogen, since it neither gives an equal volume of carbonic acid, nor consumes a double volume of oxygen. In this case and a variety of similar ones, we can only at present explain the phenomena, by comparing them with hypothetical mixtures of the different known gases. As an example, I shall describe the particulars of the combustion of the first product of Clifton coal, and endeavour to explain the results in the manner which has been suggested. Measures of the gas........ 11 Mixed with oxygen ........ 39 = 37 pure oxygen + 2 azote. Dotal.. Sheena: POLO O ED ee CE a ene eed 5 OEE 19 132 4 281 In this stance, the hypothetical constitution coincides even more nearly with the facts than in the former case. It must, indeed, be acknowledged that the explanation rests on hypothesis only; but it is on an hypothesis which is perfectly consistent with a copious and increasing induction of facts, all tending to establish a limitation to the proportions in which bodies combine ; while the opposite explanation is at variance with this general law of chemical union. sary apparatus, which was found, from long disuse, to have become unfit for the purpose. So faras respects the practical objects of this paper, the omission is ef no consequence. 40 Analyses of Books. {Jan. ArticLe VII. ANALYSES or Books. Philosophical Transactions of the Royal Society of London, for 1819, Part J, Tuts part contains the following papers : ¥. The Croonian Lecture—On the Conversion of Pus into Granulation, or new Ilesh. By Sir Everard Home, Bart. V.P.RS. In the last volume of the Transactions, Sir Everard Home endeavoured to explain how coagulated blood became vascular. Carbonic acid gas, he informed us, is extricated at the moment of coagulaticn. This gas gradually lengthens into a tube, which is immediately covered by a coat, and thus converted into a blood-vessel. He is of opinion that the same process goes on during the conversion of pus into granulations, or new flesh. Pus, he tells us, is analogous to the serum of blood. At first, it contains no globules, but they gradually make their appearance in it whether it remains on the surface of the sore, or be removed upon some other surface. Mr. Bauer has observed that the same formation of globules takes place in the serum of blood ; thus showing the analogy between serum and pus. The paper is taken up im describing the appearances which are perceived upon the surface of a healing sore, when left for about a quarter of an hour exposed to the atmosphere. The coating of pus coagulates, globules of carbonic acid gas make their appearance init. These are speedily converted into numerous anastomesing vessels filled with red blood. HI. On the Laws which regulate ihe Absorption of Polarized Light by Doubly Refracting Crystals. By David Brewster, LL.D. F.R.S. Lond. and Edin. If to one side of a rhomboid of colourless calcareous spar we fasten a circular aperture of such magnitude that the two images of it appear distinctly separated when viewed through the spar, ‘we shall find that when the spar is exposed to common light, the two images are equally colourless, and of the same intensity in all positions; so that the ordinary tmage contains half the quantity of transmitted light, and the extraordinary image like- wise half the quantity of transmitted light. When the rhomboid is exposed to polarized light, the intensities of the two pencils are together equal in every position to the whole transmitted light. Hence the rays which leave one of the images by a change of azimuth pass over into the other image. When the same experiment is tried with certain specimens of yellow calcareous spar, the results are different. The two images differ both in colour and intensity; the extraordinary image 1820.] Philosophical Transactions for 1819, Part I. 41 having an orange-yellow hue, while the colour of the ordinary image is yellowish-white. This difference of colour is related to the axis of the crystal, and increases with the inclination of the refracted ray to the short diagonal of the rhomb. It is a maxi- mum in the equator, while along the axis the two images have exactly the same colour and intensity. The author shows that there is aninterchange of rays. The extraordinary force carries off several of the yellow rays from the ordinary image ; while, at the same time, the ordinary force takes to itself some of the white rays from the extraordinary image. "When the rhomboid is exposed to polarized light in the posi- tion in which the ordinary image vanishes, the extraordinary image is orange-yellow, and in the position in which the extraor- dinary image vanishes, the ordinary image isa yellowish-white. It follows from this, that a portion of the ordinary pencil was absorbed in the first position, and a portion of the extraordinary pencil in the second position. The author examined coloured crystals of zircon, sapphyr, ruby, emerald, beryl, rock crystal, amethyst, tourmaline, rubel- lite, idocrase, mellite, phosphate of lime, phosphate of lead, and. observed similar appearances. Now these are a great proportion of all the coloured crystals with one axis of double refraction at present known to exist. The general phenomena of absorption in crystals with two axes are nearly the same as those with one ; but the quantity of light which the ordinary and extraordinary forces interchange is regulated by new laws depending on the situation of the incident ray with respect to the two axes of double refraction. The author explains these laws, and gives a table of the different colours resulting from these absorptions in a variety of coloured crystals with two axes. The author concludes from his observations that the colouring particles of crystals, instead of being indiscriminately dispersed. throughout their mass, have an arrangement related to the ordi- nary and extraordinary forces which they exert upon light. In some specimens, the extraordinary medium is tinged with the same colouring particles, and with the same number of them as the ordinary medium; but in other specimens of the same mineral, the extraordinary medium is either tinged witha different number of particles of the same colour, or with a colouring matter entirely different from that of the ordinary medium. In certain specimens of topaz, the colouring matter of the one medium is more easily discharged than that of the other. Hence the reason why such topazes become pink when exposed to a red heat. ILI. Observations on the Decomposition of Starch at the Tem- perature of the Atmosphere by the Action of Airand Water. By Theodore de Saussure, Professor of Mineralogy in the Academy of Geneva, Correspondent of the Royal Institute of France, &c. © 42 Analyses of Books. _ Plan. The author of this memoir is of opinion that an examination of the action of vegetable substances on each other and of the effects produced upon them by the action of air and water, is _ the best method of investigating various effects of vegetation ; or _ at least if it does not answer that purpose, it will lead to important experiments respecting-the theory of fermentation. Starch had scarcely been examined under this point of view, or only indi- rectly, and in a way quite insufficient to enable us to deduce the requisite consequences. It had been observed that the seeds of corn formed sugar during germination; and that this does not _ happen unless they be impregnated with water, and air have access to them. Hence it was concluded that the oxygen gas which disappeared, producing carbonic acid gas, was the princi- pal agent in the conversion of the starch into sugar. Vogel had exposed a mixture of starch and sugar to the action of a boiling heat for four days. The mixture became very fluid. It was filtered. The filtered liquid being evaporated left a bitter muci- lage, which had not the least of a saccharine taste. A horny looking matter remained on the filter. Kirchoff has discovered that if one part of dry pulverized gluten be mixed with two parts of starch made into a paste with water, and the mixture be digested for 10 or 12 hours at the temperature from 122° to 167°, the starch is partly converted into sugar. Hence he has con- cluded that the conversion of starch into sugar takes place during germimation. Such was the state of our knowledge before the experiments which Saussure relates in the present paper. He mixed together 20 grammes of the best wheat starch, and 12 times the weight of water, so as to form a thin paste. This was put into a large flat cylinder forming a layer to the depth of two centimetres (0°8 inch nearly). It was covered by a large receiver, below which the atmospherical air had easy access, and left at rest for two years in a place in which the temperature rose as high occa- sionally as 721°. At the end of this period, it was a grey- coloured liquid paste, covered with mucors, and almost without smell. Itproduced no change on vegetable blues, and could no longer be employed to paste substances together. After being dried in the temperature of the atmosphere, its weight was con- siderably diminished. If we suppose its original weight to have been 100, it was reduced to 76-2 dried at the temperature of the atmosphere, or to 80-46, supposing both dried at the tempera- ture of boiling water. ‘This residual matter was carefully analyzed, and found to consist of the following substances : Sugar, Gum, Amidin, Starchy lignin, Lignin mixed with charcoal, Starch undecomposed. 1820.] Philosophical Transactions for 1819, Part I. 43 The sugar possessed the characters of the sugar made from starch by means of sulphuric acid. The gum possessed the following properties : It was transpa- rent, and almost colourless, when formed without the contact of air ; but when the starch became covered with mucors, the gum was yellow, and rather too soft to be reduced to powder. One hundred parts of this gum at 66°, when exposed to the heat of 212°, lost 11:75 of their weight. It does not absorb moisture from the air, nor is it altered by exposure to the atmosphere; but its aqueous solution becomes gradually putrid, depositing a thick mucous matter. It is insoluble in alcohol, but soluble in water in every proportion. Two'parts of water and one of the gum form a very fluid solution, but it becomes viscid and thready when the weight of the gum exceeds that of the water. A solution of one part of the gum in ten parts of water is neither precipitated by acetate of lead, nor subacetate of lead, nor the decoction of nutgalls, nor silicate of potash. It does not alter the colour of the infusion of litmus. It does not alter the colour of aqueous solution of iodine. It is slightly precipitated by barytes water. It does not form mucic acid when treated with nitric acid. It possesses most of the characters of the gum into which starch is converted by roasting. Saussure has applied the term amidin to a substance which he considers as intermediate between gum and starch. The word is formed from the French term amuidon (starch). As it is con- trary to rule to permit the nomenclature of chemistry to be obscured by words borrowed from living languages, it is obvious that if a new term be requisite for this substance, we must call it amylin (from the Latin word amylum), used by the moderns for starch. It is obtained from the residue left by the sponta- neous decomposition of starch after it has been treated with a sufficient quantity of cold water to dissolve every thing soluble in that liquid. Boiling water dissolves the ainylin, and it may be obtained by evaporating the solution to dryness. It is obtained either in irregular, opaque fragments, or of a yellow- pale semitransparent brittle substance, according to the mode of conducting the evaporation. It is insoluble in alcohol. Cold water dissolves about one-tenth of its weight of it, and forms a colourless and very fluid liquid. Water of the temperature of 144° dissolves it in any proportion, and retains in solution, after cooling, a much greater proportion than can be dissolved in cold water. The decoction may be concentrated till it contains one- fourth of its weight of amylin in solution without becoming muddy or gelatinizing on cooling, which is not the case with starch. When the liquid is more concentrated, the amylin pre- cipitates in part on cooling in the state of a white opaque matter; but it is redissolved on heating the water to 144°. In this Tespect it approaches inulin. The solution of amylin containing one-tenth of its weight of this substance, assumes a blue colour, 44 Analyses of Books. - Far. when mixed with the aqueous solution of iodine, and presents with this re-agent all the effects of starch, It is coagulated into a white paste by the subacetate of lead; but not by the neutral acetate. It is copiously precipitated by barytes water, but not by lime water, nor decoction of nutgalls. It dissolves in the aqueous solution of potash. This liquid is very fluid, and wants the viscidity of the solution of starch in potash. The weak acids precipitate the amylin from it with all its properties. Alcohol likewise throws down a copious precipitate, which, however, retains a portion of the alkali, and does not strike a blue with iodine till an acid is added to it. The starchy lignin was obtained from the residue of the spon- taneous decomposition of starch, after that residue had been deprived of every thing soluble in cold water, hot water, alcohol, and very dilute sulphuric acid, by digesting it in 10 times its weight of an alkaline ley containing one-twelfth of its weight of potash. A brown liquid solution is obtained, from which dilute sulphuric acid precipitates the starchy lignin under the form of a brown, light combustible substance, having the lustre of jet. It gives a blue colour to the aqueous solution of iodine. This last property, together with its solubility in a weaker alkaline ley, distinguishes starchy lignin from common lignin. During the sportaneous decomposition of starch, the bulk of the air undergoes no change; but a small portion of its oxygen is slowly converted into carbonic acid gas. Fifteen grammes (2312 gr. troy) of starch mixed with 12 times its weight of water produced in two months, in the temperature of 721°, only 50 cubic centimetres (19°68 cubic inches) of carbonic acid ‘gas. Thus the action of the oxygen of the air is confined to the abstraction of carbon. The loss of weight which the starch Sustains is much greater than can be accounted for by the carbon abstracted by the oxygen of the air. Hence the starch must lose a considerable portion of its weight by giving out oxygen and hydrogen under the form of water. To ascertain the difference in the result when the starch was allowed to decompose in the air and in a vacuum, the experiment was repeated both ways for 38 days in a temperature of about 724°. The following table exhibits the results of these two experiments : One hundred parts of starch decomposed without the contaet of air, yielded SUBEE, G 41's s\n 4:0) In eres Shtobait Roa ee weatacd -- 47°4 GMMR. She's els anese st sisiocana Bevan CU) s lakhs 23-0 SUID clas haia as wie SMe 6 2 lt Ghiri ehra eae 8-9 Starchy. emia. o's. a. a - « vip Rea oa bets 10:3 Lignin mixed with charcoal.......... Trace Starch not decomposed. .....esee06. 40 936 1820.] Philosophical Transactions for 1819, Part I. 45 ‘One hundred parts of starch’ decomposed in contact of air _ yielded SUDAN |e sie era jae divi olsipidlal ates! eicelo am aie . 49°7 Grams aes bisisr ski sie sis Sei ities. «cele acai 7, Amylin. ....0..e8. SRY SUAIB SEED whetateco oh 52 Starchy lignin. .....e.. essere ence 9:2 Lignin mixed with charcoal .......... 0-3 Starch not decomposed. .......+.44- 3°8 iw These experiments being repeated with potatoe starch, and continued only for 42 hours, yielded the following products : In vaeuo, ANGUS, dace tace: aye lel Shove tereye ve sa eah-anda tet SOAs ishiasids eroOre ee ee ee wicthalls opanatey-aCacay ks hc Pawan, wee 17:2 SAAMRATED Akh sales nips 00 p's aid Bate Ssh. Gate soles. 17:0 Starchy lignin........ ob pactdtai attefete Masi w bean ohebiovs 4-4. Lignin with carbon. .......... TYACC ais 146 SEL 896 Teg GI TOL £96 oes a TIL 19% 80 09% SI SIL 20 801 G9 088 als le -l2 —[o alee afro 9 OO Sie ae S'S SiGier x “qqnuize ont, hG 9ST #qq 0 Tho 9ee OP L 9 SSI TES 0 T6p 98I 91 8P& Sel" 2 $ho Lge eG Ege 469 GFE 4e8 OPE 49% She cf P81 VG VEE Zo BEE GO FEE 79 GEE 91 981 Ly GLI “yin -1ZB poss3sqQ cS of| ol] off off of] off fo ol} of] off [Ho {Jo {Io {Jo [lo [lo {}o off off flo ol] of x ‘OpNyNTe paadsosqo “Ay Sopny1su0)y ce GL ce GL 86 GL FL 89 PL 89 TG 089 "nN fapnyney cD) O> OS) N OOOO oO yolMuvainy Uva] nd O€ 86 6G IG ai 8) p Ame LG LG LG LG Le oa 8 81 Lt LI al ia uGG 6 Pune 55 1820.] Philosophical Transactions for 1819, Part I. ‘trozI1OT TeInyeu oy} Aq QUI] Lomo] oy} “F ‘“WoTOoHe. 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The author had been induced, from experiments made before the perusal of Malus’s book, to conclude that the polarizing forces extend beyond the surface of the crystal. This led him to repeat the experiments on which Malus’s opimion was founded. ‘The result of the inves- tigation, which overturns the doctrine of Malus, is contained in this paper. If we take a six-sided prism of nitre, and observe a luminous object through two of its clined surfaces that have a good polish, we perceive two distinct and perfectly formed images. If we now roughen these surfaces and cement upon each of them a plate of glass by means of balsam of capaivi, the character of the two images will be greatly changed. The image that has suffered the greatest refraction will be as distinct as before; but the other image will be either of a faint-reddish colour, or wholly invisible, according to the degree of roughness induced upon the refracting surfaces. If we substitute pure alcohol or the white of an egg for the balsam, the least refracted image will become distinct, and the most refracted image will be either a mass of nebulous light, or almost invisible. The reason of this is, that balsam of capaivi has nearly the same index of refraction as the ordinary image, but not of the extraordinary. it therefore removes the roughness of the surfaces as far as the ordinary image is concerned, but leaves the roughness. for the extraordinary image. The index of refraction of alcohol and white of egg is nearly the same as that of the extraordinary image. It therefore removes the roughness as far as the extra- ordinary image is concerned; but leaves it with regard to the ordinary image. Similar experiments were made with calcareous spar and arragonite. The author draws from them the following conclusions : 1. The force of double refraction and polarization extends not only without the interior limit of the ordinary refractive force, but also without the surface of the crystal. 2. The force of double refraction and polarization emanates from the surface of bodies, though its intensity depends upon the inclination of the surface to the axis of the crystal. 3. The ordinary or the extraordinary image may be extin- guished at pleasure in any doubly refracting crystal; and the crystal is thus converted into a singly refracting crystal, lke certain specimens of agate. 4. In soft crystals that do not admit of a perfect polish, the distinctness of any of the two images may be made a maximum, by giving the crystal the best polish of which it is susceptible, and then cementing plates of glass upon its surface by a trans- parent cement of the same refractive power as that of the pencil, 1820.] Proceedings of Philosophical Societies. 55 which is to be rendered most distinct. If it is required to make the two images equally distinct, the refractive power of the cement must be a mean between that of the ordinary refraction and the extraordinary refraction, which corresponds to the angle which the refracted ray forms with the axis of double refraction. 5. All doubly refracting crystals consist of an ordinary and an extraordinary medium alternating with each other, and varying in density according to a law which the author has investigated, but not given in this paper. Dr. Brewster, in the subsequent part of this paper, shows that the change in the angle of polari- zation produced by the interior force, depends on the inclina- tion of the reflecting surface to the axis of the crystal, and also on the azimuthal angle which the plane of reflection forms with the principal section. This half volume terminates with a postscript to Dr. Young’s paper, containing an investigation of the corrections for refrac- tion. This investigation being entirely analytical, I must refer those readers who wish to know the important results obtained by this very acute philosopher to the paper itself, which occupies only four pages. The usual meteorological journal for 1818 is given likewise in this half volume ; the mean results of which are as follows = temperature, 53°5°; barometer, 29°88 inches, at the height of 81 feet above low water at Somerset House. No correction for temperature is introduced, which renders the barometrical heights given in the journal of little or no value. Rain, 11-636 inches. Mean variation of the needle in June, 24° 15’ 45” W. Dip about 70° 51’. ArticLe VIII. Proceedings of Philosophical Societies. ROYAL SOCIETY. Nov. 25.—Dr. Carson’s paper, On the Elasticity of the Lungs, was concluded. After some introductory remarks, comprehend- ing a popular description of the thorax and its contained viscera, the author proceeded to observe that the influence of the elasti- city of the lungs on the circulation of the blood and on respiration, has been overlooked by physiologists. To ascertain the real force of the elastic power of these organs, Dr. C. connected with the trachez of several animals a glass syphon, so placed as to admit of pressure being exerted on the lungs by a column of water contained in it. An opening was then made into the cavity of the chest on both sides, and the height of the column of water in the tube was considered as equivalent to the pressure oA ba A 56 Proceedings of Philosophical Sccieties. [Jane exerted upon it by the elastic power of the lungs. From expe- riments conducted in this manner upon the lungs of the ox, Dr. C. considered it as clearly ascertained that in this animal the zesilience of the lungs is more than equal to a column of water a foot and a half high. Ina still more satisfactory experiment. made upon the lungs of a dog, the column stood at 10 inches. The paper was concluded with some remarks upon artificial respiration, and on the best means of ascertaining the actual quantity of air contained in the lungs. Nov. 30.—On this day the annual meeting for the election of officers for the ensuing year took place, when the following noblemen and gentlemen were elected : President. —Right Hon. Sir Joseph Banks, Bart. G.C, B. &c.. Secreéaries.—W. T. Brande, Esq. and Taylor Combe, Esq. Treasurer.—Davies Gilbert, Esq. There remained of the old Council, Right Hon. Sir J. Banks, Bart.; W. T. Brande, Esq.; Taylor Combe, Esq.; Davies Gilbert, Esq. ; Major-General Sir James Willoughby Gordon, K. C. B.; Sir Everard Home, Bart.; Sir Thomas Staunton, Bart.; William Hyde Wollaston, M.D. ; and Thomas Young, M.D. There were elected into the Council, William Blake, Esq. A.M.; John Earl Brownlow; Charles William Earl of Charleville ; Alex. Crichton, M.D.; Sir Benj. Hobhouse, Bart.; Capt. Henry Kater; Daniel Moore, Esq. ; Right Hon. Sir John Nicholl, Knt. 5 the Rev. Thomas Rackett, M.A.; and the Right Hon. C. Yorke. Dec. 9.—A paper, by J. F. Herschell, Esq. F.R.S. was begun.. It was entitled “On the Action of Crystallized Bodies on Homogeneous Light, and on the Causes of the Deviation from Newton’s Scale in the Tints which many of them develope on Exposure to a polarized Ray.” Dec. 16 and 23.—This elaborate paper was continued. LINNEAN SOCIETY. This Society commenced its meetings on Nov. 2, when a aper, by Henry Thomas Colebrooke, Esq. F.L.S. was begun. t was entitled “On the Waltiedde and Memispermum Fenes- tratum of Gcertner, and divers Menisperma described by Roxburgh.” Nov. 16.—The above paper was continued: Dec. 7.—There were read some Observations on Buxbaumia Aphylla, in a letter from Mr. J. Stewart, Lecturer on Botany in Edinburgh to Sir Joseph Banks. Dec. 21.—Part of a paper, by - Temminck, Esq. was read, entitled “A Description of some new Birds from Newfoundland, in the Society’s Museum.” GEOLOGICAL SOCIETY. June 18.—Some additional remarks by H. I+ de la Beche, Esq. were read. 1820.] Geological Society. 57 In 2 former paper, M. de la Beche gave an account of the fossil animal found in the blue lias of Lyme, usually called the ichthyosaurus, but which has been lately named by Sir E. Home the proteosaurus ; the object of these additional remarks is to point out several species of proteosaurus which have been disco- vered. These are three: the communis, the tenuirostris, and the platyodon. The characters of the species are taken from the form of the teeth and the jaw bone, and the names of the two latter are derived from the shape of these parts. There are probably other species, but they are not yet sufficiently well ascertained. The author gives, from Dr. Leach, a scientific description of the Dapedium politum, a fish with rectangular scales, that has been discovered in the lias of Lyme. Nov. 5.--The reading of Mr. Weaver’s paper “ On the Geolo- gical Relations of the Environs of Tortworth, and the Mendip Range in Somersetshire,” was continued. Nov. 19.—A paper, from Dr. Nugent, was read, entitled << Sketch of the Geology of Antigua.” It was accompanied by a map, sections, and specimens. The author observes that Antigua contains no marks of modern volcanic action ; but many effects of former revolutions. The south and east parts of the island exhibit recent beds of a peculiar calcareous formation, probably cotemporary with those around Paris, and in the Isle of Wight; the surface of these calcareous beds is in the form of rounded hills, like those of the chalk district of England, the highest being about 300 or 400 feet above the ocean. The materials of this formation are not uniform ; a great part of it consists of closely compacted marl, of a bright yellow colour. Through this marl run layers of compact limestone containing shells, calcareous spar, quartz, chalcedony, and agate. Strata of gritstone also run through the marl, composed of quartz, hornblende, jasper, hornstone, and green earth, held together by an argillaceous cement ; this is used in masonry. The marl also contains a smooth-grained calcareous sandstone, which is employed for building. The calcareous formation contains many shells and corallines, both calcareous and silicified; most of them are analogous to those in the neighbouring sea, but it is probable that they have been ap. a in their present situation at a remote period. he marl contains very great quantities of a substance called ground pearl, the nature of which is not well ascertained. The marl also contains both marine and fresh water remains, but they are mixed together ; the silicified and agatized corallines, which are so abundant and so beautiful in Antigua, are very plentiful in the calcareous beds ; they contain no remains of large animals, and no gypsum. Below the calcareous formation, and lying south of it, are extensive irregular masses of coarse flint or chert. They contain a large quantity of shells, chiefly cerithea, filled 58 Proceedings of Philosophical Societies. [Jan. with chalcedony ; the inferior part of these beds contains a very large quantity of petrified wood. Below the marl and chert is a series of stratified rocks which the author calls claystone con- glomerate ; they compose hills that are precipitous on one side, and slope gradually on the other. In small specimens, the rock resembles a clay porphyry, but it has not the usual relations of this rock. It dips at a considerable angle to the north-west ; it contains so much chlorite as to exhibit a green tinge; this is commonly thought to depend upon copper ; but the author attri- butes it either to iron or manganese. The rock acquires a conglomerate appearance from the numerous specimens of petri- fied wood and fossils of all kinds which it contains. The woods are all tropical species, and generally of the palm tribe. The most elevated parts of the island consist of rocks of the newest floetz trap formation; but the author conceives that they are composed ofa very large proportion of boulders included in the conglomerate. A communication was read from Dr. Gmelin, of Tubingen, on the subject of the clinkstone of Hohentwiel, upon which natrolite _isfound. He informs us, that by heating it, he obtained from it a quantity of ammonia ; and he found the same results from some basalts which he tried. ROYAL ACADEMY OF SCIENCES AT PARIS. An Analysis of the Labours of the Royal Academy of Sciences during the Year 1818. (Continued from vol, xiv. p. 229.) An Historical Essay upon the Services and Scientific Works of Gaspard Monge; by M. C. Dupin, a pupil of Monge, and mem- ber of the French Institute —“ G. Monge was born at Beaune in 1746. His progress was such that they gave him the office of Professor of Natural Philosophy in the college at Lyons although he had only begun to study it the year before..... Returning to Beaune in the vacation, he set about the survey of that town. As he had not proper instruments for that purpose, he made some himself. He dedicated his work to the administration of his native place, and they recompensed the young author, as far as the limited finances of the place would allow. . A Lieutenant- Colonel of the Engineers, who happened to be at Beaune, obtained for Monge an appointment as draughtsman and pupil in the Ecole d’Apparailleurs et de Conducteurs des Travaux des Fortifications (equivalent to our Drawing School in the Tower). As he was an excellent draughtsman, his manual dexterity was alone considered. He, however, already knew his own strength, and saw with great indignation the value that was exclusively bestowed on his mechanical talents. ‘I was tempted,’ said he, “a long time afterwards, a thousand times, to tear my drawings, out of spite for the value set on them, just as if | had been good 1820.] Royal Academy of Sciences. 59 for nothing else.’ The director of the school ordered him to calculate a particular case of defilement, an operation in which the relief and groundwork of fortifications is to be combined together with the smallest possible charge, but so that the defenders may be sheltered from the shot of the assailants. Monge abandoned the method hitherto followed, and discovered the first general geometrical method that was known for this important operation. ....By applying, at different times, his mathematical talents to questions ofa similar nature, and always generalizing his manner of conceiving and working them, he, at last, formed a scientific work on the subject; this was his Descriptive Geometry. ....For more than 20 years, he found it impossible to show to the corps stationed at Mezieres the appli- cation of his geometry to carpentry. He was more successful in its application to masonry; he studied with great care the methods hitherto employed, and simplifying them he brought them to perfection by his geometry.” “His scientific works caused him to be appointed Acting Professor of the Mathematics and Natural Philosophy, in the room of Nollet and Bossut ; afterwards he was appointed Hono- rary Professor: he then turned his views towards the study of many phenomena of nature; he made numerous experiments upon electricity ; he explained the phenomena which arise from capillary attraction ; was the creator of an ingenious system of meteorology; he examined the composition of water, havin made that great discovery without having any knowledge of the experiments which had just before been made by Lavoisier, Laplace, and Cavendish. He did not content himself with explaining to his pupils in the theatre of the school the theories of science and their application : he loved to conduct his disciples wherever the phenomena of nature, or the works of art, could render these applications apparent and interesting. He commu- nicated his own ardour and enthusiasm to his pupils, andchanged those observations and researches into desirable pleasures, which would have appeared to be a disagreeable study in the confine- ment of a school, and clothed only in abstract ideas.” “ In order to bring Monge to Paris, he was appointed in 1780 assistant to Bossut, Professor of the Hydrodynamic Course, instituted by Turgot. That he might reconcile the duty of the two places which he now held, he lived six months at Mezieres, and six months at Paris. The same year he was admitted mto the Academy of Sciences ; and on the death of Bezout in 1783, he was chosen to succeed that celebrated examiner of the naval service. The Marquis de Castries invited Monge several times to write another elementary course of the mathematics for the oo of the naval service, but Monge always refused to comply. ezout, said he, has left a widow with no other fortune than her fate husband’s works, and I do not wish to take away the bread from the widow of one who has rendered important services to 60 Proceedings of Philosophical Societies. [Jan science and to his country. The only elementary work which Monge published was his Traité de Statique; and, with the exception of a few passages in which greater rigour might be desirable, the Statique of Monge is a model of logic, clearness, and simplicity.” *« At that period when the public distress called forth all the useful talents and courage of the superior classes to the assist~ ance of their country menaced with invasion, Monge was created Minister of the Marine. He did every thing he could to keep those men who were distinguished for their merit or bravery in France. He even descended to entreaties to procure the conti- nuation of Borda’s services, and he had the happiness to succeed. He was one of the most active men in those scientific services which the preservation of the state required. ‘The construction of the new grinding machines erected in the powder mills at Grenoble was his, and also the drilling machines constructed upon the barges of the Seime. He spent his days in giving instructions and superintending the workmen, and his nights in writing his treatise on the casting of artillery, a work designed for the use of directors of foundries, and for workmen.” “ It was in his course at the Normal School that he first gave his lectures of descriptive geometry, the secrets of which he had not been able to reveal sooner. Another establishment, which had been originally conceived before the Normal School, but which, having had more attention paid to it by the inventors, followed it in the order of execution, realized some part of the hopes which had been looked for in vain on the establishment of the first Encyclopedic School that had been opened in France. Monge brought into it his long experience at Mezieres, and joined to this new and profound views ; he drew up the plan of study, marked out their succession, and proposed scientific methods of execution. Out of 400 pupils originally placed in the Polytechnic School, 50 of the choicest were collected into a preparatory school. Monge was almost the only one that taught these pupils. He remained the whoie of the day among them, giving them, in turn, lectures on geometry and analysis...... exhorting them, encouraging them, inflaming them, with that ardour, that kindness, that impetuosity of genius, which made him explain to these pupils the truths of science with an irresist- ible force and charm. In the evening, when these labours were finished, Monge began others of a different kind; he wrote the sketches which were to serve as a text to his next lectures, and the next day he was to be found along with his pupils at the very moment of their meeting. The good nature of Monge was neither the cold calculation of the sage, nor. even the effect of education; it was a simple benevolence which arose from his happy organization. He was born to love and to admire. His admiration was excessive like his love ; in consequence of which he did not always keep within the limits that cold and unfeeling ———___—— 1820.) Royal Academy of Sciences. a 5 reason would have prescribed. ....As he was the father of his pupils in the school, so he was in camp the father of the soldier.” “In traversing Italy to collect the statues and pictures that had been ceded to France, Monge was struck with the singular contrast between the Grecian monuments of the arts and those of the Egyptians, transported by Augustus and his successors to the shores of the Tiber. The comparative characters of the ancient monuments were the frequent subject of conversation between the conqueror of Italy and the commissary who collected for his country the most precious fruits of victory. Monge con- ceived the idea of extending the domain of history beyond the fabulous ages of Greece; of learning with the certainty of a geometer what were the labours of the ancient sages of the East; of discovering afresh, by the contemplation of their monuments, what had been the processes of their arts, the usages of their public life, the order and the majesty of their feasts, and of their ceremonies.” “« Monge, charged by the General in Chief to carry to the Directory the treaty of Campo Formio, was a short time after- wards placed in the first rank of the literary men who composed the Commission of Sciences and Arts which were to accompany the expedition to Egypt. He was the first that was appointed President of the Institute of Egypt formed on the model of the French Institute. He visited the pyramids twice, he saw the ‘obelisk and the grand ruins of Heliopolis, he studied the remains of antiquity scattered round Cairo and Alexandria. -It was dur- ing a tedious march in the middle of the desert that he discovered the cause of that wonderful phenomenon known by the name of mirage. At the time of the revolt of Cairo, there were in the city only a few detachments of the troops. The palace of the Institute was guarded by the members themselves ; and it was proposed to sally out and join the main guard ; but Monge and $erthollet, considering that the palace contained the books, manuscripts, plans, and antiquities, which were the fruits of the expedition, maintained that it was the duty of the members to guard this precious deposit, and that they ought to defend that treasure at the hazard of their lives.” “« Monge presided in the Commission ofthe Sciences and the Arts in Egypt ; he contributed by his councils to form that wise plan, and by arranging and proportioning the various parts endea- voured to execute it in the utmost perfection.” * Monge had an inimitable method of exposing the most abstract truths, and of rendering them plain by the language of action. Nevertheless it was only by combating with nature that he was able to become an excellent professor: he spoke with difficulty, and almost stammered ; the prosody of his discourse was vicious, for he lengthened some syllables falsely, and short- ened others. His physiognomy, naturally calm, exhibited the 62 Proceedings of Philosophical Societies. (Jan. appearance of meditation ; but as soon as he spoke, he appeared quite another man ; his eyes acquired a sudden brilliancy ; his countenance became animated, and his figure seemed as if inspired...... “ Monge, debilitated by age, was at last the victim of an imagination which, according as the times were adverse or pros- perous, carried him beyond either just fears or just hopes...... His last moments were without last thoughts—without last effusions—without any adieu: he sunk in silence—without agonies—without terror—and without hopes......The rules of the service did not allow the generous youths to deposit at the time of his funeral the token of their remembrance and their regret upon the tomb of their old benefactor; but on the dawn of the day after the funeral, the pupils went silently to the place of burial, and fixed upon it an oaken bough, to which they hung a crown of laurel. Twenty-three former pupils of the Polytechnic School, residing in the town of Douay, jomed together with one accord, and wrote to M. Berthollet to beg he would superimtend the erection of a monument to be built at the expense of the - former pupils of the Polytechnic School, in honour of Gaspard Monge. M. Bertrand, Notary, No. 46, Rue Coquillicre, Paris, is charged with the receipt of the subscriptions. ‘The pupils who have studied architecture are invited to propose their plans for Monge’s monument, and to send them, with an estimate, to M. Bertrand.” This notice is terminated by a list of pupils who have already subscribed. The second part contains a catalogue and analyti- cal review of Monge’s writings, not only of those which he published separately, but also of those which are inserted in the Memoirs of the Academy, or of the Polytechnic School, and in many other collections. All these works are well known, and duly appreciated ; we have extracted in preference the slighter anecdotes, those which, exhibiting as it were the mind of Monge, explain the attachment of his former pupils, and the regrets of his fellow labourers. On the Pontine Marshes; by M. De Prony. Paris, 1818.-- At the meeting of Jan. 9, 1815, the author read a memoir, in which he gave a general idea of the great problem relative to draining and rendering wholesome the Pontine Marshes. This memoir appears again at the head of this work, of which it forms the introductory part, and is accompanied with interesting notes, which could not be got into the text. In the 442d year of Rome, at the time of the construction of the Appian way, the Pontine district was in a marshy state. About 150 years afterwards, Cornelius Cethegus undertook the drainmg of it. These works were afterwards neglected until the dictatorship of Julius Cesar, whose vast projects were inter- rupted by his death. Nero, Trajan, and their successors, bestowed much attention on the Appian way, and but little on 1820.] Royal Academy of Sciences. 63 the Pontine Marshes. Theodoric confided the draining of it to Decius. Leo X. and Sextus V. caused several works worthy of notice to be executed, but these were by no means to be com- pared with the works executed from 1777 to 1796 under the pontificate of Pius VI. who expended 9,000,000 of francs upon them. Unfortunately, the plan had been laid on theoretical views, very specious, and very seducing, proper indeed in many respects, but being too general, the consequences were unfortu- nate ; so that these works considered in a hydraulic point of view exhibit mere sketches of vast conceptions, in which man parts of great importance are wanting, having been thought unworthy of notice. Very circumstantial, historical, and critical details upon all these objects are to be found in this work. By means of borers, it has been ascertained that the sea formerly washed the feet of the mountains which form the eastern and southern boundaries of the Pontine Marshes. The whole of the phenomena concur in showing that the formation of these marshes was caused, on the one hand, by brooks and torrents running into a gulph which formerly covered the isles of Circe, Zanoni, and Ponza ; and, onthe other hand, by the sea forming two ridges of sand banks, the last of which has at length shut up the communication between the sea and the internal gulph. Colmates’s method of employing currents of water charged with mud to raise up the soil by its deposition and successive increase, offers here only a secondary resource, as its effect is so very slow. Notwithstanding its insufficiency, it will be proper to continue the trials of this kind, which have been already begun. And M. de Prony advises the use of it for the amelioration of some soils, to which he believes it to be very applicable ; -but it cannot be considered as any other than a subsidiary means. The principal method to be used for the draining of these marshes can only be a good system of canals to carry off the water. To establish a system of this kind, it would be neces- sary, in the first instance, to procure an exact plan of the ground, its declivities, its torrents, its rivulets, the quantity of Tain that falls annually on it, and the quantity it throws off by evaporation. This preliminary knowledge, being at present very imperfect, M. de Prony has begun to fill up the parts that were still wanting to complete it. By means of three signals placed at known distances on the same straight line, he determined, in the most expeditious manner, all the points from whence he could observe his three signals. He has also reduced this curious problem to general and convenient formule. In fact, this is only a particular case of the problem by which Hipparchus determined the eccentricity and distances of the sun and moon. Snell was the first that transferred this problem from the heavens to the earth, and made use of it in surveying. Hipparchus’s problem has been reduced by us into general formule, which comprehend the case used by M. Prony. We have been curious 64 Proceedings of Philosophical Societies. [Jan- enough to compare the two methods; and we have found them equally exact, and equally expeditious. Thus, by uniling together the different memoirs whick have been communicated to him, along with the results of his own survey, and the observations he made during his residence in the Pontine Marshes ; as also with the levels, borings, and other works, executed, at his desire, by that skilful engineer M. Scac- cia, the author has been able to form, for his direction in the project of draining these marshes, a collection of materials much more complete than those on which the former projects had been undertaken. The recent progress of the doctrines of running water has also furnished him with means which were wanting to his predecessors. By the help of all these means, he has been able to form a plan which will satisfy all the conditions required by that celebrated problem, the draining of these marshes. The work is divided into four sections. The first contains the description and dimensions of the Pontine basin ; the second coutains the state of these marshes before tie execution of the works ordered by Pius VI. In the third, there is given a description of their present state, and an analysis of the different projects formed anterior to 1811. The fourth and last contains the author’s own views, and his projects for the ulterior benefit of the Pontine Marshes. In all of these we find a number of curious and instructive tables, in which the author has collected. all the results of his observations and calculations. It is evident that it is impossible for us to analyze them ; we shall only notice the true measure of the ancient Roman foot, deduced from the distance of the 42d and 46th milestone on the Appian way, the only ones which have not been thrown down and removed. The true Roman foot is 0:294246 metre, or 10 inches 10 lines -044 of the old Paris foot. In the fourth section, which is the most extensive, and con- tains more especiaily the application of the hydraulic theories, the evil consequences of paring and burning the soil are shown ; also the present state of the Po, which, by means of the soil it deposits at its mouth, now gains 70 meires yearly from the sea, instead of 25, which it gained yearly from the 12th to the 17th century ; the deposition of soil formed by the Tiber ; and lastly, the contrary effect produced by the sea on the shore hetween Anzo and Astura. ‘‘ The Italians are, perhaps, the first who save to modern Europe the example of moderating the descent and velocity of currents by means of falls, but they never employed sluices for any other purpose; the glory of using sluices to establish a communication between two large basins was reserved for France. The canal of Briare, which joins the Loire to the Seine, and which was finished in 1642, is the first example of the union of two rivers by a canal traversing the country lying between their two beds. This example was fol- lowed with great success by the contrivers of the canal of 1820.) Scientific Intelligence 65 Languedoc, begun in 1668, and finished in 1681. Thus the French engineers have, without the least contradiction, the exclusive glory of having invented canals, and of having pro- duced, as the first application of this invention, two grand works, justly esteemed the finest in their kind; and the novelty of which has not been sufficiently remarked or perceived by those who have written the history of the art.” The remainder of the work contains, at full length, the appli- cation of the principles and formule given by the author in his Physico-mathematical Researches upon Running Waters. These principles and methods, established upon all the experiments the author could collect, have been already reduced to practice in several cases, and especially in'a very large drainage; namely, that of the marshes of Bourgoin directed by M. Roland. The whole review of this work shows this important conse- quence—the possibility of including in regular canals all the water which inundates this unfortunate soil, and of giving it a free and easy passage tothe sea. The draining being completed by the means now pointed out, the keeping the ground in good culture will be neither difficult nor expensive, but it should be followed up with great care. The results of such extensive researches for rendering whole- some the neighbourhood of Rome, and for its prosperity, cannot be foreseen at present with much certainty: the author has done every thing that depended on him; and his work will at least exhibit to young engineers an useful example of the union of theory and experience in forming the project of an extensive drainage. (To be continued.) ArTICLE IX. SCIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS ° CONNECTED WITH SCIENCE. I, Potatoe. The general opinion is, that the potatoe is indigenous in America, and that it was brought from that continent to Europe by the Spaniards soon after the discovery of America by Colum- bus. A fact mentioned in the Transactions of the Linnean Society, vol. xii. p. 585, may, perhaps, be considered as a corro- boration of this opinion. Don Jose Pavon, of Madrid, one of the authors of the Flora Peruviana, states, in a letter to Mr. Lambert, that he and his companions Ruiz and Dombey had found the potatoe (Solanum tuberosum) growing wild in the environs of Lima, and 14 leagues from thence on the coast of Vou. XV. N°I, E 66 Scientific Intelligence. (Fan. Peru, as well as in Chili; and that it is cultivated very abundantly in those countries by the Indians, who call it Papas. Il. Remarkable Difference between the Celestial and Terrestrial ¢ Arc of the Meridian. In the year 1808, Baron von Zach determined the latitude of Florence at the Observatory of the Grand Ducal Observatory, and found it by 506 observations of different stars to be 43° 46’ 4:31’. In 1809, he determined the latitude of Pisa by 504 observations, made at the Observatory, and found it to be 48° 43’ 11:77”; so that the difference between the latitude of these two cities is 2’ 52°54”. Baron von Zach likewise ascertained the longitudes of these two places, by observations of the occultations of various stars by the moon, and found them as follows : Florence, 35’ 40-2” in time E. of the Observatory of Paris Pisa, 32. «80 In the year 1815, when Tuscany was restored to its legitimate sovereign, Ferdinand IV. the reigning Grand Duke ordered. a trigonometrical survey of the whole Grand Duchy to be made. This. survey was committed to the care of Father Inghiram, Professor of Astronomy, and Director of the two Observatories of Florence. He conducted it with the greatest possible preci- sion, as may be seen in the three following memous, which he published in succession. 1. Dalla Longitudine e Latitudine delle Citta di Pistoja, e di Prato. Estratta dal vol. delle Memorie di Scienze Matem. e Fisic. dell’ Imp. e R. Accademia Pistojese, per Anno 1816. Pistoja, 1816. 2. Della Longitudine et Latitudine Geografica della Citta di Volterra, S. Miniato e Fiesole. Firenze, i817. 3. Di una Base Trigonometrica Misurata in Toscano nell’ autunno del 1817, letta in Livorna all’ Accademia Labronica il di 7 Febrajo, 1818. Firenze, 1818. During the course of this survey, he joined Florence and Pisa together by a series of triangles, and thus was enabled to deter- mine geometrically the difference between their latitudes. Baron von Zach had determined the latitude of Pisa astronomically, * 43° 43’ 11:77” Inghirami found it ....... . 43 43 = 19-40 Difference. ...... Babb ke « ; 00 00 7:63 This enormous difference, if we were to ascribe it to the operations of Inghirami, would suppose an error of at least 100 .toises in the geodesiacal operations ; which is quite inadmissi- » dle. The longitude of Pisa, as found by the astronomical observa- tions and the trigonometrical survey, was ikewise different. 1820.] Scientific Intelligence. 67 Zach found it... 28° 2’ 0:0” E. from Ferro Inghirami...... 28 4 1-2 Difference eure ancy OU ae aoe This difference, though much greater than the former, is not 30. Surprising. _ Inghirami was much mortified at these discrepancies, which he considered as throwing a slur'upon the accuracy of his opera- tions. He, therefore, used every possible exertion to get rd of them. At first, he rested satisfied with a short base which Baron von Zach had measured durmg his observations, to deter- mine the latitude of Florence ; but he afterwards measured a much longer one himself, and went over all the parts of his calculations again and again with the most scrupulous attention ; but his efforts were unavailing: Baron von Zach considers the error to lie in the astronomical observations. He is of opinion that astronomical instruments, notwithstanding the great accu- racy with which they are now made, are not capable of giving the true latitude nearer than two or three seconds. Another cause of the difference, he thinks, may be the attraction of mountains, or of masses of matter below the surface of the earth, having a greater or smaller specific gravity than usual, which, by ‘acting on the plumb line, must occasion an error in the astronomical observations. A. third cause, he conceives to be the irregularity of the figure of the conformation of the earth.— (Correspondence Astronomique, Geographique, Hydrographique et Statistique, du Baron de Zach, vol. i. p. 1. Genoa, 1818.) III. Positions of different Places on the North Coast of Africa. Capt. William Henry Smyth, of Royal Navy, at present. employed in the Mediterranean in an astronomical, geographical, and hydrographical mission, has determined the latitudes and — of the following places on the north coast of Africa as ollows : Longitude East from Ferro, Tripoli (house of the British Consul)/32° 54’ 13730° 50’ 30” North Jatitude. Leptis magna (tent inthe ruins). ..|832 37 23 31 47 15 Gherrza (at the tombs). .......... 30: 37. 30,31 48 30 Cyniphus (river, mouth of)........ 32. .33 25 (31,54 20 Asal Amrah (the point) .......... 82. 61). 5 acl BOp oA Benhouleat (the castle) ........... 31..28..10.30: 58 0 Cape Bon (the tower) ..........6- 37. .4. 45 28 43.45 Pantellaria island (the castle). ....29 35 5 36 51 15 Tajoura (the point) .............- 32. 63°. .Q. adidiil) Galita island (the centre) ........-37. 32 30 26 84 50° (tbid. p. 68.) 68 Scientific Intelligence. [Jan. ‘IV. Position of different Places in Sicily and the Neighbourhood, determined by Capt. W. H. Smyth. Longitude East North latitude. from Ferro. Messina (the fanal) ........ sajeanad 38° 11’ 30%33° 14” 557 Syracuse (the fanal) . ........000. BL... 2.,.00.1b2 590. BO Milazzo (the fanal, Cape Bianco). ../88 15 45 82 54 15 Raape St, VitOs ojs:eince aia ict ala eee aye 38 10 50/30 26 0 Cape de Gallo (Bay of Palermo) ...38 14 1031 1 30 Ustica Isle (Fort Falconara)....... 38 43 40 30 51 45 Stromboli Isle (church of St.Bartolo)38 48 0 |82 52 55 Lipari Isle (castle). .........+...-/88 28 35 [82 35 25 Felicuri Isle (church) ............ 38 34 15 32 5 55 Maritimo Isle (castle) ...........- 38 1 10/29 48 40 (Ibid.) V. Positions of different Places on the North Coast of Africa, determined by Don Dionysio Alcala Galiano. The best chart of the Mediterranean, which has yet appeared, was published by the Spaniards, in the year 1804, under the following title : ‘‘ Carta esferica que comprehende las costas de Italia, las del Mar Adriatico, des de Cabo Venere hasta las islas Sapiencie en la Morea, y las correspondientes de Africa, parte de las islas de Concega, y Cerdena, con las demas que compre- hende este mar ec. Corregida la costa de Africa y las islas de Sicilia, de Lipari y Sapiencie en 1804, por las observationes ec. por D. Dionysio Alcala Galiano ec.” The latitudes and longitudes in that chart correspond well with those given by Captain Smyth. Hence there is every reason to trust in the precision of the following places on the northern coast of Africa, taken from Galiano’s chart: Longitude East North latitude. fram’Fore. Isola Piana. ...... Stare eter by arch ot ven OF. t PAGO B92) Stray Cupe. Blanca... Dr. b 0c. SPovec a. ..37. 17 0 (27. 40-30 istes of Dogs..v es. fii... owe id a'eies 37 18 0 |27 56 30 Citse Benin, Oh. ects kee aa oe oe 37) Ter -OlQBie'4on3o Porto Wartaee Ch. .24: Pee es Pl 36 52 028 9 30 Golettade Vans: + 02:22 285705 te 36 48 380 28 5 30 Mes d’Iimbres. Gs. POG: bee hacaus: 37.2..7 (O28 BRS dale Limpione 2). 0008s etesie 35 35 0 30 10 30) Sele Bimpsa se. oe ek Se etete .. 05. 50". 30: (80. 58.30 1820.] Scientific Intelligence. 69 The following positions of places on the coast of Sicily are likewise taken from the same chart : Longitude East from Ferro. —_——<$<$$<—$$<$<<— ——— aaa nied North latitude. BIE AUDD. .0:0ca o.5:p xevsle-s esrevereere ws ilBB°-33/ 3071382..267..07 Torre del Faro ........-- we at aaa 38 15 30/33 21 30 Agosta ..... Salseais tid. 5 saa iain ate © sae af, 17° 30 Cap de Morro ....ceeeeeeeees WAGE... Siscc Cap di Passaro. ......00006. ...(36 39 30 Cap Scaramic .......eeeeeeees ..36 46 30 Punta della Sacta........-0e0-0- 37 51 30 (83 27 00 (Ibid. p. 73.) VI. Position of various Places in the Mediterranean by Mr. Rumker. North latitude. Long. East from) Variation of Greenwich. |the compass. BMAP. Code Stas sikla's\ ~ ofale o/s 39° 36’ 30”119° 32’ 15” S. Vito, near Corfu...... 3937 °25 6: Maura...'..... & As et 38 40 00/20 35 00 Bele GileWaea <6 .%s\- 38 12 0020 35 00 Port Chieri, in Zante....|37 46 00 |20 55 15 SVFACUSCs: stan sce = 0's DA pti Ml i ad Wak = Aa BS Isle Maritimo .......... Bee’ SoG: IS ee OO Lo. Isle Gorgonna.......... 48 26 00/10 9 00119 Cagliari, in Sardinia..... 39 12 00 Isle Cabrera, below Ma- ete UE a ae eo? 39 7 OO} 1 40 15 Isle Alboran (Africa)....135 56 00;3 1 O Gibraltar (European point)/36 8 OOS? 10: W (Ibid.p. 76.) VII. Position of La Valetta, in Malta. Baron von Zach has fixed the latitude and longitude of this place as follows, from the observations of Father Feuillé : North latitude, 35° 54’ 30” East longitude, 32 5 53 from Ferro, or 48’ 23:5” in time east of Paris.—(Ibid. p. 83.) 70 Scientific Intelligence. : (Jan. VIII. Geographical Positions of several Places in France, Swit- - zerland, and Germany. , Longitude| Height E. of|Frenck Paris. |feet. Longitude E., Places. Latitude. from Ferro. Strasburgt.......s+ce+-eeee -|48° 34 57°60'"|25° 25’ 16:46//)21’ 41-1”) 448°5 Donon... -..e.seceseccsveee-|48. 30 48°34 124 50 6:25 |19 20°4.|3108°6 Bressoir 02.0.2 ecee Pop Boe 48 11 25°20 |24 49 13°86 |19 16:9 |3789°5 Balon ....... seacececccvece (47, 54 » 5:39 | 24 -46 . 789119 © 4-5 14401-3 Bolchenberg ...... sleseeese-|4% 49 23°52 |25 30 12-66.)22: , 0 8149566 Colmar...... o cde gefer'e s oom (480 4 APO 195. IV 42°33 120... 63 Oberberghen)? Term of the|47 57 44°85 |25 4 18-63 |20 17-3 | 632°5 Saursheim : base. 47 AT 29:02 }25 3 29:09 |20 13:9'| 720°7 SROOE YANN; potato oie viatelo=(oleiaiemiale AT 15 30°81 |25 11 54:79 |20 47°6 |1399°6 Cliasseral.... 12... eee ee ences AT § 0°87 |24 43 46°98 |18 55:1 |4960°6 SeRNeS sca ok.cs enh ele’ a= weeee-/46 56 51°91 125 T 18:39 [20 29°2 116463 Walperswyl 2 Term of the|A7 3 23°69 |24 54 17°57 |19 37°2 |1377°3 Sugy. ...... ‘ base. 46 57 46°57 |24 48+ 2°54'|/19 12°2 11347-1 Lichtenberg, ........0+0-0e-- AS 55. .19°50 |}25 9 27°95 |20 37-9 |1278'5 Rastadt .......20200. 000-02: AS 51 29-23 |25 52 26-83 |23 29°8 | 506-4 SONEMICONGS ces sepsis See eel 49 1 4324/25 33 25:02 |22 13-7 |1559:9 “ACHENSDETE. OTe occ ee wn vere « 49. 5 20:24 /26 13 56°90 |24 55:8 | 796-1 NEES eo eins scree rier airinniee 49 19 12°39 |25 45 13°51 |23 0:9 |2077:0 Mannheim, Observat........ .-|49 29 15°13 |26 T 5I-T2 124. 31°5 | 302°3 Mont-Tonnere. ........++-- ..|49 87 25°86 |25 36 10°30 |22 24-7 |2090-0 BECTUEES Vas cee o's «9s e's o.---|49° St 19°32)/25. 9 3°18 )20 36°3 1736-0 Melibocus.....sscscevees ods 49 43° 32°82 /26 18 27°64 |25 13-8 |1677°4 Merstein.....-.---e-eees ..--{49 52 45°92 1/25 59 52°88 |23 59-5 Darmstadt (Base) .......-.-.- 49 52 20:94 /26 19 39°34 |25 186 | 4488 Nierstein .....ceeecceneees ..[49 51 39°53 |26 13 16-40 |24 53:1 | 594°5 Frankfort, s. Ms... ..-.--- »-150 6 A2-49-126 21 23°28 125 25:5 The above table is published in the Correspondence Astrono- mique, Geographique, Hydrographique et Statistique, of Baron von Zach, vol. i. p. 149. The positions were ascertained by geographical engineers, of the Bureau Topographique at Paris, some of them nearly 20 years ago, but the results had not been published before. Baron von Zach considers it as exceedingly correct. : IX. Latitude of the Observatory at Manheim. Prof. Schumacher, at Copenhagen, from a great number of observations, has determined the latitude.of the Observatory at Manheim to be 49° 29’ 13-70’.—(See Zach’s Corr. Astron. i. 193.) : X. Height of the Passage over the Splugen. The Austrian engineers at present employed in making this road have determined the height trigonometrically, and found it 6393 French feet above the level of the sea. Dr. Schouw, one of the philosophers at present travelling at the expense of the King of Denmark, found the height, by a barometrical observa- tion, 6451 French feet. The difference between these two determinations is only 58 feet, which, in the case of an isolated | 1829.] Scientific Intelligence. 71 barometrical observation, may be considered very small. For- merly the height was reckoned only 5926 French feet. This is the height given in the Almanack of Gotha.—(Ibid. p. 197.) XI. Further Observations on the Double Rainbow seen at Paisley. By Mr. Macome. (To Dr. Themson.) DEAR SIR, Paisley, Nov. 16, 1819. The kindness with which you gratified me with a solution of such difficulties in chemistry as opposed my attempts to acquire some knowledge of that fascinating science, induced me to trouble you with a notice of a singular rainbow I had lately witnessed, and in which the more refrangible colouring rays were distinctly repeated—an appearance which I could not account for. As the statement, however, was drawn up without the most distant view towards publication, I perceive it is not sufficiently explicit in detailing the principal attendant circum- stance—a knowledge of which may probably lead to an explana- tion of the phenomenon. While viewing a rainbow of the usual appearance, a driving shower from the south-west was moving in a direction which would cross obliquely a line uniting me with the southern limb of the arch. When the shower approached this line, the back ground, on which that beautiful paimting of nature was delineated, darkened exceedingly, and exhibited a quadrant, the most brillant I. had ever beheld, with the follow- ing number and arrangement of the colours : red, orange, yellow, green, blue, violet, green, blue,and violet. It was the arrangement of the last three mentioned colours that puzzled me ; forhad the order been reversed, I should have been disposed to refer their production to a partially reflected image of the usual spectrum. But this was by no means the case, nor did any fainter shade of colour- ing indicate an origin different from that of their less equivocal neighbours. The encroachments of the advancing shower left me little opportunity of further observation, only an impression remained on my mind that the breadth of the whole spectrum was not proportional to what might have been expected from the great refrangibility of the rays which formed this novel addi- tion to it. lam, dear Sir, your obedient servant, A. Macome. XII. On Rain-Gauges. By Mv. Holt. (To Dr. Thomson.) DEAR SIR, « Cork, Oct. 9, 1819. Inthe Transactions of the Wemerian Natural History Society for December, 1815, Mr. Kerr laid before the Society a model and description of a new rain-gauge, constructed on the principles which seem to have actuated M. Flaugergues to assert in the 8th volume of the Bibliotheque Universelle (and thence trans- 72 Scientific Intelligence. PJan. lated into the Annals of Philosophy for August), that it was not difficult to account for the difference in the quantities of rain that fall imto rain-gauges placed at different heights. Your correspondent Mr. Meickle, in the Annals of Philosophy for September, objects to the theory of Mr. Kerr and M. Flan. gergues as unphilosophical ; and endeavours, by a mathematical diagram, to show that, be the inclination of the rain what it may, the same quantity of drops will be received by the rain-gauge. It appears to me Mr. Meickle has taken a wrong view of the subject. I shall endeavour to express my ideas in as few words as possible. If the receiving surface of the rain-gauge be dis- posed parallel to. the horizon, it may be readily shown that should the rain fall perpendicularly, it will receive its due propor- tion ; but it may also be as readily shown that if the rain be driven by a current so as to fallin an angle more or less inclined to the horizon, the same quantity of rain can never enter the gauge. Should the rain be blown in a direction parallel to the horizon, it is obvious none could enter: if the inclination be at 10°, the quantity received will be less thanif the angle were 20°; much less than at 30°; and so on: so that the quantity received will be always in proportion to the angle of inclination. The -annexed diagram will illustrate the subject. Let a, 6, c, d, represent the vertical section of the common rain-gauge ; a c or b d perpendicular to the hori- zon. Ifthe rain be inclined at 45°, as at e a, f c, the quantity which can enter through a 6 will be as the rectangle con- tained by eg, perpendicular to -e a or f c, and the side a 6, which rectangle is equal to about seven-tenths of the square of .ab. If the inclination equal 20°, as at ha, ik, the quantity received will be as the rectangle under / m and a 6; equal to about one-third of the square of a 6. If the inclination be 60°, as at x a, op, the receiving superficies will be equal to the rectangle under x g and a.d, about a of the square of a 6. Thus it is evident that in no inclination can so great a quantity of rain enter as when it falls perpendicularly. Perhaps the phenomenon of more rain being collected in a low contined situation than in an exposed high one may be explained thus: a current of wind, impinging the flat side a bc d. of the gauge, would be glanced round the edges ac and 6 d, and also over the top a b, it would, therefore, sweep off a consi- derable portion of the falling rain, and thereby induce a false estimate ; the same cause operating in a much less degree ina tow or confined situation would necessarily occasion the com 1820.] Scientific Intelligence. 73 monly observed results. Should we adopt the gauge recom- mended by Mr. Kerr, it would be necessary to construct a scale of the surface at every degree of the rain’s inclination, as it will be observed that the maximum of surface will be when. the rain inclines in an angle of 45°, and the minimum when either hori- zontal or vertical. If the gauge were shaped like a funnel, it would in a great degree prevent the effect of height or exposure, or the quantity of rain collected, because the impinging current would be inclined to the smaller end of the cone; and little, if any, would be disposed to pass over the top. I have the honour to be, dear Sir, Your most obedient humble servant, Tuomas Hott. XU. Further Remarks on propelling Vessels by Windmill Sails. By Mr. Bartlett. (To Dr. Thomson.) SIR, Buckingham, Nov. 1, 1819. Permit me to point out the following errata which appear ina note (pp. 859, 360, of your number for the present month) to my paper On the Propulsion of Vessels by Means of Windmill Sails, which you did me the honour of copying into your Annals. They arise from the incorrect manner in which the decimals are pointed off, viz. 4,021,248 square feet should be 4021°248 ; 670,208 x 32 = 21,446,656 lbs. 670208 x 32 = 21446-656 ; and 128,679,936 lbs. 128679-936; the three right hand figures of each quantity being decimal fractions. The note was thus erroneously printed in the work which you extracted it from; but, as the product of those numbers was correct, I did not think it necessary to notice the mistake, until copied into your pages. You remark that the idea itself “ is not new,” it having been « proposed nearly a century ago ; ” in reply to which, | beg to observe, that it can certainly lay but little claim to originality ; being nothing more than the application of one power to the mechanical impulsion of another ; in other words, imparting momenta to the machinery of steam-vessels by means of wind- mill sails. But, if lam not mistaken, you allude to the plan of Bishop Wilkins for impelling land carriages, which | conceive, both in its construction and application, to be widely different from the one I propose. I did not know, until long after I had submitted my ideas upon the subject to the world in a separate treatise (which afterwards appeared in the Pamphleteer), that such a suggestion had been made as to the possibility of moving carriages on wheels by means of revolving sails ; and I have yet to learn that it had ever been proposed so to impel Aoating bodies. ) The idea first suggested itself to me upon witnessing the 74 Scientific Intelligence. [JAN. construction of a mill worked by the two powers (i. e. steam and» wind); and had not the present mode of navigation by the former force been so widely diffused, it is more than probable that it never would have occurred to me. I have the honour to be, Sir, your very obedient servant, J. M. Barrier. XIV. Galvanic Experiment. (To Dr, Thomson.) SIR, Glasgow, Oct. 9, 1819, The other evening, when reclining on my pillow in a chamber where on all sides darkness was distinctly visible, and while rubbing my eyes, an employment by the by in which the hands of the indolent are frequently engaged, [ happened accidentally to thrust my thumb below the superciliary ridge, at the same time raising the upper eye-lid a little, and was somewhat asto- nished to perceive a fine semicircle of light, which was perma- nanent as long as | kept my thumb in the above position. To ensure success, the room must be dark, and the nail of the thumb must be towards the eye, and press considerably on tiie upper eye-lid while in the act of raising it. This luminous appearance [f ascribe to galvanic agency, but probably it may be owing to some other cause. However, if the experiment is actually new, and worthy ofnotice, you may insert it in your magazine ; if not, you will pardon me for mentioning such a trifle, and excuse the ignorance and presumption of Your most obedient humble servant, W.R. *,* Though the preceding fact is not new, I have inserted this notice of it for the sake of many readers who may not be much conversant with physiological investigations.—T. XV. Singular Substance found ine Coal Tar Apparatus, By Mr. Garden. In one of the condensing vessels of an apparatus erected for the distillation of coal tar, and for the purpose of exposing various bodies to the action of that substance at a boiling heat, there was found a considerable quantity of a concrete matter which had distilled over with the volatile oil. The substance m the state in which I received it was mingled with a portion of darkly coloured tar oil, from which by repose it subsided in the form of a granular-like crystalline mass; when the oil was poured off, and the remaining portion separated as much as possible by passing the solid matter between several folds of blotting paper, it was digested in alcohol slightly heated ; in this way nearly the whole was dissolved.. The solution upon coolig deposited an abundance of crystals of a tabular shape, still coloured by a small quantity of adhering oily matter ; by repeated solutions and 1820.] Scientific Intelligence. 75 crystallizations, it was obtained in the form of brilliant white scaly crystals; similar to benzoic acid, but of a more silvery lustre. This crystallized. substance exhibited the followimg characters : Its smell was peculiarly pungent and somewhat aromatic, unlike that of any substance with which I am acquainted. Fusible at a temperature of 184°, and completely volatilizable at that, and even lower temperatures. Insoluble in water. Soluble in essential and in expressed oils. Readily soluble in alcohol, from which it was again separated by the addition of water. Fuming nitrous acid assisted by a gentle heat exerted a con- siderable action upon it, first changing it into a brown-coloured viscid oil, which dissolved, and upon cooling, a group of minute stelliform crystals were formed, not unlike camphoric acid. Acetic acid, when gently heated, readily dissolved the sub- stance, but let it fall again upon cooling. Alkaline solutions did not appear to have any remarkable action upon it. Its solution in alcohol neither changed the colour of litmus or of turmeric paper. From the preceding statement, it would appear that this substance bears a strong analogy to camphor in many of its characters. Camphor is soluble in acetic acid both warm and cold, and remains in permanent solution; but this substance, when dissolved in the same acid, separates from it in the form of crystals, when the solution is suffered to cool. A more minute investigation than that which I have yet had an opportunity of instituting would be necessary to determine the true nature of this body. Whether it be campher in disguise, or something else, it certainly coincides in some of its habitudes with the concrete essential oils. 372, Oxford-street, Dec. 18, 1819. A. GARDEN. XVI. Death of Dr. Rutherford. On the of Dec. died Daniel Rutherford, M.D. Professor of Botany in the University of Edinburgh. Dr. Rutherford was the discoverer of azote, which was first described by him in his Thesis De Aere Mephitico, published in 1772. 76 Col. Beaufoy’s Astronomical, Magnetical, [JANn. ARTICLE X. : Astronomical, Magnetical, and Meteorological Observations. By Col. Beaufoy, F.R.S. Bushey Heath, near Stanmore. Latitude 51° 37/42 North. Longitude West in time 1’ 20:7”. Astronomical Observations. Nov. 6, Emersion of Jupiter’s first § 6 20’ 27’ Mean Time at Bushey. satellite .........0--eee06- 0 6 21 48 Mean Time at Greenwich. Magnetical Observations, 1819. — Variation West. mien Morning Observ. Noon Observ. Evening Observ. onth, Hour. | Variation. | Hour. Variation. Hour, | Variation. Noy. 1 8h 35/} 24° 32’ 07 1h 35’| 24° 40! 14” 3 2) “8 Sa) 947 Age) aI SS at tS Es 3} 8 30/24 31 48 1 35 | 24 38 35 s 4| 8 35] 24 30 58 1 20] 24 41 00 e 5] 8 30] 24 32 25 I 25 | 24 40 18 2 6| 8 30/| 24 32 37 1 20] 24 42 05 s T| 8 30/24 30 45 1 25 | 24 37 55 a 8} 8 30} 24 33 GO| 1 25} 24 39 26 s 9\ 8 35/24 31. 38 1 25] 24 38 40 = 10; 8 35 | 24 33 30 1 15 | 24 38 31 o dl 8 30 | 24 32 46 1 15] 24 39 32 2 12} 8 35 | 24 31 45 1 15 | 24 40 26 i 13} 8 35 | 24 33 47 1 15.) 24: 40 32 a 14| 8 35] 24 44 50 1 20) 24 39 51 g. 975| 8 35 | 94 34 45 1 20/24 38 43 % 16] 8 45/24 31 42 1 20 | 24 38 26 o 17} 8 35 | 24 33 00 1 20}; 24 38 34 = 18} 8 35/924 32 11 1 20} 24 38 40 ss 49) 8 35 ):24 31 39/— —|— — — rs 20} 8 35] 24 31 37 1 20| 24 38 16 i 2) 8 30/24 31 32 1 20 | 24 36 09 ° 22} 8 35/24 381° 33 { 20 | 24 38 33 a 23) 8 35/94 31 54] 1 20/24 35 36] & 24; 8° 40/ 24 32 39 1 20 | 24 38 25 = 25) S$ 40! 24 38 48 1 20 | 24 39 O62 = 26| 8 40)| 24 33 55 1 20); 24 37 19 & 27; 8 40 | 24 33 34 1 15 | 24 36 32 a QS S.A el SAE ISD AMS | eae re = GY ew eencnl| ceeds p ames, yt inSS These yess ot pec ee ee 30] 8 35 | 24 34 09] 1 20) 24 35 31} += Sc Mean for the 8&8 35} 24 32 42 1 21] 24 38 43 Month, In taking the mean of the morning observations, that of the 14th is rejected, being so much in excess, for which there was no apparent cause. On the noon of the 2Ist, the needle vibrated at intervals 15, and in the evening it rained and snowed. and Meteorological Observations, Meteorological Observations. 77 Time. | Barom. | Ther. | Hyg. | Wind. Velocity. Weather. Six’. — oe — EE 2, Nov. Inches Morn....| 29-400 449 | 830 ENE Rain 43° ] Noon....| 29-332 45 7 ENE Cloudy 46 Even — _ — _— _ } 39 Morn,...| 29°258 Al 83 | N by W Very fine 2 2|Noon — — — —_ —_— 46 Even....| — _ — _ _ bss Morn....| 29-413 36 719 WNW Clear 3¢ |Noon....| 29-500 | 44 62 INW by W Clear AAY Even.. — _ — — — b 4: Morn....| 29-485 | 41 | 77 |SWby W Cloudy + 4¢ |Noon....| 29-460 | 40 67 | W by N Cloudy 50 Even... _ _— — —_— _ Al Morn....| 29-248 46 73 SW Cloudy 5< |Noon....} 29°158 51 71 |SWby W Cloudy 51k Even....| — _ — — —_ 432 Morn....| 29:035 | 44 86 SW Fine 2 64 |Noon....| 29:002 | 50 64 SW _ |Cloudy 50% Even —_ _ —_ _ _ 38 Morn....| 28°942 AO 76 Wsw Clear ‘ 74 |Noon....| 28-983 | 48 65 WNW Showery| 48% Even.. ~ == _— = — 35 Morn,...| 29°110 | 37 19 | NEbyN Very finel 84 |Noon..../ 29-110 | 41 70 NNE Fine AQz- Even... _ = _ — - 30 Morn....| 29:402 | 32 73 w Very ‘nel 94 |Noon..,..) 29°368 | 41 62 Ww Cloudy AAR Even... _ = _ _ _ 372 Morn....| 28:870 | 44 83 WwW Foggy ‘ 2 104 |Noon....| 28°850 | 48 10 | WbyN Fine 49 Even....| — _ —_— — — b 423 Morn....| 29°129 A4 84 NE Rain 114 |Noon....| 29233 | 44 18 NE Rain 44s Even....| — _ _ — _ : 35 Morn... -| 29°500 38 19 NNE Fine 124 |Noon....] 29:480 | 45 } 73 NE Rain | 452 Even....) — —_ — — _ ¢ 40 Morn....| 29°347 Al 13 NE Showery 1s} Noon....| 29°323 | 44 | 66 NE Cloudy | 45 Even _ — — — _ 40 Morn....| 29°325 | 40 85 NNW Sm. rain 144 Noon....| 29°323 | 44 | 74 Var. Cloudy | 44 Even — — i a —< 40 Morn....] 29°312 Al 83 WbyS Fog asf Noon....| 29256 | 45 | 78 ssw Cloudy | 45% Even... _ _ = _ _ 38% Morn,...| 29°063 39 86 NNW Rain ‘ 164 Noon....| 29:000 | 39 } 79 NNW Cloudy | 40 Even — _ _ — — SA1 Morn....| 29°160 | 39 87 | NEby E Showery ‘ E) nr} Noon....| 29:300 | 41 | 85 | NEby E Rain ALR Even....) — _ —_ _ — 31 Morn....| 29°600 38 15 ENE Fine ‘ sf Noon....| 29°600 AO 62 ENE Very fine} 43 Even....| — _ _ — = ee | Wi.) Col. Beaufoy’s Meteorological Observations. (Jan. Meteorological Observations continued. Month. | Time. | Barom.} Ther.| Hyg. | Wind. |Velocity,|Weather.|Six’s. : Inches, Feet. t Poe pate a es a) 52 NE Fine 284 | are ek ee — .|. 358 *""] 29-230 | 31 | 69 | Wbys Cloudy : 303 1. .| 29-066 | 34 | 68 sw Cloudy | 404 12] e8-628. | 35 | 84 | WNW Fine ; me ‘| 98-664 | 40 | 74 NW Cloudy | 405 ‘2 9-018 | 32. | 76 | WNW Very finel a8 "'| 29-038 | 35 | 68 NW Clear 464. ""!| 99-270 | 29 | 72 | Weby N Clear bong ".1!| 99-978 | 35 | 67 | WNW Fine 35 “""| 99-403 | 28 | 76 NW Clear bos .| 29°442 37 70 NW Clear 38% “""| 99-546,| 30 | 77 | NNW Clear b 29 se..| 29°504 | 38 val SW Very fine| 38 "| e990 | 33 | 85 | NNW. | Sleet t 30 “*"] 99-993 | 36-| 80 NW Foggy ||, 362 """| 9-495 | 33 | 83 NW Snow ; ig ‘| 99-498 | 37 | 17 | Why N Fog 31k "*""] e9-393 | 30 | 83 SSE Foggy t so | 29-300 31 | 82 SSW Foggy | 46 Morn....| 99°112°| “46 | 97 ssw tain, tor) ¢ 4° Noon....| 29°135 50 94 SSW | Rain, fog) 51 {IT 29-220 | 49 | 94 SSW Rain # as Noon...., 29°135 | 54 87 SSW Showery 502 -+| _— et —— — | _ Rain, by the pluviameter, between noon the Ist of Novem- ber, and noon the Ist of December, 1:761 mech. The quantity that fell on the roof of my Observatory, during the same period, 4892 inch. Evaporation, between noon the Ist of November and noon the Ist of December, 1:230 inch. 1820.] 1819. Mr. Howard’s Meteorological Table. ArTIcLE XI. METEOROLOGICAL TABLE. ae Max.} Min. ee ee —_— 1ith Mo. Nov. 2 3 4, 5 6S W/)29°64)29°44 7 8 9 JIN E/29°86/29'80 IN W/29°93|29'81 N W/30-04|29:93 W_ |29°93|29°84 S W\{29'84!29°64 W |29°65/29°45 N W129:92/29°65 N W({29-92\29°38 NN W([29°65/29°38 N.. E/30-01\29-65 12N /30-00\29'94 ISN = E/29°94/29'89 14, N_ |29°89/29-88 15) W_ |29°88!29°65 16'N W|29°69)29°65 7, E |30°16|29-69 17 18.N E 30:16)/30:07 19,N E)30°07|29°84 20'N Wheg's4 2018 1.N W/)29°62/29-18 IN W)29:85)\29°62 23,N W/29°90'29:85 24.N W'30:07'29:96 25|N Wi30°07'29°S81 26\N W 29:97 29°81 27,\N W 29:97 29°82 28/5 W29:97\29:74 29'S W 29°75)2974 30S W29°81/29°75 | | Max. 48 49 46 54 55 | — | | BAROMETER.| THERMOMETER, | Min. _50°16'29:18| 55 | 21 Lvap. |Rain. 02 No) i) Gr eld tlibtida tela Etdd Dp © ea) 17 Os 0 22) elf aE IAase ie 79 — thn (OAS AOS The observations in each line of the table apply to a period of twenty-fous hours, beginning at 9 A, M. on the day indicated in the first column, A dash denotes, that the result is included in the next following observation. 80 Mr. Howard’s Meteorological Journat. [Jan. 1820. REMARKS, Eleventh Month.—1. Overcast. 2. Cirrus, Cirrocumulus, Cirrostratus. 3. Fine. 4, Cloudy: lunarhalo. 5, Overcast: lunar halo. 6. Cirrus, Cirrocumulus : lunar halo. 7. Cloudy: rain. 8. Fine: Cirrus. 9. Fine: a swallow seen this morn- ing, 10. Rain. 11. Gloomy: drizzling. 12, 13. Cloudy. 14, 15, Gloomy. 16, Rainy. 17. Drizzling. 18, 19. Cloudy. 20. Fine day: rainy evening. 21. Overcast: windy, 22. Fine. 23, 24. Hoar frost in the mornings : misty. 25, Foggy day: lunar halo. 26. The roads and footpaths coated with ice: cloudy: snow at night. 27. Misty: much rime on the trees: some snow early this morning. 28. Hoar frost: misty: rain at night. 29. Very moist air: a condensation on the outside of the windows: rain, with wind, 30. Rain. RESULTS, Winds: N,1; NE,6; E,1; SW,5; W,3; NW,14. Barometer: Mean height For the month, .....,0..scceececsecceccceccesees 29°S01 inches. For the lunar period, ending the 8th. ..........-.. 29°837 For 15 days, ending the 13th (moon north) ...... 29°781 For 13 days, ending the 26th (moon south) ....... 29°823 Thermometer: Mean height For the month, .......scccecereccecccceecececeess 39BIO For the lunar period (as above) ....2+++-+eee+ «++ A4A4 For 30 days, the sun in Scorpio.....-+seeeeeeeeee- ADE] Hygrometer: Mean for the month . ....scseccccacceccrecccseees SS BIVAPONACLON: Sich os.b c's stay caida ie tton < senile ais eeetieladcelee ectie’s wnat k Wo peel. brea letersta seine ele eisleib'c sic ciccistel gp eaaclesiuetis's Speieistssisejes/cetiqjen ss «ete NAH Pets OTLGOUEAM Jora'a.s ae a+ oinieeite\os aisledelsine sicieeiani=saiecisies s e/eesuenile Stratford, Twelfth Month, 20, 1819. L. HOWARD. —~e— Large Meteor, Tottenham, Eleventh Month, 18.—At about 10 minutes past five, p.m. a brilliant meteor appeared in the west; it was first seen descending from the zenith, at an angle of 45°, with a slow and steady motion towards the north, It showed much larger than the planet Venus when at full, exhibiting a body of yellow flame rather drawn out behind, and burning quietly without sparks. ‘When the combustion ceased, there remained a matter faintly luminous, which gradually became extinct as it passed below the westernmost stars of Ursa Major.. The twilight was pretty strong in the south-west at the time. Preiernatural Vegetation.—Some of the horse chesnut trees on our green (at Tottenham) have this year exhibited a pretty complete double vegetation. The trees in question are rather unhealthy, and probably stand in a bed of dry gravelly soil; the others in loam, Towards the decline of the summer, after having flowered abundantly and perfected the fruit, they shed their leaves, which had been spoiled by the drought and dust. Immediately on feeling the effect of the rains about the autumnal equinox, they put forth leaves and blossoms a second time, exhibiting for several weeks a very singular and pleasing contrast to the now mature and brownish foliage of the more healthy individuals of the same species. The new fruit set pretty well even on the branches on which the old remained, and was as Jarge asa pea; when the premature approach of winter, shortening the duration of the autumnal season, notwithstanding the protracted summer had delayed its arrival, brought down both new and old, with the foliage remaining on the respect ive trees, together, L, He ANNALS OF PHILOSOPHY. me a a re me as | FEBRUARY, 1820. ArTIcLe I, On Arsemc. By Thomas Thomson, M.D. F.R.S. IN a short article on arsenic inserted in vol. xiv. of the Annals of Philosophy, p. 466, I showed that the result of the most careful experiments hitherto made gave the composition of the two acids of arsenic as follows: Arsenious acid........+++ 4:75 arsenic + 1-5 oxygen Persona ered. 2". 2) ee 75 + 2:5 or, if we consider an atom of arsenic to weigh 9:5, the compo- sition of these acids may be stated as follows : Arsenious acid ...........+. 9°5 arsenic + 3 oxygen mrsemie wend ATs lott 9°5 +5 According to this last notion, arsenious acid is a compound of 1 atom arsenic + 3 atoms oxygen, and arsenic acid of 1 atom arsenic + 5 atoms oxygen. The weight of an atomor integrant article of arsenious acid will be 12-5, and of arsenic acid, 14:5. his mode of viewing the subject has the advantage of getting rid of the fractional parts of oxygen, which make their appear- ance when an atom of arsenic is reckoned to weigh 4-74, as I have done inthe last edition of my System of Chemistry, and indeed, as has been hitherto done by every chemical writer whose works I have had an opportunity of seeing. The best way of determinmg whether 14:5 or 7:25 be the number which represents the weight of an integral particle of arsenic acid seems to be a careful analysis of the arseniates. Unfortunately the greater number of these salts being insoluble Vou. XV. N° II. F 82 Dr. Thomson on Arsenic. [Fres. in water, we have not the means of obtaining them in regular crystals, the only method in our power of preventing mechanical mixtures from being substituted for chemical compounds. There are, however, two arseniates which can be procured in regular crystals with great ease; namely, arseniate of potash and arsenate of soda. The first of these has been long known to chemists by the name of Macquer’s arsenical salt. But I have not hitherto met with an accurate account of the arseniate of soda in chemical books. [I shall, therefore, take the opportunity of describing it here. I. Arseniate of Soda. To form this salt, I took a considerable quantity of arsenic acid, which I had made by boiling nitromuriatic acid on arse- nious acid till the whole was dissolved, and then distilling off the nitromuriatic acid. Into this acid I dropped solution of carbon- ate of soda till all effervescence was at an end, and till the liquid ceased to redden litmus paper. The mixture was now evapor- ated to the requisite consistency on a sand-bath, and set aside for crystallization. But though the weather was peculiarly favourable, not a single crystal could be obtained. The liquid rendered cudbear paper violet, and gave other unequivalent symptoms of containing an excess of alkali. Arsenic acid was, therefore, dropped into it till all effervescence ceased. The liquid, which now reddened litmus paper, being set aside, yielded abundance of crystals of arseniate of soda, and by repeated evaporations, I succeeded in extracting the whole of the salt in tolerably regular crystals to the very last drop. All the crystals thus obtained possessed the very same properties ; therefore, though the liquid reddened litmus paper, it contained no uncombined arsenic acid. By dissolving the arseniate of soda thus formed in hot water, and setting it aside in a cool place, I obtained it in large regular transparent crystals, consisting of rhomboidal prisms, the faces of which were inclined to each other at angles of 64° and 116°. The bases of these prisms were rhombs, which, as far as I could make out, had likewise angles of 64° and 116°. These crystals remained unchanged though exposed to the open air for a week in my laboratory ; but when I carried them into my library, they speedily effloresced on the surface, and became white and opaque; but did not lose their form or fall to powder after a month’s exposure. The taste is cooling, and bears some resemblance to carbonate of soda, but is not so strong. It is very singular that though the liquid from which these crystals were deposited reddened litmus paper, the crystals themselves render cudbear paper strongly purple, and even perceptibly affect litmus paper rendered ved by acetic acid. Now these effects are usually produced by ukaline bodies. 3 1820.] Dr. Thomson on Arsenic. 83 The specific gravity of these crystals is 1759, that of water being reckoned 1-000. Now if the salt be a compound of 1 atom arsenic acid, 1 atom soda, and 20 atoms water, as we shall im- mediately find reason to conclude its constituents to be, the mean specific gravity of such a compound (supposing no condensation) would be 1078. Hence it appears that the 22 volumes of which it consists are condensed into about two-thirds of their original- vulk One hundred grains of water at the temperature of 45° dissolve 10-132 gr. of this salt after being deprived of its water of crys- tallization. Now this is equivalent to 22-268 gr. of the crystal- lized salt. The specific gravity of this liquid (containing very nearly =',th of its weight of the dry salt) at the temperature of 60° is 1:0903. Now the specific gravity of such a solution, supposing no condensation to have taken place, would have been 1:0698. Thus there is a condensation which scarcely exceeds two per cent. The salt is much more soluble in water of the temperature of 60°, and when the temperature amounts to 120°, the liquid dissolves more than its own weight of the crys- tallized salt. This salt does not dissolve in alcohol; but when a crystal of it is suspended in that liquid, its surface is deprived of its water of crystallization, which renders it opaque and white. When heated, it speedily undergoes the watery fusion, the water of crystallization being more than sufficient to keep it in solution at a boiling temperature. When kept for some time in a temperature of between 500° and 600°, it loses the whole of its water of crystallization, and is corwerted into a white powder. When this powder is exposed to a red heat, it undergoes the igneous fusion, and becomes liquid and transparent like water. By this treatment it sustains an additional loss of weight; but this loss is partly at the expense of the acid of the salt, which seems to undergo a partial decomposition ; for the salt after this treatment is no longer completely soluble in water. The greater number of the arseniates are insoluble in water. Hence the arseniate of soda occasions a precipitate when dropped into most of the earthy or metallic salts. The following table will put the reader in possession of the colour, solubility in nitric acid, &c. of the most remarkable of these precipitates. Effect produced by dropping a saturated Solution of Arseniate of Soda at 45° into various saline Solutions. 1. Muriate of Barytes.—Becomes slowly milky, and a white precipitate falls. Redissolved by nitric acid. 2. Muriate of Lime.—A white precipitate. Redissolved by nitric acid. 3. Nitrate of Strontian.—A white precipitate. Redissolved by nitric acid. F 2 es Dr. Thomson on Arsenic. [Fer. . Muriate of Magnesia.—No change at first ; but on heating vd mixture, a copious white i fell. 5. Muriate of Alumina. ai Vhite precipitates. | Redissolved 5 Alum. by nitric acid. . Nitrate of Lead.—A white precipitate. Redissolved by ee acid. 8. Sulphate of Nickel.—An apple-green precipitate. Redis- solved by nitric acid. 9. Sulphate of Cobalt.—A dirty-red precipitate. Redissolved by nitric acid. 10. Nitrate of Silver.—A flesh-red precipitate. Redissolved by nitric acid. 11. Muriate of Tin—A white precipitate. Redissolved by nitric acid. 12. Pernitrate of Mercury.—A white precipitate. Redis- soly = by nitric acid. 13. Protosulphate ‘of Iron——A_ greenish-white — precipitate. Redissolved by nitric acid. 14. Sulphate of Copper.—A bluish-green precipitate. Redis- solved by nitric acid. 15. Sulphate of Zinc—A white precipitate. Redissolved by nitric acid. 16. Sulphate of Manganese-—A white precipitate. Redis- solved by sulphuric acid. 17. Muriate ef Iridium.—No immediate change; but on heating the liquid, a brown precipitate fell. 18. Sodamuriate of Rhodium.—No immediate change ; but on heating the liquid, a yellowish-white precipitate fell. 19. Nitromuriate ‘of Platinum.—A light-brown precipitate. Redissolved by nitric acid. 20. Nitromuriate of Gold—No ERIE © change ; but on heating the liquid, a yellowish-white precipitate fell. 21, Muriate of Antimony y.—A white precipitate. Redissolved By ee acid. . Tartar Emetic.—No change. 33, Hydrosulphuret of Soda- and-Antimon, y. Nochange. {t now only remains to determine the composition of this salt. { attempted in vain to determine in what proportion the acid and base unite by saturating the acid with the alkali, or vice versé, noting the quantities of Peach employed. I could not determine when I had reached the requisite point of saturation, as the liquid still continues to act upon vegetable colours when that point has been reached. For tunately, the analytical method in the present case is attended with little difficulty. Fifty grains of the crystals, by cautious exposure to a heat slowly raised to 550°, lost 27-25 er. of their weight, which-I consider as the water ‘of crystallization of the salt. When the same weight of salt is exposed to a red heat, it sustains a loss of 1820.] Dr. Thomson on Arsenic. 85 weight amounting to 29 gr.; but this cannot be allowing to the loss of water, for the residual salt is no longer completely soluble in water. The most accurate experiments which I have been able to make give 28°31 of water in 50 of salt, or 56°62 in 100 of salt. : Fifty grains of the salt were dissolved in water, and precipi- tated by nitrate of lead. The precipitate being washed, dried, and heated to redness, weighed 49:8 gr. Now from the analysis of arseniate of lead by Berzelius compared with my own experi- ments upon the same salt, I consider it as established that it is a compound of According to this statement, 49:8 gr. of arseniate of lead contain 17 gr. of arsenic acid; therefore, arseniate of soda must be a compound of Arsenic acid. .o:..0e00-.+ L700 or 34:00 SORA. ates a een 2 tent + BAGO 9°38 Water ee Wes oe oee Sk 56°62 50:00 100-00 Now the weight of an integrant particle of soda is 4, and we have 4°69 : 17 :: 4: 14-5; so that the weight of acid in this salt bears to that of the base the proportion of 14°5to4. Therefore, if we consider this salt as a compound of an atom of acid and an atom of soda, the weight of an atom of arsenic acid will be 14:5. Il. Arseniate of Potash. This salt has been long known, but has never been accurately described. It was first formed by Macquer, who obtained it by distilling in a retort a mixture of equal parts of nitre and arse- mous acid.* This salt usually crystallizes in four-sided rectan- gular prisms terminated by very short four-sided pyramids. IL have some very fine crystals of it obtained by spontaneous crystallization. They are nearly three inches long, and of a proportional thickness. In them the prisms gradually diminish in size till they terminate in a point; so that the crystals have the appearance of consisting of enormously long octahedrons. This salt has a saline and cooling taste, somewhat similar to that of nitre. It is not in the least altered by exposure to the air. Its specific gravity is 2-638, and it has a much firmer and more solid texture than the crystals of arseniate of soda, indicating obviously from its appearance that it contains much less water of crystallization. 1t may be kept in a heat of 550° for a consi- derable time without melting or undergoing any remarkable * Mem, Par, 1764, p, 223. 86 Dr. Thomson on Arsenic. [Fes. change. The portions of the salt next the vessel, however, ~ become whiter a little, and probably lose part of their water of crystallization, though the salt loses no sensible weight. In a red heat, it melts, and becomes as liquid as water. In that state it is nearly colourless, having only a slight tinge of yellow, and sometimes of green, both of which shades disappear when the salt becomes cool. On concreting, it cracks in all directions, indicating that it occupies a smaller bulk when solid than when liquid. ‘The congealed salt is opaque, or only translucent, and white: 100 gr. of the salt by this treatment lose 7-5 gr. of their weight. The salt is completely soluble in water ; therefore, the 7°5 gr. may be reckoned the water of crystallization. Arseniate of potash is insoluble in alcohol: 100 parts of water at the temperature of 42° dissolve 19-047 gr. of the salt. The specific gravity of this solution (at 60°) is 1:1134, It is much more soluble in hot than in cold water. Hence a saturated solution in hot water crystallizes very readily on cooling. The constituents of this salt, according to my analysis of it, are as follows: ATSEMIG BOIG. sib i6iss cctaehe wis 65:426 Potashss2<.%% 4 aielalie nee tats 27-074 IW caticietpenenercuaticloilbe ereherscersves cnt OOO 100-000 Now the weight of an integrant particle of potash is 6, and 27:074 : 65:426 :: 6 : 14:5 very nearly. As far, therefore, as this salt is concerned, the weight of an atom of arsenic acid may be 14:5. ( If you mix together a solution of arsenic acid and soda in the proportion of 7:25 arsenic acid + 4 soda, the liquid acts like an alkali upon vegetable blues, and cannot be made to vield crys- tals. We have, therefore, no accurate means of determining whether the acid and alkali form a salt in these proportions or not. The same observation applies to a mixture of 7°25 arsenic acid with six parts of potash. IJ. Arsentate of Copper. No fewer than five varieties of this salt all crystallized, but varying in the colour and shape of the crystals, have been described by Count Bournon, and analyzed by Chenevix. Unfor- tunately the analysis was made at a time (1801) when the necessity of minute accuracy was not so much felt as at present. Hence we are not to expect exact agreement between the atomic theory and the analytical results of Mr. Chenevix. Four of these five varieties occur crystallized in the copper mine of Huel Garland, in Cornwall. The fifth variety was formed artificially by Mr. Chenevix. He poured arseniate of ammonia into nitrate of copper, and filtered the liquid to get rid of a green-coloured 1820.] Dr. Thomson. on Arsenic. 87 precipitate which fell. The liquid was now concentrated by evaporation, and a quantity of alcohol poured into it. A preci- pitate fell consisting of rhomboidal crystals of a blue colour. Chenevix found the constituents of this salt as follows : PCH veleie = ot wh me seiny sed . 14:50 Black oxide of copper. .... 12°83 Water: os oe es sees Scie Boe 8-82 Now the number which represents the weight of an integrant particle of black oxide of copper is 10. I think, therefore, that it isnot unlikely (if we suppose an atom of arsenic acid to weigh 14:5) that this salt is a compound of 1 atom of arsenic acid = 14-5 + | atom of black oxide of copper = 10 + 8 atoms of water = 9; so that this arseniate rather favours the opinion that an atom of arsenic acid weighs 14-5. The second of Mr. Chenevix’s varieties of arseniate of copper occurs in thin hexahedral plates, has a fine emerald green colour, and a specific gravity of 2°548. Its constituents were found to be: AYSeNIC ACID... eee cece .. 14:50 Black oxide of copper...... 13°50 I oa wD aon Bie De bs daw sip eke 6:07 This (reckoning the weight of the atoms as before) is a com- pound of 1 atom acid + 1+ oxide + 6 atoms water, making PETA 8 ia aah & natAa eae 7 ee 14°50 COSINE... cists ae pacid’s dé» vy SaaS i RY ares iit 6°75 The third and fourth varieties of Chenevix obviously agree in their composition ; or if there be any difference, it consists in the water. They agree in colour (green) and in specific gravity, viz. 4280. How far the crystalline forms can be reconciled remains still to be determined. The constituents of these two varieties, according to the analysis of Chenevix, are as follows: - First Variety. Second Variety. BRET sy sha Aiea vlan, cigs aSi Se ices vetoes SEE RIG rye) 0's ss me En “as wahsi ining sett PVater sss sia +6 esistp ie TL «oi osysipun ie rad oe They obviously consist each of 1 atom of acid united to 24 atoms of oxide; while the first contains 9 atoms of water = 10-125, and the second, 7 atoms water = 7-805. Mr. Chenevix’s first variety occurs crystallized in obtuse octa- hedrons. Its colour varies from blue to green, and its specific gravity is 2:881. Its constituents, according to Mr. Chenevix’s analysis, are as follows : Acid. *eeteeveseeoeveoseeoeeoneee 14:5 OTEE SE SS A RR go 50:0 Water. seeceeeoererer eves eovoee a7 88 Dr. Thomson on Arsenic. [Fes. This is obviously equivalent to 1 atom of acid = 145+4 6 atoms oxide = 50 + 52 atoms water = 36. We see from the preceding statement that the composition of these salts is not inconsistent with the notion that the weight of an atom of arsenic acid is 14:5; but a new analysis of them would be desirable. Want of the requisite specimens prevents me from having it in my power to undertake it, IV. Arsenate of Iron. There occur in the copper mines of Cornwall small cubic crystals of a dark-green colour, which Mr. Chenevix recognised to be an arseniate of iron usually contaminated with a portion of copper. This salt (abstracting the impurities) he found com- posed as follows : Arsenic acid.: ...2cscecree.s 14°50 Protoxide of iron.......... 20°91 Water tse oa 4, Melek nee Now an integrant particle of protoxide of iron weighs 4:5. I conceive, therefore, that the salt in question is a compound of 1 atom arsenic acid = 14-5 + 5 atoms of protoxide of iron = 22°5 + 4 atoms water = 4°5. This salt then is not mcon- sistent with the notion that an atom of arsenic acid weighs 14-5. V. Arseniate of Lead. Beautiful specimens of this salt occur in Huel Unity mine, near Redruth, in Cornwall. It has a wax-yellow colour, and is crystallized in large six-sided prisms. Mr. Gregor, who analyzed these crystals, found their constituents (abstracting a smal] quantity of muriate of lead) as follows : AISERIG BEIT zee neces aed es 4c 14°5 Protoxide of lead, ic. i243... 36° Now this is equivalent to 1 atom acid = 14°5 + 2+ atoms protoxide of lead = 35 (for an atom of protoxide of lead weighs 14). The composition of this salt then is not inconsistent with the notion that an atom of arsenic acid weighs 14-5. There is an arseniate of lead which precipitates in a white powder, when arseniate of soda is dropped into nitrate of lead, This powder is a compound of e Arsenic acid Ay A tee a Siam pede Protoxide of lead......-... 14:00 But it is not inconsistent with the notion that an atom of arsenic acid weighs ]4°5. We have only to consider the salt as a subbinarseniate or a compound of | atom acid + 2 atoms oxide of lead. Thus I have gone over all the crystallized arseniates with which I am acquiinted, except the arseniate of ammonia, without 1820.] Dr. Thomson on Arsenic. 89 finding the composition of any of them inconsistent with the notion that an atom of arsenic weighs 14:5. I have not yet satisfied myself sufficiently respecting the constitution of the two varieties of arseniate of ammonia which are known to exist. But from the experiments which I have made, I may venture to say, that they will not be found to militate against the number 14:5 as the equivalent for arsenic acid. Upon the whole then the present state of our knowledge seems to make the choice of that number preferable to 7°25, its half, which | adopted m the fifth edition of my System of Chemistry. it has the advantage of destroying the fractional parts of oxygen, which, on the suppo- sition that 7°25 is the weight of an atom of arsenic, enter into the composition of arsenious and arsenic acid. We may, there- fore, fix upon the following numbers as representing the weight and composition of arsenic, arsenious and arsenic acid : M Arsenic, weight of its atom, 9-5. Arsenious acid composed of 1 atom arsenic + 3 atoms oxygen = 12°5 weight. Arsenic acid composed of | atom arsenic + 5 atoms oxygen = 14-5 weight. ArTIcLe II. Experiments to determine the Composition of different inorganic Bodies which serve asa Basis to the Calculations relative to the Theory of Chemical Proportions.* By J. Berzelius. {In a memoir published several years ago, I stated some experiments by which I endeavoured to obtain results sufficiently exact to serve for data, by means of which the composition of various compounds might be calculated with more certainty than they could be determined by analysis itself. As in these expe- riments I employed methods, such that the results depended as little as possible on the dexterity of the experimenter, I enter- tained some hopes of attaining my object; but | met with so many difficulties inseparable from that enterprize that none of my results could be considered as normal. After six years of continual experiments on this subject, and after having acquired much experience and having discovered several improvements in the analytical methods, | resolved upon resuming these researches, which | consider as of the greatest importance. My object has been not to obtain results which are absolutely exact, which | consider as only to be obtained by accident, but to approach as near accuracy as chemical analysis * Translated from Afhandlingar i Fysik, &c. y, 379, 90 Berzelius’s Experiments to determine the Composition [FEx. can go, and to give an equal degree of precision to the analyses of the most important bodies. If by these efforts the inevitable errors in the results become proportional, even though they are not absolutely correct, they will be of the same utility to us as if they were so, because the mistakes are all within the limit of our observation, and as nearly as possible proportional for all combi- nations. In endeavouring to determine to what degree of accuracy it was possible to arrive, I have found that by very simple methods it was possible to come within one-thousandth part of the weight employed ; so that variations in the results of experiments made by the same process differ only from each other in the ten-thou- sandth parts ; but even this degree of accuracy requires much care and attention in all the circumstances which may contribute to render the results accurate, and which usually vary with the manner of operating. I have never been able, except accident- ally, to make the results coincide beyond the ten-thousandth part, and indeed very frequently, notwithstanding all my care, they have not agreed perfectly beyond the hundredth part. Some of the experiments, which | intend to relate, were made with the views just stated. Others are of an older date, and have been already related in the third volume of the Annals of Philosophy by Dr. Thomson. But among these last several have been repeated, and some mistakes in my original memoir have been corrected. I shall first give a description of the experi- ments in which I endeavoured to obtain the greatest possible precision ; I shall then state those whose accuracy I cannot gua- rantee to the same degree. ' Experiments to determine the exact Composition of the Bodies, which in a great Number of Analyses serve as Bases to the Caleulations of Chemical Proportions. Muriate of Potash and Muriate of Silver.—Of all the methods to determine the exact quantity in potash and in the oxide of silver, none seems to me more likely to be exact than to deter- mine in the first place the quantity of oxygen in the oxymuriate of potash, and afterwards to analyze the common muriate. By experiments already known, it has been established that oxymu- riate of potash exposed to ared heat loses ten times the quantity of oxygen contained in the potash of the residual muriate. If we determine accurately the quantity of oxygen disengaged from the oxymuriate, and then calculate, by the way just stated, the quan- tity of oxygen which the potash should retain, the error resulting will amount only to 1th of the error of observation in the analysis of the oxymuriate. It is long since I published an analysis of the oxymuriate of potash by which I had found that 100 parts of that salt give out 38°845 parts of oxygen; but to reach a greater degree of preci- sion I considered it as requisite to repeat the experiment. In 1820.] of different inorganic Bodies. 91 my new researches, a difficulty presented itself which I was not aware of in my former ones, and which laid me under the neces- sity of making in the first place a great number of experiments in order to find a method of operating which should always give the same results. The difficulty consists in this, that just when the oxymuriate begins to be decomposed, the oxygen carries along with it a portion of oxymuriate in the form of a white smoke, and deposits it in the tubes. This smoke is deposited so slowly that when I passed the oxygen through a glass tube two feet in length, curved in different directions, and drawn out at the end so as to form a tube almost capillary, the last half of the tube was not covered with dust; but a piece of glass against which I allowed the jet of gas to strike became entirely covered with it at the place where the gas struck it. As the formation of this saline powder seemed to be merely the mechanical effect of the boiling (for it increased with this last), | endeavoured to avoid boiling by mixing it with from six to ten times its weight of fused muriate of potash. By this method | gained my object, and I then proceeded in the following manner: Oxymuriate of potash, the solution of which was not at all rendered muddy by nitrate of silver, was reduced to a fine powder, and dried in a temperature higher than 212°, but not sufficiently so to soften the salt. It was then put while hot into a retort which contained muriate of potash in powder. It had been heated to disengage all moisture, and its weight was known. When the mixture had recovered the temperature of the atmosphere, the retort was weighed again. It was then shaken to mix the two salts. By means of a caoutchouc tube, a glass tube 16 inches long, and a line in diameter, was attached to the retort. Into this tube some pieces of dry muriate of lime had been put. It was curved into a spiral, and the opening surrounded by filtering paper to retain all the saline smoke in powder. Care was taken to weigh the tube both alone and in connexion with the retort. The quan- tity of oxymuriate decomposed varied from 15 to 10 grammes. The retort was heated in a sand-bath till it became red within, and till the muriate began to soften. When the experiment was finished, the oxygen gas within the retort was changed for atmo- spheric air. The retort was then weighed along with the tube, and finally the tube alone. In all these experiments, a trace of sublimate was found in the beak of the retort. It was oxymuriate undecomposed. It weighed in all 0-003 gr. The tube with the pieces of muriate of lime and paper had increased in weight from 0-02 to 0-023 gr. By subtracting this quantity of weight from what the retort had lost, we obtained the quantity of oxygen disengaged, and at the same time that of the muriate of potash remaining in the retort, Four experiments were made in this manner, and taking into the account the small quantity of sublimate, 100 parts of the oxymu- nate gave 92 Berzelius’s Experiments to determine the Composition [FEB.- In the first.......... 39°146 of oxygen gas BeCUIN tases OO Low Clird ei ee ine) oO LOOr fourteen eae Teg These experiments vary only in the ten-thousandth parts, and two of them even agree in them. We may, therefore, consider it as exceedingly near the truth that 1UU parts of oxymuniate of potash, when pure and dry, give out 39°15 parts of oxygen yas. To be able to make use of this result, it is necessary to know the exact composition of muriate of potash. I took, therefore, muriate obtained by these experiments, in which the best reagents could not detect the least excess of alkali, and 1 decom- posed it by a solution of crystallized nitrate ofsilver : 10 grammes of muriate of potash gave in two experiments 19°24 grammes of fused muriate of silver; but it was necessary to know with the same degree of precision how much muriate of silver is obtained from a given weight of silver. Different chemists have made experiments on the subject, but the results do not always agree with each other. Those who have come nearest the truth I consider as the following. Wenzel found that 100 silver gave 131-4 of muriate of silver; Davy, 1525; Bucholz, Rose, Marcet, and Gay-Lussac, 133°3; and finaily, in my former experiments already described, I found from 132-7 to 132°75 ; for the degree of accuracy requisite in experiments which are to serve as a basis to our calculations, the difference between 132°5 and 133°5 is too much. Even the difference between 152-7 and 152-75 has a very sensible influence on the results deduced from it. It was, therefore, necessary to examine if the results of my old experi- ments were exact ; and in that case which of the two was nearer the truth, 1. I dissolved silver purified with the requisite care in pure nitric acid in an inclined phial, and the liquid was evaporated to dryness in the phial to get rid of all excess of acid. The nitrate of silver was then dissolved in water, and the clear solution was poured into ‘a solution of sal-ammoniac. The precipitate was collected on a filter, well washed, dried, and then fused upon a watch glass of a known weight. A current of sulphuretted hydrogen gas was then passed through the filtered liquid, but no trace of silver could be discovered. ‘Twenty grammes of silver gave in this way 26°54 grammes of muriate of silver; that is to say, 100 of metal gave 132:7 of munate, This experiment can only err by a loss, since any excess of weight is impossible. 2. To compare this result with that of an experiment in which no loss could be sustained, and in which consequently the error must be in excess, [ dissolved pure silver in an inclined phial, evaporated the solution to dryness, redissolved the nitrate,in water, and added to it in the same phial pure mumiatic ) ~ 1820.] of different inorganic Bodies. 9% acid* as long as any precipitate fell. I immediately evaporated it to dryness, and as towards the end the two acids destroy each other, so that a little nitrate of silver might be again formed, I poured water on the dry mass, added mumiatic acid, and evapo- rated the whole to dryness a second time. The phial with its contents was then exposed to a spirit of wine lamp till the muriate of silver was entirely melted : 20 grammes of silver treated in this manner gave in two experiments 26°550 and 26-558 grammes of fused muriate of silver, equivalent to 132-78 and 132-79 of muriate from 100 of silver. Though the acids employed in these experiments were as pure as they can be obtained by the best known methods of preparing them, they always left visible traces, when evaporated, on a watch-glass. But, as in these experiments, it had been neces- sary to add these acids in considerable quantities, it is obvious that the small quantity of foreign matter which they contained must have acted on the balance, and rendered the weight a little greater than it would have otherwise been. As the true point must lie between 152-7 and 132-79, I think we may adopt 132:75 as suficiently near the truth, observing always that the uncertainty in the results exists only in the ten-thousandth parts, which constitute the ordinary limit beyond which I have not been able to carry analytical experiments. Admitting that 100 of oxymuriate of potash give 39-15 of oxygen ; that 100 of muriate of potash give 192-4 of muriate of silver; and that 100 of silver give 132°75 of muriate of silver ; we may conclude from these three data by a calculation too simple to render it necessary to give an account of it here, the composition of the following bodies: Muriate of potash is composed of Muriatic acid. .... 36°743 ...... 100-000 TOUR! S ctutasslordec's DOE Od okbam tel Ze seo Potash is composed of Potassium. ...... 83°0484 ...... 100-000 SEO, cin 5 bois, 6) 4 POE 6a e's, atau SAS Oxide of silver is composed of RIVER). wiaieisciae oe 90° 112)... 6 +.100-0000 WIEDEN. 2 sieinieidis oO B8Ry) 4, sad). T3986 Muriate of silver is composed of Muriatic acid .... 19:0966 ...... 100-000 Oxide of silver. .. 80°9034 ...... 423°652 The capacity of saturation of muriatic acid, that is to say, the * This acid had been prepared by saturating water with muriatic acid gas, which had passed through an intermediate yessel to deposit all impurity. 94 Berzelius’s Experiments to determine the Composition [Fxrs. quantity of oxygen which must exist in the base capable of satu- rating 100 of the acid, is then 29°184, instead of 29-454 as Lhad found it in my former experiments. It is equally evident that these data are sufficient for calculating the composition of muriatic acid, oxymuriatic acid, and oxymuriate of potash. But I pass by these calculations in silence as they are foreign to the object which I have in view. Oxide of Lead. It is of very great importance to know accurately the compo- sition of the oxide of lead, especially in consequence of its great influence in the analysis of organic bodies. Although in my former and numerous experiments on this oxide, I obtained results which agreed with each other, I thought it necessary to repeat them, in order, if possible, to bring them to a greater degree of precision. 1. Composition of Oxide of Lead found by direct Analysts. — Among the analytical methods which depend the least upon the dexterity of the operator, I conceive that the following occupies the first rank. Ina glass globe blown in the middle of a piece of barometer tube, a quantity of oxide of lead was troduced which had just been exposed to a red heat. The glass ball was now heated by a spirit lamp, and a current of hydrogen gas pre- pared from distilled zinc, and sulphuric or mumiatic acid was passed through it. The oxide becomes at first black, small globules of reduced lead are seen, and after an interval of two hours, it is converted into melted lead. The lamp is withdrawn, and the lead is allowed to cool, while the hydrogen gas still con- tinues to pass. If we weigh in the first place the tube of glass alone, then when it contains the oxide of lead, and lastly when it contains the reduced lead, the only possible error must proceed from inaccuracy in weighing, provided we have employed a hydrogen gas absolutely free from sulphur. I made in this way three experiments: (1.) 21:9425 grammes of oxide of lead left 20-3695 grammes _ of metallic lead ; that is to say, that 100 lead had been united with 7°72235 oxygen. (2.) 10°8645 gr. of oxide of lead yielded 10-084 gr. of lead. Equivalent to 1U0 lead united to 7°74 oxygen. (3.) 11:159 gr. of oxide of lead yielded 10°359 gr. of lead. Equivalent to 100 lead united to 7°7228 oxygen. 2. Composition of Oatde of Lead determimed by a Calculation which has for its Basis the Analysis of Niirate of Lead.—From an analytical experiment on nitrate of lead, 100 of the nitrate yield 67°31 of oxide of lead; but we know that nitric acid is composed of | volume of azotic gas and 21 yolumes of oxygen gas, and that (neglecting the oxygen probably contained in the azote) this acid ‘contains five times as much oxygen as the base by which it is neutralized. If we determine the composition of 1820.] of different inorganic Bodies. 95 the acid by weight from the specific gravity of the gases, and then calculate from the preceding data the composition of oxide of lead, we find that 100 lead must unite to 7-7448 oxygen. 3. The same calculated from the Muriate of Lead.—Fused muriate of lead was pounded, weighed, and dissolved in boiling water. It left a small portion of submuriate undissolved, which was separated, dried, weighed, and subtracted from the weight of the muriate employed. This precaution is indispensable. I have never been able to dissolve fused muriate of lead without its leaving an insoluble residue of submuriate. I have even fused it in a retort filled with muriatic acid gas without being able to prevent a partial decomposition: 100 of muriate of lead precipi- tated by nitrate of silver produced 103-35 of muriate of silver. Muniate of lead, therefore, is composed of Muriatic acid ...... 19°74 ...... 100-000 Oxide of lead ...... 80°26 ...... 406°585 It follows that 100 lead combine with 7-7316 oxygen. 4. The same calculated from the Carbonate of Lead.—I prepared the carbonate employed in these experiments by precipitating a solution of nitrate of lead by méans of carbonate of soda obtained by the calcination of tartrate of soda, or by carbonate of ammonia, both added in excess, and by washing the precipitate with pure water. The carbonate of lead was strongly dried in a heat some degrees above 212°. It was decomposed in a glass retort exactly weighed, and the gas was passed through a tube filled with muriate of lime, and exactly weighed. ‘The carbonic acid gas disengaged in two experiments had a stronger smell than usual resembling oleum cornucervt, when the carbonate of fead had been precipitated by carbonate of ammonia. This cir- cumstance induced me to sublime a portion of sal-ammoniac a second time to prepare carbonate of ammonia by distilling it with carbonate of petash ; but this precaution was unavailing. I had the same odour and the same result in weight ; and we see from what follows, that the substance which communicated the odour had no appreciable weight. The analysis gave: Precipitated by car- Precipitated by car- bonate of soda. bonatie ofammonia, Carbonic acid........... a nee NOMA AD oP 6447 Oxide of lead ...::........- BaiadS fae cee $3°333 Moisture stopped by the mu- BNE OE IMIS a0 2 4 sk balsh ORD Bt ae 0-220 The results of these experiments vary only in the sixth’figure, and may, therefore, be considered as very-‘near the truth. It follows trom them that 100 of carbonic acid are neutralized by 506823 of oxide of lead. According to the specific gravities of oxygen and carbonic acid gases, as determined by Arago and Biot, carbonic acid contains 72-623 per cent. of oxygen. We 96 Berzelius’s Experiments to determine the Composition [Frx. know that the base which saturates that acid contains half of that quantity of oxygen. The following is a comparison of the Saad of oxygen which we have found combined with 100 of ead : -7218 carbonate of lead. 7223 reduction by hydrogen. 7228 ditto. 7316 muriate of lead. 7400 reduction by hydrogen. 7-7448 nitrate of lead. We see then that 100 lead combine with more than 7°72 oxy- gen, and with less than 7:75. Three of these numbers differ only in the sixth figure, and two only in the seventh. All circum- stances considered, I conceive Cae admit as the medium of the determinations which are entitled to the greatest confidence 7°725, as the true quantity of oxygen which can unite with 100 lead. On that supposition, oxide of lead is composed of Lead gh WPT ee OS S28, et ROO Oxygen (Oia. 7171 Ree AE Sulphuric Acid. It is known that in the neutral sulphates, the sulphuric acid eontains three times as much oxygen as the base by which it is neutralized. We have just determined the composition of oxide of lead. From this it is easy to determine the composition of sulphuric acid by observing how much lead is yielded by a given weight of sulphate,of lead. I dissolved lead in pure nitric acid in a Florence flask, inclined in such a manner that the efferves- cence could drive nothing out of the vessel. The hquid was then poured into a platinum crucible of a known weight. Pure dilute sulphuric acid was mixed with it. It was evaporated to dryness, and the excess of sulphuric acid was driven off by exposing it to a red heat. This experiment appears very simple, but it is of very difficult execution, in consequence of the weight of the precipitate, which occasions portions of it to be driven out of the vessel if the temperature be raised a little above 212°. 1 made four experiments, and employed 10 grammes of lead each time. They furnished the following results : First. ........ 14:6380 of sulphate of lead. 7 7° 7: 7 7° Second. ...... 146400 hind. cies eure de, LA504A.0 Fourth’. . 5 23: 14-6458 Among these experiments, the first differs in the fourth figure ; but the others ditier only in the sixth. I conceive that 1 ma choose the result of the third experiment ; that is to say, 14-644, as nearest the truth. In this quantity of sulphate there is 10-7725 of oxide of lead and 3°8715 of sulphuric acid, the 4820.) ~ of different inorganic Bodies. 97 oxygen of which ought to be 0°7725 + 3 x 2:3175, and the sulphur, 1-5540. Of consequence, sulphuric acid is composed of PANNE sf aay ambi tes AD 1B95 silane oar 100-00 Oxygen oir. 5-13 «tle HO BOUDIs A. 36.) 148-44 Hence it follows that the capacity of saturation of sulphuric 59-8605 = 19-9535. It is known by old experiments that sulphur in order to pro- duce sulphurous acid must combine with two-thirds of the oxygen which exists in sulphuric acid. Hence it is easy to cal- culate the composition of sulphurous acid. I thought, however, that a verification of this calculation furnished by the determina- tion of the specific gravity of sulphurous acid would not be superfluous. And though the experiments which I made with this view have not given the result which I expected, I shalt here give an account of them. If we suppose that oxygen gas when it unites with sulphur to produce sulphurous acid preserves its volume just as when it forms carbonic acid gas with carbon, it is evident that the differ— ence between the specific gravity of sulphurous acid and oxygen gas ought to indicate the quantity of sulphur contained in the former gas. I prepared sulphurous acid gas in the following manner: I put copper into a retort, which I then filled com— pletely with concentrated sulphuric acid. The beak of the retort was then introduced into sulphuric acid, and the retort was heated till the gas extricated ceased to drive out sulphuric acid. The beak of the retort was then plunged under a glass jar filled with mercury, and the disengagement of sulphurous acid gas was continued. The glass vessel had at its top a stop-cock of brass, which could: not be filled with mercury, and in which there remained of consequence a little atmospherical air. This portion was removed by filling a sixth part of the vessel with sulphurous acid gas, and then throwing out this mixture of gas and air. This operation was repeated five or six times before the vessel was finally filled with sulphurous acid gas. This gas was then introduced till the gas within the glass was compressed ty a column of mercury, an inch in height, on the outside of the vessel. Ithen adapted to it, by means of a stop-cock furnished with a screw, a thin glass matrass, which | had previously exhausted of air. On opening the stop-cock, the matrass was filled with sulphurous acid gas, and care was taken to plunge the glass in the mercury till the gas in the matrass was somewhat compressed. It was then carried to the place where it was to be weighed. It was left there an hour in order to acquire the . temperature of the place, whicb. was 59°. The stop-cock was then opened, taking care not to touch the matrass with the hand, im order not to alter the temperature. The gas being thus brought into equilibrium with the air, the stop-cock was shut, Vou, XV. Nell. G acid ought to be ‘4 98 Composition of inorganic Bodies. [Fes. and the matrass weighed. The barometer varied during the experiment between 24:6 and 24°7. { continued these experiments for three days, making three each day. The weight of the sulpharous acid varied from 1-308 to 1:311, without it being possible to ascmbe this variation to changes in the pressure of the atmosphere. The quantity of air which the air-pump extracted from the matrass weighed 0-576 to 0°578 gramme; but when the air was allowed ‘to enter through a tube filled with muriate of lime, it always weighed 0:583 gramme. At each experiment, the matrass was weighed after being exhausted, to be sure that the air-pump had always extracted the same quantity of aa. The stop-cock was examined each day by leaving the exhausted matrass for half an hour on the balance without its weight increasing by the entrance of air. The errors of observation in this experiment ought always to have a tendency to give the specific gravity of the gas too small, in consequence of a mixture of air with the sulphurous acid gas. Only a single circumstance could contribute to increase the weight. The grease upon the stop-cock might have absorbed a small quantity of sulphurous acid. To determine this point, I weighed the stop-cock before and after each experiment ; but its weight was not altered. It is possible likewise that a little sulphuric acid might evaporate, and remain suspended in the gas; but I always left the gas a long time standing on the mercury before putting it into the matrass ; so that the vapour, supposing it to exist, had all the time necessary to be deposited. if we admit 1-31 as the weight of the sulphurous acid gas in the preceding experiments, 58°3 : 131 :: 1-00: 2:247. Ifin these 2-247 parts of sulphurous acid there is an equal volume of oxy- en whose weight is 1-10359, 100 parts of sulphur are combined with 96°52 parts of oxygen instead of 98-954, as follows from the analysis of sulphuric acid. This deviation is too great to be merely an error of observation. Hitherto all circumstances speak in favour of the results drawn from the analysis of sulphuric acid, which agree so well with the experiments on the composi- tion of the sulphurets, and which agree exactly with the analyses of other saline combinations, as we shall immediately see. I have not been able to find the cause of this anomaly. Some chemists pretend that oxygen gas, when it unites with sulphur, diminishes in volume, This diminution has been supposed to go as far as ;;th. But whether it is owing to a small quantity of hydrogen in the sulphur, or constitutes an exception to what we consider as a general law, remains to be determined. (To be continued.) 1820.] Demonstration of Taylor’s Theorem, &c. 99 Articie IIT. Demonstration of Dr. Taylor’s Theorem, with Examples. By Mr. James Adams. (To Dr. Thomson.) SIR, Stonehouse, near Plymouth, Dec. 22, 1819. Suoutp you consider the following demonstration of Dr. Taylor’s theorem, together with the accompanying examples, likely to benefit the young algebraist, your inserting them in the Annals of’ Philosophy will much oblige, Your humble servant, JamMeEs ADAMS, Prop. 1.—If 9 represent a function composed of known and unknown quantities, then will ‘ n/n —1)(n— (n—1) ,,4 2) o = 9 +Ao+ — — Aro + “~—-"—— Avg + Ke. From the nature of increments @ =.....9 ; , @ +Ag=o P.=t =O +Ag’ —e+AgtAgt A*paot2Ag+A°oag” 9,=9," =a"! +A” =9+3AG+4+3A°d+A ¢=9'” $,=0 =9"+A9”’=04+4A564+6A'9+4 A' 9+ Ato It is evident that the coefficients of 9, Ag, A? ¢, A® ¢, &e. are the same as the coefficients of the corresponding powers of a binomial; and, therefore, each in general is represented by —1) n(n—1) (n—2 Es 'K, le ated Rd a ierhet &c. Hence the value of ¢,, as stated in the proposition. TNE 23 Prop. 2.—To find the nth increment of the function ¢. n ; n—1) n(n—1 =—S A = %, =. NO, 1 4 of wate Poi *F ne ag PBC Prop. 3.—If ¢ represent a function composed of known and unknown quantities, then will __ do d? » d3 d3 » at Mie at He al ee By prop.1, ¢,=ndg + ae De ¢ + 2), a O54 mek d°¢ + &c. Now since the increments d 9, d? 9, a ¢, &c. are always considered as “ indefinitely or incomparably small,” let G 2 + &e. 100 Mr. Adams’s Demonstration [Fes. ° them be expressed by the fractions “, = = Then. by substi- tuting in the last equation, we shall havea, = ¢+nAg=¢@ n n(n —1) n (n— 1) (n — Q) kits, 7. %) ee a Ke. By cancelling the function ¢ and dividing by x, we get aaa ya (n—2) esa) Ne 2) ee Ag=- 4 Rete Br eS ae eee se4 oy" Now since the numerators and denominators of the fractions in the last equation increase together, the former being finite whole numbers, and the latter tndefinitely, or incomparably great whole numbers ; no sensible change will be made in the equation, by supposing each of the numerators equal to unity, according 5 . 1 1 1 to which, and restoring the values of =, —, -—, &c. we get, Page ¥ ad? G GB d > 2 death Ua Sica or ha a: called Taylor’s theorem. This theorem is as universal in its application in the theory of increments, or differences, as the binomial theorem is, in the expansion of roots and powers.—(Mr. Barlow’s Dictionary ; Article, Increment.) In order to find the increment of any function of a variable’ quantity, we must take the first, second, third, &c. differentials of the given function, and divide the results by 1, 2, 2 x 3, 2 x 3 x 4, &c. respectively, and we shall have the value of A @; which will always be finite unless the function be tran- -scendental. Example 1.—To find the increment of x. The first differential of « is da, and the second differential of x is zero, because d xis supposed constant ; therefore Ax = dz. Example 2.—To find the increment of 2°. dxt =2adu,andd(2Qrdz) +2 = d2*=A 2 (example 1); therefore A (a?) = 22 Ax + Aa® (dz constant). Example 3.—To find the increment of 2°. d(#) = 3atdax;dBa2dz)+2=32adrx°; d(8rd2*) = 6 = dx; therefore, A(a®) = 307 Axr+3rAa+ Axi (dx constant). Example 4.—To find the increment of 2”. dx") = mz" da, d(ma"—' d 2) =m (m— 1) 2*~*, dw, d (x (m — 1) a-"'da*) = m(m — 1)(m — 2) a" da’, Ke. By writing A x for d x, and substituting in the general theorem, m (m — 1) 2 + &c, which is commonly we have A (2*) = ma"™"*Axr-+ ee a m (m — 1) (m —2) 2.3 Example 5.—To find the increment of x (vx + A 2). d(a? +xrda)=2redzr+dzx%,andd(2rdz) =2d 2°, then m—3 A y® + &c. (d x constant.) -1820.] of Taylor’s Theorem, &c. 101 by substituting in the general theorem and writing A x for d x, we get A fx (x + Arh} = 2Ax(e + Ax); (dz constant.) Example 6.—To find the incremedt of x (a+ Aa)(x4 +2 Az). In order to simplify, put w = A x, a constant quantity ; then wild {x (@+ Ax) («t+ 2Arx) =d(i + 3wa* + 2w* 2) =3wr+6wr+2w,dBwa?+-6w2 xr) = 6wr xt 6 w*, and d(6 w* x) = 6w3. Then by substituting in the gene- ral theorem, we have the required increment; viz. 3 w a? + 9w?x+ 6w? =3 w(x + w) (x + 2w), by restoring Aa, we get A fx(a+Az)(x+2Ax)t =3Axi(x+Anx)(x+2A xz). Example 7.—To find the increment of x (vw + Ax) (x +2Aqz) (x7 + 3A 2). Put A x = w, a constant quantity; then will the above expression become x* + 6 w 2° + 1] w* a + 6 w> x, then will d(x'+6w2i+ll wx? +6w x)= 4w2?+ 18 wir? + 22w'r+ 6w* d(4w2°+ 18 w*x? + 22wir)+2=. ....4 6wix?4+ 18w3e+1l wt Re aera ford O. Ue) 0. Fs ier echt ata, » ne ors + 4w>x+ 6u* yal Sad Ie Oe dl ome e na ig a a eae + w* The required increment .... =4zw2° + 24w%1?+ 443 et 24wi= 4w(+6wartllwrt 6w*)=4w (e+ w) (w+2w)(e+3 w)) = 4Ax((a + Ax) (v+2 Ax) (2+ 3A2)). Hence we conclude that A (w@@t Ax) +2Ax) ....(@ + nAx))=(ntl Aa (@+Ax)@+2Aq) faut (c+ nA2)). Example 8.—To find the increment of = Putw=dxr=A x, aconstant quantity, then will 1 pie al elec oh LN — wo? 24 a 3 Z wee ==; d2Qwa + 6=>-we t= — = 18cc: 1 w 107 103 { ] Therefor ()=-< eee. Cote ais +. e eAl- 3 oe sa + &e. Sa ee w par Agr x(x +w) x(x + Ax)” ; 1 Example 9.—To find the increment of mt Put w = dx = Az, a constant quantity, then will \ Bis 2w a(-) =d(«) = — 2 wert T del "S eae tyre 2 =3 2 —4 3 w? — Sow r*=—,d 6wiae'") +6= —4 Ur 5= — a 43 1 20 3 w? 4 w3 => &c. Therefore A (a i aaa age enn ( 1 ye pe ie 2wrew? Qxr Ax + A c+ w ch (epee ate t+ Aw)? 102 Mr. Adams’s Demonstration {Frs. Example 10.—To find the increment of — Put w = dx = Az, aconstant quantity, then will 1 d(=)=d@a™) = -—mwa-™=—m ore ‘ bh =\(m 3) _ m(m +1) w? d(— mwa-™*”) + 2 ots FS See barb (m + 1) (m + 2) w3 d(m (m+ l)w* x mr). 6 = 7m ee Pr) Xe 2.072 R70. es ee eseveeeereeeee @eenv40eeoes eevee epeeeee eeseevee } 2 Therefore A (4) = —m. ete —— = Boe, ax zms0 2 eut2 cieak 2 ' : mw xe™—* + wc be LiL cae io + &ce. (+) «ap =™ (2 -+- )™ Example 11.—To find the increment of log. «. Put w = dx = Ax, a constant quantity, and y = log..a, then @y wt dy us dty aot S= > 2 2iz?” 16 323? 24 4 at ny Py By dty i w w? ws wt therefore d y + PG oe Uk ea et oa ey ae + &e. Ag Air? A wy, Aja r 7) = —_— — arta: vc. or A (log r) x 2 a* 3.23 A at vig Example 12.—To find the increment of x log. x. Put w = dx = A x, aconstant quantity, andy = x log. x, then dy = wlog.xr + w = w (log.x + 1), = = all Baxi = " oie 6 ws diy wt dy 205 " 62” ye = Te Fi ee =—_— — 20 20 a! &e. Therefore, dy a. ee vig. By ay satis a =" ra + Ke. = w (og. 2 41) 4 ws oF Cog. Ax A xt Az =Azx (log.2 +1) 42 + &c. Example 13.—To find the increment of (log. «)". Put y = log. x = /2, then will A (log. x)" = A(y"); but by m(m—1)y —?2 A 2? Sn Se + &c. by substituting for y, we have A (log. x)" = m(la"~'Ala+ a el + &c. The values of A la, (Alz)2, (A / x)*, &c. may be expanded into a series, if necessary, by example 11. Lixample 14.—To find the increment of a’*. Suppose dx = Ax, a constant quantity, and y = a’. ~-SS 3.4.03 4.5.2% example 4, A (y") = my"™""Ay + 1820.] of Taylor’s Theorem, &c. 103 Then will log. y = ly = « la, and d (ly) = “2 = dala. Therefore ees y.da.la @y=dy.dz.la=y.dx*(l a)* GBy=— dy. dx lade — 7. dx (la). d*+y=dy:dzx'(la)s =y..d x* (l.a)* BE = ye sep syst vhv ohacercty an ieee ale, « i Then Ay = A(@) = dy + 4544 59" 4+ &e. Or (@) = y.dx.la + PAO 4 pert + &e. =a (A aida + aes + i + &e. ). Ifa =e, be the number whose logarithm is unity, then Ja, (J a)’, (4 a)’, &c. are each equal to unity, we shall then have Ee ae & 2 A x3 A xt : A@)=e (Avot 4554 SF + &e. Example 15.—To find the increment of sin. x (radius unity). Suppose d x = A x = w, aconstant quantity, and y = sin. x. »’” = e* (e4* — 1): Thend y=d_ (sin.2) =+w co.x= +A cos.x2 dty=d( w cos.2) = —w? sin. x = — A x? sin.x d’y=d(—w?* sin. x) = — w3 cos.x2 = — Ax cos. x d+y=d(—w' cos.x) = +wtsn.x = + Art sin.e d>y=d( w*sin.x) = + w*sin.x = + Ax, cos. 2 < a d3 dt : Therefore A y = A(sin.x) =dy + — + al Seed wi + &e. Or A (sin.z) = A xcos.2 — as j ae cos. x + Os eg 2.3.4 A x5 2.3.4.5 Example 16.—To find the increment of cos. x (radius unity). Put w = dx = Ax, a constant quantity, and y = cos. x. feed 7 = 2 (cos, '\r)... 5. = — wo sine — Ar sm. & d?y=d(—w sin.x) = — w?cos.x = — Ax? cos.£ d3 y = d(— w? cos.x) = + w? sin.xw = + Ax’ sin. © d+y=d( w® sin. x) = + wtcos.x = + Axt cos.x PM ala als, ole ise pisie vncieave's case cin as ced EMS verve d3y dty 23° 2.3.4 sin. 2 + cos.2 — &e. Therefore A (cos. x) = dy + pi + &c. Or A(cos.x) = — Ax sin. x — A> cos. xt+ sy sin. « + Azt 37974 008. & — &e. Example 17.—To find the increment of tan. x (radius unity). Put w = dx = Ax, a constant quantity, and y = tan. x. 104 Mr. Adams’s Demonstration fFex. Then dy = wsec?x ad? > = w? tan. x sec.2 x dy w3 = = -| (2 tan. x sec.? x + sec.‘ x) ad wt an = — (tan.? xsec.2 x + 2 tan. w sec.* 2) Gy wip 4 4 CG Te (2 tan.‘ xsec.? x + 1] tan.* x sec.* x + 2sec*u} St Gaerne pa eat Seay) TS AA Aine een ost otis r writing an.? a for sec.” x, we have Or by ting 1 + tan. a fi aE h ree SE ey. ae A (tan. ce) = ay tz test ag gat = + Axsec? x aA a? tae 2 S€C.a7 A 23 -+ pbs + 3 tan.? x) sec.? x + “= (2 + 3 tan.’ r) tan. rsec.2 x + = (2 + 15 tan.2 2 + 15 tan.4 x) sec’ x + ae (17 + 60 tan.2 x + 45 tan.‘ x) tan. z sec & Bie occ RE es NS. aR oe oie Example 18.—To find the increment of cot.x (radius unity). Put w = dx = A x,aconstant quantity, and y = cot. a. Then by a process similar to that used in example 17, we have A (cot. x) ='—_A'r cosec.? ¢ + A x* cot. x cosec.? x A a3 : (1 +3 cot.® x) cosec.® x — 4 f3 = (2 + 3 cot. x) cot. x cosec.* x - a (2 + 15 cot.2x + 15 cot.* x) cosec? x 6 + “3 (17 + 60 cot.2x + 45 cot.* r) cot. x cosec* x COCR BRYA Fie deat othe OO aR SRB. IoCday ied ae Mr. Ingham’s...| 15 1 0 I 0 7 3 3 4 34 Mr. White’s ...| 19 7 3 0 0 3 2 ie] ou 35 Mr. Hey’s ..... 9 4 2 0 o}| 7} 2] of] 1{ 25 Mr. Ainswoarth’s T 2 2 1 0 6 2 1 2 23 Own collection.| 21 8 4 6 2 16 7 6 0 70 i. | 22 11 8 2 39 ' 16 ' 11 7 | 1ST From the preceding table, I have calculated the following, exhibiting the proportion which each kind of concretion bears to the whole number in the different collections. For example, in Mr. Ingham’s collection, the calculi consisting chiefly of uric acid are to the whole number as one to one and two-tenths ; in Mr. White’s as one to one and eight-tenths, the second decimal figure being omitted throughout as unnecessarily minute. * Especially by most of the late and present surgeons of the Manchester Infirm~ ary; and to Mr. Ransome, one of the surgeons of that charity, Lam indebted for dividing the calculi by a saw, without which division, collections of urinary con- eretions can atYord no useful information, 1820.] Dr. Henry on Urinary Calculi. 109 Taste II. Showing the Proportion of each Variety of Calculus to the whole Number in the different Collections. Boe a mot g Brac tied insi,.2 bogemilekeiantabe Kind of calculus. zs =2 a = FS vis z = = = Zz Z = io) cS o eo oS Pa Ee 8 =2 4 = a | <4 = Chiefly uricacid ............ lto 2°2jlto L-Sjlto 2°7|lto 3°3\lto S*2ito 26 Earthy phosphates. ..... Sooke S40 9 SOL FOO Tibi SSAC sb Oxalate of lime ....... Soh ibe — |L 6 12-011 LbSt TTL 17-0 Compound..,.......- ave stese 1 340) — — fl 23-0/1 1181 23-5 Pepa te teers steuis aoe ajo 1 2°0)1 SQ SA. ADO) GSA. Bek 88 ¢Uricacidand plosphates|L 4-8/1 1-61 34)L S81 441 48 ‘S | Oxaiate and phosphates..J1 21-2) 1T5L 1201 T5t OL 116 FS Oxalateand uric acid....|1 ll-2]1 35:0) — 1 23-0|\L 11°81 17:0 © | Uric acid oxalate and | = | phosphates.........-.-[1 85) — 1 240)1 11-5) — 1 265 ROW REIC RANE (oso opin sae ciacoe'e _ _ = — — jl 985 The greater proportion of uric acid calculi in Mr. White’s col- fection than in that of Mr. Gibson and Mr. Ainsworth may, on first view, appear extraordinary, as those three gentlemen all practised surgery in the same town. It will be found, however, in the joint collection of the two latter, to be compensated by a much greater number of that variety of alternating calculus which is composed of uric acid and the phosphates in distinct layers. It may be remarked also that the greater number of Mr. White’s operations were perforined at a very remote period of time, when litle interruption was given to the natural progress of the disease by the use of alkaline medicines, and that his patients were chiefly from a distance. Of late years, in conse- quence of the increase of public hospitals in the adjoining coun- ties, cases requiring lithotomy occur comparatively very seldom at the Manchester Infirmary ; and the town, and district im- mediately surrounding it, may be considered as remarkably unproductive of stone patients, though cases of gravel occur, 80 far as 1 have the means of judging, as frequently as in other remote districts.* In the collection of Mr. Ingham, of Newcastle, the proportion of calculi composed entirely of the earthy phosphates is un- usually small, but is compensated by the number of concretions in which the phosphates alternate with uric acid. On the whole indeed there is a remarkable uniformity in the composition of * It isa well ascertained fact, and one which should give encouragement to persons labouring under gravel, that this disease occurs very frequently without degenerating into stone ; and that it is even endemic in districts where the stone is a very rare dise.se.—(See Beverwyk de Calculo, p. 78, Carleton de Lithiasi, p. 118, and Heberden Comment. p. 78,) 110 Dr. Henry on Urinary Calculi. [Frs. calculi generated in districts very remote from each other—a fact which proves that the causes rendering the stone endemic in certain countries act, not as was once imagined in supplying directly the material of which the concretions are composed, but in inducing a constitutional tendency to the disease. - It was the opinion of some of the older writers, that all calcu- lous concretions (with the exception of such as are formed on extraneous substances accidentally introduced into the bladder) do in fact originate in the kidneys, and descending through the ureters, merely acquire an increase in the bladder by attracting solid matter from the urine. To this opinion, which Fernelius especially has ably supported,* it has been objected that stone in the bladder is in many instances not preceded by any pain in the region of the kidneys, or by the symptoms that denote the descent of a stone through the ureter.} [t is perfectly conceiv- able, however, that a small calculus may find its way from the kidneys to the bladder without exciting pain in its passage. The opinion of Fernelius, and of others who agree with him, I find also to be confirmed by the appearance of almost all the calculi which I have ever examined, after having been divided by the saw ; for, except in very few instances, a central! nucleus may be distinctly seen, sufficiently small to have descended to the bladder through one of the ureters, even when that passage has not been dilated beyond its natural diameter. The stone, there- fore, is to be considered, essentially and in its origin, as a disease of the kidneys. Its increase in the bladder may be occa- sioned either by exposure to urine containing an excess of the same ingredient as that composing the nucleus, in which case it will be of uniform composition throughout ; or if the substance composing the nucleus should, either by a spontaneous change in the action of the kidneys, or by the effect of medicines, be secreted in less than natural proportion, the concretion will then, like any other extraneous body lodged in the bladder, acquire a covering of the earthy phosphates. Under this view of the subject, it becomes highly important to ascertain of what ingredient the nuclei of urinary calculi are, for the most part, constituted, since it is in the tendency of the kidney to generate this ingredient that the primary cause of the disease must consist. Of the 187 calculi which I have examined, 17 have been formed round nuclei composed chiefly of oxalate of lime; 3 round nuclei of cystic oxide; 4 round nuclei of the earthy phosphates; 2 round extraneous substances; and in three, the place of the nucleus is supplied by a small cavity, occasioned probably by the shrinking of some animal matter, round which the ingredients of the fusible calculus had been deposited.{ The remainder, amounting to 158, have a central * Fernelii Opera, p. 317, folio. + Beverwyk de Calculo, p. 69. $ Rau has shown, bya direct experiment, that pus may form the nucleus of an urinary concretion,—(See Denys de Calculo Renum, &c. p. 14.) 1820.) Dr Henry on Urinary Calcul. 111 nucleus composed chiefly of uric acid. It appears then that in a very great majority of cases, the disposition to secrete an excess of uric acid, has been the essential cause of the formation of stone ; and it becomes important to inquire what are the cir- cumstances that contribute to its excessive production, and by what plan of diet and medicine the tendency to its too great secretion by the kidneys may best be counteracted or removed. This inquiry, however, is not within the scope of the present essay, which is limited to the chemical composition of the con- cretions when actually formed. Of Uric Acid Concretions. It has never yet occurred to me to examine a calculus com- posed of this acid in a state of absolute purity. Of the concre- tions which [ have classed under this head, a considerable number, after the action of pure potash, have left an insoluble residue of the earthy phosphates ; and from the solution of those even, which have entirely dissolved in that menstruum, [ have inno case been able to recover by the addition of acids, a quan- tity of uric acid equivalent to the weight of the calculus dissolved. The utmost that I have ever obtained has been 92 parts from 100 of an uric concretion. On this subject, therefore, my expe- rience entirely agrees with that of Mr. Brande.* The loss doubtless arises from the decomposition of animal matter by the alkali. This, as I have stated in my Thesis, is partly urea, which I found may be separated by digesting the powdered calculus in alcohol, and evaporating the solution.+ It is not, however, to urea that the colour of uric acid calculi is to be ascribed, but rather to the other substances which in urine gene- rally accompany it ; for it has been shown by Professor Berzelius and by Dr. Prout that pure urea is destitute of colour. In one instance only I have observed a vesical calculus composed chiefly of uric acid, to be of the whiteness of chalk ; and from this the action of alcohol did not extract any portion of urea. Gelatine I have never been able to discover, by applying its appropriate test to water which had been digested in the pow- dered calculus ; but the presence of aibuminous matter appears to me to be indicated by light flocculi, which sometimes float over the uric acid, when precipitated by acids from its solution in alkali. It is probable, however, that the characteristic ingre- dient of urinary calculi does not necessarily require a cement to bind it together, but that the aggregative attraction of its par- ticles is sufficient to unite them into a compact mass. All curative plans, therefore, which have in view the removal of a cementing ingredient (the mode in which Haller and Hartley explained the action of alkaline solvents) appear to me to be without probable grounds of suceess. * Phil. Trans, 1808, + Dissert, Inaug. 1£07, p. 39, 112 Dr. Henry on Urinary Calculi. [Fes.. Urate of ammonia, I believe with Mr. Brande, has been erro- neously set down by Fourcroy and Vauquelin as an ingredient of urinary calculi. At least I have never found any indications of its presence in calculi which had been previously subjected to _the successive action of alcohol and of acetic acid; menstrua, which would remove urea and the ammoniaco-magnesian phos- phate, but would not, in the quantities employed, have separated urate of ammonia. Several opportunities have been thrown in my way of examin- ing urinary calculi, extracted from persons who had been long under a course of caustic alkaline lixivia. In one of these (No. 13 of Mr. Ingham’s collection) the outer surface of tHe calculus might, on first view, have been supposed to have been eroded ; but a closer examination satisfied me that the appear- ance was owing, not to the sclution of the uric acid, of which the concretion chiefly consists, but to an irregular deposit of the earthy phosphates, occasioned probably by the medicine. Ano- ther calculus in the same collection (No. 15) taken from a person who had long been using Perry’s solvent, was so brittle, that on attempting to divide it by the saw, it separated into con- centric coats, composed of uric acid with a large proportion of the earthy phosphates. The third is a fusible calculus, now in my possession, of remarkable whiteness and compactness, and containing no @ppreciable portion of uric acid. In a fourth instance, a calculus, put into my hands by Dr. Brown, of Glas- gow, which had been taken from a person after so free an use of alkaline medicines as to have injured his general health, con- sisted chiefly of the triple phosphate of ammonia and magnesia. It was so brittle that it broke almost into powder under the forceps, and was, therefore, extracted by the scoop. These cases, and others of the same kind, which I think it unnecessary to mention, tend to discourage all attempts to dissolve a stone supposed to consist of uric acid, after it has attained consider- able size in the bladder ;, all that can be effected under such circumstances by alkaline medicines appears, as Mr. Brande has remarked,* to be the precipitating upon it a coafing of the earthy phosphates from the urine, a sort of concretion which, as hha& been observed by various practical writers, increases much more rapidly than that consisting of uric acid only. The same» unfavourable inference may be drawn also from the dissections of those persons in whom a stone has been supposed to,be dis~ solved by alkaline medicines ; for in these instances it has beer found either encysted or placed out of the reach of the sound by an enlargement of the prostrate gland. The former source. of - fallacy was shown to have existed even in one of the cases whieh procured to Mrs. Stevens the parliamentary reward of 5000/.; + * Philosophical Transactions, 1808. + Newman’s Inquiry into the Merits of Solvents, London, 1781. ." * 1820.] - Dr. Henry on Urinary Calcul. 113 ~ and examples of the latter kind have been related by Dr. Heber- den and Sir Everard Home. Two instances have fallen within my knowledge, in which persons have voided quantities of uric acid with the urine, far exceeding any thing that I can find upon record. In the first, which was mentioned to me by Professor Monro, of Edinburgh, every pint of the urine voided by a man about 40 years of age, who laboured under symptoms of gravel, deposited about two ounces of a brick-coloured sediment, which I found on examina- tion to be chiefly uric acid with a very small relative proportion of the earthy phosphates. In another instance, a lady of middle age, who was subject to gravel, was in the habit, when warned of its approach by the usual symptoms, of having recourse to a medicine, the composition of which is kept secret, but which appears to me to be nothing more than spirit of turpentine coloured by a little petroleum, with the addition of a portion of tincture of opium. The uniform effect of this medicine was the discharge of a sandy substance in such quantity that more than four ounces were sometimes veided within the space of two or three days. It was composed chiefly of uric acid, with a small proportion of urea and of the earthy phosphates. I have since known another instance in which the same medicine has produced a similar effect, though not to an equal extent, prokably by acne as a stimulant to the kidneys, and clearing them by the increase flow of urine which it excites of the sand that had been depo- sited in the tubuli uriniferi and pelves of those organs. Calculi composed chiefly of the Earthy Phosphates. The pure phosphate of lime, or bone earth calculus, I have not been able to recognize in any of the collections of calculi which I have examined, though assisted by a recollection suffi- ciently distinct of one which was shown to me some years ago by Dr. Wollaston ; nor have I ever found the triple phos- phate of ammonia and magnesia composing, in a pure state, an entire calculus, though in Mr. White’s collection there is one containing more than 90 per cent. of that salt. From this pro- portion I have found it in a variety of others, down to 20 and even 10 per cent. With phosphate of lime, in proportions which seem to have a considerable range, it constitutes the fusible calculus, and this mixture forms the principal ingredient of calculi that have concreted round foreign substances. A calculus in Mr. White’s collection, the nucleus of which is a bougie that had slipped into the bladder, is composed of | ¥ Phosphate of lime. .......... 20 Ammoniaco-magn. phosph.,,.. 60 Dic ACIG, s.Nauwe veces src ave. LO Animal matter. }.i.es00cs0000 10 100 Vou. XV. N° Il, H . 114 Dr. Henry on Urinary Calculi. (Fes. In four instances only out of 187, the calculus has been com- — posed throughout of the earthy phosphates ; and in these I have not been able to discover a nucleus of any other substance. I consider the fact, therefore, as sufficiently established, thatin some instances, though comparatively very few, a tendency to secrete the earthy phosphates in excess is a cause of the formation of stone, first probably in the kidneys, and subsequently in the bladder. This tendency indeed, as is well known, sometimes manifests itself by the discharge of urinary gravel, consisting of the triple phosphate either alone or in conjunction with phosphate of lime. Several years ago, the Rev. Mr. R. of Cheadle, in Stafford- shire, consulted me respecting a train of very distressing symp- toms, some of which evidently denoted considerable disease in the kidneys. His urine, which at some times was perfectly limpid, was at others loaded with a white substance, which gave it, when first voided, the opacity of milk. On standing, a copious deposit took place, a portion of which was sent to me for examination. It was perfectly white, and so impalpable as to resemble a chemical precipitate. On analysis, it proved to con- sist of nearly equal parts of the triple phosphate and phosphate of lime. The discharge of this powder was always preceded by violent attacks of sickness and vomiting, and its quantity was invariably increased whenever he took soda water or any other alkaline medicine. Beside the affection of the kidneys, there appeared to me to exist important disease of the chylopoietic viscera, and to this I ascribe his death, which took place a few months afterwards. In this case it was remarkable that the weight of the body was reduced from 183 to 100 pounds at rather an early stage of the disease, without a corresponding degree of muscular emaciation, owing obviously to the imperfect nutrition of the bones, in consequence of the waste of the phos- phate of lime through the urinary passages. Mulberry Calculus. In calculi of this description I have always found, with Dr. Wollaston and Mr. Brande, an admixture of other substances with the oxalate of lime, which is to be considered as their characteristic ingredient. One of the best marked specimens I have ever seen cf the rough kind afforded, from 10 gr. 5°3 gr. of carbonate of lime, equivalent to nearly 6-6 of oxalate, 1 gr. of uric acid, 0:3 gr. of phosphate of lime, and a quantity of dark- coloured floceuli of animal matter, which did not descend along with the uric acid, when the latter was precipitated from its alka- line solution. These flocculi were soluble again in pure potash, but not in alcohol or in dilute acids. The colouring ingredient of this variety of calculus is communicated both to caustic alka- lies and to concentrated muriatie acid, the latter of which becomes tinged, like a strong infusion of roasted coffee. On diluting the solution, part of the oxalate of lime is deposited, but the colour- 1820.] Dr Henry on Urinary Calculi. 115 ing matter remains dissolved. I[t is probably derived originally from effused blood, for the smooth variety of calculus which con- sists chiefly of oxalate of lime, is not distinguished by this dark shade of colour. Cystic Oxide Calcul. By means of Dr. Woliaston’s clear description of this rare variety of calculus, I have recognised two specimens of it in my own collection, but with the histories of both I am wholly unac- quainted. They have obviously been extracted from the bladders the one, when entire, weighing 660 gr. and the other 334. In each, the nucleus is the same substance as the rest of the con- cretion ; and in a third specimen, also in my possession, a very small spherule of cystic oxide forms the nucleus of a moderately sized calculus, the rest of which consists of uric acid. This oxide appears, therefore, as Dr. Marcet has properly remarked, to be in reality the production of the kidneys, and not, as its name would import, to originate in the bladder. Calcul, the Ingredients of which are disposed in alternate Layers. Of these I have little more to observe than will be suggested by inspecting the first table; viz. that calculi composed of layers of uric acid and the earthy phosphates are, in the collections which I have examined, the most frequent variety of the alter— nating kind; next follow those of oxalate of lime and the phos~ phates ; then concretions of oxalate of lime alternating with uric acid; and lastly, those occur most seldom in which the three substances just mentioned alternate together. I have not met with an instance of a calculus containing four ingredients in distinct layers; and it appears, from the testimony of others, that such examples are extremely uncommon. Foreign Substances voided in the Urine. I have related, in a periodical medical journal,* the case of an elderly gentleman, who discharged in his urine the larvze of an insect, which, when first voided, were alive and vivacious, and so far as could be made out by an eminent naturalist, belonged to some species of the coleopterous order. In this case, though the patient would not consent to be sounded, there was doubtless a stone in the bladder, and, as appeared to me, extensive disease of the bladder itself and of the prostate gland; but no examination I believe was made after his death, which was occasioned suddenly by a fit of apoplexy. i have lately been made acquainted, by a gentleman of middle age, with a singular discharge which he frequently observes in his urine, of a considerable number of short hairs. Besides that he is above all suspicion of being deccived himself, or deceiving others, I have satisfied myself, by the most careful investigation, * Jdin. Med. Journ, vii, 147. H 2 7 116 Dr. Henry on Urinary Calculi. [Fes.. that they have their origin from the inner surface of the bladder, or from some of the urinary passages. They are of various lengths, from one-tenth of an inch to an inch, and now come away without giving him any uneasiness, though he has at times suffered pain from the discharge of gravel of the uric acid kind. On one occasion, the hairs which were voided had acquired, before their discharge, a distinct coating of uric acid. The symptoms having at one time excited suspicion of a stricture of the urethra, a bougie was twice introduced without giving him pain ; nor was its use followed by any increase of the number of hairs that were voided, which might perhaps have been expected, if they had grown from the membrane of the urethra.* Of Morbid Concretions from other Parts of the Body. Pulmonary Concretions.—A pulmonary calculus, expectorated several years ago by a patient of the late Dr. Ferriar, was found to be chiefly composed of phosphate of lime, with a very minute proportion of carbonate. Such also has been the com- position of other specimens, given to me by Dr. Baron, of Gloucester ; but a remarkably large one in the possession of Mr. Ainsworth, which weighed, when entire, 51 gr. and exhi- bited a complete cast of one of the bronchial cells, is principally composed of the triple phosphate, with a very small relative es Heke of phosphate of lime, and a mere trace of carbonate. ome concretions taken from the lungs by the late Mr. Allan Burns, of Glasgow, have their earthy part composed of about one-fifth of the triple phosphate, and four-fifths of phosphate of lime, with a minute proportion of the carbonate of that earth. The subject from whom these concretions were taken after death, I was informed by Mr. Burns, was a female about 15 years old, who, though affected with violent cough, had never expectorated any calculous matter. The spine in this case was so much incurvated that, towards the close of life, the face approached nearer to a horizontal than to a perpendicular line. The sub- stance of the lungs when grasped was felt to be full of hard knots, from the size of a pea to that of a hazel nut ; and a concretion, about the size of a large musket-ball, was found firmly impacted in the left branch of the trachea, near to its origin. By a care- * ‘When examined chemically these fibres do not appear to differ from commor hair; but it has been observed by Dr. Wollaston, that they differ in some respects. io their mechanical texture, since they have not that slight roughness in one direc- tion of the surface on which the felting property of common hair of every kind depends. This property of hair is most distinctly shown by pressing it betweer the fingers, and at the same time sliding the fingers upon each other in the direction of the hair, which will by this motion be seen to travel forward with its root fore- most. The finger which moves from the root slides freely along the hair, while the other finger is prevented from sliding in the opposite direction by a degree of roughness (which is thus sensible though not in any way visible) but in its turn this finger also will move from the root while the hair now rests against the opposite finger, It bas also been remarked by Dr, Wollastun, that common hairs are not really tubular, as has oftea been asserted, but that these fibres really are so, 1820.) Dr. Henry on Urinary Calculi. 117 ful examination of the concretions in the substance of the lungs, Mr. Burns ascertained that each was lodged in a bronchial cell, and was enveloped in a distinct capsule, which admitted of being readily separated from the membrane of the air cell. Indeed in all concretions discovered in the soft parts of the body, Mr. Burns informed me that he has uniformly found a peculiar substance containing the solid substance, and over this another sheath of dense membrane. The inner covering he supposed to belong essentially to the concretion, and the outer one to be formed in consequence of the irritation caused by the presence of an extraneous body. Calculi from the Spleen.—For the opportunity of examining these, 1 was indebted to the same zealous and able anatomist. They were of small size, shaped like a pear, of a yellowish-white colour, and were composed of bone earth, without any portion of the triple phosphate. Small Crystals formed on the Surface of a cancerous Prepara- tion, kept in Spirit of Turpentine.—These also I received from Mr. Burns ; and though not strictly belonging to the class of morbid concretions, 1 mention them here on account of their singular composition. They are in very minute parallelopipe- dons, are fusible when placed on a piece of iron heated below redness, and evaporate in an aromatic smoke. They are very sparingly soluble in water, but more so in alcohol; and the latter solution, when concentrated, reddens litmus paper. They agree, therefore, in their properties with the camphoric acid, and fur- nish an instance of the production of that acid under circum- stances not before observed. Whether they had passed through the intermediate state of camphor, which, by well known treatment, may be obtained from spirit of turpentine, it is now impossible to ascertain. Mr. Burns, however, assured me that they may not unfrequently be seen on preparations kept in that fluid; but never, except when the parts have been imperfectly dried before being immersed in it. It is probable, therefore, that they may be found under similar circumstances in other anatomical collections. Manchester, Dec. 16, 1818. ARTICLE V. Memoir on Sulphuric Ether* By John Dalton. In my essay on the force of steam, read before the Society in 1801, and published in the fifth volume of the Memoirs, I stated some experiments on the force of vapour from sulphuric ether, © Read before the Literary Socie:y at Manchester, April 16, 1819. 118 Mr. Dalton on Sulphuric Ether. | (Fes. at different temperatures, as exhibited in a Torricellian vacuum, also the force of the same when admitted into a limited portion of air. From these experiments, as well as from corresponding ones made with water, alcohol, and other fluids, I was led to adopt the important conclusion, that steam acquires the same - force in air as in a vacuum, and that it ought to be considered the same independent fluid in both cases. Consequently if p denote the pressure of any given volume of air (1), and f denote the pressure of steam of a given temperature, such steam being adnutted to the air, the volume of both in due time becomes P aed ' This theorem is most beautifully illustrated by sulphuric ether. Let acomraon barometer have a drop of ether let up into ‘the vacuum; it will instantly depress the mercury several Snches, more or less according to the temperature. Suppose it were 10 inches, the barometer being 30 ; then ; a = 1:5; that is, if ether be passed up into air under those circumstances, it -will in due time increase the volume of air 50 per cent. For_six years after this I was occasionally engaged in the fur- ther investigation of the nature and properties of ether, in which several additional facts, and some corrections of those antece- dently announced, occurred. The combustion of ether was effected in various ways, as well as its analysis, by heat and by electricity. ~ During all this time I procured my ether in small quantities at a time, and of various druggists, as suited my convenience. Once or twice I ascertained the specific gravity of the article to be at or near 0°75; and [ never found reason to suspect there was much difference in the specimens. Occasionally when great part of the ether was evaporated by time and neglect, I found a few drops at the bottom of the phial, which did not possess the properties of ether, but this was too small to be much regarded. In an excursion to Edinburgh and Glasgow in 1807, I exhibited the steam of ether, as above described, to a few persons in those two places ; when at the latter place, Dr. Ure was so good as to supply me with ether, but upon trial it did not present the properties I had usually recognized, which at the time J attributed to accidental impurities, acquired in the labo- ratory ; upon this he accompanied me to a druggist, where I was immediately supplied with ether of the requisite purity. I apprehend Dr. Ure’s ether must have been the spiritus @etheris sulphurici of the Edinburgh college, made by adding two parts alcohol to one of ether; or perhaps ether not rectified. . In 1808 I published the first part of my New System of Che- mical Philosophy, in which I digested all the knowledge I then had on the force of steam from ether in a tabular form. I had acquired from actual observation the forces in a range of tem- 1820.] Mr. Dalton on Sulphuric Ether. 119 perature from 0° to 212°. In my former publication f had concluded that the variations in the force of steam from water and ether were the same for the same intervals of temperature ; that is, if the force of steam from water was diminished from 30 to 15 inches of mercury, by a diminution of temperature of 30°; then that of ether would be diminished from 30 to 15 inches by the same number of degrees, though in a much lower part of the scale; the former being from 212° to 182°, and the latter from 98° to GS°. Subsequent experience, however, led me to appre- hend that the above intervals of temperature, though expressed by equal expansions of mercury, are not in reality equal intervals ; but that equal intervals are rather denoted by the forces of steam being in geometrical progression. Consistent with this view I found tl.etsteam from water and ether would concur, for a long range of temperature, with the diterence of ratios only ; that of water being 1-321 for 10° of temperature, whilst that of ether was 12278. In the above work occurs the following observation: “ Ether, as manufactured in the large way, appears to be a very homoge- neous liquid. I have purchased it in London, Edinburgh, Glasgow, and Manchester, at very different times, of precisely the same quality in respect to its vapour.” This observation, though warranted from my limited experience at the time, I now find not altogether correct; I am sorry that it has occa- sioned an ingenious experimentalist to be lea into a labyrinth of error. The bulk of the ether used in this country has I find of late years been prepared by one manufacturing house in the neigh- bourhood of London. ‘Three qualities of the article are made according to the different uses intended. The highest quality is only made for particular purposes, and is, therefore, not very commonly met with; it is about 0°73 specific. gravity; the second quality is that intended for medicine ; it is of 0°75 speci- fic gravity, and is that with which all the country druggists and apothecaries are or ought to be supplied as a standard uniform article ; it is that which { have always met with in the shops, and which I have taken for genuine ether in my former experiments. The third quality is of the specific gravity 0°78 or 0-79 usually ; of course it is much inferior to the last in purity. But itmay be proper to observe, that this is the first state of the other two qualities ; they being produced from this by ulterior processes called rectification. it is well known that sulphuric ether is procured by distilling a mixture of sulphuric acid and alcohol. The proportions usually prescribed are equal weights of concentrated acid and alcohol. By due management, a liquid of the specific gravity 0-785 or 0°79 is obtained, called ether. It is the ether of the third quality, just mentioned, and is in fact a compound of 120 Mr. Dalton on Sulphuric Ether. [Fes. alcohol and ether chiefly, in proportions to be investigated here- . after. In this state it is usually called unrectijied ether. When this last liquid is redistilled by a moderate heat till one half has passed over, the liquid in the receiver is denominated rectified ether. It 1s usually about 0°75 specific gravity, corre- sponding to the second quality. It still consists of ether and alcohol, but with much less alcohol than before. There is great reason to believe that both the wnrectified and rectified ether, as thus prepared, are destitute of water, except so far as it is an essential element of the two liquids, ether and alcohol in their purest states ; the sulphuric acid being well able to retain all the excess of water of common alcohol in the temperatures employed in the two distillations. Ether of the first quality, or that in its purest state is to be obtained from the rectified ether just mentioned. The object is to abstract the alcohol still remaining in tha rectified ether. This may be done in great part by repeated distillations ; always taking the first produce and setting aside the remainder for other use ; but this method is tedious and expensive. A more ready . method is to agitate the rectified ether with about its own bulk of pure water; after agitation the mixture resolves into two fluids, a heavier and a lighter; the lighter may be decanted, and will be found about two-thirds of the volume of ether used ; it will have the specific gravity 0°73 nearly, and may be considered as ether of the first quality. But it is demonstrable that it still contains some alcohol, and has besides acquired a portion of water from this process. The watery stratum below contains the greatest part of the alcohol, and has also taken along with it a portion of ether, as is evident from the smell, which 1s much the same as that. of ether itself. This heavy liquid has the specific gravity of 0-96 or 0:97 usually. If this ether of 0°73 specific gravity be again treated with water, it will be reduced nearly to 0°72 specific gravity ; but it still contains minute por- tions of both alcohol and water, the quantities of which are not easily appreciated. Subsequent distillation would doubtless improve the quality a little; but for most practical purposes there is reason to believe that no material difference would be found between the above and ether of absolute purity. Having obtained ether of the specific gravity 0-72, and alcohol of 0-83 specific gravity, both of which may be considered as very nearly pure cr free from water; mixtures of these two liquids may be made in any proportions, and the resulting specific gravities ascertained ; from which we may be enabled to esti- mate the proportions of the two fluids in any specimen where no water is present. This operation, however, is more difficult than may be imagined. By taking ether and diluting it successively with equal portions of alcohol, the resulting specific gravities may be £820.] Mr. Dalton on Sulphuric Ether. 12] _ found in the usual way, provided we could guard against any loss of the mixture. But such is the evaporating power of ether, especially when pure, that it is impossible to pour it from one vessel into another in the open air without much loss. In one instance I found that after six successive dilutions and 12 trans- fers, made with great care, I had lost one-fifth of the whole weight used. Insuch case, if the diluting portions are not dimi- nished duly, the results must be erroneous. ®ne circumstance is favourable, the increase of density by chemical action appears to be very small; so that the densities may be calculated without very material error. The following table will afford a moderately good approximation, which may have its use till a better is made. Table of the Specific Gravities of Mixtures of Ether and Alcohol. Ether, Alcohol. Sp. Gr. 100 + . 0 yas Wide ks a a catulallgt ued e 0:720 “Ee PRemee | UR een mee MPT mE aR ey Fe Oe UR ote barat se ene 0°744 rake AAD ad carci bs GIs 0, die’ Sota eb eye 0°756 21 adi nea il cee, age ie! etl « 0-768 BU hat Be Mca tl'o “ot ase aA Sha lo, yeh Beales 0-780 Ds ART © Palen 98 RE OOPS > 2 0-792 Belen Edwin cision sieht icin» einige 0:804 20 + 80 aA ashte aide Gsnsies 5 shen 0-816 1 OE) aS. Sn S25 0°828 ML so aiad, wcl eka wo ic, ES 0°830 From this table it would seem that ether of the second quality, or that of the shops in general, contains about 25 per cent. of alcohol; and that of the third quality from 55 to 60 of alcohol ; and the proportion of this article will be still greater on the pro- bable supposition that pure alcohol is as low as 0:82 in specific gravity. So far we have considered the mixtures of ether and alcohol in their purest states, or nearly such ; and it has been observed that in the ordinary course of manufacture, it is these mixtures, only varied in proportion, that occur. But if we introduce water so as to vary the proportions of ether, alcohol, and water, indefi- nitely, then some new phenomena occur, and the quantity of ether in such mixtures is no longer to be determined by the specific gravities. These mixtures are in some proportions uniform throughout ; in others, they resolve into two fluids of different specific gravities, alike transparent and colvurless, but easily distinguishable from a filmy-like surface between the two fluids. Both the heavy and light, or as they may be called, the watery and ethery fluids, contain in all cases less or more of all the three ingredients. They seem to vary in their specific gra- vities according to this law; whenever the upper fluid is extremely light, the under one is extremely heavy; namely, 122 Mr. Dalton on Sulphuric Ether. [Fes. about 0°72 and 0:98 respectively ; and whenever the under fluid is extremely light, then the upper one is extremely heavy, but the two never approximate nearer than 0:93 and 0:82 respect- ively. As far as { have found, I am pretty well convinced that in this last case the heavy fluid is constituted of 1 atom of ether, 1 of alcohol, and 5 of water; and the light fluid of 1 ether, 1 alcohol, and | water, being a true ternary compound of the three elements. These facts are beautifully exhibited by a single experiment. Let equal volumes of pure ether and water be agitated together; on subsiding, the very heavy and very light fluids are immediately perceived ; let then pure alcohol be added by degrees, and agitated; it wil! be observed that both fluids have increased in volume upon each addition, till at length the upper fluid arrives at its maximum volume and specific gra- vity. A further addition of alcohol then diminishes the volume of ether till at length it disappears, and the whole becomes one uniform fluid. The boiling point of ether T find forms a curious part of its history ; I mean that point of temperature when its vapour is of sufficient force to balance the weight of the atmosphere. In my early experiments I found the point by immersing a thermometer in the boiling fluid, when it stood at 102°; but in subsequent experiments I used a barometer tube bent about one-third from the sealed end, and the legs laid parallel. A small portion of ether was let up to the sealed end, and the tube from thence to a little past the turn was filled with mercury. The instrument thus prepared was immersed in a tall jar of warm water till the vapour arose from the ether and depressed the mereury, which ascending in the other leg, was brought to a levelin the two. In this way, the same ether, in the temperature of 98°, exhibited a force equal to the atmosphere. Something like this I find takes place in alcohol of 0°83 specific gravity. It boils in a phial at 176°; but in a tube its vapour is equal to the atmosphere in a temperature of 172°. Pure ether of 0°72 specific gravity boils in the tube at 95° or 96°, as Gay-Lussac has observed ; but in a hial I find the thermometer may be raised to 98° in the boiling iquid. The boiling point of a mixture of pure ether and pure alcohol may be made to vary from 96° to 170°; but we cannot infer the boiling point from a knowledge of the proportions of the mixture ; it is always much nearer that of ether than the pro- portions would indicate. Indeed it is the same with alcohol and water, and all similar mixtures. A mixture of equal parts of alcohol and water boils at 183°; whereas by the rule of propor- tion it ought to boil at 194°. A mixture of four parts ether and three parts alcohol I found boiled at 117° in the tube, and 122° or 123° in the air, which by proportion should have boiled at 127°. It was of specific gravity 0°769, and might, therefore, be eonsidered as between the second and third quality. The modifications of the boiling point of ether produced by -1820.] _ Mr. Dalion on Sulphuric Ether. 123 water, however, are the most astonishing. The heavy fluid aris- ing from the washing of ether by water, which is of the specific ravity 0°96, and which consists of 8 or 10 parts of water and en 2 of ether and alcohol, boils at 103° in the tube ; but if the temperature be increased, it soon ceases to manifest the increas- ing progressive elasticity of pure ether, as may well be expected. The reason of this is pretty obvious ; water possesses little or no affinity for ether ; it yields readily the few atoms it possesses to the influence of heat, and when they are raised, the supply ceases. Hence we see the necessity of using a pure ether when the tension at various successive temperatures is to be found. Specific Gravity of Eiher Vapour. In 1803 and 1804 I made a great many experiments on the combustion of ether vapour mixed with oxygen gas by electricity. These sufficiently demonstrated the great specific gravity of this vapour, as it was sufficient to have four or five per cent. of volume of it to produce abundance of carbonic acid, and to require a greater abundance of oxygen. I found it expedient to ascertain as near as possible the exact specific gravity, and attempted it as follows in September, 1803. I took a balloon glass, of the capacity of 253 cubic inches, having a wide neck, to which was adapted a brass cap and stop- cock. Into this a graduated tube, =2,ths of an inch diameter, containing ether of 0°758 specific gravity, and a manometer were introduced ; the manometer was as usual a tube of th inch bore, closed at one end and duly graduated, with a globule of mercury sliding init. The vessel was immediately made air tight, and kept so for several days, during which time the pro- gress of the evaporation and of the gauge was occasionally noted. The temperature of the air in the room was usually about 55°; but as this was of no importance, it was not particu- dJarly noted. The cbservations follow : the ether tube was gradu- ated into water grain measures : barometer 30 inches. Mricmeter Measures of ether evaporated, Beaks 25") 2 plat.’ es PS: Ooo ey oh. age 0:0 5 —— ...... BOS). 4 alii 6°5 8 ——...... 858 . . 100— Be ae ea Hee B48 tA. 7 ee 16°5 9 ——...... BOO Aen ee 20°5 hal Pc 825 24-6 10 —— ...... Bp as ES 28°5 Ee We a BOOH saya 34-0 12 —— PORE Us MR 389 260°) p.m? POOR EL 42-0 — 9 ——...... FEOP 7s SOS 46°5 a0” POADNELTE..5. TTBS gare le 49°5 124 Mr. Dalton on Sulphuric Ether. [Fes. Now 49:5 measures of ether = 37:5 gr. and this quantity being by the manometer = 113 of the atmospheric pressure, we have 113 : 37:5 :: 772 : 256 gr. the weight of 253 cubic inches of ethereal vapour of atmospheric force ; but the weight of the’ same volume of common air = 77 gr. Hence ethereal vapour = 3:3 times the specific gravity of air. I find amongst my notes in 1805 a similar experiment, from which the specific gravity was deduced = 2°65 only. This difference occasioned me to repeat the experiment as follows : Balloon containing 404 Cubic Inches = 123 Gr. of Air. Barometer, 30 inches. Ether, 0°728 specific gravity in the temperature 48°. Measures of ether Manometer, ~ evaporated. 1819:={Beb,.25'<"- 10. ata”, 22 8100 he a: 0-0 (pia: 5.4 .S40B2Ay. 8-0— pz: 4040 BS 9°5 3 o— ADDS: . hoe eRe 11-:0— 54 —— .... 4000+...... 13°5 Reeve aed AOU Maes 15:0 9 KEEN BOGE HIS 17:0 96. dieprasm.| Oe eSO0S: oes ZOU 11+ BOO 2 aac 27-0— 2Aipims 42. SQ00— 6 oc 28-0 6 — PB Yo (0) ea aR Cy Pe 30°0 9 SOTO. SEARS oe 32:0 Dia HOP ak AEA 0 id CHRO QE PO 36:0 9 pom: 260. 3812). 5cake 39°0 At this period the cock was turned, and the air and vapour let out, till the equilibrium was restored with the atmosphere, the barometer being then 29-5 ; the thermometer was not noted. In a few minutes the cock was again turned, and the experiment continued. Measures of ether Manometer. evaporated. Feb. 27.02) putes fa. Fingal 0-0 28 2 —— ...... NL aoe a 5:5 Qe ee ln ADs cee 6 Che March 1 9 a.m OUT Melee ve ia 'e = 10°0 D > Pray erase GODO VC iieichs ie + 14-0 2 FO” S5I. ge teat S069 Seenu ts 15°5 aR RT ER AS SOG Petts. aes 18:0— So OW rat mena SOOT hee cc ae 19°5 Oe Pie owas so BONO ines nso 0s 22:0 SOOO Maat tense OOUO eee sciences CFU Dope et S800... . 25°0 1820.] Mr. Dalton on Sulphuric Ether. 125 sures of et Manometer, me sofether evaporated. March’ 5. 9s. asm. ni... ie HBOOD « weceaeense'O 6 9 ——...... BS fans sede OD) 9-2 eM. ee BOTA vcd bles 28:0 + MeO ei aelnas, Se BOT. ° iki For the last two days there was only a drop of fluid left at the bottom of the tube (nearly five inches deep) which seemed to be not evaporable ; but it was judged proper to continue the expe- riment in order to ascertain whether the vessel was perfectly air tight, and of course the gauge would continue stationary. The drop of fluid smelled of alcohcl, and when diluted and treated with muriate of barytes was milky. By making the calculation as above, the specific gravity of. ether vapour from the first part of the experiment comes out . 3°05, and from the last part, 3:2. The slow manner in which ether evaporates in these circumstances is surprising; in the latter part of the experiment it is to be ascribed to the depth of the surface of fluid in the tube, and the partly saturated air. Though convinced the above results were very good approxi- mations, | was desirous to have a confirmation of it by some more direct method. I took a bottle of the capacity of 2,600 gr. of water, and graduated accordingly ; this being filled up to 1,100 gr. with dry mercury was inverted in the mercurial trough with 1,500commonair. Through this mercury were passed 1, 2, 3, or more grains of ether, which expanded the air, and from the quantity of expansion, compared with the weight of ether let up, the specific gravity of the vapour was inferred. This method did not give uniform results owing to a considerable portion of such minute quantities of ether being entangled by the mercury in its passage. To remedy this, I took a small tube, one-seventh of an inch in diameter internally, and two inches long, which was sealed at one end, and then graduated into water grains, which was such as to allow nearly one-fourth of an inch for one grain. This was filled with mercury, except for one, two, or more grain measures, which were afterwards filled with ether, and the finger being applied, the tube was plunged into the mercury and passed through the neck of the bottle up to the surface of the mercury in the bottle. | In this way the ether was conveyed through the mercury without quitting the tube, and by gentle agitation was ejected and dissipated in vapour in a few minutes afterwards. The results in several experiments were nearly uniform, giving an increase of volume of gas from 255 to 275 grain measures for each grain of ether in weight. This gives the specific gravity of ether vapour from 3-1 to 3:3. On the whole, I think 3-1 is probably the nearest exoression in two places of figures that can be attained. \ 126 Mr. Dalton on Sulphuric Ether. [Fes. Elasticity of Ether Vapour, the same in Air and in a Vacuum. The same tension or elasticity of ether vapour takes place in air as ina vacuum,” just as with the steam of water and other liquids. But this is not true of impure ether, if it be made to pass through water into the air, because by this operation it is improved in quality, though greatly diminished in quantity. When the temperature of the air was 43°, and barometer 29°70, I passed up through water into a graduated tube contain- ing 51 grain measures of air, about three or four grains of 0°73 ether. The air was in a few minutes expanded to 74 measures ; and the ether barometer (that is, a barometer with the same kind of ether thrown up into the vacuum) stood at 20°5 in the same temperature ; hence we have oa x 51 —- x 51) = 74 nearly ; which accords with the before-mentioned theorem. The tube being afterwards immersed in water of 66° gave 104 mea- sures of vapourized gas; and in 70° gave 118 measures. It -stood for some months in water, still retaining a fluctuating volume of gas, according to the changes of barometer and ther- mometer; and at last the gas was passed through water, and instantly gave the original 51 measures of air. The quality of ether may be judged of from passing a small portion of it through water in a graduated tube. Thirty grain measures of the best ether (0°73) passed up a tube of eight inches long filled with water lost four or five gr. Thirty grains of another ether, consisting of a mixture of 15 ether (0°735) and 15 alcohol (0°85), when passed in like manner, only gave five measures of fluid ether, swimming on the surface of the water. Relation of Ether Vapour to Liquids. Gases vapourized by ether may be kept over dry mercury, and transferred through the same without loss. But they are not kept over water, alcohol, and other liquids, without loss of vapour, though this is variable according to the nature of the fluid and other circumstances. Alcohol absorbs ether vapour out of air much faster than water does. I filled two similarly graduated tubes with ether- ized air, and placed them over alcohol and water respectively : they lost vapour as under: Tube over alcohol, Tube over water. 155 measures. 116in 5 minutes. il2in 8 minutes. 104 in 30 minutes. 100 washed. 155 measures. 142 in 10 minutes. 138 in 13 minutes. 130 in 30 minutes. 100 washed. 1820.] Mr. Dalton on Sulphuric Ether. 127 The non-efficiency of water in abstracting ether vapour is further manifested by the following experiment. I took a tall graduated cylindric jar, of three inches diameter, into which 20 oz. measures of air were passed over water. Thirty grain measures of ether (0°73) were then passed up into the air, through a volume of five inches of water, which was of course diminished a little in its passage, and then spread over the surface of the water to the thickness of ~1~th of an inch nearly. The volume of air and vapour varied as under : ie MM. Oz. Se te ne ey Tan on OD BE ea ae ee a ag 291 SENN AN Voi oc s Mn atysve erase whey tats DOB Gt ys vale: bak ok siemael oe mee SEAN tian ae Liban. g eee Ben Oi Le ihc Ba, ate UE et wey DRE. =e GON otis aT Feed «8 . 28 ORR HoOSk CAR ino viaa e tet 1 Day..... gs Gnibtacs'n ga ee ‘Weeks sole he oc ke Washed. ........ 20° Here it is observable, the vaponr increased for half an hour, and then began to decline again, but slowly. It increased the volume by 84 oz. = 3,960 grain measures, which is equal to 15 gr. in weight by the preceding determination; but the ether weighed 22 gr.; so that a loss of one-third of the weight of the ether only was occasioned by the action of so great a surface of water on it for half an hour. Force of Ether Vepour. My former experiments on the force of ether having been made with an article not of the highest purity, they ought all to exhibit a force too /ow for the temperature. Such I find to be the fact; at least within a range of temperature of easy investi- gation, that is, from 30° to 140°. The difference, however, is but small, and may, without much error, be corrected by deduct- ing 2° or 3° from the respective temperatures, as given in my table. (New System of Chemistry, p. 14.) ‘The apparatus to be used, consists of a common barometer tube, one bent into a syphon at one-third of the length from the sealed end, and @ tall smaller one bent six or seven inches from the sealed end, and having the other leg 40 inches long. The first of these instruments is best used tor atmospheric temperatures, having a drop of ether Jet up into the vacuum. The second, is to have its short leg filed with mercury, and an inch of the other leg, a drop of ether being at the top of the mercury in the short leg. 128 Mr. Dalton on Sulphuric Ether. [Fes, This is used from temperature 80° to 110° or 120°. The third is to have its short leg filled with mercury, and a drop of ether as the other, and its long leg filled to various heights with mercury, according to the temperature. It may be advantageously used from 120° to 140°. For temperatures between 140° and 212°, I have always used a tube similar to the last mentioned, but hav- ing its upper-extremity sealed, and containing air of common den- sity over the mercurial column, and nearly equal in volume to the capacity of the other leg. When the ether vapour is formed in force, it condenses the said air, and from the condensation, the force is inferred by a well-known law. Having had some reason to suspect my former results by this instrument were somewhat too high; I have been induced to examine the defects to which this instrument is liable. The end of the tube must be drawn out to a point before sealing, and suffered to cool to the temperature of the air; after this, the end must be closed by the point of a flame, otherwise the.air in the tube may be rarefied by the heat, in which case the force of the steam will be overrated. Another cause of similar error is the existence of ether vapour in the air at the moment of sealing; this will happen if the tube is not carefully dried inside after the instru- ment is filled with mercury. In this case, the air in the tube is rarefied by the steam, and consequently is of an unknown but reduced density. The opposite error is liable to be induced, by the frequent use of the instrument. By the motion of the mercury, the small remains of ether mechanically mixed with it rises to the top, and a visible stratum of ether is thereby exposed to the air. In this case an addition of force is given to the air ; but as the quantity of this force is known for any temperature, it may be allowed for accordingly. I prefer, however, sealing the tube when well dried, and the air of atmospheric density at the time ; and if the ether appear to rise to the surface afterwards, the correction must be applied. In order to have a complete check upon this instrument, it should be adapted so as to be applicable at some temperature (as 140°), where the force is . known by other direct means. The error, if any, will thus be shown, and may be calculated for other temperatures. I have lately made, for the first time, various experiments on the force of steam from water, in temperatures from 212° to 300°; the results which convince me that the theoretic forces which I gave in the fifth volume of the Memoirs, as also those subsequently in my Chemistry, are both erroneous; the former being about as much too small as the latter are too large, so that the mean of the two series is a near approximation to the truth. Experiments on the force of aqueous steam in high tempera- tures have been lately made by Mr. Southern, of the Soho, Birmingham,* and by Dr. Ure, of Glasgow,+ the results of # Dr. Robison’s Works by Dr. Brewster. + It would hayegiven me great pli asure to have been able to adduce Dr, Use’s 1820.] - Mr. Dalton on Sulphuric Ether. 129 _ which agree very well with each other, and with the mean of my two theoretic tables. As for the force of steam below 212°, no one has found any material variation from those in my first table ; indeed scarcely any one seems to have attended much to - those below 100°, which [ was most anxious to have correct. The force of steam at 32° is an important element ; I have spent ‘much time and labour upon it, both before and since my first table was published ; it 1s not less, I think, than 0-2 of an inch, nor more than 0:3; these being the extremes of my experiments ; perhaps 0:25 is very near the truth. My table of the force of alcoholic vapour represents it too high for temperatures below 60°, and for those above rather too low. These errors arose partly from the alcohol not being free from water, and partly from a mistake, as I now apprehend, in fixing a standard mark on the alcohol barometer. They are but small, and of little importance, as the cbservations were not used in establishing general principles. An improved and more extended series of observations on the force of alcohol vapour has recently been published by Dr. Ure, as mentioned above, the results of which fall in as well as can be desired with those from water, in establishing a general law that the vapours of homoge- neous liquids expand in geometrical progression to equal inter- vals, or at least to the same intervals of temperature. 1 may add, my own experiments recently made for the first time, corrobo- rate those of Dr. Ure in the interval of temperature from 175° ta 212°.* The following skeleton of a table of the force of vapour from water, alcohol, and ether, is formed from what I consider as the most correct experiments hitherto made on these subjects, and may have its use, though it will be found not to differ very mate- ety from my former tables, except where they differ from each other. experiments on ether also, in corroboration of my early experiments, and of the general principles thence derived ; a stronger condemnation of those principles could not have been brought forward than their agreement with the results of Dr, Ure onether vapour. All the information we have given as to the quality, &c. of his ether is contained in the following paragraph. ‘ The ether of the shops, as prepared by the eminent London apothecaries, boils generally at L12°; but when washed with water or redistilled, it boils at 104° or 105°. 1t may by rectification, however, be made to boil at astill lewer temperature.” We are presented with ‘two series of experiments on the force of ether vapour ; the first beginsat 34° with the force 6-2, and ends at 104°, with the force of 30 inches of mercury; the second begins at 105° with the same force, and ends at 210° with the force of 166 inches. What the specific gravities of the two kinds of ether used were, and whether the ethers used were obtained from the very inferior ether of (12° by washing, or by distillation, are important points, concerning which we are not informed. How- ever, Dr. Ure contrives to blend these two disjointed series, and to compare the results with those of mine made upon ether which boiled at 98°; aud finding great discrepances, he concludes my results on ether and principles deduced from them are pregnant with errors, * Philosophical Transactions, 1818, Vor. XV. N° II, I 130 Mr. Dalton on Sulphuric Ether. [Fes. Table of the Forces of Aqueous, Alcoholic, and Ethereal Vapours. Temperatures |Aqueous vapour. Ra-|Alcohol vapour. Ra-jEthereal vapour, (common scale). tio, 2°6. tio, 2°T. Ratio, 2. 36° 0°29 in. 0°56 in. 7°5 in. 64> som, 151 15-0 96 1-95 4-07 (f) 30-0 - 132 507 (a) | 11-00(g) 60-0 173 13°18 (6) 29-70 (h) 120-0 220 34-20 (c) 80:20 (2) 240-0 272 88:90 (d) a a: 340(e) | 231-00 = ne Dr. Ure’s numbers for ether corresponding to the above, the last exclusive, are 6°55, 13, 25°7, 49°8 [49], 96°4; the ratio is of course less than two, and a descending one ; namely, 1-98, 1:97, 1-94, and 1:93; this last circumstance characterizes a mixed liquid. I have not extended the experiments on ether further than 212°; but as that temperature gives a force of 207 or 209, I esti- mate the force to be 240 at 220° nearly. If the forces registered in the preceding table be allowed as near approximations to the truth, it must, [ think, be admitted that they increase in geometrical progression to the same inter- vals of temperature for a range of 200° at least. Whether those intervals of temperature are equal one to another successively is another inquiry, which the above facts and observations do not enable us to decide. Analysis of Ether by Electricity, &c. When a little fiuid ether is let up into Volta’s eudiometer, either over mercury or water, and a small portion of azotic gas is likewise sent up, in order to be vapourized by the ether ; then if the vapourized air be electrified for an hour, some permanent gas is produced, and charcoal is precipitated. The gas when washed is chiefly or wholly carburetted hydrogen ; for it takes two volumes of oxygen, and yields one of carbonic acid gas. If the vapourized gas be dry and over mercury, a volume of vapour yields two volumes of carburetted hydrogen, and moisture is perceived within the tube. Ifthe electrification were continued. (a) Southern, 4:71. Ure, 4°70 (4) Southern, 13-00. Ure, 12-95. {c) Southern, 35:20, Ure, 35°50. (d) Southern, 88°00+. Ure, 89-00. 90. The mean of my two tables. (e) This observationis Mr. Southern’s. There is reason to suspect his tempera- tures too high for his forcesin the high pressures. They exceed Dr, Ure'’s, (f) Ure, 4°02. (z) Ure, 11-20. (i) Ure, 30-00. {i) Ure, 78:50, Bettan, 82. 1820.] Mr. Dalton on Sulphuric Ether. 131 no doubt the volume of gas would be greatly increased, and end in pure hydrogen mixed with azote. These experiments are not decisive ; but they evidently point out the composition of the atom of ether to be 1 carburetted hydrogen, | charcoal, and 1 water, or 2 olefiant gas, and 1 water. The best method of analysis is by firing the vapour of ether mixed with oxygen gas in Volta’s eudiometer. This method I discovered in September, 1803, and have used it occasionally ever since. It may be proper to describe the various modifica~ tions of which this process is spisceptible. When a few drops of ether are passed through water into the eudiometer containing oxygen gas, the volume of the gas is in a few minutes enlarged more or less, according to the temperature. In temperatures from 60° to 70°, the volume is about doubled; but below those it is less than doubled; and above more than doubled, agreeably to the principle before explained. (a) If the air be doubled or more, and an electric spark be taken in it, the probability is, that no explosion will ensue; ifby repeated sparking an explosion take place, it is feeble, and may be repeated a few seconds afterwards, sometimes once or twice. The residue of gas being examined is found to contain a little carbonic acid, some new combustible gas, and oxygen in various proportions. In short, the operation is very incomplete, owing to an excess of ether vapour. ; (b) If the oxygen gas be good, and the volume be increased from 100 to 150 by the vapour (which will naturally arise m temperatures between 40° and 50°, and in higher temperatures the volume may be reduced by cautious agitation, till the water has absorbed part of the superfluous ether and vapour), then a spark produces a violent explosion. The gaseous volume is doubled, or from 150 becomes 300; and upon examination is found to consist of carbonic acid and new combustible gas, but chiefly the latter. Little or no oxygen is found. If the ether vapour be only from 5 to 10 per cent. of the volume of oxygen, the explosion is vigorous, and a complete combustion takes place. The residue consists of carbonic acid and oxygen gases only. Ten volumes of ether vapour require about 60 of oxygen, and produee about 40 of carbonic acid. (c) If 100 oxygen be increased by ether vapour to 120 or 130, a violent explosion ensues, and the whole of the vapour is con- verted into carbonic acid, water, and new combustible gas ; a little charcoal is sometimes deposited, so as to make the air muddy at the instant after explosion; no oxygen is found in the residue. (d) The combustion of ether vapour may be effected by com- mon air as well as by oxygen gas, only the proportion of vapour to air is very small and limited. If the vapour exceed five per cent. it will not fire ; and if it fall short of two per cent. it rarely fires. The coibustion is attended with the production of new combustible gas, or otherwise complete, according to the ¥2 132 Mr. Dalton on Sulphuric Ether. [Fes. greater or less proportion of vapour, as is the case with oxygen gas. In respect to the new combustible gas in the above paragraph, its nature may be ascertained by abstracting the carbonic acid in the usual way, and then exploding it with oxygen. In the para- graph (a), the new gas is often nearly pure carburetted hydrogen; but in (c) and (d) it is always a mixture of carbonic oxide and hydrogen in nearly equal volumes ; as is proved from its requir- ing 50 per cert. of oxygen, and producing 50 per cent. of carbonic acid. In (6) it is chiefly these two gases, but has a little carburetted hydrogen occasionally mixed with them. When a certain volume of ether vapour is completely burned at one operation, or itis partially burned at the first, as in (a), (0), (c), and (d), and the combustion finished by a second operation, still the same yolume of vapour requires the same volume of oxygen for its complete combustion, and produces the same volume of carbonic acid. And it is always found that the car- bonic acid contains two-thirds of the oxygen spent, and conse- quently the hydrogen engages one-third of the oxygen to form ‘water. Hence it appears that the combustible element of ether is olefiant gas; but as there,is reason to conclude that oxygen is one of the elements of ether, it must be combined with hydrogen; so that water must be the incombustible element. In order to find what number of atoms of water and olefiant gas must be combined to form one of ether, we must have regard to the weights of the different elements which combine. Now, from the experiments above related, it appears that one measure of ether vapour (weighing 3-1) requires six measures of oxygen gas (weighing 6:6); but two atoms of olefiant gas weigh 12°8, and one of water weighs 8, making together 20-8, which would require six atoms of oxygen, weighing 42, for their combustion ; ‘that is, such compound atom would require rather more than double its weight of oxygen, which is the proportion I find by experiment for ether vapour. Hence then we may conclude, that the atom of ether weighs 20-8, and is compounded of one atom of water and two of olefiant gas. j In January, 1809, I made an experiment on the slow combus- tion of ether in a lamp, in a large balloon glass. The capacity of the balloon was two cubic feet; hence the oxygen of the common air in it would weigh 250 gr. nearly. A small lamp with ether was lighted, and instantly dropped into the balloon, which was immediately closed. The lamp burmed till it was extinguished for want of air. After a few minutes it was taken out, and the loss of weight ascertained to be 31 gr.. The resi- duary gas being examined was found to contain 16 per cent. oxygen, and 3 or 4 carbonic acid; but in order to obtain the carbonic acid more accurately, the whole volume of air was subjected to lime water, in such manner that all the air which came out was agitated in the lime water that entered the balloon. The quantity of lime water requisite to saturate the carbonic 1820.] Mr. Dalton on Sulphuric Ether. 133 acid was as much as saturated 107 gr. in weight of dry sulphuric acid = 60 gr. of carbonic acid = 17 charcoal + 45 oxygen. But the oxygen spent in the combustion was > of 250 gr. = 60 gr. nearly, of which we &nd two-thirds, or rather more, in the carbonic acid produced ; the rest must have combined with | the hydrogen. And the ether consumed was rather more than one-half of the weight of the oxygen, which may well be sup- posed to arise from alittle loss by evaporation. This experiment, therefore, corroborates the conclusion above obtained. My first idea of the ether atom, published in the table on thé absorption of gases’ by water in 1803,* was two atoms of carbon, and one of hydrogen. This incorrect notion was formed from some of my early experiments combined with the analysis given by cthers. M. Saussure, in his last essay on ether, has deter- mined its proportions as under; which, being compared with mine, are found to differ from them materially. Saussure’s. Mine. ar bom Hs. Hie ss oe O98 S854 es 51:9 RN wee nia poem dintnan PID2 ee ees oo'7 Hydrogen .......... PHD! | caiessets nie 14-4 100-00 100-0 In the present essay I have alluded to the weight of an atom of alcohol; but this weight is not that given in my Chemistry, . Part £. From recent experiments on the combustion of alcoho- lic vapour in oxygen by electricity, as well as from the combus- tion of alcohol by the platina wire lamp without flame, I believe-- the alcohol of 0°82 specific gravity is constituted of one atom~ carburetted hydrogen and one of water, as it seems to give carbonic acid = half the volume of oxygen consumed, or very: little more. But there is a remarkable difference in the results when alcohol is burned in a lampin common air. This combus- tion gives carbonic acid nearly = two-thirds of the volume of oxygen, and would imply alcohol to be one water and one olefiant gas. At present I have not leisure to clear up this difficulty. ARTICLE VI. Calculations of Solar Eelipse to take plac 7 ke place on Sept. 7, 1820 By Col. Beaufoy, F.R.S. ais (To Dr. Thomson.) MY DEAR SIR, Bushey Heath, Jan, 6, 1820. Tue annular eclipse which takes place the 7th of next Sep- tember will naturally engage the attention of Europe; and it * Memvirs, vol. i, (Second Series,) 134 Col. Beaufoy’s Calculations of the Annular Eclipse. [FEx. being desirable to have corresponding observations on so rare a phenomenon, I have, with the hope of directing the view of others towards this object, sent you my calculations of the parti- cular appearances at this place, as well as the principal appear- ances in other parts of the world. By a mean of several observations of the circumpolar stars, made with an excellent circular instrument, two feet in diameter, and constructed by Mr. Cary, [ find the latitude of my Observatory to be 51°37’ 44-27” N. and longitude W. in time, 1’ 20:93” instead of 51° 37’ 42”, and 1’ 20-7” as shown hy Hadley’s sextant, and an artificial quicksilver horizon. I remain, my dear Sir, \ Yours very truly, Mark Brauroy. —— 5S 54 PM 2 21 34:5 44 18 50 1s. 39" 3 2 16; a Pe 2 31 345 40 56 35 16: 29 31 £E 3? 3ST.) Soe PIMs 2 Al 345 eStats 10 19 5b. 07 = &E 4 90 59 P.M. 2 51 345 34 15 10 24 10 46 E 4 28 17 P.M. 3 OL 34:5 30 Al 57 30 45 33 E SP OSF Si" Pee. 3 09 00:0 27 Ol. 21 45 49 20 E Grae Vt. BOM Duration of the central eclipse, 2" 14” 51”. By examining Pinkerton’s Modern Ailas, the following places are found nearest the moon’s tract. Latitude. Longitude. 81° 35’ 491489 50! 36’ W| Falls within the polar circle. 80 36 48 | 32 3T 19 _ |Falls also within the polar circle. 73 38 53.) 12 45 57 Falls over the north-east co.st of Greenland. 68 05 46; 5 Ol 31 Falls over theNorthSea; nearly due N.of Cape Wrath, N. B. Ga 196s") > 0» -1963 Falls over ditto, due N. of the Shetland Isles. 59 00 50} 3 O9 24 E |Falls over ditto, due B. of the Orkney Islands. 55 02 09 | 6 00 OT Falls over ditto, due E, of Newcastle-on-Tyne. 51 18 OO 8 35 55 Falls over Eversberg, a town of the Lower Rhine, : in Germany. AT 44 40); 11 04 52 ~~ |Falls nearly over the town of Weiiheim, in Bavaria. 44 18 50) 13 39 37 _ |Falls over the Adriatic Sea, alittle to the S. E. of Pravenna, 40 56 35|16 29 31 Falls nearly over the town of Altamuca in the terri- ’ tory of Barri, the kingdom of Naples, 37 37 10)19 51 O7 Falls over the Louian Sea, W. of the Gulf of Arcadia, in the Morea. 34 15 10} 24 10 46 |Falls over the Mediterranean to the S. of Candia, 30 41 54) 30 45 33 Falls over a spotnearly W, of the town of Zaera, in L. Egypt. 27 O1 21) 45 49 20 Falls ae the district of Ared, in the Arabia Deserta, 136 Analyses of Books. [Frs. ArticLe VII. ANALYSES OF Books. Memoirs of the Literary and Philosophical Society of Manchester, Second Series. Vol. L1I.1819. Tuis volume of 512 pages contains 24 papers : I. Experiments and Observations on Phosphoric Acid, and on the Salis denominated Phosphates. By John Dalton.—This paper was read to the Society in the beginning of 1813, a cir- cumstance which must not be forgotten while taking a view of its contents. ‘Since that time experiments have been made on the subject by Berzelius, Dulong, Davy, and myself. Of every thing brought to light by these experiments, Mr. Dalton must have beenignorant when his paper was printed, or at least when it was read ; for in a note at the end of his paper (dated Oct. 1817), he notices the labours of Berzelius, Dulong, and myself ; but still adheres to the opinions given in his paper. This being” the case, I think it needless to enter into any controversial dis- cussion. I shail, therefore, just give an account of Mr. Dalton’s opinions, and, for my own, refer the reader to my review of the Philosophical Transactions for 1818, and to the chapter in my System of Chemistry, in which I give an account of the phosphates. Mr. Dalton conceives that phosphoric acid might be obtained at a much cheaper rate from the earth of bones than by treating Snlepeyh with nitric acid. There is no doubt of this. But he as not given any process by which such an extrication can be accomplished. ‘The following would probably answer: Saturate the quadriphosphate of lime, which remains after the earth of bones has been decomposed by sulphuric acid, with ammonia ; filter ; evaporate the solution to dryness ; and expose the dry salt to a red heat. Pure phosphoric acid will remain behind. This process will cost a quantity of sulphuric acid nearly equal to the weight of the earth of bones employed. The quantity of carbonate of ammonia requisite to saturate the acid will be at Jeast equal to double the weight of the earth of bones. Mr. Dalton finds the composition of earth of bones as follows = CarbOmieraGid inn cman sche viel. c 3 Bimmer Ga, 2 ee 2 meee Wl Phosphate of lime . BORNE ou 86 100 He thinks that 81 parts of concentrated sulphuric acid will be necessary to decompose 10 parts of earth of bones. The acid product obtained is either an octophosphate or dodecaphosphate, 1820.] Memoirs of the Literary Society of Manchester. 137 he is not sure which. On the first supposition, it is com- posed of URS cae sp etatle Aelate &,0,= 6 1as0y0 tae 881 REETLOES § niu ae pivtalolainiehiysint vr isrsteio ii. 100 On the second, eat orcs ae nates sete 92 Dime. Van is o cteraPatolchelthe tls fo. 8 100 According to the relative weights of the atoms of lime and phosphoric acid, the former of these numbers would indicate a hexaphosphate ; the second an ennea phosphate ; but in none of my experiments, which were very much varied, did I meet with any such compounds. Mr. Dalton considers the phosphate of lime in the earth of bones as composed of nearly equal weights of acid and base. He recognised two phosphates of soda, the phosphate and biphosphate, as had been done by chemists long before his time. From the number which he has pitched on to denote the weight of an atom of soda, he distinguishes these salts by the names of biphosphate and quadriphosphate. The following table gives Mr. Dalton’s analysis of some other phosphates : Acid. Phosphate of barytes ........ 100 + 297 barytes. Phosphate of strontian. ...... 100 + 200 strontian. Phosphate of magnesia. ...... 100 + 70 magnesia. Phosphate of alumina........ 100 + 64 alumina. Mr. Dalton observes, and thinks the observation new, that nitric and muriatic acid decompose phosphate of lime, as well as sulphuric acid. I will just remind him of one fact. In the original process proposed by Scheele for extracting phosphorus from bones, the first step was to decompose the phosphate of lime by means of nitric acid. Il. Experiments and Observations on the Combinations of Carbonic Acid and Ammonia. By John Dalton.—This paper was also read in 1813. He begins it by giving an account of the change which carbonate of ammonia undergoes when exposed to the air. One half of the ammonia gradually flies off, and leaves a bicarbonate of ammonia comparatively fixed, and nearly destitute of smell. I had given an account of this change in the last edition of my System of Chemistry, from my own experiments, which had been made before 1813. I presume the fact was known to other chemists. When I mentioned it to Dr. Wollaston and to Dr. Marcet, I found they were both aware of it. I mention this to show the disadvantage of publishing 138 Analyses of Books. [Frs. chemical papers so many years after they have been read. In 1813, Mr. Dalton, I believe, had he printed his paper, would scarcely have been anticipated in any publication ; though I have mentioned three persons who were aware of the facts at least as early. Mr. Dalton is not disposed to give credit to Gay-Lussac’s assertion that one volume carbonic acid gas and two volumes of ammonia condense each other into solid carbonate ; but I can give my testimony to the accuracy of this fact, which indeed I have had occasion to repeat more than once. If you mix one volume of ammonia and one volume of carbonic acid gas toge- ther, or two volumes of ammonia and one volume of carbonic acid gas, in either case you get a dry solid salt. The first is a bicarbonate, the second a carbonate ; for what Mr. Dalton calls a carbonate, I consider to be a bicarbonate ; while his subcar- bonate I consider as a carbonate. Mr. Dalton conceives that other carbonates of ammonia exist besides these, and has given his reasons for believing in the existence of a subtricarbonate. It may be true that such a salt exists; but his reasons are not sufficient to establish the fact. IL1, Memoirs of the late Charles White, Esq. £.R.S. &c. with Reference to his professional Life and Writings. By Thomas Henry, F.R.S. &c.—Mr, White was for many years one of the most celebrated surgeons, and possessed one of the most exten- sive practices in the north of England. He was born in Man- chester on Oct. 4, 1728. His father, Dr. Thomas White, was an eminent practitioner of the. different branches of medicine, especially of surgery and midwifery. Mr. Charles White was educated in Manchester under the Rev. Mr. Russel, a respect- able clergyman, a good scholar, and a polite and well-bred gentleman. The pupil made a fair progress in classical learning, and at a very early age was taken under his father’s professional tuition. In this situation he soon evinced great activity and talent, and: began, when almost a boy, to practise in a line which was then generally confided to men of mature age. This early introduction laid the foundation, and, perhaps, was a principal cause of the high character. which Mr. White afterwards acquired in that department of the medical profession. In due time ke was sent to attend lectures and hospital prac- tice in London. Here he had for a fellow student Mr. John Hunter, who became afterwards so celebrated as a surgeon and a lecturer, while attending the lectures of Dr. William Hunter. Here they contracted a friendship which lasted for life. During his residence in London, Mr. White devoted his time most dili- ently to professional objects, scarcely allowing himself any time for amusement. He afterwards passed a winter at Edinburgh, at a time when that University was rapidly rising into reputation as a school of medicine. Having availed himself to the utmost extent of these opportu- 1820.] Memoirs of the Literary Society of Manchester. 139 nities of professional improvement, Mr. White joined his father, and soon became an eminent practitioner in his native town. When the Manchester Infirmary was established in 1752, he was appointed the surgeon to that important Institution, and he continued to fill that station till a few years before his death. During the early part of the last century, the art of midwifery was not so generally practised by males as at present, and the female midwifes were too often extremely ignorant, and were under the dominion of inyeterate prejudices. The injurious effects of these deficiencies were more felt in the subsequent treatment of puerperal women than during the time of labour. The lying-in woman was not allowed to rise from her bed before the ninth day ; the curtains were drawn around her ; the doors and windows were closed; every avenue to the external air was stopped ; and a large fire was kept up in the room. She was ~ loaded with blankets, and crammed with caudle, cordials, and broth. The frequent effects of this absurd treatment were puer- peral and miliary fevers. Mr. White set himself in opposition to usages so fatal in their consequences, and by great perseverance, a manly spirit, united with great professional ability, and the possession of the public confidence, he was fortunate enough to be ultimately able to accomplish his object. His patients were allowed to rise on the second day; the room was well ventilated, and kept cool; and no cordials or vinous liquors were allowed, except when absolutely necessary, and under proper restrictions. The good effects of these changes were so evident as to carry conviction wherever they were introduced. The miliary fever almost entirely disappeared, and the puerperal soon became comparatively of rare occurrence. __ Mr. White was chosen a member of the Royal Society in 1761. On the original institution of the Literary and Philosophical Society of Manchester, he was appointed one of the vice-presi- dents, an office which he continued almost to the period of his death. In 1803 he was seized with ophthalmia, and suffered long and severe pain in his left eye. The inflammation was subdued, but the sight of the eye was permanently injured. In 1812 the right eye became diseased, a total loss of vision ensued, and his general health rapidly declined. At length, on Feb. 20, 1813, when in the 85th year of his age, he finished a long life of unre- mitting exertion, and of great and extensive usefulness. vie The following is a list of his writings : In the Phil. Trans. are inserted the following papers: 1. An Account of the Topical Application of the Spunge in the Stoppage of Hemorrhages; 1772. This practice was afterwards super- seded by the invention of the tentaculum, for which surgery is indebted to Mr. Bromfield. 2. An Account of a remarkable Operation on a broken Arm; 1760. 3. An Account of a com- a Luxation of the Thigh-Bone of an Adult by external idlence ; 1766. 140 Analyses of Books. [Frs. His papers in the Memoirs of the Literary and Philosophical Society of Manchester are the following: 1. On the Regenera- tion of Animal Substances. 2. On the Natural History of the Cow so far as is relative to her giving Milk, particularly for the Use of Man; both in vol. 1, first series. 3. Observations on a Thigh-Bone of uncommon Length;,in vol. ii. 4. An Account of three different Kinds of Trees which are likely to prove a great Acquisition to this Kingdom, both in Point of Profit, and as Trees for Ornament and Shade ; in vol. v. He published likewise three separate works ; namely, 1. Cases in Surgery. 2. A Treatise qn.the Management of Pregnant and Lying-in Women. 3. An Essay on the Gradation in Man, and different Animals. I must here notice a remark of the author of this biographical account that it may not give occasion to too hasty a generaliza- tion. ‘‘The town of Manchester,” he observes, “ (the spring water of which contains much calcareous earth) and the sur- rounding country, afford very few cases of stone; but it is ‘remarkable that those parts of Yorkshire where the water is most free from calcareous impregnation are extremely productive of this terrible disease.” It might be inferred from this that pure water had rather a tendency to occasion calculous diseases. But it ought to be attended to that it is very seldom indeed that carbonate of lime or sulphate of lime are found in calculi; yet these are the calcareous salts which existin waters. Phosphate of lime, which is the most abundant saline constituent of calculi, exists in bread, and in every kind of animal food. Hence it is rather the food than the water that gives a tendency to this terrible disease. Glasgow was for many years very ill supplied with water. Most of the wells yielded only hard water, and the disease alluded to was fully as uncommon in Glasgow as about Manchester. About 10 years ago two water companies were established in Glasgow, and the city supplied with remarkably pure water (it contains only _,1,,th part of foreign bodies) from the Clyde; yet no tendency towards an increase of this disease has been observed. IV. Remarks tending to facilitate the Analysis of Spring and River Waters. By John Dalton. The object of this paper is to give some rules by which per- sons but little conversant with chemistry may be enabled to ascertain the goodness of the water with which they are supplied for the purposes of domestic economy or of manufactures. It contains an enumeration of the most common tests, with direc- tions how to use them. The object of the author is laudable ; but I suspect that after all the simplification that has been intro- duced into the mode of analyzing waters, still, in order to draw the proper inferences from experiment, a good deal of practice and considerable knowledge are requisite. Any body indeed may apply a few tests, and by their means draw a few obvious infer- — 1820.] Memoirs of the Literary Society of Manchesier. 141 ences respecting the foreign substances present in the water under examination. If it becomes milky with lime water, he infers carbonic acid or bicarbonate of lime ; if it is precipitated white by oxalate of ammonia, he infers the presence of a salt of lime. Muriate of barytes indicates sulphuric acid, and nitrate of silver muriatic acid. But to determine the quantities of the bodies present in water is much more difficult. I doubt whether Mr. Dalton’s methods be susceptible of much. precision. It is very difficult to determine the exact point of neutralization in very dilute solutions ; nor do I believe that the exact quantities of the liquids employed can be determined by measure. Weight seems the only accurate method. Mr. Dalton expresses his surprise at finding that lime, though supersaturated with carbonic acid, still acts as an alkali on vegetable colours. A little consi- deration will solve this difficulty. Suppose we dip into a solution of bicarbonate of lime a bit of litmus paper previously reddened by vinegar. The paper owes its red colour to the presence of acetic acid. ‘This acid is capable of displacing carbonic acid from all bases, and uniting with these bases in its place. When the paper is dipped into the liquid, the acetic acid leaves the litmus to unite with the lime; and if a sufficient quantity of lime be present, the paper must resume its blue colour; that is to say, lime must always act as an alkali when it is combined with a weaker acid than that which disguises the vegetable blue colour. There is no difficulty then in seeing the reason of the fact which surprised Mr. Dalton so much. V. Account of the Floating Island in Derwent Lake, Keswick. By Mr. Jonathan Otley.—The name of Floating Island is given to a portion of earth, about six feet in thickness, which rises occasionally in the south-east corner of the lake, not far from Lowdore, generally about 150 yards from the shore. It is attached by one side to the bottom, and sometimes extends to the length of above an acre, and sometimes constitutes only a few perches. Its rise is only at uncertain intervals. Sometimes it appears in two successive seasons, and sometimes not during an interval of seven or eight years. Sometimes it rises a foot above the surface of the lake, and sometimes remains several feet below that surface. It usually rises to the surface at the end of a warm dryseason. The bottom of this lake seems to consist of an imperfect kind of peat moss; and Mr. Otley suggests that part of the bottom is occasionally buoyed up to the surface in consequence of the great quantity of gas that is cenerated within it. Mr, Otley and Mr. Dalton collected a quantity of this gas in 1815. Mr. Dalton found it a mixture of nearly equal volumes of carburetted hydrogen and azotic gases with about six per cent. of carbonic acid gas. No oxygen could be detected in it. This absence of oxygen I think remarkable. I have found common air always mixed with the specimens of carburetted hydrogen gas collected from stagnant water-pools, (To be continued.) 142 Proceedings of Philosophical Societies. [Frs. Arricie VIII. Proceedings of Philosophical Socteties. ROYAL SOCIETY. Jan. 13, 1820.—Mr.-Herschell’s paper “ On the Action of Crystallized Bodies on Homogeneous Light, and on the Causes of the Deviation from Newton’s Scale of Tints which many of them develope on Exposure to a polarized Ray ” was concluded. When Malus published on the present subjeet, the number of doubly refracting crystals known to philosophers. was very limited ; and as the most remarkable of these possessed only one axis of double refraction, it was presumed that Huygen’s law applicable to that one might hold good im all. But the discovery of crystals with two axes of double refraction has shown the fallacy of this generalization, and rendered new investigations necessary. The author proceeded to observe that there are two modes of conducting observations on double refraction and pola- rization ; the one is founded on the immediate observation of the angular deviation of the extraordinary pencil; the other depends upon the separation of a polarized ray into comple- mentary portions by the action of crystallized lamine. ‘The author preferred the latter method, and after pointing out its advantages, observed, that to render observations on the tints developed by polarized light available, they must be capable of being compared with one another; hence the importance of knowing the existence, and tracing the laws of those causes which operate to disturb their regularity. In the author’s first inquiries on the polarization of light, he was struck by the great deviation from the succession of colours im thin lamine, as observed by Newton, that many crystals exhibited when cut into plates perpendicular to one of their axes; and finding this phenomenon unconnected with irregularities in their thickness or polish, and uniformly repeated in different and perfect speci- mens, he was led to inquire into their causes, especially as they appeared to form an unanswerable objection to M. Biot’s theory, which perfectly explains the tints in crystals with one axis. In the several sections of this elaborate paper, the author entered into a detailed description of the phenomena, which are reducible to one general fact, viz. that the axes of double refrac- tion differ in their position in the same crystal for the differently coloured rays of the spectrum, being dispersed in one plane over an angle more or less considerable according to the nature of the substance. In many bodies, the magnitude of this dispersion of the axes is comparatively small, while in others not remarkable for a high ordinary or extraordinary dispersive power, it 1s very great, and renders all computations of the tints in which it is not taken into account compietely erroneous. A new element is thus developed, which the author observed must in future enter 1820.) Royal Geological Society of Cornwall. 143 into all rigorous formule of double refraction; and another striking instance is presented of the inherent distinction between the different coloured molecules of light. At the same time, continued the author, by the complete explanation this principle affords of all the more perplexing anomalies in the tints, the theory of oscillation stands relieved of every difficulty, and may be received as adequate to the representation of all the pheno- mena of the polarized rays, and entitled to rank with the fits of easy transmission and reflection as a general and simple physical law. At this meeting a paper, by Dr. Granville, was read, entitled « An Account of a Case of Ovario-gestation.” The subject of this case having died suddenly, and under circumstances, rather peculiar, an examination of the body was instituted to discover the cause of her decease. On opening the abdomen a quantity of blood was found, and a tumour about four times the size of a hen’s egg obstructed the view of the internal parts of generation. This tumour rested on the left portion of the uterus, and upon examination was found to be connected with the left ovarium. At the inferior part of this tumour diaphanous membranes, includ- ing the rudiments of a fcetus of about four months’ growth, were observed. Upon further examinaticn, it was found that the ovarium where it enveloped the placenta had been ruptured by the growth of the foetus, and to the loss of blood thus occasioned the death of the mother was attributed. The uterus was consi- derably developed; the right ovarium was healthy; the left fallopian tube was also sound, and unattached to the tumour. The different stages of the dissection were illustrated by beauti- ful drawings made by Mr. Bauer. Jan. 20.—A paper, by Edmund Davy, Esq. was begun, enti- titled “‘ On some new Combinations of Platinum.” ROYAL GEOLOGICALSOCIETY OF CORNWALL. Siath Annual Report of the Council_—The state of compara- tive maturity to which the Society has now arrived affords less interesting matter for remark than during its early progress. The Council, therefore, in discharging this their annual duty to the members, have little left them to do but to call their atten- tion to the respectable rank which the Institution has attained, and to urge the necessity of their continued patronage to insure its stability. Independently of the intrinsic advantages of an Institution of this kind in gradually adding, by the labours of its members, to the knowledge of the physical structure of Cornwall, it possesses a secondary value by attracting to this part of the county indi- viduals eminent for their genius and _ scientific acquirements, whose presence cannot fail to be useful to any place which they visit. Owing to expenses incidental to the completion of a new 144 Proceedings of Philosophical Societies. = [Fer. museum, the funds of the Society have not, as was expected, as yet justified the addition, by purchase of any new minerals to the cabinet; neither have the donations been so numerous and splendid as last year. The Society has, however, been favoured with not a few specimens, as well from members as others. The communications on geology and the branches of science connected with it have been numerous and valuable, and the quantity of information contained in several of these respecting the structure of the county and its mineral repositories, renders it the duty of the Council to lay them before the public as soon as materials for a second volume are accumulated, a period probably at no great distance. The Council regret that the backwardness of many of the members who have it most in their power to forward some of the most interesting objects of the Institution, justifies, and indeed renders necessary, the repetition of the following appeal to their liberality and zeal. “The Council cannot avoid expressing their regret that so few new specimens have been obtained from the county mines ; and that consequently the department of the cabinet set apart for the reception of indigenous ores, which ought to be particularly rich and splendid, continues to be defective, and is eclipsed by many other collections, as well public as private; a circumstance uniformly exciting the surprise of strangers. “The Councilearnestly request the attention of members to the grand object of the Institution; that, namely, of enlarging our knowledge of the geological structure of Cornwall. It 1s impos- sible for a few members to undertake the investigation of the whole county. It is, therefore, hoped, that with a view of enabling the Society to complete its long-promised, but still very defective geological map, members wil], im their respective dis- tricts, endeavour to ascertain the nature and relations of the rocks, and transmit their observations made, and specimens collected, from time to time, to the Secretary, who will be very ready to assist their inquiries by any advice or information in his power. Any person, even although unacquainted with the prin- ciples of geological science, can, it is obvious, collect specimens of the various rocks in his vicinity ; and members are requested to bear this in mind, with the assurance that collections of this kind, with the various localities of the specimens affixed, will very materially promote the important»object in view. One grand desideratum, and which might be very easily supphed by members resident in the different parts of the county, is to ascer- tain the exact limits of the different Granite and Kallas districts. The farmers and miners in any part of Cornwall could give this information to any gentleman that would take the trouble to record it, or to trace the boundary lines in any of the cownty maps.” By order, Joun Fores, See, Sept. 21, 1819. 1820.] Royal Geological Society of Cornwall. 145° The following papers have been read since the last report : I. On the Throw of Veins. By Fred. Hall, Esq.—II. On the Importance of Mineralogical and Geological Knowledge to the practical Miner. By J. Forbes, M.D. Sec.—III. On the Granite ‘Veins of Cornwall. By J. Carne, Esq. F.R.S. Hon. M.G:S. Member of the Society. —1V. An Account of the Alluvial Depo- sitions at Sandrycock. By the late P. Rashleigh, Esq.— V. Observations on the Alluvial Strata of Poth, Sandrycock, and Pentuan. By J. Hawkins, Esq. F.R.S. M.G.S. Hon. Member of the Society.—VI. On the Precipitation of Copper. By J. Carne, Esq. F.R.S. &c.—VII. On the Geology of Saint Michael’s Mount. By Dr. Forbes.—VHI. On Elvan Courses. By D. Gilbert, Esq. Vice-President of the Royal Society, President. —IX. On the Intersection of Lodes in the Direction of their Dip or Underlie. By J. Hawkins, Esq. F.R.S. &.—X. On the Geology of the West of Cornwall, Part II. By Dr. Forbes.— XI. Appendix to the above.» By Prof. Jameson.—XII. Obser- vations and Experiments on the Construction and Use of a Safety Bar. By J. Ayrton Paris, M.D. F.L.S. Hon. Member of the Society.—XIII. On the different Processes employed in Blasting Rocks ; being an Appendix to Dr. Paris’s paper. By Dr. Forbes.—XIV. On the l'emperature of the Mines of Corn- wall. By R. W. Fox, Esq. Member of the Society —XV. On the Temperature of Mines. By Dr. Forbes.—XVI1. Notice on the Geology of the Neighbourhood of Sidmouth... By C. Wor- thingtor, Esq—XVII. On the Origin of the Cornish. By the Rey. S. Greatheed.— XVIII. Notice on the Cornish Minerals in the British Museum. By C. Konig, Esq. F.R.S. Hon. Member of the Society—XIX. On the Transmission of Heat through different Surfaces. By R. W. Fox, Esq.—XX. Notice on the Coal Field of Pontypool. By W. Llewellin, Esq—XXI. Onan Ebbing and Flowing Spring. By M. Tracelle.—XXII. Notice on the Employment of a Mixture of Sawdust and Gunpowder in Blasting Rocks. By Sir C. Hawkins, Bart. M.P. F.R.S. a Vice- President of the Society.—X XIII. Notice of the Quantity of Tin and Copper raised in Cornwall; and of the Quantity of Copper raised in Great Britain and Ireland in the Year ending June 30,1819. By Joseph Carne, Esq. F.R.S. &e. At the Anniversary Meeting, Sept. 21, 1819, D. Gilbert, Esq. M.P. V.P.R.S. Pres. in the Chair, the Report of the Council being read, it was resolved, That it be printed and circulated among the members. That the thanks of the Society be presented, 1. To the authors of the various papers read; and the donors of specimens, books, &c. 2. To the officers of the Society. That the seed of Dr. Paris and Dr. Forbes on the subject of blasting rocks be printed and circulated among the county mines, Vou. XV. N° II, K 146 Scientific Intelligence. [Frs. Comparative View of the Number of Members.—Last anniver- sary, 172.; removed and dead, 12; elected this year, 4; total, 164. Officers and Council for the present Year. President.—D. Gilbert, Esq. M.P. V.P.R.S. &c. &e. Vice-Presidents.—Sir Rose Price, Bart.; Sir W. Lemon, Bart.; L. C. Daubuz, Esq.; Rev. G. Treweeke. Secretary.—John Forbes, M.D. Treasurer.—Henry Boase, Esq. Librarian.—Rev. C. V. Le Grice, A.M. Curator.—Edward C. Giddy, Esq. Assistant-Secretary.—R. Moyle, Jun. Esq. The Council.—J. Carne, Esq.; T. Hartley, Esq.; M. P. Moyle, Esq. ; J. Rule, Esq. ; J. Tremenheere, Esq.; Rev. Uriah Tonkin; J. Giddy, Esq.; W. Sandys, Esq.; G. D. John, Esq.; J. Ste- vens, Esq. ArTICLE IX. SCIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS CONNECTED WITH SCIENCE, \. Anatysis of a Specimen of Blende. By Du Menil, Apothecary ‘ at Wunstorf. The colour of the mineral was reddish-brown. Its fracture was foliated. Its specific gravity was 4:061. Its powder was light-brown. The analysis conducted in the same manner as mine, deseribed in a preceding volume of the Annals of Philosophy, gave the following constituents : Sulphur: 2... 2.6... dE Co Lek ap Ramet leates 23°16 Ree oan = Co: | en a 68-48 Basins.) i801 eee BOGS ooea Seas 8-08 49-86 99-72 | ais che a a ne ae tee 0:14 0:28 50-00 100-00 (Schweigger’s Journal, xxiv. 67.) AI. Chemical Analysis of Egeran. By Stanislaus Count Duniz Borkowski. The mineral called Egeran by Werner, and considered by him . as a species distinct from idocrase, is found at Haslau, near Eger, in Bohemia, and has for some years been well known to mineralogists. Haiiy considers it as a variety of idocrase ; and ns far as can be judged from the cleavage, this opinion seems to 1820.] ‘Scientific Intelligence. 147 be so far correct that the primitive form of the crystals is the same in both. At the same time there is a considerable differ- ence in the appearance of the two minerals, and likewise in the chemical composition, though this last may be owing to foreign matter with which the Egeran is always contaminated. Its specific gravity is 3°294. The following table exhibits the constituents of Egeran, as determined by the analysis of Count Borkowski : OE ee eA Ra 4] POET >. oo aetna were ae 22 ENTE hia sidinie ho RO aL ee We ee 22 SMAGROORD Ls one ters cnaye aes 3 BLOT Niche site) ave’ cr aa oceans rears 6 DTANBANESE. Fk Del oso. ey lee 2 GERAD? Oe Oh eee eee ao ae 1 97 (Schweigger’s Journal, xxiii. 387.) Idocrase, according to the analysis of Klaproth, is composed as follows : eae ko SNe ates BM easels 85°50 SAW, & 6s cra. versie pe hse 22°25 ames. vc ate © ae Ae ae 33°00 Oxide’ of. ita 3500404 oe «3 7°50 Oxide of manganese. ...... 0°25 98°50 So that Egeran contains less silica and more lime than idocrase. But if a mineral from Siberia, which Klaproth considered as an idocrase, was really one, as there is every reason, from his description of it, to conclude, then the compcsition of idocrase and Egeran is more nearly the same. Klaproth found the com- position of the Siberian mineral as follows : cosy acerca Hapoks vb arunarinior syn 42-00 MIRIAM 2 (hicks Mcyareg en obipnlae 16°25 INIRSD < ch 34-00 Oxide of iron. ....... income eh. PE Oxide of manganese. ...... Trace 97°75 The specific gravity of the Siberian mineral was 3-365— 3°390. Its colour was dark olive-green. The crystals were rectangular four-sided prisms, with the edges sometimes so much truncated that they assumed the appearance of eight-sided prisms. ; III. New Nickel Ore. Cronstedt made known a new nickel ore found at Helsing, in K 2 148 Scientific Intelligence. . [Frs. Sweden ; but did not describe it. Prof. Pfaff, of Kiel, has lately published a description and analysis of it. Of these I shall give an abstract in this place. The colour of the mineral, when recently broken, is light lead- grey, approaching to tin-white ; but it gradually tarnishes, and approaches the appearance of copper nickel. It occurs massive. The lustre of the fracture is splendid and vitreous. The fracture is foliated. Composed of granular distinct concretions, resembling steel- grained galena. Fragments indeterminate and blunt-edged. Opaque ; streak similar. Semihard ; very easily frangible ; specific gravity, 6-129. Its constituents are as follows: Penis 17, be wet Sess AE Pe ee AYsenite Soot ee ee eee 45°90 Trot’ fe S.42 ee cree Moan aa. 02465 Sulphur . Bahay teiags io ous 12°36 93-14 (Schweigger’s Journal, xxii. 253.) IV. Position of Lyons. In the year 1811, Baron von Zach determined the latitude of this city by means of 262 observations to be 45° 45’ 57:37”. Gabriel Mouton, a celebrated astronomer of Lyons, during the 17th century, determined the latitude to be 45° 45’ 35:1”. But the position of his Observatory is not accurately known. The longitude is 10’ in time E. from Paris, or 22° 29’ 9” E. of Ferro- —(Correspondence Astronomique du Baron de Zach, 1. 205.) V. Clock. The first clock ever known in France was erected in the fifth century, in the Cathedral church of Lyons. Gondebaut, or Gombaut III. King of Burgundy, having been informed that Theoderic, King of the Goths, who resided at that time in Ravenna, had machines: which marked the order of time, according to the movements of the heaven and stars, wrote to him requesting to have one. Theoderic gave orders to the celebrated Boccius to make for him two such as perfect as pos- sible. Theoderic sent them to Gondebaut, with an excellent letter which may be seenin the works of Cassiodorus, Secretary of State to Theoderic, who was accustomed towards the end of his days, after he had retired from public affairs, to amuse him- self with making quadrants, clocks, and perpetual lamps.— (Ibid. p. 225.) > ad —1820.] Scientyjic Intelligence. 149 VI. Diéclination of the Needle at Lyons. iol, my November. 3. .-3...0.0 01. 15° 45° W Dae ee. ss Cae) tei a ook we 16 00 i7e5nmiDecember vais. Lo. :. 16 30 1757, in Degembers) inten sly, © ¢ Kerb BMRA LSE 4 sick Shope le ft tales 18 30 Pe ER Se AS 18 45 Thus the increase amounts to 9’ or 10’ in the year.—(Ibid. p.223.) VII. Position of Lucca. Father Inghirami, during a residence at Lucca in 1818, had an opportunity of making a set of observations to determine the latitude and longitude of this celebrated city. The following are the results : Date froin c, oro /alct waits 43° 50’ 49:5” POROUS, F is' lee sie as 28 10 25:9 E. of Ferro. Iz 1809, Baron von Zach determined the difference between the longitudes of Pisa and Lucca by means of a chronometer. The result gave him for the longitude of Lucca, 28° 10’ 25:8” a result which almost coincides with the observations of Inghi- rami. The latitude of Lucca, determined by Baron von Zach’s observations, is, 43° 50’ 50:54”. Numbers which likewise correspond well with the determina- tion of Inghirami.—(Ibid. p. 227.) VIII. Position of Montpellier. The latitude of Montpellier was ascertained in 1811, by Baron. von Zach, and found to be 3° 36’ 15°71” The longitude is 6’ 10” in time E. from Paris.—(tbid. p. 247.) IX. Determination of some Places onthe Coast of Sicily. By Mr. Charles Rumker. | Latitude. | Longitude. Fiumicino. ...........|41° 45’ 0029° 52’ 00” E. of Ferro ie of stica. x... 4.5.7 pore 401 OL 30...62 0 Isle of Maritimo. ...... Homme Lan. |29) 43) . 45 Isle of Favignana...... 3/ .6/ 00 (29:.55. .9 OT ee a OH, wlb noe jolla ILia2i (Ibid. p. 249.) 150 Scientific. Intelligence. [Fes. X. Occultations of Stars behind the Moon, observed at the Obser- vatory of the Royal Academy of Turin between 1812 and 1817, with an Achromatic Telescope, of Dolland, of 42 Inches Focus, and 44 Lines of Opening. By M. Plana, Astronomer Royal. I am induced to copy the following table on account of the great utility that it may be of to navigators, &c, in determining the longitude of places. The longitude of Turin being accurately known, and the observations of M. Plana being celebrated for their accuracy. Date. Star eclipsed. Mean solar time. Circumstances. 1812 Oct. 21) ¢ of Taurus. 10) 7’ 58:8” imm, 29) 62 of Taurus. 8 A2 AT-2 imm, 22| Aldebaran. 12 4 32°5 imm. 1813. March 6] » Balene. 9 26 50:0 imm. 8} Aldebaran, ; se as iT sete, nou se le 8 13 14°5 emer. April 17) Libre. he 56 49-2 imm. 12 16 66 emer. A little doubtful, Nov. 7| » Balene. 2 56° T-2, imm. Dec. 28) | Aquarii. 5 8 7 50° imn. 9 14 35°3 emer. Doubtful to about 3” 18i4 . Jan.‘ 1 # Balene. 9 5l 15°9 ‘imm, Nov. 25} » Balene. 4 57 503 imm. 1815. March19} & Gemini. ; Il 44 20°7 imm, 12 29 $8 imer, | Doubtfultol” or 2”, 1816. Feb. 19| 6 Scorpion. 15 20 40-4 imm. , 16 “22 8:3~ emer. Doubtful. Oct. 4} 30 Piscis. 10 15 24 imm. Nov. $2] » Leonis. 14 18 541 imm. Rather doubtful. ; 15 28 I8°T emer. 1817. Feb. 2) » Leonis. 10 30 27:1 imm. 8) x Libre. 16 16 5671 imm, , 17 28 289 emer. March2$; » Leonis. 7 22 499 imm, I ; 8 34 55:5 emer. | 1” of uncertainty. (Ibid. p..272.) XI. Position of Places on the Coast of ihe Adriatic Sea, deter- mined by Capt. Smyth. Longitude E, Latitude. ‘From Greenwich.| From Ferro. Isle of Fano (western Point) so Ja. wees 39° 50’ 207/19° 19’ 50”/36° 59” 36” Isle of Merlere ......'389 52 50,19 35 10 87 14 55 Capo Drasti. ........ 39 47 10/19 42 O07 21 4 Fort Alessandro at Vido39 38 5 |19 55 38 |37 385 23 “Capo Bianco...... ..(39 20 50/20 6 50 }37 45 36 1820.] Scientific Intelligence. 45 The position of the coasts of the Adriatic Sea not being yet well determined, Baron von Zach has added a few more facts to those above stated by Capt. Smyth. It will be worth while to mention some of the principal of these. 1. Lecce, a town between Otranto and Brindisi, the Aletium of the ancients, was visited by Rizzi-Zannoni in 1786, who, being provided with an excellent Ramsden’s quadrant of two feet radius, determined its position as follows : Latitude, 40° 41’ 4-2”. 2. Baron von Zach, being at Venice in 1807, determined the position of a great number of places in that city. It will be sufficient to give one of these here; namely, the steeple of St. Mark. . Latitude ..... sates MED? QS" 58> 1/" Longitude........ 30 0 37:2 E. from Ferro. 3. Being at Rimini in 1808, a city belonging to the states of the church, Baron von Zach determined the position of the following places : Latitude. Longe ie (rr 44° 4’ 3771309 12” 187 Rimini palais Garampij..i. cd < PAA . BS 2d6 80h. ADU NGS Tour de la Fontanella. ............ 43. 59 2130 18 37 Convent sur le mont Laro. ........ 43 54 43 130 24 920 4. In 1799 the Austrian government sent the astronomer M. Bogdanich into Hungary to determine the geographical position of the principal places. Among the rest he determined the position of the two following places on the coast of the Adriatic. « Latitude, Longitude. Fiumi (garden of the Cordeliers). . {45° 20/ 107132° 5’ nOY Carlopago (garden of the Comm.)..J44 31 35. 82 54 40 5. M. Quenot on his return from the unfortunate expedition to Egypt about the end of 1798, determined the position of the two following places : Latitude, Longitude, RAGUSA... os os AZ? BO! BO" vais. 35°. 51’. 40” Sane sera. o,: : chs bel A 6 a 33 51 00 6. The brother of Baron von Zach, at that time in the Aus- trian service, was employed between 1801 and 1805 in making a precy of the Duchy of Venice. He determined the position of the following places on the coast of the Adriatic : 152 Scientific Intelligence. [Fes. | Latitude. | Longitude. BRUTE Spi aPaica(. + « sis. wlelirla Ris Blidjasa ata ABO AD! bAY IO eaten Mocea dec Tiel: :). (diets bea ais's oo seta yO. Sly Gia ee Caorle (Porto di Falconera)........ 45 35 ,42 30 33 49 Capord Isttia, (leita) ian srisis\ ean oe a | A): LOO) ilagmsermee Cavolino (Porto di Reve-vecchia)...'45 28 51 30 13 27 Duino (Porto dei Bagni).......... 45 46 50 31 3 48 ALG. i Sera's. a ei 5 ae avttaue. @ Phat’ cheeasenelnele A5 20 .J2' B2aia,. 30 Grado (Porto Grado) W803. 220 45. 40 17 31 3 36 PARTIE soo ici ba itisleine JA Qegaene: Neen 45 29 28 29 40 54 Mand ovcortello., os:c\ssle pei. ae meg 45 40 9 30 44 32 S. Georgio di Pirano (Istria). ...... 45 29 44 31. 14 19 DMRS UC. sconketeiedaie a < tk Cera anes 45 38 30.31) 26 53 7. Boscovick and Maire, while employed in laying down a map of the states of the church, determined the position of the following places : Latitude, ; Longitude. VANITG OND’ soe ears ats 's o's gia tele AO? STA fs hes B10 ORS” Wer iae eee A sajcusteeres 44 “hotelier 2 26 ah yee COMA GCHLO NH svi kis io oho leteietens AAS Ay eg Te ab et ty, oR 29 50 40 BG Ge APRS ed, «isla dene ee SF PaiLe OE sine okie 30; 40.928 Wermioes..; sah tveuus «cl cue 43 Oe ae Catia. alee Sliwne2Q2agiS WRGTELOM dscaveroietavwvctaistorcuewele A438 O72 OC ky Peet ea oh epoiae res PAGS ATOSE Fs eh arcuaiets stone) stele AS. Gb ales one 30 34 14 RAVENNA tee iete, «haan clerete AL MDD. OM ig tech QOF Fo e29 RRM... 6 xe. 2 Ue p ceroiaenneey 1A ee eee, 30°. 13 ».29 Ripa trams0ne.... < sijaso.0 0. A Set OS oA Naerey, fesse Plies 2 po3 SHIGA CUA Mois fai0 sie 'eiee sin aes AB: Abbe) EOE isha ee tous 30 52 23 (Ibid. p. 274.) XI. Isle of Elba. It has been commonly believed that the Isle of Elba, in con- sequence of the inexhaustible mines of iron in which it abounds, especially Mount Calamita, which is supposed to be a solid mass. of loadstone, has a sensible effect upon the needle. Hence it has been thought that vessels in the neighbourhood of this island could no longer depend upon the declination of their needies, being the same as at a distance. This was tried by Mr. Charles Rumker in 1818, but at the distance of two, three, or four nautical miles from the island he did not find that the needle in his vessel was in the least affected by the action of the island. The variation of the compass was 18° 18’ 40” W.— (Ibid.) XIII. Population of the Calton in Nov. 1819. The Calton is a suburb of Glasgow inhabited chiefly by jour- neymen manufacturers. It has been lately erected into a burgh of barony, and in consequence, the following enumeration of the - 1820.) Scientific Intelligence. 153 inhabitants and of their professions was taken. Itis adocument of so curious a nature that I think it well worth preserving, by inserting it into a journal more likely to be preserved than a e€ommon newspaper. Female householders. .......eeee0e. 1958 Labourers ‘and porters’... ee. ees 1097 IW GAREISA ose sce eos eae eae hake Coreen Lge > Wrights and sawyers. .....:........ 601 SSINGEMIAICETS ic «cece ¢ e/steiaeteigve waseretoter mals 721 AMOS ae ae caves siveisewseserse uses 253 COON SpINNETS . se. eae a ds eletelete os 839 Manufacturers... . 00.210.) 'a'. oe > a 120 Merchants (shopkeepers). .......... 101 Warpers and starchers...........+4- 283 Nailers and toolmakers..........000. 125 Blacksmiths and tinsmiths........... 233 MROORSEM OTS: Maes re ieiaalenstace’e ere ete lareuie iY) Der a0e: Waters iiaele oes sia < sinistovs ds 96 Witrenolsemen: ose. c/s crc oe aleve erties 153 Bricklayers and plasterers. ..... spies she Martone and slaters.". .. .. s,s. eee ee 229 EEL WINELSS kahs| oo, < emabMol dees ies s crore. c-alelnls 68 Preachers and teachers. .........%.0. 64 (RerES ‘ANC. SURVEYORS (22% 6... stake o's 119 Barbers and hecklers. ........2%.%.. 52 €ngravers and founders. .........+.. 100 PTINGETSHAMIC GURMELS 20... ais elalesdiererctere a 76 AU RUR WAIT R Soha ose coterie wr eis tele 0 38 SUSU SS OO es PSS SC 46 BAEC CAN TOTS yeva's- use a /at' «/ well ta raicelarers 18 Messengers and sheriff officers. ...... 15 LEIS RIVEVEST SS RS St AEE ae eaten A Ato 105 Watchmakers and china dealers...... 23 Brush and umbrella makers. ........ 33 Saddlers and tanners. ......s.ecese. 20 Srokers and ‘pedlars ...0....2.+.+.06 70 Coopers and gardeners. .........:.. 49 Pensioners and sailors........<0.c.. 101 Watchmen and chapmen............ 7] AU OVRICGEOES 2). < sw nltyeveuwd ae 6 6 sic 8)5cit hele 45 Glass and pin makers, engineers. .... 51 Brewers and bakers. ¢i<.cc. css scs ce 217 Carters and horse dealers. ....ssece. 209 Portioners and surgeons... ....2.+0+8 28 Lodgers and servants. ..........000. 1309 Grocers and spirit dealers. .....+.... 512 154 Screntific Intelligence. Nations. EGOLGH «fs en.ovinse> oan ane 060 eee Tish. "siicieiaie w cievete'.« Since eee cee PSS oie 00! aie 2 + om ateiatnatee Wikig PRBETLGANNS 10:5 ins, 6 5 Cigipuatche tie bt apo | MEME Sipe tes 1s le exes a/egeeetoLa sun oad SONGS Sioiaie vi actin sveierneeh an Kae the JE CN ae Sa OREIEN (5 oe iS 3,212 162 8 3 3 6 15,616 XIV. Meteorological Observations at Cork. By T. Holt, Esq. (With a Plate. See CL.) (To Dr, Thomson.) DEAR SIR, Cork, Oct. 9, 1819. I ENCLOSE you the report of my meteorological observations made in and near Cork, for the third quarter of 1819; and am, dear Sir, with due respect, Your obedient humble servant, Tuomas Hott. —<— REMARKS, JULY, 1. Cloudy; dry. 2. Rainy morn and.evening. 3. Cloudy. 4,5, 6. Bright days. 7. Bright; breeze. 8. Dry; clouded. 9, 10, 11, 12. Bright days, 13. Dry; overcast. 14, Rainy morning; cloudy. 15. Cloudy; showers. 16. Dry, dull day. 17. Bright. 18. Rainy ; cloudy. 19. Rainy; showery day. 20, 21, 22, 23,24. Bright days. 25. Cloudy; showers. 26. Dry; cloudy. 27, 28, 29, 30, 31. Bright days: AUGUST. 1, Bright ; thunder, 2. Ditto; lightning and thunder, with rain. 3. Overcast; dry. 4. Bright. 5, 6. Cloudy; light showers, 7. Cloudy; dry. * 8. Heavy showers. 9. Cloudy; dry. 10. Ditto; rainy evening. 11, Cloudy; dry. 12, Rainy.: 13. Overcast; dry. 14, Ditto, ditto. 15. Bright. 16, 17, 18. Bright days; fog morning and evening. 19,20, 21, 22, 23, 24. Bright days. 25, 26. Clouded, dry days. 27. Bright. 28,29. Heavy showers, 30. Ditto, ditto, windy. 31. Dry; windy. SEPTEMBER. Bright. Cioudy ; rainy evening. . Bright. . Rainy morning and evening. . Bright ; occasional showers. . Cloudy. Bright, Cloudy ; light showers. Rainy morn; light showers. 10, 11,12, 13, 14, 15, 16. Bright days, Cloudy. 1s. Bright. 19, Overcast. 20, 21, 22, 23. Bright days. 24,25, Light showers. 26, 27. Fair; rainy evenings, 28. Bright; occasional showers. 29. Bright; windy. 30, Rainy; windy. CHADS WM — Cell a Vy “ey arruryny hay y “peprsy inuppeg ay — sponge suowrmuyy 3 4a poavsbug hee li ee nocnng0 | PEE ere | Lagu nae 4S enbays i es ne cajouroaegy | TI 7d 4] x weer t aed 2 Aoremeany kop y mopesy wins jo 49 poouy | 1] _ [feds euler ode POCCODAbEcoon E e oP CPCODnConoEL lejoder|ena aleelelelols|ejojete B 7 +t He + 8 | Ht HH { a poane a t is | 7 _| XN }4 } (x ial T a Co | : 7 {ese {EEE EEE rr : a Cert 5 Pum ory eI + {| oF ices | | t a ' ale E a 7 F ‘SE = ‘ : | ) rn t vias pong, | : x E g JM ! at x : t t 1 | abun pryery, T T Tt iwi | + ie Per L | | 7 3 - ‘on t Tt C t we | : t 1 He +H NE a aeons htt +t ti out C] REE Ht | : t | ov sane + tt ‘ t t tt pe | H ‘ ++ a + Ca tity +44 44 Ht HH + 4 | +t cl oaee Pree +t Serer is b+ amt thy 4 ft +4 pte tt +4 ++ ++— Th Pee tt r t ae 3 | er on om On tT FEE EEE HEE O00 GEGOOuE do 9ULOULLOY,], it = - ki bt fe] ded SEC RCHOREECRORE | | | c PECeOSDEOEG ee meq le iz 4) Tel LPL Te ale LT ae +t {- ve 4 a GE Coo ASE nage 4 a Bi Fa L if PND? O98 a] a y t 6F a 4 we yo pany a a CI CI] | - a r f{ A |[ or | OF | || | — | by fas| ede cforlorarertert aladete|sfotefetatate Laguedgd as gsu bag rer Aga | d 4 : LS p : : = f , LOR. Pa =, i So Se =e mE os LoOULO.Te ET LI PE e 1820.] Scientific Intelligence. 155 RAIN. 1819. Inches, 1819, Inches. |} 1819. | Inches. July 2 0-390 Aug, 2 0-398 || Sept. 2, 0-312 8 0:294 5 0-058 4! 07521 11}. 0°035 6 0:140 5, 0-228 12 0-016 8 0:180 gi. ols i 0°636 j 0°156 | 9 07384 15 0-125 12 0-096 24, 0-180 18 0°785 28 0:364 25! 0:045 19 0:050 29 0-066 26, 0-054 25 0-160 30 0:958 27) 0-174 _—_———____—_— 31 0-145 | 98, 0-120 2-491 ee ELS 30! "245 2°571 leo : 2:395 2-571 2-491 TA5T XV. New Rockets: Capt. Schumacher, brother of Professor Schumacher, Astro- nomer Royal at Copenhagen, has invented a new kind of rocket, which is said greatly to surpass the Congreve rockets, both in their force and in the accuracy with which they may be thrown. The King of Denmark has established a new corps of artillery ( Baketer-corps) commanded by Capt. Schumacher, whose busi- ness is to throw these rockets. They ascend to a very great height in the air; and when they have reached the highest point, a globe of fire makes its appearance, which is so vivid that it may be seen at the distance of 70 miles. Capt. Schumacher elevated them in the island of Hjelm in 1816, and they were seen distinctly by his brother at Copenhagen at the distance of 171 German miles.—(Correspondence Astronomique du Baron de Zach, 1. p. 266.) XVI. Pink Sediment of Urine. By Dr. Prout. I lately had an opportunity of examining the most marked specimen of pink sediment I had everseen. It consisted almost entirely of the lithate of ammonia. Pink sediments in general consist either of this substance, or of the lithate of soda mixed with more or less of the phosphates. When the lithate of soda and the phosphates prevail, the sediment usually assumes the form of what has heen denominated the lateritious sediment. In specimens of this latter description, I have several times found nitric acid ; and in all cases I have satisfied myself that the red colour of these sediments depends upon some slight mixture of the purpurate of ammonia, or of soda, according as the sediment itself consists of the lithate of ammonia or soda. Perhaps the formation of the purpuric acid may be explained by supposing that the nitric and lithic acids are secreted together, and that the purpuric acid, or rather the purpurate of ammonia, is formed by the action of the nitric upon the lithic acid, Col. Beaufoy’s Magnetical > ARTICLE X. [Fes. Magznetical and Meteorological Observations. By Col. Beaufoy, F.R.S. Bushey Heath, near Stanmore. Latitude 51° 37/42” North. Longitude West in time 1’ 20-7 Magnetical Observations, 1819. — Variation West. 156 Month. Hour. Dec. 1} 8h 35’ Divas ao SiS teau PA a ee 5] 48. 45 6} 8 35 7| 8 40, 8]| 8 40 9| § 45 10; 8 40 11 8 45 12} 8 40 13} 8 45 14} 8 45 15| 8) 45 16; 8 40 17; — — 18} 8 40 19} 8 45 20} 8 50 Lie v8 45, 22} 8 40 23| § 45 24); 8 40 25} 8 Ad 26} 8 40 Btw 8. AS || 28) 8 45 29} 8 45 30). 8 45 31} 8 45 Mean for Month. \s a Morning Observ. Variation. PAPE Se: 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 24 32 32 34 32 32 33 35 33 52" 10 40 Noon Observ. Hour. fay pone ay =o en ee Variation. 240 39/- 19” 24 38 48 24°36 55 24 37 AT 24 37 23 Evening Observ. Hour. Owing to the shortness of the days, evening observations discontinued. Variation. eee Rain, by the pluviameter, between noon the Ist of Decem- ber, and noon the Ist of January, 2-429 inches. Evaporation during the same period, 0°71 inch. 4 1820.] and Meteorological Observations. 157 Meteorological Observations. 7 Time, Barom,| Ther. | Hyg. | Wind. |{Velocity.|Weatier.] Six’s, Month. Dec. Inches, Feet. Morn.,..| 29-277 459 87° wWwnNw Showery| 45° J Noon... .| 29-456 Aq 13 WNW Very fine| 48 Even | o— —_ —_ — oe 952 Morn....| 29°513 | 45 | 85 SSW Rain : ee: 2 2|Noon....| 29-453 | 47 | 89 sw Rain, fog] 48 Even ....J o— _- — — — ‘ 99 Morn....| 29-696 33 86 Sby W Clear by 3< {Noon....} 29°690 39 73 SSW Very fine} 42 Even..,.) — _ _ — —_ ‘ 361 Morn....| 29-225 _ 92 SSW Hardrain 2 ot Noon,...} 29°105 | 47 Tl | W by N Cloudy AT Even... —_ — cad = — ; 38 Morn....| 29-400 33 83 NE Rain 2) Noon....| 297443 38 89 ENE Cloudy 39 Even ....| — — = — => 34 (|Morn....| 29-560 35 718 ENE Cloudy ‘ ‘i Noon....| 29-578 | 34 80 ENE Sleet 35 Even.. _— — = = ie 92 Morn....| 29°558 32 83 NE Snow ‘ if 4 Noon....| 29°516 |. 32 83 NE Sleet 322. Even,...) — as = = — 272 Morn....| 29°516 | 28 76 B Cloudy ‘ = 5} Noon....| 29°545 27 68 E Very fine] 27 Even....|° — — == => _ 19 Morn,...| 29-562 20 8] NE Very fine ‘ 99 |Noon....| 29°550 27 76 ENE Cloudy 27 Even... _ — — —_ — os Morn....| 29°400 26 83 NNE Snow ‘ 104 |Noon,...| 29°424 | 29 78 NNW Snow 29 Even....) — — — = — }2 1s Morn,...| 29°517 20 18 W by N . Clear 5 114 |Noon....| 29:510 | 26 65 W by S Clear QT Even: ....6.|°°— = — as Ae of Morn....| 29-451 27 81 Wsw Fine # 12} Noon....| 29-405 | 33 | 10 WwW Cloudy | 333 Even... — = — ay a a Morn....| 29:00 | 25 | 72 | WNW Clear ; se 13 |Noon....| 29-283 | 30°] 70 | WNW Cloudy | 33 Bye 5. i.) — _ _ — — Morn....| 29-240 | 23 | 83 | SW bys Fine ‘ 22 149 INoon....| 29153 | 98 | 78 | SW by S Very fine| 332 Even....) | — — — — — : > Morn....| 28°955 30 83 WSW Cloudy rs 154 |Noon....| 28-956 | 35 | 73 WSw Cloudy | 36 liven... — — a _— —_ 29 Morn,...| 29°355 | 32 79 Ww Very fine ‘ re 16 oon... 29-454 | 36 | 71 | WbyN Very fine] 372 ven...) — — — = us {|Mom.... 29-193 | — | 93 SSE Stormy bi 179 |Noon....| 28-985 | 40 | 91 s Rain 50% RieVeN <-25(2 °° — — —_— — — 2 Morn....| 28-903 | 50 | 92 Sw Fog, rain ‘ 853 184 |Noon....} 28-986 52 85 WSW Cloudy 52 EVEN); « 6i6|)-4 — _ _ _- — 49 Morn....| 29376 | 50 | 94 sw Fog ‘ 19) |Noon....| 29-350 51 93 SW Rain 53 Even....| — — — — ‘= / , ‘ 158 Col. Beaufoy’s Meteorological Observations. (Fen. Month. | Time. | Barom. | Ther.| Hyg. Wind. /|Velocity.| Weather.|Six’s. Dec. Inches, Feet. Morn,,..| 29°190 51° 95° SW Rain 50 at Noon,...) 29°183 54 | 83 Ww Showery | -54 Even..... — = _ _— — Morn....| 29-484 | 44 | 80 | NNW Cloudy ‘ 44 a Noop....| 29°418 _ 83 SE Rain 54 Even....| — — — _ — Morn....| 29216 | 50 | 99 | WbyS Rain ‘ al 22} Noon....| 29°243 | 51 73. W by N Cloudy 524 Even....| — — — _ _- Morn....| 28°828 | 41 | 82 INW by W Cloudy ba 23< |Noon....| 28°838 Al 69 INW by W Fine 44 Even «../ 5 — — a — — j Morn....| 28:893 | 3 st | Ws Very fine ; 30 24< |Noon....| 28°860 35 72 Var. Very fine} 362 Even....) — a == _ at z Morn....| 28865 | 31 | 80 |NWbyN Cloudy at 252 |Noon...., 28-905 | 32 | 73 |NWbyN Veryfine| 322 Even....) — = ae a — My Morn....| 29-000 | 24 | se Ww Very fine|§ 73 20) Noon....| 29008 |. 30 | 75 s Clear 30 Even....) — Sor i = _ Morn,...| 28-770 | 28 | 79 | RSE Fine ' 265 27< |Noon....| 28°964 31 13 ESE Fine BW Even....| — ae —< — = ts Morn....| 28°996 | 31 | 78 NE Cloudy |$ 2° 234 Noon....| 28°992 31 TA ENE Snow 31k Even..... — — == — — Morn...) 29°130 | 26 | 84 N Cloudy ; 2 29% |Noon....| 297158 | 30 17 NNW Cloudy 30 Even ....|. — = — bag _ Morn....| 297039 | 21 | 80 | WSW Fine 193 305 |Noon....| 28°974 | 29 15 Ss ‘Cloudy 294 BVEM: cro. =), —— = =m oe —— Morn....| 28-868 | 25 | 717 | SSE Very fine ‘ ‘as 31¢ |Noon....| 28°863 31 67 SSW Very fine} 31 Brew:,2.) =.) | is — —- ANNUAL RAIN TABLE. Month, Rain, Evaporation. January, ........ 1906 1-400 February ........ 2°823 1-430 Maret. cicas. ee oc 1-153 * 2°680 MST. ics Siac 2468 3'440 1 ae 3-063 4°530 TUNE 46 Sars ieee 1-950 4°250 July..... se ceeiosls 1-514 : 4-930 AUBUSt 2. ..00 0 2:520 4-720 September....... 3°213 3°550 October. ..... wiatt 1-610 2.280 November. ...... 1-761 1-230 December. ....,. 2°429 0-710 Mean...... 26-415 | —- $5+150 As the evaporation for the year exceeds the quantity of rain, it may be advisa-~ ble to describe the evaporating apparatus. It consists of a hollow cylinder, one foot in diameter, elevated to the same height as the rain-guage, and sheltered by a copper roof, placed-some inches above the edge of the bason. The eves of the roof project, which permitsa free current of air, but excludes the rain, 1820.] Mr. Howard’s Meteorological Table. 159 ArticLe XI. METEOROLOGICAL TABLE. BaromeEtTer,| THERMOMETER, ‘Hygr, at Wind. | Max.| Min. | Max. Min, | Evap. |Rain.| 9 a.m. W/30:08 29°81] 49 31 99 |O W/|30°23 30 02} 50 25 _— 88 W/|30°23 29°81] 44 25, = 100 W|29:96.29'70} 48 -| 38 60} 100 E/30°10,29-96| 41 34 79 E}30°15 30°10) 37 33 — 81 E/30°15,30°14| 33 28 89 E _{30°1930°15| 30 18 73 QIN _E30°1530-04, 30 23 — 6s | p N_ {30°15 30°04) 33 10 87 W/|30'1430'11) 31 13 84 W/30 11:29°95| 38 13 = 75 13)S _W)29°95,29°88) 36 20 a 88 14S W)29'8829°61| 37 23 We” 92 15| W_ |29-97\29'58} 38 24 so 16)N W/30'10,29 81 Al 27 41; 85 17|S _ E/29°81;29'41) 53 38 44, 98 |@ 18'S W 29:89 29:41) 55 50 a 100 19'S W/29'8929:76| 54 52 15} 99 20/8 W/\30-:00.29'74| 56 44 100 21} Var. |30°00.29°79| 52 | 41 56 | 49 84 2S W 29°79,29'30) 54 48 Bis 95 23;|N W)29°39.29°30) 49 2 o1 1 ¢ 248 W 29°39)29'35) 36 24 96 25|N W)29'58 29°39) 34 21 85 26|S W/29°58)29'55| 32 23 81 27/8 E29°59 20°55| 34 Q 85 28IN —_E'29-73/29'59| 35 23 | — 80 29} N_ |29°73'29°66| 32 19 06 30/S W/\29:66,29°51| 32 17 92 3IISESW)29°51,29'40| 33 1 23'| 05| 86 | $0:23\29'30/ 56 | 10 | 0-79 |2:45'68—100 i The observations in each line of the table apply to a period of twenty-four hours, beginning at 9 A, M. on the day indicated in the first column, A dash denotes, that the result is included in the next following observation. 160 Mr. Howard’s Meteorological Journal. [Fre. 1820. REMARKS. Twelfth Month.—\. Cloudy. 2. Rainy morning. 3. Hoar frost: fine day. 4, Rainy morning and evening. 5, 6, Overcast. 7, Some snow this morning = much wind at night. 8. Fine: windy: thermometer at Tottenham, 16°. 9. Snow in the night, covering the ground above an inch deep, 10. Cirrus, Cirrocumulus = fine: thermometer at Tottenham, 8°. 11. Very foggy morning: gloomy day. 12. Morning, fine: snow and sleet, p.m. 13, A little sleet: about six, p.m. a shower of rain, after which it began to frecze again. 14. Cirrocumulus: fine. 15. Foggy morning: athaw commencedabout 10, a,m.and went on till about thesame hour, p.m. i6. Foggy: frost continued through the day, but at night it was very stormy, with rain from the Sand SE. 17. Rainy. 18—20. Cloudy and gloomy. 91. Raia. 23. Cirrus, Cirrostratus, Cumulostratus, 24—27. Hoar frosts: fair. 28, A pretty considerable fall of snow, leaving an inch depth on the ground after, in part, melting as itfell, 29—31, Fine: Cirrus: snow on the ground. RESULTS, Winds: N,2; NE,5; E,1; SE,3; SW,14; W,1; NW, 4; Var. 1. Barometer: Mean height Por the months. stot! « «eeccice wolgeels acieiaey Ca cles te. eee ean For the lunar period, ending the 8th, ............. 29°875 For 14 days, ending the 10th (moon north) ...... 29-989 For 13 days, ending the 23d (moon south) ....,... 29°790 Thermometer: Mean height Bor the:month vj. 1+ ~ scons ote Be viclafeletelaisio(etas ath ei - 34-129 For the lunar period (as above) .......+--se00 «2. 3188 For 30 days, the sun in Sagittarius............6... 36°63 Hygrometer: Mean for the month . wv dais care dala alee date Baie EV GpOraHOn ss .\ccsics's a o0'<'siaciein vies cles eiciee cle ve sade miacisiveminicesiga, (Onto mes FRAUD Faso eiafojoia'e ia fo, 0\ als vo(o ju oic.nisiviciare einievaisieieiaiciet he's afaera dias CORUED oskes ora Byfa SCCONG CUAL Eas a aps a's\duiela'v oss sive Slcaieiacn'd« cpalelecamemeistanisiere.) eee AMM aL LOELENURIN, 65,6 care wie’ n’erdvinie'oris/sjanieialciels s)a vain ante eltereicise ates) Ger piee —< *, * The mean temperature of the month at Tottenham, with three days’ observa- tions, in different parts supplied from the above table, is 33-569. The thermometer at Tottenham has rather the more open exposure of the two. A fine exhibition of the Aurora Borealis was observed there between 11 and 12, p,m, on the 14th of the present month. Laboratory, Stratford, First Month, 25, 1820, L, HOWARD. ANNALS OF PHILOSOPHY. ee ee SS MARCH, 1820. ArrTIcLeE I, Biographical Account of Stephen Hales, D.D. F.R.S. &c. Rector of Farringdon, Hampshire, and Minister of Teddington, Middlesex. DR. HALES was born in the county of Kent on Sept.7, 1677. He was the son of Thomas Hales and Mary Wood. His family was one of the oldest and most respectable in the whole county, and his grandfather had been raised to the dignity of a baronet. He acquired the rudiments of his education in his father’s house. His tutors seem to have confined their instructions to those branches of knowledge which were considered as connected with the ecclesiastical profession to which he was destined. Nothing at this early age announced the great talents which he had received from nature, unless we consider the assiduity with which he devoted himself to his studies, and the.correctness of his mode of thinking, as indications of genius. And in fact they often constitute the dawn of a great man’s career, making their Serine before any other indication of great abilities can be observed. He went to Cambridge at the age of 19, and became a pen- sioner in Bennet College. Here he took his — and here he began to show a fondness for mathematics and physics. He devoted himself to these pursuits with such ardour that without any other assistance than his own labour, he made himself suffi- ag acquainted with the system of Copernicus to represent it m a kind of planisphere, in which the planets were placed in their natural order, and made their revolutions in times propor- tional to the times of their real revolutions. Sach a machine Vou. XV. N° III. L 162 Biographical Account of [Manrcn, was at that time but little known, though they have since become very common in England under the name of Orreries ; because the Earl of Orrery employed Mr. Graham to construct one of the first of these machines, which served afterwards as a model for all subsequent ones. A machine of this kind constructed by Mr. Roemer was exhibited to the French Academy in the year 1680.* But Dr. Hales was not aware of any such previous invention when he constructed his own machine. Dr. Stukely, who afterwards settled in London as a physician, was at that. time in Cambridge, and in the same college with Dr. Hales. These two young gentlemen had a similarity of taste which soon rendered them inseparable companions. They traversed the environs of Cambridge in search of plants, with Mr. Ray’s Description of the Plants which grow in the neigh- bourhood of Cambridge, for their guide. This faithful guide often led them into places. very little frequented, where they could obtain nothing to satisfy their thirst but sour small beer. This beer Dr. Hales rendered drinkable on the spot by infusing into it a quantity of wormwood or some other bitter plant, to the’ great astonishment of his hosts. Thus the knowledge cf plants began already to reward him for the trouble which it cost him to acquire it. To the study of botany was joined that of chemistry ; and our two friends, not satisfied with the ordinary lectures of the pro- fessor, repeated in their own apartments various experiments of Boyle, and attended with the greatest assiduity the chemical processes carried on at Trinity College in a laboratory that had belonged to Sir Isaac Newton, and in which the chemical manuscripts of this great man had been burned by a fatal acci- dent. Such was the ardour with which Hales devoted himself to this study, that he seems already to have conceived that he should on a future day have it in his power to repair this great loss to the chemical world. Anatomy, which is so essential a part of science, was not neglected by our two young gentlemen. Hales made such progress in it that he even contrived a new mode of rendering the vesicles of the lungs visible to the eye. He fixed a gun- barrel to the windpipe still attached to the lungs. This barrel was heated by passing it through a chatter, and he blew through it; for several hours, into the lungs, a hot dry air, which dried all the membranes and vesicles, keeping them still in a state of distention. He then poured in a quantity of melted tin ; for this metal melts at a temperature so low that when in fusion it does not destroy the texture of animal bodies. When every thing was cold, he destroyed the whole of the lungs by a long maceration. there remained a fine anatomic tree, which not only represented exactly the figure of the interior of the lungs, but enabled him * See Hist. de Acad. tom, i, p. 317, 1820.] the Rev. Dr. Hales. 163 to form some notion of its total capacity, and of its different cavities. This ingenious idea, which would have done honour to Ruysch or to Winslow, was the fruit of the reflections of a student of anatomy. How great expectations might have been formed of the discoveries of his mature years. When we consider the astonishing progress which Hales made in every branch of physics, we should be tempted to conclude that he devoted the whole of his time to these pursuits. But this would be a great mistake. His physical studies did not in the least interfere with those which had been the chief motive for his repairing to Cambridge ; and he had made such progress in his theological studies that those persons who had the direc- tion of the College being afraid that so promising an associate should escape them, got him made a fellow before the age of 25 years, and though at the time there was no vacant fellowship. He took successively all his degrees, and soon after was named Dean of Ely ; so firmly was his ecclesiastical reputation esta- blished. It is a difficult task for most persons to acquire a com- petent knowledge of a single science; but Dr. Hales had abilities sufficient to render himself almost equally well skilled in them all. As soon as he had taken orders, he was,appointed curate of Teddington, in the county of Middlesex ; afterwards he got the living of Oxlock, in the county of Somerset, which he exchanged for the living of Farringdon, in Hampshire, and in all these situations he performed his clerical duties with the utmost pro- ptiety, and to the entire satisfaction of his parishioners. He was elected a fellow of the Royal Society in the year 1718, and the year following: he. began to read to that learned body some experiments upon the effect of the heat of the sun im elevating thesap in trees. The Society, struck with the importance of his investigations, exhorted him. to continue them. He complied with their request ; and in the year 1727 published the fruits of his researches under the title of “ Statical Essays ; containing vegetable Statics ; or an Account of some statical Experiments on the Sap in Vegetables, being an Essay towards a natural History of Vegetation; of Use to those who are curious in the Culture and Improvement of Gardening, Kc. -Also a Specimen of an Attempt to analyze the Air by a great Variety of Chymio- Statical Experiments, which were read at several Meetings before the Royal Society.’ This work, which immediately raised the author to the very first rank among British philosopliers, was dedicated to George Il. at that time Prince of Wales. Few books were ever more favourably received by the public, and few ever deserved a better reception. Most of the experi- ments were quite new, and the hand of genius was every where conspicuous in them, which is alone capable of opening a new road to great discoveries. He made no attempt to rear any L2 164 Biographical Account of (Mancn ; hypothesis of his own; but stated experiments which completely overturned all the hypotheses previously contrived to account for the motion of the sap in trees. They often led him to surprising conclusions. Could it have been believed, for example, that the force with which a vine branch draws the sap, at the time when the sap flows, is equal to the pressure of a column of water 36 feet in height. Yet Dr. Hales demonstrated this by cementing glass tubes to the extremities of vine branches cut at that season, and observing how high the sap issuing out from the branch rose. Similar experiments, but made in a different season of the year, and upon a great number of plants, informed him of the force and the quantity of transpiration of plants, which he contrived to collect and render sensible. The motion of the sap in trees, and even the existence of vessels of communication which allow it to pass laterally from one side to the other, are rendered obvious to the eyes with an inconceivable ingenuity. He estimates the effect of the heat of the sun upon different parts of trees, and that of the temperature of the earth, which he deter- mines to as great a depth as the roots usually reach. He explains the use of the leaves, till that time very little under- stood, and which, according to him, are the organs by which plants exhale during the day the liquid which they draw from the earth; and which, during the night, on the contrary, draw back again the moisture which they find in the air. This alter- nate motion in plants is a substitute for the circulation of the blood in animals. It would occupy too much room to specify all the curious experiments related in the first part of this work, and the singular consequences which he deduces from them. But it would be improper to overlook the modest reserve with which he every where restricts himself to a bare statement of facts without hazarding any other conclusions than those which a rigid calculation have converted into certainties. It is unfor- tunate for the progress of physics that this sage conduct has been too seldom imitated. The second part of this work is, if possible, still more interest- ing than the first. It constitutes the real foundation of pneu- matic chemistry; for it is doubtful whether Dr. Black, who produced the first great impulse, would have been able to have made out the constitution of limestone had it not been for the previous experiments of Hales. Dr. Black himself informs us that it was the previous experiments of Dr. Hales on limestone, who demonstrated that when this mineral is dissolved in acids, a quantity of air is disengaged from it, that led him first to draw the conclusion, that limestone is a compound of quicklime and air. An examination of the air, which he called fixed air, led him to the knowledge of its nature ; and the properties of fixed air were afterwards fully investigated by Mr. Cavendish and 6 1820.] « the Rev. Dr. Hales. 165 Dr. Priestley. This produced the taste for pneumatic chemistry, and of course was the occasion of all the subsequent discoveries in this most fertile region of the science. Many interesting experiments had been made on air for a whole century before Hales began his career. But hitherto it had been examined only as a heavy, transparent, and elastic body. No one had thought that air was capable of existing in a great variety of substances, deprived of its elastic state, but capable, when favourable circumstances occurred, of abe | all the elasticity of air. Hales demonstrated that almost a vegetable, animal, and mineral substances, contain air, and that the quantity in many cases is astonishingly great. Thus froma piece of oak wood he extracted a quantity of air equivalent to 200 times its bulk, and constituting about a third part of the weight. It is true that Dr. Hales did not suspect that the elastic fluids thus obtained from vegetable, animal, and even mineral bodies, differed entirely in their nature from common air, and consisted of elastic bodies of a very different nature. But it was a great step to call the attention of chemists to the extrication of airs from different bodies. It was natural, after being aware of the fact, that elastic fluids are extricated from a great variety of bodies for chemists to turn their attention to the properties of the elasti¢ fluids themselves. This accordingly was done. by Cavendish, Priestley, and Scheele. These bodies were characterized by names according to their characters. The next step was to determine the constituents of these elastic fluids. This was the occupation of Lavoisier and his followers. And of late years, chiefly in consequence of the atomic theory and the theory of volumes, for which we are indebted respect- ively to Dalton and Gay-Lussac, this important department of chemistry is in a great measure completed. Thus a new and most important chemical rout which was first opened by Dr Hales has only been completely explored in our own day and within these few years. Hales’s experiments on respiration, on the quantity of air deprived of its elasticity by combustion, and by various kinds of vapours, deserve a careful perusal. If he did not see or even suspect the whole truth, he at least greatly facilitated the future investigations of chemists after the composition of atmospherical air, the true nature of combustion, and the important part which oxygen performs in it, were known. This work of Dr. Hales was translated into French by Buffon; and the translation speedily raised the reputation of the author as high on the con- tinent as the original work had already done in Great Britain. The success of his experiments on the motion of the sap in plants naturally led him to examine the motion of the blood in animals, previqualy much better known than the former. Accord- mgly in 1733 he published, by order of the Royal Society, a 166 Biographical Account of [Marcu, collection of his experiments and conclusions under the title of “ Hemastatics, or Statics of the Blood.” He exhibited in facta measure, and an exact measure, of the force with which the heart forces the blood through the body of the animal. He fixed transparent tubes to various arteries of living animals, and thus observed, by the height to which the blood rose in them, the force with which it was driven by the heart in the different circumstances examined by Dr. Hales. Sometimes the animal was possessed of its full strength ; some- times its strength was diminished by the abstraction of a deter- minate quantity of blood, or by a variety of other ways which it would be too tedious to describe here. “The effect of these changes on the height to which the blood rose in the tube, on the frequency of the pulse, and upon the whole state of the animal}, are carefully observed, and from them a vast number of useful and curious consequences are deduced. He shows, for example, that profound inspirations and frequent contractions of the lungs increase the velocity of the blood, and that yawning has the necessary consequence of accelerating the flow of the blood through the lungs. He shows lkewise that too great a loss of blood, instead of diminishing, actually increases the rapi- dity of the flow of blood through the arteries. He extracted the whole blood from animals, and substituted in place of it water heated to the same temperature ; but the hfe of the animal was not supported. Thus he showed that the blood, does not act merely as a liquid ; but as a substance of a peculiar kind. His observations on anatomical injections are of great import- ance, and give quite a new view of that subject. The object of anatomists, in injecting the veins and arteries of animals, is to fill them with a liquid, which afterwards becoming solid, may exhibit these vessels of the same size as they possess in the living animal. But. as these vessels are extensible, it is obvious that if the matter of the injection be pushed with greater or less violence than the blood was pushed on in the living animal, the vessel will in consequence be more or less distended than in the living animal, and consequently the capacity of these vessels will no longer be the same as in the living animal. To remedy this inconvenience, Dr. Hales employed, to push on an injection, a column of liquor, which he renders equal in force to that exer- cised by the heart during the life of the animal. Of the amount of this force he had satisfied himself by his previous experiments. This method of proceeding enabled him to judge with much greater accuracy than former anatomists of the capacity of the different vessels through which the blood flows. He measured the diameters of each, and endeavoured to determine by calcu- lation the velocity with which the blood moves in the different vessels. He determined the facility with which different liquids could pass through the blood vessels, by ascertaining the height 1820.} the Rev. Dr. Hales. 167 of the column of liquid necessary to drive each on. These expe- riments led him to observe a very unexpected and surprising phenomenon ; namely, that water cannot be made to pass from the arteries into the veins, though blood passes with freedom ; and that certain places of these vessels which refuse a passage to water allow beer to pass with the greatest facility. He had measured how much the resistance of the viscera and of the principal vessels of the human body could amount to by deter- mining the height of the column of liquid necessary to rupture them ; and he found that this resistance was far superior to the violence to which they had any chance of being exposed. He tried the effects of spirituous liquors, of acids, astringents, emollients, &c. upon the viscera and vessels of animals newly slain. The treatise terminates with a set of experiments on urinary calculi, and on their solvents. These observations and experiments are highly worth the perusal of the physician and chemist. He did not mdeed succeed in his attempts to ascer- tain the nature of these bodies, nor was it possible for him to do so; because destructive distillation, the method which he employed, is not calculated to make us acquainted with the constituents of animal bodies. But his experiments show at least that the previously received opinions upon this subject were erroneous ; and had his notions been taken up and followed out, accurate conceptions respecting these bodies would have been much sooner formed than they were. It deserves to be mentioned, to the honour of Hales, that several chemical papers upon the urinary calculi, some published as late as 1739, hardly throw any more light upon the constitution of these bodies than i: been already thrown upon the subject by the genius of Dr. ales. ‘ The Hemastatics, which constitutes the second volume of the common editions of Hales’s Statical Essays, was translated into French by M. de Sauvage, of the Royal Society of Montpellier, The reputation which Hales had acquired by the publication of these two works successively was so great that the University of Oxford was induced, without any solicitation on his part, to confer on him the title of Doctor in Divinity. This honour is so much the more remarkable because it is not very frequently conferred upon any one who has not been educated at Oxford. Dr. Hales’s experiments having made him acquainted with the effects which spirituous liquids produce upon the blood and the viscera when taken internally, his philanthropy induced him to endeavour to render the knowledge of these effects as extensive as possible. This led him to publish in 1734 a dissertation against the use of spirituous liquids, which he entitled “ Friendly Advice tothe Drinkers of Brandy.” He paints in it the fatal effects of this sort of indulgence in such lively colours as might, one would suppose, be sufficient to deter the boldest drunkard from indulging in his favourite vice. But the unfortu- 168 Biographical Account of [Marcu, nate consequence of this vice is to deprive its victim of the power of reflection. The dissertation of course could not be expected to produce any other effect, except demonstrating the goodness of heart and the patriotism of the author. Similar motives seem to have led him to examine the nature of sea water, the method of rendering it fresh and drinkable, and of preserving corn, meat, and all sorts of provisions fresh during long sea voyages. These experiments, together with many useful instructions to navigators, constituted a work which he published in 1739, and which he dedicated to the Lords of the Admiralty. For this work the Copleyan metal was voted to him by the council of the Royal Society. The reputation which he had acquired by his work on the urinary calculus, and the utility of that work, induced him in 1740 to examine the nature of Mrs. Stephens’s famous cure for the stone, which had just been pur- chased by Parliament. He endeavours to poimt out the importance and efficacy of this remedy, which was then at the height of its reputation. But many years have elapsed since that ephemeral reputation has vanished, and now it is admitted by all that no solvent for the stone can be applied without the risk of fully as great an injury to the constitution as that which it proposes to cure. hree years after, he published a description of the ventilator —an instrument by means of which we may at pleasure renew the air in all places where we have occasion todo so. Itseems unnecessary to give a description of this simple and ingenious machine, as it is sufficiently known, and as a method of renewing the air in the cabins of ships is very generally used in this coun- try, which may be considered as little else than a simplification of Hales’s ventilator. This description of the ventilator was the last separate work peas by Dr. Hales. He was then 60 years of age, and did not choose after that period of life to venture upon long publications. But he inserted a great many interesting papers in the Transactions of the Royal Society. . Of these, it seems requisite only to notice the most important. Dr. Berkeley had brought tar water into fashion as a medicine, and its virtues were highly extolled all over Europe. Dr. Hales was too much of a philosopher to be led away by the enthusiastic encomiums passed upon any medicine whatever. He examined tar water, and pointed out the diseases in which it might be used with advantage, or at least innocently, and the cases in which it would be improper to employ it. Tar water has long ago lost its reputation, and is no longer employed in medicine ; but Dr. Hales’s opinions respecting it ought not to be forgotten, as they show us how far he rose above the prejudices of his age, and the care he took to investigate opinions before he admitted them. In the same year (1745) he pointed out a method of stopping the progress of combustion by covering with a layer of moist earth those buildings through which it was likely the 1820.} the Rev, Dr. Hales. 169 conflagration would pass. This method was carried to Constan- tinople, and enabled the Turks to save one of the finest buildings in that Ottoman capital. Two years before this he had given a method of injecting into ° the abdomen in the case of paracentesis any injection wished for during the very time that the dropsical liquor is passing off. He had been told that a woman labouring under an ascites had been cured by her surgeon by means of an injection of red wine and alum water. This piece of information led him to think of a method of improving the process. His method was exceed- ingly simple. ‘Two trocars were introduced into the abdomen instead of one; and while the liquid of dropsy was running out of one canula, the injection was to be introduced through the other. This process has been for many o_ very much employed in hydrocele, and with the best effects. Its success in ascites is much more problematical. The phenomena of electricity had attracted the attention of men of science during Dr. Hales’s life time ; and in the latter period of his existence, they had acquired a very high degree of celebrity, and were become the fashionable study. It was not likely that they could escape the attention of a man possessed of the curiosity and the sagacity which characterized Dr. Hales. Accordingly we find a paper by him on electricity in the Plilo- sophical Transactions. He remarks that the colour of the electric spark is different when drawn from iron, from copper, and from an egg laid upon copper. Hence he infers that the substance from which the electric spark comes furnishes some part of its own substance to the spark, and thereby occasions the peculiar- ity of colour. Earthquakes were particularly common and dreadful in their effects during the life time of our philosopher. Hence his atten- tion was naturally called to them, and his ingenuity employed, in attempting to account for their existence. He conceived he had found an explanation in an experiment which had been related in his Statical Essays. He had obtained a quantity of nitrous gas by dissolving iron pyrites in nitric acid, and he found that when this gas was mixed with common air, it became red, and the bulk of the mixture was diminished by a volume near! equal to the original volume of the nitrous gas. This experi- ment, which was very imperfectly understood by Dr. Hales, and indeed was not fully explained till many years after his death, he employed to account for the origin of earthquakes. The nitrous gas he considered as an air impregnated with, or consisting of, sulphureous vapours. These vapours in his opinion were conti- nually exhaling from the earth. When they were produced in great quantities, and came to be mixed with pure air, the vacuum ormed by the sudden destruction of the elasticity of so great a quantity of air would, in his opinion, be sufficient to occasion earthquakes. Notwithstanding the wildness of this hypothesis, 170 Biographical Account of [Marcn, the paper contains much curious information, and some facts are to be found in it of considerable interest; as, for example, the information that when a.cannon is fired in St. James’s Park, the glass in the windows of the Treasury becomes charged with electricity. _ Lime water had been proposed as a good vehicle for preserving fish, &c. without salting. This method Dr. Hales examined, and found not to answer. He points out its fallacy in a paper rinted in the Philosophical Transactions, on the Antisceptic owers of Lime Water. The last paper of Dr. Hales which we shall mention contains a description of a method of greatly increasing the rapidity of distillation. The method was to blow up a constant shower of air through the boiling liquid by means of a pair of double bellows. By. this method he shows that a very considerable quantity of sea water may be distilled on ship-board, and sweet- ened ina comparatively short time, and with asmall quantity of fuel. Though the extreme sobriety and regularity of Dr. Hales’s ‘mode of living had preserved his health and vigour till a very advanced age, it was not in his power to resist the effects of time. He died accordingly on Jan. 4, 1761, when he had nearly reached his 84th year. He was buried, according to his ewn request, in his church of Teddington, which he had rebuilt himself a few years before his death. But at the expense of the Princess Dowager of Wales a monument was erected for him in Westminster Abbey. Dr: Hales had been long known to the Princess of Wales, and had been indeed in some measure in her service. To her consort the Prince of Wales, the father of his late Majesty, he was so well known, and was held in such estimation by him, that this prince was accustomed frequently, alone and unattended, to sur- prise him in his cabinet, where he was constantly occupied with the most curious and useful researches. He forgot his rank and his grandeur for the pleasure of enjoying his familiar conversa- tion, from which he derived a fund of information which he eould not otherwise have acquired. After the death of his Royal Highness, Dr. Hales was appointed Almoner to his consort the Princess of Wales. He had made no application for this place, the whole matter had been transacted without his know- ledge, and he could not avoid expressing his astonishment when he heard of his appointment. Modesty indeed was his charac- teristic virtue. Though known and admired by all the philoso- phers im Europe, he received the encomiums that were continually lavished upon him, as if he had not deserved them. The same principle rendered him satisfied with his situation, which he considered as fully adequate to his merits. When, through ‘the interest of his friends, the King had appointed him 2 Canon of Windsor, he employed all his credit with the Princess of Wales to get the appointment cancelled. : 1820.) the Rev. Dr. Hales.’ 171 He was not more ambitious of literary honours. And in 1753 he was named a foreign associate of the French Academy of Sciences, solely on account of his reputation, without any solici- tation whatever on his part. His manners were particularly amiable ; and in the cast of his character he is said to have had a very considerable resemblance to the celebrated Boyle. The sole object ofall his labours was public utility ; and he seems to have had no other ambition than that of discharging his duties to his country and to mankind in general. A single example will be a sufficient specimen of the gentleness and humanity of his disposition.. His hemastatics were not carried nearly so far as his vegetable statics. He assigned the reason of this in a letter which he wrote to M. Duhamel. The tortures, to which he was under the necessity of subjecting the inferior animals, preyed upon his mind so much, that he durst not venture to proceed _ with his experiments, but found it necessary to drop the subject altogether. Dr. Hales was married, and always lived with his wife in the most perfect harmony, but it does not appear that he left any children. Articte II. Description of a Barometer for measuring Heights. By Mr. James Allan. (To Dr. Thomson.) SIR, Erskine, Jan. 26, 1820. Tue following is a description of a convenient barometer for measuring heights, which’ send you for insertion in the Annals of Philosophy. This barometer is of the recurve kind. The turned up part is a piece of wide-tube, in which an iron float is to be put to swim on the top of the mercury to prevent its convexity. ‘The propor- tion of this to the long tube must be accurately ascertained. We shall consider it to be as 12 to 1. A scale of inches, as in other mountain barometers, is to be attached to the top of the tube on the one side, by which to mark the positions of the mercury in the column of suspension. ‘Then from the proportion of the tubes being to one another as 12 to 1, for every 12 parts the mercury falls on this scale, it will rise one part in the turned up tube ; so that the column of suspension will be shortened 13 parts. Hence, when the quantity of fall on the scale is correctly found, it is only necessary to add one-twelfth part of itself to it to know how much the column of suspension is shortened. ‘ This, however, may be found more easily by means of a scale, 172 Mr. Allan’s Description of (Marcu, which we are now going to describe, which may be put in place of the other. We have supposed the tubes to be to one another as 12 to 1, and have found that for every 12 parts the mercury falls on the scale, the column of suspension is shortened 13. If then an inch be divided into 13 parts, when the mercury in the long tube falls through 12 of these, the column of suspension will be shortened a full inch. Hence if a scale be made use of, whose large divisions are equal to +3ths of an inch, mstead of real inches, these nominal inches and their subdivisions will indicate with accuracy the number of true inches and correspond- ing parts of inches, by which the column of suspension is shortened. In order that altitudes may be found without logarithmic tables, a scale of the kind we are going to describe, may be attached to the other side of the barometer. This scale must be so divided, as to show with accuracy the quantity of fall cor- responding to certain determinate altitudes. The method of finding the size of the spaces for the altitudes required is this. Supposing that it is designed to make the large divisions of the scale to correspond to 100 fathoms, and that we commence the calculation from 30 inches of mercury downward, we seek the logarithm of 30, the decimal part of which is 0-4771, from this we subtract 100, and there remains 0°4671, which we find to be the decimal part of the logarithm of 29°32, this we subtract from 30, and there remains 0°68 of an inch for the size of the first space. Next, from 0-4671 we subtract 100, and there remains 0°4571, whose natural number is 28°65, which, when subtracted from 29°32, leaves 0:67 of an inch for the size of the second space. In this way are all the divisions and subdivisions of the scale to be formed. In finding the spaces above, that I might be able to show the method more simply, I have made use of logarithms of four places of decimals only, and the size of the spaces is for that reason not correct; but, in calculating for the scale, tables extending to eight or nine places of decimals will be required, as the utmost accuracy is necessary in its construction. It must be kept in view that the spaces are not to be taken offa scale of real inches, but a scale of nominal inches, the same as is second described. I come now to show the method of correcting for the tempe- rature of the mercury, in making use of the above scales. If the scale of real inches is used, this is done in the common way. If the scale of nominal inches is used, one-thirteenth of itself is to be added to the quantity that is to be taken from, or put to, the length of the column of mercury, because each of the nominal inches is one-thirteenth of an inch too little. If the scale that is divided so as to indicate certain determinate altitudes, is used, a slide which is to extend across both scales is to be screwed up or down to the place where the mercury should be if the 1820.] a Barometer for measuring Heights. 173 temperature was proper. This place is easily found on the scale of inckes ; so that by screwing the slide till the one end come to the proper place on this scale, the other end will of course take the right position on the scale for determinate distances. By adjusting the slide at the foot and top of the mountain, and counting the divisions between its positions, the approximate altitude of the mountain is obtained. As the finding of the true altitude does not depend on the barometer but the approximate only, it is not necessary for me to say any thing about that, as the method is given in every work in which mensuration by the barometer is treated of. I shall conclude this letter by making a few remarks concern- ing the most favourable times for measuring with the barometer. Calm weather is indispensably necessary for this operation, beeause air in motion has not the same perpendicular pressure as when at rest, but its gravity diminishes as its velocity increases. Hence, if a stratum of air of the altitude of any mountain moves with such a velocity as to cause its perpendicular pressure almost to vanish, then the column of mercury, being supported in no sensible degree by that stratum, but by the atmosphere above it, will suffer no apparent change in being carried from the foot to the top of the mountain. Clear unclouded weather is also necessary, for clouds by their shadows and different temperature disturb the regular progression of the atmosphere. Mr. Greato- rex, in an account which he gives in the London Philosophical Transactions for the year 1818, of a measurement he made of the height of Skiddaw, ascribes the erroneous results he obtained by the barometer wholly to the effect of clouds. Beside the above, there is still another circumstance worth attending to, which is the height at which the barometer stands ; when it stands high and continues steady, then is the most favourable time for measuring with it. When it is low, it is unfavourable ; for the fall may be produced by some approaching wind, giving a buoyancy to the atmosphere before it, or by winds in the higher regions, which circumstances would disturb the geometrical progression of the atmosphere, and hence render a correct measurement impossible. If all these favourable circumstances which I have mentioned are possessed, and a good barometer used, the results, at the very least, are equally to be depended on as those obtained by trigonometry. Yours, &c. James ALLAN. 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(a{? : So o|}8)s ‘ 55| 52 8 3 3 : a ex r—) . e won i} 5 i= . wy = 3 | 2 >. =] 5 S r- |? : , = 2B = - z o 3 o Pa = § hl oak F Te | RS £4| a Fe ——$——. § ‘NIVU ‘SaNIM "YATHLVAM | “WUAHL §.XIS “URLANOUVA “6181 Ss i) a “u0yPoo}g soup ap Ag S “GIGI 0a t ay7 ws ‘acrysyloT te MOP Many 70 yday NEST EOEDY poorBogo.40990 fy D fo synsay “ TI] @rmyy ~ ast m4 > 1820.] kept at New Malton, Yorkshire, for 1819. 175 ANNUAL RESULTS. Barometer. . Inches. Highest observation, Sept. 21. Wind, N. .......... 30°400 Lowest ditto, Jan. 25. Wind, 8.E. boisterous........ 28-400 Range of the Mercury .. cos. esse ccnsecenecere ves 2000 Mean annual barometrical pressure ....... ipa cise le 29-598 Greatest range of the mercury in January. .......... 1-910 Least range of ditto in May. ....s0.esseeeeceeecves 0:570 Mean annual range of ditto. .......... 5 a tatea alas Sia oy ES Spaces described by ditfo's yi fH eel ete ee 75°550 Total number of changes in the year. ........-.s00. 177-000 Six’s Thermometer. Greatest cbservation, Aug. 14. Wind, W.......... 77-000° Peoee wists, Dec. a)... Wind We -socee se tt ep eet eee 9-000 Range of the mercury in the thermometer. ......... . 68-000 Mean annual temperature. .......... ‘abrir the tiie tire 47-773 Greatest range in December........ Sie aie Soe te te 46-000 MRE StH UILEO TEPC EATON > here one's vices ee erates Shee a eee ed 24-000 REAM al TANCES te Cw ee ns +s ak neeicsisle'es 31°333 Winds. Wore de Masts 2) 2284 F944 SI Ope HOPI Pd J 67 WNorth-Hast and South-Hasti ii Oe ee O OLS 75 Southand’ West’... ees eS OOS 27 LONE OL i 93 South-West and North-West. .......c.0.. cece dees 102 eee? Pe aa yk ed 20) BOR LOT ae 28 Rain, &c. Inches. Greatest quantity (including snow and hail), in Dec... 5°50 Beret itto, in Anifust, £5 2 200 bo od areeeme poled 1-25 Total amount for the year... 686 OSE eee wile does 30°85 REMARKS. The mean and the maximum of the barometrical pressure for the last two years, are nearly alike, andthe number of changes in the direction of the column are exactly so; although the nme described in the former year exceed those of the one just elapsed by 34 inches. the mean temperature is about half a degree below that of 1818, and the ditierence between each month is rather unusual. The first five months and the seventh in 1818 were on an average nearly 4° colder than the corresponding ones in the last year ; _ but the others were proportionably the reverse. The amount of rain, &c. is two inches less than in 1818. The principal features of the year are the uniform and long j 176 Col. Beaufoy on the Going of a Clock [Maren, continued heat and dryness of the summer season, and the early commencement of winter, which to ‘the present time has continued with excessive severity. New Malton, Jan. 4, 1820. JAMES STOCKTON. ee ArTIcLE IY. On the Going of a Clock with a Wooden Pendulum. By Col. Beaufoy, F.R'S. (To Dr. Thomson.) MY DEAR SIR, : Bushey Heath, Feb, 7; 1820. To determine what reliance could be placed on the going of a clock with a wooden pendulum, I fitted one of my monthly regu- lators, beating dead seconds, and whose motion continued while winding up, with a straight-grained cylindrical deal rod ; but being dissatisfied with the irregularity of the rate, I was on the point of rejecting this, when, from the circumstance of the clock becoming much out of beat, I concluded the great source of error might probably proceed from the warping of the wood. I, therefore, caused the intermediate portion of the deal, about an inch below that part where the watch spring which suspends the pendulum is, fastened to the upper part of the bob, to be reduced from a cylindrical to an eliptical shape, the transverse, or longest diameter being parallel to the back of the clock ; this alteration so much improved the going, that 1 am induced to trouble you with a table containing the rate for 12 months, and to remark that the rod was perforated in the centre for the crutch to pass through, and a brass eye inserted to prevent the wearing away of the wood. To render.the. pendulum steady, it was hung independent of the frame that supports the clock ; and the bob, inlieu of being screwed to the rod, was permitted to rest upon a divided nut, turning on a fine screw, attached to the lower extre- mity of the rod, and which answered the twofold purpose of supporting this weight, and regulating the pendulum. The advantage of permitting the bob to remain unconfined to the rod is, that the expansion of the bob upwards has a tendency to counteract the expansion of that spring by which the pendulum is hung downwards, and of, therefore, preserving the same length. By examining the table, it will be found that the accuracy of the simple pendulum described is little inferior to the compound one, known by the name of the gridiron pendulum ; and when it is also considered that the latter costs 12 guineas, and the rod not as many pence, the variation of the going bears so small a pro- portion to the difference of price, that it will, generally speaking, be sufficiently accurate for most purposes. I remain, My dear Sir, yours, very sincerely, Mark Beavroy. 1820.) with a wooden Pendulum. 177 Table containing the Rate of a Clock with a wooden Pendulum. Clock fast or| Differ-| Dail Clock fast or|Differ-} Dail Date. slow. ences, aaa | Date. slow. ences. Sais 1819. Aug. 3/—1’ '55-09”| 1-29”| —0-43” Jan, 31/—0' 10:40’) — — Tj—1 58°41 | 3°32 | —O°83 “eb. 6,—0 02°07 8°33" | —1°39"' 10;—2 O1°05 2°64 | —O°S8 10,—0 03°37 544 |—1°36 14/—2 03°39 |} 2°34 —0°59 13; —O 07°91 4°54 |—1°51 21/—2 O7°80 | 4:41 —0°63 20:—0 18°55 |10°64 |—1°52 *25/—O0 10°88 | 3:08 | —O°T77 25|—0 23-47 | 4-92 |—0-98 26/—0. 09:75 | 1-13 | +143 March 4—0 30°45 6°98 |—0-99 27;/—O 69°53 0°22 | +091 9\—9 38°00 | 7:55 {—1°51 28)—0 09°83 0°30 | —0:30 14;—0 46-00 | 8:00 |—1-60 31/—0 OT:14 2-69 +0:89 18}-O 50:17 417 |—1:04 || Sept. 2/—0 07°95 0-81 | —0-40 22}/—O0 5067 | 0:50 |—0°13 6|—O 06°54 | 1-61 | +0°40 24\-0 50:23 0-42 1+0°21 9|—0 08:55 2-21 —O'T4 26'—0 50°32 | 0-07 |—0:03 13}/—Q 08-84 0:29 | —0°07 29'\-—O 50°10 | 0°22 |—0-:07 17j/—O 11°67 2-83. | —O°TE April 1/—O 52-02 1-92 |—0°64 19)—@. 10-33 1-84 +0°'6T 3)\—0O 53°86 1°84 |—0 92 21-0 10°75 0-42 | —O°2k 5 —9 54:20 | 0:34 |—O°17 23)—0 08°55 2°20 | +1°10 71|—O 54:34 | 0°14 |~-0-07 Oct. J}—O0 20-05 |l1-50 | —1-44 10;\-O0 55°05 | O-TL | —0-24 4'\-O0 18-01 2-04 + 0°68 15-0 57-22 217 |—0°43 Si\—O 18°25 0-24.| —0°05 27\—1 08:06 {10°84 |—0-90 12)-—-O 21°38 3°13 —1:04 29'-1 08-73 | 067 |—0-34 14}—O 23:57 | 2:19 | —1-09 May Ij—-1 08-61 0-12 |+0-04 16,—O 24-03 0:46 | —0-23 4\—1 -06:07 2°54 |+0°85 TSj=6 24°10 0:07 — 0:04 U—-l 04:37 1°70 |+0:57 22;/-0 21°90 2:20 + 0°55 9i—-1 03°77 0-60 |+0°5 27;—0O 18:58 3°32 + 0°66 12j—-I 01-40 2:37 |+0:79 Nov. 3/_0 16°60 198 | +028 14/—-1 01-70 0-30 |—O-15_ 6|/—O 17-22 0°62 | —0-21 1Wj—-1 00-15 1°55 |1+0°52 10'/-0 16°50 0-72 +018 22)-O0 58°70 145 |+0°29 12/—O 15°66 0°84 +042 23)—1 01:64 2°94 |—0-49 21|-0 13556 0:10 +9-01 June 5\—-1 0081 0°83 |+0:10 23'—0 13°53 2-03 +102 7j—1 02-00 1:19 |—0-59 726/41 02°58 — — 9-1 02°85 | 085 |—0-42 Dec, 3)+0 59-20 |} 3:38 | —0-48 16;—1 04:98 | 2:13 |—0°30 §1+0 57°53 1-62 } —0*32 19/—-1 07°96 | 2:98 |—0-99 14}+0 57°08 | 0:50 | —O°17 2ij—-1 10-62 2-66 |—1°33 13}+0 57:87 0:79 +0°49 ~ 30/—-1 19°32 | 8-70 |—0-97 22\+0 47-60 }10-27 | —1-14 July 3)-1 22-70 | 3°38 |—1:'13 ; 24/40 AT-16 0:44 | —0-22 Til 29/72 7-02) |—1 75 27;}+0 AT-AT 0-31 +010 17-1 43°54 |13'82 |—1-38 30/+0 438-07 0°60 | +0°20 49\—-1 45:50 | 1-96 |—0-98 21)+0 48:74 | 0-67 | +0-67 22\-1 50°68 | 5:18 |—1-73 1820. 23)-1 50-91 | 0-23 |—0-23 Jan. 3}/+0 49°11 O37 | +0°12 25)-—1L 5305 | 2-14 |—1-07 5|+0 48°45 | 0-66 | —0-33 26/—1 54:44 | 1-39 |—1-39 8}+0 49°16 | O71 | +024 28)—1 54:38 0:06 |+0:03 15/+0 48 84 0°32 | —0°'05 29/—k 54-90 0°52 |—0°52 22)+0 4594 2°90 | —O-41 3Ij—-1 56-58 1:48 |—0-14 31;/+0 37°72 8°22 ~— 0°96 ae = cael * Aug, 24, clock put forward two minutes. + Noy. 25, clock taken to pieces and cleaned. Vou. XV. N° UI. M 178 Extracts from the Persian Work called [Mancn, ARTICLE V. Yranslated Extracts from the Persian Work called “ The Book of Precious Stones,” by Mohammed Ben- Manssur. Trans- lated into German by Mr. Joseph Von Hammer. THERE can remain little doubt but that the knowledge of precious stones first came to us with them from the East; even the names of most of them do not differ from those in the coun- tries where the mines of them are situated; and yet nothing has been made known from these sources except some specimens of the Arabian work of Téifaschi, which Ravius published in the year 1784, at Utrecht, and some passages in Bochart’s Hiero- zoicon, treating of precious stones. These extracts will, there- fore, not be unwelcome, particularly to lovers of mineralogy and precious stones, as they not only contain the original Persian names, but also the very important classification ; from which it appears that the fact, that rubies, oriental topazes, and sapphires, elong to one and the same class, namely, that of the Jakut, (which is a modern discovery in Europe,) has long been known to the inhabitants of the East, and that they have been acquainted for centuries with the mode of determining the specific gravity. The author composed his work in the seventh century of the Hegira (in the 13th of the Christian era) for the Emperor Abu Nassr Behadirchan, of the family of Abbas, in two books, the first treating of precious stones, and the second of metals. Considering the ideas that have prevailed in the East for thousands of years, it will not be surprising that among the former the pearl takes the lead. Every chapter regularly consists of four sections, the first of which treats of the external and visible qualities, the second of the mine, the third of the value, and the fourth of the mternal mystical qualities. Our extracts are confined to the first two sections of each chapter; as the value set on precious stones in Asia in the 13th century could, at the most, be a useless gratifi- cation of the curiosity of amateurs, and an enumeration of their secret, fabulous, and talismanic properties could be of no kind of use to real science. Cuap. I. Sect. 1. Of the Classes of Pearls.—Pearls are called merwarid (hence the Latin margarita), or lulu; this last name is usually given them when pierced. They are divided into various classes, according to their water and lustre. 1. Schahwar, i. e. Royal pearls, the brightest and purest. 2. Durr, the common pearls, likewise called choschab, nedschmi, and ojun. 3. Schekeri, 1. e. sugax pearls, are of a red and yellowish colour. 4. Benins, yellow-white. 5. Serdi, the yellow-red. 6. Kebudi, the blue- 1820.] “ The Book of Precious Stones.” 179 white. 7. Rossassi, those clouded with a kind of lead colour. 8. Surchab, those watered with red. 9. Stahab, those watered with black. 10. Schemii, the wax-coloured green and yellow, and not transparent. 11. Rochami, the- marbled, dark, not transparent, and without lustre. 12. Chusckkab, those of dull water, in contradistinction to those called choschab (mentioned above), i. e. of pure transparent water. With respect to their form they are divided, 1. Into the mudahredsch, those quite round. 2. Ghabni, those of the egg shaped. 3. Aakid, half flat and halfround. 4. Scheldschami, turhip-shaped. 5. Adsi, lenticular. 6. Settunt, in the form of an olive. 7. Schairi, shaped like a barley corn. 8. Sez/¢, formed like a tail or train. 9. Schemi, in the form of a taper. 10. fokai, in the form of a Can. 11. Nimrui, hemispherical. 12. Mussarres. With respect to their size, they are divided into 15 classes, according to the number of the sieves through which they are passed, and of which one has always larger holes than another. The pearls of the first sieve, which has the smallest holes, are called: 1. The twelve hundred ; because 1200 of them weigh a miskal. 2. Those of the second sieve, the five hundred. 38. The four hundred. 4. The three hundred and fifties. 5. The three hundreds. 6.The hundred and eighties. 7. The hundred and seventies. 8. The hundred and sixties. 9. The hundred and fifties. 10. The hundred and twenties. 11. The hundreds. 12. The eighties. 13. The seventies. 14. Fifties. 15. The forties, 40 of which weigh a miskal. Sect. 2. Of the Pearl Fisheries.—The best are at Serendib (Ceylon), and in the gulph of Persia at Bahréin, Kisch, and Scharek, but the Arabian are less valued than the Indian; their colour and quality depend on the bottom of the sea where they are produced ; they become dark in a black mud, and yellow in a shallow sea. The pearl oysters drawn out of the sea sometimes move very quickly, and sometimes not at all. Crap. Il. Sect. 1. Of the Properties of the Jakut.*—It is of six different kinds: 1. The red. 2. The yellow. “3. The black. 4. The white. 5. The green, or peacock colour. 6. The blue, or smoke- coloured. ‘The first, namely, the red, is again subdivided into six kinds: 1. Wirdi, the rose-coloured. 2. Erghiwani, the purple-coloured. 3. Behremazii,+ the yellow-red. 4. Lahmi, the flesh-coloured. 5. Sumaki, the porphyry-coloured. 6.-Rem- mam, the pomegranate-coloured. ‘The second kind, the yellow, * Itcannot be doubted that the jakut is our sapphire (télésie), and it is astonish- ing that the orientalists had already, at that time, « proper idea of this stone, for which we ave indebted to the latest researches, which particularly coincides with the division into four classes: the red (rubis d’orient), yellow (topaze d’orient), blue and white. : + Behreman is an Indian flower, and, as some will have it, the blossoms of the Carthamus. mM 2 180 Extracts fromthe Persian Work called [Marcun, has three divisions: 1. Mischmischi, the apricot-coloured. 2. Narendschi, the orange-coloured. 3. Kahi, the straw-coloured. The third and fifth kinds (the b/ack and green), and the second and fourth kinds (the yellow and white), are one and the same. The sixth class (the blue) consists of four kinds: 1. Asrak, the light-blue. 2. Ladschiwerdi, the azure colour. 3. Nil, the indigo-coloured, each of which’has several subdivisions. Some divide the jakut into four classes: into the red, yellow, dark, and white, as they count the peacock-coloured, and the blue among the dark. The jakut cuts all stones, except cor- nelians and diamonds,* and can only be cut by the diamond. Of other precious stones, only the Laa/, of Bedachschan, has the lustre of the jakut ; it is harder than all other stones, and cool in the mouth ; the red jakut appears white in the fire, and again attains its former colour when taken out of it. When it is cut, it is called memsuh, and in its original state adschemi. There are six kinds of precious stones similar to the red jakut. 1. The Laal. 2. The Bidschade. 3. The Benefsch. 4. The Kerkend. 5. The Kerkin. 6. The Kuser. The kerkend is of a dark-red colour, and the kerkin reddish-black, and transparent’ in the sun. The kuser has all the colours of the various kinds of the jakut. The difference between the jakut and the stones that resemble it is, that it scratches them, is heavier, and bears the fire. Thus the white Jakut weighs more than the crystal, which it often resembles. Sect. 2. Of the Mines of the Jakut.—On the island of Saha- ran, which is 62 farsanges in diameter, and lies about 40 farsanges behind the island of Ceylon, is a high mountain called Sahun, in which jakuts of all colours are found. In the year of the Hegira, 669 (A. D. 1270), a mine of Jakut was discovered to the east of the village of Tara, in the third climate, and in the same latitude as the Canary Islands, and half a day’s journey from Cairo, though some people assert that there is,no jakut mine except the mountain of Sahun. Cuapr. IIIl.—Of the Emerald. (Semerriid.) Sect. 1. Of the Properties of the Emerald.—tit is divided according to its colour. 1. Into the subabi, grass-green. 2. Rihani, basilisk-green. 3. Sulukz, leaf-green. 4. Sindschart, dirty-green. 5. Kerasst, euphorbia-green. 6. Ass?, myrtle- green. 7. Sabuni, soap-green. The grass-green is of a beautiful light colour, like the green worms which are often seen in the grass ; it is the lightest, as the soap-green is the darkest. The emerald, according to the degrees of its purity, is also divided into the bright polished (satkali) and the dark (sudmani). The first reflects every thing that is held before it like polished steel, * This statement of its hardness and weight characterizes it with the most preci- sion. Though the oriental carnelian is uncotamonly hard, and difficuit to polish, this far too high estimate of its hardness isa singular but pretty general error, 1820.] “ The Book of Precious Stones.” 18} while the latter does not bear the fire so well. The difference between the emerald and stones resembling it, as the jasper, the green /aal and mina (green glass), consists in the polish. The oblong emerald is called kasaba (staff), and several pieces of emerald joined together by mina (green enamel), are called astar. Sect. 2. Of the Mines of the Emerald.*—On the borders of Negroland is a pit of emeralds which still belongs to Egypt, where they are dug first out of talc, and then out of a red earth. The soap-green emerald is also found in Hedschas, and it is on that account called the Arabian. Cuap. 1V.—Of the Chrysolite. (Seberdsched.)+ Sect. 1. Of the Properties of the Chrysolite—Abunassr Farabi, and many other learned philosophers, do not consider it to be of any particular species, but a kind of emerald: it is more beautiful and clear, and is divided into three classes; namely, 1. The dark-green. 2. The middle-green. 3. The pale-green. Sect. 2. Of the Mines of the Chrysolite.—I\t is dug out of the same mines as the emerald, and seems to be composed of the same materials, but less finished.{ Tez/aschi says, that in his time no chrysolite was dug ; the rings which are seen of them come from Mauritania, and tradition considers them as fragments of the treasures of Alexander, who sought in the deserts of Africa for the fountain of life. After he had penetrated with his army into the land of darkness, in which flows the green fountain of life, it is said that the gravel under their feet (green, with the reflection of the fountain of life) was called the pebbles of repentance (hassbaen-nedamet). When they returned to the light, this saying was confirmed; for both those who had gathered none of the pebbles, and likewise those who had gathered some, repented, the first, because they had nothing, the second, because they had only chrysolite, and which was on that account called the pebbles of repentance. Cuapre. V.—Of the Diamond. Sect. 1.—There are seven kinds of it. 1. The white-transpa- rent. 2. The pharaonic. 3. The olive-coloured, the white of which inclines to yellowish. 4. The red. 5. The ereen. _™ Itis very interesting to learn, with some degree of precision, the oriental mines of the emerald, to be able to explain where the Greeks and Romans, of whom we have indubitable works in emerald, procured this stone, as they could not be acquainted with the only place where they are now found, the valley of Peru. From the latest accounts.of the Frenchman, M. Caliot, who had been sent by the Pascha of Egypt tdlook for the ancient emerald mines, he has beea so fortunate as to discover them in the neighbourhood of the ted Sea, which pretty nearly coin- cides with these accounts, + Ravius merely translates the Seberdsched as Smaragdum minoris valoris in his Latin treatise, because Téifaschi, as appears from the text, merely considers it as ‘a kind of emerald, ¢ The difference between the emerald and the chrysolite, both in their extermat as well as chemicat characters, is now sufficiently known, and also that according. 40 modern travellers, the chrysolite is found in Syria. ; 182 Extracts from the Persian Work called [Marcn, 6. The black. 7. The fire-coloured. The first two kinds are the most common, the others more rare, and that which is quite polished, the most seldom found. It does not break on the anvil under the hammer, but rather penetrates the anvil. In order to break it, it is laid between lead, which is struck with the hammer, and then it breaks. Others enclose it in resin, or wax, instead of lead. The diamond has an affinity with gold, ‘small particles of which are attracted by it; it is also much sought for by the ants, and covered with them, as if they would devour it. In India, where it is very highly esteemed, the exportation of it was formerly prohibited. Sect. 2. Of the Diamond Mines.—In the eastern part of India is a deep ravine inhabited by serpents,* where diamonds are produced. Some people suppose that it is found in the jakut mines. Cuap. VI.—Of the Cat’s Eye. (Ainol-hurr.) Sect. 1. Of the Properties of the Cat’s Eye.—It is a brilliant transparent stone, which appears to the spectator like the eye of a cat seen in alight place. If you turn the stone, this bright focus also turns ; and if light falls on it, it plays in waves, which move the more, the stronger the hght is which falls on it ; if you break a cat’s eye into pieces, you find the same focus in every one of them. Sect.2. Of the Mines of the Cat’s Eye.—It is affirmed that the cat’s eye is found in the jakut mines, and formed of the same matter. Cuar. VII.—Of the Spinell. (Laal.)+ Sect. 1. Of the Properties of the Spinellus—It is of four different kinds: 1. Red. - 2. Yellow. 3. Violet. 4. Green, hike the emerald. Sometimes the same stone is half green and half red. The red is of eight kinds: 1. Geschdimegi. 2. Piasegi. 3. Temert, the date-like. 4. Lahm, the fleshy. 5. Anabt, the dove-like. 6. Bakami, having the colour of Brazil wood.t 7. Ldrist, the stone enoch. 8. Ekheb, the dark. The gesch- dimeg: is remarkable for its pleasing colour and lustre. The praseg? has derived its name from the village of Piaseg.. The flesh-like is dark-red. The gradations of the spinell are various, and jewellers know very well that there is sometimes no differ- ence in the colour between the spinellus, the garnet, and the coloured crystal. _The difference consists in the superior hard- * Vere the well-known fable is mentioned, out of the thousand and one nights, of the birds which fetched up pieces of meat to which the diamonds stuck. . + itis not to be doubted that lead is our spinellus, which is found in all shades of red, and several of violet and bronze, as also grecn, like pierre de Mahomet: as yellow, or under a denomination of red, the author, perhaps, took the hyacinth, which has much resemblance, both in its brilliancy and the manner of treating it for the purpose of polishing. de ~ M. Von Hammer has here the word Pernambukartige, which it seems diflieult to translate otherwise; yet Brasil was not known to the Persian author, 1820.] “ The Book of Precious Stones.” 18S ness of the spinellus, which is not broken on the anvil, while the coloured crystal, when held to the sun, appears white. The Jaal had its name from Bedachschan, not so much because it is found there, as because it is sold in that province. Sect. 2. Of the Mines of the Spinell.—At the time of the Cali- hate of the Abbassides, a mountain at Chatlan was rent open y an earthquake, where there was found the laal of Bedach- . schan bedded in a white stone. It is very hard to polish, and it was a long time before it could be smoothed,* till it was at length accomplished by means of the gold marcasite called ebrendsche. Smaller stones are found in the bed round a large one, like the seeds of a pomegranate. The miners call this bed of the spinell maal. There were found in the mines first red, then yellow laal, and it belongs to the kinds of the zakut. Cuap. VIIl.—Of the Turquoise. Sect. 1. Of the Properties of the Turquoise (Firuse).—It comes I. From Nischabur. 2. From Ghasna. 3. From Irak. 4. Ker- man. 5. From Chowaresm. The first is the most valued, om account of its hardness, purity, and durable colour. This has seven kinds: 1. Abu Ishaki. 2. Esheri. 3. Suléimant, a milky and sweet stone. 4. Sermuni, with golden spots. 5. Chakt, sky-blue. 6. Abdol-medschidi, beautifully coloured, but soft. 7. Andelibi, a little milky. The turquoise is bright or dull, according to the weather ; + and is larger in rainy days than in fair. One kind of it becomes ofa more beautiful colour in oil, £ but then loses it again. Jewellers call it mescha; that of two colours is called ebresch. The turquoise is also similar to.a kind of green and blue enamel. According to the time in which it was dug up, it is divided into the old and new mines, of which the new change the colour.§ Sect. 2. Of the Mines of the Turquoise.—It is found in those plates after which it is called; the most beautiful and richest mines are at Nischabur, where that called after Abu Ishak is the most beautiful, and the andelibi the faintest. Cuar. IX.—Of the Bezoar (Pasehir) and other. Animal Stones. Sect.1. Of the Properties of the Bezoar.—It is of two kinds. = 1. The animal. 2. That found in mines. The latter is divided __* The spinell is extremely difficult to polish, which can only be effected by oif of vitriol on a copper-plate. And it is very remarkable that the author mentions, instead of the oil of vitriol used by our Japidaries, the marcasite (iron pyrites), from which the oil of vitriol may be produced. _ + These are probably limestone coloured by vitriol of copper. ft The blue of the turquoise is in reality of so delicate a colour that the influence of the light on a bright or gloomy day seems to cause a striking change in it. § Some turquoises frequently change the shade of their colour, which probably is caused by their inferior hardness aud porosity, and from the effects of acids, or imbibing of oily particles: thus in a-ring with four blue turquoises one turned green after an illness of its wearer. ; 184 Extracts from the Persian Work called [Maren, into: 1. The yellow. 2. The green. 3. The dust-coloured. 4. That spotted like a lizzard. 5. The whitish, spotted with gold spots. They make of it chessmen, draughtsmen, handles for knives, and the like. If you throw the green bezoar into the fire, it turns black witheut being burned; the inhabitants of Kerman call it muchati scheitan. It is the contrary with the animal bezoar ; it is likewise sometimes green, sometimes yellow, some- times of a dust colour, may be easily powdered, and assumes a white colour when it is powdered on the stone. It is divided into the cow bezoar (bakarz), and into the sheep bezoar (schatz). The former is a soft yellow stone; the latter, green and soft. It is very often counterfeited ; the real may be distinguished from the false, as the former will not take a mark of fire, as its colour does not fall into a blueish, as it has no dots, and, when rubbed, gives off a white colour. Sect. 2. Of the Mines of the Bexoar.—It is found on the borders of India and China, as also between Mossul and Dsche- strei Ben Omer. It is said that the animal bezoar is produced in China in the eyes of the stags, in which the exhalations of serpents, which they have devoured, precipitated by the water, are said to be condensed into bezoar. The sheep bezoar is said to be produced in the stomachs of some sheep on the frontiers of Persia. Cnuar. X.—Of the Cornelian (Akik). Sect. 1, aa the Properties of the Cornelian.—It has seven kinds: 1. The liver-red. 2. The rose-red. 3. The yellow.* 4. The white. 5. The black. 6. The blueish. 7. That of two colours. Though a hard stone, it is much used for engraved seals. Sect. 2. Of the Mines of the Cornelian.—It is found in Sanaa and Aden, in Yemen, on the frontiers of India and Rum, and in the neighbourhood of Bassra. Cuap. XI.—Of precious Stones resembling the Jakut, viz. 1. The Benefsch+ (Violet). 2. Bidschade (Garnet). 3. Badendsch. Sect. 1. Of the Properties of the Benefsch.—It is of four different kinds: 1. Madeni, of a pure bright transparent red colour, quite similar to the red jakut; so that if itis strung with the jakut upon the same thread, the best judges can scarcely distinguish them. 2. Ruthi, garlic. 3. Benefschschi, blackish- red. 4. Istasescht, of a hight-yellow colour. All kinds of the benefscht have an affinity with the laal, but the benefsch inclines more to blue than the laal. * Yellow is called serdin Persian; and here, and not in the city of Sardes, we are to look for the origin of the name of the sardonyx. + Benefsch, Bidschade, and*Madendsch, are certainly only different shades of the garnet, and may probably be the violet (almandin), the dark-red, and the ycHlowish-red oriental garnet; namely, that of Ceylon and Syria. That their spe= tific gravities are very different is well known. f Ravius translates Benefsch by amethyst, as falsely as be does jakut by hyacinth, 1820.] “The Book of Precious Stones.” 185 Secondly, Bidschade, the garnet, is a red stone, of pure water, which often loses its lustre when worn in the dress,* and which is distinguished from the jakut not only by its inferior weight, but also by a greater degree of warmth, the jakut, when taken into the mouth being cold, and making it moister, while the contrary takes place with the garnet. Thirdly, the madendsch, or madebendsch, is a very red stone; it is quite similar to the garnet, but its red inclines more to black, and it is lighter in weight. It*has no lustre till it is cut deep from below.+ Sect. 2. Of the Mines of these Stones.—The benefsch is found in the mines of the spinell ; the garnets and raadendsch (made- bendsch, or madenidsch) are found on the frontiers of Bedach- schan, and brought to Cachemire, about ten days’ journey off, which has given rise to the erroneous supposition that there were mines of them at Cachemire. The garnet has a division like the laal, and is found in the mountain of Sahun, where there are also jakut mines. When they come from the mines, they are dark, and without water, and are not bright and transparent till they are cut. Cuav. XII.—Of the Onyx (Dsches?). Sect. 1. Of the Properties of the Onyx.—There are several kinds, as: ‘1. Bakrawi. 2. Habeschi. 3. Anebi. But they are classed according to their colour: 1. Into the white. 2. Into the black. 3. Into the red. 4. Into the particoloured. The bakrawi has three layers ; the first, red, and not transparent ; the second, white and transparent; the third, transparent, like crystal. The habeschi has likewise three layers, two dark, and a white one in the middle. The onyx is the hardest stone after the diamond or jakut, and is about the same weight as a corne- lian. Some onyxes are striped, others not; in others, the stripes are interrupted ; so that they form singular figures. _ Sect.2. Of the Mines of the Onyx.—Though the onyx is found in several places, the most esteemed are those found on the frontiers of China and Arabia. Cuap. XIII. Of the Magnet. Sect.1. Of the Properties of the Magnet.—There are four kinds of the magnet: 1. The zron’ magnet, commonly called the iron robber, ahenruba. 2. The gold magnet. 3. The silver magnet. 4. The tin magnet, which attracts gold, silver, and tin. The magnet loses its power in oily substances, but increases it when wit into blood, gold, or vinegar. The silver magnet is a white ight stone, which swims on water, attracts silver, and is com- ° As they have little hardness, they soon become dull. + { isalso usual among us to cut garnets of a dark colour hollow, or to lay foit onder theta, 186 Extracts from the Persian Work called [Mancn, monly called hadschrol-bokur, i. e. cow’s-stone. The gold magnet is a pale yellow stone, which attracts gold, and the tin magnet is a heavy sinking stone, which attracts tin. Sect. 2. Of their Mines.—They are found in Arabia, India, and other places. ; Cuar. XIV.—Of the Senbade.* (Query Spar?) (German Spath?) Sect. 1. Of the Properties of the Spar.—tt is a hard stone, which polishes iron and steel. It is distinguished from stones which resemble it by its hardness, which is next to that of the diamond, which alone scratches it. It is either reddish or blueish. Sect..2. Of the Mines of the Spar.—It is found in many laces, as in India, Zanguebar, Siwas, Kerman, Nubia, and thiopia. The best comes from Nubia and Siwas. Cuar. XV.—Of the Malachite (Dehne). Sect. 1. Of the Properties of the Malachite-—The malachite is a green stone, which has the colour of verdigrease, with red and black spots. Some persons affirm that in Turkistan a red malachite, of the colour of the red jakut, is produced. The dehne is of five kinds: 1. The leek-green. 2. Basilisk-green. 3. The black-green. 4. The white-green. 5, The emerald-green. The pure malachite is called the sweet (schirin), and the dull the bitter (¢elch.) This is only valued very much in Syria and Europe; when it is smeared with oil, it receives additional lustre; when it is old and much worn it loses its beauty, and the white of its spots turns yellow. It appears like the turquoise bright in serene weather, and in cloudy, dull. If you rub it with natron and oil, vou obtain the purest copper. ; Sect.2. Of the Mines of the Malachite.—It is found in five places: in the mountains of Mauritania, in Kerman, in Haske- rek, near a city which was built by Efrassiab, in Turkistan, and in Arabia, in the cavern of the Beni Salem. Cuar. XVI.—Of the Lapis Lazuli (Ladschiwerd). Sect. 1. Of the Properties of the Lapis Lazuli.—tits four kinds are; namely, 1. Beduchschi. 2. Gurdschi. 3. Dermart. 4. Ker- mani. The first, i.e. that from Bedachschan, is divided mto that with gold spots, and into that without. Powdered lapis lazuli thrown into the fire- produces a many-coloured smoke. Sect.2. Of the Mines of the Lapis Lazuli.—The most remark- able of them is the lapis lazuli mountain in Chatlan, near Bedachschan, but it is also found in Georgia, in Kerman, and in other places. * Senbade is most probably the diamond spar, or corundum; and the word spar (spath) is more likely derived from senbad than from spahen, from which Adelung derives it. ‘ 1820.] “The Book of Precious Stones.” 187 Cuap. XVII.—Of the Coral (Bessed and Merdschan.)* Sect 1. Of the Properties of the Coral_—There are four kinds of corals: 1. The red. 2. The white. 3. The black. 4. The dark-coloured. They are soft and white as long as they are in the water, only become hard when out of the water, and assume different colours: the genuine can be distinguished from the counterfeit by the smell of the sea weed; in oil, they become beautiful and shining, but in vinegar soft and white. They are very much valued in China and India, because they are used for adorning the idols. Téifaschi relates that he had seen a smell- ing bottle made of a coral, a span and a half long, and three fingers broad. Sect. 2. Of the Places where they are found.—They are gene- rally fished up in the Mediterranean Sea. The best are the reddest, aud the largest of a straight stem. They are polished with spar, and bored through with steel of Damascus. Cuap. XVIII.— Of the Jasper (Jascheb, or Nassb). Sect. 1. Of the Properties of the Jasper.—\t has five kinds: 1. The white and light. 2. The whitish-yellow. 3. The black- green. 4. The transparent black.+ 5. The dust colour. In China, they make a false jasper, which is distinguished from the genuine by its smoky smell. If a vessel of genuine Jasper breaks, it is repaired with artificial pieces, which are scarcely to be distinguished from the natural. Sect. 2. Of the Mines of the Jasper.—In China there are two mines of it, of which the one called Ak Kasch produces light jasper, and the other called Kut Kasch, dark. The large pieces belong to the Emperor, the smaller to the workmen. Jasper is also found on the frontiers of Kaschgar, in Kerman, and Arabia. Cuap. XIX.—Of the Crystal (Bellor). Sect. 1. Of the Properties of the Crystal.—It is more pleasing, pure and clear than other precious stones, and is of two kinds: 1. The clear and pure. 2. The dark-yellowish. It can be melted like glass, and then coloured in imitation of the jakut, laal, or emerald. Tézfaschi relates, that in his time a merchant of Mauritania was in possession of a bath made of two pieces of crystal, which was so large that four persons could sitin it. In the Treasury of Gasnathere were four crystal vessels, each of which contained two skins (borachio) of water. Abu Rihan mentions the assertion of the lapidaries that there was often found in crystal wood, and the like, and that he himself had seen two crystals, in one of which was enclosed a green twig, and in the other a hyacinth. * Some say that bessed is the Peisian, and merdichan the Arabian word forcoralss ethers, that the former signifies the stem, and the latter the branches. ‘y The transparent black jasper may, perhaps, be the ubsidian, if it ts known to oriental naturalists. Y 188 Extracts from the Persian Work called [Maren, Sect. 2. Of the Mines of the Crystal.—The crystal is found in seven places: In India, Turkistan, Europe, Arabia, China, Armenia, and the remotest frontiers of Moghrib (Mauritania). Some prefer the Arabian to the Indian, but the least valued is. the Armenian, which is called rim-bellor. Cuar. XX.—Of the Amethyst (Dschemest). Sect. 1. Of the Properties of the Ametkyst.—The amethyst has several colours, like the rainbow, and tour kinds: 1. Deep rose- coloured and sky-blue. 2. Pale rose-coloured and deep azure. 3. Pale rose-coloured and sky-blue. 4. Deep rose-coloured and pale sky-blue. The Arabians set an extraordinary value upon the amethyst, and adorn their arms with it. Sect. 2. Of the Mines of the Amethyst.—It is found in the environs of the village of Safwa, about three days’ journey from Medina. Wine drunk out of a goblet of amethyst does not intoxicate.* CoNcLusION. Of various other Stones. Sect. 1. Of the Weschich, or Schebak (probably Jet).—It is a black stone, easily broken, which reflects objects. It is of two kinds: the Indian and the Persian; the former is better than the latter. Sect. 2. Of the Chamahen.—lIt is called the ass’s stone; it is very hard, and can only be bored by the diamond; when broke it divides into branches ; and when rubbed on a hard stone, colours it red: the most beautiful is the blackish-red; it is found in the district of Karak. Sect.3. Of Talc (Talk).—It is of two kinds: that produced in the open air, and that found in mines. Itis called sztarez semin, i.e. star of the earth, on account of its clearness and lustre. Artificial pearls are made of it, which are scarcely distinguish- able from the natural. They may be known from each other by this, that the artificial swim on the water, but the genuine sink. The tale does not burn nor calcine inthe fire. If you dissolve it and rub thelimbs with it, it makes them fire proof.+ It is found in many places; the best in Cyprus. The talc can neither be ounded in mortars, nor broken to pieces with iron hammers. he way to dissolve it is to boil it with beans, to wrap it then in * To this opinion of the amethyst, which is current also in Europe (by which it has gained the honour of being used as a test or touch stone. it seems to owe its Persian name, in which we find the name of Dschem or Dschemsshid, whose goblet is. said to have consisted of a single amethyst. The Greek name AyeSuerog is also unin toxicated, but it is originally to be derived from: Dschemest, as the jasper from Jascheb, the hyacinth from Jacut, the emerald from Semerrud, pearls (Margaritz) from Merwarid, the turquoise from Firuse, the Japis lazuli from Ladschiwerd, the sardonyx from Sard, tile from Talk, chalk from Kals, &c. &c. + If this is confirmed, it is probably the secret of the incombustibility of the Dervise Rufaji, who performed all kinds of tricks with a red-hot iron. 1820.] “ The Book of Precious Stones.” 189 a piece of linen, and to beat it till it is dissolved, and oozes like milk through the linen. If dissolved tale is mixed with a little resin and saffron, and used as ink, it makes a gold ink, and without saffron, silver ink. Sect. 4. Of the Rainstone.—A soft stone, of about the size of a large bird’s egg, which is much celebrated among the Turks, It is of three kinds: 1. The: dust coloured with red and white spots. 2. The dark-red. 3. The various coloured. Some per- sons consider it as a production of a mine ; some as an animal stone, which is said to be found in the stomachs of swine, or in the nests of some large bird. The Turkomans affirm that they an produce rain and snow with this stone. ° Sect. 5. Of the Lagle Stone —Ilf you shake it you hear it rattle as if there were something in it; and on breaking it, you find nothing in it. Sect. 6. The Jarakan (the’ Jaundice Stone).—It is a stone with red and yellow spots, which, when it is rubbed, leaves a red mark. It is so hard that it can only be bored through with the diamond ; a little black stone which the swallows carry into their nest to cure their young of the jaundice. Sect. 7. The Vinegar Sione.—It attracts vinegar, but cannot remain in it, as it always flies out when thrown into it. Sect.8. The Oil Stone is set in flames when water is poured over it, but it is extinguished with oil. Sect. 9. The Jew’s Stone.—A shining stone, which is produced in the sea, and has three kinds: 1. The round. 2. That in the shape of a nut. 3. The oval ; is often marked with black stripes, is hurtful to the stomach, but very useful to the bladder. , Sect. 10. The Milk Stone, which, when rubbed, leaves a white mark ; it is ash-coloured, and has a sweet taste. Sect. 11. The Mouse Stone, which has the smell of mice. Sect. 12. The Blood Stone, also Schadendsch, i.e. Lentil Stone, —This last kind is used to polish the surface of the eye (den spiegel des auges damit zu glatten). ; Sect. 13. The Moon Stone, a stone with spots, which become Jarger and smaller with the increase end wane of the moon. Sect. 14. The Colour Stone, which always reflects different ‘colours. Sect. 15. The Sleep Stone, which produces sleep when hung over the bed. Sect. 16. The Stone Miskal, which is said to be thrown up from the Mauritanian Sea. Sect. 17. The Marcasite, likewise called the Stone of Bright- ness, is divided into several kinds : the gold marcasite is dug up near Ispahan, and is called Ebrendsche ; it is used to polish the spinellus: the silver marcasite comes from the frontiers of Bedachschan ; the copper and iron marcasite is similar to copper and iron. Sect. 18. The Magnina (Manganese?) which is used by the glass manufacturer, It is divided into that with little and inte 190 Dr. Prout’s Description of an Apparatus for [Marcn, that with large shining spots; but according to the colour into the blackish, yellowish, and reddish. Sect.19. Of the Stirme and Tutia (query Antimony ?).—it is a bright, heavy, transparent, black stone, which is divided accord- img to the country where the mines are situated, into those o. Ispahan, Herat, Sabulistan, Georgia, and Kerman. The first is the best, the last the worst ; if powdered Stirme is applied to the eyes, it increases their polish. The tutia (the genuine eye-paint), is divided into those of Kerman, Kand, India; the last is pure and white like salt; that of Kerman yellowish. It is made by Jaying the natural tutia stone upon coals, and catching the vapour in an alembick upon nails. The lightest tutia, and the best for the eyes, is that which forms on the points of the nails, the second sort on the middle, and the coarsest sort on the heads of the nails. The Indian is produced on the shore of the sea, and is much used in alchemy. ~ Sect. 20. Of the Proportions of some precious Stones to others. —Abu Rihan is said to have found by experiment that a miskal of blue jakut is equal in size to five dank * and three tissu of red jakut, or to five dank and two and a half ¢zssw of laal; and that four dank minus a ¢zssu of coral are equal in size to four dank minus two tissu of onyx and crystal. The mode of discovering the size and weight is the followmg: a vessel is filled with water, and the stones thrown singly into the water; the quantity of water which is expelled from the vessel by means of each stone is equal to the room it occupies. God knows best. ARTICLE VI. Description of an Apparatus for the Analysis of organized Substances. By W. Prout, M.D. F.R.S. &c. TueEreE is nothing new in the principle upon which the analy- tical process is conducted by the following apparatus. The sub- stance to be analyzed is introduced into a glass tube, G (PI. CII), (about 1th or 4th of an inch in diameter, and 10 inches long) mixed with the requisite quantity of the black oxide of copper, precisely in the same manner and with the same object explained by me ina former paper on this subject.* The tube above-men- tioned is inserted firmly into a piece of cork at its upper and open end in such a manner that about half an inch of it may project beyond the larger end of the cork. The cork is then placed in the conical hole in the piece of brass, C (fig. 2), fixed in the ® According to Meniuski, a dank is equal in Egypt to three carats ; according to Cassira, two in Spain. It is the fourth part of a drachm, but according to Ver- heng the sixth. The dissu, according to Ferheng, weighs sometimes two, sometimes four barley corns; and the miskal is one drachm anda half,. + See Med. Chirurg. Trans, vol. viii. p. 526. Page 1 IO 14 | = —_- i e | Engraved tor D° Thomson's Annals — tor Baldwin Cradock & . hiy, Lilernoster Row, March 21820. 1820.) the Analysis of organized Substances. 191 bottom of the wooden dish, H, and the dish is placed upon the support, D, which has a hole in its centre adapted for receiving it. F, is a spirit lamp with a circular wick, like the common Argand lamp. This lamp stands upon a support, C (fig. 1), capable of being moved up and down by means of the counter- poize weights, M M, attached to the lines passing over the pulleys, LL, in a manner easily understood by a bare inspection of the figure. The tube, G, passes through the centre of the lamp, and thus is enveloped equally on all sides by the flame. The gaseous products are collected in the graduated tube, K, which had been previously filled with mercury, and inverted im the wooden dish above described likewise partly filled with mercury. The external glass tube, I, is furnished with a brass screw cap by which it can be attached at pleasure to the piece of brass fixed in the bottom of the wooden dish, in the manner shown in fig. 2. The use of this tube is to afford an easy means of equalizing the height of the mercury on the inside and outside of the tube, K, and thus to supersede the necessity of calculation. N is a cir- cular tin plate, with a hole in the centre, of such a size as to admit the tube, G. This plate is suspended by wires from the support, D; and its use is to prevent the action of the flame of the lamp upon the wooden dish, H, and its contents. Fig. 3 is a small mercurial gasometer, which may be used instead of the dish and graduated tube when it's desired to take the specific gravity of the gaseous products. “The tube, G, in this case is fixed into the brass cap, e, by means of a cork. When the above apparatus is employed, the lamp, F, is raised to the upper part of the tube, G (two or three inches of which at this part is filled with pure oxide of copper only), and there permitted to stay till the tube becomes red-hot. When this is the case, it is depressed a little, and another portion of the tube similarly heated, and so on, till the whole of the tube has been heated in succession, when the operation is completed. The gaseous pro- ducts are then analyzed in the usual manner, if the substance submitted to the operation has contained azote; if not, the oe of the gas (except a very minute quantity) will be carbonic acid. The proportion of hydrogen in a substance may be ascertained im several different ways by means of this apparatus. A mode I have commonly practised is (after filling it as usual) to exactly counterpoise the tube, G, in a delicate balance, and when the process is finished to see how much it has lost in weight by the operation. The quantity of gases produced by the same substance being previously known, the quantity of hydrogen may be thus readily estimated. Another mode is to actually collect ‘the water formed, and to weigh it. This may be effected by having the tube in the shape represented in fig. 4. At the end of the operation, most of the water will be found collected in the part O, and to ensure the collection of the rest, another tube filled with dry muriate of lime may be attached to the end, P. Another ‘192 Analyses of Books, ° [Marcu, mode is that recommended by Mr. Porrett. The quantity of gases being ascertained as usual, the oxide of copper employed in the experiment is to be put into sulphuric acid. The portion of the oxide which has been reduced is thus obtained in a metallic state, and consequently the quantity of oxygen which has been expended may be thus ascertained. Of these methods, the first appears the most simple and least liable to error. The above apparatus is susceptible of far greater precision, and is much less troublesome to use than any that has hitherto been recommended for the analysis of organized substances. There may be cases in which its use is inapplicable, but these I am persuaded are few.* In conclusion I may observe that I have for several years been engaged in the analysis of organized products, and have at length extended my researches to almost every distinct and well defined substance. The results, when compared with one another, are most interesting, and seem to throw no small light not only on the nature of chemical compounds in general, but upon many important points connected with animal and vegetable physiology and pathology. Anricie VII. ANALYSES OF Books. Memoirs of the Literary and Philosophical Society of Manchester, Second Series. Vol. III, 1819. (Concluded from p. 141.) VI. On the refractive Powers of Muriatic Acid and Water. By Mr. Henry Creighton.—The author, during a course of expe- riments on the application of different fluids to the formation of compound lenses, with a view to correct aberration, was led from Dr. Blair’s observations to notice particularly the effects of muriatic acid. He was surprised to find that when such a com- pound lens was used, the focal distances were proportional to the specific gravity of the muriatic acid employed. The following table exhibits the focal distances with acid of different strengths. The first column exhibits the specific gravity of the acid employed, the second column the focal distances, and the third column the specific gravity calculated from the supposition that it is proportional to the focal distance. The focal distances of the two double convex lenses were about 24 and 27 inches respectively ; when placed together in the frame about 13; * The annexed sketch represents the apparatus just as it was origiually con- atructed.. Perhaps it might be improved by having, isstead of the dish, H, am oblong vessel furnished at one end with a deep well for equalizing the height of the mercury on beth sides of the graduated tube, K, in which case the external tube, I, as well as the gasometer, fig. 3, would be unnecessary, 1820.] Memoirs of the Literary Society of Manchester. 193 y 'y of when the space between them was filled with water, nearly 24; ‘and when muriatic acid of the specific gravity 1-177 was mtro- duced, the focal distance was 28 inches. Sp. gr. of Sp gr. deduc- Liquids. ditto by ex- oe ed from focal periment. "distances. : Inches. RR ere oS eel at mst 7000 23°75 1-000 Ditto with alittle acid. ...... 1-055 25°00 1-053 Ditto with more acid.........} 1:087 25°70 1-088 Pemy ILL, CIELO... o's he len.e hg 26°60 1°12] REO CMS UIELG 5 at: s eo he can 1-146 27-00 1-138 MPIC ENO Ns 5 sain osese ae ee > Pare 28°00 1-180 The lenses. in these experiments were made of crown glass. The experiments were repeated with lenses of flint glass and crown glass ; but the results were the same. On trying the same experiments with nitric and sulphuric acid, he found that the specific gravities increased at a muc!i greater rate than the focal distance. From this remarkable property of muriatic acid, the author suggests the use of such a compound lense to deter- mine the specific gravity of the acid. VIL. An Essay on the Origin of Alphabetical Characters. By the Rev. William Turner, Jun. A.M.—It has been pretty gene- rally maintained by literary men that the first alphabet was made known to mankind by Divine revelation. Dr. Hartley was of opinion that it was revealed from Mount Sinai when the ten commandments were written by the finger of God on two tables of stone. The same notion was supported by the celebrated Gilbert Wakefield in an ingenious paper on this subject inserted in the second volume of the Memoirs of the Manchester Society. Mr. Turner’s object in the present essay is to combat this opinion, and to show that letters, like many other discoveries, not inferior in difficulty and importance, may have been the fruit of human sagacity properly directed. The essay is divided into two parts : in the first, he endeavours to answer the arguments advanced by Mr. Wakefield in support of the Divine origin of letters ; in the second, he gives his ideas of the way in which the discovery ‘may have been made. Mr. Wakefield’s first argument is, that the invention of letters differs in one remarkable particular from all others; namely, that the first effort brought it to perfection. This assertion Mr. Turner is disposed to deny. We have no evidence that it was perfected at once. The first rude attempts would be forgotten im consequence of the more perfect ones that followed them. Even the Hebrew alphabet seems at first to have been very rude. If the Phoenicians borrowed their written language from the Vou. XV. N° III. N 194 Analyses of Books. |M ARCH, ‘Hebrew, the Hebrew alphabet must have consisted at first of only 16 letters. Mr. Wakefield’s second argument is, that if alphabetical writ- ing was the result of human ingenuity, we might reasonably have expected to hear of the vention having been made in more places than one ; but this is not the case. All the alphabets at present in existence may be traced either by external or mtermal evidence to the same source. This Mr. Turner admits. Al! the European alphabets (the Russian excepted, who got it imme- diately from the Greek) may be traced to the Roman. The Roman was derived from the Grecian, and the Grecian from the Phenician. The Coptic, Ethiopic, and Arabic alphabets are referable to the same quarter. But that this fact, though curious and remarkable, furnishes proof of the Divine origin of letters Mr. Turner denies; because the same thing may be said of several other arts which yet have never been alledged to be of Divine origin. For example, the nine digits. All Europe derived them from Spain. The Spaniards. got them from the Moors, the Moors from the Arabians, and the Arabians from the East Indies—a region in which many of the arts and sciences flourished in a very remote period of antiquity. Mr. Wakefield’s third argument is, the uniform failure of all those nations who have continued for a great length of time unconnected with the rest of the world in their attempts to devise any contrivance similar to the alphabetical characters, or at all comparable to them in simplicity and convenience; though they have made considerable proficiency in various other arts and sciences. But Mr. Turner replies that the failure of the Chinese in inventing an alphabet is no more surprising than that such acute people and such mathematicians as the Greeks should have failed in contriving numeral characters comparable to the Arabic in simplicity and utility. Mr. Waketield’s fourth argument is, that the transition from hieroglyphics to letters, which has been commonly supposed, is by no means an easy or obvious thing. This Mr. Turner admits, but denies that it is any argument in favour of the Divine origin of letters. Though they were not derived from hieroglyphics, they may have been invented in another way. In the subsequent part of this paper, the author states his objections to Mr. Wakefield’s opinion, and endeavours to give an idea how the discovery of letters might have been made. His objections are: 1. The want of necessity for such a sup- position. 2. The total want of historical information on the subject, which could hardly have been the case had letters been . derived from the immediate revelation of God. Dr. Hartley’s . notion that they were first communicated by God in the ten : commandments cannot be true, because writing is spoken of before the delivery of these commandments (Exodus, xvi. 14), | 1820.] Memoirs of the Literary Society of Manchester. 195 and because the ten commandments do not contain all the letters in the Hebrew alphabet. Our author supposes that when men set about devising methods of committing language to writing, two modes would suggest themselves: 1. To suggest to the eye by visible signs the ideas expressed by spoken language. This would introduce hieroglyphics, from which the characters of the Chinese would be naturally derived. 2. To devise a system of visible signs corresponding to the words used in spoken language. These marks would be gradually systematized; similar sounds would be denoted by similar marks. When these marks nuultiplied, the idea of ascertaining the number of sounds in the language, and applying a mark for each, would naturally suggest itsell, and the transition from this to letters was comparatively easy. Vil. Observarions on the Rise and Progress of ike Cotton Trade in Great Briiain, particularly in Lancashire and. the adjoiming Counties. By John Kennedy, Esq.—This interesting paper contains no information about the introduction of the cotton trade into Lancashire. We know from acts of parliament that it existed there during the reign of Queen Anne, though probably to a very limited extent. From a note added to the paper, we learn that Mr. John Wyatt, of Birminghain, inveated a spinning machine in the year 1733, in a small building near Sutton Coldfield. He afterwards joined with Lewis Paul; but the project turned out unfortunately. Paul contrived to get a patent taken out in his own name m 1738 for some additional apparatus. In 1741 a mill turned by two asses walking round aa axis was erected in Birmingham, and 10 girls were employed in attending the work. But this establishment was unsuccessful, and the machinery was sold in 1743. A woik ona larger scale on a stream of water was established at Northampton under the direction of Mr. Yeoman, but at the expense of Mr, Cave. It contained 250 spindles, and employed oU pair of hands. But. this new establishment was also unsuccessful ;, and as no model of Mr. Wyatt’s machine remains, its nature and principles are at, present unknown. - The operation of weaving still remains nearly the sane as. it did a century ago, with the exception of the fly shuttle, which Was invented in 1750 by Mr. John Kay, of Bury. At that time the cotton was carded and spun in the weaver’s family, and the manufactory was carried on to an extent sufficient to supply_a limited home consumption. The occasional fluctuations in the demand from bad seasons, searcity of food, &c. led the manu, facturer to endeavour to find a market for his goods in other countries. This gave rise to the foreign trade with all its advans tages and disadvantages. The demand increased beyond the ability of the manufacturer to supply. This occasioned. an incessant demand for new hands, and led to the contrivance of every expedient to make the work done by their labourers as N 2 196 Analyses of Books. (Marcu, great as possible. A division of the labour was first thought of {Instead of carding, and spinning, and weaving, in the same house, one family’s sole employment became carding, another’s spinning, and that of a third weaving. The attention of each being thus occupied by fewer objects, he was able to perform a greater quantity of work than before. Gradual improvements in the mode of carding and spinning oce..sionally suggested them- selves till at last they arrived at a machine, which, though rude and ill constructed, enabled them to produce more in their respective families. By degrees, the cottages became filled with their little improvements till they were in some measure forced out of their dwellings by the multiplication of their implements. Thus carding and spinning became two distinct professions. First, a boy or a girl was enabled by means of two pair of stock- cards to do more work than before. A cylinder revolving on its axis was next introduced, and carding was performed by holding four or five pairs of stock-cards against it. This was the rude beginning of the carding machine, and in this state it existed about 60 years ago. This, about 10 years after, was followed by another machine, called the spinning Jenny, invented in 1767 by Mr. Hargreaves, of Blackburn, by means of which a young person could work 10 or 20 spindles at once. This machine was at first turned by the hand; but horses: were soon substituted for human labourers ; and when the size of the machines came to be such as to render the application of horses expensive and troublesome, falls of water were sought out and resorted to. It was at this time that the admirable inventions of Mr. Ark- wright were introduced into the cotton trade. The comforts and independence of the workmen had gradually improved, and with them the nature of their mechanical inventions. They were enabled to employ smiths, carpenters, and millwrights to realize their ideas, and by their superior skill they were enabled to make their machinery much better suited to the objects intended than their own original and imperfect fabrics. The inventions of Arkwright were of a higher kind ; and to realize them, the assistance of a still higher class of mechanics, watch and clock- makers, whitesmiths, and mathematical instrument makers, were called in and employed. Mr. Arkwright’s first mill was built at Cromford in 1771, and for a period of 10 or 15 years after, all the principal works were erected on the falls of considerable rivers, no other power but water having been then found to be ractically useful. It was not till about the year 1790 that Mr. Watt's steam-engine began to be understood, and introduced in the neighbourhocd of Manchester. In consequence of the introduction of this admirable machine, water-falls became of less value, and instead of carrying the people to the power, it was found preferable to place the power among the people wherever it was most wanted. This led those who were inter 1820.] Memoirs of the Literary Society of Manchester. 197 ested in the trade to make many and great improvements in their machines and apparatus for bleaching, dyeing, and print- ing, as well as for spinning. Had it not been for this new accession of power and scientific mechanism, the cotton trade _ would have been stunted in its growth, and, compared with its present state, must have become an object only of minor import- ance in a national point of view. ‘The effects of this engine have been nearly the same in the iron, woollen, and flax trades. In the year 178 new and valuable machine appeared, called at that time the hall-in-the-wood machine, from the name of the ylace where the inventor, Mr. Samuel Crompton, lived, near olton, in Lancashire. It is now called the mule, from its uniting the principles of Mr. Hargreave’s jenny, and Mr. Ark- wrighi’s water frame. This machine, by producing at a small expense, much finer and softer yarn than any that had been seen before, gave birth to a new and most extensive trade. Before the year 1790 the mules were turned by hand, and were con- fined chiefly to the garrets of cottages. About that time Mr. Kelley, of Lanark, first turned them by machinery. The application of the steam-engine to this purpose produced another great change in this branch of the trade. The mules were removed from cottages to factories, were constructed more substantially and upon better principles, and produced yarn of a more uniform quality and at less expense. In 1797 a new machine for cleaning cotton was constructed by Mr. Snodgrass, and first used at Johnston, near Paisley, by Messrs. Houston and Co. This was called a scutching or blowing machine. [t was first brought to a siate of perfection by Mr. Danlop, of Glasgow. It was not introduced into the neighbourhood of Manchester till 1808. It is now generally employed, and is said to have been greatly improved by Mr. Arkwright and Messrs. Strutts. What are called power looms were first constructed by Dr. Cartwright, at Doncaster, in 1774. But though they made good cloth, in consequence of the great loss of time in dressing the warp, they possessed no important advantage over common looms. in 1803 Mr. Thomas Johnson, of Bradbury, Cheshire, invented a beautifal and excellent machine for warping and dressing warps preparatory to weaving, by which the operation is performed much better and cheaper than it can possibly be dove by hand. This is a great advantage to the power loom, and in consequence some large manufactories of the kind have been established first in Scotland, and afterwards in England. But as one person cannot attend upon more than two power looms, it is still a doubtful question whether this saving of labour counterbalances the expense of power avd machinery, and the disadvantage of being obliged to keep an establishment of a looms constantly at work ; while in the common way the oms sight be stopped or turned to a different kind of weaving, 198 Analyses of Books. [Marenu, ifthe demand for the particular kind of goods they were weaving should change or fall off. Such is a sketch of the historical facts contained im this inte- resting paper. 1 regret that I cannot touch upon the observa- tions which it contains respecting the alterations in the morals, the habits, and the feelings of the common workmen produced by, or accompanying these, improvements. They deserve the articular attention of statesmen and political economists. Wiitess means can be fallen upon to prevent that degeneracy which has hitherto been the Jot of all the manufacturing popu- lation in every country, it is obvious that all manufacturing countries must sooner or later work their own destruction. The following is the quantity of raw cotton consumed or converted into yarn in Great Biitain and ireland during 1817: Peni imparted’: fe 5o 2.5 cleat hha Veet Bata 110,000,000 lbs, Loss in spinning (14 oz. per Ib.) ..... VAgt(: Mt 10,312,500 Ibs. Marn+produced, so). 6.56%. 4 Silat ingakatt cea a 99,687,500 lbs. Number of hanks (at 40 per Ib.) ............ 3,987,500,000 Number of spindles employed (each producing two hanks per day, and 300 working days in PEATE “WSK ee ods s sinabe eects hte Oe oh oR 6,645,833 Number of persons employed (supposing each to produce 120 hanks per day)....... ’ 110,763 Number of horses power employed (supposing 4+ oz. coal to produce one hank of the 4U and 180 Ibs. coal per day = one horse power) 20,768 _ IX. Memoirs on a new System of Cog and Toothed Wheels. By Mr. James White, Engineer.— Mathematicians have demon- strated that the form of the teeth of wheels, in order to move equably and without fricuon, should be regulated by the curve ealled the epicycloid. But this holds only when the pins of the pinions which they put in motion are indefinitely small, whieh never can hold in practice. This circumstance has prevented workmen from attempting to make the figure of the teeth of their wheels correspond with the theoretical figure. The object of the present paper is to make known a method of cutting the teeth ot wheels so as that they shall give smooth and equable motion, and as little friction as possible. For. this method, 'a patent was taken out some vears ago by the author of the paper. X. On the bleribility of all Mineral Substances, and the Cause of Creeps and Seats in old Coal Mines. By Mr. John B. Long- mire.—The author has observed a very great flexibility in sand- stone and slate clay in excavated coal mines. He has likewise seen certain varieties of limestone and clay-slate bend consider- ably when in the act of being separated into small parts 7 wedges and other tools. From these facts, he infers that all 1820.] Memoirs of the Literary Society,of Manchester. 199 kinds of mineral matter, however hard and brittle they appear to be in hand specimens, will bend less or more when formed into large flat pieces. He explains what are called creeps in old coal mines. This name is given to the slow subsidence of roofs of old coal mines. When the roof sinks rapidly, the process is called a set or seat by the colliers. X{. Account of the Black Lead Mine in Borrowdale, Cumber- land. By Mr. Jonathan Otley.—This mine, according to Mr. Otley, lies in a greywacke mountain near the head of the valley of Borrowdale, which faces the south-east. The black lead does, not constitute a vein, but occurs in bellies. Veins of iron ore traverse the mountain, exhibiting traces of black lead, and it is where these veins cross each other that the bellies usually occur. When the mine was discovered is not known; but from a grant made in the beginning of the 17th century, it appears to have been discovered before that time The manor of Borrow- dale is said to have belonged to the Abbey of Furness, and having, at the dissolution of that monastery, in the reign of Henry VIII. fallen to the crown, it was by James I. granted to William Whitmore and Jonas Verdon, including among other things, the Wadholes and Wad, commonty called Black Cawke, of the yearly Rent or Value of Fifteen Shillings and Fourpence. The said William Whitmore and Jonas Verdon, by a deed bearing date Nov. 28, 1614, sold unto Sir Wilfred Lawson of Isel, and several inhabitants of Borrowdale, all the said manor of Borrow- dale, with the appurtenances of what nature or kind soever ; “‘ except the wadholes and wad, commonly called black cawke, within the conimons of Seatollor, or elsewhere, within the commons and wastes of the said manor.” In consequence of this reservation, the black lead mine is held distinct from other royalties of the manor; one half thereof belonging to Henry Banks, Esq. M.P. and the other half subdivided into several shares, one of which belongs to Sir Joseph Banks. The mine used formerly to be wrought at irregular intervals, and when the market was supplied, the working was stopped tilla fresh demand called for a new supply of black lead. But. of late years the demand has increased so much that it has been neces- sary to work the mine without intermission. In the year 1798 an adit was begun on the side of the hill, which at the length of 220 yards communicated with the bottom of the old workings. Through this level the water passes off, and the produce is. brought out to be dressed: and on its mouth a house is built where the overseer dwells, and the workmen are undressed and examined as they pass to and from work. From a belly opened in 1803, 500 casks of black lead of the best quality were pro- cured, weighing about one hundred weight and a quarter each; besides a greater quantity of an inferior sort, Since that time two of these bellies have been met with, which have produced’ about 100 casks. each. The whole is sent to London, where it 200 Analyses of Books. [Marcn, is exposed to sale in the Company’s warehouse on the first Monday of every month. The great consumption is in the manufactory of black lead pencils. Many of these are made at Keswick ; but the makers are obliged to bring all the black lead from London. Great improvements have been introduced into the manufactcry of these pencils. A method of hardening the black lead has been’ discovered. This, according to Mr. Otley, consists in eng the black lead into slices about ,,th of an inch in thickness, an then keeping it for some time in melted sulphur. Xif. Account of a White Sclar Rainbow. By the Rev. R. Smethurst.—This rainbow was observed on Noy. 28, 1816, about two, p.m. There was a considerable fog on the sarface of the earth, which was clearing away in the higher regions of the atmosphere. There were no visible drops of rain. The sun was visible through the fog; but its rays were not sufliciently powerful to occasion shadows of objects. The whole rainbow was very well defined, except a small portion at the centre. The distance seemed 100 yards, and the span of the arch about 120 yards. Its breadth was about twice that of an ordinary rainbow; its colour grey; near the ground the colour was brighter than towards the centre. In each leg, about an equal distance from each edge, was a streak of white, reaching apparently to the height of 16 or 18 yards, of peculiar brightness. XIII. Remarks (chiefly agricultural) made during a short Excursion in Westmoreland and Cumberland, in August, 1815. By John Moore, Jun. Esq.—This is a very amusing and interest- ing account of the cbjects which struck the attention of the author during an excursion to the lakes. It will repay the perusal of the agricultural reader. But from the nature of the details, they are scarcely susceptible of abridgment. From Bolton to Blackburn the soil seems to be poor, and the farming bad. The author thinks that too much of the soil has been” ploughed up, and informs us that it is difficult to recover the grass after 1t has been once destroyed. He considers the planting of whole potatoes a bad practice ; and thinks that in 30 years the growth of the oak overtakes that of the larch. Hence, in his opinion, oak is a more profitable tree for planting than larch. He was surprised to observe promising crops of oats and barle growing upon Latrig, at-a height, according to Mr. Otley, of 1100 feet above the level of the sea; but he doubts how far the spirited experiment will remunerate the farmer. He recommends bringing the seed corn rather from a colder than a warmer climate ; because it ripens much sooner. The wheat straw near Lancaster was of the same beautiful colour as on the chalk lands of Bedfordshire. But it does not appear that this straw is put to’ the same use as at Dunstable, where it is not unusual for a crop of wheat straw to sell for more than the grain. XIV. A Tribute to the Memory of the ‘late President of the a ~ 1820.] Memoirs of the Literary Society of Manchester. 201 Literary and Philosophical Society of Manchester. By William Henry, M.D. F.R.S. &c.—This paper has been already published in the Anna/s of Philosophy, vol. xiv. p. 161. XV. An Essay on the Signs of Ideas, or the Means of convey- ing to others a Knowledge of our Ideas. By Edward Carbutt, M.D. Physician to the Manchester Infirmary, &c. &c.—By idee the author of this paper means the remembrance of a sensation. He is of opinion that the sensations of the eye and ear may be remembered, but is doubtful whether this be the case with those of the nose, the mouth, or the feeling. A remembered sensation or idea is always fainter than the sensation itself, except in cases of insanity. Words are usually considered as the signs of ideas. But our author is of opinion that we very seldom succeed in conveying our own ideas into the minds of our hearers or readers. It is impossible for us to have a name proper for each individual idea or set ofideas. On this account, names have been generalized ; and when the appellations tree, horse, man, had been given to one individual of each of these kinds, they naturally enough came to signify any individual of that kind. Hence the originak of general terms, which, by a strange perversion, have been stated to stand for general ideas; whereas a general idea can- not possibly have any existence; all ideas are and must be particular. The author conceives that there are four sets of words which in no wise represent ideas. 1. Words which, from the nature of things, are altogether devoid of archetypes. Thus the mathematical terms point and fine, our author thinks cannot possibly convey an idea to the mind. This mode of speaking depends upon our author’s defi- nition of ?dea, which restricts its meaning more than is usual in the English language. A point, in the mathematical sense of the word, is the place where one line terminates and another begins. Of this I have an accurate notion. But whether it be the remembrance cf a sensation will admit of some dispute. The same remark applies to the mathematical word dine, which means the place where one surface terminates and another begins. 2. Words standing not for ideas; but either for simple and original sensations as are never ideally renewed, or for sensa- tions of emotion, which are never called up, except by the original cause, and cannot, therefore, in any case be calied ideas. When we reason concerning such sensations, we merely employ the words, which are the names of the original sensations ; and from these words the author thinks that we can reason just as correctly as from real ideas. I must acknowledge that I do not see the full force of this distinction. It appears to me to be rather fanciful than real. Any person who has been accustomed to smell a rose will immediately recognise the same smell when 202 Analyses of Books. [Maren, a bottle of otto of roses is held to his nose. How could this be the case if he did not remember the smell of a rose; that is, if he had not an idea of the smell of a rose, according to our author’s definition of idea. In the same way we can remember tastes and feelings, and even particular kinds of painful or leasant feelings, and recognise them again whenever they occur. his shows clearly that our author’s distinction is fanciful. 3. Words standing for causes whose effects alone we witness, and thence judge the existence of the cause, without being able to form any conception of it. The terms Aeat and co/d, when used for material agents, our author considers as of this kind. I do not perceive the accuracy of this opinion any more than of the preceding. 1 have just as good a notion of heat as a cause as 1 have of any other cause whatever. With respect to the Supreme Being, it is true that we can form no precise notion of his shape or size ; but we can form pretty exact ones of his power, his wisdom, his goodness, &c. 4. Words which at present have no ideas attached to them, although the contrary might have been the case when they were originally brought into use. In consequence of the existence of such words, our author thinks that a man cannot understand English without the knowledge of all the languages from which it.is derived. Now I must acknowledge that (laying unmeaning oaths aside, which are now banished polite conversation) 1 da not believe that any such words occur in the English language. Our author gives b/asphemy, as an example, and heresy as another. Now the meaning of the word blasphemy in the New Testament is an attempt to lower the character of God, knowing” the allegation to be false. Now this is the meaning which it bears also in the English language. Heresy now signifies reli- gious opinions contrary to those established by. law. It is Ekewise the term which a man (supposing no religion established, by law) would apply to every set of religious doctrines contrary to-his own. In this way might every English word be defined, and. a mere Englishman, if he were to make himself acquainted with these definitions, would understand his own language better than the most learned etymologist in the universe. Would an Englishman understand the meaning of the word physiciam any better by being told that it was derived from a Greek word which signifies a naturalist ? XVI. Account of some remarkable Facts observed in the Deoxi= dation of Metals, particularly Silver and Copper. By Samuel Lucas, Esq.—According to Mr. Lucas, when silver or copper 18 kept melted in contact with the air, the metal absorbs a portion of oxygen, which it retains while in fusion; but on the metal. becoming solid, the gas is extricated with considerable rapidity,, and occasions an explosion if the extrication takes place by, pouring the melted metal-into water. The gas extricated from silver m this way was examined by Mr. Dalton, and found to, ‘ 1820.] Memoirs of the Literary Society of Manchester. 203 contain 87 per cent. of oxygen gas. The impurity was probably owing to an accidental mixture of atmospheric air. Though it is difficult at present to give any explanation of this singular phenomenon, is it not possible that it may Le somehow con- nected with the extrication of oxygen gas when silver is placed im contact with deutoxide of hydrogen ! When the silver or copper is covered with charcoal, and then thrown in fusion into water, no gas is extricated from it. XVIL. Udservations on the Callous Tumour. By Mr. Kinder Wood.—This is a name given to a tum*ur which surrounds the fractured part of a bone, when it is uniting together, and: which continues till the adhesion is complete, or till a perfectly bony cement has perfectly united the two fractured portions of bone. Mr. Wood’s observations were deduced from fractures made on the limbs of young rabbits. These were allowed to remain with- out any attempt to replace the bones, and the progress was ascertained by dissection at various distances of time after the fracture. The fracture occasions a loss of vital energy, and about 12 hours elapse before any visible attempt at repairing the injury commences. The ends of the fractured bones are at first rough, which occasions them to injure the muscles in their neighbour- hood. The first change that takes place is the effusion of a quantity of coagulable lymph from the internal membrane of the bone. By this, the fractured faces are covered, and made beau- tifully smooth. This lymph adheres firmly to the internal periosteum, and obviously proceeds from it. About 36 hours after the fracture most of the extravasated blood is absorbed. The external membrane of the bone becomes thickened. and vascular, a quantity of coagulable lymph exudes from this membrane and from the muscles, and surrounds and envelopes the ends of the fractured bone. It is this exudation which constitutes the callous tumour. It becomes gradually firmer and firmer, the external periosteum of the bone below it is destroyed and removed, and a new periosteum formed which encloses the callous tumour, and fixes it firmly to the bone. The earthy salts are slowly deposited in this tumour, and in proportion as the bone acquires strength, the tumour is dimi- nished ; but along time elapses before it disappears. When the external periosteum of the bone is destroyed, no callous tumour is formed, the ends: of; the bone lose their vitality, and must be removed before the fracture can be healed. When the internal periosteum is injured or destroyed while the outer remains, the callous is formed as usual ; but the bones do not unite, because their asperities are not removed by the usual deposition of coagulable lymph. The consequence: is, that the callous gradually assumes the form of a capsular ligament, the inner periosteum gives out a glairy fluid resembling synovia, and an artificial joint is formed. 204 Analyses of Books. (Marca, XVIII. On the Possibility of reconciling the scriptural and profane Accounts of the Assyrian Monarchy. By the Rey. John Kenrick, A.M.—From the Old Testament, it appears that the monarchies which existed in that part of Asia, which was after- wards the seat of the Assyrian monarchy, were originally very small; for a king of Shinar, confederated with a hing of Elam -and twu others, came and attacked some petty sovereigns of Palestine; and Abraham, arming his own household, was able to defeat the invaders. David had a war with the King of Tobah, which was at so short a distance from Nineveh, that had that city been the seat of a great monarchy, Tobah could not possibly have been independent, nor could David have attacked it without coming into hostilities with the sovereign of Nineveh. The first mention of conquering monarchs at Nineveh in the Jewish annals is in the reign of Pul, 771 years before the Chris- tian era, by whom and his successors, Syria and Palestine were invaded, and the two branches of the Jewish people reduced to dependence and captivity (2 Kings, xv. 19). Such is the anti- quity and uninterrupted series of the Jewish annals, and such the position of the Jewish nation relatively to a power on the banks of the Tigris, extending its dominion westward, that we may safely say that had any such power existed previously to the eighth century before Christ, it must have come into collision with the Jewish nation, and that collision would have been -recorded in Jewish history. From Herodotus (whose Assyrian history is lost) we learn little more than that the Assyrians had been masters of Upper Asia (Asia beyond the Halys) 52U yeais, when the Medes shook off the yoke; which (reckoning backwards from 710 years before Christ) brings us to 1250 years before Christ. But this account, though improbable, is not inconsistent with the scrip- tural history; since the Assyrians might be masters of Upper Asia without holding the sea coast. It is from Diodorus Siculus that the usual account of the early Assyrian monarchs is obtained. Ctesias is his authority. He was a Greek, and posterior to Herodotus, and even by many of the ancients his history is looked upon as fabulous. According to him, Ninus, a prince of boundless ambition, engaged the Arabians under his standard, subdued Babylonia, Armenia, and Media, and proceeded thence to remoter countries of Asia, which he reduced, with the exception of Bactria and India. ‘Thence, turning his arms towards ihe west, he overran all the countries from the Euphrates to the Mediterranean, and from the banks of the Tanais to the cataracts of the Nile. After these exploits, he builds Nineveh, which he names from him- self. He then returned to his former unsuccessful attempt on Bactria, and deprived Menon, the chief officer of his army, of his wife, Semiramis, making her his own queen. Semiramis succeeded Ninus. She founded Babylon, aad spent the rest of 1820.] Memoirs of the Literary Society of Manchester. 205° her days in warlike expeditions and public works. After an unsuccessful expedition into India, she died miraculously, leav- ing the kingdom to her son Ninyas, who began a course of effe- minate sloth and luxury, which his successors followed for 30 generations, without leaving a single fact for history, till the time of Sardanapalus, whose vices roused the indignation of Belesys, the Babylonian, and Arbaces, the Mede. They rebelled, besieged him in Nineveh, and drove him to the desperate expe- dient of burning himself, his haram, and his treasures, to avoid falling into their hands. With him ended the Assyrian monarchy, according to Ctesias. It is needless to observe that this account of Ctesias is utterly irreconcilable with the Old Testament history. It is equall devoid of probability. A series of 30 generations of kings sunk in absolute indolence, allowed to reign without molestation, is utterly incredible. Our author is of opinion that Ninus, Semi- ramis, and Sardanapalus, were the names of the Assyrian deities, and that the fiction originated from a practice common with the ancients of assigning the origin of nations to gods, and contriving a set of actions suitable to their conceptions of these divine kings. This opinion he supports with much ingenuity, and a great deal of learning ; and his solution of the difficulty is fully as plausible as any hitherto proposed. But I cannot see any reason for putting any confidence in the account of a writer who lived so long after the events which he attempts to describe as Ctesias, unless he had favoured us with the contemporary authorities upon which his supposed facts were founded. Now this, in the present circumstances of the case, would have been obviously impossible. XIX. A Descriptive Account of the several Processes which are usually pursued in ihe Manufacture of the Article known in Commerce by the Name of Tin-plate. By Samuel Parkes, F.L.S. &c.—This is an interesting and entertaining paper. The author has a turn for describing manufactures, and the public are already indebted to him for several other manufactures of rather an interesting nature, of which he has drawn up a description. Indeed his Essays, if, in a subsequent edition, he would reduce them to half their present size, by omitting all the extraneous raatter, would be a most valuable book, and more profitable to the author than it is likely to be under its present form. The art of making tin-plate, or of covering plates of iron with tin, seems to have been established in Bohemia before it existed any where else in Europe. About the beginning of the 17th century, mines of tin were discovered in Saxony, and the Elector had the address to transplant the tin-plate manufactory to hig own kingdom. In the year 1665, when Mr. Andrew Yarrington visited these manufactories, they were of such extent as to employ about 80,000 workmen ; and the tin-plates were sent ta 206 ' Analyses of Books. (Marca, all parts of the civilized world. Mr. Yarrington went over at the expense of some public spinted individuals to learn the art of making tin-plate. On his return to England many thousand plates were made under his direction, which were considered by all good judges as superior to the Saxon tin-plates. But he and his partners were prevented from establishing a manufactory by the conduct of Charles I1. who granted 2 patent to one of his courtiers for making tin-plate. This courtier did not possess the requisite skill, and the patent prevented those who possessed the skill from establishing the manufacture. ‘The art of makin tin-plate does not seem to have been practised in England ull about 1720. A manufactory was then established at Pontypool, in Monmouthshire, where the art is still practised to a consider- able extent. The best English bar iron (prepared with charcoal instead of coke) is employed in this manufacture. It is. rolled at the mill by a peculiar process into plates of the requisite thinness. These plates are then cut by hand shears, or by machinery, to the requisite sizes. The plates are then bent mto the furm of the Greek A, and pui into a furnace, heated by flame from a fire- place of a peculiar construction, after having been previously cleansed, as it is called ; that is, steeped for four or five minutes in a mixture of muriatic acid and water, in the proportion of four pounds acid to three gallons water. In the oven they remain red-hot, standing upright on the floor till the heat takes a scale off their surface. They are then taken out, allowed to cool, straightened, and beaten smooth upon a— cast-iron block. The plates are then smoothed and polished by ee them cold between a pair of cast-iron rollers properly ardened and finely polished. These rollers are made by pouring the melted iron into a thick cast-iron box. The consequence is, that the surface loses its heat rapidly, and becomes hard, while the central part of the roller remains soft. ‘The art of making these rod/s, as they are called, is imperfect, as the process often misgives. The plates thus smoothed are steeped for 10 hours in the hes, which is water acidulated by means of bran. In the lies, the pl tes stand on their edges, and they are turned once, which is ealled working the lies. The plates, being taken out of the lies, are agitated for about an hour im a liquid composed of a mixture of sulphuric acid and water. {n this mixtere they become perfectly bright, and free from the black spots which are always con them when they are first immersed in it. When the plates come out of this pickle, they are put into "pure water and scoured in it, with hemp and sand to remove any ‘remaining oxide or rust of iron that may be still attached to them; for wherever there is a particle of rust, or even of dust, upon them, there the tin will uot fix. After being scoured, they are 1820.] Memoirs of the Literary Soctety of Manchester. 207 put into fresh water and preserved for the process of tinning ; for it has been found that they will not rust in pure water though kept'in it for a twelvemonth. - An iron pot is nearly filled with a mixture of block and grain tin in a melted state ; and a quantity of tallow or grease suffi- cient, when melted, to cover the fluid metal to the thickness of four inches is put to it. The tin is kept as hot as it can be with- out inflaming the tallow on its surface. Another pot fixed by the side of the tin pot is filled with grease, into which the plates are put, and allowed to remain an hour before they are dipped into the tin. They are then dipped into the tin pot ima vertical posi- _tion: 340 plates are usually put in at once ; and that they may be thoroughly tinned, they usually remain in it an hour and a half. They are then taken out, and laid upon an iron grating to allow the surplus tin to drain from them. But as too much tin always adheres, this excess is removed by a subsequent process called washing. A vessel, called the wash pot, is nearly filled with the best grain tin in a melted state. Into this vessel the plates are put. “This mass of hot metal soon melts all the loose tin on the surface of the plates, which so deteriorates the grain tin that after 6U or 70 boxes (a box is 22) plates) have been washed in it, the quan- tity of a block (three cwt.) is usually taken out, which is replaced by a fresh block of grain tm. When a plate is taken out, it is brushed first on one side, and then on the other, by a brush of hemp of a peculiar kind. It is then dipped once more into the wash-pot. It is then plunged into a pot filled with melted tallow, the temperature of which is carefully adjusted to the thickness of the plates. Here the excess of tin runs off, and is coilected in a wire at the bottom of the plate. From the grease-pot the plates are removed into another empty pot to cool, and’ when they are cold enough to handle, a boy, called the list boy, takes them and dips them one by one into a pot contain- ing a little melted tin in its bottom. When the wire of tn is melted, the boy takes out the plate, and gives it a smart blow with a thin stick, which disengages the wire of superfluous tetal, and this falling off leaves only a faint stripe in the place where it was attached. Nothing now remains but to clean the plates from tallow. This is done by means of bran. They are then put into wooden or iron boxes made exactly to fit them, and are ready for sale. aad XX. The Laws of Statical Equilibrium analytically investi- gated. By Mr. John Gough.—This ingenious and valuable paper is of a nature not to admit of abridgment. I am, therefore, un ler the necessity of referring the reader to the volume itself, assuring him that it will repay his trouble if he will give it a careful perusal. / XXI. Experiments on the Gas from Coal, chi-fly with a View to its practical Application. By William Henry, M.D. F.R.S.&e. 208 Analyses of Books. (Marcu, —This paper is already printed in the Annals of Philosophy, vol. xiv. p. 344. XXII. An Inquiry into the Effects produced upon Society by the Poor Laws. By John Kennedy, Esq.—The object of this ingenious paper is to defend the system of the poor laws as esta- blished in England. The author ascribes to their agency the spirit of independence, the superior comforts, and the uncommon industry, which distinguish the common people in England. He thinks that if we take into view the difference in the value of money and the great increase of the population, the poor rates are not higher in England at present than they were 60 years ago. He, therefore, conceives, that the poor rates, instead of being injurious to England, have in reality been the means of creating a spirit of independence and industry, to which the country has been indebted for its prosperity and power. I am very willing to zive the author full credit for the benevolence of his views, and the goodness of his intentions ; but conceive that his mode of estimating the advantages resulting from the poor Jaws is in a great measure fallacious. The science of political economy is much more complicated than any other. Hence it is much more difficult to draw the proper consequences from facts in that science than in any other. That England, during the last century, made prodigious advances in wealth and power is admitted by every one. The question is to what are we to ascribe these advances? Some have ascribed them to the free- dom which the inhabitants of this island enjoyed; some to the successful wars which were carried on in the course of the century, which enabled England to cripple, and even annihilate, some of the most lucrative branches of trade and manufactures carried on by our rivals ; some to the erroneous policy and mis- government of the other European states; some have even ascribed the progress of England to the monopolizing laws esta- blished by the influence of our manufacturers ; and some have been bold enough to ascribe it to the increase of taxation ; but our author, so far as I know, is the first person who has ascribed it to the influence of the poor rates. He allows that the present system of poor laws is liable to abuses that cannot be easily checked. This alone is an objec- tion, which appears to me decisive. He thinks the poor in England are better fed, and enjoy much greater comforts, than the poor in Scotland. If by poor be meant those persons who are supported by the parish, the statement, for any thing that L know to the contrary, may be true; but if by poor be meant, according to the usual acceptation of the term, the class of people who are obliged to labour for their maintenance, 1 have some reasons for doubting the accuracy of the assertion, The expense of living is not greater in Scotland than in England, and yet the wages of farmers’ servants is considerably higher in Scot- land than in England. A Scotch farmer’s servant then has the 1820.] Memoirs of the Literary Society of Mancheste~. 209 means of living better than the same class of persons in England. It is true that his style of living is different He does not indulge in the large draughts of beer which an English hind cannot do without, and which in reality constitutes the greatest part of his food; but he has a liberal supply of milk, which, in My opinion at least, is a far better beverage. He is not in the habit of wasting the whole of his income upon his immediate subsistence. He endeavours to lay up a little for old age, and he has frequently an old father or mother whose support has devolved upon him. Now! leave our author to determine which of these two modes of living is likely to foster the most indus- trious habits and the most independence of spirit. In the south of England at least, for I have not had the means of witnessing what is the practice in the north of England, the wages of the farm servants are so low that the deficiency is partly made up by the parish, and farmers are not in the habit of hiring them by the year but for very short. periods. Now if living upon the parish be the way to acquire independence of mind and a sense of one’s own dignity, it must be acknowledged at least that the medicine in general is very unpalatable. Our author says that the poor rates lower the wages of labourers, and enable the manufacturers to produce their cotton and their calicoes at a cheaper rate than they otherwise could do. Of course, says he, it is the interest of the manufacturers’ to uphold the poor rates. Now as far as the manufacturers are concerned there is something in this argument. When turned into plain English, it will stand thus: Part of the wages of manufacturing labourers is paid by the country in general (by manufacturers, landed proprictors, farmers, &c.) whereas, if there were no poor rates, they would be all paid by the manufac-' turers themselves. Therefore it is for the imterest of the manufacturer that the poor rates should continue ; so that the poor rates act as a bounty on manufactures. So far they are really injurious to the country by enabling manufacturers to geet in making several articles after they have ceased to e profitable. In reality, as far as the labourers of manufac- ‘turers are paid by means of the poor rates, the money so bestowed is given away to those foreign countries who purchase our manufactures ; and England would be just as much richer as she is by the amount of the poor rates thus given to the labouring manufacturers, if these manufactures were not cultivated in the country at all. XXII. Memoir on Sulphuric Ether. By John Dalton. XXIV. Observations on the Barometer, Thermometer, and Rain, at Manchester, from 1794 to 1818 inclusive. By John Dalton. : The first of these articles was given cr.tire in our last number ; the second is reserved for our next, wou. AV. No UT. O 210 Proceedings of Philosophical Societies. [Marcn, Articus VIII. Proceedings of Philosophical Societies. ‘GEOLOGICAL SOCIETY. Dec.3.—A paper was read by the Rev. Professor Buckland, of Oxford, On the Quartz Rock of the Lickey Hill, near Broms- grove, and Strata immediately surrounding it, with Considera- tions on the Origin of Quartzose Pebbles of the Plains of Warwickshire, and of the Valley of the Thames from Oxford downwards to London. ' The group of the Lickey Hills is described in this paper as occupying a small district between Bromsgrove and Birming- ham in the middle of an extensive tract of young red sandstone, At the Lower Lickey this sandstone suddenly ceases, and a, long hill composed of granulated quartz rock projects to a consi- derable elevation above the plains of sandstone that flank it on the east, forming a narrow camel-backed ridge of about two miles in length, from north to south, and a quarter of a mile in breadth. On each side of this ridge is a small deposit of shat- tered strata, belonging to the coal formation, and near the extreme points ofits north base are two minute patches of tran- sition limestone. At its south end there is also a small portion of trap rock, and near its north-east base there occur traces of cornstone and old red sandstone. These fragments, together with the ridge of quartz rock, are encircled by an investiture of horizontal strata of young red sandstone, the beds of all. the other formations being highly inclined. The upper Lickey Ridge, which overhangs all these fragments of older formations on the west, contains a higher elevation than any of them, and is composed of strata belonging to the young red sandstone formation, containing subordinate beds of pebbles derivative from the quartz rock. _ The ridge of quartz rock constitutes the most important feature of this group, and is probably referable to a place among the oldest members of the transition series, being exactly cf the same character with the quartz of the summit of the Stiper stones, and the Wrekin and Caer Caradoc, in which two latter places, it lies beneath greywacke slate, and is incumbent on greenstone. The quartz at the Lickey is distinctly stratified, and is natu- rally shivered or split into millions of small angular fragments ; this circumstance is important, as showing the facility with which a rock so constituted, may have been broken down by the force of water, and have contributed to form those enormous beds of siliceous pebbles which occur in the lower strata of the young red sandstone formation in the midland counties of Eng- 1820.] — Geological Society. — 2h1 land. Other pebbles that are mixed with them in the same strata are probably derivative from the rocks of Charnwood Forest. The destructibility of this rock, in consequence of its shattered and minutely divided state, affords a reason why those few portions of it which we find in the Lickey and at Caer Caradoc and the Wrekin, are almost the only remaining frag- ments of a formation which the abundance of its wreck proves to have occupied a very considerable space before the deposition of the strata composing the young red sandstone formation. Several places are specified in the neighbourhood of Bridgnorth and Kidderminster where these siliceous pebbles may be seen forming part of, and imbedded in, the regular strata of the young red sandstone formation. ' In the same neighbourhood, and indeed universally over the central plains of England, the same pebbles occur mixed with other pebbles of almost every kind of English rock from granite up to chalk, in the form of superficial gravel torn by the last diluvian waters that have affected the earth from every substance that lay within the influence of their currents, and drifted toge- ther without any reference to the age or condition of the subja- cent strata on which they are now accumulated. The extent of this gravel is not limited to the central plains ; it has been drifted on within the area of the oolite formation by two depressions or low lips in the high escarpment of the Cots- wold hills, and has passed down the Even-lede and Charwell towards Oxford. . The table-lands on each side the valley of Even-lode are scattered over with those pebbles, and on the highest summit of Witchwood Forest, Wytham Hill, and Bagley Wood, on the north-west of Oxford, thick lips of gravel composed of these pebbles from Warwickshire, are accumulated on the surface of strata belonging to the oolite formation. The position of these summits is exactly opposite the point where the valley of the Even-lode falls into that of the Thames, and where the diluvian currents descending the former valley would evacuate their driftings. Similar pebbles occur in the gravel of the summit of Henley Hill and in the gravel beds of the valley of the Thames, from Oxford downwards to Hyde Park. But above that point where the driftings of Even-lode Gorge, fall into the valley of the Thames, no such deposits of siliceous pebbles are to be found along the course of the Salter riyer from its head springs on the south side of the Cotswold Hills. There; 1s a-considerable proportion of chalk flimts mixed up with the gravel we are considering; and the fact of its containing pebbles of hard white chalk and of red chalk, such as occurs in no part. of the chalk of the south-east of England, but is common in the lower strata of this formation, in Lincolnshire and Yorkshire, goes far to show that these red pebbles and chalk flints. have 0 2 “ 212 - Proceedings of Philosophical Sccieties. [Mancn, been drifted south-westward, probably from Lincolnshire, over the plains of Leicestershire, subjacent to the great oolite escarpment. It is certain the quartzose pebbles cannot have been drifted from any part of England south-cast of the escarp- ment, since there is no stratum in this portion of the island from which they could possibly have been derived. It is stated that these quartzose pebbles, which were derived primarily from the Lickey quartz rock, received their rounded form at a period pre- ceding the deposition of the young red sandstone strata, from which they were again torn up and mixed with fragments of other rocks, and scattered over the surface of all formations that lay in the course of the latest diluvian currents that have affected the earth. The completely rounded flint pebbles of Blackheath and of the Hertfordshire pudding-stone are also stated to have received their attrition at a period intermediate between the deposition of the chalk and plastic clay formations, and long -_ anterior to the action of the last great diluvian waters. And both these pebble beds of ancient origin have shared the common fate of all formations in being torn up by the waters of the last great deluge, and mixed up with the less perfectly rolled fragments of rocks that have undergone no further attrition than that to which they were submitted in being washed by it from their native station to the gravel beds they now occupy. An examination of the compound character of the gravel beds of Kensington and the valley of Oxford is brought forward in proof of the statements above advanced. At Kensington, we have the ancient pebbles which existed as such in the regular strata of Warwickshire and Blackheath mixed up with the angular and imperfectly rolled chalk flints. which constitute the mass of that gravel, and have been sub- mitted only to the action of the last great deluge. And at Oxford we have the same Warwickshire pebbles mixed with the angular and slightly rolled fragments of oolite and other rocks which form the hills intermediate between Warwickshire and Oxford. Arguments are also adduced to show that the lower trunks of the valleys of the Thames and Even-lode, i. e. those portions of them which le between the table lands that flank the course, did not exist at the time of the first advance of the diluvian waters which brought the pebbles from Warwick- shire, but were excavated by the denuding agency which they exercised during the period of their retreat. Dec. 17.—The conclusion of a paper was read, which had been begun last session, “ On the Coal Fields adjacent to the. Severn,” by Prof. Buckland and the Rev. W. D. Conybeare. ~ Of these coal fields the first selected for description is that which they have termed the Somerset and South Gloster Basin. It is called a basin only with reference to the general position of the strata, comprising its interior, since these strata are affected by many minor undulations which at first sight appear to divide ~ . 1820.) Geological Society. 213 it into several smaller basins and irregular concavities which may be considered subordinate to the general structure of the district. This district occupies a triangular area bounded on the south by the Mendip hills, and on the other two sides by lines drawn from the two extremities of the Mendip chain to the village of Tortworth, in Gloucestershire. The exterior ridges which bound the area of this coal forma- tion consist for the most part of an interrupted chain of mountain limestone reposing on old red sandstone ; and these two forma- tions are so closely associated, that in describing their geogra- phical extent, it is necessary to treat of them in combination. Of these extensive ridges, the Mendip chain is most important - in extent and elevation ; it consists of a central axis of old red sandstone, flanked by a double line of mountain limestone; the sandstone strata, however, are not visible in one continuous line; but present themselves in a series of four ridges, forming the - four most elevated parts of the chain, though not exclusively confined to them. Each of these ridges forms a saddle-shaped nucleus of sand- stone, usually inclined at an angle exceeding 45°, around which the incumbent beds of limestone are wrapped as a mantle dipping _ in every direction, conformably to the subjacent sandstone. Between the sandstone and mountain lime is interposed a bed of shale, in which several fruitless attempts have been made in search for coal: this bed it is proposed to designate as the lower limestone shale.. The Mendip chain is thus divided into four regions, each containing as its nucleus one of the ridges of old red sandstone. The most easterly of these is the ridge of Masberry Castle, - near Shepton Mallet; the east central is Pen Hill, near Wells ; the west central, Priddy North Hill and the western Blackdown, near Cross. The total length of the Mendip chain is about 26 miles run- ning east and west from near Frome to Uphill, on the Severn; on the south-east flank of this chain a curious circumstance is exhibited in the contact of overlying horizontal beds of ‘lias and inferior oolite, with the inclined strata of mountain lime and old red sandstone, several small rivers in this part exhibiting roman- tic clifis of mountain lime in highly inclined strata, crowned with horizontal beds of oolite. These strata sometimes adhere to each other as firmly as if they had been parts of one and the same contemporaneous formation. The detail of the description of the subdivisional ridges of the Mendip chain is too minute to allow of abridgment. The mountain limestone corresponds in all its characters with that of Clifton, and has its usual properties of engulphing rivers, and exhibiting extensive caverns and abrupt romantic precipices, the most remarkable of which are at Chedder cliffs. The old 214. Proceedings of Philosophical Societies. [Maren, red sand throughout this chain is characterized by a degree of sterility as remarkable as that of its fertility in the countries of Monmouth and Hereford: this arises from its being composed in Mendip of a hungry, siliceous grit, alternating with beds of brown tenacious clay; and being deficient in those beds of marl coloured by red oxide of iron, which give their extraordinary fertility to the last two named counties, and which extend their influence to the similarly constituted strata of the young red sandstone and red rock marl formation. Jan. 7, 1820.—The continuation of a paper was read, “ On the Coal Fields adjacent to the Severn,” by Prof. Buckland and Rev. W. D. Conybeare. The southern boundary of the triangular area of the Somerset and South Gloucester coal field, having been described as con- stituted by the entire chain of the Mendip hills, it remains to examine its west and eastern border, and afterwards to proceed to the history of the coal field itself. On the west border, the old red sandstone and mountain lime- stone do not, as in the Mendip chain, form a continuous unbroken frontier, but occur in the detached groups of Brondfield Down, Leigh Down, Derdham Down, Kings Weston Down, and the -ridgway near Almondsbury, extending thence to Tortworth, which is situated on the north apex cf the area under consider- ation. The strata of mountain lime composing Brondfield Down dip in every direction from the centre to the circumference, as is expressed on the map by arrows and figures ; its south hangings are covered by beds of calcareous conglomerate, some of which are crowned with caps of lias. The west side of Brondfield Down, being also the steepest, is intersected by three magnificent gorges, resembling Chedder Cliffs ; of these Brockley Comb and Gobble Comb are the most important; the latter has a strong resemblance to Dovedale, in Derbyshire. In a trough oflimestone between Brondfield Down and Leigh Down is situated the small ccal field of Nailsea, which is a kind of satellite exterior to, and attendant on, the great coal basin, to the edge of which it is externally adjacent. The chain of Leigh Down extends from Clevedon on the Severn to the gorge of the Avon, near Clifton; it dips south, and has beds of old red sandstone forming the base of the escarpment of its east portion; nearly parallel to this chain on its north-west side is a similarly constructed ndge called Weston Down, having a similar dip ; and in the valley between them are the shattered strata of the coal field of Clapton reposing on the limestone of Westcn Down, and touching the buse of the escarpment of the west portion of Leigh Down; an extensive fault occurs along the base of this portion of Leigh Down, and brings the coal measures into contact with the basset edges of the limestone. : 2-64 ‘ 1820.] Royal Academy of Sciences. 215 The base of Leigh and Weston Down, and the valley situated. between them and the Avon, are, for the most part, covered with horizontal strata of magnesian conglomerate. The west boundary of the main coal field is continued on the other side of the gorge of the Avon in the calcareous chain that winds round the south-east and north sides of the vale of West- bury, and constitutes Durdham Down, Henbury, and Kings Weston Down. The fundamental part of this valley is old red sandstone, the truncated edges of which are, for the most part, covered by horizontal beds of magnesian conglomerate; the dip of the old red sandstone ard limestone is outwards im every direc- tion from the axis of this valley. The next group of mountain lime and old red sandstone along the west frontiers of the main coal field is that which extends from the ridgway near Almondsbury to the village of Tortworth, and which dips regularly towards the interior of the coal basin with a few partial exceptions. The intermediate space between Almondsbury and the West- bury group shows only beds of the lias and young red sandstone formation, which on this side intrude largely within the coal basin, extending to Stoke Park, on the edge of the Kingswood collieries, and, in all probability, covers up considerable tracts of coal; this lias seems to have been once connected with that of Pucklechurch and Sodbury, covering the whole South Glou- cester coal, from which it has been since partially removed by denudations. At Tortworth the calcareous chain of the west frontier reaches the point where it is suddenly deflected southwards at an acute angle, and from which it may be traced with certain interrup— tions along the east frontier of the great coal basin to the. Mendip hills, near Mells. Near Tortworth, beds of transition lime are protruded from beneath the old red sandstone, and are intersected by two dykes of trap. We also find there a few traces of coarse greywacke slate. ROYAL ACADEMY OF SCIENCES AT PARIS. An Analysis of ihe Labours of the Royal Academy of Sctences ~ during the Year 1818. (Continued from p. 65.) REPORTS APPROVED OF BY THE ACADEMY. Experimental Researches upon Lime for Building; by M. Vicat.—As the whole of this important report will be printed in an early volume of the Memoirs, we shall now only transcribe the conclusion of the report of the committee, Messrs. de Prony, Gay-Lussac, and Girard, Secretary. “This work engaged the attention of your Committee both on account of the.new facts it ccntains, and the order and clearness. 216 Proceedings of Philosophical Societies. [Marew, with which they are related. The explanations given of them are founded on sound theory, and prove that the author, although he resides in a distant department, has yet constantly kept paee with the progress of the sciences, and is very capable of deduc- ing useful applications from them. No one can fail to conduce to this progress if, with such a spirit of inquiry as appears to animate M. Vicat, he endeavours to enlighten with his know- ledge the art in which he is employed, and engineers who are placed in similar circumstances in different parts of the kmgdom,, are under obligations to him both for the results of the work he ‘offers to them, and the example he offers them.” We think,. therefore, that this work does in every respect merit insertion in the Recueil des Savans Etrangers. Euclid in Greek, Latin, and French ; by M. Peyrard.--Com-. mittee, Messrs. de Laplace, Legendre, Prony; and Delambre, Secretary. This third and last volume contains the 11th, 12th, and 13th books of the Elements, the book of the data; and, lastly, the two supplementary books on the regular solids which are not really by Euclid, and are generally attributed to Hypsicles of Alexandria. The editor has thought it right to apologize for ‘having republished these two books, which he does not appear to esteem very highly ; he is in our opinion not only sufficiently ‘justified by the example of so many other editors, one of whom even thought it right to add a new supplement to those of Hyp- sicles ; but we may say that these books are a necessary conti- ‘nuation of the 13th book of Euclid, who had merely touched upon the theory of regular solids. In fact, Euclid contented. “himself with settling the edges of these bodies without saying a word about the mutual inclinations of their surfaces, or the distance of these surfaces from their poles, or from the centre of ‘the sphere, nor does he speak of the surfaces or of the bulks of the five regular solids, Hypsicles has not, however, entirely exhausted the subject, he merely gives the surfaces of the dodecahedron and the icosa- hedron, he determines their proportions, which is also that of _their bulk, since the surfaces of these two bodies are at equal “distances from the centre of the sphere—a remark which he might have extended to the hexahedron and the octahedron, as has been done by one of his continuators. The subject of the inclinations is treated of more fully. In order to determine them, Hypsicles begins by explaining the general construction of his celebrated master, Isidorus. The _matter appeared so evident to that geometrician that he thought it unnecessary to add any demonstrations. At first sight, it might be imagined that Hypsicles wished to render it obseure while demonstrating it, but from every appearance Isidorus had, when he invented his constructions, the figures in relief af all the regular solids. With this assistance, which M. Peyrard -1820.] . - Royal Academy of Sciences. 217 also procured, nothing is required but the use of our eyes to be convinced of the perfect accuracy of these methods; we may then easily comprehend the figures traced by Hypsicles, and the demonstrations become clear. M. Peyrard accuses these demonstrations of being deficient, both in exactness and in elegance. We allow they are much too long, but that fault ought not to be thrown on Euclid, who, we know not why, has determined the inclination to be the acute angle formed by two contiguous surfaces. In reality the inclination is never an acute angle, except in the tetrahedron : it is a right angle in the hexa- hedron, and an obtuse angle in the other three solids, so that an acute angle is not to be found in the hexahedron, and in the three other solids, it is the angles between one surface and the prolongation of the neighbouring surfaces that are acute. Now half the demonstrations of Hypsicles are devoted to settling the - species of angles, whilst the constructions of Isidorus always give the true angle, whether acute, or obtuse, so as to preclude the - possibility of any mistake. We may add that these demonstrations, although they are different for each of the five regular solids, yet depend upon one single principle, which would render them clear, even indepen- dently of the figure in relief. This principle consists in suppos- ing in each solid a line to be drawn, which would serve as a common basis to two isosecles triangles, whose sides are known. In one of these triangles the angle at the summit is always known ; in the other, it is the inclination which we seek for; a very simple relation between the cosines of the two angles is the result of this ; and if we apply to these triangles, one of the rules of our modern trigonometry, we immediately obtain an equation exactly similar to that which is furnished by spherical trigono- metry. But this modern rule was entirely unknown to Euclid, to Isi- -dorus, and to Hypsicles, who, in the very defective solution which he has elsewhere given us of a problem resolved nearly at the same time by Hipparchus, has left us a striking proof of his - complete ignorance of both plane and spherical trigonometry. It is rather remarkable that this theory of regular solids, per- - plexed and imperfect as it was with the Greeks and their continuators, should depend entirely upon a rectangular spherical triangle, traced on the surface of the sphere upon which we wish to inscribe at once all these solids. The angles of this triangle are always given, and the formule resulting from them for the three sides furnish the most simple expressions of the edges of . the polar distances ofall these planes of their mutual inclinations, -of their distances from the centre of the sphere ; and, lastly, of the metheds of measuring with equal facility the surfaces either partial or total, and the bulks of the five regular solids in parts of - the radius of the sphere taken as unity. - “This triangle not only gives the precise and numerical quantity ‘218 Proceedings of Philosophical Societies. [Mancn, ‘of ithe inclinations, which was beyond the geometry of Euclid, but it also supplies the most simple relation to determine the nature and the number of the regular solids which can be inscribed im the same sphere; so that a single triangle, a single formula, serves for all.. This will be demonstrated by one of us in the ‘ History of Modern Astronomy,’ at the Article Kepler, who wished to prove, by means of the five regular solids, that no other planets than those known from time immemorial could exist. «« Another observation, not less curious or new, is, that the general trigonometrical expressions (the most expeditious that can be imagined for logarithmic calculation) may be transformed with wonderful facility imto those irrational expressions which the. Greeks call major, minor, and: epotome. In fact all the primitive angles are of 30°, 36°, 45°, 54°, 60°, and 90°, whose trigonometrical lines are irrational, and lead directly to the con- structions of Euclid and of Isidorus. The consequence of this is, that the unknown parts of each problem may be expressed at our:option by the sines, cosines, and tangents, either of the arc or of its half, so that we have always six: diiferent expressions for every one, and among so many expressions, we may always select the most convenient; the calculation is also shortened still more by the circumstance that there is scarcely one of these quantities which is not to be found again in another of these solids ; so that there are never more than four calculations in the whole to make for the 15 unknown quantities of the general problem. In this way, after having completed and simplified the constructions of Euclid for the five edges, we have succeeded in forming more easy and uniform constructions than those of Isidorus, in rectilinear isosceles triangles, whose common basis is the diameter of the sphere. “We, therefore, think we may differ in opinion from the trans- lator, and consider the two Books of Hypsicles as a curious remnant of the ancient geometry, imasmuch as they contam notions that are not to be found elsewhere. The most important points are, to obtain true theorems, and faultless constructions. -As for the demonstrations, they likewise are of importance, doubtless ; but should we be dissatisfied with them,’ we may, without much difficulty, find others. The principal defect of those of Hypsicles has already been mentioned; it is, that the first half is in every one of them quite useless. ‘ “It is true that the demonstration of the second proposition in the second Book was. perfectly unintelligible ; but we may be allowed to conjecture that only the copyists are to blame. -M. Peyrard has given a new one, which may probably have been originally the author’s. There is also a demonstration of Euclid which all. commentators had agreed to look upon as altered, or as quite deficient. Itis one of the most important propositions in the book of data, and may be reduced to an 1820.] © Royal Academy of Sciences. 219 equation of the fourth degree, which is solved nm the same way as those of the second. M. Peyrard begins by giving the alge- braic calculation of it; afterwards, by .translating the Greek demonstration into the modern style, he renders its strict and accurate progress more forcibly evident. , «Amongst all the propositions contained inthis last volume, not one occasioned the editor so much trouble as the 17th of the 12th Book of the Elements. In all manuscripts and editions whatever, the figure was so defective, that most of the reason- ings of Euclid were quite inapplicable toit. The translator has, by means of adding some lines, rendered the demonstration exact in every respect. : “« There is, in every other part, as in the preceding volumes, the most perfect fidelity in the translation, and the same care is taken to correct the text, and to collect the various readings, which here form 84 pages. The editor had asserted that. the fine Oxford edition was not more correct than that of Basil, since, besides republishing all the errors, even the most palpable, of the latter, the former contained a considerable number of other faults, from which the Basil edition was free. This state- ment excited astonishment, and was probably but little credited; yet we cannot perceive what can be objected to the eight pages in which M. Peyrard has exhibited a comparative view of the two editions. i3 “M. Peyrard has now brought a long and laborious work toa successful conclusion. We propose to tue Academy to extend the same approbation it has been pleased to bestow on the two others, to the third volume, in the hopes that this merited approbation may facilitate the publication of the author’s Apol- lonius, the manuscript of which has long since been finished.” We have much pleasure in announcing that this new edition is begun, and that we have already seen several sheets of it. A Treatise on Descriptive Geometry; by M. Vallée, Civil Engineer.—Committee, Messrs. de Prony, Fourier, and Arago, Secretary. The lectures on descriptive geometry of the celebrated author of that doctrine, M. Monge, contain an explanation of the principles of the science which will always be cited as a perfect model of perspicuity. It is to be regretted that the work is not more extensive, for artists who have not made a particular study of mathematics cannot familiarize themselves with the methods of projection, without varying the data of the ques- tions, and practising upon a great number of examples. M. Hachette has partly filled up this chasm by a supplement, which obtained the approbation of the Academy. By following the footsteps of these two scientific men, M. Vallée has com- piled his treatise, which he divides into six books, forming more than 500 pages in quarto. “The Committee, who devoted their attention chiefly to the:most difficult parts, feel pleasure in “920 Proceedings of Philosophical Societies. [Marcn, ~acknowledging that they are composed with much order and ‘clearness. The 59 plates accompanying the text are perfectly ‘well drawn. Each diagram presents even to the minutest par- ticular every construction that it is necessary to execute, in order to obtain the solution of the problem, and yet there is not the least confusion. In a word, this work appears to us, in ‘every respect, worthy the approbation of the Academy. We wish this skilful engineer may receive from government such “encouragement as will enable him to publish his work, and also that he may finish those he has already undertaken, and which are to contain the applications of descriptive geometry to the arts of the carpenter and of the stone-cutter.” A Treatise on Surveying ; by M. Puissant. Second Edition. —-The first edition of this work having been speedily exhausted, the author has, in preparing the second, enriched it by some important additions. La Base du Systéme Métrique, la Meca- mique Celeste, and the Memoirs of M. Legendre, are the fruitful mines from whence he has frequently drawn. It would, how- ever, be wrong to suppose that, even in those cases, he has merely acted the part of a copyist, the new and elegant demon- ‘strations which he gives of the already known formule, and the connexion he has established between theories, that had often been presented separately and by different geometricians, prove that M. Puissant had, before he took up the pen, deeply studied the methods of geodesy. The Committee are of opinion that the -new work of this skilful engineer deserves, in every respect, the approbation of the Academy. Model of a Machine for raising Water by the combined Action of the Weight of the Atmosphere on the Surface of the lower eservoir, and the Refluw of that Water in an ascending Pipe, inserted in a Kind of intermediate Reservoir, filied by Means of the Vacuum occasioned in it by the said Mechanism ; by Messrs. Lacroix and Peulvay.—Committee, Messrs. de Prony, Charles, and Girard, Secretary. The Committee begin by explaining by what means the want of the usual pistons, valves, and suckers, have been supplied. _ From the description they afterwards give of all the parts of the machine, and the methods of bringing it into action, they con- clude it may be reduced to a sort of wheel furnished with a certain number of wings, capable of opening as they turn round to form successively as many partitions. The idea of this sort of pump appears to them very analogous to a plan that Conté car- ied into execution 12 years before his departure for Egypt. They even think the machine of Conté was rather more simple ; the new model nevertheless proves the artists to be ingenious and intelligent. If the invention be not as new as they seem persuaded of, yet it cannot be denied that their sucking and forcing pump may, in certain cases, be advantageously substi- tuted for the common pumps, and that the authors have 1820.] Royal Academy of Sciences, _ 221 displayed talents that deserve encouragement. They add, that in the Description des Machines de Serviere, there may be seen an account of an apparatus constructed in the house of M. Lenoir, Faubourg Saint Antoine, in which may easily be perceived a close resemblance to the machines of Conte, and Messrs. Lacroix and Peulvay. Notice relative to Iron Railways ; by M. Gallois —Committee, Messrs. de Prony and Girard, Secretary. It has long been the custom in some parts of Germany to make, for the purpose of working mines, roads, or carriageways, formed of longitudinal pieces of wood, on which were drawn, through the galleries, carts, appropriated to that sort of convey- ance. Since then a plan has been invented in England of substituting for these pieces of wood, roads, or ways, made of cast iron. M. Gallois has undertaken to describe them more fully than has hitherto been done, and to estimate their advan- tages as compared with those of common roads and navigable canals. {t is in the neighbourhood of Newcastle that iron railways are. particularly numerous. According to the author, an extent of 28 square miles on the surface of the earth presents a series of 75 miles of them; while the interior of the coal mines contains them to as large an amount. Five or six waggons, made entirely of iron, fastened to each other in regular succession, descend these roads without any other mover than their own weight. By means ofa pulley, or wheel, a certain number of carriages in descending occasion a certain number of others to mount, in order to unload, or to take in a load at the summit of the inclined plane they traverse. The principal object M. Gallois appears to have in view consists in displaying the advantages the iron railways, so frequently to be met with in England, have over common roads and navigabie canals. We are naturally led to believe that, excepting in very peculiar circumstances, there will always be agreat saving of power in conveyances by water, for this simple reason, that the whole weight of the burden so transported 1s supported by the stream, while the inclined plane upon which the carriage runs supports only a part of its weight. On the other hand, it cannot be denicd that many situations in which it would be quite impossible to open a canal, might admit ef the establishment of railways of wood or of iron. 'l'o diffuse the knowledge of their construction is supplying our industry with new sources of employment. But previously to their employment, it would be necessary to render the casting of iron less expensive. This important object has particularly fixed the attention of M. Le Gallois. His notice on iron railways is one of the most useful results of the researches in which he has been engaged during his stay in England ; and, in our opinion, the Academy ought to encourage its publication, 4 Methods of cutting out Garments ; one by M, Beck, tailor at 222 Proceedings of Philosophical Societies. [Maren, Paris; the other, by M. Chomereau, tailor at Brie-Comte-. Robert.— Committee, Messrs. de Prony and Molard, Secretary. The following is the conclusion of the report : ‘“ It is possible that Messrs. Beck and Chomereau may have been anticipated on some points by those who have treated of the same subject before them, but we are not the less obliged to them for their efforts to submit the art of the tailor to rules that tend to render perfection and economy compatible. We think their zeal and their talents deserve praise from the Academy.” « Essay upon a general Principle in Mechanics ; by MI. Binet.— Committee, Messrs. De Laplace, Poisson, and Fourier, Sec. “« The author principally considers the proportion between the powers and the areas described by the radii vectores, round a fixed centre. He denominates the fluxion of the area traced by the radius vector the areolar velocity, to distinguish it from the linear velocity, which the moving body actually describes in its trajectory line. He calls the sum of the products of the masses by the squares of these areolar powers the areolar vis viva, and determines the mathematical relation of these quantities. Ifthe power that acts upon a moveable point be represented by a right line given in magnitude and position, and there be drawn upon this-line, as on a base, a triangle, whose summit represents the fixed centre, this figure will represent the force of rotation, the ig of the triangle being that in which it exercises its action. f the moveable body passes from the place it occupies into another infinitely near, its radius vector will describe an infinitely small area, the plane of which may differ from that of the rotary power. If on this last plane the area described is projected, the projection will represent the virtual effect of the force of rotation estimated in the very plane of that force. This being done, it may be enunciated as if it were the principal result which the author attained. “ If the quantity of each force of rotation be multiplied by its virtual effect, and if all the similar products be added, the sum will represent the instantaneous increase of the whole vis viva, relatively to the areas described, or the sum of the products of each mass by the square of the velocity by which the area was increased. By thus determining the element of the total vis viva for every instant which follows, and by adding those ele- ments together, the integral will express the increase that the vis viva receives during any given time. “This proposition is entirely similar to that which expresses the linear vis viva. The same analysis that shows what these propositions have in common, shows also in what manner they differ. Kepler, to whom we owe the discovery of the elliptic motions of the planets, found at the same time, by an assiduous comparison of observations, that the radius vector of a planet described areas proportional to the times. Newton afterwards ascended from the knowledge of the mathematical laws deduced 1820.] Royal Academy of Sciences. 293 from observations to that of the physical cause of the phenomena. He saw that this equality of the areas necessarily shows the power that retains the planet in its orbit to be directed towards the sun. Thus every one of Kepler’s laws became a theorem in dynamics. D’Arcy, Bernouilli, and Euler, well knew that if the areas were drawn upon any plane, the sum of the areas, measured in one direction, would augment in proportion to the time elapsed.” ‘ Here the Committee mention in an abridged manner the theo- rem of Newton relating to the conservation of the centre of gravity ; that of M. De Laplace concerning the plane of the maximum of the areas, the researches of Euler concerning the measure and composition of the momenta. ‘ The propositions relative to this composition, and many new theorems concerning the same subject, are expressed in the clearest and the most elegant manner in the ‘lreatise, and the Memoirs which M. Poinsot has published upon Statics. . Every one of these results are to be found in them, deduced by a plain method peculiar to him, which has the advantage of rendering them easy toy be perceived, and of proving, in a direct manner, that the forces of rotation are decomposed, distributed, and destroyed, accord- ing to rules entirely similar to those which concur in the forces of translation. The exposition of the properties relative to areas, which Laplace has given in his Mecanique Analytique, ought to be added to this enumeration. *« M. Binet’s method consists in deducing from the differen- tial equations of the motion, the expressions relative to the areas produced, and to their fluxions of the first and second order, -by proving that the expressions combine among themselves in the same manner as those of the ares described by the moving body, and those of the velocities. This analogy between the areas and the trajectories may be considered in another point of view; in reality, if we suppose that, in the general equation which shows, the sum of the projected areas to increase in proportion to the times, the centre of the radii vectores is placed at an infinite distance from the origin of the coordinates, we shall see directly that the velocity with which the’ sum of the areas increase is the velocity with which the centre of gravity of the system departs from a fixed plane. And in this manner the theorem concerning the motion of the centre of gravity is deducible from that of the preservation of the areas. The case is the same in regard to the equation which expresses the three parts of the vis viva of rotation. “The latter end of the memoir presents an ingenious collection of several general theorems of mechanics. In order to show that these propositions arise from one common source, the author adds to them the differential equations of the motions, multiplied by the coefficients which the variable quantities may contain, and their differentials of the first order. He proposes to 224. Scientific Intelligence. [Marcu, determine these coefficients so that integrable expressions may be obtained. By this means a general result is obtained, which produces the theorem relative to the motion of the centre of gravity, that of the areas, that of the vis viva, and, lastly, the one which the author has demonstrated.” “< The researches which tend to bring general mechanics to perfection are interesting not only to the arts, but also to the study of nature. It is upon these accounts that the Committee judge the work of M. Binet worthy of the approbation of the Academy ; as well for the choice of the subject, as for the man- . ner in which the subject is treated ; and propose the printing of - the memoir in the collection of foreign papers.” (To be continued.) ArTICLE IX. SGIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS CONNECTED WITH SCIENCE. I. Protoxide and Deutoxide of Azote. Ir seems to have been proved ina satisfactory manner by Gay- Lussac, that deutoxide of azote or nitrous gas is a compound of 1 volume of oxygen gas + 1 volume of azotic gas united toge- ther without any change of bulk ; so that the specific gravity of deutoxide of azote must be the mean of that of oxygen gas and that of azotic gas. Specific gravity of oxygen gas...... ee 8 Specific gravity of azotic gas. ...... 0°9722 2) 2:0833 Specific gravity of deutoxide of azote = 10416 A set of careful experiments made in my laboratory gave 1-043 as the specific gravity of this gas. Now this comes within _,4,th part of the theoretical number—a coincidence which I consider as sufficiently near to satisfy us of the truth of Gay-Lussac’s hypothesis. From the most careful experiments hitherto made upon the protoxide of azote, there is reason to consider it as composed of one volume of azotic gas, and half a volume of oxygen gas, con- densed into one volume ; for this gas is completely decomposed when mixed with its own volume of hydrogen gas, and an elec- trical spark passed through the mixture. There remains after the combustion a quantity of azotic gas exactly equal to the original bulk of the protoxide of azote employed, Let the volumes of the two gases burned be as follows ; 1820.) - Scientific Intelligence. 295. Protoxide of azote. .........-. 100 volumes Hydrogen ..........0..0.00% 100 After the combustion there will remain a quantity of azote making 100 volumes. Now 100 volumes of hydrogen for com- plete combustion require 50 volumes of oxygen. From this it is obvious that 100 volumes of protoxide of azote are composed of AZOUE BAS. 66. ete eee ee wees 100 volumes Oxygen gas .-.. cess seen eee - 50 condensed into 100 volumes; or, which is the same thing, of one volume of azote and half a volume of oxygen condensed into one volume. Hence we must obtain its specific gravity by adding half the specific gravity of oxygen gas to the specific gravity of azotic gas. Specific gravity of azote. .......... 0°9722 Half specific gravity ofoxygen...... 0°5555 Specific gravity of protoxideofazote= 15277 Now Colin found the specific gravity of this gas 1°5204, and a careful set of experiments made in my laboratory gave the specific gravity of this gas 1-5269—a number which is much less than —,',th part from the theoretical number. There seems then no reason to doubt the accuracy of the opinion, that this gas is a compound of a volume of azotic gas and halfa volume of oxygen gas condensed into one volume. Azote. Oxygen, Nitrous gas is formed of 1 vol. + 1 vol. constituting 2 vols. Protoxide of azote .... 1 a Ae ee. a There seems no reason, therefore, to doubt that if nitrous gas could be deprived of half its oxygen, it would be converted into protoxide of azote, and that, by this abstraction, its bulk would be reduced exactly one half. But upon putting this apparently accurate conclusion to the test of experiment, the result turns out considerably different from what would be expected. Every chemist is aware of the fact that nitrous gas is converted into protoxide of azote by keeping in it a quantity of moistened iron wire. The fact was first observed by Dr. Priestley, and led to the original discovery of protoxide of azote. The experiment must have been very often repeated since, though 1 am not aware that any very precise trials have been made to determine the change of bulk which takes place. It may be worth while, therefore, to relate here the result of a very careful experiment which I made to determine this point. Fifteen cubic inches of nitrous gas (containing one per cent. of azotic gas) were let up into a glass jar standing over mercury, and previously filled with that liquid. The barometer stood at 29-08 Vaz. XV. N° II. BP 226 Scientific Intelligence. [Marcn, inches, and the thermometer at 54°. Had the barometer stood at 30 inches, and the thermometer at 60°, the bulk of the gas would have been 14°72 cubic inches. Or (abstracting the azotic gas) 14:5728 cubie inches, | let up into this gas 50 grains of clean iron wire, together with a little water, just sufficient to moisten theiron. ‘he iron began slowly to rust, and the nitrous gas-to diminish in bulk. But as the experiment was made in winter, when the cold was severe, the diminution went on but slowly. After the interval of a month, it seemed to have reached its maximum. I allowed it to remain a fortnight longer, however, and then measured the residual gas. It amounted to nine cubic inches, the barometer standing at 29°94 inches, and the thermometer at 42°. This would have been 9°317 cubic inches if the barometer had stood at 50 inches, and the thermo- meter at 60°; or, abstracting the azote, 9-1698 cubic inches. This residual gas was pure protoxide of azote; for, being left standing upon water for 24 hours, it was totally absorbed by that liquid, except the 0-1472 cubic inch of azotic gas with which the nitrous gas had been originally contaminated. Now this residual gas, instead of one half, amounts to very near two-thirds of the residual gas. I ask, how this is to be explained? It is true that in other experiments (made im warm weather) I have seen the bulk of the nitrous gas reduced almost exactly to one half of its original bulk ; but the experiment above related was made with rigid attention to accuracy. Is it not probable from this that the specific gravity of the gaseous residue is not always the same? The subject obviously requires further elucidation. The common opinion entertained respecting the. way in which the oxygen is abstracted from the nitrous gas in this experiment is this. The iron decomposes the water in contact with it, unit- ing with its oxygen, and setting free the hydrogen. Thenascent hydrogen acts upon the nitrous gas, abstracting half the oxygen, and thus converting it into protoxide of azote. Austin and -Davy, and probably other chemists, have shown, that a little ammonia is evolved during this process. Now there is one thing that makes me hesitate about adopting this explanation, ‘simple as it is, as the true one. After the bulk of the gas has decreased so as to reach its maximum, I have never observed any increase to take place ; yet if the process had consisted in the decomposition of water by the iron, that decomposition ought to go on as long as any water continues in contact with the iron; and after the nitrous gas has been converted into protoxide of azote, the hydrogen, as it does not decompose the protoxide of azote, ought to mix with it, and increase its volume. But I have never found any hydrogen gas mixed with the protoxide of azote im this experiment; and what appears still more conclusive, if possible, 1 have placed iron wire in contact with a httle water m a glass vessel over mercury, and allowed it to remain beside 1820.] Scientific Intelligence. 227 another jar, in which the nitrous gas was converted into protox- ade of azote by moist iron, yet the iron wire yielded no air bubbles during the whole time the process lasted. Il. Phosphorous Acid. Berzelius has endeavoured to prove, in a paper which he pub- lished some years ago, that the oxygen in phosphorous acid is to that in phosphoric acid as the number 3 to 5. The composition of the two acids, according to his view of the subject, is as follows : Phosphorous acid composed of, .. 2 phosphorus + 1°5 oxygen Phosphoric acid. ............0 2 + 25 so that, in order to obtain whole numbers for oxygen, we must make the weight of an atom of phosphorus 4, and consider phosphorous acid as a compound of one atom phosphorus and three atoms oxygen, and phosphoric acid as a compound of one atom phosphorus and five atoms oxygen. A set of experiments which I published some years ago seem to me to demonstrate the. constitution of these two acids ina satisfactory manner. Phosphuretted hydrogen gas is of the specific gravity 0°9022. It is composed by weight of Phosphorus. 025 6 12 or 1°500 Tydrogen, ...... Pics ae 1 0:125 ‘Therefore, if it he a compound of an atom of phosphorus and an atom of hydrogen, an atom of phosphorus must weigh 1:5. This gas for complete combustion requires either its own volume of oxygen gas, or 11.time its own volume. Now this gas consists of one volume of hydrogen gas combined with one volume of the vapour of phosphorus, and both condensed into one yolume-; therefore the hydrogen in this gas will require half a volume of oxygen gas to convert it into water; so that the phosphorus in a volume of phosphuretted hydrogen gas is capable of combining either with half a volume of oxygen gas, or with a whole volume. In the first place, phosphorous acid is formed, and in the second place phosphoric acid. By these experiments (which were made with the utmost care) it is demonstrated, I conceive, that phos- phoric acid contains just twice as much oxygen as phosphorous acid combined with the same weight of phosphorus. These experiments are much more decisive than those of Berzelius, and they have the advantage of being much more easily made. All that is necessary is to procure phosphuretted hydrogen gas in a ‘state of purity. The specific gravity of phosphuretted hydrogen gas being 0°9022, and hydrogen gas _ not altering its bulk when it Is con- verted into phosphuretted hydrogen gas, it is obvious that if we subtract the specific gravity of hydrogen gas from that of phos- P2 228 Scientific Intelligence. [Marcu, phuretted hydrogen gas, the remainder will be the weight of phosphorus existing in a volume of phosphuretted hydrogen gas. Specific gravity of phosph. hydrogen 0-9022 Specific gravity of hydrogen. ...... 0:0694 Phosphorus. 0. ciate ies dias ~. = ():8328 This number 0°8328 may be considered as the specific gravity of a volume of phosphorus in the state of vapour. We have then phosphorous acid composed of 1 volume vapour of phosphorus .. = 0°8328 . + volume of oxygen gas. ........ = 0°5555 But 8328 : 5555 :: 1-5: l-very nearly. Hence it follows, that if an atom of phosphorus weighs 1-5, phosphorous acid is a com- pound of one atom phosphorus + one atom oxygen; and that the weignt of an integrant particle of it is 2°5. Phosphoric acid is composed of 1 volume vapour of phosphorus. .. = 0°8328 1 volume oxygen gas. .......0- =pldii But 8328 : 11111 :: 1:5 : 2 very nearly. Therefore phosphoric acid is a compound of one atom phosphorus = 1°5 and two atoms oxygen = 2; and the weight of an integrant particle of it is 3°5. There exists but little difference of opinion between Berzelius and myself respecting the composition of phosphoric acid. The ‘ numbers resulting from my experiments are, Phosphorus. .acdsalsitepe Sie Wal visita obo. Sne 100 Osy gen seis bet igiti ston s wana Sapa ob 1334 While the numbers of Berzelius are, Phosphorus ..... EGE ciel oh Rie wheter LOOMS Oxygen ies ves Peewee seeeee is aca is Now my numbers are corroborated by the direct experiments. of Sir Humphry Davy, who found that 100 phosphorus, when bummed in a high temperature, absorbed 135 of oxygen. The mean of the experiments of Berzelius and Davy gives us the following numbers for the constituents of phosphoric acid : Phosplioras Spy PI P50 Poa oe aS 100-00 Dayenn. erates sees oe. 13158 These facts seem to me to lead us without any hesitation to. admit phosphoric acid to be a compound of 1 atom phosphorus = 1°5 + 2 atoms oxygen = 2. It is with respect to the composition of phosphorous acid that 1820.] Scientific Intelligence. 229 the principal difference of opinion exists. I consider it as com- posed of :' PROspRorus, -. . an<'esiate.a yam, osha 4 aca ee ee ae rrr os Berzelius, as composed of PVG SB OROS iis, Serhaie aie slain sea cw cate OOO OR BeBe oe ian ot cei siti absl ey nhes stale .. 74:94 Berzelius ascertained the composition of phosphorous acid in the following manner: He dissolved 2:211 parts of protochloride of phosphorus in water. Now it is known that when this com- pound comes in contact with water, its two constituents are converted respectively into muriatic acid and phosphorous acid at the expense of a portion of the water, the chlorine uniting with the hydrogen of that liquid; while the phosphorus unites with its oxygen. He threw down the muriatic acid by means of nitrate of silver. The fused chloride of silver weighed 6-915. Now the chlorine in this portion of chloride of silver amounts to 1:705. This weight of chlorine to become muriatic acid must- combine with 0-0474 hydrogen. This hydrogen it acquired by the decomposition of water, and this hydrogen must have been in combination with eight times its weight of oxygen, or 0°3792, which must be the quantity of oxygen that combined with the phosphorus in 2:21] parts of protochloride of phosphorus. But the phosphorus in the chloride was 2:211 — 1:705 = 0:506; so that, according to this experiment, phosphorous acid -is com- posed of PPRDSPMOTUS, 602.0 ogo a. rs 506°0 or 100-00 OE cre ato ain 50 che = soe Ole (oe But the consequences deduced from this experiment depend upon assumptions which have not yet been demonstrated. If the protochloride of phosphorus, have the property of absorbing more chlorine than an atom, which seems to be the case, if the analysis of it by Davy be nearly accurate, then the whole conclu- sions deduced by Berzelius from the experiment, as far as the constitution of phosphorous acid goes, fall to the ground. Now Davy found protochloride of phosphorus a compound of “E RORBMOT US. | caps 2t arneck ¥/s > «2798 GEL DUO Chiormeis cde «cee At ee 10°62 5:345 Here the proportion of chlorine is almost one-fifth greater than an atom. But let us consider protochloride of phosphorus as a compound of one atom chlorine and one atom phosphorus. Its constituents must then be: . Obigmine. ss. ceeded, . « Web athe Sper tcte Phosphorus ,. blartyetesel Cin 230 Scientific Intelligence. [Marcu, When it comes in contact with an integrant particle of water, the hydrogen of the'water combines with the chlorine, and the oxygen with the phosphorus, constituting muriatic acid and phosphorous acid. Now water is composed of Gryoian, a nate cies See eee 1-000 Hydrogen. ........% bela atm ruleetmces (Oo tee When an integrant particle of protochloride of phosphorus: comes in contact with an integrant particle of water, a double decomposition takes place, and there are formed 1, An integrant particle of muriatic acid composed of Otorme!.'.So55 2s: 22% ate SC pe 4-500 Ely aro sel cee ope eee 5 7 emg 0-125 2. An integrant particle of phosphorous acid composed of oa anniek kierenuieielln & 1-0 PROB DOT Se «ois nhnsct.conisiaiey> hae naaaels » 15 Thus it is not possible that phosphorous acid can be a com— pound of any thing else than 1 atom phosphorus. ........ = 1:5 or 100 J atOM ORYPED 0s ae sides c= rO 9 662 even from the very experiment upon which Berzelius has founded his opinion. I do not expect that the preceding train of reasoning will be viewed as satisfactory by Berzelius. His notions respecting the atomic theory are so different from mine, as are likewise his opinions respecting the composition of muriatic acid, that we differ entirely in the original data from which we respectively set out ; but I think they will be admitted to be perfectly satisfac- tory by every one who has imbibed accurate notions respecting the atomic theory, and who is acquainted with the present state of the science. ; Professor Berzelius will, I hope, forgive me for expressing my regret at the unfortunate opinions which he has adopted respect- ing the laws to which chemical combinations are subjected. These opinions have been the result of an almost infinite number of experiments, conducted with the most minute attention to precision ; and they have been deduced with exquisite address as the final results of these experiments. No person can have a greater admiration for the talents and industry of this illustrious chemist than I myself have ; and no one is more fully sensible of the numerous obligations under which chemistry lies to his _ sagacity and unrivalled analytical skill; yet I have not the smallest doubt that the fundamental opinions by which all his conclusions are regulated are inconsistent with the true chemical Jaws of nature 1820.) Sezentific Intelligence. 231 Ill. Meteorological Table. Evtracted from the Register kept at Kinfauns Castle, N. Britain. Lat. 56° 23’ 30”. Above the Level of the Sea 129 feet. Morning, 8 pidlockaliyeke 10 o'clock. | cma Depth |No, of days, emp. F 1819. Mean height of | Mean height of - Pal Rain -—_—_ |—————_—_ | Six’s : or |Fair Barom. Ther, Barom, | Tuer. | Ther. |In. 100] Snow. Jam s....2.,.| 29'4T6 37°29) 29-472 37839 38-839 4°20 18 | 13 Reb: ss o4 29:418 | 36-071 | 29-442 | 36-571147 785| 9-45] 14 | 14 March .... .| -29°720 41°226 29°737 | 41°161/42°580) -1°10 9 | 22 fT ae 29-722 44500 29'T04 | 45°530/45 656} 4°50 12 18 Misy A, <2. 29855, 50-350 | 29-852 | 47-420|51-129} 1-15 | 12 | 19 SEMIRES ies jmove. o's 29°728 54:466 29°713 | 51-400/55°433| 2°35 bie 13 “Ut alanis 29°895 58613 29°S96 | 56-549}60-064! 1-20 7 24 PARYEON ota a!aiaoic'= 29°852 60-419 29°886 | 59-387/63-129) 1-40 Ge 125 SEheseives -- - 29°7166 52°466 29°7140 52-100 53 866| 1:70 10 20 RCE ct ota a) i0i <2 29°728 44°806 29°754 | 44°419'46-677| 4°20 14 17 NiGiiee aincie sci) 20 O40 35°309 29 670 35°700 36°700 1-89 ll 19 BAPE Sieln wine <2) 29-613 32-774 29°608 | 32°130)33°451| 2-55 13 18 Aver, of year.| 29-701 45°69) 29°706 | 44°85047-109! 28-60 | 143 jge¢ ANNUAL RESULTS, MORNING. BaRromeErer, TAERMOMETER . Observations, Wind. : Wind. PAPHOS EISEN: elias, WY 5. SOA | SUIY BE oe ok cast WW, sca WOne Lge, Ur Sl tires ES PETE Dee EL ee NEW Le EVENING. Highest,‘Sept. 20... NW .... 30°40] Awe. 17... soi... ee | Om 1 bd Lowest, Jan. 17 .... NW .... 28°79 | Decs 10 ...,0dece0s0eee- NW.... 17° Weather. Days, Wind. Times. MOAT oid os ole bak, patho arararaye vos ern IN eA IED pda ote talt oe 28 Rain or Snow ......50.e ee eae 148 Band) 8 Ry ih .cch- nace: GaN 10 MATS WN, so aha anihlte «claps ki 60 365 WY andl, NEN > ciecaxe Saisie) peicaieras 168 365 Extreme Cold and Heat, by Six’s Thermometer. Colitest, DecemberT1— Wind W..,. ...0.00 oc cac crm cas cccs 11° Hottest, August 17, Wind F.......5.......6.. Rhaneedictsye 6 nye 80 Mean temperature for 1819.................- bode oop niceip'e SIL 09R Result of three Rain Gauges. . dn. No, 1. Ou a conical detached hill above the level of the sea 600 feet.... 22°36 No. 2. Centre of the garden, 20 feet... ... Mie Niaie snip siti eave gov vid aie ean gp TE No.3. Kinfauns Castle, 129 feet ....., Neg cme « we sees ohedvcdreees TORO Mean of the three gauges,..... COP gewrrecesaaaaesr ee Oe reer eee eee 27°05 232 Screntifie Intelligence. [Marcu, V. An Account of the State of the Barometer, Thermometer, and Wind, during the late Hurricane, at the Island chi Thomas’s, an the West Indies, as observed on Board H.M.S. Salisbury. Communicated by Col. Beaufoy, F.R.S. 1819. Time. Barom. | Ther, Wind. Remarks, -Sept.20) 8&8 P.M. 29°97 NbyE 2) 8 A.M. 29°85 N Noon. 29-77 In 35! 29-72 82° 1 36 £972 NW by N BITS 29°70 2. Va5 29°10 ol £9°6T PATS) 29°65 ie ZO 29°55 8 35 29-50 9 20 29-40 9 55 29°40 WNW | 16 30 29-30 | il oO 29°95 | Il 45 29:15 22) 8 30 28°80 SW 4 15 29:95 Sris 29°50 12 30 29°75 Height of the hurri- | A 00 29°75 70 cane with thunder 7 20 29°72 and lightning. V. Method of determining the Specific Gravity of Gases. In the first volume of the Memoirs of the Wernerian Natural History Society of Edinburgh, the members of that Society did me the honour to insert a paper of mine on olefiant and carbu- retted hydrogen gases. In that paper I have given an account of the method which I have long been in the habit of following for taking the specific gravity of gases. [have reason to believe that this method has been generally followed in Great Britain ever since I made it known. But if we are to judge from the account which Biot gives of the mode of taking the speeifie gravity of gases in his Traité de Physique, and from the deserip- tion which Berzelius gives of his own experiments to determine the specific gravity of sulphurous acid gas,* it does not appear to me that the chemists on the coritinent are aware of the faci- lity with which the specific gravity of gases may be taken. My method is foundedona well-known fact that when twogases are mixed their bulk does not alter, I have a large glass flask fitted with a stop-cock. I weigh this flask as accurately as possible ; then exhaust it, and weigh it again. The loss of weight sus- tained is equal to the quantity of common air drawn out, and is less or more according to the size of the flask and the goodness of the exhaustion. Let itbe =a. 1 then fill the flask with the gas whose specific gravity [ want, taking care to exhaust the # See the last number of the Annals of Philosophy, 1820.] Scientific Intelligence. 233 stop-cocks connected with the apparatus before the gas is let in All the precaution necessary is to take care that no particles of water or mercury (supposing the gas to be standing over mercury) insinuate themselves into the flask. It is obvious that the volume of gas which will enter the flask will be precisely equal to the volume of common air that has been previously drawn out of it by the air-pump. I now weigh the flask thus filled with the gas whose specific gravity I wish to know. The increase of weight of the flask above its weigut when exhausted gives exactly the weight of the gas introduced into the flask, Let this weight be = 6. We have now obtained the weight 6 of a certain unknown volume of gas, and the weight a of exactly the same volume of common air. Now I say that the specific gravity of the gas is = ~. Or we have only to divide the weight of the gas 6 by the weight of the air a. This quotientis the true specific gravity of the gas without any correction whatever being requisite either for temperature, or for the height of the barometer; because all gaseous bodies undergo the same change of volume by the same application of heat or pressure. Hence the specific gravity of air bears the same ratio to that of the gases at every temperature, and under every pressure. Had Berzelius employed this method, he would not have required three days to obtain a very imperfect approximation to the specific gravity of sulphurous acid. Whoever will take the specific gravity of this gas in the way that I have directed above will find it just double the specific gravity of oxygen gas ; or 2:2222. It very seldom happens that the gas whose specific gravity is taken is perfectly free from some admixture of common air. In such cases it is always necessary to determine the volume of air in the gas, and when this is known, the specific gravity of the pure gas may be deduced from that of the mixture by a very simple calculation. “Let x = specific gravity of the pure gas, A = the volume of air in the mixture, a = specific gravity of air; B = volume of pure gas present, c = specific gravity of the mixed gas, then _ (A+B)e—Aa a, = VI. Combinations of. Prussic Acid. My facetious correspondent, who subscribes himself ‘“ Jack Addle,” would have spared. his animadversions on Count Le Maistre’s paper, if he had recollected that mistaken inferences in science, when the mistake is obvious, and has been pointed out even before it has been committed, can never be in the least injurious to the progress of science ; while a haughty rejection ot the first attempts at experiment, even though these attempts 234 Scientific Intelligence. [Marcn, should not be very successful, may damp the ardour of some person to whom hereafter the science may lie under obligations. Chemistry was nearly losing the unrivalled abilities and industry of Scheele by a piece of carelessness, for I will not call it haugh- tiness, of Bergman. Scheele, a young man whom nobody knew, sent a paper to Bergman, then in the height of his repu- tation, purporting to be a mode of obtaining tartaric acid in a state of purity from tartar. Bergman threw aside the paper without looking at it. Scheele of course was provoked. He withdrew his paper, and sentit to Retzius, who was a Professor at Lund. Had Retzius treated the paper in the same way that Bergman did, Scheele’s name miglit never have been heard of. But fortunately for the science of chemistry, and for the reputa- tion of Sweden, Retzius sent the paper to the Stockholm Academy, by whom it was published. That Count Le Maistre’s supposed new prussiates are mere mixtures of prussiate of iron with the different earths, &c. which he employs cannot escape the notice of any one who is acquainted with the action of acids on yellow prussiate of potash. One hundred grains of this salt, when treated with sulphuric acid, deposit 33 grains of pure prussiate of iron. Mumiatic acid will probably occasion the same deposit. It is this portion of prus- siate of iron thus evolved that occasions the blue colour in all the Count’s experiments. But what then? Is it not possible that some of the mixtures which he points out may be useful as pig- ments? Or may not his views lead to the discovery of some useful pigment ? These were my motives for mserting the paper in question in the Annals of Philosophy, and they seem to me to be perfectly legitimate. My readers would judge very erroneously if they were to conclude that I adopt or admit all the views given in the different papers published in the Annals of Philosophy. The authors alone are responsible for the opinions which they give. If a paper possesses ingenuity, plausibility, or novelty, andif itmay have a tendency to excite others to useful researches, I never hesitate to insert it, though it should be contrary to all _ my own preconceived opinions.—1. a Ui Geographical Position of Modena. In the year 1808 Baron von Zach made a set of observations to determine the latitudeand longitude of the Lower Guirlandina, in Modena. He obtained the following results :. DatiadeiNee ccc, ee Stee . 44° 38’ 55:9” Longitude E. from erme. 2; 3 . Bes 28 34. 59-2 He found the position of the Lower Asinelli as follows : Tatra Ni ic Sess ox ps » ay OE Longitude, .nsppsactiewreip or serra GO. 0 9-2 1820.] Scientific Intelligence. 235 It is curious that the position of this city, one of the chief towns in Italy, the seat of a sovereign prince, of an Italian society, of several celebrated astronomers, and a well-known astronomical instrument maker, was never determined till a German astronomer took the trouble to determine the point as late as the year 1808.— (Correspondence Astronomique,i.p.403.) VIIL. Cadmium. Dr. Clarke, Professor of Mineralogy at Cambridge, has disco- vered cadmium in the radiated blende of Derbyshire. | This discovery has been confirmed by several chemists in London, who have detected it likewise in other ores of zinc. A detailed account of Dr. Clarke’s experiments will be given in a future number. IX. On fattening Pigs. By Mr. J. Murray. It is stated in an English paper that a pig belonging to Mr. Fisher, of Scrooby Inn, gained, by feeding on Jndzan corn, in * the course of sir weeks and three days, the enormous weight of Sifteen stone. The pigs in the vicinity of Naples are so fat as to be able to move only with difficulty ; and I was curious to learn in what manner this desideratum was obtained. I was informed that the pigs were always fed in the first instance with Indian corn, and then generally permitted to shift for themselves. The method adopted by the Neapolitans to ascertain when the animal is ripe for the knife, is as extraordinary as it is cruel. An iron probe is plunged into the side of the animal, and when the point touches the muscular fibre, it is indicated by the expression of pain. The above fact is here corroborated, and the agriculturist may advantageously avail himself of the discovery. X. Varnish for Wood. By Mr. J. Murray. In vol. xi. pp. 119 and 371 of the Annals of Philosophy, Mr. Gill has afforded some excellent remarks on the French varnish for cabinet work, &c. The cabinet work at Rome seemed to me truly beautiful. I was informed by the workmen that in order to produce the effect, olive oil was first used, and a solution of gum arabic in boiling alcohol afterwards applied to the surface. 236 Col. Beaufoy’s Magnetical [Marcu ARTICLE X. Magnetical and Meteorological Observations. By Col. Beaufoy, F.RS. Bushey Heath, near Stanmore. Latitude 51° 87! 44-27” North, Longitude West in time 1’ 20°93”. Magnetical Observations, 1820. — Variation West. — Morning Observ. Noon Observ. Evening Observ. Month. : Hour. | Variation. | Hour. | Variation. | Hoar. | Variation. Jan. 1] 8b 45'| 24° 35’ 32” 1" 35’| 24° 37! 194g 2| 8 45/24 33 55/ 1 30/24 38 20 z 3] 8 50| 24 33 57| 1 30| 24 36 17 = 4| 8 45] 24 34 34] 1 25| 24 87 08 5 5| 8 45|24 33 36] 1 15/24 38 O4} & 6| 8 45| 24 36 14] 1 15/24 39 26 3 | ee! eee eS cme we 8| 8 45| 24 41°30] 1 15} 24 40 37 5 9| 5 45/24 36 O1| 1 30|24 39 48} § 10} 8 45} 24 34 32] 1 30] 24 38 08 3 41] 8 45| 24 34 40| 1 30/24 38 49 4 12|.8 45|24 34 33] 1 35] 24 38 39 2 13] 8 45/24 32 59| 1 30] 24 37 Og = 14] 8 45| 24 33 06| 1 15| 24 35-56 Ss 45} 3 50| 24 83 07 | 1 15/24 36 2 PF 16] 8 50|24 32 30] I 25|24 43 21 Jj] 8 50/24 30 58| 1 30|24 36 O1 > 18} 8 50| 24 34 10] t 20/24 38 14] 3 19] &§ 50/24 85 38] 1 25|24 39 10] 28 20} 8 50| 24 34 O7 | 1 15|24 37 42 8 21} 8 45| 24 34 22] 1 35|24 35 56 3 22} & 50|24 35 59/| 1 25/24 39 384 2 23) 8 50/24 38 30] I 20/24 37 56 5 24] .8 50°] 24 84, 4) | — — | — — — = Silicone da eal teas 24 39 06 =| 26) 8 50/24 32 45] 1 20/24 37 13 “ 27|" ‘8° 50 | 24" Si 36)" N25: |.94 3718 = 28} 8 50/24 34 21] 1 30|24 36 13 e 291 8 50/24 86 O1] ‘1 25 | 24 37 34 be SO)! oa) a ee | a ok Sz 59 = 31} 8 50|]2t 33 16] 1 30] 24 38 18 | S —— | ‘Mean for } . ca ha 48/94 34 06| 1 26] 24 37 7 ~ In taking the mean, the morniug observation of the 8th and the noon observation of the 16th are omitted, being unu- sually great, for which there was no apparent cause. 1820.] and Meteorological Observations. 237 Meteorological Observations. Month. | Time. | Barom. | Ther.}| Hyg. | Wind, |Velocity.|Weather,] Six’s, aaa SS a ila ae Jan. Inches, Feet. Morn....} 28°948 220 69° NNE Clear 21° 1 Noon,...| 28°972 2T TT WNW : Foggy 278 Even....{ — ~~ = = = = Morn....| 29°121 | 24 | 71 | SbyW Cloudy t 225 2 |Noon....| 29:070 | 34 | 83 SSW Rain 35 Even....) — == == = = 9 Morn....| 29:100 | 29 | 83 NW Snow ‘ 29 sf Noon,...| 29°311 | 30 | 65 || NW Clear 30 Even....)| — _ aS = — Morn....| 29-600 | 24 | 82 | WSW Fine ' aa 4 Noon....| 29°579 30 ve Var, Fine 30 Even....| — _ —_— SS —_ Morn....| 29673 | 21 | 80 | Wsw Very fine t =n a Noon,...| 29680 28 81 SSW Very fine} 31 Even....| — = = — _ Morn....| 29°635 | 30 | 83 | WNW Fibe ‘ 24 cf Noon....| 29°635 37 Th NNW Fine 31 Even....) — = == = _ Morn.... _ — _— — — ‘ 30 a Noon,...| 29°828 | 31 64 E Very fine} 312 Even....) — = = == — Morn....| 30°053 | 25 | 73 NE Sn. show. ‘ = a Noon,...| 30°053 Q7 65 ENE Cloudy 21% Even....) — _ _ = — Morn,...| 30°205 | 22 | 81 NE Sn. show. ‘ 19 9< |Noon....} 30°205 28 63 NE Fine 293 Even....) — _— — — as Morn....| 29936 | 19 | 90 | NNE Fine t ay 104 |Noon....| 29-900 | 25 | 68 NNE Snow 262 Even....| — _— _ == — = Morn....| 29:485 | 25 | 85 SSW Sleet ‘ 23 nf Noon,...| 29°288 | 30 80 Wbys Fog, snow 32% Even....| — —_— — aS = Morn....| 29500 | 25 | 78 E Cloudy |$ 2 wf Noon....| 29°600 23 12 ENE Sno 24g Even....| — _ — a pass Morn....| 29654 | 17 | 79 | NNW Fine , 16 132 |Noon....| 29-630 | 26 | 170 N Snow 26 Even....)| — _ _ = we Morn,...| 29°719 | 22° | 71 ENE Snow t 163 142 \Noon....| 29°688 25 65 ENE Snow 25 Even....) — _ _ er — , \Morn....| 29°343 | 13 | 74 NNW Cleat ‘ ir 15¢ |Noon,...| 29°243 | 19 68 WwW Very fine} 28 Even....) — _ _ s = Morn....| 29-200 | 22 | 91 NNW Pleas ‘ 18% 164 |Noon,...| 29-237 28 69 WNW Clear 282 Even ...) — — _ = — 99 Morn....| 29174 | 28 | 90 SW : nf Noon....| 29100 | 33 | 85 | SSW Been 333 Even....) — — _— — am Morn....| 28-905 | 27 | 84 | ENE Snow ‘ = is} Noon....}| 28:883 29 83 ENE Snow 45 Even....) — _- _ — wu SO ne) . ->5. ee eee lUL- BelearS, & « . s sinsicisig 2 20 pi w.s(devaslarge DUG 1 a ee ZOD nfaere 5 Ba Ai es ATH se iin a0 1a) te lcs ee ain are, altel eee Lag, 5 eis ig. pi Sb wax olga 2°895 June. ssh 2 pe ae oS SL Aiore,« onstacete 2-502 Sly cists orate is.+ - SRE AS LE i aE Aes at! 1 | (UTS a er ene of Sone re see 3°665 september. ...2.... £21. .s0... 3-281 RIGEONED ston \sin oss as) Re Oop ees 3°922 November ...... a4jaej 0 OU) ike sin ped SOU BICCEADEE 6. Oe ono. nt O29, 0s elvncapa Doe Mota reise Pitan a, 408 36-140 Whether we consider the averages as deduced from Mr. Walker’s observations, or from my own, or from the two united, the conclusion is equally obvious; namely, that the first six mionths of the year must be considered as dry months, and the last six months of the year as wet months; also, that Apml is the driest month in the year, and that the sixth after, or October, is the wettest, or that in which the most rain falls, in a long continued series of years, in the immediate neighbourhood of Manchester. It would be interesting to inquire how far these conclusions apply to Great Britain in general, or to Europe at large, or still more generally to the northern temperate zone. Tn the 4th vol. of the Society’s Memoirs, p. 576, is given an abstract or summary of Mr. Hutchinson’s account of rain at Liverpool for 18 successive years ; namely, from 1775 to 1792 inclusive. The annual average is 344 inches. Every one of the first six months yielded less rain (on the average) than any one of the last six months of the year. March was the driest, and October the wettest month in the year. In the same volume, p. 580, there are given the results of 16 years’ observations of the rain at Dumfries, by Mr. Copland, namely, from 1777 to 1793. The annual average was 37 inches, The driest month is April, and next to it March ; the wettest is September, and next to it October; and each of the first six months of the year is drier than any one of the last six. At Chatsworth, Derbyshire, from the same volume, p. 586, et seg. 1 deduce the following averages for 16 years (1777 to 1792 inclusive), as per table. Here again we see that March is the driest, October the 256 Mr. Dalton on Meteorology. [Aprit, wettest, and all the former six months drier than any one of the latter. By combining the 10 years’ observations of Dr. Campbell, of Lancaster (Memoirs, iv. p. 264 and 591), we obtain similar results nearly. March is the driest, and August the wettest month at. Lancaster. But 10 years is too. short a period to obtain true means. [I have the rain at Lancaster for a subsequent period of 10 years (1802—1811), furnished me by my friend John Ford, jun. Esq. of Ellel; which likewise gives March for the driest, but October for the wettest month of the year. In the Annales de Chimie et de Physique (vol. vii. 1818), there is an account of rain at Viviers, lat. 44° 29’ N. long. 2° 2’ E. of Paris, by M. Flaugerges. The monthly means for 40 years’ observations (from 1777 to 1818) are stated, from which it appears that February is the driest month in the year, and October the wettest. The annual average is 34 inches (French). The year 1801 was the wettest in that period, yielding 48 inches (French), and 1779 was the driest, yielding 20 inches 7 lines. Viviers, which is in the 8.E. of France, has, however, some essential differences from Great Britain in regard torain. There the months of July and August are among the driest ; the only months distinguished for heavy rain are September, October, and November; while April and May yield each more than the monthly average. I have collected the Royal Society’s account of rain at Lon- don for 28 years, ending in 1806, and find the averages to stand as under; also those of Luke Howard, Esq. for a subsequent period of 12 years, ending with 1818, made in the vicinity of London. These united are as per table. The fall of rain at Kendal for five years (1788—1792) was ieee in my Meteorology ; since that time the account has een continued by my brother for 18 years, with which he has favoured me ; I have obtained also two years further from good authority, making in all 25 years’ ram. The monthly averages I have deduced as per table. I deduced the average rain at Paris from observations published in the Journal de Physique for the last 15 years, as er table. e The average rain at Glasgow for 17 years (1801—1818) was deduced from a paper in the Annals of Philosophy, vol. xii. p- 377. 1820.] Mr. Dalton on Meteorology. 257 Mean Monthly and Annual Quantities of Rain at various Places, being the Averages for many Years. e 5 =e ane SA 5 : , . ° . 2 = n _— — a "mH MH, wn a we nm u ~~ = ~ i - bal = — - te 2s | sa |on |e -a/ 35] e258 - a S008 itis 2 oo ae Pa) a) a: = oO ae so oc ae x= o7 7 nm SP} srl ern th aoe I cm mu = 2p a) ico =O 2:9 Eo Wt WO SOE | So ae iss) uo a an OR s— = ow = — ae = 4 io) = 3 a iG) a) om > o Inch. | Inch. | Inch. | Inch. | Inch. | Inch. | Inch. | Inch. | Fr. In.|Fr. tn.) Each. Jan. ....) 2°510) 2°177| 2°196) 3°461| 5-299] 3°095! 1°595] 1-464) 1-228 Feb. ....| 2°568| 1:847| 1-652] 2-995] 5:126} 2-837] 1:741} 1-250) 1-232) 1 700] 2-295 March...) 2:09S| 1:523| 1°322] 1-753} 3°151] 2-164] 1°184| 1-172} 1-190! 1-927] 1-748 April....] 2-010} 2°104| 2-078} 2-180} 2°986} 2°017| 0°979| 1°279} 1-185) 2-686] 1-950 May ....| 2°895} 2-573; 2-118! 2-460; 3-480} 2°568| 1°641} 1°636| 1°767| 2931} 2-407 June ...4| 2°502| 2°816| 2-286} 2-512) 2°722] 2:974) 1°343] 1-738! 1-697) 2-562] 2-S15 July ....| 3°697| 3-663) 3°CO6| 4°140) 4°959| 3:256| 2303] 2°448) 1-800] 1-882! 3-Fk5 Aug. ....| 3°665) 3:°311| 2°435| 4°581| 5:039] 3°199| 2-746] 1°807} 1:900| 2°347} 3-bos Sept.....| 3°281| 3°654| 2-289] 3°751| 4-874] 4-350) 1-617} 1°842} 1°550| 4-140} 3-135 Weta... 3-922] 3°724| 3:079| 4:151| 5439] 4-143].2°297; 2°092| 1-780) 4-741! 3-537 Nov.....| 3360) 3°441 | 2°634) 3°775) 4-785] 3°174} 1-904 2°222 | 1°720| 4°187| 3-180 Dec. ....| 3°832|] 3-288] 2°569| 3-955) 6-084] 3-142] 1:°981] 1°736) 1°600) 2°97] 3-05s ————— | | fl 6 fee, Observations on the Theory of Rain. Every one must have noticed an obvious connexion between heat and the vapour in the atmosphere. Heat promotes evapo- ration, and contributes to retain the vapour when in the atmo—~ sphere, and cold precipitates or condenses the vapour. But. these facts do not explain the phenomenon of rain, which is ax frequently attended with an increase as with a diminution of the temperature of the atmosphere. The late Dr. Hutton, of Edinburgh, was, I conceive, the first ,. person who published a correct notion of the cause of ram. (See Edin. Trans. vol. i. and ii. and Hutton’s Dissertations, Ke.) Without deciding whether vapour be simply expanded by heag, and diffused through the atmosphere, or chemically combined with it, he maintained from the phenomena that the quantity of vapour capable of entering into the air increases in a greater ratio than the temperature; and hence he fairly infers, that. whenever two volumes of air of different temperatures are mixect together, each being previously saturated with vapour, a preci- pitation of a portion of vapour must ensue, in consequence of the mean temperature not being able to support the mean quan— tity of vapour. This explanation may be well illustrated by contemplating a curve, convex towards its axis, in which case the ordinates increase in a greater ratio than the abscissw. The abscissa represent temperature, and the ordinates the quantity of steam which the corresponding temperatures are capable of retaining, In 1793 1 published my Meteorological Observations and Vou, XY, -Ne iv; R 258 Mr. Dalton on Meteorology. [Aprit, Essays, a few years after this theory of rain had been made known ; as far as I was then acquainted with it from one of the Reviews, it appeared the most plausible of any I had seen; but on looking at my remarks, it is evident I had not been made acquainted with its distinguishing feature, and that on which its excellence depends ; namely, a higher solvent power (if it may be so called) in the air, than what is proportionate to the increase of temperature ; and that the precipitation of vapour in the form of clouds and rain is occasioned not by mere cold, but a mixture of comparatively warm and cold air. At the time of my publication of the Essay on Rain, &c. I had a strong bias to the opinion, that the steam or vapour in the atmosphere exists in a state of combination with heat, but with- _ out any chemical union with the elements of the atmosphere ; only it is subject to be wafted along mechanically by the great body of the atmosphere in its ordinary currents. This opmion was founded and supported on the authority of the late M. Saus- sure in:part ; he having determined by direct experiment that a cubic foot of dry air of the temperature of 66° would imbibe 12 grains of water for its saturation. Now, from experiments on the boiling of water in vacuo, | was persuaded that this quantity of vapour was nearly what would fill a cubic foot of empty space, in the temperature of 66°; and, by analogy, I concluded that the quantity of steam necessary to saturate any given volume of air at any temperature was the same that would be requisite to fill an equal void space at the same temperature. This reasoning was of course hypothetical at that time, and unsupported by any direct experiment. In 1801 a series of essays of mine were read before the Society, and subsequently published in the fifth volume of Memoirs; one object of experimental inquiry was, whether steam of any kind was the same in quantity in air and in a vacuum, all other circumstances being the same. The result was decidedly for the affirmative. Another object was to ascertain the true force of steam im all atmospheric temperatures. This was clearly proved to be pro- gressively increasing with the temperature, as Dr. Hutton had rightly conjectured. Indeed with a slight modification of the thermometrical scale, the temperature is an arithmetical progres- sion, and the force of steam a geometrical one. Hence the curve showing the force of steam is what mathematicians call the logarithmic, one remarkably convex to its axis. The cause of rain, therefore, is now, | consider, no longer an object of doubt. If two masses of air of unequal temperatures, by the ordinary: currents of the winds, are intermixed, when saturated with vapour, a precipitation ensues. Ifthe masses are under saturation, then less precipitation takes place, or none at all, according to the degree. Also the warmer the air, the greater is the quantity of vapour precipitated in like eircum- 1820.] | Mr. Dalton on Meteorology. 259 stances, as is evident to any one, on inspecting the logarithmic curve, or on considering that the increments of a geometrical progression, are in proportion to the terms. Hence the reason why rains are heavier in summer than winter, and in warm coun- tries than in cold. We may now inquire into the cause why less rain falls in the first six months of the year than in the last six months. The whole quantity of water in the atmosphere in January is usually about three inches, as appears from the dew point, which is then about 32°. Now the force of vapour at that temperature is 0-2 of an inch of mercury, which is equal to 2°8 or three inches of water. The dew point in July is usually about 58° or 59°, cor- responding to 0°5 of an inch of mercury, which is equal to seven inches of water; the difference is four inches of water, which the atmosphere then contains more than in the former month. Hence, supposing the usual intermixture of currents of air in both the intervening periods to be the same, the rain ought to be four inches less in the former period of the year than the average, and four inches more in the latter period, making a difference of eight inches between the two periods, which nearly accords with the preceding observations. In the preceding estimations of the whole quantity of water in the incumbent atmosphere of any place, I take for granted. that an atmosphere of steam is blended with the general atmo- sphere throughout, in the same vertical column, and subject to the common law of rarefaction in ascending. ‘This is a view of the aqueous atmosphere, which no one seems to have enter- tained but myself. I have been making experiments almost annually on the subject since 1802, on the mountains in the north of England, and particularly on Helvellyn. These experi- ments have been materially facilitated of late years by masses of snow, which have been found nearthe summit, in the month of July ; but it has often happened that the cold springs of water near the summit have been adequate. By one or other of these, the dew-point of the air may be found at any required elevation on the mountain, and the law by which it is regulated in the ascent may be investigated. On some future eceasion, | intend to draw up a memoir on this subject. In the mean time I may observe, that all the phenomena concur in exhibiting the same variation of density in the aqueous vapour atmosphere in its present mixed state, as would no doubt be observed in an atmosphere of pure steam of equal density. 260 Dr. Reade s Experiments for [Aprit, Artic.E III. - Experiments for a new Theory of Vision. By Dr. Joseph Reade. (To Dr. Thomson.) SIR, Cork, Dec, 1, 1819. Kadasora ici. Ken. PrERHAPs no subject in natural philosophy has more engaged the attention of the learned, nor claimed more interest, than that concerning the proper seat of vision. For 200 years the retinal theory has been maintained, and its difficulties, ifnot absurdities, softened down by the learned ingenuity of mathematicians and metaphysicians, well aware that to overturn a theory so univer- sally adopted, and stamped with the seal of antiquity, requires a number of well regulated experiments and legitimate deductions, { now commit my endeavours to the candour of the intelligent reader. Lxperiment 1.—Having often remarked, when examining the eyes of patients, that surrounding objects, such as a lighted candle, &c. were painted on the transparent cornea in a beauti- ful and minute manner, as on the face of a convex speculum, it occurred to me that the mind might receive impressions or ideas from those erect images ; and 1 was the more desirous of bringing this interesting suggestion to the test of experiment in consequence of the many difficulties attached to the present system of vision. I now pasted two narrow strips of black cloth in the shape of the letter T, and about three inches in length, on one of the upper panes of a large and well lighted window. I then requested a gentleman with a large pupil and good sight to seat himself about four or five feet from the letter, and to fix his eyes steadily on it. Looking into his pupil I perceived the letter T to be minutely yet distinctly painted by reflection. I then took a plano-convex lens in my right hand, such as school boys use for burning glasses, and held it close to the pupil. On again looking at the corneal image of the letter T, I perceived it enlarged, or magnified, in all its dimensions, and the spectator said he also perceived it much larger than with the naked eye. On removing the lens a little further from his eye, I perceived the letter on the pupil not only magnified, but surrounded with colours, and the spectator saw the letter large, confused, and surrounded with colours. So far the phenomena of vision answered exactly to the changes of this corneal image. I next removed the lens somewhat further from the eye; and on looking into it perceived the letter T to be inverted, and the spectator likewise saw it inverted. He now took the lens in his own hand, and placing it at different distances before his eye, 1 was enabled, by means of 1820.] a new Theory of Vision. 261 the corneal image, to tell him what he saw. Having again requested the spectator to fix his eye on the letter, I placed a double concave lens before the pupil, and the letter was immediately diminished ; he now said he'saw it very small. Here I shal! beg leave to remark that these experiments strike at the very first principles as laid down for optical instruments. For we find by two simple and conclusive experiments, that a convex lens, instead of converging the rays, as first maintained by Maurolycus in his treatise “ De Lumine et Umbra,” actually and bona fide diverges and magniffes the image in all its dimen- sions; and, on the other hand, that a concave glass converges or diminishes the image. The object of this paper being merely to draw the attention of the scientific to my opinions on optics, and particularly on vision, I shall not at present enter more fully into the theory of spectacles, &c. Paietinent 2.—Having placed a plano-convex lens at such a distance before the spectator’s eye, as to form an inverted image of the letter T on his pupil, I placed a double concave lens behind to represent an opera glass, or gallilean telescope. The inverted corneal image immediately became erect, and the spec- tator said he also saw it erect. . Experiment 3.—The above experiments were made at ‘about four feet from the window; [ now requested the spectator to remove his chair to within a foot of the object, and on placing a convex lens immediately before the eye, the corneal image was considerably magnified : on slowly removing the lens nearer the letter, and further from the eye, the black corneal image began to be surrounded with colours, but did not become inverted, nor did the spectator perceive any change of position: when close to the object, the corneal image appeared better defined and more distinct. I now placed a prism before his eye, and desired him to look through the lower refracting angle; as he was unaccus- tomed to the application of this instrument, he could not regulate it so as to perceive the coloured image of the letter T. I, there- fore, turned the prism until I perceived it on the pupil, and then told him exactly what he saw, making a mirror of his eye. Let us now inquire what changes the intervention of a plano-convex, or a concave glass, would make on the letter T brought to a focus on the retina by means of the crystalline and other humours. Having removed the fat and coats from the back part of an ox’s eye, as performed by Kepler and Scheiner, and thus laid bare the retina, { placed a lighted candle in front. An inverted image was seen as if floating on the retina. I now placed a plano- convex lens between the candle and the cornea at such a dis- tance as to form an inverted image on the pupil. The retinal image remained inverted. On now placing a double concave lens at a little distance before the convex one, the corneal and inverted image became erect, while the retinal inverted image - 262 Dr. Reade’s Experiments for [Arrit, was not in the least changed as to position. Here is a direct experimental proof that even if an mverted image were painted on the retina, that inverted image, not undergoing any change of position by the intervention of the glasses, could not be the image conveyed to the mind. To suppose for one moment that an inverted image on the retina could produce both the idea of inversion and erection would be adding another inconsistency to Kepler’s catalogue. In this experiment the changes of the corneal image were accompanied by simultaneous changes in the mind; therefore, that, and that alone, must have produced the sensations. On placing a glass globe about two inches dia- meter, filled with water, opposite the letter T, and then inter- posing a convex lens, the posterior invertedimage wes obliterated ; the rays of black light not being sufficiently strong, the same thing took place with a concave lens. Dr. Priestley, who wrote a number of metaphysical works, gravely informs his readers “ that the want of an inverted image might produce the sensa- tion of an erect one.” With the highest respect for the Doctor’s opinions, we might just as readily believe that the want of a man’s dinner would get him a supper! There is no inverted Image ever painted on the Retina.— Having removed the fat and -coats from the back part of an ox’s eye, and thus bared the retina in imitation of Kepler’s and Scheiner’s experiments, I placed a lighted candle on a table in front; and on looking through the retina, my eyes being placed beyond the principal focus of the sphere (or rather two segments of one), I certainly did perceive a beautiful inverted image of the candle, as if floating on the retina. So far the experiment seemed to accord with the retinal theory of vision; for if the rays were refracted and converged, as represented by optical writers, by means of the cornea, aqueous humour, crystalline lens, and vitreous humour, they should cross nearly in the centre of the eye, and finally paint an inverted image on the retina. However, on approaching my eye nearer to the retina, I per- ceived the inverted image to become large; confused, and when my eye was very close, it opened into two curved and inverted images, which receded laterally ; and at a yet nearer approach, formed into a circle, through the centre of which I perceived a very distinct and erect image of the candle, evidently coming from the anterior surface of the eye, and perfectly distinct from the inverted one, considerably magnified in passing through the humours. Kepler, in placing his eye beyond the focus of the ox’s eye, which is nothing more than a simple sphere, saw an inverted image, formed by the junction of the two images painted on his own cornea, which he mistook for one on the retina, asa person looking into a concave mirror thinks that he sees an myerted image in the glass. Here I think it necessary to give arough sketch of the passage of the ranys through the eye, 1820.] a new Theory of Vision. : 963 articulatly as my opinions are diametrically opposite to those of all optical writers. A glass globe filled with water, and about two inches dia- eae : meter, may serve those unacquainted; ——, ‘aienain with morbid dissections. 4 b, ‘two — oid rays of light coming from the upper i ea and lower parts of the candle, impinge on the transparent cornea at c, and paint an erect image. This image again transmits rays, diverging as they pass through the sphere to g, where the spectator sees @ magnified and erect image. ‘The ifhage at the cornea ¢ also sends rays forming inverted images, in consequence of the rays crossing at d and e. These images take the curvature of the globe, and uniting mto one inverted image, form what has been denominated the principal refracted focus at f. Now itis evident that Kepler, to have made his experiments correctly, should have placed his eye at g, and not at Te Indeed his eye should almost touch the retina; and then, as I have already said, he would have seen an erect magnified image of the candle, and not an inverted one, surrounded by what optical writers denominate a circle of aber- ration. [tis really surprising how any person could for a moment believe that this circle of aberration could produce vision. “According to the present theory of vision, long-sightedness they say 1s produced by the image being formed beyond the retina, short-sightedness by an image formed before the retina’ in the vitreous humour—both physical impossibilities. The rays of light are supposed to be converged in the body of the eye. 1 would beg leave to put the following question : Would the crystalline lens when imbedded in the vitreous humour act in the same man- ner as it would in air? Certainly not, as the following easy experiment may show. Take a large basin of water, hold a powerful glass lens in such a position over the water as to form an inverted image on the side of the basin and under the water, then immerse the entire lens, and at no distance can a focus be ever formed, the circular shadow with its black circumference is perceived, but nothing else. Now surely the refractive power of glass, in proportion to that of water, is much greater than that of the crystalline lens in proportion to that of the vitreous humour. Mr. Harris, im his pick, p- 95, says, “It is very difficult, I think, to determine accurately the measures of these refractions ; but, from such experiments as could be made, it has been found that the refractive powers of the aqueous and vitreous humours are each of them much the same with that of common water, and that of the crystalline is a little greater : that is, the proportion between the sines of incidence and refrac- tion out of air into the cornea, or aqueous humour, is as 4 to 3, out of the aqueous humour into the crystalline as 13 to 12; and out of the crystalline humour into the vitreous as 12 to 13.” From analogy we are authorised to conclude, that the crystalline 264 Dr. Reade’s Experiments for [Aprit, Yens can never form inverted images on the retina, and that the lens is placed in the centre of the eye to magnify or diverge the rays, and not to invert the object. Moreover, that the crystal- line lens does not produce inverted images on the retinais shown by what takes place when removed by the cperation of depres- sion or extraction. Forif the lens were so essentially necessary to vision, its removal must cause blindness. In answer it has been said, that after the operation, the patient is obliged to use convex glasses, or spectacles, to supply the place of the lens. From many years’ practice in these complaints,i.am enabled to say, that this is by no means the case. In young patients, the use of convex glasses, although at first of assistance, is ultimately unnecessary, if not injurious, foras the eye gains strength, they are enabled to see all objects at a limited distance fully as well as those labouring under short-sightedness. Some time since | removed a congenital cataract from the mght eye of Mary Skil- lington, aged 19. After the operation she never wore a glass, and can now see to thread a needle ; she also sees perfectly well at different distances to the extent of 200 feet and upwards. Miss Jenkins, of Bantry, writes and reads perfectly well, and attends to the business of her shop without the use of spectacles. This Lady came to Cork to consult a London quack, who pro- fessed to cure all diseases of the eye that were curable: luckily for this patient she did not come under the denomination. Indeed. after the operation in young subjects, I never recommend the use of a convex glass. In those patients wanting the crystalline Jens, the rays cannot come to a focus on the retina; yet had Kepler and Scheiner removed the lens from the ox’s eye, as I have repeatedly done, they would have found that it made not the slightest difference in the inverted image, which they con- ceived to float on the retina. Neither could the crystalline jump backwards and forwards to accommodate the eye to the object at different distances. Indeed I cannot conceive the cause of this jumping of the lens. If the distance of the object be ascer- tained, and consequently the object seen before the lens, with its thousands and tens of thousands of muscles, begins to jump, what occasionis there for that movement? But ifthe jump take place before the object be seen, then the extent of the jump can- not be ascertained. Look before you leap should be a maxim with all metaphysical jumpers. The fact is, that the eye princi- pally judges of different distances by comparing the visible size of the corneal image with the educated sense of the tangible object, intervening objects, strength of colouring, &c. On view- ing a painting, the objects are all equidistant on the canvass ; yei we conceive them to be at relative distances. The Supreme eing, with an invisible hand, paints the images of external “objects on the corneal canvass, and the mind conceives them to be at relative distances on the same principle. The following easy experiments may also show that the rays diverge in passing 1820.) a new Theory of Vision. 265 through a sphere, or convex glass. Take a cylindrical tumbler, fill it with clear water, and holditin the left hand opposite a window. Hold a black slate pencil, or any other slender body, about three inches in length behind this glass vessel; when close, one magni- fied image is seen, but on gently withdrawing the pencil to a greater distance, this image becomes more magnified, and at a certain distance, two images, fully as well defined, are seen at each side of the tumbler; on continuing to withdraw the pencil two everted images are seen to glide with a considerable degree of curvature towards the posterior surface of the tumbler and at last coalesce into one image, which obliterates the anterior one, or that formed at the anterior surface. This corre- borates the inferences drawn from the former experiment. When the object is near the posterior surface of the tumbler, the eye receives the rays considerably diverged or magnified ; when the object is at some distance from the posterior surface, the eye receives the rays from the coalesced image formed from the two lateral images. From this experiment there can be no doubt whatsoever that the eye receives rays from two distinct and separate images; and also that the mind receives impressions from a glass globe or convex lens in nearly a similar manner. Should a doubt yet remain, the following experiment may be made: Place a red wafer under one of the planes of a triangular glass prism, resting on a sheet of white paper; we immediately see two everted images of the wafer formed in each lateral plane, as thus represented A as . The wafer a sends rays or images to band c. As the prism has plane sides, the two images can never come to a focus at any distance ; but if we round off the angle, they immediately unite, and form an oblong image of the wafer, as thus represented (YQ: From these experiments, and many others hereafter to be related, in the second volume of the Experimental Outlines, not a doubt remained on my mind that reflected erect, and not inverted images, gave mental impressions of a visible world. Surely if any thing can increase our admiration of the power and wisdom of a Supreme Being, it is the conviction that a beautiful and ever yarying landscape is painted in miniature on the trans- parent cornea. When we consider that the black choroid shines through the retina, we should admit that it is very unfit to be the reflecting mirror of the mind. To bring this to the test of experiment, [ turned out the aqueous, vitreous, and crystalline humour of the eye of an ox; on bringing the inverted image of the black letter T pasted on the window to float on the retina, by means of a convex lens, I found that it was perfectly invisible; in some places confused ; indistinct in all. Indeed the retina, were it free from this and many other objections, and also free from 4 266 Dr. Reade’s Experiments for [ApRiL, the large blood-vessels and nerve running over its surface, from its being ofa grey colour, like pounded glass or animal jelly, would be very unfit, and could never form an image of a grey object per- fectly similar to itself, neither could objects the colour of the ‘choroid coat ever be seen. We might as well think of writing with black ink on a sheet of black paper, as attempt the forma- tion of dark images on a dark ground... On the other hand, how adiirably fitted both for reflection and transmission is the cornea, both sufficiently transparent and sufficiently opaque; no coloured substance could answer the purpose. It has hitherto been the received opinion, that the two optic axes, concurring at the object, make an angle, according to the size of which the cbject appears large or small; but this opinion, whose inconsistency has been already pointed out by Bishop Berkeley, must yield to the more rational theory, that the mind takes the apparent mag- nitude and distance from the size of the corneal image, and not from lines and angles beyond the nervous influence, or from invisible rays, all rays being invisible, which are transparent until intercepted and reflected. ‘In vain (says Berkeley) shall all the mathematicians in the world tell me that I perceive certain lines and angles which introduce into my mind the various ideas of distance, so long as I myself am conscious of no such thing.” Indeed we might as well believe in ghosts and hobgoblins as believe that we could see an object, or the image of an object beyond the nerves ; thatis, beyond the transparent cornea. Here is the rubicon, the utmost limit beyond which the mind can never travel. Surrounding objects are brought to the eye by means of the rays of light: hence the nerves convey them to the sensorium. Indeed the idea that the mind could travel beyond the cornea, ride on the whirlwind, and, like a fairy mab, measure invisible angles of an invisible and distant image, is so very inconsistent that we cannot but express surprise at its adoption. If a man were gravely to say that he could touch the moon, he would be looked on as mad ; but an astronomer says, that on looking through a telescope he can measure the invisible image of that body nearer to the eye than the moon, and beyond the influence of the nerves ; and the astronomer gets credit for the assertion. As the knowledge of distance almost entirely arises from experience, founded on the analogy between the sense of sight and touch, the former ata very early period of existence 1s inadequate to regulate our perceptions. When an infant begms to notice, natural education commences, external objects are the letters, and the nerves the instructors of the mind. The insufficiency of sight is evident by the anxious desire to feel and to examine every new plaything. The image of the rattle is delineated on the cornea, and the child believing it to touch the eye, grasps at it although far removed. On the same principle I have heard a child cry bitterly for the moon to play with, In a few months, the sense of touch has partly educated the eye in judging dis- 1820.] a new Theory of Vision. 267 tance by the apparent magnitude of the corneal image. A man born blind and suddenly restored to sight would suppose every object to touch his eye. All that is accomplished by telescopes and microscopes (according to the retinal theory) is first to make an image ofa distant object by means of a lens, and then to give the eye some assistance for viewing that image as near as possible; So that the angle which it shall subtend at the eye may be very large, compared with the angle which the object itself would sub- tend in the same situation ; this is done by means of an eye-glass which so refracts the pencils of rays that they may afterwards be brought to their several foci by the natural humours of the eye. Now it is evident from the foregoing experiments that this theory is perfectly erroneous, and that a telescope, as shall here- after be more fully shown, does nothing more than diverge the rays, or magnify the image on the cornea. In the gallilean telescope, the convex lens magnifies the erect image which it forms on the concave eye-glass, the use of which, by regulating the sphere of concavity, is to obviate the colours produced by the sphere of convexity. Hence an achromatic and magnified corneal image is formed. I shall here notice a difficulty which Dr. Barrow and all other opticians have failed to clear up, parti- ceularly noticed by the Bishop of Cloyne. ‘ Let an object be placed beyond the focus of a convex lens, and if the eye be close to the lens, it will appear confused, but very near to its true place. If the eye be a little withdrawn, the confusion will increase, and the object will seem tocome nearer; and when the eye is very near the focus, the confusion will be exceedingly great, and the object will seem to be close to the eye. But in this experiment the eye receives no rays but those that are con- verging; and the point from which they issue is so far from bemg nearer than the object, that it is beyond it; notwithstanding which the object is conceived to be much nearer than it is, though no very distinct idea can be formed of its precise dis- tance.” Here Dr. Barrow supposed that when his eye was close to the lens it received none but converging rays; whereas, on the contrary, they were diverging; and as he withdrew his eye, the more the erect image was magnified, when magnified beyond the standard of distinct vision it became confused. But when the eye was beyond the focus, the anterior or erect image was lost to the eye, and the two lateral and inverted images coalesc- ing into one, formed an image which was nearer the eye floating as if on the posterior surface of the lens. Dr. Barrow, like a true philosopher, acknowledges himself unable to account for this appearance, finishing his lecture with this observation: “ Vobis itaque nodum hunc, utinam feliciore conatu, resolvendum committo.”” Whether these experiments tend to untying the knot, I leave the reader to determine, and shall not enter on Berkeley’s or Barrow’s theories of apparent distance in this paper. 268 Dr. Reade’s Experiments for (Apri, We next come to the rectification of inverted images on the retina. This, according to Scheiner snd Kepler, is the business of the mind, which, when it perceives an impression on the lower part of the retina, considers it as made by rays proceeding from the higher parts of the object tracing the rays back to the pupil where they cross one another. But this hypothesis (says br. Priestley, a great metaphysician) will hardly be deemed satisfac- tory; and, by way of clearing up the difficulty, he proceeds thus: “ Upper and lower are only relative terms; and as all objects are painted upon the retina in a similar manner (all the upper parts in one direction, and all the lower parts in the other), it is by custom only, founded on experience and the association of ideas, that we learn to distinguish them from one another, so as to direct our eyes, or point our hands upwards or downwards, as we have occasion. [If this be the true solution (continues the learned Doctor) it will follow that if the images of objects had always been painted in a different manner, that is, erect as the objects themselves are, we should have acted as we do now without being sensible of the difference, a different association of ideas only having taken place.” Now all this laboured expla- nation comes to nothing more or less than that we are taught by experience. However, we never find the infant or the brute {incapable of these refined associations) mistaking the top for the botttom, or the right for the left. When the world was turned upside down by philosophers, they should have attributed the circumstance to blind instinct, and not to reason. For indeed reason has nothing whatever to do with the business. In the summer of 1812, | performed the operation for cataract on a very intelligent boy, named Edward Carey, aged 10 years; he was born with such opaque cataracts as merely to enable him to distinguish light from darkness, or the shadow of an interposed hand, but was incapable of distinguishing the outlines of an object, or the most brilliant colours. After the operation, an before he could acquire any ideas from association, having inquired the manner in which he saw, he answered that he saw objects as he felt them, supposing them to be very near the eyes. Although Cheseldon was an advocate for the retina being the seat ofsyision, he does not make any particular observations on this difficulty, but says that the young gentleman whom he couched with congenital cataracts “‘ knew not the shape of any object, nor any thing from another, however different in shape or magnitude; but upon being told what things were, whose form he before knew from feeling, he would carefully observe, that he might know them again.” When shown his father’s picture and told what it was, he acknowledged a likeness, but did not mistake the head for the feet. Indeed were there no other difficulty in the retinal theory of vision, the inversion of objects, or turning the world upside down, and making confusion of right and left, 1820.] a new Theory of Vision. 269 would be sufficient to invalidate the entire. The next difficulty in this catalogue of difficulties is the power of seeing objects distinctly at different distances. It is allowed on all hands that to see an object at different distances, either the retina or the crystalline lens must approach so as to shorten what is called the optic axis ; so that the crystalline, according to this theory, must be a great jumper. To calculate the number of jumps, or miniature leaps, the lens of a general officer would take at a review, might puzzle an algebraist, vulgar arithmetic being per- fectly inadequate to the solution. And then an able philosopher has given thousands and tens of thousands of muscles, or wings, if you please to call them so, to this little busy, fluttering thing. Indeed Dr. Young might as well have given muscles to an onion, the lamine of which, and those of the crystalline, being very similar. On examining all the different theories, we find them all differmg, and perfectly inadequate to the effect. Kepler, tyyo centuries ago, supposed that the contraction of the ciliary processes draws the sides of the eye towards the crystalline, b which means the eye is lengthened, and the retina pushed to a greater distance from the pupils when we are viewing near objects. Mr. Thomas Young differs from Kepler, Descartes from Young, Haller from Young, with a crowd of others whose opinions I think it unnecessary to mention. I remain, Sir, your obedient servant, Josepn Reape, M.D. P.S. The Editor’s observations would be acceptable. Articie IV. Reply to Mr. Holt on Rain-Gauges. By Mr. Meikle. (To Dr. Thomson.) SIR, Berner’s-street, Feb, 23, 1820. In the Annals of Philosophy for October last, I gave a very concise but unobjectionable refutation of the mistaken idea which M. Flaugergues and others entertain about the true cause of the difference bpzerved in the quantities of water collected in rain-gauges placed at different heights. I then flattered myself that, by means of a simple diagram, 1 had brought down the subject to the level of the most superficial inquirer; and, there- fore, did not encumber your pages with a tiresome harangue about a thing so extremely simple and obvious to every one. Some persons, however, seem still to cherish a predilection for their favourite error ; and among these your learned correspond- ent Mr. Holt certainly holds no inferior place; since in your 270 Mr. Meikle’s Reply to Mr. Holt (APRIL, © - number for January he has favoured us with an article in which he not only shows clearly that he has entirely misunderstood my explanation, but that he, if possible, still labours under a delusion superior to that of M. Flaugergues himself; who. probably fell into that unaccountable mistake merely through haste, or from having his attention so much occupied with the many interesting services which he renders to science. The Wernerian Natural History Society and the Bibliotheque Universelle are both of high authority; but an error is still an error in these, as well as truth is truth, should it occur m a novel. Unfortunately, however, for your currespondent, and the cause he has so faithfully espoused, the position I advanced is inde- pendent of authorities or opinions, since it must stand or fall with some of the simplest truths of geometry. Indeed it is almost inconceivable how any one who is but slightly acquainted with elementary geometry should feel the least embarrassed on seeing clearly that the horizontal distance, or distance of the points, in which the drops pass through a plane parallel to the horizon, is absolutely independent of their inclination where the wind runs steadily and horizontally. This I formerly showed, and shall now endeavour to do so again a little differently. Let A C, B D, with the intermediate a age parallels, represent the paths of rain- LAAAATAN drops falling perpendicularly ; and let LLIGAA A E, B F, with the parallels between them, be the paths of the same drops when acted on by a steady wind blowing from B to A. Suppose A B and E D paral- lel to the horizon. Nowsince A C must be parallel to B D, and A Eto BF, we have EF = AB=CD. A gauge, therefore, of the width C D would exactly receive the same quantity of rain if placed at E F, let the inclination be what it may. Con- sequently the quantity of water received by a rain-gauge is totally independent of the general inclination of the rain. If F Gbe perpendicular to A E, it must no doubt be less than EF. But however short F G may become, all the drops still pass through it; since the parallels A E, B F, &c. are only so much the more crowded together. The grand principle, there- fore, of M. Flaugergues’s mistake is his always proceeding on the supposition that the shortest or perpendicular distance of the Imes in which the rain falls is constant; whereas that varies with the sine of inclination; while it is the distance of the points in which the drops pass through a horizontal plane that is inva- riable. Mr. Holt has duly adopted the same mistake, only try- ing to improve upon it, by saying that the quantity of rain received will be proportional to the ang/e of inclination ; whereas M. Flaugergues makes it as the sive of that angle. As the rain drops, if first acted on by the wind, and afterward 1820.) on Rain-vauges. 271 gradually sheltered from it in approaching the ground, must obviously descend in curves; let H I, KL, UD with the curves between them, represent the WZ paths of the falling drops. Then since it is evident these curves must all be every way equal and similarly situated with respect to the horizon, it follows, that any line H K parallel to the horizon must be exactly equal any other parallel IL; so that the general obliquity of descent was no concern whatever with the quantity of rain which the gauge receives. “ Should the rain,” says Mr. Holt, “ be blown in a direction parallel to the horizon, it is obvious none could enter.” He might easily have added abundance of other remarks equally true, but like that altogether foreign to the poimt in question. Since it is not difficult to show that no wind running parallel to the horizon can ever carry rain drops also parallel to the horizon, until the velocity of that wind become infinite ; and when that takes place, your correspondent would do well to look out for the nearest place of shelter. From what I have shown above, we may venture to conclude that there is very little reason for constructing a particular sort of gauge to counteract a source of error which does not exist. Indeed admitting the opinion of these learned gentlemen to have been correct, the quantity of rain which falls on any given space of ground during wind would be less than what came away from the same area of cloud. Query—Is the rest annihilated, or what becomes of it that it does not reach the earth ? I formerly stated as my opinion that the paradox in question was some way owing to the obstruction which the gauge itself offers to the wind. ‘This idea (the first of the kind I recollect to have met with) has so highly-pleased Mr. Holt, that he has con- descended to give it ina slightly different form, as if it were entirely new and his own. Until some unexceptionable method be discovered for esti- mating the error to which gauges in an exposed situation are liable, I do not conceive such gauges are entitled to any notice whatever ; and since that error must be affected with the size of the rain drops as well as with the velocity of the wind, I despair of ever seeing the matter put to rights. Butif Mr. Holt will be so good as consider the subject with a little more attention, I hope “ it will appear to him that he himself has taken the wrong view of it.” I Iam, Sir, your most obedient servant, Henry MEIKLE. 272 Dr. Clarke on Cadmium. [ApriL, ARTICLE V. Observations upon the Ores which contain CapmMiuM, and upon the Discovery of this Metal in the Derbyshire Sihcates and other Ores of Zinc. By Edward Daniel Clarke, L.L.D. Professor of Mineralogy in the University of Cambridge, Member of the Royal Academy of Sciences at Berlin, &c. &c. In a Letter to the Editor of the Annals of Philosophy. (To Dr. Thomson.) DEAR SIR, Cambridge, Feb. 18, 1820. In vol. xiv. of your Annals, p.269, you gave some new details respecting Cadmium from the “ Annalen der Physik,” by M. Stromeyer, which excited in my mind a very great desire to see the ores which are said to contain this curious metal. Some varieties of radiated blende from Przibram, in Bohemia, are described as containing two or three per cent. of cadmium. At a sale which took place soon afterwards in London, I procured specimens of the particular mineral thus alluded to, which were sold under the name of splendent fibrous blende from Przibram, pronounced Priizbram. I found afterwards that they had been brought to England by Mr. J. Sowerby, of Lisle-street, a dealer in minerals, from whom I afterwards obtained more of the same substance. Upon my return to Cambridge, I endeavoured to obtain Cadmium from this ore, and succeeded, not following exactly the process mentioned by M. Stromeyer, because I made use of murtatic acid, in the first place, as a solvent, instead of the sulphuric, as being easier of evaporation; and hoping, by 2 careful evaporation to dryness, to separate any lead that might be present, the crystals of muriate of lead not being soluble in distilled water. Before any thing further is stated, it may be proper to describe the ore itself. The splendent fibrous blende of Przibram, in its external appearance, is not unlike red hydrosul- phuret of antimony, but it is so highly splendent as to exhibit a lustre nearly metallic, especially after a fresh fracture. It exhi- bits shining fibres, as radii diverging from a common centre, imbedded in common massive blende, which also has something of a radiated structure, and is associated with an aggregation of eubic crystals of sulphuret of lead. The purer fibrous part of the mineral, divested of the massive blende and of the sulphuret of lead, was selected for experiment. Its specific gravity in distilled water, at a temperature equal to 55° of Fahrenheit, is exactly 4000. The Abbé Hatiy makes that’ of sulphuret of zine, or the commen blende, to be equal to 4,1665. (A.) Twenty-five grains of this mineral triturated in a porcelain mortar exhaled a strong smell of sulphuretted hydrogen simply 1820.] Dr. Clarke on Cadmium. 273 by fracture and friction. It filled the whole house. Placed in strong muriatic acid, and the acid boiled, a solution took place, but without any rapid or vehement action, sulphur- etted hydrogen being evolved as before. The solution was then evaporated to dryness, and distilled water being added, the whole of the muriates were taken up, no /ead being present for separation ; but there remained undissolved a small portion of glittering heavy white particles, which, when col- lected on a filter and dried, weighed nine-tenths of a grain. These particles being examined with a lens were as diaphanous as the most limpid rock crystal. They proved to be diapha- nous guartz in the arenaceous form: some of them had the rounded botryoidal appearance of Santilite ; others were angular and polygonal. (B.) The filtered liquor collected from (A.) yielded an orange or orpiment-colowred precipitate to sulphuretted hydrogen; also a white precipitate to hydrate of potass, which was redissolved by adding hydrate of ammonia. (C.) The same orange-coloured precipitate from (B.) bein redissolved in muriatic acid, and the acid evaporated and distilled water added, carbonate of ammonia was poured into the solution in excess, which, holding the zznc in solution, threw down a white precipitate ; and this changed ye/low in drying by the loss - of a portion of its carbonic acid. (D.) The precipitate from (C.) being redissolved in muriatic acid, and the excess of acid driven off, and distilled water added as before, yielded an orange-coloured precipitate to sulphuretted hydrogen, distinguishing it from zinc; also to phosphate of soda, instead of the crystalline flakes or scales which zinc exhibits, it yielded a white pulverulent powder, which was redissolved in liquid ammonia. It was, therefore, carbonate of cadmium. It was moreover insoluble in water. But in drying the muriate of cadmium, if too much heat be applied, the salt is decomposed, and the oxide with a beautiful orange colour separates in an insoluble form simply by adding water. A stick of zinc of a cylindrical form, being placed in the diluted muriate mentioned in (A.) became coated over with a precipitate which had a dendritic appearance. When examined with a lens, minute metallic scales of a leaden aspect were dis- cernible. Having collected this precipitate by zinc into a watch- glass, and washed it, and evaporated the supernatant fluid, the residue appeared, a brown-coloured substance, which powerfully attracted moisture. Having exposed it almost to a red heat, it yet deliquesced in the instant of its cooling. Scraping off some of this on platinum foil, and heating it with the blow-pipe, it sent off white fumes; then intumesced, and exhibited a dark- brown, slag-like, substance, which, by further exposure to heat, was converted into an vrange-coloured oxide; and this again by alternately applying the point of the blue or the yellow Vot. XV N°IV S 74 Dr. Clarke on Cadmium. [Aprit, flame, became, either a dark slag, or an orange-coloured oxide, until the whole was dissipated by increasing the temper- ature. The last globules of the dark slag among the orange- coloured oxide had a metallic appearance. When borax was added to the above, a fine amethyst colour appeared, while hot, which vanished when it became cold. To prove that this precipitate by zinc was really cadmium, I redissolved it in muriatic acid, and, after the usual process, su/phuretted hydrogen gave its beautiful orange-coloured precipitate, and hydrate of potass & white precipitate, as before; which became redissolved by adding liquid ammonia. { have been the more particular in detailing these experiments, because upon their accuracy mainly depends the validity of my subsequent remarks respecting the presence of Cadmium in other ores of zinc. Inthe course of them, I had made some observa- tions which led me to conclude that Cadmium is more remarkably characterized by a tendency to crystallization, than even anti- mony, or any other metallic body. When the murtate of cad- miun is Gissclved in a very considerable body of water, far below saturation, as it adheres to the sides of a glass vessel and becomes dry, it shoots out into transparent fibrous crystals, which radiate in a very beautiful manner. Many other solutions of the metal are moreover characterized by a tendency to crystalliza- tion. Having observed this, 1 began to suspect that a radiated structure in ores of zenc might, perhaps, be an indication of the presence of Cadmium in these ores; and accordingly I began the examination of a specimen of sz/icate of xinc, which | had brought from the same sale, and which had been described in the sale catalogue as electric calamine from Hreyberg. it exhibited biack diverging fibres, accompanied by an orange-coloured earth, and, perhaps, it may be the sort of black fibrous blende in which Stromeyer is said first to have discovered Cadmium. Having dissolved a part of this mineral in su/phuric acid, and evaporated the acid almost to dryness, a sufficient quantity of distilled water was added to enable the fluid to pass the filters without destroying them; and having collected the clear liquor, sulphuric acid was again added, that an excess of the acid might be present according to Stromeyer’s process. A stream of se- phuretied hydrogen gas was then sent through the solution, and immediately a most vivid orange-coloured precipitate began to fall, With this precipitate L repeated the experiments before- mentioned, of solution in muriatic acid, &c. Xe. and after the usual process obtained carbonate of cadmium, as before, having all the characters of that carbonate. } made several attempts to revive the metal, but with httle success. By heating the carbonate and expelling the acid, I obtained the oxide of cadmium, and by placing this m a glass tube containing Aydrogen gas, and making the tube red-hot, a brilliant white-looking metallic appearance became fixed upon 1820.] _ Dr. Clarke on Cadmium. 275 the inner surface of the glass ; but which may, perhaps, be due to lead contained in the glass itself. At another time, having thrown down with sulphuretted hydro- gen the sulphuret of cadmium, and observing that its fine orange colour was darkened by the presence of dead, I endeavoured to ascertain the quantity of /ead present by reviving it in a crucible with soda. in this manner | obtained globules of pure lead, which lad separated from other bronze-looking globules that were brittle, and these after solution, &c. in muriatic acid gave an orange-coloured precipitate to sulphuretted hydrogen, and a white precipitate to Aydrate of potass, which was redissolved in liquid ammonia. It is evident, therefore, that they contained Cadmium, and were, perhaps, alloyed with copper; but the heat necessary for melting copper would volatilize cadmium, if Stro- meyer’s observation be correct, as stated in p. 274, vol. xiv. of your Annals. Having now exhausted my materials, [ went to London to see if I could procure any more of the dark fibrous silicate of xine. At Mr. Mawe’s shop in the Strand, I was shown something of a similar nature, although not agreeing as to colour. This was the Derbyshire silicate of xinc, having a greenish colour, with a radiated structure, like wavedlite, and containing in cavities the reddish-brown, or orange-coloured earth before-mentioned. The specific gravity of the pure fibrous part equals 3°6767, but itis a very impure mineral, containing, as well as the preceding si/icate, both copper and tron, besides a considerable quantity of magnesian carbonate of lime and fluor spar, Myr. Mawe furnished me with several of these specimens, and our professors of chemistry and geology, Cumming and Sedgewick, have kindly added more. Inalk of them I have found Cadmeum:; and the quantity of this metal in the ore may be, perhaps, ascertained ; because 540 gr. of the mine- ral, by the process | have already described, yielded 3-2,ths of sulphuret of cadmium, allowing rather less than -$,ths of a grain per cent. I have sent the carbonate of cadmium and the sulphuret to you for examination ; and you have confirmed what [have said as to their real nature. ‘The truth of the foregoing observations respecting the presence of Cadmium in our English ores of zinc has also been since confirmed by Dr. Wollaston and by Mr. Children, who have examined the Derbyshire silicates whence 1 obtained the metal, and obtained Cadmium from them. Since making the foregoing observations, I began the exami- nation of séhanBoglich ores of xénc, and especially of an ochreous earthy-looking carbonate of xinc, from Addstone Moor, in Cum- berland. This ore is dug near the house of a dealer in minerals, of the name of J. Cowper, who resides in the town of Aldstone. After its solution in sulphuric acid, when a stream of sulphuretted hydrogen gas is sent through the solution, it assumes a vivid orange colour, and a precipitate is thrown. down, which has the s 2 1 276 Berzelius’s Experimentsto determine the Composition [APRIL, colour of rhubarb; but this precipitate, when boiled in highly concentrated muriatic acid, is not wholly soluble in that acid ; and when the excess of acid has been driven off, and distilled water added, no precipitate is afforded to carbonate of ammonia. Zinc throws down from it a dark precipitate, which has not the characters of Cadmium. Hence I conclude that it does not contain Cadmium; and that the orange-coloured precipitates afforded by sulphuretted hydrogen from the solutions of the ores of zinc are not of themselves indications of the presence of that metal, wanting the subsequent proof of its presence to which | have alluded ; and the further testimony from subsequent tests used in the examination of the carbonate ; as described in the foregoing experiments. I have the honour to be, dear Sir, &c. &c. E. D. CLarKxeE. ARTICLE VI. Experiments to determine the Composition of different inorganic Bodies which serve asa Basis to the Calculations relative to the Theory of Chemical Proportions. By J. Berzelius. (Continued from p. 98.) Barytes, Sulphate,and Muriate of Barytes. TEN grammes of pure muriate of barytes perfectly deprived of water were dissolved in water, and the solution was mixed with nitrate of silver as long as any precipitate fell. I obtained in one experiment 13°806, and in another, 13-808 grammes of fused muriate of silver. Muriate of barytes, therefore, is composed of Muriatic acid ...... 26°37 ...... 100-000 Barytes srs ilejeieies an TO'OO 40s cee SSA OD If we calculate from this experiment the composition of a bea we find that it must contain 10°45, per cent. of oxygen. en grammes of muriate of barytes decomposed by sulphuric acid yielded in one experiment 11-217, and in another 11-218 grammes of sulphate of barytes. Hence sulphate of barytes is composed of Sulphuric acid...... 34337 ...... 100°00 Barytes? ov..se hf GBB 110 )0' ei A OUEOT If we calculate the composition of barytes from these data, we find that it should contain 10-443 per cent. of oxygen. The results of these two experiments then only differ 000008, and may consequently be considered as very near the truth. 1820.] of different inorganic Bodies. . 277 Composition of the Acids of Phosphorus, of the Phosphates, and Phosphites. The greater number of what is contained in this article having been already published in the Annals of Philosophy, it will be necessary to mention merely some new experiments which the author has made on the phosphates of barytes and lime. He had observed that the neutral phosphate of lime deviated a little from the composition which ought to result from the general capacity of saturation of phosphoric acid. He discovered after- wards that this deviation was owing to the great tendency which phosphoric acid has to produce the same subphosphate which exists in the bones of animals, a greater or smaller quantity of which always mixes itself with the neutral phosphate, when we endeavour to procure this last. He found iikewise that phos- phate of barytes gives a subphosphate when treated with caustic ammonia, and that in this subphosphate, the acid is combined with 11 as much of base as in the neutral salt: that is to say, that the salt is composed of Phosphoric acid ...... 27°07 ...... 100°0 Barytes’ ves. ieee T2098 1d a, 2093 The different anomalous subsalts and supersalts which phos- phoric acid produces with barytes and lime, deserve the attention of chemists ; and that so much the more because hitherto they constitute the only examples of their kind. When the quantity of phosphoric acid is the same, the multi- ples of the two bases in their different combinations with the acid are as follows; beginning with the combination, which contains the least base : Barytes. Lime. PABROSBNALE 0.0 4:5,0\0 -cainye nena Bit tai « aeté ] Acid phosphate prepared with alcohol. It ...... Jt PCMES ALL GSD AEC a 5 sc 25°) 24° 38. 210 24 45 | 24 31 12 1 20 |} 24 38 24 25 45 | 24 31 32 1 25 | 24 38 O7 26 50 | 24 32 56 1 20/24 387 08 1 1 1 Owing to the shortness of the days, evening observations discontinued, In taking the mean, the morning observation on the 12th — is rejected, being unusually great, for which there was no appae-_ rent cause. 1820.] and Meteorological Observations. 317 Meteorological Observations. Month. | Time, | Barom. | Ther. } Hyg. | Wind. |Velocity.]Weather,] Six’s, Feb. Inches, Feet. Morn....| 29°518 369 85° SSE Fog 35° : oon, 29-447 42 64 s Very fine} 43 Even. — —_ _ — — 98 NMOra. . ... 29-350 31 80 EbyS Cloudy 2 2jNoon....| 29°350 35 68 | NEby E Cloudy 35 Even. _— — _ _— — 31 Morn. . 29-482 31 TT NW Cloudy 32 |Noon....| 29°498 34 70 |NWbyN Cloudy 34 Even. — _ —s _ _— 30 Morn.. 29-560 31 73 W by N Cloudy 42 |Noon.. 29°560 35 67 SSW Cloudy 36 FEven....) — == = — _ Morn....| 29-475 36 87 SSE Noon....| 29°451 40 87 SSW Even .... = — =r = af Rain : Morn,...| 29°343 40 87 SE by E 6 Noon....| 29°440 44 71 Ww Even....) — _— — |. — Morn....| 29°664 | 45 | 95 SSW Fogey |§ 39 a Noon...., 29°678 AY 89 SW Cloudy 49 Even. —— = == = Mari: 2! 29-659 43 91 SW Sm. rain 42 < Noon,... 29-675 44 89 SSW Cloudy 45 Even'....| — —|— ~ —~ Morn....| 29579 | 40 | 92 | Sby Ww Foggy |§ 40 94 |Noon ...| 29-480 | 50 | 68 ssw Very fine} 50 Even....) — — = i _— Morn....| 29:378 | 43 | 88 Ww Rain 40 104 !Noon....| 29°470 45 70 NW Fine 464 [Even se, — — — — _ 312 Morn....) 29°640 34 87 SW Hazy ES 114 |Noon....| 29°593 45 82 SSW Cloudy Ads Even...., — — _ _ 4 Morn....| 29-392 | 37 | 87 | NNW Foggy |§ 2 we} Noon....| 29°443 Al 83 ENE Rain 42 Even....| — = _ _ _— Morn....| 29573 | 38 | 83 SSE Cloudy |§ 37 is} Noon....| 29°550 | 40 75 W byS Cloudy 4. Even....| — _ _ — _ Morn....| 29°725 | 34 | 79 | NNE Cloudy {§ 25 144 |Noon....| 29:752 | 40 | 60 | NNW Very fine} 42 thc aoe) = _ _ —_ _ ‘Morn....| 29827 | 31 | 87 | ENE Fog 29 Noon....| 29°838 34 80 ENE Hazy - 34 Even....| — _ — — — Morn....| 29-783 | 24 | 84 | NE Foggy ‘ om Noon....| 29°735 | 34 | 75 SW Fine 348 Even....| — _ —_ —_ _ Morn....| 29:600 | 27 | 74 | ESE Clear ; o 174 |Noon....| 29°595 32 64 ESE Fine 32 uljEven....| — —_ — — i Morn....| 29590 | 26 | 73 | ENE Clear ‘ he 18 2 -.-| 29590 | 32 65 NE Cloudy 32% VEN cece — — = —~ _ 318 Time. Morn.... Noon.... Even.... Morn,... Noon... Even,... Morn... Noop.... Even... Morn.... | xeon: Even... Morn.... 1 Noon.... Even ... Morn.... i Noon.... Even.... Morn.... Noon.... Even.... Morn.... Noon.... Even.... Mom,... Noon... Even.... Moern.... ! Noon.... Even.... Morn.... Noon.... Even .... Barom. Inches. 29:°625 29°630 29-379 .| 29°363 29°357 29°358 29-344 .| 29°340 29°129 29-100 28-984 28°902 28°969 29-008 29-450 29°533 29°608 .| 29°600 29-528 29°469 29°382 29°316 Ther. 30° 33 Hyg.| Wind. 71° NE 70 NE 85 NW 80 Var, 85 S 74 NE 96 NE 90 EK 93 SSH 85 SSE so | WbyS 85 | WbyN 88 N 83 NE 86 | NEby E 70 | NEbyE (a | EhyN 64 ENE 16 NE 63 EbyN 10 WNW 64 Ww Col. Beaufoy’s Meteorological Observations. Feet, [ApRiL, Velocity.| Weather. |Six’s, Very fine Very fine Clear Very fine Cloudy 28 Cloudy 34 Snow ‘ aT Snow _ Fog 5 . Fog 34 Fog, rain ‘ 32 Foggy A5 Rain ‘ 38 Cloudy AT Cloudy ‘ 36 Rain 38 Snow ‘ a Showery| 39 Stormy ‘ 32 ray 332 Cloudy ‘ 213 Very fine} 36 40 Rain, by the pluviameter, between noon the Ist of February, and noon the Ist of March, 1:143 inch. Evaporation, during the same period, 0°765 inch. 1820.] Mr. Howard’s Meteorological Table. 319 ARTICLE XII. METEOROLOGICAL TABLE. BaromeETeRr,| THERMOMETER, Hygr. at gr. 1820. Wind. | Max.| Min. | Max. | Min. | Evap. |Rain.| 9 a.m. 2d Mo. Feb. 15 E|30°09|29°96| 45 22 96 2} E_ |30°05/29:95| 46 27 97 3.N E|30°08|30°05| 36 30 93 4S W/{30°15)29'08, 40 27 80 5S E}30:08|30°97}, 45 38 _ 92 6| Var. |30°20)29°97| 48 38 93 7| W_ 130 22)30°20) 51 38 99 ») 8S W/30°24)30°14) 47 35 88 9} S 130°14/29°95| 53 35 99 10} W_ {|30°20)30714| 50 29 _— 99 11}N W{30-14/29°97| 49 35 10 93 12) W_ {30°10|29°97| 43 38 05 95 13\S E|30°29|30°09| 46 27 75 14, N_ |30°39|30°29| 45 30 97 |\@ i5|N — E/30°42/30°07| 38 24 91 16|N W/{30°37|30°24| 38 18 73 17\N ——-E}30°24/30°21| 35 15 55 83 18IN —_-E/30°22/30°18) » 52 23 87 19N E)30°22/30:00; 36 23 93 20, Var. |30°00|29:99| 37 27 95 € 23'S E\29°72|29'58| 53 37 96 24'5 W|29'°58/29'49| 42 34 13| 97 25IN —B30°02\29°51| 41 33 os} 95 26\N _—_—E|30°21|30°02) 36 29 91 27|N. —s—- E\30°21/30°13) 38 26 71 28\N __—EJ30°13/30°01| 40 20 78 29'S W/|30:01\29'62| 42 24 35 | 02} 99 1© ee | $0'4.2'29'49| 53 15 0°90 1-011100—71 The observations in each line of the table apply to a period of twenty-four hours, beginning at 9 A, M. on the day indicated in the first column, A dash denotes, that the result is included in the next following observation. \ 320 Mr. Howard’s Meteorological Journal. [Arnit, 1820. REMARKS, Second Month.—1. Hoar frost: very fine day. 3—6, Cloudy. ‘%, 8. Fine, 9. Cirrocumulus: fine. 10. Foggy morning: drizzly. 11, 12. Cloudy: some rain. 13. Very fine morning. 14,15. Fine. 16. Hoar frost; misty: then fine, with Cirrocumulus. 17, 18. Hoar frosts: clear, a.m. 19. Overcast : some snow in the evening. 20. Ground covered with snow this morning from two to three inches in depth: it continued to snow, with very little intermission through the day. 21. Foggy morning, with thaw: about five inches of snow on the ground, 9224, Overcast. 25, Overcast: windy. 26, Bleak wind. 27. Fine, 98, 29. Hoar frost: fine, with Cirrocumulus, RESULTS, Winds: N, 1; NE, 9; NW,3; W,3; SW,5; S,1; SE,4; E,1l; Var.2. Barometer: Mean height For the month. ..........:.eccaccccccevcceccsses SU ODS-inches. For the lunar period, ending the 6th. ............- 30°005 For 15 days, ending the 3d (moon north) ........ 29°93T For 13 days, ending the 16th (moon south) ....... 30°166 Thermometer: Mean height For the month....... ‘chajaeiere aa ateitine oe ble astcldinie «che xO For the lunar period, ending as above ........ ... 32°766 For 29 days, the sun in Aquarius. .........++.5--- SO'15SS Hygrometer: Mean for the month . .....sseseeeserseereeereeeee OL Evaporation... .ccccccsccosecsecessesccecccsccecsecees Stidaciese ae eeonChS BEAU Se pia y 20 isla aeigidanine’ otejnclepisnembsicnaes sah cork es cele ves inieninl mamee Mean temperature at Tottenham .......ccecceeececeereecceccsess S0'B2T° Hygrometer at ditto........ssecececeerecesecaccsssecsereeceees BLP Feat dios. id. o.dlecah srs sip v emo aievs'siosie svepigancatethinmemdese’ LnCpeiie #,* The late winter may be considered as having ended with the deep snow on the 20th, followed by a thaw on the 2Ist, though the spring has been frosty at times since: this snow occurred just 60 days after the shortest day ; and the snow on the 2Ist of tenth month, 1819, was just 60 days before it: thus the winter may be said to have lasted 120 days, with some mild intervals, the solstice being in the midst of the time. = ERRATUM IN LAST MONTH. For Aquarius read Capricorn, Laboratory, Stratford, Third Month, 23, 1820, L. HOWARD. ee ANNALS oF PHILOSOPHY. MAY, 1820. ArTIcLE I. Biographical Account of Dr. James Bradley, F.R.S., Astro- nomer Royal. PERHAPS as an observer Dr. Bradley has never been surpassed by any astronomer whatever; while his two grand discoveries of the aberration of the fixed stars and of the nutation of the earth’s axis constitute a memorable era in astronomical science, and raise their author to the very highest rank among the culti- vators and promoters of that most sublime and useful science. I am desirous on that account to insert a short biographical sketch of his life in the Annals of Philosophy ; though 1 have nothing whatever to add to the account published in the 62d volume of the Histoire del’ Academie Royale des Sciences, from which all the lives of Dr. Bradley, which have appeared in different English publications, have been translated with greater or less accuracy. James Bradley was born at Sherborne, in Dorsetshire, in the ~ ear 1692, and was the third son of William and Jane Bradley. e received the early part of his education at North Leach, in a boarding school kept by Messrs. Egles and Brice, who are said to have used their best endeavours to cultivate the happy genius which they observed in their pupil. From this place he went to Oxford with the intention of studying theology, and of taking orders. As soon as he was of sufficient standing to take holy orders, the Bishop of Hereford, who had conceived a great esteem for him, gave him the living of Bridstow, and soon after he was inducted into that of Welfrie, in Pembrokeshire. But Wen. AV. Ne YY. xX 322 Biographical Account of [May, notwithstanding these advantages, which seemed to promise him the likelihood of advancing to still higher dignities in the church, he was induced at length to resign both his livings that he might be at full liberty to indulge his passion for mathematics and astronomy. The voice of nature is all powerful, and often destroys at once those arrangements in which she had not been sufficiently consulted. Mr. Bradley was the nephew of Mr. Pound, well known in the republic of letters for several excellent astronomical observations. Indeed he would probably have published a great deal more had not the journal of his travels been destroyed in the conflagration at Pulo-Condor. This conflagration accompanied the massacre made, by the inhabitants of the island of all the English in the place. Indeed Mr. Pound himself very narrowly escaped the fate which attended so many of his countrymen. It was with this relation that Mr. Bradley spent all the time which he could spare from his livings. He seems to have acquired by his own industry, without any other teacher, a sufficient knowledge of the mathematical sciences to relish and profit by the conversa- tion of his uncle. It is easy to conceive that the example and the conversation of his uncle did not render the official duties of Mr. Bradley more agreeable. He continued, however, to discharge them with assiduity, though he cast at times-a wishful eye upon the heavens, and began at that time to lay the foundation of those discoveries which have raised him to the ranks of the greatest astronomer of his time. Though these observations were made in some measure by stealth, the name of Bradley became famous enough to reach the ears of the most illustrious names in England. Lord Mac- clesfield, Sir Isaac Newton, Dr. Halley, and various other cele- brated members of the Royal Society, became known to him, and cultivated his friendship. It was the estimation in which he was held by these great men that led to his becoming a Fellow of the Royal Society. About this time, Dr. Keil, who filled the place of Savilian Professor of Astronomy at Oxford, died. It would have been difficult to have found so good a successor as Mr. Bradley, whether we consider his abilities or his fondness for astronomy. He was unanimously elected to the chair on October 31, 1721. Thus at the age of 22, he found himself the colleague of the celebrated Dr. Halley, who was at that time Savilian Professor of Geometry in the same university. Dr. Bradley, as soon as he was inducted into this chair, resigned both his livings in the church. He had long felt the disagreeable situation in which he was placed, his official duties as a clergyman, and his passion for astronomy drawing him contrary ways. And he took the first opportunity that offered to put an end to his constraint. He was now at liberty to indulge his passion for astronomy 1820.) Dr. James Bradley. 323 without interruption ; and in 1727 he enabled others to enjoy the fruit of his researches by publishing his theory of the aber- ration of the fixed stars, one of the most useful and ingenious discoveries of modern astronomy. It had been long observed that the position of the stars under- goes certain variations which do not in the least correspond with the apparent motion of one degree in 72 years, which is roduced by the precession of the equinoxes. The Abbé Picard had remarked these variations in the pole star as early as 1671, but he had neither attempted to reduce them to a constant rule, nor to assign any cause for them. The very numerous observations of Dr. Bradley presented him not merely with the variations observed by Picard, but with many others which had not so much as been suspected. He met with some stars which appeared durmg the course of a year to change their longitude without any alteration in their latitude; others appeared to alter their latitude without any alteration in their longitude ; while others, and this was the case with the greatest number, appeared to describe a small ellipse more or less elongated. The annual period which all these movements, so different from each other, affected, soon led to the mference that the motion of the earth was intimately connected with the pheno- mena. But the difficulty was to explain in what way it could produce such effects. The first attempts of Dr. Bradley to obtain an explanation were unsuccessful. But his perseverance was at last crowned with success, and enabled him to discover that all these apparent motions in the stars were the result of the succes-- sive motion of light combined with that of the earth round the sun. It had been long believed that the velocity of light was, physi- cally speaking, infinite. M. Roemer was the first who ventured to affirm that this opmion was inaccurate, and even to assign the time which light takes to traverse the diameter of the earth’s orbit. He had observed that the emersion of the first satellite of Jupiter became later and later in proportion as Jupiter became further and further removed from the opposition ; and that this retardation in an eclipse the nearest possible to the conjunction amounted to 11 minutes. He was of opinion that these 11 minutes constituted the time that the first ray of the satellite, when it emerged, took in traversing the distance between the two positions of. the earth, when near the opposition and near the conjunction; and consequently that the velocity of light is not merely finite, but measurable. However reasonable this explanation is now esteemed, it was then thought too bold; and it was not till long after the death of Roemer that astronomers unanimously agreed that the motion of light was successive. It was from this successive motion that Dr. Bradley obtained the a of the irregular varia- x 324 Biographical Account of [May, tions which he had observed in the stars, and to which he gave the name of the aberration of the fixed stars. Let us now endeavour to communicate to the reader an idea of his expla- nation. Let us conceive piles of small bodies moving in directions arallel to each other ; as, for example, a rain without any wind, falling down perpendicularly. Let us expose to this rain an immoveable tube placed in the same vertical position. It is obvious that the drop which enters at the upper orifice of the tube will pass out at the other end without touching the inner walls of the tube. But if we make the tube move parallel to itself, though its position always remains parallel to the direction of the drops of rain, it is obvious that the motion of the tube will cause the drops to strike against one of its sides, and that the sooner, according as the motion of the drops is slower, compared with that of the tube. And it is easy to demonstrate that if the motion of both be equal, the drop of rain which falls upon the centre of the upper opening of the tube will strike the inside wall after having traversed exactly half the semidiameter of the tube ; and that its direction in consequence will make an angle of 45° with the axis of the tube. Hence it follows that if we wish the drops of water not to touch the tube notwithstanding its motion, we must incline it 45° in the direction of its motion. If this motion were to take place in the circumference of a circle, the tube would describe round the vertical line passing through the centre of its base, a cone, the angle of which will be 90°. What has been said is meant to show that the inclination of the tube in order to allow the drops of rain, notwithstanding the motion, to pass through the tube without striking againstits sides, depends entirely upon the proportion between the velocity of its motion and that of the drops of rain. The greater the velocity of these drops compared with that of the tube, the less will it be necessary to incline the tube. Hence if the velocity of the drops were infinite compared with that of the tube, it would not be necessary to incline the tube at all; because the drop would reach the bottom of the tube the very instant that it entered its top, and the tube, during such a space of time, could advance only an infinitely small quantity. , When we apply this theory to the aberration of the stars it is easy to see that the lines traversed by the drops of rain are the rays proceeding from the stars ; that the tube which we have supposed at first at rest, and afterwards in motion, is that of the telescope, which serves to determine the position of the stars, and which is always carried away by the motion of the earth round the sun; and finally, that the velocity of light being finite, when compared with that of the earth in its orbit, the telescope must change its position in proportion as this motion changes its direction. Hence it follows that each star must have a series 1820.] Dr. James Bradley. 325 of different positions, or, which comes to the same thing, an apparent motion in the heavens, which will make it describe in a year ellipses more or less elongated according to the position of the star. Such is the theory of the aberration of light which Dr. Brad- ley published in 1727, and which was received by astronomers with that applause which it deserved. M. Clairaut made it the subject of an excellent memoir printed in the Memoirs of the French Academy of Sciences for 1737, in which he examined the theory of aberration to the bottom, and gave the rules neces- sary to apply it to practice. The result of his calculation is, that the velocity of light deduced from the aberrations observed in the stars is absolutely the same as that assigned it by the ingenious explanation which Roemer had given of the retarda- tion of the eclipses of the first satellite of Jupiter. This is a new proof of the accuracy of the hypothesis, if it stood in need of being proved, Three years after this glorious epoch in the life of Dr. Brad- ley, the place of Reader in Astronomy and Physics in the Museum at Oxford became vacant. It was bestowed upon him, and certainly no individual in the university was better qualified for the task thus assigned him. Dr. Bradley’s diligence as an observer was redoubled by the increase of his reputation. He gradually discovered that the inclination of the axis of the earth on the plane of the ecliptic was not constant; but underwent a variation amounting to some seconds, the period of which was nine years. This period seemed at first to bid defiance to all explanation. Whatcoulda period of nine years have in common with the revolution of the earth round the sun which is completed in one year? Dr. Brad- ley was, however, fortunate enough to find the true cause in the Newtonian theory of attraction. The first principle of this theory, it is well known, is, that all bodies attract each other mutually directly as their mass, and inversely as the square of their distances. From this attraction combined with rectilineal motion, Newton deduced the orbits of the planets, and, in particular, the orbit of the earth. If that orbit were a circle, and if the globe of the earth were exactly spherical, the attraction of the sun would act only to keep it in its orbit, and would not derange the position of its axis. But neither of these suppositions is true. The earth is sensibly reatest at the equator, and its orbit is an ellipse in one of the foci of which the sun is placed. When the position of the earth is such that the plane of its equator passes through the centre of the sun, then the sun has no other action but that of drawing the globe towards itself; but always parallel to itself, and without deranging the position of its axis. This happens at the two equinoxes. As the earth recedes from these two points, the sun leaves the plane of the equator, and approaches to one or other 326 Biographical Account of (May, of the tropics, then the two semidiameters of the earth exposed to the sun, being no longer equal, the equator is more strongly attracted than the rest of the globe, which alters a little its posi- tion and its inclination to the plane of the ecliptic. And as the part of the orbit, included between the autumnal and vernal equi- nox is smaller than that included between the vernal and the autumnal equinox, it follows that the derangement caused by the sun, while it passes through the northern signs, is not entirely compensated by that produced while it passes through the southern signs; and that the parallelism of the terrestrial axis and its melination with the ecliptic remain a little altered. Hitherto we see nothing which has any relation to the period of nine years. We shall see immediately what produces this period. What the sun operates upon the earth by its attraction, the moon operates also, and it acts with the greater effect the more it deviates from the equator. But when its nodes concur with the equinoxial points, its greatest Jatitude is added to the greatest obliquity of the ecliptic. This then is the time of its greatest action to derange the position of the terrestrial axis. And the revolution of the nodes of the moon occupying a period of 18 years, itis clear, that during that period the nodes will be twice im the equinoxial points ; consequently, during that period, the axis of the earth will be the most deranged possible two several times. Thus the axis will be the most deranged possible once every nine years ; or, which comes to the same thing, it will have a vibration, the period of which will be nine years, as Dr. Bradley had observed. This vibration is what he termed the nutation of the terrestrial aais. He published an account of it in 1737. us within 10 years he communicated to the public two of the greatest discoveries in modern astronomy—discoveries which will always mark a memorable epocha in the history of the science. Dr. Bradley had always enjoyed the esteem and the friendship of Dr. Halley, at that time Astronomer Royal, but in a very advanced period of life, and unable to contribute as usual to the promotion of his favourite science. He conceived that he could not confer a greater favour on it than by endeavouring to procure Dr. Bradley for his successor. With this view he wrote to Dr. Bradley several letters, which were found among that gentle- man’s papers after his death, requesting permission to solicit for him the reversion of his office, and even offering, if necessary,'to resign in his favour. But Dr. Halley died before he was able to accomplish this desirable object. The Earl of Macclestield, however, well known for his attachment to astronomy, and afterwards President of the Royal Society, had sufficient interest to secure him the situation of Astronomer Royal. -As soon as the nomination was publicly known, the University of Oxford enrolled him as one of their own body by creating him Doctor in Divinity. 5 -1820.} Dr. James Bradley. 327 The situation of Astronomer Royal was the real element of Dr. Bradley. He devoted himself to observations with the most indefatigable industry ; so that the remainder of his life consti- tutes, so to speak, a portion of the history of the heavens. Though the collection of instruments at Greenwich was already very considerable, it was impossible that so ardent an observer as Dr. Bradley could avoid wishing for various others, both to ensure a greater degree of precision, and to suit his own articular views. At the annual visit of the committee of the yal Society in 1748 he laid an inventory of the apparatus before that learned body, and represented in such strong terms, the necessity of getting the old instruments repaired and new ones constructed, that the Society deemed it requisite to lay the representation before the king, who was pleased to grant 1000/ for the purposes pointed out by the Astronomer Royal. Messrs. Graham and Bird were immediately set to work, and the observatory was soon provided with the most complete set of apparatus, which the state of the arts at that time admitted. he observations made by Dr. Bradley were exceedingly nume- rous ; and it may be said with truth that they form the first collection of rigidly accurate astronomical observations ever presented to the public. They constitute a kind of epocha in astronomy, by rendering it necessary for all subsequent observers to provide themselves with instruments of the requisite delicacy and precision, and of taking the necessary pains to ensure the accuracy of their observations. Soon after his going to Greenwich to reside, the Rectorship of that parish became vacant, and it was offered to Dr. Bradley; but he was disinterested enough to decline the offer, fearing that his duties as a clergyman and as an astronomer might interfere with each other. George II. was so much struck with this disin- terested refusal, that he gave him a pension of 250/. a year in the beginning of 1752. The reason assigned was his uncommon skill in astronomy and in other parts of the mathematics, and the advantages resulting to the commerce and navigation of Great Britain from the application which he made of that skill. In the year 1747 Dr. Bradley was chosen a member of the Royal Aeademy of Sciences of Berlin: the year after, he was made Foreign Associate of the Academy of Sciences of Paris : in 1754 he became a member of the Imperial Academy of St. Petersburgh : and in 1757 of the Institute of Bologna. He continued his unremitting attention to the duties of his situation till towards the end of 1760, when he was seized with a malady that deprived him of his strength. Fortwo whole years he experienced no other inconvenience; but about the end of June, 1762, he was seized with a suppression of urine in conse- ni of an inflammation of the kidneys. Of this disease he ied on July 13, in the 70th year of his age. He was buried at Michin-Hampton, in Gloucestershire, in the same place where 328 Biographical Account of Dr. James Bradley. {[May, his mother and his wife had been already interred ; for in 1744 he had married Susanna Peach, the daughter of a gentleman in Gloucestershire, by whom he had a daughter, who survived her father, The most striking part of his character was the most perfect modesty and a sweetness of temper very uncommon in a man of his lively temperament, and capable of enduring the late nights and the intense application which occupied the whole of his life. His generosity was without bounds to those who required his assistance, and he was perfectly destitute of that selfishness with which literary men are so often reproached, Though he spoke well, and possessed the power of communicating his ideas with the most perfect clearness, he was remarkably silent, never intruding his opinion, Fue when it was necessary so to do. But when he thought that his conversation could be useful, he was not sparing of it. He even induced his disciples to put questions to him by the accuracy with which he answered them, and by the attention which he always paid to bring himself down to the level of those with whom he conversed. He was not more inclined to protrude his writings than his conversation upon the world. The consequence was that he published very little. He was so diffident of himself that he never was satisfied with his own compositions, and was induced to suppress a great many which probably were highly deserving of publication. Fortunately he was under the necessity as Astronomer Royal of communicating his observations to the Royal Society. The consequence was the preservation of the immense quantity which he had made. He became celebrated almost in spite of himself. His merit alone, without any attempt on his part to attract attention, pro- duced his reputation. In this respect he furnishes a striking contrast to some men of science of latter years, who have employed as much art and chicanery to attract the regard of the public, have caballed as much to detract from their supposed rivals; have made as great a sacrifice of truth and uprightness of conduct to secure to themselves a kind of monopoly of the particular science to which they had attached themselves, as if they thought themselves secure of blinding the whole of man- kind, and of appropriating to themselves that exact share of . reputation which they have thought proper to claim. Fortunately for the interests of science and of human nature this conduct has never in a single instance been ultimately successful. The cabals and the factions which have shut out the light from con- temporaries gradually disappear, and when the leader of a scien- tific party is subjected to the lynx-eyed scrutiny of posterity, they never fail sooner or later of detecting all the false preten- sions ; of discovering the vanity, the selfishness, the malignity, which our man of-science has displayed by his actions. The consequence is, that posterity not merely reduce him to the 1820.) Dr. Clarke on Crystallization of Sallad Oil. 329 exact place which he was entitled to occupy; but often place him much lower than the seat which his abilities and industry would have entitled him to occupy, had he been satisfied with that share of reputation which his real merit entitled him to obtain. The conduct of Bradley was exactly the opposite ; yet. few men enjoyed a higher reputation, or were more respected by all that was great and eminent in Great Britain or on the Conti- nent during his own life time ;-and few men have retained, or are likely to retain, a higher place in the most exalted and most perfect of all the sciences. Artic.e II. Regular Crystallization of Olive Oil. By Dr. Clarke, Profes- sor of Mineralogy, Cambridge. (To Dr. Thomson.) DEAR SIR, Cambridge, March 22, 1820. Aw accident has occurred within the last week which has enabled me distinctly to observe the regular crystallization of olive oil. The thermometer of Fahrenheit, during the late north winds, has frequently indicated a temperature below 40° at noon-day. Upon one of these occasions, when the mercury had fallen, towards evening, to 35°, some sallad oil, instead of exhi- biting the usual appearance, by congelation, of having lost its transparency, presented to the eye a number of white, Opaque, prismatic radii, rising upwards from the bottom of the vessel, and beautifully diverging in the transparent fluid. When examined with a lens, these prisms (which were as large as the capillary prisms of radiating arragonite in porous trap) were found to have the form of mesotype ; that is to say, rectangular four-sided prisms with square bases. The terminating planes, being squares, reflected the light mm such a manner as to enable me to discern their form in the most satisfactory manner. Several persons witnessed this appearance; and among others our geological Professor, Sedgewick, and Mr. Henslow, of St. John’s College. I endeavoured to preserve the oil in this state, but the weather becoming warmer, the whole of the fluid became transparent. Its crystalline appearance was, however, preserved during 24 hours; and often, during this time, examined. The inference I would deduce from this circumstance is, that the crystallization of this vegetable oil agrees with the general “acenga of crystallization characteristic of non-metallic com- ustibles ; among which the octahedron, whether regular, as in diamond; or obtuse, as in mellite; or acute, as in sulphur ; exhi- bits pyramids whose bases are squares. E. D. Cuarke. ° 330 Extract of a Letter from Mr. Breithaupt [May, Articte III. Extract of a Letter from. Mr. Breithaupt, in Freiberg, to Professor Gilbert.* You are aware that different chemists have found boracic acid in the tourmalin, axinite, &c. of which essential constituent the most celebrated former analyses have not taken the least notice. These researches were undertaken at my request. I have been employed these five years in endeavouring to construct a mineral system, which should indeed depend entirely upon the naturat characters and properties of minerals; but I wish it to be at the same time chemical, physical, and philosophical. Though it may, and indeed must appear to youa piece of bombast to affirm that it is the first system ever contrived, the assertion is true notwithstanding. I do not choose to publish an account of it till the whole has been put in better order, though it is true at the same time that a considerable part of it has become already, in some measure, known to the public. My fundamental maxim is, that individual minerals (and only crystals are individuals) owe their natural characters to thewr chemical constituents. Hence the shape of the crystals, the lustre, the electricity, the degree of hardness, the specific gra- vity, &c. must depend upon the nature of the constituents. But if these conclusions be true, it is obvious that little dependence can be put upon the chemical analyses of minerals, which we already possess. I have, for example, put boracite, tourmaline, anatase, andalusite (with respect to it | have been unsuccessful in my attempts to diseover an essential ingredient), and axinite, under one family. And as the external characters of these minerals bear a close resemblance to each other, I expect from my theoretic maxim, to which I have given the name of plasti- cism, to find an equal correspondence in the constituents. I, therefore, conclude, that as boron is an essential constituent of boracite, the same substance must also be an essential constituent of tourmaline, anatase, andalusite, and axinite. The proof that boron is essential to the boracite may be deduced from the prin- ciples of crystallography. Lampadius has already found about 16 per cent. of boracic acid in the tourmaline and axinite; and I now learn from my friend Christian Gmelin that he himself, Berzelius, Arfved- son, and Vogel, have made experiments which confirm this result. I have a treatise upon the family of schorls quite ready, and I shall make it known as soon as I can procure a good draughts- * Translated from Gilbert’s Annalen, Ix. 211. 1820.] to Professor Gilbert. 331 man to delineate 13 varieties of crystals. I shall state some of it here. The essential constituents of the schorl family are not confined to boron. They are 1. Electropositive. a. Either an alkaline earth or alkali. Among these the oxide of zinc is to be ranked ; perhaps even oxide of iron or manganese may be substituted ; or all of these may exist together. . Alumina. (It is essential even in boracite, which probably contains some per cents. more than is at present known.) It has still to be pointed out in anatase. 2. Electronegative. a. Silica, or rather quartz, for which oxide of titanium is sometimes substituted. b. Boron. (The appearances which the schorl family exhibit when thrown into red-hot saltpetre, demonstrate that, boracite, &c. contains a combustible substance (boron), not a product of combustion (boracic acid) ; although this last is the substance obtained by analysis. It is a product, not an educt. Boron is still to be found in anatase and andalusite. The substances upon which the system of crystallization, and consequently the species depend, are 1. In boracite (tetrahedral schorl) magnesia. Boracite is therefore a magnesian schorl. 2. In tourmaline (trigonal schorl) the quartz substance. It is therefore siliceous, or quartz schorl. 3. In anatase (tetragonal schorl) titanium. It is therefore a titanium schorl. 4. In andalusite (rhombic schorl) a substance not yet disco- vered experimentally ; very probably fluorine. 5. In axinite (rhomboidal schorl) boron. (This substance therefore, is not merely essential as a generic, but still more essential as a specific substance; and | first ascertained the © necessity of its presence in this mineral from theory.) It is consequently a boronic schorl. Boron is indeed an essential constituent of datholite ; but as in it the hardness of schorl is wanting ; so likewise is the consti- tuent which gives hardness ; namely alumina. You perceive that I have not reposed upon any authority. In all systematic disputes in the dominions of nature, the sole and ultimate arbiter is nature herself. And in the mineral kingdom nature has expressed here classes and orders by the external characters. In the schorls we perceive the same lustre, the same colours, the same play of light, the same polarity of crys- tallization (determined in my treatise), the same hardness, the same specific gravity, from 2°9 to 3°3 (and if that of anatase be correct, as high as 3°8), the same electricity, &c. Hence it is evident how completely nature has given us the means of classi- en 332 Letter from Mr. Breithaupt to Prof. Gilbert. [May, fying mineral bodies according to their characters. It is true that boracite has been arranged among the salts, like a fish with stag’s horns. Although its quartzy hardness, long ago well known to Ilsemann, showed clearly that it belonged to the precious stones. I presume likewise that boron exists in helvine, dioptase, sphene, cyanite, tetrahedral fahlore, and even in Rothgilti- gerze. I am almost certain that boron is a constituent of wolfram. All this is nothing to the number (above 40 species, according to Werner’s system) of minerals in which theory has pointed out to me the existence of ch/orine as an essential constituent some- times generically, sometimes specifically, though analytical chemistry has not been able hitherto to verify these theoretical conclusions. Thus it exists in schaumkalk, talc, mica, schiller- stone, felspar, cyanate, &c. and in many uncrystallized minerals, as steatite, serpentine, nephrite, chalk, mountain soap, fuller’s _ earth, &c. One will not easily miss chlorine in a fatty, soft mineral, and the talky properties are produced not less by it than by magnesia. As chlorine and iodine resemble each other very closely, but the latter has more of the metallic properties, I presume that both, but more probably the latter, exists in graphite, molybdena, blattererz, black earthy cobalt, manganschaum, &c. A person may easily satisfy himself that the essential constituent of graphite is not yet known, and that a substance exists in it which has not yet been shown experimentally to constitute a part of the mineral kingdom. But I must be shorter than I have been. I write at present on purpose to obtain the assistance of chemists. Already has chemistry been of the greatest service to mineralogy; and it is now time that this last science should atone for her faults towards her benefactor. I hope within a year to publish a System of Mineralogy which will not merely consider crystals and crystallized species as belonging to pure natural history, but with respect to which chemists will have no reason to complain of intolerance. ; AveustT BREITHAUPT, Freiberg, Aug. 6, 1818. 303 1820.) 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Demonstrations of Theorems for finding the Sums of Sines. By Mr. James Adams. (To Dr. Thomson.) SIR, Stonehouse, near Plymouth, Feb. 8, 1820. Never having seen sny demonstrations of the theorems for finding the sums a: the sines sin. a + sin. (a + 6) + sin. (a + 2 b) et. ... sin. (a + nb) and cos. a + cos. (4 + b) + cos. (a + 2 b) + .... cos. (a + nb), I, therefore, beg leave to send you the following demonstrations thereof, the insertion of which in the Annals of “Philosophy will oblige, Your humble servant, James ADAMS. Prob. 1.—To find the sum of sin. a + sin.2a + sin. 3.4 + . sin. ma. Per Mr. Woodhouse’s Trigonometry, p. 54, d 1 ik, sn.a= ci} gv —1 x sn. 2a= : gett Brest 2) sin. 3a= ! de) a sin. va = fo 2Vv—1 ( =) Then per geometrical progression, rte eX4+R4+ 2 4 rye ot = EF and Erie 4 Se 1 x3 1 an — 1 A : : oeee — = ——, we then have sin. a + sin. 2a + sin.da x" a" (x — 1) 1 met hy | 1 + ... S52 2a&= a a ae ay =1,\' *-! x" (a — 1) 27) aera 1 ee 1 aie “23 ) (# -33) fps sf oneay.( ye re % 1 = {a ih a ST as a a Sat In (x ) eet gqv_1 a3 At ae 1 (2 —1. sin. 3 wa) (24 — 1. sin. — a) 1 : 2 ¢ ae 2V/—1 x sin da 2/—1 n+ 1 sin. ma x sin, a : sin. $a , 336 Theorems for finding the Sums of Sines. [May, a —Sin. a + sin. 2 a + sin. 3 a &e. ad infinitum = 4 cot. $ — Eo ieMeten sin. Lna@ X sin.{La a na) = 10s. 2 a—tcos.(a+ na) But » a being infinitely great, }@ + n a will likewise be infi- nitely great, and as the cosine of an infinitely great arc may be nothing, we shall have sin. a + sin. 2a + sin. 3 a, &c. ad infi- 4 cos. $ a nitum = =tcot.ia sin. 5 a Prob. 2.—To find the sum of cos. a + cos.2 a + cos.3 a + eeu COS, 1.0. Per Mr. Woodhouse’s Trigonometry, p. 5, 1 l cos. a = + (x ae =) “.2cos.a=axa+-— xv x . 1 9 : 1 cos, 2 a, ite +a} 2cos.2 4 =2* + — x z 1 1 cos.d34a= r(a + =) “.2cos.c@ = 2 + — 2 2° x eeceeseeeeeoeeeseeeerereweeeorer eee ene ee eeseen 1 cos. mae (2 + — =z) 12 cos. naz xv+— ax Then by geometrical ET we have ° : a erl—g 1 rftar4+2> +at+ ....8 = =o =* and+ + — i 4+5 + Letts So e@,eee x — an (a — Ly Therefore cos. a + cos. 2a + cos.3a + ....co8s.na =} 2 eae a — 1 ) = Seas «—l xz” (a —1) o a" (x — 1) es att ] “l (Guero Mee) ee ee See cos. ~G yi me Ae i L 2 J 7 Corollary.—Cos. a + cos. 2 a + cos. 3 a, &c. ad infinitum _- — 1 ye : : ; 1 ; Per trigonometry, sin. 1 ma x cos. e a+ ~ 4) == 1 sin. sin. $a ( a+n a) — $sin.}a, but x a being infinitely great, +a + n a will likewise be infinitely great ; and as the sine of an infi- nitely great arc may be nothing, we shall have cos. q + cos..2 a + cos. 3 a4, &c. ad infinitum = pat dR ees sin. $ a z Prob. 3.—To find the sum of sin. a + sin. (a + 5) + sin. (a +26) + .... sin. (a + 7B). 1820.] Theorems for finding the Sums of Sines. 337 Per trig. sin. a = sin. a sin. (a + 6b) = sin. a cos. b + sin. b cos.a sin. (a + 2 6) =sin. a cos. 26 + sin. 2 b cos.a sin. (a + 3b) = sm.a cos.3 6 4+ sin. 3 b cos. a sin. (a + 1 b) = sin.a cos.n b + sin. nb cos. a Then by problems the first and second, we have the sum of the series = Ne : : : : n+l : : sin.a x sio.5b+sin. $nbx sin.a x cos, —6 + sin. nb x cos.a x sin, a b sin. 56 sin.a x sin. $b + sin. (a + $6 + $nbd) x sin. dnd =» sin. 3 6 ag g sin. (a + $nb) x sin. 3 (n+ 1)6 (I.) sin. 56 For sin.a x sin. b = 1 cos. (a — 1 b) — 1 cos. reper And sin. (a + 16+ inb)sin.inb oe cos. (a + in b) —icos.(a + 2b + nb) Therefore, sin.a x sin.+6 4+ sin. (a + 2 = 7 cos. (a — 1b) — 1 cos. (a + But sin. (a + 1” b)sin. (4 6 + 1nd) tcos.(a+ib+nb) “a the equation marked (I.).is evident. Corollary.—Sin. a + sin. (a + 6) + sin. (a + 26) + sin. cos. (a— $5) (a + 3b) &e. adinfinitum = rales For in this case » b is infinitely great ; therefore a + + Lh + n b is infinitely great; and since the cosine of an i fnitely great are may be zero, therefore the sum of the series = $ cos. (a—§b) __ cos. (a — 15) sin.gb 0 -)~)SCO2sing 3 Prob. 4.—To find the sum of cos.a + cos. (a + 6) + cos. (a+ 2b)+ ....cos.(a + nb). Meriric. GOS.@ ...... = COS. a cos. (a + 6) =cos.a.cos. hb —sin.a.sin. b cos. (a + 2b) = cos. a.cos.2 6—sin. a. sin. 2 6 cos (a + 3 b) = cos.a.cos.3 b — sin. a.sin. 3 6 b+ inb)sin.inb b+ nb) ere eee eee eee seeee . . . . eeee eee ceeP oer esos cos.(a + nb) = cos. a .cos. nb — sin. a. sin. nb Then by problems the first and second, the sum of the series = ‘ : n+l 5 soya l yoy. cos. axsin. $b + sin. dn b x cos. —>— b xcos.a — sin. 3 nb x sin, —> bxsin.a ———— cos.a x sin. $b + cos. (« + sin. 3b cos. (a + £nb)sin. $(n + 1) 5 ; a. * - $b vane (UL. PaL.cnV. No V. y 4 338 Col. Beaufoy ou the [May, For sin. + b x cos. a = isin. (a +16) —ism.(a — 1d) And sin. 4 nb x cos.(a+ 464+ inb)=tsmn.(a+ib +nb6)—ismn.(a + 16) Therefore cos. a x sin. 16 + cos. (a ee » otn almiente SY gh, CA 132-88 These 132-88 parts of barytes contain 13-8867 parts of oxygen; which approaches very nearly to the analysis of arseniate of lead. A portion of arseniate of barytes, which had not been dried, was digested in caustic ammonia, washed, dried, and exposed to a red heat. One hundred parts of this subsalt decomposed by sulphuric acid furnished 102°4 of sulphate of barytes. Hence the salt is composed of JATSENIC ACIG ocinesivtee OOF wisidie ave 100-00 AE UTES 19s! icptie wiser foyer ta (G) eee yee 199-04 But 132°88 x 12 = 199-32. Hence it follows, that the acid is combined in this salt with 11 times as much salt as in the neutral arseniate. Arsenite of Lead.—Arsenious acid was dissolved in caustic ammonia, and to separate all the excess of ammonia, the satu- rated solution was boiled for some time. It allowed a great deal of ammonia to fly off, and a crystalline deposit of arsenious acid took place. The liquid was left for some days in a temperature under 32° to get rid of all the excess of acid, which crystallized in octahedrons containing neither ammonia nor water. Then 10 grammes of pulverized and dry nitrate of lead were dissolved in water, and the arsenite of lead was poured into the liquid as long as any precipitate fell. The precipitate, being well washed and dried, was introduced into a glass retort, and fused. It produced a yellowish glassy mass, weighing 12:29 grammes. A small quantity of arsenious acid sublimed during the fusion, as always happens when the arsenites are exposed to heat; but its weight is included in the 12°29 grammes. To determine whether the whole oxide of lead of the nitrate was contained in the fused mass, I examined the liquid from which the arsenite had been precipitated. It became muddy on the addition of sulphuric acid, as was the case likewise with the water employed to wash the precipitate. The quantity of sulphate of lead thus obtained weighed 0356 gramme, equivalent to 0-261 of pure oxide of lead, which of course must be subtracted from the 6°731 grammes of oxide of lead contained in the 10 grammes of nitrate of lead. It follows that 6-47 grammes of oxide of lead had produced 12-29 grammes of arsenite of lead. Of course the salt is composed of Arsenious acid. .... 47°356 ...... 100-00 Oxide of lead ...... ! B2*Oae To. oss 111-17 But these 111-17 of oxide of lead contain 7-972 of oxygen. A solution of subacetate of lead was precipitated by arsenite of 72 4 356 Berzelius’s Experiments to determinethe Composition [Mavy, ammonia, prepared as above described, and care was taken not to precipitate the whole of the oxide of lead. The ay sia well washed and dried, was fused in a glass retort. The vitreous matter thus obtained was reduced to a fine powder.* Ten grammes of this powder were dissolved in nitric acid, and then precipitated by sulphate of ammonia. The liquid was then neutralized by caustic ammonia. This occasioned a small addi- tional precipitate, which was added to the former. The sulphate of lead, washed and dried ut a red heat, weighed 9°52 grammes, equivalent to 6°87 grammes of oxide of lead; so that in this salt, 100 of arsenious acid were combined with 219-5 of oxide of lead ; but 111-17 x 2 = 222°34. Hence it follows, that neglecting the inaccuracies of observation, the acid is combined in it with twice as much base as in the neutral salt. From these experiments, it appears to follow that the capacity of saturation of arsenic acid is 13°886, and that in the subarse- niates, the acid is combined with 1+ times as much base as in the neutral arseniates. The capacity of saturation of arsenious acid is 7°972; and in the subarsenites, the acid is combined with twice as much base as in the neutral arsenites. If arsenic acid, as we have stated above, is composed of 100 metal + 53°14 oxygen, it must contain 34°7 per cent. of that substance ; but if we suppose the quantity of oxygen in the acid to its capacity of saturation to be in the same ratio as we found for phosphoric acid; that is to say, that the acid contains 21 times as much oxygen as the base which it neutralizes, it fol- lows, that the quantity of oxygen in the arsenic acid is 13°8867 x 21 = 34717. Now this agrees perfectly well with expe- riment. In arsenious acid, we have found from 24:176 to 24-218 per cent. of oxygen. Its capacity for saturation is 7-972, which, multiplied by 3 = 23-916. The difference ought obviously to be ascribed to maccuracy of observation. In the subarsenite of lead, the acid contains 11 times as much oxygen as the base. The same ratio holds in the neutral phosphites. If we admit that the analysis of arseniate of barytes gave an exact result, and if we admit further that arsenic acid contains 214 times as much oxygen as the base by which it is neutralized, the result calculated for the composition of arsenious acid agrees perfectly with that found by the analytical experiments already pan ti It follows then, that the acids ought to be composed thus: Arsenic acid, Arsenious acid. Arsenic. .. 65:283 .... 100:000 ...... 75°81 .... 100-000 Oxygen. .. 84-717 .... 53:179 ...... 2419 .... 31-907 * The two arsenites of lead, both before and after fusion, are so idia-electric that it is difficult to pound them ina mortar, without a great part of the powder being driven out of the mortar by the electrical repulsion. 1820.] of different inorganic Bodies. 357 The analogous manner in which the acids of phosphorus and arsenic deviate from the general law of the combinations of oxidized bodies is a very remarkable circumstance ; and so much the more so, as these acids have a great deal of analogy in other respects. Phosphoric and arsenic acids form with the alkalies erystallizable salts, which, though proportional to the other neutral arseniates and phosphates, have an alkaline reaction; and if we saturate their solutions exactly by adding acid, and then concentrate the liquid by evaporation, the salt which crys- tallizes reacts as an alkali; while an acid and less crystallizable salt remains in solution. Both arsenic and phosphorus give with hydrogen combinations which have not acid characters, and which in their chemical properties differ completely from the combinations of hydrogen with sulphur, selenium, and tellurium. Both give degrees of acidification, between which the ratio of the oxygen is as 3 to 5, and in both, the greater number of the anomalies would disappear, if what we consider as the simple radical contained a portion of oxygen, amounting to one-fifth of what it absorbs in order to become an acid in zc. But I have already, in speaking of phosphorus, shown, that at present we have no probable reason for believing that it contains oxygen ; and the probability is still smaller for arsenic, which possesses most of the characters of metals. In the great number of the combinations of oxidized bodies which I have examined, the law of the multiples of the oxygen of the two oxides combined is always followed, except in the compounds formed by the acids of arsenic, phosphorus, and azote, when we consider this last as a simple substance. In the acids formed by these radicals, the ratio of the oxygen of the acid in ous is to that of the acid in ic as 3 to 5. In the neutral arseniates and phosphates, the acid contains 24 times as much oxygen as the base, and this ratio exists likewise in some subnitrates. In all the arseniates, phosphates, and nitrates, the oxygen of the base is a certain submultiple by 5, or, more rarely, by 10, of the oxygen of the acid (with the exception of some phosphates of lime). This may give rise to the following ques- tions: Does the law of multiples of oxygen in the two oxides combined (that is to say, that the oxygen of the one is a multiple by a whole number of the oxygen of the other) hold in all cases, except those in which the radical has two degrees of acidifici- tion, the oxygen of which is in the ratio of 3 to 5? What is the. reason that in the compounds formed by these acids, it happens so rarely that the oxygen of the acid is a multiple by a whole number of the oxygen of the base? It is evident that a satisfac- tory answer to these questions would be of the greatest import- ance to the theory of chemistry. It appears clear likewise that if we prove hereafter that azote is an oxide, which is probable, and which will be determimed when the phenomena of Abs reduc- tion of ammonia by the electric pile have been better studied and 358 Berzelius’s Experiments to detérmine the Composition [Mav, explained—it appears clear, I say, that we shall then have a key to explain similar anomalies, exhibited even by the acids of phosphorus and arsenic ; though such an explanation may have little probability at present. Experiments rendering the Existence of an Oxide of Arsenic probable.—Some authors pretend that metallic arsenic exposed to the influence of the air falls into a black non-metallic powder ; and Bergman advises us to keep arsenic under water. [ had an opportunity of verifying this property of arsenic in an experiment in which 100 arsenic in a vessel covered with paper, after an interval of some months, had acquired almost eight parts in weight, and afterwards ceased entirely to acquire more. The black powder thus produced was insoluble both in water and in acids; but when digested in muriatic acid, it assumed the metallic lustre, and the acid was found to contain arsenious acid in solution. When strongly heated, it gave out in the first place arsenious acid, and then left a residue of metallic arsenic. In short, this powder possesses the characters of the class of oxides, to which | have ventured to give the name of suboxides; and which, without being able to combine with other oxidized bodies, are decomposed by very slight forces, a portion of their radical being reduced, while another is carried to a higher and more stable degree of oxidation. As the quantity of oxygen found in this suboxide is a fourth of that of arsenious acid; without, however, being likewise a simple submultiple of the oxygen in arsenic acid, I wished to examine its composition anew; but to my great surprise, I was unable to procure arsenic, which falls in powder in the air. I have small quantities of metallic arsenic exactly weighed, which have remained for three years in glass vessels covered with paper, and which have not acquired any additional weight.” I do not know what constitutes the difference between the metallic arsenic, which falls to powder, and that which remains unaltered, nor have I any idea of the different processes to be followed in order to obtam the one or the other. { endeavoured then to produce an oxide of arsenic in combi- nation with an acid. I heated arsenic in a phial filled with muriatic acid gas. The arsenic underwent no change; but a small quantity of puce-brown matter sublimed. The muriatic acid gas was not absorbed, and no smell of arseniuretted hydro- gen gas was perceived when the gas was passed into the air. The brown matter was not altered by water; but on adding a little caustic potash, it detached itself immediately from the glass, recovered its metallic lustre, and fell into light scales which swam in the liquid. This experiment seems to indicate an action between muriatic acid gas and arsenic, though too weak to draw any certain conclusions from it. I then mixed three parts of calomel with one part of metallic arsenic, and distilled them together. There were formed in the first place 1820.] of different inorganic Bodies. 359 some drops of a liquid which distilled over, and which was the anhydrous combination of muriatic and arsenious acids. Then a sublimate rose ofa deep red colour, which lined the inside of the tube; and lastly, an amalgam of arsenic covered the inside of the red sublimate. I separated them, and mixed the non- metallic mass with a new dose of metallic arsenic, and sublimed it anew by a very gentle heat. The sublimate was at first trans- parent, and of a fine red, inclining a little to yellow; but as it became thicker, it acquired a darker shade, and lost its transpa- rency. The metallic arsenic remained in the phial. The subli- mate was easily detached from the glass. Its colour was brown, its fracture earthy, without any marks of crystallization, and its powder yellow. It was insoluble both in water and muriatic acid, Copper rubbed with the powder moistened with muriatic acid was not attached. Mixed with iren filings, and exposed to heat, it gave out arsenic, which sublimed in crystals. The fixed caustic alkalies decomposed this mass almost instantly ; and so did ammonia after a short interval. Muriate and arsenite of the alkali were found in the liquid, and there remained an amalgam of arsenic. Hence the sublimate was a double salt, having for its bases protoxide of mercury and oxide of arsenic, which, as happens with the oxides of sulphur and of phosphorus, is decom- posed the instant it is disengaged, producing arsenious acid, and allowing a part of its radical to be reduced to the metallic state. In this case, the metallic arsenic had likewise reduced the mercury, so that its quantity was so much the more reduced. I have no doubt that it is possible to obtain the combination of muriatic acid with oxide of arsenic without the presence of proto- muriate of mercury ; but I have not made the necessary experi- ments either to determine this point, or to find the quantity of oxygen with which the arsenic is combined to constitute the oxide ; so that I cannot say whether the oxide of the double salt of which I have just given the description, is the same as the black oxide formed by exposing metallic arsenic to the air. Sulphurets of Arsenic.—Klaproth and Laugier made experi- ments on the native sulphurets of this metal, and each of them obtained the same results. M. Haiiy having had reason to suspect that these two sulphurets have the same primitive crys- talline form, he concluded that their chemical composition must also be the same, though the external characters were altered by some accidental mixture. M. Laugier, while occupied with these researches, found that the two native sulphurets, when heated in a phial, gave a sublimate of arsenious acid, which was more abundant from the red sulphuret than the yellow. The fused mass thus deprived of arsenious acid had always the same composition. He found in the red sulphuret 43°67 sulphur in 143-67 of sulphuret, in the yellow sulphuret 61-66 sulphur in 161-66 of sulphuret, and in the fused sulphuret, from which the arsenious acid had been driven, from 71°3 to 71:89 sulphur in 9 ~ 360 Berzelius’s Experimentstodeterminethe Composition [May, 171-3 of sulphuret ; that is to say, in 100 parts of metallic arse- nic. Hence he concludes, agreeably to the conjecture of Haiiy, that these native sulphurets were probably combinations of the sulphuret obtained by fusion with different quantities of arsenious acid. The want of correspondence between the composition of the sulphuret of arsenic obtamed by fusion in the experiments of Laugier, and that of the acids of this metal, induced me to exa- mine these native sulphurets with this object im view, and to avoid all error from combustion, 1 exposed them to heat in vessels previously freed from air. The sulphuret melted and formed a brown transparent liquid, which required a very strong heat to be distilled over. I left it a long time at a temperature little lower than that at which it boils, without any trace of arsenious acid subliming. Afterwards, on increasing the heat, the sulphu- ret boiled, and distilled over in yellow drops. In these experi- ments, no trace of arsenious acid could be perceived; but on making the same experiment in an open phial, the sulphuret underwent a kind of roasting, in consequence of which sulphur- ous acid gas and arsenious acid were disengaged, the former of which made its escape, while the latter crystallized in the upper part of the phial. Let us now examine the composition of the native sulphurets of arsenic. In the first, place, they contain only sulphur and arsenic. Laugier found that the yellow sulphuret contains 38°14 per cent. of sulphur. In the yellow brilliant substance obtained by precipitating a solution of arsenious acid by sulphuretted hydrogen gas, there are, according to experiments already stated, 39 per cent. of sulphur; that is to say, that 100 parts of arsenic are combined in it with 64°33 * of sulphur. We know that orpiment is more or less sensibly mixed with realgar, which probably is never wanting. This circumstance ought to diminish the quantity of sulphur found in it by analysis. Hence the reason why analysis gave 38°14 instead of 39 per cent. of this last substance. Laugier and Klaproth found in realgar 100 arsenic united to 43°67 sulphur; but this quantity is very nearly two-thirds of 64°33. The precise quantity should have been 42-9 ; but it is to be presumed that realgar contains a mixture of orpiment, thereby containing a slight excess of sulphur ; just as we have seen the reverse to be the case with orpiment. I think then that we may admit it as established that orpiment and realgar are two different sulphurets of arsenic in which the quan- tity of sulphur is as 1: 123, or as 2:3. The yellow sulphuret is proportional to the arsenious acid, and the red sulphuret to a degree of oxidation, which contains two-thirds as much oxygen as arsenious acid, and which may be the oxide which we have seen combined with arsenious acid. The artificial sulphuret produced in the experiments of Laugier * 63:93.—T. Mine CLomentio Ch sew ac Sylosiae (4 Engraved tor D? Thomsons dinals—tor Baldwin, Gradock & Joy Luternoster Row MayL, 1820 Ps _ i) ‘i ow Goa 1820.] of different inorganic Bodies. 361 by the fusion of the natural sulphurets neither agrees with the composition of the sulphurets examined, nor with the acids of arsenic. From the theory of chemical proportions, it is obvious that it cannot be a simple sulphuret. It is probably the result of the combination of a higher degree of sulphuration with realgar. We know that arsenic acid is decomposed by sulphu- retted hydrogen gas. The resulting sulphuret must be composed of 100 arsenic combined with 106-91 of sulphur. If we calculate the composition of a combination of this sulphuret with realgar in which the arsenic in each sulphuret is in equal quantity, 100 of arsenic in it will be combined with 74°6 of sulphur. If, on the contrary, we admit a composition such that the sulphur of the persulphuret is double that of the realgar, 100 of arsenic in it will be combined with 71-26 of sulphur, which agrees perfectly with the analysis of Laugier. On examining the maximum of sulphuration of which arsenic is capable, I have found that this metal and sulphur. may be - mixed in almost all proportions. The sulphur for some time swims upon the surface of the fused sulphuret ; but by degrees it mixes with it into ahomogeneous yellow mass. Ihave in this way united arsenic with more than seven times its weight of sulphur. The sulphuret, when cool, was elastic, like caoutchouc, just as happens sometimes with sulphur itself, and some weeks elapsed before it became quite solid and hard. .The quantity of sulphur was determined by dissolving it in nitromuriatic acid, and precipitating the sulphuric acid by muriate of barytes. When we distill this sulphuret, it gives at first sulphur, containing little arsenic ; but as the process advances, the arsenic increases in quantity in the product distilled, which becomes at the same time more coloured; so that the last drops sublimed into the top of the retort have a fine ruby red. Hence it appears that heat does not furnish a method of obtaining the sulphurets of arsenic in the state of detinite combinations, (To be continued.) ARTICLE X. Memoir relative to the Lead Mines of Sardinia. (With a Plate. See CIV.) Tue mines in Sardinia have, there is no doubt, been wrought extensively at a very remote period. History relates, that both the Romans and Carthagenians carried on mining operations when they possessed the island. Zurita, in his history of the 14th century, as also the Genoese historians, Frederici and Giustiniano, state, that the silver which was on board the Pisau fleet, captured in 1283 by the Genoese, and which the latter 362 Memoir relative to [May, employed in defraying the expenses incurred in building the arsenal at Genoa, was the produce of the island of Sardinia. The great extent, and the irregular shape, of the excavations formed for the purposes of mining in Sardinia excite surprise ; and the appearances of what seems to have been an unprofitable waste of money and labour give rise to doubts as to what has been the actual cause of these works of the early miners. To suppose that the enormous excavations which remain have at any time been filled with solid masses of ore is impossible ; and it is equally difficult to believe that vast chambers, some of them formed in the shape of domes, and others as extensive square and circular apartments, should have been constructed without a view to gain. That these chasms are natural is an idea which cannot for a moment be entertained; and perhaps the most satisfactory way in which to account for their existence is to coneur in a tradition prevalent in the island, that constructed at first for the purposes of the miner, these caverns served in after times as a residence for the natives, when domestic feuds _ of a political nature, or when hostile invasion, desolated the country. For these purposes it is conjectured that the mines have been gradually enlarged and altered till they assumed their present form; and that, like the Gothic inhabitants of Spain, who are known to have sought a similar species of shelter to escape the tyranny of their Moorish conquerors, the Sardinians were wont to seclude themselves in these subterraneous dwell- ings to preserve the freedom, the mheritance of their northern ancestors. The entrances to these caverns are constructed upon several different plans ; in some it is merely a horizontal creek in the rock ; in others, it is wide enough to admit two coaches abreast ; and in some it is a door of about seven feet six inches in height, and four feet three inches in breadth. In most of these excavations, the ore appears to have been thoroughly wrought out, as hardly the least spark of it can be detected at present; and if the great number of mines in different districts of the island be considered, the wealth which the ancient possessors of the mines must have derived from them must have been immense. The high grounds of Sardinia are composed of granite ;* under this is a stratum of limestone, of the great thickness of 80 or 90 fathoms, of a compact and brittle texture, and of a whitish colour ; and under this is generally a stratum of a brownish coloured schistus, frequently intermixed with some of a blue colour. In this limestone are situated the lead veins in a matrix * The granite on the summit of the mountains here shows considerable appear- ances of stratification, which gives rise to a conjecture, that it rests ina stratum above the limestone, and does not penetrate through the strata of limestone and schistus, and thus form the base on which the last mentioned strata rest, according to the received opinion ef geologists respecting the nature of granite mountains. 1820.] the Lead Mines of Sardinia. 363 ‘of barytes, calcareous spar, or quartz; and in the district called Cape of Cagliari, we can travel but a very short distance with- out crossing in our path many of these veins, the most of which bear a good rib of ore to this day. Their positions evidently indicate that they must form numerous intersections, and would afford profit if wrought with any tolerable degree of skill. The mines at Iglesias are at present wrought by the Sardinian government: in the course of 80 fathoms, 11 different veins have been discovered, and the whole of these have afforded a large quantity of excellent ore in the course of the few partial trials which have been made. The ravines which intersect Sardinia in all directions preclude the necessity which so often exists in England of spending years in dead ground, where the only profit to be expected is that of rendering the adjoining veins accessible, and where so great an outlay of money generally takes place. Wood can also im Sar- dinia generally be procured close to the mines free of expense ; and these advantages are only in some degree counterbalanced by the unfavourable climate, the scarcity of water for washing the ore, and the barbarous state of the inhabitants of the country. In driving the main level of the lead mine at Iglesias, so soon as a vein had been found, the plan had been to proceed imme- diately to excavate; and so long as some particular danger or inconvenience had not impeded the labour it had been continued. As the sides of the vein, however, were, in general, left untouched, this could not long continue ; and when once aban- doned, a new vein had been begun upon, and treated in the same manner. The irregularity of these workings is of course such as to preclude the possibility of making ai instrumental survey of them. A written description, and a sketch of the mine Domenico Rosea near Iglesias is, however, annexed, which it is hoped will convey a tolerable idea of the workings. When the position of the veins in this mine, and their proxi- mity to each other, are considered, doubts cannot be entertained as to their forming many intersections, and thus affording the most favourable prospect to the miner. There is also a stream of water near the mine, and a convenient situation for a smelting house. The mine of Monte D’Oro, near Iglesias, is also one of the most extensive and ancient in the island. Here is, perhaps, the best example of the mines having been used as a permanent residence: the entrance has been faced or built with finely cut stone, and within the mine, shafts or sinkings lead from one set of subterraneous galleries to those below. The workings are so intricate and extensive that the guides are obliged to place small sticks in the path by which they conduct the strangers to enakle them to return in security. May not these have served for the dwellings of the exiled Romans when Sardinia was a place of 364 Memoir relative to [May, banishment for the Roman criminals? At the entrance of the mine are the ruins of a number of stone buildings. The small city of Iglesias is finely situated at the base of a range of mountains, whose sides near the town are planted with gardens, and richly cultivated and ornamented with orange grounds. The houses of the town are but indifferent; but the streets are cleaner and better paved than those of Cagliari. When the Pisans wrought these mines, this was their station : the air is wholesome, and“the town is well supplied with water from wells of six or seven fathoms deep: it may certainly be described as one of the most desirable places of residence in Sardinia. It contains about 1,500 inhabitants. The hills in which the mine Domenico Rosea is situated is not extensive, being only one English mile and a half in length, and _three quarters of a mile in breadth. The mountains in the neigh- bourhood bear so close a resemblance to it in structure and shape as to warrant the conjecture of their being equally produc- tive in lead veins. _ At Monte Bergani, about three miles to the east of Iglesias, and situated on the western declivity of the mountains, a trial has been made by means of an open cast, about four yards in length and one in breadth, and a beautiful vein of this breadth has been exposed. It has a rib of ore up its centre of about four inches wide, and the matrix is flesh-coloured barytes. This vein is studded with ore, and the rib increases in_ breadth downwards. The ore which was produced in the upper part of the vein was close-grained, and apparently rich in silver, but deeper ; it resembled the potter ore of England. The roads in the vicinity of this rich vein are good, and there is atolerable supply of wood and water in the neighbourhood. A view of the strata in the neighbourhood of the road which leads from Iglesias to Flumini Majore is to be had during almost the whole distance ; a brown or bluish argillaceous schistus may be seen below, and the thick stratum of whitish limestone, before-mentioned, resting upon it. At Flumini Majore the natives talk of the existence of an ore of silver, but the specimens of this metal occurring in the state of any of its ores in the island are now so scarce as to throw some discredit on the statement of Captain Belly and Count Vargus, both of whom represent even native silver as of common occurrence in the island. Close to the village of Flumini Majore is the Vein Pietro di Fuoco. In it there is a rib of free potter ore 11 inch thick. This strong vein of flesh-coloured barytes stands in some places seven feet above the adjacent surface; the weather having acted upon the adjacent limestone rock must have washed it away, while the more insoluble barytes remained unaffected. The open cast by which the vein has been tried is about 10 yards in length, two feet in breadth, and seven feet deep. It bears 82° S.W. ee ————————— 1820.] the Lead Mines of Sardinia. 365 At La Miza dili Ano Maruduis a vein of iron ore, of a fathom thickness ; some lead ore is mixed with it, and it bears 65° S.E. A vein of calcareous spar containing copper ore about three feet wide, and bearing nearly north and south, occurs at Mar- casita. ‘The sides of this vem are coated with a yellow mineral earth. bs The veins of St. Lucia and Johnny Longa in this neighbour- hood are also very promising. The latter bears 83° N.E. The village of Flumini Majore, near which the whole of the last mentioned veins are situated, is well supplied with wood and water; the roads for some distance around it are, however, bad; and, during the summer, the air is unwholesome, as the mountain streams in its vicinity are at that season nearly dried up, and form stagnant and noxious air in the plain surrounding the village. This small village, the houses of which are built of clay, is situated in a plain of about three miles in length, and one in breadth. High and rugged mountains surround it on all sides ; the inhabitants are either goat-herds, or earn their sub- sistence by cultivating the little valley in which they dwell. They are about 1000 in number, and although poor, they seem tolerably contented and happy. Between Flumini Majore and Monte Vecchio, and distant about four miles from the latter place, after ascending a steep acclivity situated across the head of a valley, a vein of flesh- coloured barytes is crossed by the road, and near it are seen other veins which seem to have at some period been tried. At Monte Vecchio, there is a vein of flesh-coloured barytes, which promises well, and which is at present wrought by a Signore Malacria, and a Neapolitan merchant, who pay a duty of one-twelfth per cent. to the government for their privilege. The mining here is conducted in the same unskilful way as at Iglesias, the vein is simply followed till water flows in upon them, and here their labour has been abandoned for this reason, with a rib of ore a yard wide extending before them. This is one of the most ancient mines, and is supposed to have been a very profitable one. The present company at first drove a flank level to the vein, but as it ran downwards, they changed their plan, and adopted that of working by sinkings, which the flowing of the water also compelled them to relinquish. By beginning their level at the bottom of the hill all this inconve- nience might have been avoided. The point of the vein is due east and west ; it declines about two feet in six, and the stratum is limestone similar to that of Iglesias. At Monte Carna there is a promising vein of white barytes in a stratum of limestone. At Maishtalesch near Pula, about 10 miles south-west of Cagliari, there is a vein in a ravine through which flows a small brook, in which a rib of solid ore about five inches wide may be seen, It isin the limestone stratum, and bears 32° S.E. 366 Memoir relative to [May, At Sa Gruttu Exeda there are some indications of copper, and at Monte Santa, about eight miles south-west of Cagliari, there is a promising lead vein. Survey of the Mine Domenico Rosea, situated about two Miles to the N.W. of Iglesias. Remarks left Bear. and dist Ba opens 535 aes es 32 37 An opening forabed..... 40 Ancient cross cut built up.. 58 70 emo Gilet hese s cee es vats 100 Cross cut in St. Barber, vein 114 127 Pe CLIb ms o'r ate e eels ot 146 Cross cut St. Catharine.... 193 OTF 260 305 314 336 MRGARICUE . onc wear teee cs 350 WA OECD icc niclee Oe Wute 400 431 Sees POM MCI. odio. oe we we 448 469 St. Ephesia vein.......... 486 WE WO'CKGOSS SUES: Sos nls © cus cre 500 600 St: Antioch vem’... 0.0. 633 Sto Morris vein .6 acess oc 652 Bo Fr eo ea A a 692 760 800 . 13, N.W. Remarks right. An opening. Cross cut. Ditto Ditto Ditto Ditto St. Catharine vein crosses here, and causes a rib often. Loose stones. St. Francesco, vein of soft mineral earth. Craxs cut. Ditto. Ditto. St. John vein. A vein crosses here. Cross cut. Cross cut and rise. St. Joseph vein. Cross cut. St. Saturnim vein. No further accessible. The level is supposed to extend about 80 links further. No. 3, Cross cut. 25 8.W. 67 S.W. 39 Links. 88 Ditto. Points of the west cross,cut, No. 21. 52° S.W. 62 links. workings. 75° N.W. 10 links. Has communication here with the old Opens into the old workings on the right. 1820.] Analyses of Books. 367 31° S.W. 62 links. At the end of the first 20 links of this length, it opens into another cross cut, bearing 72 8.W. 46 links. 4°§.E. 66 links. Forehead. ARTICLE XI. ANALYSES oF Books. Reports on the Epidemic Cholera which has raged throughout Hindostan and the Peninsula 9f India since August, 1817. (Published under the Authority of Government.) Bombay, 1819. Tuts publication presents us with a very interesting account of the disease which has excited so much alarm, and committed such ravages in India for some time past : five places had escaped the malignant visitation ; and as it still continued its course una- bated in different directions, as neither the rapidity of its progress, nor the violence of its symptoms, seemed to be at all modified by the state of the atmosphere in respect to heat or cold, moisture or dryness, it is impossible to conjecture how far it may yet extend its influence. It is known to have appeared on board several ships, after their departure from India, on their return voyage ; and it is, therefore, not improbable’, that it may find its way to Europe at'no distant period. A similar disease is described by Sydenham, as having prevailed in England in 1669, and 1674, 1675, 1676, though it was neither so extensively propagated, nor of itself so fatal in its effects. Although, how- ever the Indian epidemic was almost uniformly fatal, when left tonature, itis consoling to observe, from these reports, that the mortality was very trifling, when medical aid was had recourse to at the commencement of the attack. The following extract gives a curious history of its progress : The cholera first appeared in August of last year (1817) in Zila Jessore, situated about 100 miles north-east of Calcutta. There had been no previous zaarked peculiarity in the weather. The preceding cold and hot months were no wise different from those of former years; and the rainy season was proceeding with its wonted regularity. To the authorities on the spot there, the disorder seemed at first to be of a purely local description; and attributable to the intem- perate use of rank fish, and bad rice. They were soon undeceived ; after nearly depopulating the town of Jessore, itrapidly spread through the adjoining villages; and ran from district to district until it brought the whole province of Bengal under its influence. It next extended to Behar; and having visited the principal cities west and east of the Ganges, reached the upper provinces. There its progress Was more irregular. Jenares, Allahabad, Goruckpore, Lucknow, Cawnpore, and the more populous towns in their vicinity, were affected nearly in the regular course of time; but it was otherwise in more thinly peopled portions of the coun- try. The disease would sometimes take a complete circle round a village, and leaving it untouched, pass on, as if it were about wholly to depart from the dis- trict. Then, aftera lapse of weeks, or even months, it would suddenly return, and, scarcely reappearing in the parts which bad already undergone its ravages, would 368 Analyses of Books. ~ has, nearly depopulate the spot, that had so lately congratulated itself on its escape. Sometimes after running a long course on one side of the Ganges, it would, as if arrested by some unknown agent, at once stop; and taking a rapid sweep across’ the river, lay all waste on the opposite bank. It rarely, however, failed to return to the tract, which it had previously left. After leaving a district or town, it sometimes revisited it, but in such cases the second attacks were milder; and more readily subdued by medicine than those in the primary visitation. The disorder showed itself in Calcutta in the first week of September, Few were seized in the beginning ; but of those few scarcely one survived. Each suc- cessive week added strength to the malady; and more extended influence to its operation. From January to the end of May it may be said to have been at its fullheight ; and during the whole of that period, the deaths in the city seldom by the police returns fell short of 200 a week. It in turn attacked every division, and almost every corps in the army. Of its fatal effects amongst the troops, a melancholy and signal instance is afforded in the history of its appearance in the centre division of the field army, under the personal command of the Most Noble the Commander in Chief, There it commenced its atfack on the 18th or 19th of November; was at ifs utmost violence for four or five days; and finally withdrew in the first days ef December, The division con- sisted of less than 10,000 fighting men: and the deaths within 12 days amounted at the very lowest estimate to 3,000; according to others, to 5,000, and even 8,000.* The average loss of rank and file was between 80 and 90 men a battalion. The epidemic was long in crossing the Bundlekund and Kewa Hills. It began to show itself at Jubbulpore on the 10th of April; prevailed generally amidst the corps posted there at Mundelah, Saugor, and other subordinate stations, to the Qist; and nearly disappeared before the end of the month, Here its influence was singularly irregular, In the same camp, and under circumstances precisely similar ; some corps were entirely exempt ; others had a few mild cases only ; and others again suffered very severely. The same irregularity held in different descrip- tions and classes of troops. The disease did not reach Colonel Adams’s camp till the 29th of May. It raged very violently during four or five days, and continued its operations in a desultory manner till the middle of the succeeding month. In Bengal and the middle provinces, it may now, perhaps, be considered as nearly at anend. Cases no doubt still now and then occur in Calcutta and its vicinity; but these are rare, ‘and should rather be reckoned sporadic, than as proofs of the sub- sistence of the epidemic. The returns from the different divisions of the army now leave the head of cholera morbus, in most cases, blank; and the reports of the civil surgeons are equally decisive of its general disappearance. At Delhi, Futti- gur, and others of the more northern stations, whither the disease was long in spreading, it is still, the Board believe, in full force, and producing the most alarm~ ing mortality. The epidemic continued its course in the same irregular man- ner, and reached Bombay in August, 1818. It is evident from these reports, that the disease presented itself in an infinite variety of forms; still the characteristic symptoms were the same in all, however much their order might be changed. Among the natives, the rapid approach of debility was principally to be dreaded, as the powers of nature seemed at once to be destroyed by the visceral congestion. Of this form of the disease, the extract which follows gives an excellent description. - The attack was generally ushered in by sense of weakness, trembling, giddiness, nausea, violent retching, vomiting and purging of a watery, starchy, whey-coloured, or greenish fluid. These symptoms were accompanied, or quickly followed, by severe cramps; generally beginning in the fingers and toes, and thence extending to the wrists and fore arms, calves of the legs, thighs, abdomen, and lower part of the thorax. These were soon succeeded by pain, , constriction, and oppression of stomach and pericardium; great sense of internal heat; inordinate thirst; and incessant calls for cold water, which was no sooner swallowed than rejected, together with a quantity of phlegm, or whitish fluid, like * The latter calculations must include the deaths among the followers of the eamp. 1820.) Reports on the Epidemic Cholera in India. 369 seethings ofoatmeal. The action of the heart and arteries now nearly ceased ; the pulse either became altogether imperceptible at the wrists and temples; or so weak as to give to the finger only an indistinct feeling of fluttering. The respira- tion was laborious and hurried ; sometimes with Jong and frequently broken inspi- rations. The skin grew cold, clammy, covered with large drops of sweat, dank and disagreeable to the feel, and discoloured of a bluish, purple, or livid hue. There was great and sudden prostration of strength, anguish, and agitation. The countenance became collapsed, the eyes suffused, fixed, and glassy, or heavy and dull, sunk in their sockets, aud surrounded by dark circles, the cheeks and lips livid and bloodless, and the whole surface of the body nearly devoid of feeling. In feeble habits, where the attack was exceedingly violent, and unresisted by medi- cine, the scene was soon closed. The circulation and animal heat never returned ; the vomiting aud purging continued, with thirst and restlessness; the patient became delirious or insensible, with his eyes fixed in a vacant stare, and sunk down in the bed; the spasms increased generally within four or five hours. The disease sometimes at once, and as if it were momentarily, seized persons in perfect health; at other times those who had been debilitated by previous bodily ailment; and individuals in the latter predicament generally sunk under the attack. Sometimes the stomach and bowels were disordered for some days before the attack, which would then in a moment come on in full force, and speedily reduce the patients to extremities. Such was the genera] appearance of the disease where it cut off the patient in its earlier stages. The primary symptoms, however, in many cases, admitted of con- siderable variety, Sometimes the sickness and looseness were preceded by spasms, Sometimes the patient sunk at once after passing off a small quantity of colourless fluid by vomiting and stool. The matter vomited in the early stages was in most cases colourless or milky ; sometimes it was green, In like manner, the dejections were usually watery and muddy ; sometimes red and bloody ; and in a few cases they consisted of a greenish pulp, like half digested vegetables. In no instance was feculent matter passed in the commencement of the disease. The cramps usually began in the extremities ; and thence gradually crept to the trunk ; some- times they were simultaneous in both; and sometimes the order of succession was reversed; the abdomen being first affected, and then the hands and feet. These spasms hardly amounted to general convulsion, They seemed rather affections of individual muscles, and of particular sets of fibres of those muscles: causing thril- ling and quivering in the affected parts like the flesh of crimped salmon ; and firmly stiffening and contorting the toes and fingers. The patient always com- plained of pain across the belly ; which was generally painful to the touch, and sometimes hard and drawn back towards the spine. The burning sensation in the stomach and bowels was always present; and at times extended along the cardia and cesophagus to the throat. The powers of voluntary motion were in every instance impaired, and the mind obscured. The patient staggered like a drunken man, or fell down like a helpless child. Headach over one or both eyes sometimes, but rarely, occurred. The pulse, when to be felt, was generally regular, and, extremely feeble, sometimes soft, not very quick, usually ranging from 80 to 100. In a few instances, it rose to 140 or 150, shortly before death. Then it was dis- tinct, small, feeble, and irregular; sometimes very rapid; then slow for one or two beats. The mouth was hot and dry; the tongue parched and deeply furredy white, yellow, red, or brown. The urine at first generally limpid, and freely passed ; sometimes scanty, with such difficulty as almost to amount to strangury 3 and sometimes hardly secreted in any quantity; as if the kidneys had ceased to perform their office. In a few cases the hands were tremulous. | In others the patient declared himself free from pain and uneasiness; when want of pulse, cold skin, and anxiety of features, portended speedy death. The cramp was invariably increased upon moving. Where the strength of the patient’s constitution, or of the curative means admi- nistered, were, although inadequate wholly to subdue the disease, sufficient to resist the violence of its onset ; nature made various efforts to rally, and held out strong bat fallacious promises of returning health. In such cases, the heat was sometimes wholly, at others partially, restored; the chest and abdomen in the Jatter case becoming warm, whilst the limbs kept deadly cold, The pulse would return, grow moderate and full, the vomiting and cramps disappear, the nausea diminish, and the stools become green, pitchy, and even feculent; and with all these favourable appearances, the patient would suddenly relapse; chills, hiccup, want of sleep, Os. mV. N° Y. 2A 370 Analyses of Books. [May, and anxiety would arise; the vomiting, oppression, and insensibility return, and in a few hours terminate in death. When the disorder ran its full course, the following appearances presented them- selves: What may be termed the cold stage, or the state of collapse, usually lasted from 24 to 48 hours, and was seldom of more than three complete days’ duration. Throughout the first 24 hours, nearly all the symptoms of deadly oppression, the cold skin, feeble pulse, vomiting and purging, cramps, thirst and anguish, conti- nued undiminished, When the system showed symptoms of revival, the vital powers began to rally, the circulation and heat to be restored, and the spasms and sickness to be considerably diminished. The warmth gradually returned, the pulse rose in strength and fulness, and then became sharp and sometimes hard. The tongue grew more deeply furred, the thirst continued, with less nausea. The stools were no longer like water, they became first brown and watery, then dark, black, and pitchy ; and the bowels, during many days, continued to discharge immense loads of vitiated bile, until, with returning health, the secretions of the liver and other viscera gradually put on a natural appearance. The fever, which invariably attended this second stage of the disease, may be considered to have been rather the result of nature’s effort to recover herself from the rude shock which she had sustained, than as forming any integrant and necessary part of the disorder itself. It partook much of the nature of the common bilious attacks prevalent in these latitudes, There was the hot dry skin; foul, deeply furred, dry, tongue ; parched mouth ; sick stomach; depraved secretions; and quick variable pulse ; sometimes with stupor, delirium, and other marked affections of the brain. When the disorder proved fatal after reaching this stage, the tongue, from being cream-coloured, grew brown, and sometimes dark; hard, and more deeply furred; the teeth and lips were covered with sordes; the state of the skin varied; chills alternating with flushes of heat; the pulse became weak and tremulous; catching of the breath ; great restlessness and deep moaning succeeded ; and the patient soon sunk insen- sible under the debilitating effects of frequent dark, pitchy, alyine, discharges. Among the Europeans, as might be expected, the disease assumed a character somewhat different from the above. Ac- cording to Mr. Crow, it was in them more neatly allied to tetanus than to cholera. This distinction was of great use as indicating the mode of cure. The following extract is from Mr. Crow’s report : In these corps the disease makes its appearance sometimes by the same affection of the stomach and bowels as in the natives, frequently with spasm in the feet, legs, abdominal muscles or arms ; but in all, the spasmodic affection is the pre-eminent one, head-ache, pain in the eyes, excruciatiug pain at the scrobiculus cordis (a pathognomic symptom of tetanus) quick, full, hard pulse (but labouring and oppressed according to the violence of the spasms), retention or difficulty of void- ing the urine, strong and violent spasm drawing up the legs, rigidly contracting the arms and fingers, bending the body forwards, or backwards, or laterally, the patient at the same time exerting such physical strength as requires half a dozen of men to hold him on hiscot, I have already said that the intestinal evacuations are watery and clay-coloureds this must not be lost sight of, as indicating a want of bile; the vomitings are somewhat of the same kind, attended with eructations, while the bowels are distended with flatus, These combined with a very distress-~ - ing tenesmus, not to be allayed by anodyne enemas, strongly point out that nature reqpires relief by the bowels. After the second day that the disease made its appearance in the 65th, Dr. Burrell commenced blood letting with the most decided advantage. This has, therefore, become the first grand remedy amongst the Europeans, and in which he has been followed by the practitioners in- other European corps, and with the same result. Bleeding quoad vires, the calomel and opiate, the hot bath, warm clothing, and frictions spirituous, or anodyne, form the chain of treatment in the European hospitals here; and these are repeated again and again as the symptoms may seem to demand. Under this system, and early application for relief, I think the disease is not fatal in a greater proportion than | in 100 cases, A fact is recorded in this volume highly honourable to the 1820.] Reports on the Epidemic Cholera in India. 371 Bombay government. When the epidemic approached that presidency, Sir Evan Nepean authorized the Medical Board to take whatever steps they thought as most likely to check its progress, or to alleviate the calamities which it might be expected to produce in so populous a place as Bombay. In consequence of this permission, as it was evidently impossible from the preju- dices of the natives to collect them: together in hospitals, a number of native assistants were hired and stationed in different parts of the island, in order to afford medical aid at the houses of those who might require it. For their instruction and guidance, a brief description of the disease, and of the mode of cure, was drawn up, and translated into the different languages which they understood. This most difficult and most important part of the arrangement was principally conducted by Dr. Taylor, from whose report we shall extract an account of the mode of treatment which was found most successful, with which we shall close our observations on this publication. The method of cure which, after consulting with you, I ordered to be used by the native assistants, was extremely simple. They were supplied with scruple doses of calomel, and a mixture composed of laudanum, essence of peppermint, brandy, and water, each ounce of which contained 50 minims of laudanum, 10 minims of essence of peppermint, three drachms of brandy, and four drachms of water, The calomel was first given in powder on the tongue, and then washed down with an ounce of the mixture. A similar dose was ordered to be repeated in two or three hours, if the patient derived no material relief from the former, or to be repeated immediately should the first be rejected, a circumstance, however, which very seldom happened. Besides giving these medicines, the assistants were directed, in all cases where it was practicable, to use the warm bath; and when, as it generally happened, this could not be done, to endeavour to alleviate the spasms, and the pain in the abdomen by fomentations with cloth wrung out of warm water, or by fomentations with warm bricks or tiles, or salt wrapped up in cloths. Frictions with warm spirits were also directed, which almost uniformly afforded great relief. The patients were ordered to be laid on a cot, underneath which, shigras, filled with warm ashes, were placed when it was necessary; ves- sels filled with warm water were also applied to the extremities. When by the use of these remedies the more violent symptoms were removed, but some pain or unea- siness in the abdomen still continued, and the bowels were not moved, an ounce, or an ounce and a half, of castor oil was given. In addition to the other stimulants already mentioned, I sometimes directed cloves and cardamoms to be taken, when the extremities were cold and the pulse feeble. Particular injunctions were given not to allow the patient to drink cold water; but to allay in some measure his urgent thirst, he was permitted sparingly the use of warm congee. The assistants were also enjoined not to suffer any one to be disturbed who felt a disposition to sleep. As the majority of cases were seen only by the native assistants, I have judged it proper to give this account of the general plan of practice they were directed to pursue. Considering every circumstance, the success attending it has been much much greater than could have been expected. The same practice was adopted by myself, with this exception, that usually L had recourse in the first place to bleeding, The accounts I had read of the disease, and of some dissections which showed a great congestion of blood in the abdominal and thoracic vessels, led me to conclude, that bleeding, in many cases, would be the most efficacious remedy. Accordingly it will be observed that I wished to try the effect of blood letting in one of the first cases, but was prevented by the unwil- Jingness of the patient, A day or two afterwards I was called to seea person who had been i!1 18 hours, and had received from one of my assistants two doses of calomel) and two laudanum draughts. At the time I saw him, though his mouth was affected, he had excruciating burning pain in the abdomen, with tormenting thirst 2a2 372 | Proceedings of Philosophical Societies. [May, and spasms, With some difficulty I prevailed on him to submit to bleeding, and took from him at Jeast 24 ounces. During the bleeding, the pain in the abdomen entirely ceased; and what is alittle singular, on his arm being tied up, helay down on his left side, which the people of the house said he had not been able to do before, though he did not complain of any uneasiness in the region of theliver. As slight spasms still continued, £ ordered him to be put into the warm bath. By these means, and the exhibition afterwards of a dose of castor oil, he entirely recovered. From this time, bleeding was very generally adupted in the cases which I had an opportunity of seeing: latterly also it was had recourse to by such of the assist- ants as had learned to bleed, and was sometimes even urged by the patients them- selvesand their friends, Io almost every case it relieved the pain in the abdomen and the spasms, and when the principal symptoms were great oppression at the breast, laborious breathing, and a sense of suffocation, or when the patient had trismus, or general tremors with giddiness, bleeding was the only remedy which afforded’ effectual relief. When it could be obtained, the usual quantity of blood taken away was 24 ounces, and no case occurred to me of the disease after such copious bleeding (for in a native it may be called copious) proving fatal. In two or three instances, however, it was fuund expedient to repeat the bleeding. But while bleeding in an early stage of the disease, and under certain circum- stances, almost uniformly produced the most decided and salutary effects, it was in general unayailing in the latter stages, or inthe worst forms of the disease, when the extremities were cold, the pulse could not be felt, and the eyes fixed and sunk. In such cases indeed it was impossible, as has been already observed, to procure a proper discharge of blood, which merely trickled down insmall drops; and open- ing the temporal artery was attended with no advantage, for by this means I never obtained more than two or three ounces of blood. Under such circumstances, no pulsation could be feltin the artery, and, except in one or two instances, the blood flowed out of it without any pulsatory motion. Almost the whole of these cases proved fatal. A few, however, in which the discharge of blood, though small, was followed by faintness aud profuse perspiration, terminated favourably. ARTICLE XII. Proceedings of Philosophical Societies. ROYAL SOCIETY. March 23.—A paper, by Mr. J. Hood, was read, entitled, “ On the Means of supplying Muscles in a State of Paralysis with nervous Power.” The author having remarked the effects of nitrate of silver in removing the spasmodic action of the urethra, when applied to a stricture near its orifice, concluded that this salt has the property of influencing the action of the nerves at a considerable distance from the place where applied. Observing likewise the slight discharge produced by an eschar made by tke nitrate of silver, he was induced to ascribe to it the power of exciting the absorbents to vigorous action by nervous communication, and in this manner he explained the good elfects of the remedy in question in a case of diseased knee joint, when applied so as to produce an eschar. Other cases were related in which the external application of nitrate of silver proved stimulating to the nervous system without proportionally increasing the action of the vascular system. Hence the author concluded that muscular spasm and paralysis are caused by 1820.] . Royal Society. 373 diminished nervous action; that muscular spasm cannot exist where the temperature is steadily above 90°, and that animal heat is produced principally by the action of the brain and nerves. Nitrate of silver, according to the author, applied to the head or spine, elevates the temperature, subdues spasm, and restores strength in certain paralytical cases; and applied to enlarged joints, produces a more rapid absorption than any other remedy. The Society adjourned till after Easter. April 13.—The Society resumed its meetings, and a paper, by Sir E. Home, was read on the Milk Teeth, and Organs of Hear- ing of the Dugong. The skull from which the following deserip- tion was taken, and which is the only perfect one in Europe, was sent from Sumatra by Sir Stamford Rafiles.. The milk tusks of this animal resemble those of the narwhale and elephant, being, like them, deficient in external smoothness, when com pared with the permanent tusks. But they are peculiar in havin a shallow cup attached to their base, apparently for the purpose of receiving the point of the permanent tusks as soon as formed, and for directing them forward in the same course as that of the milk tusks, and which is different from that in which the perma~ nent tusks were origiually directed. The milk tusks of the dugong have hitherto been mistaken for its permanent tusks ; but as no full grown individual has been yet examined, the form, &c. of the permanent tusks are unknown. The grinding teeth of this animal differ from those of all others. They consist of a double cone, the external crust of which is not enamel. This crust covers an internal harder coat, and the bulk of the tooth consists of soft ivory ; hence in wearing down, they will assume a concave form. _ The organs of hearing also in this animal are quite peculiar. The malleus and incus are fastened to the sides of the tympanum by a bony substance extending across the intervening space. The stapes is opposed to, but not connected with, the foramen ovale, nor isitanchylosed withthe ramus of the incus. The handle of the malleus projects in the centre of the circle over which the membranum tympani had been spread ; and hence, in the recent animal, is probably attached to the centre of that membrane As the habits of the dugong resemble those of the hippopotamus, Sir Everard was induced to examine the organs of hearing in the latter animal to see if they were similar to those of the dugong. He found them, however, very different, the ossicula auditus being detached from the skull, and readily dropping out at the external orifice. In the dugong, the semicircujar canals and cochlea are very small. Sir Everard was induced to conclude from the above remarkable construction of the organs of hearing, that this animal, perhaps more than any other, hears by means of vibrations conveyed through the bones of the skull to the ganals and cochlea. 374 Proceedings of Philosophical Societies. [May, ROYAL ACADEMY OF SCIENCES AT PARIS. An Analysis of the Labours of the Royal Academy of Sciences of Paris during the Year 1818. (Continued from p. 305.) PuysicaL Sciences.—By M. Le Chevalier Cuvier, Perpetual Secretary. CHEMISTRY. Chemistry has been enriched this year with two new substances which are doubly interesting ; because one is a substance not only metallic, but also alkaline ; that is to say, its oxide is a new fixed alkali; and the other is metallic, acidifiable, and more ana- logous to sulphur than to any other substance. We owe the first to M. Arfvedson, a young Swedish chemist, a pupil of Prof. Berzelius. M. Arfvedson discovered it in a stone called petalite, in which he did not find more than from three to five per cent. of it; but he afterwards found as much as eight per cent. of it in another stone called triphane. This substance affords very fusible salts, with the greatest part of the acids ; its carbonate, when melted, attacks platinum nearly as powerfully as the nitrates of the other alkalies, and is difficultly soluble ; its muriate is very deliquescent ; its sulphate crystallizes without any water of crystallization. The capacity of this alkali for saturating acids is much greater than that of any other alkah, and it also enters into the salts which it forms with the acids in a much greater proportion. The author of this discovery has given the name of dithion to this new substance, in order that we may recollect that this alkali was discovered in a mineral; whereas the other two fixed alka- lies were originally extracted from vegetables. The second new substance was discovered by Prof, Berzelius himself in a manufactory of oil of vitriol, at Fahlun, in Sweden. There is deposited on the floor of the chamber where the sulphur (distilled from pyrites) is burned, a reddish mass, which, for the most part, consists of sulphur ; but on being set on fire, it exhales a very strong odour of horseradish. Now this smell being one of the characters belonging to a metal discovered a few years ago by M. Klaproth, and called ¢ed/wrium, it was suspected that this smell was owing to a mixture of this metal with the sulphur. Nevertheless Messrs. Berzelius and Gahn, who first examined | this red substance, were not able to extract any tellunum from it. The first mentioned gentleman carried some to Stockholm, in order to examine it more closely, and found in it a very vola- tile substance, very easily reducible, and which was not precipi- table by alkalies. Its colour is grey, very shining, it 1s hard, friable, and its grain resembles that of sulphur. Its specific 1820.] Royal Academy of Sciences. 375 ravity is 3°6. It produces a red powder by trituration, is softened at the temperature of boiling water, a little above which it melts; and, while cooling, it remains for some time soft, plastic, and capable of being drawn out into threads in the same manner as sealing wax. At a temperature afew degrees higher, it boils, and sublimes in the form of a yellowish gas, and con- denses into beautiful red flowers, without undergoing oxidation. It evaporates in the open air in a red smoke, and burns with a blue flame, exhaling so strong a smell of horseradish that the thirtieth part of a grain is sufficient to infect the air of the largest room. Prof. Berzelius has given the name of se/enium, derived from the Greek name of the moon, to this substance, that we may recollect the affinity it has with tellurium ; an affinity which may, perhaps, only arise from the presence of selenium itself in every specimen of tellurium hitherto examined. These discoveries having been announced to the Academy by M. Gillet-Laumont, and soon afterwards confirmed by a letter of Prof. Berzelius written to M. Berthollet, M. Vauquelin imme- diately set about verifying the report with respect to the alkali ; and his observations have added some details to those which M. Arfvedson had given. Although M. Vauquelin had only a small quantity of petalite at his command, he found in it as much as seven per cent. of lithion. Prof. Berzelius has followed up his discovery of selenium with the great care that it merited. He has treated it with most of the chemical agents, and examined their actions upon it ; and, having come to Paris this year, he has given a very detailed account of his labours in the Annales de Chimie. He shows that, taking every circumstance into consideration, selenium is an intermediate substance between the combustible and metallic substances. He has exhibited comparisons between selenium, with sulphur and tellurium on the one side, and with chlorine, fluorine, and iodine, on the other : all of them substances which many chemists have lately wished to class along with sulphur, because the yield, like that substance, acids, by being combined with hydro- gen. What we have said on this subject in the analyses of 1813 and 1814, in giving an account of the new theory of Sir H. Davy, respecting those acids which he considers as being formed with- out oxygen, may be recollected. M. Berzelius finding the combinations of sulphur, tellurium, and selenium, with metals and combustible substances, to have a great analogy to one another, and on the other side, that the combinations of iodine and chlorine, with the same substances, have also a great analogy betwixt themselves and with those of oxygenized acids, though they do not resemble in the least the preceding, concludes from hence, that they constitute two very distinct orders of substances; and by this he shows 1 376 Proceedings of Philosophical Societies. [May, very plainly that he does not consider the theory of Sir H. Davy as being demonstrated. Selenium is excessively rare; 500 lbs. of sulphur, when burned in the manufactory of Fahlun, yields only one-third of a gramme. In how much smaller proportion then must it be in the pyrites from which the sulphur is extracted! Prof. Berzelius has since found it formimg about the one-fourth part of an extremely rare ore of silver and copper, extracted from a mine now aban- doned in the province of Smoland, in Sweden, which he had considered, on account of its smell, as an ore of tellurium. He has also found some specimens of it combined with copper without any silver. The more we reflect on these chemical elements, which appear to be scattered at random by nature in such minute quantities, that the most delicate exertions of art, and the most profound science, are required to discover them, the more we are led to believe that still more profound researches will hereafter strip them of their rank of elements. M. Gay-Lussac made some researches in 1811 upon the colouring principle of prussian blue, or that substance which has been called for some time the prussic acid. These researches showed that this substance, in astate of purity, had very remark- able properties, of which we were until then entirely ignorant ; such as, among others, the very small interval between its freez- ing point and that of its evaporation, and its dreadful power upon the animal economy. This experienced chemist, continuing his researches upon this important subject, discovered in 1814 that this principle was a hydro-acid ; that is to say, one of those sub- stances which resemble acids in their action upon other bodies, but in which the presence of oxygen could not be demonstrated, and which appear to be formed by the combination of hydrogen with a radical. The prussic acid is really the first hydro-acid whose radical is known in respect to its elements, as M. Gay- Lussac found that it was composed of carbon and azote in slightly different proportions. He called the radical cyanogen, and the acid produced from it hydrocyanic acid, on account of its property of giving a biue colour to oxide of iron. We announced all these discoveries in our Analyses for 1811 and 1814. M. Vauquelin has turned his attention to this subject, follow- ing, as, with his accustomed modesty, he expresses himself, the road which M. Gay-Lussac had marked out for him: neverthe- less this road had some branches which could not escape a man like M. Vauquelin. Gaseous cyanogen is absorbed by about four times and a half its bulk of water, and communicates a very sharp taste and smell to it, but without colouring it. This solution, in the course of some days, becomes yeliow, and afterwards brown; it depo- sits a brown matter, acquires the odour of hydrocyanie acid, and on the addition of potash, ammonia is developed. Nevertheless 1820.] Royal Academy of Sciences. 377 it will not yet form prussian blue. Further experiments showed that it contained hydrocyanate and carbonate of ammonia, and also ammonia combined with a third acid which M. Vauquelin calls the cyanic, but without absolutely determining the compo- sition of its radical. The water, therefore, is decomposed ; part of its hydrogen com- bines with one part of the cyanogen, and forms hydrocyanic acid; another part unites with the azote of the cyanogen, and forms ammonia ; the oxygen of the water forms carbonic acid with one part of the carbon of the cyanogen. The third acid results from some combination of the same kind, and there still remains some carbon and azote which could not be converted into any of those acids from a deficiency of oxygen, and which produces the brown deposit. Alkaline oxides produce similar effects, but much more quickly. Cyanogen, treated with a number of other oxides, metals, and combustible substances, afforded results not less curious to M. Vauquelin. The most interesting question that could be resolved was the inquiry whether prussian blue is a cyanuret or a hydro- cyanate ; thatis to say, whether it is a combination of oxide of jron with cyanogen, or rather with its hydro-acid. M. Vau- quelin having found that water impregnated with cyanogen can dissolve iron without changing it into prussian blue, and without the disengagement of any hydrogen gas, and that prussian blue was left im the undissolved portion; while hydrocyanic acid converts iron or its oxide into prussian blue without the help either of alkalies or of acids; he has concluded from hence, against the opinion of M. Gay-Lussac, that prussian blue is a hydrocyanate, and that when iron is exposed to water impreg- nated with cyanogen, there is not only formed in it cyanic acid, which dissolves a part of the iron, but also, and at the same time, hydrocyanic acid, which changes another part of the iron into prussian blue. He even establishes it as a general rule, that those metals which, like iron, decompose water at the ordinary temperature of the atmosphere, form hydrocyanates ; and that those metals which do not possess this power, as silver and quicksilver, form only cyanurets. t is well known that most acids are formed by the com- bination of oxygen with certain substances to which the name of radicals is given, and that the acid thus formed differs in its properties according as there enters into the combination a greater or less proportion of oxygen, and is called by a different name, to which modern chemists have given a certain regularity, indicating the degree of oxidizement by means of the termination. It is thus that azote produces, by successive additions of oxy- gen, nitrous gas, nitrous acid, nitric acid ; and we have mentioned in our Analyses for 1816 other combinations, which differ in their proportions, discovered by Messrs. Gay-Lussac and Dulong. 378 Proceedings of Philosophical Societies. [May, M. Thenard has lately made some experiments, from which it appears that many acids will admit the combination of much larger proportions of oxygen than those which have hitherto been regarded as their most highly oxygenized state. By care- fully dissolving super-oxidized barytes in nitric acid, and preci- pitating the barytes from it by sulphuric acid, the excess of oxygen remains united with the former acid, which, by this means, becomes oxygenized nitric acid. It may be concentrated by the means pointed out by M. Thenard, to such a degree that it will yield by heat 11 times its bulk of oxygen, and is then, according to the calculation of this experienced chemist, a com- bination of one volume of azote with three volumes of oxygen. The hydrochloric acid is oxygenized by the same means, and acquires some singular properties ; for on being applied to oxide of silver, water and a chloruret are formed, and the disengaged oxygen produces an effervescence as violent as when an acid is poured upon an alkaline carbonate. Sulphuric acid and fluoric acid may be oxygenized in the same manner, and all these acids may be again superoxygenized once or even oftener. M. Thenard has added in this manner to some as many as seven, and even 15 successive doses of oxygen. He has also forced hydrochloric acid to absorb a quantity of oxygen equal to 30 times its bulk. Nothing could equal the efiervescence that then took place on its coming in contact with oxide of silver. The earths and metallic oxides may be also superoxygenized by means of the acids thus surcharged with oxygen, and by similar processes. M. Thenard has even super- oxygenized water by pouring barytes water into superoxygenized sulphuric acid; the sulphuric acid united with the barytes, and ceded its excess of oxygen to the water. Water thus oxygen- ized freezes or evaporates in vacuo without losing its oxygen ; on the contrary, it becomes more concentrated, until it has absorbed from 40 to 50 times its volume of oxygen; but boiling carries off the oxygen; charcoal, silver, the oxide of silver, and those of several other metals, occasion it to be thrown off with a violent effervescence; and it is very singular that this rapid change of a considerable quantity of matter into a gaseous state, so far from producing any cold, heats the liquor very sensibly. M. Thenard supposes that electricity has some share in this phenomenon. It is known at present by the celebrated galvanic experiments of Sir Humphry Davy, that fixed alkalies are merely is oxides of extremely combustible metals; and by those of MM. Thenard and Gay-Lussac, that they can be reduced to the metallic state by means of charcoal and a very high temperature. We mentioned these grand discoveries in our Analysis for 1808. M. Vauquelin, having lately reduced antimony by alkaline fluxes, perceived that this metal put into water yielded a great quantity of hydrogen gas, and that the water became alkaline, —— 1820.] Royal Academy of Sciences. 379 Other metals, reduced in the same manner, produced the same appearances. From this he concludes, that a part of the alkali which he used combined in a metallic form during the operation with the antimony, and decomposed the water to return to the state of oxide ; but he has of course been also obliged to con- elude, that the presence of a metal is favourable to the reduction of the alkali, as otherwise it would not have taken the metallic form in so low a temperature. We mentioned last year some experiments of MM. Chevillot and Edouard upon that singular combination of manganese and otash which is called the mineral cameleon, upon account of the facility with which its colour may be changed several times successively. These young chemists have continued their labours, and have discovered that soda, barytes, and strontian, will yield different sorts of cameleons, by uniting, like potash, with the oxide of manganese and absorbing the oxygen from it ; but, confining their principal attention to the species of cameleon formed by potash, in which the alkali is perfectly neutral, and which is of a fine red colour, they have found that those bodies which are very combustible act very energetically upon it, that they decom- pose it, and frequently take fire together with a strong detona- tion: phosphorus even produces a detonation by simple contact. On the other hand, this red cameleon, exposed to fire, is decom- posed, and yields oxygen, black oxide of manganese, and green cameleon, in which potash is in excess. They conclude from these facts, that in the formation of the cameleon, the result of the intervention of the oxygen is a further oxidizement of the manganese, and the conversion of it into a true acid; so that the cameleon is a manganesiate of potash. The red cameleon in particular, being a perfectly neutral manga- nesiate, and the green, a manganesiate with an excess of alkali. Still, however, they have not been able to insulate the acid whose existence they admit; but they have made numerous experiments which they imagine to confirm the opinion they pub- lished last year, that the green cameleon only differed from the red by having more alkali in its composition. When acids are poured upon the green cameleon, or an alkali upon the red, they are equally changed from one colour to the other ; even boiling and agitation are sufficient to disengage the excess of potash in the green cameleon, and to change it into red. Many acids also, when used in excess, decompose the cameleon entirely, by taking the potash from it, disengaging the oxygen, and precipitating the manganese in the state of black oxide. Sugar, gums, and several other substances, capable of taking away the oxygen, also decompose the cameleon; and an exposure to the air produces a similar effect, which these authors ascribe to the foreign particles floating in the atmosphere, and 380 Proceedings of Philosophical Societies. [May, which, falling into the solution, take away a portion of the oxygen that is essential to its existence. Cobalt and nickel are two semimetals which it is very difficult to obtain in a state of purity, and still more difficult to separate entirely from one another ; nevertheless this purification is neces- sary for an exact determination of their respective properties. M. Laugier having tried the newest methods that have been published as proper to obtain this object, has found in nickel unequivocal traces of cobalt. In order to get rid of them, he dissolved the mixed metal in ammonia, and precipitated it by oxalic acid; he then redissolved the oxalate of nickel and cobalt obtained by this operation in concentrated ammonia, and exposed the solution to the air. As the ammonia exhaled, oxalate of nickel mixed with ammonia was deposited. The nickel was entirely separated from the liquid by repeated crys- tallizations; so that there remained only a combination of oxalate of cobalt and ammonia, which was easily reduced. The small quantity of cobalt that remained in the nickel that was precipitated was separated by several successive solutions in ammonia; so that one and the same operation yielded both metals in a state of purity. Sugar of milk, treated with nitric acid, yields an acid, origi- nally discovered by Scheele, and which has been since called the mucic acid, because it is also produced by the action of nitric acid upon gums and mucilages. When this acid is exposed to heat, a brown saline matter is sublimed, of-a strong smell, soluble in water and alcohol, and burning with a flame upon lighted charcoal. Trommsdorf, who particularly examined this sublimed substance, Conceived he had found in it succinic acid, pyrotartaric and acetic acids, and several other substances ; but M. Houton-Labillardiere perceiving, upon the reading of Trommsdorf’s essay, that he attributed to the succinic acid very different characters from those that this acid really possesses, thought proper to resume the research. He has read a memoir to the Academy, in which he proves that this pretended succinic acid is a new acid, to which he gives the name of pyromucic acid. When it is cleared from the oil and acetic acid with which it is mixed, it easily crystal- lizes, and is white, scentless, of a strong acid taste; it melts at 130 centigrade degrees (266° Fahr.) is volatilized at a little above that temperature, does not attract moisture, dissolves much more abundantly in boiling water than in cold; and upon its beng resolved into its constituent parts, there were obtained from it about nine volumes of the vapour of carbon, three of hydrogen, and two of oxygen. M. Houton-Labillardiere carefully describes the combinations of this acid with different salifiable bases, and all the appearances that he relates support the assertion of this young and skilful chemist. 1920.) Royal Academy of Sciences. 38h M. Chevreul has made new and important additions to his researches upon fatty bodies, with which we have already several times entertained our readers. Having found that the matter of ~ biliary calculi, which he calls cholesterine, does not form a soap with the alkalies—a circumstance which distinguishes it com- pletely from fats ; he thought he had also found, that spermaceti, to which he gave the name of céfine, was reduced by the action of alkalies into an acid analogous to one of those two acids that the alkalies produced from fats; namely, into that which he called margaric acid, but that the acid of spermaceti had a much smaller capacity of saturation. He, therefore, judged it necessary to give this acid a peculiar name, and called it ceéic acid. A continuation of these experiments has, however, convinced him that this acid is in fact only margaric acid, whose properties have been altered by some remains of a fatty matter not of an acid nature. But dolphin oil, when treated by M. Chevreul’s method ; that is to say, converted into soap by means of the alkalies, afforded, besides the two acids yielded by fatty sub- stances, a third sort of acid, which-he calls the de/phinic, but which is not yielded by common fish-oil. It must be noticed that oxygen is not found to be contained in these new ternary acids prepared from fats, and that they are, in respect to the common vegetable acids, the acetic acid, the oxalic, &c. the same as in the mineral kingdom, the hydro-acids of Sir H. Davy are, in respect to the old and well- known mineral acids, the mitric acid, the sulphuric, &c. Cochineal, that singular insect, which, on account of the colouring matter that it yields, is become such an important article im commerce, not having been studied as yet by chemists with that attention which it deserved, MM. Pelletier and Caventou have made it the object of their experiments. They have found that the very remarkable colouring matter which composes the principal part of it, is mixed witha peculiar animal matter, a fat like common fat, and with different sorts of salts. The fat having been separated by ether, and the residuum treated with boiling alcohol, they either allowed the alcohol to cool, or gently evaporated it, and by this means they obtained the colouring matter, but still mixed with a little fat and animal matter ; these were separated from it by again dissolving it in cold alcohol, which left the animal matter untouched, and b mixing the solution with ether, and thus precipitating the colour- ing matter in a state of great purity. It is well known that this colouring matter is of a most beautiful red colour, and the chemists of whom we are speaking, give it the name of car- mine (carminium). It melts at 50° (122° Fahr.) becomes puffy, and is decomposed, but does not yield ammonia. It is very soluble in water, slightly in alcohol, and not at all in ether, unless by the intermediation of fat. Acids change it from crimson, 382 Proceedings of Philosophical Societies. [May, first to bright red, and then to yellow: alkalies, and generally speaking all protoxides, turn it violet; alumine takes it from water. These experiments explain many of the processes in the art of dyeing and colour making, and particularly they explain what happens in dyeing scarlet, and in the manufacture of carmine and lake. Lake is composed of carminium and alumine ; it has the proper colour of carminium ; that is to say, crimson. Carmine itself is a triple compound of an animal matter, carminium, and an acid which enlivens the colour ; the action of muriatic acid in chang- ing the crimson colour of cochineal into a fine scarlet is similar. METEOROLOGY. The most apparent causes of atmospheric phenomena, such as the density of the air, its moisture, its heat, and its electricity, appear to depend principally upon the action of the sun: neyer- theless the irregularity of their effects m our climates are sufficient to show that there exists influences of a different kind, and that. they are complicated with causes still unknown: it is this complication which renders meteorology, even at. present, the branch of the physical sciences which has made the smallest approach to that degree of certainty which is necessary to its being considered as a real science. M. Humboldt remarks, that if any hope exists that the laws of meteorology can ever be discovered, it must be by studying it in those climates where the phenomena are of the most simple and the most regular nature ; and the torrid zone must, on these grounds, attract the principal notice of observers. It is only between the tropies that it has been possible to determine the laws which regulate the small hourly variation of the barometer ; it is in the torrid zone that dry and wet seasons, and that the direction of the winds peculiar to each season, are submitted to invariable laws. M. Humboldt has paid much attention to the relation between the declination of the sun and the commencement of the rainy season in the north part of the torrid zone. In proportion as the sun approaches the parallel of any place, the northern breezes are changed for calms, or south easterly winds. The transparency of the airis diminished, the unequal refrangibility of its strata causes those stars to twinkle which are 20° above the horizon. The vapours scon collect in clouds ; positive electricity is no longer constantly to be found in the lower part of the atmosphere, thunder is heard during the day, heavy rain succeeds, the calm of night is only interrupted by gales from the south-east. M. Humboldt explains these appearances by the greater or less inequality between this part of the torrid zone and the neigh- bourimg part of the temperate zone. When the sun is to the 1820.] Royal Academy of Sciences. 383 south of the equator, it is winter in the northern hemisphere. The air of the temperate zone is then as different as it can be from that of the torrid zone. There flows into the latter a con- “stant, cool, and uniform breeze, which carries the heated and moist air into the higher regions, from whence it flows back towards the same temperate zone, reestablishes the equilibrium, and deposits its moisture there ; so that the mean heat is always 5° or 6° less in the dry season than in the rainy ; but the south- east winds do not act like those of the north ; because they come from a hemisphere which contains much more water, and in which the upper current of air is not dispersed in the same manner as in the northern hemisphere. M. Moreau de Jonnes has communicated some details, ex- tracted from his correspondence, relative to the hurricane that caused so much damage in the Caribbee islands the 21st of last September. It was preceded by a dead calm, the wind shifted from north to north-west, and it was in this point that it blew with violence. M. de Jonnes remarks upon this subject, that in the preceding year the hurricane of the 20th of October came from the south west; and that there exists a space of 90° between these two points, from south to north, from whence the wind never blows. The agitation of the air was followed by a great swell of the sea, which caused the shipping to drive; yet no extraordinary movement was observed in the barometer. It is remarked, with some degree of sorrow, that the effect usually attributed to hurricanes, of purifying the air of the countries they devastate, was not verified upon this occasion, for the yellow fever did not cease to commit its usual ravages. The same observer has also given some notices respecting the earthquakes which have been felt this year in the Caribbee Islands ; and which have had this peculiarity, that they have affected a kind of periodical recurrence. Eight of these earth- quakes were felt from December to May; one every month, except in April, in which month there were two; and all of them took place in the night between nine o’clock and eleven. MINERALOGY AND GEOLOGY. M. Beudant continues to enrich crystallography with re- searches equally new and interesting. We saw last year, by his experiments, how a saline principle of a certain kind sometimes impressed its crystalline form upon a mixture in which it did not by any means form the greatest part. He has occupied himself this year with a question that is not less important in respect to the knowledge of crystals; namely, to determine the causes which occasion a saline substance, whose ~ primitive molecules and nucleus have a constant form, to be dis- guised, by means of the accumulation of its molecules according to different laws, with so many and so various secondary forms that their number is sometimes astonishing. “pve 384 Proceedings of Philosophical Societies. [May, Having remarked that the secondary forms of a substance are’ most commonly the same in any one mine or place where it is found associated with other minerals under similar circumstances ; he judged that the secondary forms arise from the medium in which the crystallization takes place. It has been known for a long time, from the experiments of Romé de Lille, and those of Fourcroy and M. Vauquelin, that the presence of urea occasions common salt to take an octahe- dral form, although in pure water it crystallizes in cubes, similar to its constituent molecules. The same substance produces an opposite effect upon muriate of ammonia, which crystallizes in octahedrons in pure water ; while urea causes it to crystallize in cubes. A very slight excess or deficiency of base in alum causes it to assume either cubical or octahedral secondary forms ; and these forms are so truly secondary that an octahedral crystal of alum immerged in a solution which is richer in respect to its basis, becomes enveloped with crystalline layers, which cause it to assume at length the form of a cube. Setting out from these facts, M. Beudant treats the question at full length, and has submitted the crystallization of salts to experiments made under every circumstance that he believed capable of exerting any influence upon it ; namely, 1. General and external circumstances ; such as heat, weight of the atmosphere, greater or less rapidity of evaporation, bulk ef the solution, form of vessels, &c. 2. Mechanical mixtures which foul the solution, whether simply suspended in the state of an incoherent precipitate, or in that of a gelatinous deposit. 3. What he denommates chemical mixtures existing in one and the same sohition. 4, Lastly, variations in the proportion of the constituent prin- ciples of the crystallized substance. The circumstances of the first kind do not exercise any other action than what regards the size and perfection of the crystals. The case is even the same, as to any small portion of matter which remains in permanent suspension in the liquid ; but this cannot be said in respect to precipitates and chemical mixtures. Crystals formed in the midst of an incoherent precipitate, deposited like mud at the bottom of a liquid, always take up a more or less considerable portion of the molecules of this precipi- tate, and by this admixture they usually lose all those small addi- tional facets which would otherwise modify their predominant form. Thus the crystalline form acquires greater simplicity when it should apparently become more complicated ; at the same time the substances which would otherwise have yielded simple crys- tals still continue to yield them, and they do not receive any modification. In a gelatinous deposit, crystals are rarely found in groups, 1820.] Royal Academy of Sciences. 385 but almost always single, and of aremarkable sharpness and recu- larity of form, and they do not undergo any variations, but those which may result from the chemical action of the substance form- ing the deposit. The variations that take place in crystals formed in a chemical mixture ; that is to say, in a solution of another substance, are very numerous, even when this substance cannot be united with them. The above-mentioned phenomena are repeated in differ- ent forms: common salt crystallized in a solution of borax acquires truncations at the solid angles of its cubes; and alum crystallized in muriatic acid takes a form which M. Beudant has never been able to obtain in any other manner. If the foreign substance dissolved in the liquid can be united in any proportion whatever with the crystal of another substance that is formed in it ; and nevertheless the crystal, by its superior energy, determines the form of the constituent molecule, as we saw last year in the case of sulphate of iron, the matter in the solution will exercise in its turn some influence upon the second- ary form of the crystal, and this- influence usually consists in simplifying it, and causing the additional facets to disappear. hus 30 or 40 per cent. of sulphate of copper may be united to the rhomboidal crystallization of sulphate of iron, but it reduces this sulphate to a pure rhomboid without any truncation either of the angles or of the edges. A small portion of acetate of copper reduces sulphate of iron to the same simple rhomboidal form, notwithstanding that this formis so disposed to become complicated with additional surfaces. Other mixtures simplify in aless degree : thus the sulphate of alumine brings that of iron to a rhomboid with the lateral angles only truncated, or what M. Hatiy calls his variété unitaire ; and whenever this variety of green vitriol is found in the market, where it is very common, we may be sure, according to M. Beudant, that it contains alumine. Lastly, the different proportions between the base and the acid, or, in double salts, between the two bases, produce very sensible effects upon the secondary forms, without altering the primitive form in the least. This has been already exemplified in Beer to alum, and M. Beudant has verified it in many other salts. The author of these researches has made some ingenious appli- cations of these facts to the phenomena afforded by different crystalline mineral substances, upon which direct experiments cannot, in the present state of the science, be made; and he has exhibited some striking analogies; thus natural crystals mixed with foreign substances are in general more simple than others, as is shown in a specimen of axinite, or violet schorl, of Dauphiné, one extremity of which, being mixed with chlorite, is reduced to its primitive form; while the other end, which is pure, is varied by many facets produced by different decrements. Vou, XV. N° V. 2B 386 Proceedings of Philosophical Societies. {May, There is found rather abundantly in a ravine of the Mount d’Or, in Auvergne, fragments of a breccia, the hardness and other external characters of which having led to the supposition of its being of a siliceous nature, mineralogists did not pay much attention to it, except on account of some particles of sulphur which it sometimes contains im small cavities. M. Cordier, having submitted this breccia to different trials, found that it yielded by heat a notable proportion of sulphuric acid, and upon this important indication he proceeded to make a complete analysis of it, by which he found that this stone con- tained about 28 per cent. of silica, 27 of sulphuric acid, 31 of alumine, 6 of potash, and a little water and iron. These are very nearly the same ingredients as are found in the celebrated ore of Tolfa, which yields Roman alum. In reality, upon treating this breccia from the Mont d’Or, in the same manner as is practised at Tolfa; that is to say, by breaking it, roasting, and exposing it to a moist air, from 10 to 20 per cent. of very pure alum was obtained from it; and this breccia even yielded alum without being roasted, but merely by exposure in a damp situation. It is probable, from the researches made upon the spot by M. Ramond, that, with some pains, the beds from which the fragments scattered in the ravines were detached, may be disco- vered; and that quarries may be opened, the working of which cannot but be of advantage. M. Cordier regards these sorts of stones as a mineralogical species, consisting essentially of sulphuric acid, alumine, and potash. ‘The silica found in it is not essential for quarries of a stone not containing any silica, but all the other constituent principles exist at Montrone, in Tuscany, and yield the same products as that at Tolfa. Those varieties of this species in which silica enters, are easily distinguished by the jelly they form when they are treated in succession with caustic potash and hydrochloric acid diluted with water. M. Cordier reduces to this species several volcanic stones, hitherto vaguely designated by geologists by the general deno- mination of altered lava. Some country people in the department of the Lot, allured by the hope of finding pretended treasures, which are said to have been formerly buried by the English in certain caves in the neighbour- hood of Breugue, have penetrated into these cavities, and having dug into and enlarged*some crevices which they found at the bottom of them, they have discovered a deposition of bones, some of which belong to horses, others to that species of rhino- ceros, of which so large a quantity of fossil bones have been found in Siberia, Germany, and England; others again to a species of cervus not at present known to exist, and the horns of which have some slight analogy with those of a young rein-deer. Guettard found a great number of these horns in the neigh- bourhood of Etampe. 1820.] Royal Academy of Sciences. 387 These important witnesses of the revolutions of our continent have been collected by M. Delpont, Procureur du Roi at Figeac, and presented to the Academy by M. Cuvier. They are depo- sited in the King’s cabinet. M. Palissot de Beauvois has acquainted the Academy with a rather singular geological appearance, which he observed in the county of Rowan, in North Carolina. There is found in the middle of a hill formed of very fine sand mixed with small quartz- ose stones, and with numerous pieces of silver-coloured mica, a vein of stones so regularly placed that the inhabitants who, for a long time, have noticed the appearance, give it the name of the natural wall; and some naturalists have even maintained that it was a true wall, which might have been constructed in very remote ages by some people now unknown. ‘The stones have generally four faces, are narrower at one of their ends, and have a small notch below their top. They are ranged horizontally. The kind of wall which they form is about 18 inches thick, its height in the place where it 1s uncovered is from six to nine feet, but upon digging into the ground, it has been followed to 12 and 18 feet deep, and it is already known to extend 300 feet, and even more, in length. A kind of argillaceous cement fills the intervals between the stones, and coats them externally ; each of the’ stones is also covered with a layer of ochreous sandy earth. M. de Beauvois has brought some of these stones to France, and upon being examined by the mineralogists of the Aca- demy, they appeared to possess the characters of basalts ; but as there has not as yet been found any traces of basalts or of volca- noes in the United States, and as the place where this wall is found is, generally speaking, of a primitive nature, it is possible that this pretended wall is nothing but a bed of trap; an amphi- bolic rock very similar to certain kinds of basalts. We spoke in 1816 of the labours undertaken by M. Moreau de Jonnes to determine the geology of the Caribbee Islands, of the general ideas he had adopted on this subject, and of the particular description relative to Martinique and Guadaloupe, that he had presented to the Academy. He has continued the arrangement of his labours, and has read a paper upon the Vau- clan, one of the most remarkable mountains in Martinique, not that it is the highest, but because it serves as a guide, and announces this island to navigators. It has not the form of a cone, hollowed at its top, but that ofa prism resting on its side, or of an immense basaltic ridge; and M. de Jonnes considers it as part of the circuit and of the edge of a very large crater, the whole of which he thinks he has traced. The bottom of this crater is at present a valley not only fertile, but well cultivated. The same author has given a geological description of Guada- loupe. He finds that the western island, in which there exists a solfatara in an active state, and the surface of which is about 67 square leagues, owes its origin to eruptions from four large subs marine yolcanoes, and that the eastern island, commonly called 2B 2 388 | Scientific Intelligence. [May, Grande Ferre, is formed of a volcanic basis, covered with a thick bed of shell limestone. At Martinique, the eastern quarters are also covered with beds of marine limestone, either shelly or coralline. The second part of La Richesse Minéralle of M. Héron de Villefosse, which was presented in manuscript to the Academy in 1816, has appeared this year in print, with an atlas. This work has justified the judgment that the commission passed upon it, and is become the indispensable guide of all those who are employed in the administration of mines, and in the works belonging to them. , (To be continued.) ARTICLE XIII. SCIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS CONNECTED WITH SCIENCE. I. Succinic Acid. Dr. John, of Berlin, announces, that he has obtained succinic acid by the following process: ; Two pounds of bread, a pound and a half of honey, as much of the fruit of the ceratonia siliqua, two pints of vinegar, as much spirits, and 28 pints of water, were treated in such a way as to obtain a liquid proper for undergoing the acetous fermentation. The vinegar produced was saturated with lime, and the acetate evaporated to dryness. ‘Twenty-four ounces of this salt were triturated with an ounce of peroxide of manganese ; the mixture was put into a retort, and subjected to distillation, after having been mixed with 16 ounces of sulphuric acid diluted with 13 ounces of water. When no more acid came over, the receiver was changed, and the fire augmented. A sublimate.then condensed in the neck of the retort which possessed the characters of suc- cinic acid. When rectified, it crystallized in white flexible needles, and weighed two drachms. John repeated this process two or three times, and always obtained succinic acid. The fruit of the ceratonia siliqua did not yield any succinic acid when subjected to analysis. Hence he is of opinion, that the succinic acid obtained was formed dur- ing the process. Il. Animal Charcoal. Dobereiner has analyzed animal charcoal by heating it with peroxide of copper, and informs us that its constituents are : BRONTE G5 Sons olin: cia tesa oo ae 34°2 PV ROES 6 5 wre haybie «isis fergie Gs a aL 1820.] Scientific Intelligence. 389 This approaches very nearly to six atoms carbon and one atom azote ; for 6 atoms carbon. ........ 1 ALON. AZOLE Gems «o/s ciccches 4:50 1:75 Now 4°5 : 1:75 :: 34:2 : 13:3. If we suppose this analysis correct, the equivalent number for animal charcoal will be 6°25, or some multiple of it. We are already acquainted with two other compounds of carbon and azote, pointed out and analyzed by Gay-Lussac. 1. Azoturet of carbon composed of three atoms carbon and one atom azote. 2. Cyanogen composed of two atoms carbon and one atom azote. III. Antidote for Vegetable Poisons. M. Drapiez has ascertained by numerous experiments that the fruit of the Fewillea cordifolia is a powerful antidote against vegetable poisons. This opinion has been long maintained by naturalists, but I am not aware that it was ever before verified by experiments made on purpose in any part of Europe. M. Drapiez poisoned dogs with the rhus toxicodendron, hemlock, and nux vomica. All those that were left to the effects of the poison, died ; but those to whom the fruit of the fewillea cordi- folia was administered, recovered completely after a short illness. To see whether this antidote would act in the same way, when applied externally to wounds into which vegetable poisons had been introduced, he took two arrows which had been dipped in the juice of manchenille, and slightly wounded with them two young cats. To the one of these, he applied a poultice, com- posed of the fruit of the fewillea cordifolia, while the other was _ left without any application. The former suffered no other inconvenience, except from the wound, which speedily healed ; while the other, ina short time, fell into convulsions and died. It would appear from these experiments, that the opinion entertained of the virtues of this fruit in the countries where it is produced is well founded. It would deserve in consequence to be introduced into our pharmacopceias as an important medicine ; but it is necessary to know that it loses its virtues, if kept longer than two years after it has been gathered. IV. Nitrate of Silver, M. Brandenbourg has pointed out an economical method of separating silver from copper, or of making»pure nitrate of silver, from an alloy of silver and copper, which is an object of some importance to practical chemists. His method is as follows: He dissolves the alloy of silver and copper in nitric acid, and evaporates the liquid to dryness in a glass vessel. ‘The salt is then put into an iron spoon, and exposed to a moderate heat, keeping the salt in a state of fusion till all ebullition is at an end, 390 Scientifie Intelligence. [May, It is then poured upon an oiled slab. To determine whether all the nitrate of copper has been converted into black oxide, alittle of the salt is dissolved in water, and the solution is tested by ammonia. Ifthe liquid, which ought to have been at first trans- parent and colourless, does not acquire the least tint of blue, we may conclude that it contains ne copper. If there be still found traces of copper in the salt, we continue the fusion for some seconds longer. The salt by this treatment becomes black from the mixture of peroxide of copper with the nitrate of silver. To separate them, we have only to digest the salt in pure water. The nitrate of silver is dissolved, and constitutes a transparent and colourless solution, while the peroxide of copper remains behind. We have then only to evaporate the solution to obtain the nitrate of silver in the state of crystals. V. Gluten of Wheat. M. Taddey, an Italian chemist, has lately ascertained that the gluten of wheat may be decomposed into two principles, which he has distinguished by the names, g/iadine (from yaa, gluten), and zzmome (from guyyuy, ferment). They are obtained in a sepa- rate state by kneading the fresh gluten in successive portions of alcohol, as long as that liquid continues to become milky, when diluted with water. The alcohol solutions being set aside gra+ dually deposit a whitish matter consisting of small filaments of gluten, and become perfectly transparent. Being now leit to slow evaporation, the gliadine remains behind, of the consistence of honey, and mixed with a little yellow resinous matter, from which it may be freed by digestion in sulphuric ether, in which gliadine is not sensibly soluble. The portion of the gluten not dissolved by the alcohol is the z¢mome. VI. Properties of Ghadine. When dry, it has a straw-yellow colour, slightly transparent, and in thin plates, brittle, having a slight smeli, similar to that of honeycomb, and, when slightly heated, giving out an odour similar to that of boiled apples. In the mouth, it becomes adhe- sive, and has a sweetish and balsamic taste. It is pretty soluble in boiling alcohol, which loses its transparence in proportion as it cools, and then retains only a small quantity in solution. It forms a kind of varnish in those bodies to which it is ‘applied. It softens, but does not dissolve in cold distilled water. Ata boiling heat it is converted into froth, and the liquid remains slightly milky. It is specifically heavier than water. The alcoholic solution of gliadine becomes milky, when mixed with water, and is precipitated in white flocks by the alkaline carbonates. Itis scarcely affected by the mineral and vegetable acids. Dry gliadine dissolves in caustic alkalies and in acids. It swells upon red-hot coals, and then contracts in the manner of animal substances. It burns with a pretty lively flame, and 7 1820.] Scientific Intelligence. 391 leaves behind it a light, spongy charcoal, difficult to incinerate. Gliadine, in some respects, approaches the properties of resins ; but“difters from them in being insoluble in sulphuric ether. It is very sensibly affected by the infusion of nutgalls. Itis capable of itself of undergoing a slow fermentation, and produces fer- mentation in saccharine substances. VU. Properties of Zimome. The gluten, thus treated by alcohol, is reduced to the third part of its former bulk. This diminution is owing not mereiy to the loss of the gliadine, but hkewise to that of water. The residue is zimome, which may be obtained pure by boiling it repeatedly in alcohol, or by digesting it in repeated portions of that liquid cold, till it no longer gives out any gliadine. Zimome thus purified has the form of small globules, or consti- tutes a shapeless mass, which is hard, tough, destitute of cohe- sion, and of an ash-white colour. When washed in water, it recovers part of its viscosity, and becomes quickly brown when Jeft in contact of the air. It is specifically heavier than water. Its mode of fermenting is no-longer that of gluten ; for when it putrefies, it exhales a fetid urinous odour. It dissolves completely im vinegar and in the mwmeral acids at a boiling temperature, With caustic potash it combines and forms a kind of soap. When put into lime-water, or into the solutions of the alkaline carbonates, it becomes harder, and assumes a new appearance without dissolving. When thrown upon red-hot coals, it exhales an odour similar to that of burning hair or hoofs, and burns with flame. Zimome is to be found in various parts of vegetables, It produces various kinds of fermentation, according tv the nature of the substance with which it comes in contact. VIE. Prussic Acid in Consumptions. Most of our readers are aware that M. Magendie some time ago proposed prussic acid as a remedy in incipient consumption, In a disease of so desperate a nature, and which has hitherto bafiled all the efforts of medical men, every new proposal is entitled to attention. This induces me to lay M. Magendie’s formula before my medical readers. He mixes one part of pure prussic acid (or hydrocyanic acid) prepared according to Gay-Lussac’s method, with 8-5 parts of water by weight. To this mixture he gives the name of medi- cinal prussic acid. The state in which this substance is given to patients will be seen by the following formula : Ke Medicinal prussie acid.. 1 gros, or 59-00 ers. troy Distilled water ,.......1 lb, or 7560-00 ers, Pure sugar. .......... 1402. or 70875 grs. Mix these ingredients, and let the patient take a table spoon- t ul every morning and evening, 392 Scientific Intelligence. [May, 1X. Camphor. The peculiar characters of camphor are well known to chemists. Its great volatility, its strong smell, its fusibility when heated, its solubility in nitric acid, and in alcohol. In some respects it resembles the volatile oils ; but the nondecomposition of it by nitric acid, except when we employ a great deal of acid, and assist the action by heat, sufficiently distinguishes it from these bodies. It melts, when heated to 288°, and boils at the temperature of 400°. I had the curiosity to analyze it by passing it slowly through red-hot peroxide of copper. By this process it was converted into carbonic acid and water. The first of these I collected over mercury and measured, while the second was intercepted by means of muriate of lime, and the quantity of it was made known by the increased weight of the salt. One grain of camphor, when thus treated, yielded 5-837 cubic inches of carbonic acid gas under the mean temperature and pressure, and 1:3 gr. of water. Hence the constituents of camphor are : Carbon in carbonic acid.........-... 0:738 Hydrogen in water .....+e+-seeeeee 0-144 Oxygen (to make up the deficiency) .. 0-118 1:000 This approaches very nearly to 81 atoms carbon .... 10 atoms hydrogen .. 1 atom oxygen..... O(a « ehotel 1-260. ...... 14:49 10007 =... DEOU 8°625 100-00 X. Prussiate of Iron. The nature of prussiate of iron not being hitherto determined in a satisfactory manner, I made some time ago the following experiments on it, which appear to me to explain its composition pretty completely. A quantity of pernitrate of iron was preci- pitated by prussiate of potash, and the deep blue precipitate was collected on a filter, well washed, and dried in a temperature not above 150°. It is well known that this salt catches fire and burns with the emission of a great quantity of ammonia, when exposed to a heat not greatly exceeding 212°, It cannot, there- fore, be completely freed from water by heat ; but as there is no great difficulty in determining the weight of the peroxide of iron, and of the ferrochyazic acid which the powder contains, I consider the presence of'a little moisture as of no great conse- quence, 1. To determine the quantity of peroxide of ivon, I digested 20 gr. of the prussiate of iron in potash ley diluted with water over a sand-bath for 24 hours. The liquid was then drawn off, and the red sediment carefully washed and dried. It weighed 7°56 gr. and was pure peroxide of iron. Mt a 1820.] Scientific Intelligence. 393 2. Being thus acquainted with the weight of peroxide of iron in 20 gr. of the powder, I calculated how much ferrochyazic acid was requisite to saturate this quantity of iron; and how much potash would be just sufficient to decompose 20 gr. of prussiate of iron. This quantity of potash, together with the 20 gr. of the prussiate of iron and a sufficient quantity of water, were put into a phial, and digested on the sand-bath for 24 hours. The whole was then thrown on a filter, and the peroxide of iron remaining on the filter was washed quite clean with distilled water. ‘The liquid which passed through the filter had a yellow colour, and the taste and properties of a solution of prussiate of potash. Being evaporated to dryness, and exposed to a heat of about 212°, there remained 19-3 ers. of pure prus- siate of potash. Now 19:3 grs. of prussiate of potash dried at the temperature of 212° contain 10-2 gr. of ferrochyazic acid. This of consequence is the quantity of ferrochyazic acid contained in the 20 gr. of prussiate of iron which I examined. From the preceding experiments, it follows that prussiate of iron is composed of Ferrochyazic acid...... 10°20 “ie prep tO 6D Peroxide of iron. ...... OOM Ae we Oto Water iii.c'sb sve PPG Ale DA yz teal Wied 20:00 100-0 Now if we consider (with Mr. Porrett) the weight of an atom of ferrochyazic acid as 6°75, and that of an integrant particle of peroxide of iron as 5, in that case prussiate of iron will be a compound of one atom ferrochyazic acid and one atom of per- oxide of iron. If we were to suppose the weight of an atom of peroxide of iron to be 10, then in that case the salt would be a compound of two atoms acid + one atom peroxide. But I am disposed to embrace the first alternative in consequence of the following fact which is easily verified. Dissolve protosulphate of iron in water, and mix the solution with some sulphuretted hydrogen gas. Then drop into it prus- siate of potash. A white powder is thrown down, which is a neutral protoferrochyazate of iron, or a compound of an atom of ferrochyazic acid and an atom of protoxide ofiron. Expose this salt while moist to the air, and it is gradually converted into perferrochyazate of iron (or prussian blue) simply by the absorp- tion of oxygen. It is well known to the manufacturers of prussian blue that the pigment is at first of a dirty pale blue, and that it acquires its intense blue colour by long and laborious washing in water. The reason of this is, that a considerable proportion of the salt made at first by them is in the state of protochyazate of iron, and it slowly becomes perchyazate by absorbing oxygen from the atmosphere. If we employ the pernitrate of iron instead of the sulphate, we form prussian blue, at once possessed of the requi- 394 Scientific Intelligence. [May, site beauty and intensity of colour. Manufacturers would probably shorten their process considerably by dissolving the sulphate of iron in water some months before they use it, and by keeping the solutions in shallow vessels exposed to the action of the atmosphere. XI. Hydrocyanate of Ammonia. When prussiate of iron (prussian blue) is exposed to a red heat in a copper tube, and the products received in glass jars standing over mercury, the glass jar becomes coated with trans- parent crystals, having the smell of hydrocyanic acid, and readily soluble in water. When a drop of sulphuric acid is let fall into a concentrated solution of these crystals, an effervescence takes place, and a strong smell of hydrocyanic acid exhales. When * some soda is mixed with the aqueous solution of these crystals and heat applied, a strong smell of ammonia is perceived. Hence I consider the crystals as hydrocyanate of ammonia. The efiect produced by the solution of these crystals upon different metalline solutions was as follows. It precipitated 1. Permuriate of iron, Yellow. ; 2. Sulphate of copper, isin, with a light shade of ue. 3. Nitrate of lead, White, precipitate redissolved by nitric acid. 4. Nitrate of mercury, White, ditto. 5. Corrosive sublimate, White, redissolved by agitation. 6. Sulphate of zinc, White, slight. 7. Muriate of manganese, Ditto, ditto. 8. Nitrate of silver, White, redissolved by agitation. 9. Sulphate of nickel, Greenish, slight. 10. Sulphate of cobalt, Reddish, ditto. These precipitates do not correspond with those indicated by Scheele ; but he made use of hydrocyanic acid; not hydrocya- nate of ammonia, which is probably the cause of the difference. XII. Kilkenny Coal. In the paper which I published last summer on the different species of pit-coal, I was obliged to leave out Kilkenny coal for want of the requisite specimens. I have been lately enabled, by the kindness of a friend, to make up that deficiency. I shall state here the result of my trials to determine the composition of this species of coal. Its specific gravity was 1:4354. One hundred grains of it, when burned completely in a muffle, left four grains of a reddish-brown light earth, not in the least acted on by acids. One hundred grains, when heated for several hours in a covered platinum crucible left 86°7 grs. of coal not in the least altered in its appearance. Hence the loss of weight was proba- bly owing not to the dissipation of any volatile matter from the ——E 1820.] Scientific Intelligence. 395 coal, but to the combustion of part of it from the long continued action of the heat, as the crucible, though covered with a lid, was not impervious to air. } One grain of this coal, when mixed with peroxide of copper, and exposed to a strong red heat, formed 7-06 cubic inches of carbonic acid gas; "and no water whatever nor azotic gas was evolved. Now seven cubic inches of carbonic acid gas contain 0°893 gr. of carbon. Hence the grain of coal consisted of RERTUON 5.c0'e <0 so 0:893 RRS oa tele sin 0-040 Deficiency. .... 0°067 which must have been oxygen, Now 0°893 gr. carbon and 0:067 gr. oxygen, when converted into volumes, are very nearly 7 cubic inches carbon, 0-2 cubic inch oxygen. Which is equivalent to 35 atoms carbon. ...... = 26°25 2 atoms oxygen. ...... = 2°00 28°25 So that Kilkenny coal differs essentially in its composition from every other species hitherto examined. XIII. Geographical Positions on the Coast of Dalmatia determined by Capt. G. LH. Smyth. Latitude. Long. E. Ferro. * Corfu Fort Alexandre sur Vido..39° 38’ 5/”137° 35’ 23” + Cape Bianco (Corfu).......... 39 20 50 7 46 35 + Cape Drasti (Corfu) ...... aE a 39 47 -10 187-21" 45 Se Merierit (1616) Vege recess wales ts 39 662 °50 7 14 55 + Fano (west point)....... oe 39. 50 2036 59 35 + Port Palermo (the castle) ...... 40 2 55 87 27 55 sa eEAGa DIARCR oie cansncecer e400 8 45:37 17 35 Sa WAMU ODTEA ie tio hie! alle eld, ediin oe 40 19 12/87 0O 20 * Saseno (isle, on the hill)........ 40 29 10 (86 53 57 + Aulona (Douanne) ............ AQ 2h). SS BP 2 i ee — Pointe Samana (centre)........ 40 48 55 (36 57 22 — Cape Lachi (tower). ........4. 41 10 1087 5° °5 + Durazzo (the highest marabut)..41 17 3237 6 20 PREM MMIOIE AM | sin's'n bie’ o BS whine als a AVA 23 5 (oT eo ae Bo me Cope rodont. ... ss 2,2 bsp de. a. 41 37 35 387 7° 65 — St. Jouan di Medua. .......... 41 48 2087 8&8 45 — Duleigno (Marabut)........... 41.63 50 86 60. 25 Se AMV ATT (POUL) 6 0 ciolsise ¢ vce o% 42 2°17 (36 46 10 * Budna (St. Nicolas)..... nda ies 42 15 45 36 30 32 — Point d’Ostro de Cattaro ...... a2) 23° 30 .(36' |. 10°35 + S. Marco (isle, the fort) Ragusa.|42 37 45 |35 44 20 (Correspondence Astronomique, i, 456.) 396 Col. Beaufoy’s Astronomical, Magnetical, [May, Astronomical, Magnetical, and Meteor By Col. Beaufoy, F. ARTICLE XIV. Bushey Heath, near Stanmore. ological Observations. 1. Latitude 51° 37’ 44°27” North. Longitude West in time 1/ 20°93”. March 29, Lunar eclipse. 5 Astronomical Observation. Moon rose eclipsed. End of eclipse...... 8 0’ 9 Mean Time at Bushey. Magnetical Observations, 1820. — Variation West. Morning Observ. Month, Hour, March 1| 8h 40! 2} 8 30 3} 8 35 4| 8 35 5} 8 40 6) 8 35 7| 8 40 8]; S 40 9| 8 40 10} 8 40 11 8 35 12| 8 40 13} 8 35 14) 8 35 Rep ta AS 16/ S 40 Dire Suess 18; 8 40 19} 8 40 20} 8 35 21 8 35 22; S 40 23} 8 35 24) 8 35 25+ 8 40 26); 8 40 27; 8 35 28} 8 35 29) 8 40 8 $35 Stl (Sikes Mean for Month, its ai Variation. 24° 30’ 57" 24 32 O7 24 30 47 | 7 Hour. jh Sag (ee ee aia Spe a Sia rane ee ey 30’ 25 Noon Obsery. Variation. 24° 35’ 04” 24 37 39 24 37 25 24 39 49 24 38 55 24 41 #12 24 40 32 24 43 O09 24 39 33 aooaane| AAA Evening Observ. Hour, 6" 05! a 15 10 15 15 13 24 32 55 Variation. 240 33' 28” 24 33 42 24 32 16 24 34 12 24 32 53 24 32 57 24 33 34 24 36 34 24 35 13 24°°33' 233 24 33 4d March Ist, the needles were unsteady; during the night of the 2d, there was a violent storm of wind from N.W. accompanied with snow. 8 1820.] and Meteorologicaé Observations. 397 Meteorological Observations. Month. | Time. | Barom. | Ther.} Hyg. | Wind. |Velocity.;}Weather.| Six’s, March Inches, Feet. Morn....| 29°048 38° 71° INW by W Cloudy 333 1¢ |Noon....| 29°095 Al 59 NW Cloudy A2 1 Even....) — = = = == adh Morn,...| 28°460 | — 76 NW Stormy t 92\Noon...., — — —_ _ _ = Even....) — = _ _— ‘ ren “|Morn....| 29°285 | 29 | 72 | Nby W Cloudy 3¢ \Noon,...} 29°326 32 65 NNE Fine 34 Even,... = - =— = ps : 24h Morn....| 29°532 | 28 TL NNW Very fine 4< |Noon....| 29°510 34 64 NNE Cloudy 35 Even....; — _ = —_— _— 252 Morn....| 29°712 | 29 66 NE Clear z 4 Noon....| 29°727 33 58 ENE Fine 35 Even....) — == =. ize _ 25 Morn....| 29694 | 28 | 15 NNE Snow ‘ : 7 Noon....| 29°668 | 33 63 NE Sn.show.| 34% Even.. _ cael = _ _— 23 Morn....| 29°690 27 71 NNW Cloudy : P 74 |Noon....| 29°652 3l 72 W Snow 36 Even. _ = = = — 81 Morn... 29°71T 32 716 NE Very fine ‘ i f Noon....| 29°785 | 39 63 NW Very fine 395 Even... —_ = = = —_— ‘ 27 Morn....| 29°708 30 68 W byS Clear ci of Noon....| 29°659 | 44 63 SSW Fine 453 Even....) — = = = _— 29 f Moru....| 29:349 | 33 | 80 s Cloudy ‘ 1049 |Noon....) — = _~ — —_ 43 Uiecss.. — — — — 30 Morn....| 29:134 44 70 ESE |Clear i) Noon....| 29°129 48 56 SE by S Very fine 504 Even....| — — _ —_— — ‘ 308 f Morn....| 28°975 33 5 ESE Fine = 12. |Noon....| 28946 45 64 ESE Fine A5 U Even....) — — — _ — 342 Morn....| 29115 | 38 | 80-| WbyS Fine ‘ 4F 132 |Noon....| 29-232 AT 56 W Fine 48 Even....) — — — — _— eS Morn....} 29-611 | 40 | 89 SSW Fog t a af Noon....| 29662 | 52 | 74 | WSW Cloudy |” 52 Even....| — — —_— — — 4G2 Morn....| 29:800 | — _— WNW Foggy : a 15< |Noon... — _— — — — 605 Even....| — _ 82 = — Ab Morn... .} 29-929 AG 83 ESE Fog ¢ 164 |Noon....| 29-912 52 66 NE Cloudy 52% Eyen ...)| — — — — — evel Morn....| 29°805 | 42 83 NW Foggy ‘ 2 1T< |Noon....| 29:800 | 47 18 N Sm. rain| 48% cjEven...., — — — _— | — 392 Morn...-| 29°S90 | 36 13 NNE Very fine : Lew 29°874 45 54 NE Very fine} 47 185, |Noon.. ek |Even. 398 Month. | Time. | Barom. | Ther. March Inches. Morn... .| 29°787 38° 192 |Noon,...) 29°757 2 Even....) — — Morn,...| 29-783 35 202 |Noon,,..) 29°783 42 Even,...| 29°770 Al Morn... .} 29°688 35 a} Noon....| 29°600 44 Even ,....| 29°525 44 “|Morn... | 29-322 | 42 at Noon....} 29°330 50 Even... ‘ 29-290 46 Morn....) 28°848 42 zx} Noon, ...| 28°734 | 42 Even ,..| 28-600 43 j Mern,.,.| 28°605 40 24< |Noon....| 28°514 46 l Even ,...| 28°428 Al Morn,...| 28°744 35 25< |Noon.... 28-863 46 Even ....) — — Morn.....| 29264 } 34 20} Noon....| 29°200 | 40 Even..,.| 29-175 45 Morn,...} 29°307 47 x} Noon... .| 29°309 50 Even....} 29°309 48 Morn....| 29°513 45 2} Noon....| 29°541 55 Even....| 29°552 48 Morn....| 29°633 50 29< |Noon....| 29°651 56 Even ....} 29°600 51 Morn....| 29°488 AT 804 |Noon....} 29°508 59 Even ....} 29°508 52 Morn....| 29°550 45 $1<¢ |Noon....} 29°515 56 Even....| 29°185 50 Col. Beaufoy’s Meteorological Observations. Hyg. 49° 64 [May, Wind. }Velocity.| Weather.|Six’s. Feet. NE by N Cloudy 34 NE by N Showery| 43 NE Cloudy : 34 NE Cloudy 44 SE by E Cloudy W by N Cloudy $30 WNW Cloudy AT WNW Cloudy NW Very fine ‘ 384 WNW Fine 50 SW by W Cloudy 4 W Cloudy ; - W Hail 46 WwW Storm W Fine 7 ‘ 31g Ww Cloudy 49 NE Cloudy N Very fine ‘ 303 NNW Very fine} 47 WwW Snow = SSW Cloudy ; 27§ ae by S Rain 45 ‘SW Rain SW Rain ‘ 453 pics Showers | 5h Cloud >) W by S Fine t § 43 W byS Fine 554 SW Cloudy 45 wsw Cloudy |¢ 454 WSW Cloudy 58 SSW Clear Ad NW by N Fine ‘ NW by N Fine 594 NW Very fine aan WSWw Clear t t WSW Clear 57 W by N Clear Rain, by the pluviameter, between noon the Ist of March, and noon the Ist of April 0-246 inch. The quantity that fell on the roof of my observatory, during the same period, 0°263 inch. Evaporation, between noon the Ist of March, and noon the Ist of April, 4°17 inches. 1820.} | Mr. Howard’s Meteorological Table. 399° ARTICLE XV. METEOROLOGICAL TABLE. Baromerer.| THERMOMETER, Hygr. at 1820. Wind. | Max,| Min. | Max, Min. | Evap. |Rain.! 9 a.m 3d Mo. March 1N W/29°62/28-98| 45 31 16, 69 2IN W)|29-79129'02| 35 7 — 83 3.N W/30:08/29:79] 37 26 | seat "3 4\N E/30°31/30:08] 38 26 82 5IN _—-E)30°31/30°28| 38 22 — 66 6| N_ |30:28/30 26| 37 Q1 74 7| N_ |30°35/30-20|) 39 31 — If ty SIN E)30°35|30°28] 44 26 81 9} W_ |30:28)29-98| 49 30 78 10' S = |29:98|29:76| 47 26 78 11S = E/29°76/29°59| 55 28 97 128 E\29°68|29°59| 47 36 69 13IN W'30:16)29°68| 53 32 75 14/S W 30°33 30:16! 58 47 55 88 |@ 15IN W)30°44|30°33) 53 4S 84 16S —E/30°44)30°34) 55 29 98 17/S W/30°42!30°32| 52 32 99 ISIN ~—-E|30-42/30°33) 51 32 84 19\IN _ £/30°35/30°33| 46 32 — 70 20IN —_—E/30°35/30°25| 48 30 79 21IN W/{30°25/29-89} 51 39 57 74 1¢€ 22} N_ |29°89/29°38| 55 44 13|- 67 23IN W/29:38/29'10| 53 39 — 67 24| Var. |29-20/28'91| 52 33 _ 67 25| N_ |29-79]29-20| 49 26 64 26S W/29°83/29:79| 52 43 5| 62 27/8 W/)30'01/29°83| . 55 45 g} S6Gt 28} W_ 130°15|30'01| 61 47 56 86 29S W/)30'15/30-04| 62 53 78 \O 30\N Ww 30°07|30°04| 63 29 76 31) Var. |30°08|30-04) 63 38 34 79 30°44/28-91| 63 21 | 2:02 10:37) 997—62 The observations in each line of the table apply to a period of twenty-four hours, beginning at 9 A. M. on the day indicated in the first column, A dash denotes, that the result is included in the next following observation. 400 Mr. Howard’s Meteorological Journal. [May, 1820. 4 REMARKS. Third Month.—1. Cloudy: a strong gale of wind during the night. 2. High wind continues: some snow about seven, a.m.: very stormy night: much damage was done on this and the preceding night to buildings and garden waiis in this neighbourhood. 3. The wind still very high from NW, though a fine clear morn- ing. 4. Fine morning: Cirrus, 5. Fine, 6. Some snow in the morning. 4. Snow in the night. 8—10. Fine. 11, 12. Hoar-frost. 13. Cloudy: fine. 14—17. Overcast. 17. Thick fog. _18—20. Cloudy. 21. Lunar halo and corona at night, followed by wind and rain. 22, Cloudy and fine. 23. Windy. 24, 25, Cloudy. 26. Hoar-frost: showery. 27. Cloudy: light showers. 29, Fine: the lunar eclipse very well seen: a Stratus at night afterwards. 30. Fine: Cirrocumulus: Cirrus, 31. Hoar-frost: fine. RESULTS. Winds: NE, 6; N,4; NW,8; W,2; SW,5; S,1;SE,3; Var.2. Barometer: Mean height For the month, ,..... $10.6) ero lite s-sreiele sisige aisblaute hein « 29°971 inches. For the lunar period, ending the Gth, ............- 30°022 For 14 days, ending the Ist (moon north) ........ 29-911 For 13 days, ending the 14th (moon south) .. .... ~ 30°012 For 14 days, ending the 28th (moon north),,...... 29961 Thermometer: Mean height Tor the month........ cesses Ee OL diode Bieetetats « 41°387° For the lunar period, ending as above ........ ... 35°362 For 30 days, the sun in Pisces. ......-..-- Bien coe oda ao: Hygrometer: Mean for the month . .........--- Buys 5 Ba ae 78 PCAN ON ALON Gs een acs aco msleniale Heed Ye | 2. In two grains sulphite of barytes .. 0°29 3, In 15:13 grs. of sulphuret of silver, 1°92 Now 19:67 grs. approaches to half the weight of 42°9 grs. which was the whole chloride of sulphur subjected to analysis. 412 Dr. Thomson on [JuNne, The ammoniacal solution of chloride of silver, being saturated with muriatic acid, let fall the chloride of silver which it con- tained. This chloride, being well washed and dried, was found to weigh 83:7 grs.; but as chloride of silver is a compound of 4-5 chlorine + 13°75 silver, it is obvious that 83°7 ors. of it contain 20°63 grs. of chlorine. This of course is the quantity of chlorine contained m the 42:9 grs. of the chloride of sulphur subjected to analysis. From the preceding details, it is obvious that the chloride of sulphur was composed of @hlorne eee ee 06S ee. 46°0e Perfil epee ie aad se fe LOGI es S0°G0 40:30 OSSNE Hehe ela leas eek te DOO sseee ye) HDS 42:90 100-00 The loss of six per cent. incurred during this analysis will not . perhaps be thought excessive, if the length of time which the analysis took up, and the volatile nature of the chloride of sul- phur, be considered. It is. probable that the greatest part of this loss was owing to the escape of a portion of the muniatic acid into which the chlorine was converted by agitating the chloride of sulphur with water. Let us now see what inferences respect- ing the constitution of chloride of sulphur we are entitled to draw from the preceding analysis. An atom of sulphur weighs 2, and an atom of chlorine, 4°5. Hence it is obvious that our chloride of sulphur was not a compound of one atom sulphur + one atom chlorine ; otherwise the chlorine, instead of merely exceeding the sulphur a little in quantity, would have been more than double its weight. If we suppose the chloride examined to have been a compound of two atoms sulphur + one atom chlo- rine, then the weights of the sulphur and chlorine would be to each other as 4 to 4:5; but 4: 4°5 :: 45°85 : 51:58. Therefore, if the quantity of chlorine obtained in the preceding analysis had been 51°58 instead of 48°09, the chloride would have been com- posed exactly of two atoms sulphur + one atom chlorine. Now I have little doubt that from the greater volatility of the chlorine when compared to the sulphur, the greater part of the loss would be owing to the escape of it, or of the muriatic acid gas, into which it was converted. I conceive myself, therefore, entitled to conclude that the chloride of sulphur which I subjected to analysis was a compound of two atoms sulphur + one atom chlorine. It was, therefore, a subbichloride of sulphur. It is scarcely necessary to say that I repeated the preceding analysis a second time without coming any nearer the truth. I conceive it, therefore, quite unnecessary to state the details of the other analysis. Jt was conducted precisely in the same way A820.) the Composition of Chloride of Sulphur. 413 as the preceding, and the phenomena which it exhibited were precisely the same. Now that we are acquainted with the composition of the sub- bichloride of sulphur, which I sw>jected to analysis, the pheno- mena which presented themselves during the analysis, and which I have partly noticed above, admit of an easy and obvious explanation. When the subbichloride is agitated strongly in water, it gradually deposits one half of its sulphur. The remain- ing half of the sulphur is to the chlorine in the proportion of one atom to one atom. Water is decomposed by the mutual action of the chlorine and the sulphur which continues united to it. The oxygen of the water unites to the sulphur, and converts it into hyposulphurous acid, while the hydrogen of the water unites to the chlorine and converts it into muriatic acid. Thus one half of the sulphur is deposited while the other half is converted into hyposulphurous acid. The hyposulphurous acid and the muriatic acid dissolve in the water. This decom- position does not take place at once, because, from the great specific gravity of the subbichloride of sulphur, and from the viscidity of the sulphur first evolved, great agitation and a consi- derable interval of time are necessary before the two liquids can come sufficiently in contact to act upon each other so as to pro- duce mutual decomposition. New portions of hyposulphurous acid, therefore, and of muriatic acid, are formed at each succes- sive agitation, and dissolved in the water. But hyposulphurous acid, in order to be a permanent sub- stance, requives to be united to a base. When merely dissolved in water, it speedily undei_oes decomposition, letting fall sul- phur, and probably being converted into sulphurous acid. Hence the reason why the liquid always continued opalescent: it was owing to the continual decomposition of tne hyposulphu- rous acid, and the continual evolution of new portions of sulphur in proportion as the old portions subsided: but when the hypo- sulphurous acid was saturated with ammonia, its spontaneous decomposition was stopped. This was the reason why the liquid became transparent, and why I was able to separate all the sulphur from it when it was saturated with ammonia. Hyposulphurous acid is not precipitated by the salts of barytes. Hence it was only the sulphurous acid which the liquid contained, and which had been formed at the expense of the hyposulphu- rous acid, that was precipitated by means of the nitrate of barytes. Nitrate of silver does not precipitate hyposulphurous acid, the hyposulphite of silver being a soluble salt. Hence the reason why nitrate of silver only threw down the muriatic acid leaving . the hyposulphite of ammonia still in the liquid, or rather convert- ing it to hyposulphite of silver. But Mr. Herschell has shown that hyposulphite of silver is not a permanent salt, being gra- dually decomposed into water and sulphuret of silver. Hence 8 ‘ 414 Dr. Thomson on J UNE, the reason of the gradual deposition of sulphuret of silver, and hence the reason of the length of time necessary to throw down the acids in the liquid by means of nitrate’ of silver. The muriatic acid was immediately thrown down in the state of chloride of silver; but the hyposulphurous acid was converted at first into hyposulphite of silver, which slowly deposited sulphuret of silver. Thus the muriatic acid was thrown down in the state of chloride of silver, while the sulphur of the hyposulphurous acid was precipitated in the state of sulphuret of silver. Thus the action of water upon the subbichloride of sulphur cannot be completely understood till we know the properties of hyposulphurous acid and of some of its salts; but when these are once known, nothing is simpler or more beautiful than the series of decompositions which take place during the analytical experiments which I: have described in this paper. It 1s not surprising then that I did net succeed in my attempts to analyze the chloride of suiphur in the year 1803. I at that time had no notion of the existence of hyposulphurous acid, and was not aware of any other acid compounds of sulphur, except sulphuric and sulphurous acids. It will be seen by consulting my paper published in 1803, that there was no sulphurous nor sulphuric acid in the chloride, but that one or other of them made their appearance when the chloride was agitated with water. It will be seen too that when the liquid was precipitated by nitrate of silver, the precipitate had a brown colour, and of course must have been contaminated with sulphuret of silver. I was not able at the time to form any notion of the source of this sulphuret, and did not even attempt to determine its quantity. Indeed I thought the quantity of it was so small as to be msignificant, as far as the analytical results were concerned; but the preceding details are suiicient to show us that this notion was very ill founded. Had I subjected 100 ers. of the subbichloride of sul- phur to analysis, as 1 did in 1803, it is obvious that the weight of the sulphuret of silver formed during the analysis would have amounted to 35:27 grs.; while the chloride of silver would have amounted to 195:1 grs. Now if the 35-27 ers. of -suiphuret had been reckoned chloride (as I did in the analytical experiments published in 1803), they would have indicated 8-7 grs. of chlo- zine ; whereas in reality they indicate 4°47 gers. of sulphur. Thus the quantity of chlorine would have been overrated to the amount of 8°7 grs.; while the quantity of sulphur would have been made 41 ers. below the truth. It was equally out of the power of Berthollet and Bucholz at the periods when they made their respective analyses to take a correct view of the phenomena. They were just as ignorant of the nature and properties of hyposulphurous acid as I myself had been. Of course their experiments do not lead us to any correct views respecting the constituents of the chloride of sul- phur which they subjected to analysis ; neither are they suscep- 1820.] the Composition of Chloride of Sulphur. ' 415 tible of being corrected by the application of more recently discovered facts. Hence as far as the analysis of the chloride goes, their researches are quite useless. Had I taken the trouble to separate the chloride of silver from the sulphuret, and had I recorded the weight of each in my original paper, my expe- riments of 1803 might have been applied with ease to determme the true composition of the chloride of sulphur which [ at that time subjected to analysis ; but the neglect of these essential facts prevents the possibility of making any use of my experi- ments, and of course renders it quite unnecessary to correct them. I am of opinion that whenever sulphur and chlorine are united together by my original process ; namely, by passing a current of chlorine through flowers of sulphur till the whole is liquified, we always form a subbichloride of sulphur, or a com- pound of one atom chlorine with two atoms of sulphur. At least I have repeated the process three times, and each time the liquid formed was a subbichloride. I have not tried the effect of continuing the current of chlorine gas as long as it continues to be absorbed ; but it would probably form a chloride of sulphur, or a compound of one atom chlorine and one atom sulphur. But in the chloride of sulphur which I prepared and attempted to analyze in 1803, the current of chlorine was continued a consi- derable time after the sulphur was liquified. Hence there was probably more chlorine in it than in the liquid, the analysis of which has been related in this paper. This was probably the reason why its specific gravity was different from that of the liquid obtained by Berthollet, and Bucholz, and from that which I employed for the present analysis. Berthollet, or at least Bucholz, had prepared subbichlorides of sulphur; while the liquid on which my original experiments were made was proba- bly a simple chloride. ; That a compound of one atom of chlorine and one atom of sulphur exists as well as a subbichloride of sulphur, appears to me sufficiently demonstrated from a synthetical experiment related by Sir H. Davy. He found that when dry sulphur is put into chlorine gas, the gas is absorbed by the sulphur, and a liquid chloride formed. Now he observed that 10 grs. of sul- phur were just capable of absorbing 30 cubic inches of chlorine gas; but 30 cubic inches of chlorine gas weigh 22-875 gers. According to this experiment, 10 grs. of sulphur combine with 22°875 grs. of chlorine; of consequence, two grains of sulphur would combine with 4°575 grs. of chlorine. Now 2 is the weight of an atom of sulphur, and 4-575 only exceeds the weight of an atom of chlorine by 0:075 gr. An error of half a cubic inch in the quantity of chlorine absorbed by the sulphur would have produced this difference. I think, therefore, we may con- clude, without any hesitation, that Davy’s synthetical chloride was a compound of one atom chlorine + one atom sulphur. 416 M. Peschier’s Phystco-chemical Inquiry into [JunE, Unfortunately Davy has not mentioned any of the properties of the chloride which he formed, though there is every reason to believe that its characters must differ in several particulars from those of the subbichloride of sulphur. From the facts stated in this paper, we may conclude that chlorine and sulphur are capable of uniting at least in two pro- rtions. These compounds are : ; 1. Chloride of sulphur composed of one atom chlorine + one atom sulphur, or of PAGE is seu suid c OO we 8 69°23.02... 0200 2OO@ STU CL ela eee 2/5 ene SOT es ext ee 44-44 100-00 2. Subbichloride of sulphur composed of one atom chlorine + 2 atoms sulphur, or of Gorge... OORT, cacao cede 100-00 eens ovate, oa te ces rae eae 88:88 100-00 It is not unlikely from the analogy of oxygen that sulphur may be capable of uniting likewise with two atoms and with three atoms of chlorine ; but as these compounds are not likely to be of much utility, it might be considered as a waste of time to endeavour experimentally to obtain them. Articie III. Physico-chemical Inquiry into the Red Snow of the Environs of Mount St. Bernard.* By M. Peschier. THE singular phenomenon of the red snow has excited much attention, on account of that which the navigators in the first arctic expedition had observed, and even collected, in these high latitudes. Observations of the same kind have been called to mind which were formerly made by our De Saussure in his attempt to analyze the colouring matter which sometimes tinges the snow on the high mountains. A chemical and physical’ examination has lately been made in London of this substance brought from the arctic regions, and signs of organization even thought to be perceived in it. We have ourselves more than once observed this phenomenon on the snow on the Alps ; and a lover of mountains, who is nearly connected with us, and who, like us, has the advantage of living in correspondence with the * From the Bibliotheque Universelle, for Dec. I8i9. 1820.] theRed Snow of the Environs of Mount St. Bernard. 417 respectable prior of the Convent of Grand St. Bernard, has availed himself of this circumstance, and of the acquaintance of the learned monk with natural history, to address to him a series of questions on the subject. He has very obligingly answered. them, and these answers seem to us to throw much light on the phenomenon as connected with the localities. On the other hand, this same correspondent having been sa kind as to send us, at two different times, samples of the colouring matter collected by himself with great care, we have requested M. Peschier, Member of the Physical and Natural History Society, and of the committee of chemistry of the Society for the Promotion of the Arts, to undertake the ana— lysis of these samples: This he has been so kind as to doz and we think that our readers will be obliged to us for com- municating to them these two papers, which those who feek interested in the question of the red snow will not find out of their place in our journal. Questions and Answers respecting the Red Snow of the Environs of Mount St. Bernard, Is the red snow permanent ? It is permanent. Is it always seenin the same place ? It is always seen in the same place. It generally occupies the plateaux, commanded by declivities covered with snow. Is it concealed by the snow which falls upon it, or does the latter become red by the contact ? It is concealed by the snow which falls on it, and the latter does not become red by the contact. I have seen the red snow on the Buet, the St. Bernard, the Col de la Seigne, the Bonhomme: is it ‘generally found at the same elevation as these summits in the other parts of the glaciers? It is‘found at this level, and also higher and lower, provided there are masses of snow sufficiently large not to melt during the summer. It is sometimes found onthe glaciers. Is it more abundant at certain times ? After high south, or south-west winds. Has it been noticed whether it was red at certain depths ? To the depth of two or three inches. Would it not be possible to obtain by filtering it, a residue which might be analyzed ? Without having made the experiment, I believe that it would furmish an earthy and ferrugimous residue which might he analyzed. Is there any opinion on the cause of this colour? I do not know that there are any opinions on this cause : it might be ascribed to the colour of the earth, especially the ferru— Vor. AVEN VI. 2D 418 = M. Peschier’s Physico-chemical Inquiry into [Junz, vinous earth, which the winds carry away, and let fall on the snow, as elsewhere. Does not the red snow give rise to certain superstitions ? Absolutely to none in our country; the people do not even nie to it. as it been observed whether it is more or less abundant according to the temperature of the air? It has not been observed, but the more the season advances, the more abundant it is; because as the winds bring fresh sup-- plies of earthy matter, they are the more easily perceived. Tn particular, would it not be more or less abundant in propor- tion as the melting of the snow has been more considerable ? The melting of the snow and the rain occasion little streams, which flow over the snow and make fwrows in it. In these furrows, hollows are formed, as there are ina rivulet ; it is there that itis more particularly red, because the water, carrying with at the colouring matters, allows them to precipitate, on account aof the diminution of the force of the current. In what places is the red snow seen the most frequently, and in 4he greatest abundance ? It is where the snow resists dissolution the longest ; at the bottom of declivities covered with snow, because the red sub- stances are carried and deposited there by the currents. Do the chronicles, manuscripts, or ancient works, make any amention of this snow? T have never found any thing on this subject. Does it exist on the Appennines as well as the Alps ? I have never thought of inquiring. is it observed rather on one side of the Alps than on the wther? It is found on one side as well as on the other. Has any body ever seen it fall red? Never ; not even old people. T have seen the same effects on snow occasioned by substances wf anothercolour; these consisted oflittle particles conveyed by the ewinds, which had been taken up from the ground, or rocks, in the neighbourhood, which were of clay or plumbago; then the snow was black, and presented the same phenomena as the xed. I remember to have seen somewhere that an author aseribed the colour of the red snow to the beams of the sun combined with at. But why then should not snow be every where red, since the sun-beams fall on one mountain as well as on another? Itis to be observed that sometimes the edges of the snow which are most an contact with the ground are also coloured in the same manner. ‘There are pretty generally in our mountains soils ferruginous by pyrites. There are even spongy slates (ardoises spongieuses) which contain pyrites, which have left vacancies by their solution, and which, being carried away by the water that flows 1820.] the Red Snow of the Environs of Mount St. Bernard. 419 over the snow, may very well colour it. A league from our hos- pital, at the summit of the Col Ferret, there is a mine of specular magnetic iron ore (fer spéculaire aimanté); it may be recognized in spring by the snow which is strongly tinged with red. Lam, Xc. BisExx. St. Bernard, March 6, 1819. P.S. As soon as red snow can be had, I will filter some, and send you the residue; but I shall not find any before the middte of June. — Analysis of two Samples of Red Snow of St. Bernard. By M. Peschier, Member of the Physical and Natural History Society at Geneva. Extracted from a Memoir on the Subject, read to the Society. I am not acquainted with any chemical inquiry into the cause of the colour of the red snow of the Alps, except that made by our illustrious countryman in 1778, and which is related in the third volume of his Travels. The results of this inquiry are confined to showing, that the residue of the red snow had an earthy appearance, that when laid on burning coals, it emitted a smoke, smelling like burnt grass ; that it furnished a dark-brown solution, with muriatic acid, by the aid of heat, and a tincture of a beautiful gold-yellow with alcohol, which left, as the residue of its distillation, an oily substance, of a yellow-brown, having, while burning, the smell of wax, and that the loss in weight of the residue in this operation was =,ths, which had made him at first consider it as a dust of stamina, and that microscopical observations had left him in doubt. As I was not acquamted with any thing else on the subject, I have always wished to see the attention of chemists directed to this interesting pheno- menon. Two favourable opportunities having offered, I have thought it my duty to take advantage of them; and the following are the essential parts of my inquiry : My first operations were upon two residues of red snow, col- lected with great care by the Prior of Great St. Bernard. One of these residues, marked No. I. had an earthy appearance, aud a ferruginous, dirty-yellow colour. No. II. had the character of a coarse vegetable earth, in which the naked eye could distinguish fragments of lichen and of moss. It came from a small spot of red snow, above which there was a reddish tinge, supposed by the Prior to be produced by a cryptogamous plant, which assumes this colour as it putrefies. This cause, he says, m the note which accompanies these residues, rarely occurs, and does not offer large coloured surfaces. No. I. when strongly heated, Jost 0-10 of its weight, and assumed a darker colour. No. UH. emitted a pretty considerable smoke smelling like burnt grass ; lost 0-40, and left a brilliant residue, of a violet colour. 2Dp2 421) M. Peschier’s Physico-chemical Inguiry into (June, Subjected to the action of boiling alcohol, No. I]. experienced only a very slight effect: cold and warm water did not produce any more. Fifty grains of No. I. when submitted to destructive distilla- tion, yielded an aqueous ammoniacal hquor, some drops of empyreumatic oil; and left a coaly residue, weighing 32 grs. No. I. not containing any combustible substances, was not subjected to the same trial. One hundred grains of No. I. experienced but slightly the action of muriatic acid, even with the aid of heat. The insoluble part, treated with nitric acid and an addition of sugar, furnished by means of a long ebullition, a solution which had a strong orange tinge ; and left a residue, weighing 65°50 grains, composed of fragments of stones and of rock crystal. The acid solutions furnished alumina 6°35, peroxide of iron 21°35; and there remained in solution in the pure alkaline liquor employed in the separation of the alumina, a vegetable principle, which had been dissolved by the acid, and which communicated to it a strong yellow colour. Its products are : Siliceous substance...-... . 65:50 AVOID) | 4 675.6 0-2.2. 3,886 eiprasduate te CO reIO Peroxide of iron .......... 21°35 Soluble organic substance .. 6°80 One hundred grains of No. II. furnished, with muriatic acid, a violet-brown solution, such as M. de Saussure obtained ; but the action of this acid being found too weak to dissolve the oxide of iron, it was necessary to follow the same process as in the preceding operation, and the principles recognized were : Insoluble substance........ 20°00 Alama. F200 6s sg Ov awe 4°25 Peroxide ofiron. .......... 31°25 Chalke cid. wees $d sews 6 0-60 Insoluble organic substance. . 37°59 Ditto soluble as in No. I.... 6°50 A short time after this, having received from the Prior, by the medium of Professor Pictet, two bottles of water of red snow, with all the substances met with on its surface, the following experiments were made, which seem to throw a much greater light.on the cause of this colour. One of these bottles, No. I. contained 27 ounces of water; it came, as the Prior expressed himself, from a snow which gene- rally covers in June large tracts; and which had a bright rose 1820.] the Red Snow of the Environsof Mount St. Bernard. 421 colour, like lake; it had been covered with fresh snow at the time when it was collected, and did not show upon its surface any substance foreign to the colouring matter. ‘This snow had changed its colour in melting ; the plebae visibly became of a fainter colour before they melted, merely by the transition to a higher degree of temperature. It covers large spaces in June. This water was colourless, slightly turbid, tasteless, had a smell analogous to that of a small quantity of decayed "vegeto- animal substances ; it furnished in this state a gre eenish liquid with hydrosulphuret of ammonia, and assumed, after the lapse of some hours, a violet tint with the infusion of galls: it did not aifectthe test papers; when filtrated, it experienced fromthe above tests the same effects: it was rendered slightly turbid by oxalate of ammonia, and gave no precipitate with salts of Anyhes 3 wken exposed to the action of ebullition in an apparatus adzpted to receive the carbonic acid gas, it gave buta very slizht indication of it: when evaporated to dryness, it yielded a small deliquescent residuum, having the properties of extractive matter, and emitting on the coals a vegeto-animal smell. The remainder left on the filter by this water, weighed 68 grs.; in this state it was externally of a greyish- violet, aad internally it was of a very lively violet-red colour, which the action of the air soon changed to that of the surface. It had penetrated into the substance of the paper, and was not to be separated from it without difficulty. To the touch it was unctuous ; it was pee rulent, and strewed with some thin filaments of vegetable substances. When exposed to the action of alcohol with the aid of heat, it gave a tincture, of a deep purplish-yellow, aad required several successive boilings with fresh alcohol before it ceased to cclour it: the loss which it experienced by the solution of the colouring principle was found to be the same as that mentioned by M. de Saussure. The spirituous liquids united yielded by distillation a colourless alcohol, having no ‘extraneous taste, the last portions of which, being evaporated to dryness, left on the sides of the capsule a layer of a saftron-yellow, traversed by greenish dendritic ‘ramifi- cations. This yellow substance had an acrid taste; wlea thrown on burning coals, it emitted a smoke that had ‘a. smell like burnt sugar, “which was presumed to come from the alcohcl: it was insoluble i in water; but soluble in alcohol, ether, oil, the pure alkaline solutions, and chlorine; this last liquid d estroyed its colour in dissolving it. These properties, belo onging to resinous substances, very well explain ifs nature, Ten parts of the residue left by the water, strongly heated, emitted a copious s smoke, with the me Hofanimal substances in combustion, and left a residue of a pale.red, with a loss of 2a Ore 2 422 M. Peschier’s Physico-chemical Inquiry into [J UNE, Twenty-five parts of this residue, treated by nitro-muriatic acid were found to be composed of Siliceous substance .... 14:18) Peroxide of iron. .. 3°25 : ne Ce ae Ped mcrease Ob Vile woe SPE) Piet hes er weight can only be Resinous principle. .... 3°20 raked 2 ie rays Organic ditto. ....... . 2:25 | Fe geek aks Ditto, ditto, soluble.... 1°75 J 26°48 The water in the bottle No. II. was from a red snow, which is met with on the edge of the great masses of white snow; its colour was not so bright as that of No. I. and it did not change in melting. This water, of which there was but a small quantity, was con- tained in a narrow bottle, the sixth part of which was filled with a brown and heavy deposit: when filtered, it retained a bright yellow colour, and left a residue, weighing, when dry, 48 grs. This water stained the test papers red, by the effect of the carbonic acid; it gave, with the above-mentioned tests, liquids more coloured than that of No. I. and the oxalate of ammonia acted more powerfully upon it. The residue had a brown tint ; it was rough to the touch, and sprinkled with small fragments of rock crystal: alcohol and water had no sensible effect onit; the first furnished by its eva- poration a small quantity of a yellow tincture ; exposed to a brisk heat, it emitted neither smoke nor smell ; treated by nitro- muzriatic acid, 25 parts were composed of Pda sd, « nsdn Wrenches lore che toi stamens Peroxide of iron *. ..«.'s...« 12°34 Chalke scetiientiaes et eked an O20 Organic substance and water. 10°00 23°79 The results of these different analyses seem to indicate that the red colour of the snow found in summer on some elevated parts of the Alps, arises from two different causes ; viz. first, from a greater or less quantity of oxide of iron spread over its surface in a very great state of division, and in a very high degree of oxidation ; secondly, from a resinous vegetable principle, of an orange- ved colour, belonging, according to all appearance, to some eryptogamous plant of the genus alga, or lichen. And as nature presents us with a very great number of vegetables in which iron exists in pretty large quantity, it does not seem to be an inadmissible supposition, that this iron formed, perhaps, one of the immediate principles of the vegetables in question, of which —_— << 4820.] the Red Snow of the Environsof Mount St. Bernard. 42% only the fragments are found, and that, in conjunction with the resinous principle, it is the direct cause of the colour. The pro- portions in which this metal is found, in these four analyses in 100 parts of the residue, are: PLCSICUG, INGre..'s\ee hanced, ct OO SE INO Lala aids ee's!is « 31-25 Water NOs. aso sco atinsca dle OU i NR et a 6, Articue IV. Meteorological Journal kept at Manchester for 1819. By Mr. T. Hanson. (Witha Plate. See CV.) (To Dr. Thomson.) SIR, Manchester, March 8, 1820... Enctosep I have sent you my annual results of the weather for the past year; also the results for the month of January, accompanied with a chart of the daily notations. To the meteorologist, the chart scarcely needs any elucidation- ‘The first and second horizontal spaces from the top ate allotted for the days of the month and moon’s age ; the five following are for fog, rain, snow, hail, and thunder, as marked in the margin. The spaces are darkened in proportion to the duration of the me es occurrences, paying attention to the time of the day or night. The course and strength of the wind by curves, with respect to the wind’s force, 0, is considered a calm: 1, a gentle wmd; 2, a little stronger ; 3, a strong wind; and 4, a boisterous wind, or a hurricane. With respect to the barometrical curve, I have depicted the real oscillations of the atmosphere as accurate as circumstances would allow. The curve of temperature is formed from the daily extremes registered by a Six’s thermometer. As the coldest part of the day is generally about an hour or two before sun-rise, and the warmest about two o’clock in the afternoon, those points in the chart denoting those periods of the day are carefully noted. Some- times the extremes of temperature otherwise happen, particularly on the breaking up of a frost, or the setting in of one; when that is the case, the time is accordingly noted. The left side of each daily perpendicular space denotes the morning, and the right the evening. 1 am, Sir, your most obedient servant, Tuomas Hanson. = & Ey | | | | $ 6 1S j91/s¢ 12) FOlPh|BS 16, 13) F Giz! 610GE L-O¢ wie bate | 89-66 | ‘oY fsuvosy : o | { | junuuy 1 | | ' : a eet |S lene ies! | eel Exon a 3 ies | ae) ae a = an | a aa a Sl Se agen I & 0/0 (9 0 lo jo jo jo Ja '§ It Jo \9 |e ‘or's CB 0 [LI | GES | SI |9E|0% 99 | GE [31 |03-E |F9-0, 18-0 Li-6@ | Fo.0g | 19.68 | P75" IAC z 0/9 18 OFT [LITO |0 }9 |9 J% |9 [9 |G |L 9 |L € |0 J06 | 910-6 | OT |LE]ps| OF | 9-OF |1T |O9-F |GL-0| 40-1 00-63 | 70-08 | LE-Ga |** tt AON re 1/5 0 LIU [616 |0 [0 0 |b 9 |€ 16 |B LF J |@ (3 J81 | LIG-F | 16 \OF|OS OL | 1-0G JOL |OL-€ |1F-0| ¢6-0. 02-66 | ST-08 | Lo-63 [oo PO 2 Ols |p Sis [g19 [0 [0 0 1 IF 3 |L jo Lit & 0 jl |OLS-T | 6G jfElag, EL | ILE |L |O8-S |FG-0] F2-1 O1-GS | FEO | 18-G4% °° "dog S08 |f Dis [8 jt 0 |f 9 LS |F 9 |§ OLE O 1D |EL | 6C6-1 | 06 l6BJ0S) GL | 8:99 jy [03-6 198-0, 97-1 86-83 | Fz-08 em eet arth a = & |SB1 -3 0 |9 |O Jo jo 0 io 9ij3 |F& [TL OT jt [LI | O8e-] | 8% OS/o¢) 08 | SBFO |OL [09-2 | Fs-0; O6-0 4863 | F1-08 ees Ane 5 & {IT 8 {0 [8 (0 [0 |0 0 10 | | 63 |¢ 0 0 G 0 |&% | O1G-E | FS Balgr| EL | 6.69 |g |0G-3 08.0) F106 OF-63 | FI-08 peat SEL 0 Sto [6 [0 /0 JO 0 | Jo |e \6t jt ¢ |L B 0 \LI | FS6-0 | 8B \Sél96) HL | BOF |L | OS-I 98-0| 96-0 |#F-63 | 00-08 ZS Oli 0 Glo je iT 0 |5_ 0 Jo (a |L ot |\f |g 3 I \d \ft | O9T-3 | OG SajsE 99 | ¢-0¢ IT |02-E |0¢-0 86-0 | 80-63 | 90-08 = 0|t jo storlatio jo |s |o lo s |F let le 10 }€ \F |0 9B | OLG-E | LI jO&|se} 29 | G-Gh j1T |OF-S |29-0| BO-1 |S1-6a | 1-08 = O jf jt 8 (0 |StjO jO |E Jo It |e JO [St je f \9 0 jE |16 | epe.F | SE \seisa) Se | F-1h [Cf [ObE |6L-0) GLO \S6-9% | 26-6 KS 0 \§ 0 9 |I |130 |§ 13 jo |g |P |S ISF jo ¢ |¢é 0 0 26 | 690-F SS |62\be| 69 | S-1b 8 |Ga-g |98-0, GS-1 |9L-83 | £8.08 Qaoag¢oaeslacdeze ect he ee} ae | Sal see tet Sea SESE SREBBEERED Pleglie) F 2) P23) F) 2! F & 2|2 8 e|2/2/2/4/F 2/21 * a |eelsis])s| 2 |21 8 los| @ | 2 | # re Beg /e|Flz|"|: z ea Pee |e | 61 el ee Pye oe = s,2|5) |: = B S<| (3/8 ial ee a ? 2 =| r os : = ° =) . § gig at | E = F = 2 Z =| e £ =e | ws 2 ° a S @ "= 3g a” =| | = | a ee 5| nw ae = = — — ~ 5 *saqno19 “SUNTM “NIVU | ‘AUALVUTIWAL “AYVOASSAUd TVOIULYNOUVE "GIST 5 : ‘uopuo7ty jo PIAL OL oF apnysuo7y F ip}tO Ny LS off epPAyHUeyT a . ¢ : a woasing Bose eutOUL Aq "GI Vaz ay) ur ‘la jsayoungy 2D APHUL siorpHALasgY) POUL molf paonpap ‘spno y 5 aydsout, PIS OM soa ae x tt af Paenpap ‘spnojy pun PUTM MID aun posaduca 7 PUP IANSSILT jpaniaydsoudy ay) fo SYNSAT JNIILOJNLG9 }A 7 3 1820.] Mr. LHanson’s Meteorological Journal for Manchesier. 425 _ The annval mean pressure of the atmosphere is 29-68 inches ; highest, 30°34, which was on Jan. |, and on Sept. 21; lowest, 8°76, which occurred on Jan. 15; difierence of these extremes, 1-58 inch, which is considerably below the usual range. The mean daily curve of the atmospherical oscillations, as shown by the karometrical surface, measures a little more than 37 inches. Total number of changes, 116. The annual mean temperature is nearly 51°; the mean of the first three months, 42°9°; second, 55:4°; third, 62°4°; fourth, 42-1°: of the six winter months, 42°5°; six summer months, 58°9°. The maximum of 80° occurred on July 30; and the minimum of 20° on Dec. 10. Difference of the extremes, 60°. The fall of rain, hail, snow, and sleet, which have fallen in and about Manchester is a trifle more than 35 inches. The greatest quantities of rain fell in January, February, October, and Decem- ber; and the least in May. The notations in the above rain column for November and December have been furnished me by my friend Mr. John Dalton. My observations in those months were incorrect, in consequence of the frost breaking the bottle in the early part of November. A similar accident hap- pened in December. Mr. Dalton makes the annual fall of rain, &c. 35°240 inches. Total number of wet days on which rain fell more or less, 215; out of this number, 48 may be designated completely wet. The south-west, south-cast, and north-west, have been the prevailing winds. Strong or boisterous winds have rarely occur- red ; out of nine instances on which brisk winds were noted, eight blew in the first four months of the year. The only bois- terous winds of the year occurred in January, viz. on the 17th, 18th, and 25th, from the west and south-west. Snow has fallen on 25 days, and hail on 14 days. The reporter has only noted tive instances of thunder, viz. one in May, two in June, one in July, and one in October. The temperature of the past year has been generally above an average, although not marked with any great elevations or depressions. The following will show the comparative difference between the monthly means of the past year, and the general monthly means of the 12 preceding years. Jun. eb, Mar. Apr. May Twelve years’ general monthly mean 36-0 40-0 41°5 46-4 53-5 Monthly means in 1819. .......... 41°8 41-1 45°5 50°5 56-2 PRONE Sahin ii ale oe SUS. wae p-0°2 p. 1-4 p.4-0 p.4-] p.2-7 Sune, July. Aug. Sept. Oct. Nov. Dee. 585 61-4 60:0 56:0 50:0 42:6 37-6 59:5 64:2 65°83 57:1 501 406 35-5 — ae ——— p-1-0 p.2°8 p.5°8 p-Llop. dO m.2°3271 426 Mr. Hanson’s Meteorological Journal for Manchester. [JunE, General annual mean temperature upon the 12 years, 48-7- Annual mean of the past year, 50°7; difference 2° above the general mean. From the above it appears, that the temperature of 1819 has been uniformly above the general temperature, except in November and December. The greatest differences were m January, March, April, and August. My friend Mr. Edward Stelfox, of Lymn, near Warrington, has favoured me with his account of rain. Mr. 8.’s rain-gauge is exactly the same as- mine, and I can rely upon his account as correct: his farm adjoins the rivers Mersey and Bollin, and is very much subject to’ be flooded. In January there fell 3-224 inches ; February, 3013; March, 1:352; April, 1-988; May, 2°035 ; June, 2°641 ; July, 2649; August, 1-497 ; September, 1:695; October, 3-030; November, 1°881; December, 4:°300 inches: total, 29°305 inches. Mr. Stelfox says, that the snow which fell on the night of Dec. 29 and the following day measured eight inches in depth. He observed the temperature on the mornings of Dec. 10 and 13 to be 19°. Results of the Weather. (See the accompanying chart.) Barometrical Pressure-—Mean, 29°72 ; highest, 30°64; lowest, 28°60 ; range, 2°04; greatest variation in 24 hours, 1; mean daily spaces in inches, 5°5 ; number of changes, 8; real spaces in inches, 8°8; real number of changes, 20. Temperature.—Mean, 32:6; highest, 53; lowest, 13; range, 40; greatest variation in 24 hours, 19. Rain, &c.—1-075 inch ; number of wet days, 7; foggy, 21; snowy, 14; haily, 0. Winds.—North, 0; north-east, 2; east, 7; south-east, 6; south, 4; south-west, 5; west, 0; north-west, 2; variable, 55 calm, 0; brisk, 1; boisterous, 1. The greatest daily variation of the barometer took place on the 19th, accompanied with fog, rain, and snow, and was pre- ceded by a boisterous north-east wind, which drifted the fallmg snow very much. It was on this day that the lowest state of the pressure occurred. The reporter has been particularly attentive to the barometri- cal oscillations during the above period. There have been 20 changes; that is, risings and falls; and the mercurial surface has risen and fallen nearly nine inches. The monthly mean is a little more than a general mean: the highest extreme was om the evening of the 8th, attended with an east wind and a little snow. The temperature during the first three weeks averaged 28°6° ; fourth week, 40°5°. On the morning of the Ist, and during part of the forenoon, the temperature was 19° below freezing ; and in some exposed situations, itis said to have been as low as 9°, or 22°, under freezing. On the breaking up of the frost about the 20th, the ice was noticed in some places about 18 inches thick; and where the ground was nearly free from reed a . a a ea sa) = Sigess! RCT aS AS we « \% q ra 2 : ae . ba \ 2 5s : Pao = : 9 : a8 5 0 oe 7 = s = e #8 . a ° or o : ’ S * i S 8 3 oF g 3 + =m t e = = ie 9 || © t t 4 ! { * + a \ +—t Gg ao —3 6 jae = SSS = ==: | : | if = Ss a= rd oe = 4 z T t H = = 4 + e pas es as ae i BE E = + 9 — ea) tars eas ie | [ | by t le r | ° 0 Can aes le S| 1 1s z = a + S- © \ a | ile lls = ie R = e S or || 1 = $ | e * | ++ ba a 1 3 < = = ie le SS = a) = ot a ict — - - 1M nal + — S| | N — ~ — — _ a z we ka =a i ia | | ALL, + | - Pal a} pai! | | eH | zi Fea tern F Mortage a [ 1 i i y ra | 4 4 f f | TEES lie Z | atest = m eed el Z w | ocl oe] ve[ze| | scl ee | es| cal vel osl@ | ota wil wll alae ols MOPUOT WS OF SZ HOT “95 Zee FUT yRION , ? UPI 7 O UBM) YP AY ) hy “i a7) “Yb 0 To 7 OC “Aun pie cenpenpuny yO apart SUOYONLIOG J UL. Cc yyy +4 fo PULy fe wW A) | ur AD WML —enee 1820.] Dr. Young on the Ligature of the Carotid Arteries. 427 snow, the frost penetrated about 14 or 15 inches below the surface. The weather was extremely foggy, and snow fell copiously, with a gradual rising of the barometer during the first rock, The mean daily temperature generally fluctuated between 20° and 30° till the 20th, when there was a great rise as already observed in the fourth week. The maximum of 53° took place about two o’clock on the 28th; in the course of the following night, the temperature fell to 34°, which marked the greatest daily variation for the month. The east and south-east have been the prevailing winds; the brisk winds were variable ; and the boisterous one from the north- east. ARTICLE V. On the Ligature of the Carotid Arteries as a Remedy for Deter- mination of Blood to the Head. By C. R. Young, M.D. Tue tying of the carotid arteries in order to moderate a determination of blood to the head seems at once so simple and obvious a remedy for this disorder, that 1 am inclined to think it must have suggested itself long ago to the faculty, and that some weighty reasons can be opposed against the employment of it; or that it has been already tried and rejected for special reasons. But as my reading and information are not sufficient to assure me of these facts, 1 venture to make the proposal with a due sense of my own ignorance and inexperience, and with every sentiment of respect and deference for the wisdom and knowledge of others. There is, I believe, in all or most graminivorous animals, which are forced to procure their food by grazing with their heads much lower than the rest of their bodies, a piece of structure in those arteries which corresponds to the carotids in the human species, by which the determination of the blood to the heads of these animals is prevented ; for considering the time which they employ in taking in their food, this affection could hardly fail to occur in them were no such apparatus furnished by nature. This consists in a convolution of the arteries, by which the impe- tus of the blood coming from the heart must be much broken. Now is it not reasonable to expect that if by any means we could imitate this device of nature, in cases of determination of blood to the head in the human species, that a beneficial result might be obtained? Let us suppose that one of the carotid arteries were tied (for as in many cases there is evidence of a much stronger determination to one hemisphere of the brain than to the 428 Dr. Young on the Ligature of the Carotid Arieries. [Junx, other, it might be sufficient to tie the artery of the affected side only), and that the blood was fcrced into a longer and more circuitous course by the anastomosing branches ; the arteries ard veins may have lost their natural tone and calibre, and eventually no doubt the anastomosing branches themselves would become expanded and enlarged so as to admit as much blood to the brain as formerly ; yet the tortuous course of the arteries would probably much diminish the vis a tergo, and deaden the impulse of the blood coming from the heart ; so that a powerfully co-operating remedy might be obtained in addition to those generally used. _ Of late, the operation of tying the carotids for aneurism has been successfully employed. I have not the advantage myself of knowing what phenomena have resulted from the operation with respect to the circulation of the blood in the head. As I believe it is a rule not to perform the operation until the anasto- mosing branches are sufficiently expanded to carry on the circu- lation, after the main artery has been closed, the case will not be in point; but probably much might be learned from an “attentive observance of such cases. It is very rash to form a priori conclusions upon the effects of operations which have never been performed, more especially where so delicate and mysterious an organ as the bram is concerned. It is likely, however, that if both carotids were tied even where an inordi- nate distension of the blood-vessels of the brain had before occurred, that the flow of blood would at first be so much impeded that the patient might fall mto the opposite extreme, and that fainting, or some affection arising from the presence of too small a quantity of blood in the head, would superyene. But this evil would only be temporary; and there are fortunately plenty of remedies for it much more efficacious than those now in use for the opposite affection. As most nervous diseases are supposed either to be connected with, or produced or ageravated by, a determination of blood to the head, I hope we may at length be enabled to discover some adequate means of sub- duing and keeping down these obstinate and untractable maladies. ) O8-1S| BE | $-GE| 6L-6S SB] 16) 88-62] L8-66 18-66|00-T| 09-81 1001] GF: 18| 0-69 SE 99 1-69] 9-19] €-69|0-8F 66 18-66) L8-66 | £9-0¢ 08 §-36) OL-8S/9T 68] L8-62 | | | | - L-§L) 1-L2)8-L9) 6 9b PLP 68,001) L-18} 9-78) 6-LL) L-38 0-97 F001 9-LL0- oF 09.01 £-CL| 0-6F 6F'86 6-FL) 0-19 66.001 1G) 9-69 9| 0-FS FF 86 6-1) Ob th LG 001 0-26 FE 96 | 90+ 1¥ 00-96 £395 16-68 c} 89-99 &6-6F ¢ §0:L9. 10-69 19-FL 68-99 G0-GL Z¢e-F9 | 6-89 96-09 &-F9 LL-9¢ 09-949, 0¢-6F 1 G0: 1G: 68 tf Ff) 06-9F) 9-66 00. a OL-9F OS-0F —_ co Seeaeawee, —_— aE LOL 0-61) ¢-64 ¢ no Pate eit FFL 16-68)! asy = £.99 §-69 62-621 08-62 (| 6-63) 26-66 8) 69-68 19-68 t 0: ag Cr LG 0-2F SG L6 +8 0-16 99.66 BAL bePL B-GL S18 SS { \ | W “UNIX? AY *xopul ayy Jo aSues uray “WNW "42019, § pur ‘g ‘9 je uvayy *sInoy FZ Ul ‘urd g je um pay ‘urd g ye wWnIpapy LES ‘urd g je wnipayy curd g Je wpa ‘ule g ye UINIpaTY *sInoy FS Ul UOTTBLIVA ISATIIH ‘ud g 7B wanIpayy ‘ord g ye WNIpI yy ‘ure g je WHIpaly B UONULLIVA 159) VAIN) *paqiiosap svovdg | "ure g 7 UINIpa HL MALAWOUDAN SONT AC YVALTNOWWVANL LHDIN ONV AVG 6¢-31| 188-62} | pLe 1S — 61-coloRel 86-111 188 “@2| 60-68) 09-08 -—— |-—-|-——_ omen £2 | 96-0 | F3L-63) 63-63) 02-08 13 | 18-0 |63L-63) 81-63] 60-08 aa | FO-E [3S9-63, 96-63, OF-0S cz | FG-0 |960-08 9-62) 0¢-08 £& | SIL | 190-08, $3-63, 98-08 a2 | 68-0 |LFO-08 LS+63| 93-08 61 | 89-0 |§26-6a! 09-63, 83-08 83 | 8-0 | 116-63) 9F-63| F3-08 Gt [CLL [661-63 60-63) $3-08 gt |GI-1 |126-62, P1-6%| 88-08 98 | 66-0 |#89-63, S1-6, 31-08 LE 1631 |E8L-63) 61-63, 8F-08 Sy Se ee | et lee | ae 5 | 98 = = a — 9 6 3 5 ° 3 5 I] 5 F 3 s as g E “UULANOUVA 0¢-83| 09-08 “S18I 4oy sy[nsay a "* F9QO1IG) «ener *ylag se ysnsny see eee Aine sees oune oo S>-- Ana eave ‘yudy SaaS Tit rereeraag Fees uDe “syIMOTY “61ST uv 9 ol *Su0'7] “a'Tl ‘foun TWILL *y40 dsory ‘huapooy 2y?, fo Ruojwasasgg, ay} yo qyday ‘GIL aX ay? ‘TA ATOILUY /6:F8 7b COMp UE *yOTAIANH JO ISAAK 1820.] Dr. Burney’s Meteorological Journal kept at Gosport. 429° “YON 18S lV c0S "wy moc 79190)0.10272 JT vp fo synsay 430 Dr. Burney’s Meteorological Journal kept at Gosport. [JUN¥, ‘oy Soyom m Gas | ERZESSSSSSTE | oD a pue SAous ‘yrey ‘wey | Soar hnrmRonans —7 qNocaows sOo7Te “39 |se52392232 SHH AHTHEMAAS ‘sayout ut uonviodeag S -——_ apa, PR SSS mSaSSS |! Sauyysry | POSH HBO = HOSS | « NeaSCCSOrar rons! SLOGJBUT [[CUIG Nw ‘SsMoqdiey.| SO eS eae Se aoe ‘sopey avuny | POV RSS Cones “SHEER | ee 38 ‘muajasurg | PS SCSSSSS ASR | 6 ik 23\10) 31115'12,49-80 |27:94 ‘Eipyeg | ZIP eTTOSH HS =) sie eee eee oo _ Pe ~ 7/58 32 25)18}121)16)12.31°26 |33°33 a “op ‘uley Foaosarnnae 1 a ‘soq | .* SHSoSS'S WEATHER. | ATMOS, PHENOM. Sie OS AG | =o i *kys WsedsaA0 UY | HIN OHOMBNtTSO 13 | a) = orl sk aaa * SEDO GRAN Sale | an cates See siege areas P| be = “IN | Ie “Ays Avaya y | ov oem ton St aan op =F OD 79 | | = SPO RKMNE SOE HADAID. =) SAQUIN | RRR Kaa Ae we oS = = 1NHOamaCKeDDANTAOlD! =) ssapensojnumg | = Feo SSAAH = | % | S Tomato arstNn-nnHo IO! oO 5 “sINUIND | ~— RA NRA Ig 1.3 2 = = ‘anjusg | NEMA ROMAHASS (S| & rmoen-ooors—-oolis!: = “SNILIPSOIND | RRANANANRWNYRR [S| =) = 2 >» it) e DOMMHDOMBDBEOH | O sujuunossig | Be coiiios GtGe eee sate fe] = BS =} = F acnoo—-onse snaitg | Sar Ee 3S iS8 |sivasSeuasees eis |.3° Jaquinu R07, z Ti ile oR C Ee Eat nt i. te) wn “759 Mo “won | S Nee nMeoNMne aN lo | oe = 4 oe A i) ae } . mlx =! ol = | 2M | wooornstoos || a a = as) sc | ees snide win | is gq Saat-yINOS | B'san oo om SAE ee Be = o fee oS i) & *ujno HORII eel od fot evo ion nog | Pai Snawtnor nee fo = SB ee) rel . = aca Racal bei) wig 2a] ysva-ynos | SOL Bone ana a le | © ) an i som ae eee nie: S “seq | canonnaeonre | ~ = = = A * apisioi nivale _ < rsva-qnu0N | NaN NweInn— lz | 6 : nis: =o “in ain Won | nn teos een a rf) = o . . . . . . = | tae Ne Bip Ne oS Boe iiss =e , © =“ *“sypUuOyY eS RS ee 2s = LE ae Sieh aa S ast a) rf a4am 4A = 1820.] Dr. Burney’s Meteorological Journal kept at Gosport. 431 ANNUAL RESULTS. Barometer. Inches. Greatest barometric pressure, Sept. 21. Wind, N.E, .. 30:50 Least ditto, April 16. Wind, S.....-+eseeeeeeeeeeee 29:09 Extreme range of the mercury. ...-.++++ stage pee Annual mean barometric pressure ...eeeeees saniad' si 29°881 Ditto ditto at 8, a.m. co. ccc cece ee ree etter en eeenes 29°870 Ditto ditto at 2, p.m. ceeseeeeesvercceereeeeeees o. 29-371 Ditto ditto at 8 p.m... sees eee eee M Dior els's ake Slate naiale 29°874 » Mean pressure for 190 days, with themooninN. declination 29°911L° Mean pressure for 175 days, with the moon inS.declination 29°851 Greatest range of the mercury in January ...-0esseee 1-290 Least range of the mercury in June... ++. see eee eeeee 0-680 Greatest variation in 24 hours in February...... aiedh <« -07Rae Least variation in 24 hours in September. .........--. 0°340 oes described by the rising and falling of the mercury 65°190 umber of changes caused by the variations in the weight of the atmospheric column ........e+eeeees aioe ate 280 Thermometer. Greatest.thermometrical heat, July31. Wind, N.E.... 83-00° Greatest cold, Dec. 29. Wind, TNS: sean oe ea Seats 15:00 Extreme range of the thermometer.......-+++++- nace OOM Annual mean temperature of the atmosphere.......+.- 52:10 Ditto ditto at 8 a.m. . .. cc evvccccccccecscccrcccses 50°53 Ditto ditto at 2 p.m... cesses cee eeeereeereeceee 0 ee ee Ditto ditto at 8 p.M.... esse ee eesere eee Se one ee Greatest range in October. ......++eeee rece seer cree 39°00 Least range im January amd) Miarciatavate testers) eieiotetensteloys 25°00 Annual mean range ...- sees eee ee ee eeees Ee LPTs 32°33 Greatest variation in 24 hours in June. ....ee-.ee++2- 30°00 Least variation in 24 hours in January. ....++eeeeeee » 17-00 De Luc’s Whalebone Hygrometer. Greatest humidity of the atmosphere several times. .... 100-0° Greatest dryness of ditto, Sept. 1. Wind, WY x caleiai is 39°0 Extreme range of the index....---+-+-, SET Og 61-0 Annual mean state of the hygrometer at 8 a.m.......- 76:3 Ditto ditto at 8 p.m... . eee ee cece eeeeeeees sie. 6 abote'e oe (eG). Ditto ditto at 2 p.m.........6-- a iebajdleiel trahe.s\e pole sats 67:8 Ditto ditto at 8, 2, and 8 o’clock . ws... ee eeee er eeeres 73°7 Greatest mean humidity of the atmosphere in Dec. .... 81:7 Greatest mean dryness of the atmosphere in May....-. 668 432 Dr. Burney’s Meteorological Journal kept atGosport. [June, Prevailing Winds Days. From north to north-east. .......... aves oar tite Wiss «} 36 bee 4514 From north-east to east. ......0. 2c eee KOM! one" ichere 24 Brom cast to south-east...) Di Sie bere eee nie's Send aca aah ee Pear soiiizedst to south. 3.0.6 ors oc ie a Dida eole s wtew be oe 29 Peony sonthito south-west: 2.06666 00 bl od oe 35 From south-west to west. ...cccccceccccseces Sh h Sah 2 Sas From west to north-west... ..cc0..eceeedeeds ee. $8 oT From north-west to north. ...... BI2% SEG OAE renee 60 365 Clouds, agreeably to the Nomenclature. Days- ee Pai awit iboats > Oa ood hie blige apoee «eo 209 Cmrocumulas: acc. seeeeelec. Cis ioe lenistinsigd i #488 Cerortratusy weiss cee os Jb CUS ios ieee eine Paraselene, or mock-moons. .......60+4+ j Mea etek we REE ERAGON 649 dao wsnaid bled asemolet palit ob esigdt nee Lunar halos .......... OEE ee eRe re ee, 25 Rainbows, perfect . ...... Ps por see Lee Malcesine 18 Small meteors, commonly called shooting stars. ........ 121 Aurora Borealis, Oct. 17, in the evening. .......... 0005 1 Lightning, days on which it has occurred...... OE EMG fi! Witmader, UittO-ditbe 16. kh cs ane slp iiasa' aie sieht arse = 0-460 This loss I ascribe to oxygen. These quantities converted into volumes become : Cappon. ts oN tote ele 4 cubic inches. Hydrogen. J... aise ss ese 1 Oxygen ...... es apersees 12 This is equivalent to 4 atoms carbon. .. = 3:000 or 8 atoms carbon. .. = 6-00 1 atom hydrogen.. = 07125 2 atoms hydrogen. = 0°25 3 atoms oxygen .. = 3°000 6 atoms oxygen... = 6:00 6125 12:25 470 Scientific Intelhgence. [June, So that by the heat two atoms of carbon and nine atoms of hydrogen are removed, while the atoms of oxygen are doubled. From this we see that a considerable proportion of oil must have been driven off by the heat. VIL. Morphia. I find the easiest method of obtaining morphia in a state of purity is the following: Into a strong infusion of opium pour caustic ammonia, Separate the brownish-white precipitate by the filter. Evaporate the infusion to about one-sixth of its volume, and mix the concentrated liquid with more ammonia. A new deposit of impure morphia is obtained. Let the whole of this deposit be collected on the filter, and washed with cold water. When well drained, pour a little alcohol ‘on it, and let the alcoholic liquid pass through the filter. It will carry off a good deal of the colouring matter, and very little of the morphia. Dissolve the impure morphia thus obtained im acetic acid, and mix the solution, which has a very deep-brown colour, with a sufficient quantity of ivory black. This mixture is to be fre- quently agitated for 24 hours, and then thrown upon the filter. The liquid passes through quite colowless. Ifammonia be now dropped into it, pure morphia falls in the state of a white powder. If we dissolve this precipitate in alcohol, and evaporate that liquid slowly, we obtain the morphia in pretty regular crystals. It is perfectly white, has a pearly lustre, is destitute of smell, but has an intensely bitter taste, and the shape of the crystals in all my trials was a four-sided rectangular prism. When one grain of pure morphia is passed slowly through red- hot peroxide of copper, it is converted entirely into carbonic acid — and water. The water obtained in four successive experiments was always 0°5 gr. The carbonic acid gas amounted to 3°58 cubic inches, supposing the barometer to stand at 30 inches, and the thermometer at 60°. Now 0°5 gr. water contains. .... 0°0555 gr. hydrogen 3°58 cubicinches of car. acid 0:4528 gr. carbon Patek oe ee eee There is wanting 0°4917 gr. to make up the original weight of the morphia. This deficiency must be owing to the morphia containing a quantity of oxygen equal to it in weight. It follows, from the preceding data, that the constituents of morphia are as follows : Hydrogen. .:.¢scaseee+>s 00550 Carbon). -.bs.< ce nnes es ve O528 ORBEA: ion.4n eva gene e-ae OFRKG 1:0000 Now when these weights are changed into volumes, they amount very nearly to 1820.) Scientific Intelligence. 471 18 volumes hydrogen, 24 volumes carbon, 10 volumes oxygen. This is equivalent to 18 atoms hydrogen. .... 24 atoms carbon. ...... 20 atoms oxygen. ...... 225 sessee 5°59 18:00 ...... 44:72 20°00. aia. see's to OO cs 40°25 100-00 So that, if the preceding analysis be correct, the weight of an integrant particle of morphia is 40°25. . The reader will easily perceive that we might consider this substance as a compound of only half the preceding number of atoms, or of S-atoms hydrogents:, ...%ssiedaaaawetiee’ GeO 12 atoms carbon eeoetoeoreeeereseees — 9-000 10 atoms oxygen..... ase nase ehorelg = 10-000 20-125 On that supposition the equivalent number for it would only be 20°125. Perhaps this last estimate may be the most correct; but the analyses of the salts of morphia, published by Robiquet and by Pelletier and Caventou, give an equivalent number for morphia not far short of 40. This is my reason for considering it as a compound of 62 atoms rather than of 31; either of which is equally indicated by the analysis. 1X. New Projection of the Sphere. By Capt. J. Vetch, R. E. In this projection the globe is supposed to be inscribed in a cylinder, the axes of the globe and cylinder being at right angles to each other, and their surfaces, therefore, coinciding at a meri- dian. The eye is supposed to remain at rest in the centre of the rlobe, and each point in the earth’s surface is transferred to that of the cylinder by a right line passing from the earth’s centre through that point. The cylinder being then unravelled, a view of the earth is obtained on a plane surface. A sketch of the earth’s surface upon this projection has been published by the author, accompanied by a short account of its principles. X. Excrement of the Chamaleonis Vulgaris. By Dr. Prout. A small portion of the excrements of this animal was given me for examination by Dr. Leach. It consisted partly of a fine powder, of a bright lemon-yellow colour, and partly of lumps composed of the same powder loosely agglutinated. On exami- nation, it was found to be chiefly composed of the lithate or urate of ammonia, and a little colourmg matter. Hence, as indeed I had expected, its composition was precisely the same as that of the urinary excrement of the boa constrictor and lizard tribe, as previously ascertained by Dr. J. Davy, and myself. The food of this animal is said to consist of the lumbricus terrestris, and the larvee of the tenebria molitor. 472 Col. Beaufoy’s Magneticai [Jowr, ArticLe XI. Magnetical and Meteorological Observations. By Col. Beaufoy, F.R.S. Bushey Heath, near Stanmore. Latitude 51° 37! 44-27” North. Longitude West in time 1/ 20°93”. Magnetical Observations, 1820. — Variation West. Morning Observ. Noon Obsery. Evening Obsery. Month, Hour. Variation. | Hour. Variation. Hour, | Variation. April 1] 8h 35’| 24° 99’ 59” Ih 15’| 24° 38! 49") — —') _o —! _w# 2} 8 40) 24 30 28/]*1 35/24 38 12/ 6 30/24 32 52 3] 8 35|24 98 33| 1 05] 24 42 23);— —|— — — 4| 8 40; 24 32 24 1 20} 24 39 41 6 30 | 24 28 12 DiLvSpacoieeds sky OS) ds 35 | 24 AT. 20 17 6 Sb Rade ean rey 6|'"8' 45 | 24 32° 00) 1.25) 24 AL 27} 6 30) 94 26 32 Mies Sat| "24% 30. 06 1 25/24 40 41 6 25 | 24 33 42 8; S 40| 24 35 13 1 15] 24 41 29;— —|;— — — 9| 8 40| 24 32 00; 1 30} 24 38 45] 6 30| 24 32 38 10; 8 40 | 24 30 44) 1 20] 24 38 JL} 6 25/94 33 27 lj 8 05/24 29 45);— —|— — —/— —/|— — — 12| 8 45] 24 29 44 1 .15 | 24 40 09 6 30| 94 32 18 13) 8 35] 24 31 21) 1 20| 24 41 04] 6 35) 24 32 47 14} 8 40) 24 29 30| 1 25] 24 42 33;— —/— — — 15} 8 35| 24 29 23] 1 25|24 41 44) 6 45) 94 33 17 16| 8 35) 24 30.56) 1 35] 24 40 03) 6 05 | 94.34. A5 17) 835) 24 28 04/ 1 35) 24 40°55) 6. 55 |'94 38" 02 18; 8 35/24 31 10})-— —]|— — —}— —|— — — EO)|) (S035 |) 24° 2901050) N25.) 24 AB. 385) 6 “90 oa San ihe 20} 8 35 | 24 33 36 1 20) 24 42 54;— —|}— — — 214" 8) AS 124.29) 55 1 20| 24 40 36 6 50] 24 32 58 22) 8 35 | 24 30 33 1 20 | 24 41 36 6 45 | 24 33 57 23) 8 45] 24 30 26 | 1 30 | 24 40 28 6 50} 24 33 OA 24) 8 40] 24 30 56 1 25} 24 39 00;— —|{— — — 25) 8 35 |24 30 58 1 25 | 24 39 03 6 55|24 33 40 26) 8 40] 24 29 12] 1 25/24 40 00; 6 25] 24 31. 59 27| 8 35) 24 30 28 | 1 25); 24 42 22;— —;- — — 28) 8 40] 24 32 33 } 20} 24 37 44 6 50 | 24 32 32 29): 8 35) 24 29 05 1 20} 24 37 38 6 55 | 94 33 05 30) 8 35 | 24 29° 32 1 50/24 42 04! 6 55] 94 29 10 Mean for | : | the ‘ 8 37 | 24 30 38 1 24) 24 40 29 6 37/24 31 58 Month, | 1820.] and Meteorological Observations. 473 Meteorological Observations. Month. | Time, | Barom. | Ther. | Hyg. | Wind. {Velocity.|Weather.| Six’s. April Inches. Feet. Morn,...| 29°554 | 439} gl1° WSWw Foggy 383 4 Noon....| 29-488 | 55 55 W byS Fine 552 Even . — a a — _ : Aah Morn,...| 29°609 | 49 72 W by S Cloudy = 2! Noon,...| 29°605 | 60 63 WNW Cloudy 604 Even ....| 29°623 55 65 WwW Fine ‘ A924 Morn,...| 29°729 | 53 A9 NE Cloudy e 3 Noon... SOR acetic, 59 60 Var, Cloudy 593 Even....| — _— — - — : 39 Morn....| 29-493 | 46 60 SE by E Fine nk Noon....| 29-444 59 Al SSE Very fine 602 Even ....| 29°400 53 AY EbyS Fine 432 Morn....} 29°344 | 51 49 SE Very fine ‘ 2 x} Noon....| 29°303 &2 43 SSW Cloudy 641, Even ....| 29188 | 58 | 48 | SW byS Very fine bas ‘ ¢ |Morn....} 28°936 48 8T SW Rain 6 Noon....| 28°910 50 63 W byS Showery | 514 Even....| 28°910 3 70 Wsw Showery 31 Morn... .| 28°980 47 63 WwW Fine } Noon....| 28-984 A5 54 WobyS Sn.show,.| 472 Even....| 29°000 4l 68 SW Showery 35 Morn....| 28-893 Al 66 SSW Fine j Noon....| 28°805 | 49 60 Ss Cloudy 501 Even ....| 28°757 _— 7 E Rain : rr Morn....| 28°788 Al 87 NW Rain. 0 Noon. ...| 28°880 | 48 63 WNW Cloudy AQs Even ....| 28°954 | 44 66 Ww Showery ‘ 33 Morn...., 29-013 | 40 79 SSW Cloudy 10 Noon....| 28°940 | 45 80 SSE Rain AT Even ....| 28-878 A6 8T SSW Rain ‘ 45 Morn....| 28°990 AT 85 SSW Cloudy 114 [Neon vae| > — — = _ — 56 Even....| — _ _ — — ; Ade Morn....| 29°272 AQ $2 SW Cloudy £ 2} Noon....| 29:°323 | 59 64 Var. Fine 56 Even....| 29°363 | 52 | 72 SSE Showery nie | Morn....| 29:404 | AT | 83 NE Fog = 134 |Noon....} 29-400 53 71 Var. Rain 53 Even....| 29-344 49 80 NE Rain 45 j Morn....| 29133 | 46 | 90 | NEbyN Rain , 144 |Noon....| 29-127 51 15 NNW Showery| 52 Even....! 29-146 — 83 NW Showery 31% Morn.. 29-309 45 61 NW Clear t 13) Noon....| 29-335 50 59 Var. Showery| 54 Even ....| 29°395 A8 54 NW Fine 38 Morn....| 29°583 A6 58 SW Fine ' .} Noon....| 29°609 58 56 WNW Fine 58% Even ...} 29°635,| 55 60 NW Fine AG Morn... .} 29-164 56 58 W Very fine ‘ ~ ta Noon....| 29°762 63 55 NNE Very fine} 652 &|Even....| 29°T43 58 61 NNE Very fine 49 Morn....| 29 712 55 64 ENE Very fine ‘ | Noon —_ --- — — Very fine| 65 Even _ a co —_ Very fine a a 474 Col. Beaufoy’s Meteorological Observations. [June, Month. | Time. | Barom. | Ther.| Hyg.| Wind. |Velocity.;Weather.|Six’s. April Inches. Feet. Morn....| 29°705 58° NE Very fine} 483 192 |Noon,...| 29°674 54 Var. Fine 672 Even....| 29°633 58 WNW Fine 4G Morn,...| 29°673 56 NW Very fine ‘ ao} Noon,...| 29°713 54 NW Cloudy 613 Byen.c..| | — — — = 5 Morn, ...| 29°820 54 NNE Clear ‘ ‘ ay Noov,.,.| 29°797 50 Var. Verytine| 634 Even....| 29°795 55 Eby S Very fine 4G Morn....| 29°892 56 Eh Clear : at Noon....| 29°903 53 E Clear 63 Even ....| 29°892 56 Ehy N Clear 40 Morn,...| 30°013 58 ENE : Clear ‘ 2) Noon....}| 30°019 50 ENE Clear 63 Even ...| 30-039 57 | NEby E Clear 40 Morn... .| 30°053 64 NNE Very fine ‘ at} Noon,...| 30°053 52 NE Very fine| 63 Byen... .|!) = = = == 38 Morn....| 29°958 64 NE Fine ‘ 25} Noon....| 29°900 53 NE Clear 60 Even....| 29°849 57 NE Clear 40 Morn,...| 29°489 5T WSW Very fine ‘ ao} Noon....| 29°338 52 |NW by W Cloudy 62 Even....| 29°254 58 NW Rain Morn, ...| 29*235 81 | NbyE Rain ‘ = 215 |Noon....| 29°321 65 NE Showery | 43 Even...) = _ = _ Morn... 29-528 51 | Nby W Cloudy |¢ 36 28< |Noon....| 29°546 52 Var. Very fine} 53 Even....| 29°547 54 SW Very fine S Morn....| 29°615 57 | SW by W Very fine 36% 294 |Noon....| 29°622 50 SSW Fine 574 Even....| 29°624 53 W by S Cloudy ae Morn....| 29°696 70 | NW Showery ‘ 22 804 |Noon....| 29°739 53 NNW Fine 58 Even....| 29°780 53 N Fine Rain, by thé pluviameter, between noon the Ist of April, and noon the Ist of May, 1°505 inch. The quantity that fell on the roof of my observatory, during the same period, 1-495 inch. Evaporation, between noon the Ist of Apml, and noon the lst of May, 3°75 inches. 1820.] Mr. Howard’s Meteorological Table. 475 ArTICLE XII. METEOROLOGICAL TABLE. BAROMETER,| THERMOMETER, Hygr, at 1820. | Wind. | Max.| Min. | Max. | Min. | Evap. |Rain.|] 9 a.m, Ath Mo. April 1S W/{30°1030°04} 62 45 87 2IN W/30:2330:10| 66 49 74 31 N_ |30°23)30°12} 64 36 79 A\S E/30°12/29°88} 65 31 73 5} Var. |29°88/29:41} 72 45 21 68 57 6|S W/)29:44)29°36| 56 32 — 7S W/29:57|29°41| 52 31 —_ 8IS W/)\29:411/29:27| 54 44 — QIN W/(29-46|29:27| 52 28 — E/29:44/29°37| 52 46 —_— W/29°78/29:44| 59 45 45 E|29:91/29°78| 59 44, — 13IN __E/29°88/29-68] 53 45 —| 32! 93 ¥/29°84/29°'71| 55 39 —_ W/30°12/29'84| 59 30 20 16/S W/30°27/30:12] 63 43 — 30 47 17IN W/(30'22/30'18} 68 39 82 18|S E|30:20/30'14| 69 37 83 19IN W/\30:18/30°14] 72 44 RX0) 20|N W/)30°31/30°18} 65 35 (eee e 21\IN W/(30:39!30°31| 68 32 74 2} E 1|30°51/30°39} 65 34 72 23) E 30°53)30°51 65 35 — 69 24\N )30°51|30°47| 66 36 — 73 25\N _—-E/30°47|30:03} 63 29 50 72 26| W_ |30:03/29-77| 69 40 —j} 28) 68 27IN _E|30°07/29°92| 46 36 — 74 28} N_ (|30:15'30°07| 52 34 oe 67 |O 29/5 W/1|30°21130°15| 60 37 — 68 30/N W/({30°36/30:21| 63 28 46 | — 75 — $0°53'29-27| 72 28 | 2:95 1581 96—671 The observations in each line of the table apply to ‘a period of twenty-four hours, beginning at 9 A. M. on the day indicated in the first column, A dash denotes, that the result is included in the next following observation, 476 Mr. Howard’s Meteorological Journal. [June, 1820. REMARKS. Fourth Month.—1. Cloudy: windy, 2. Cloudy. 3. Calm: close: overcast. A. Cirrus: Cirrocumulus: clear. 5. Cirrus: Cirrocumulus. 6. Cloudy: showers. 7. Hoar-frost : some gentleshowers during the day: a few flakes of snow, p.m. 8. Hoar-fros:- cloudy: showers. 9. Showery: fine. 10. Windy morning: heavy squalls, with showers, most of the day: some thunder clouds, anda rainbow, p-m. ll. Showery. 12. Overcast. 13, 14. Rainy. 15. Fine: Cirrus: Cirro- cumulus, 16—24, Fine, with Cirrus at intervals. 25, 26. Cloudy. 27. Some gentle rain this morning: the wind strong and cold from N E. Theswallows made their appearance about five this morning in great numbers, 28,29. Fine. 30. A gentle shower about nine, a, m. RESULTS. Winds: N,2; NE, 5; NW,8; W,1; SW,7; SE,4; E,2; Var.1. Barometer: Mean height .Forithe month, oo .50... 6% sheeeesccsvceetevens 29 954 inches, For the lunar period, ending the 6th, ............. 29:°974 For 13 days, ending the 10th (moon south) .. ,.... 29°790 For 14 days, ending the 24th (moon north) ....... 30°127 Thermometer; Mean height For the month....... wneweeececunewas Sie\vinole ais ave $40 SOOe For the lunar period, ending the 6th, ......... ... 48°258 For 30 days, the sun in Aries. . .......... Sm elevies « “AUTOM Hygrometer: Mean for the month . .....0....-sccecescocsseccne- 10°9 Eyaporation,.\. .c< QU quia OY Safa, aoa Onn He alae 7 Nay ty ee ey a mS ty th ada ea sors to oh soul, for »\ ~e 0 ee or = 9 ix Be ee iq . tris Ray talent eh) biadaied aeueeae 0 ain a9) rs ry ee Ns 2 fait: wadl intend laoPeeilcie oul We ate fawn 1 ij dee at fev fet Tip. stirhjleety DA aie Th em he a 2 dese }4 ere ger a G oe yo hindwe le ‘dS qargot ad dew | ae ‘ .. has ghneantin® “aye fe) - ie. 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