544 



Mr, Taylor on Four Dogmas 



[Jan. 1, 



Delamcfhcric inferred, tliat the oxy<jen 

 exppled to the contact of water, was fle- 

 CDnijjofcd, and a portion of it converted 

 into azote. 



That the hydrogen, expofed in like 

 inaiiner, was alfo chanjj;ed and a part of 

 it converted into azote. 



That the azote expofed to water, be- 

 came anieli(jrated, and a certain quantity 

 of it was cliatif^ed into oxygen. 



IIurnl)ol(lt and Gay-Luflac, on the con- 

 trary, conclude that the oxygen expoftd 

 to the action of water, is abforbed by it, 

 and diiplaces the azote, which afceuds 

 jnlo tlie bcU-giafs. 



Tiiat tlie hydrogen, expofed in like 

 manner, is alfo abforbed by the water, 

 and difplacci the otlitr gafes which 

 afcend into the bell. 



That the azoie, expofed to the con- 

 tact of water, is abforbed V.y it, and dif- 

 places the oxj'gcn v liich afcends into the 

 bell. 



It remains for impartial chcmifis to de- 

 cide, v.hich of thefc opinions is tnoft coti- 

 fonnahie to truth. But this quoftion in- 

 volves another, viz. whether ail tliefe 

 gafes arc elementary indccompofahle fub- 

 ftances, as well as all other elementary 

 iubftances of modern chetniftry? 



The obfervations of Humboldt and 

 Gay-Luliac, terminate with a table cx- 

 hibiiing the analylis of atmofphinc air, 

 {luring 30 days, from the 10th IS'ovem- 

 ber, to the 22(1 December. The tcmpe- 

 ratijic had, durins; this period, varied from 

 IQP of the centigrade thermometer, to 

 4. 1. 



- Wind, rain, and fno.v, had all fuccef- 

 fivrly occurred in the courie of thofe ex- 

 periments. The quantity of oxygen pi-c- 

 fent, was always 0. 21. It was, however, 

 at one, 0. 21.' 2, and at another 0. 20. 9. 



From tliefe facts, it may be concluded, 

 that atmoipheric air contains : 

 Oxygen . _ _ _ o. GIO 

 Azote - - - - 0. 783 



Hydrocen - - - - 0. 003 

 Carbonic Acid - - - 0. 004 

 Yours, Ike. A. II. 



To the Editor of tlic Motiihlt/ Miigazine. 



Slli, 



AS it is ray intention, in the General 

 Introduction which will be prelixed 

 to my truiilli^tion of the whole of Arif- 

 totle's Works, to fliow, from the moft une- 

 quivocal evidence, tliat his philofophy 

 has noi been undcillood for many cen- 

 turies; the following olifcrvations in the 

 interim, on four very important dogmas 

 of his phyfiology, may not perhaps be 



imacceptable to the phiiofophical part of 



your readers. 



In the iirll place, in the beginning of 

 his difculbon about a celeftial body, in 

 his Treatifc on the Heavens, wifhing 

 to fliow that it is perpetual, he previoully 

 evinces that it is dili'erent from tlie four 

 elements. But he frarnes the dcmonftra- 

 lion of this from the multitude of na- 

 tural motions. For if natur.tl things are 

 natural from having nature, (but nature is 

 a principle of motion), the demonftratiou 

 from natural motion, is at the fame time, 

 from thing"* more evident, as being from 

 energies; and at the fame time is fron; 

 things more peculiar, as being from 

 caufes. But in order to the demonftra- 

 lion from motions, he pre-afl'umcs fix 

 things, vi,'. that there are two fimjile mo- 

 tions, that which is in a circle, and that 

 which is in a right line ; that a fimple 

 motion, is the motion of a fimplc body; 

 that of a innple body, the motion is fim- 

 ple ; tliat there is one natural motion of 

 one iliing; that one motion is contrary 

 to one; and that the heavens are circu- 

 larly moved. Thefo hypothefcs alfo, are 

 mentioned by Plotinus, in his Treatife 

 on the World; for being delirous to 

 fliow, according to Plato, the perpetuity 

 of the heavens, he fays, the demonftra- 

 tion of this will be attended with no la- 

 bour to Ariftotle, if his hypothefcs about 

 a fifth body are admitted, meaning the 

 above mentioned. For thcfe being ad- 

 mitted, the perpetuity of the lieavenly 

 bodies neceflarily follows. 



It is rcquilite to obfen'e, however, that 

 by (imple bodies, Ariftotle means thofe 

 which contain a principle of motion ac- 

 cording to nature. For animals and 

 plants have alfo a principle of motion, 

 yet not according to nature, but accord- 

 ing 10 foul ; and hence they are different- 

 ly moved at different times. For com- 

 pofite liodiesdo not remain in the poffef- 

 lion of limilar parts, but alfo receive or- 

 ganic parts; as having a foul which nfcs 

 the body as an inftrument. But nature 

 is the ]n-inciplc of the motion of afimple 

 body ; and hence bodies which alone 

 polVefs jiatuie, have alone a fimple mo- 

 tion. 



The following argument, employed by 

 him, to Ihew that the heavenly bodies are 

 not moved by vinhnco, appears to me to 

 poffefs an invincible Ihength. If a celef- 

 tial body is moved by violence, it is not 

 moved naturally ; and if it is not moved 

 naturally, it is moved contrary to nature. 

 Bat tlie motion, which is contrary to na- 

 ture, is polterior ^o tliat ^Yhich is accord- 

 ing 



