EffeB of Sulphuric Acid on Vegetable Matter. 3S7 



water, (ince it-is, In a word, extremely diluted, it is evident that the water it has acquired 

 could not have been formed but at the expence of the principles of the vegetable, and that it 

 contains the weight which is wanting to the carbone and acetous acid to reprcfent the whole 

 of the vegetable matter fubmitted to experiment. For it is very certain that an a£lion 

 perfectly the fame, and a refult accurately identical, takes place in clofed vefTels, as well as ia 

 fuch as are open ; and that the water which faturatcs the fulphuric acid does not come from 

 the atmofphere. We are therefore forced to conclude, from this examination, that the ve- 

 getable fubftance treated with the concentrated cold fulphuric acid, has fufFered a decom- 

 pofition or analyfis by feparating a portion of its carbone nearly pure, and that another p:irt of 

 carbone has united with hydrogene and oxygene to form the acetous acid, at the fame time 

 that a fecond portion of oxygene has united with a fufficient quantity of hydrogene to form 

 the water which dilutes the acid. All thefe changes in the vegetable fubftance are therefore 

 made at the expence of Its own proper principles. Nothing has come to pafs but a cliangc 

 of equilibrium between them, a feparatlon and unequal combination of their component 

 parts, which produce the three new produ£ls obtained. 



In what manner does the concentrated fulphuric acid determine tliis change of equili- 

 brium ? How can it convert an homogeneous organic matter into acetous acid and coal ? 

 What is the force or forces whofe energy or concurrence deflroys the conneftion which 

 united the principles of the vegetable fubllance, while it has no Influence on the fulphuric 

 " acid? A fingle argument well applied, from the refult of experiments, will lead us to the 

 folutlon of this problem, Since a vegetable fubllance requires a new equilibrium of prin- 

 ciples after the total action of the concentrated and cold fulphuric acid, and remains in the 

 triple ftate of carbone, acetous acid, and water, at which period the fulphuric acid has 

 become much lefs denfe and concentrated than before; — we muft conclude, that the affinity 

 of this acid for water, as well as that of the oxygene for hydrogene and carbone, at the fc- 

 ♦eral proportions required to form vinegar, prevail over the attratlions which held thefe tJirec 

 principles united in other proportions under the original form of homogeneous vegetable 

 matter. But, in this new fum of ele(Slive attraftions, the only caufe which determines the 

 change that takes place is the afBnity of the fulphuric acid for water, of which the prin- 

 ciples do not unite nor the compofition take place, till the moment at which this affuiity 

 a£ls. Wlien once this tendency of the acid for water is fatisfied, the equation between 

 the feveral principles is efFeded, an equilibrium is eftablilhed, and no further alteration 

 follows. 



It feems, however, at firfl fight, that the imagination refufes to admit, in the fulphuric 

 acid, an alTuiity for a body which does not cxill completely formed, or to conceive the 

 formation of the water as rcfulting from the attraction which the acid exerts upon it, though 

 it do not yet exifl; in the vegetable matter, but In its principles. But whatever repugnance % 

 refult of this kind fcems at firll to produce. It does not appear lefs certain, fmce it is evi- 

 dent, ns matter of fadt in this experiment, that the acid originally concentrated become* 

 feeble and aqueous; that the water did not txifl: ready formed in the vegetable matter 5 

 that it was not taken from the atmofphcric air ; and tliat, when once the acid has become 

 diluted, every fubfequent a£tion ceafes. Thefe four points are equally edvibliihed, and 

 there can be no doubt of their certainty. Befides which, a great number of fa£ls are ac 

 prcfenc well known to chcmilts, which compel them to admit fuch alEuilics as are pro- 



3 IJ 3 dudiye 



