CHEMICAL TRANSFORMATIONS. 



91 



Si.iall quantity of the juice of grapes in the 

 act of fermentation, added to a large quan- 

 tity of the same fluid, which does not fer- 

 ment, induces the state of fermentation in 

 the whole mass. So likewise the most mi- 

 nute portion of milk, paste, juice of the 

 beet-root, flesh, or blood, in the state of 

 putrefaction, causes fresh milk, paste, juice 

 of the beet-root, flesh or blood, to pass into 

 the same condition when in contact with 

 them. 



These changes evidently differ from the 

 class of common decompositions which are 

 effected by chemical affinity; they are 

 i chemical actions, conversions, or decompo- 

 jsitions, excited by contact with bodies al- 

 vready in the same condition. In order to 

 Form a clear idea of these processes, analo- 

 gous and less complicated phenomena must 

 previously be studied. 



The compound nature of the molecules 

 of an organic body, and the phenomena 

 presented by them when in relation with 

 other matters, point out the true cause of 

 these transformations. Evidence is afforded 

 even by simple bodies, that in the formation 

 of combinations, the force with which the 

 combining elements adhere to one another 

 is inversely proportional to the number of 

 simple atoms in the compound molecule. 

 Thus, protoxide of manganese by absorp- 

 tion of oxygen is converted into the sesqui- 

 oxide, the peroxide, manganic and hyper- 

 manganic acids, the number of atoms of 

 oxygen being augmented by J, by 1, by 2, 

 and by 5. But all the oxygen contained in 

 these compounds, beyond that which belongs 

 to the protoxide, is bound to the manganese 

 by a much more feeble affinity; a red heat 

 causes an evolution of oxygen from the 

 peroxide, and the manganic and hyperman- 

 ganic acids cannot be separated from their 

 bases without undergoing immediate decom- 

 position. 



\ There are many facts which prove, that 

 .'he most simple inorganic compounds are 

 ^ also the most stable, and undergo decompo- 

 / sition with ffre greatest difficulty, whilst 

 those which are of a complex composition 

 yield easily to changes and decompositions. 

 The cause of this evidently is, that in pro- 

 portion to the number of atoms which enter 

 into a compound, the directions in which 

 their attractions act will be more numerous. 

 Whatever ideas we may entertain regard- 

 ing the infinite divisibility of matter in 

 general, the existence of chemical propor- 

 tions removes every doubt respecting the pre- 

 sence of certain limited groups or masses of 

 matter which we have not the power of divid- 

 ing. The particles of matter called equiva- 

 lents in chemistry are not infinitely small, for 

 they possess a weight, and are capable of 

 arranging themselves in the most various 

 ways, and of thus forming innumerable 

 compound atoms. The properties of these 

 compound atoms differ in organic nature, 

 not only according to the form, but also in 

 many instances according to the direction 





and place, which the simple atoms take iu 

 the compound molecules. 



When we compare the composition of 

 organic compounds with inorganic, we are 

 quite amazed at the existence of combina- 

 tions, in one single molecule of which, 

 ninety or. several hundred atoms or equiva 

 lents are united. Thus, the compound atom 

 of an organic acid of very simple composi- 

 tion, acetic acid for example, contains twelve 

 equivalents of simple elements ; one atom 

 of kinovic acid contains 33, 1 of sugar 36, 

 1 of amygdalin 90, and 1 of stearic acid 138 

 equivalents. The component parts of ani- 

 mal bodies are infinitely more complex even 

 than these. 



Inorganic compounds differ from organic \ 

 in as great a degree in their other characters \ 

 as in their simplicity of constitution. Thus, 

 the decomposition of a compound atom of 

 sulphate of potash is aided by numerous 

 causes, such as the power of cohesion, or 

 the capability of its constituents to form 

 solid, insoluble, or at certain temperatures 

 volatile compounds with the body brought 

 into contact with it, and nevertheless a. vast 

 number of other substances produce in it 

 not the slightest change. Now, in the- de- 

 composition of a complex organic atom, 

 there is nothing similar to this. 



The empirical formula of sulphate of 

 potash is SKO 4 . It contains only 1 eq. of 

 sulphur, and 1 eq. of potassium. We may 

 suppose the oxygen to be differently distri- 

 buted in the compound, and by a decompo- 

 sition we may remove a part or all of it, or 

 replace one of the constituents of the com- 

 pound by another substance. But we can- 

 not produce a different arrangement of the 

 atoms, because they are already disposed in 

 the simplest form in which it is possible for 

 them to combine. Now, let us compare the 

 composition of sugar of grapes with the 

 above: here 12 eq. of carbon, 12 eq. of 

 hydrogen, and 12 eq. of oxygen, are united 

 together, and we know that they are capa- 

 ble of combining with each other in the 

 most various ways. From the formula of 

 sugar we might consider it either as a hy- 

 drate of carbon, wood, starch, or sugar of 

 milk, or farther, as a compound of ether 

 with alchohol or of formic acid with sachul- 

 min.* Indeed we may calculate almost all 

 the known organic compounds destitute of 

 nitrogen from sugar, by simply adding the 

 | elements of water, or by replacing any one 

 of its elementary constituents by a different 

 substance. The elements necessary to form 

 these compounds are therefore contained in 

 the sugar, and they must also possess the 

 power of forming numerous combinations 

 amongst themselves by their mutual attrac 

 tions. 



Now, when we examine what changes 

 sugar undergoes when brought into contact 

 with other bodies which exercise a marked 



* The black precipitate obtained by the action 

 of hydrochloric acid on sugar. 



