CHEMICAL TRANSFORMATIONS, 



acid (04 H3 O3=C3 H3 O + CO2,) and 

 meconic acid into carbonic acid and kome- 

 nic acid; whilst by the influence of a higher 

 temperature,, the latter is further decomposed 

 into pyromeconic acid and carbonic acid. 



Now in these cases the carbon of the bo- 

 dies decomposed is shared between the oxy- 

 gen and the hydrogen ; part of it unites with 

 the oxygen and forms carbonic acid, whilst 

 the other portion enters into combination 

 with the hydrogen, and an oxide of a carbo- 

 hydrogen is formed, in which all the hy- 

 drogen is contained. 



In a similar manner, when alcohol is 

 exposed to a gentle red heat, its carbon is 

 shared between the elements of the water 

 an oxide of a carbo-hydrogen which con- 

 tains all the oxygen, and some gaseous com- 

 pounds of carbon and hydrogen being pro- 

 duced. 



It is evident that during transformations 

 caused by heat, no foreign affinities can be 

 in play, so that the new compounds must 

 result merely from the elements arranging 

 themselves., according to the degree of their 

 mutual affinities, into new combinations 

 which are constant and unchangeable in 

 *he conditions under which they were origi- 

 nally formed, but undergo changes when 

 these conditions become different. If we 

 compare the products of two bodies, similar 

 in composition but different in properties, 

 which are subjected to transformations by 

 two different causes, we find that the man- 

 ner in which the atoms are transposed, is 

 absolutely the same in both. 



In the transformation of wood in marshy 

 soils, by what we call putrefaction, its car- 

 bon is shared between the oxygen and hy- 

 drogen of its own substance, and of the 

 water carburetted hydrogen is consequently 

 evolved, as well as carbonic acid, both of 

 which compounds have an analogous com- 

 position (CH2, CO2.) 



Thus also in that transformation of sugar, 

 which is called fermentation, its elements 

 are divided into two portions ; the one, car- 

 bonic acid, which contains f of the oxygen 

 of sugar ; and the other, alcohol, which con- 

 tains all its hydrogen. 



In the transformation of acetic acid pro- 

 duced by a red heat, carbonic acid, which 

 contains 2-3 of the oxygen of the acetic acid 

 is formed, and acetone, which contains al 

 its hydrogen. 



It is evident from these facts, that the ele- 

 ments of a complex compound are left to 

 their special attractions whenever their equi- 

 librium is disturbed, from whatever cause 

 this disturbance may proceed. It appears 

 also, that the subsequent distribution of the 

 elements, so as to form new combinations 

 always takes place in the same way, with 

 this difference only, that the nature of the 

 products formed is dependent upon the num 

 oer of atoms of the elements which ente 

 into action ; or, in other words, that the pro- 

 ducts differ ad infinitum, according to the 

 composition of the original substance 



N THE TRANSFORMATION OF BODIES COW- 

 TAINING NITROGEN. 



When those substances are examined 



which are most prone to fermentation and 



utrefaction, it is found that they are all, 



without exception, bodies which contain 



itrogen. In many of these compounds, a 



ransposition of their elements occurs spon- 



aneously as soon as they cease to form part 



f a living organism; that is, when they are 



Irawn out of the sphere of attraction in 



which alone they are able to exist. 



There are, indeed, bodies destitute of ni- 

 rogen, which possess a certain degree of 

 liability only when in combination, but 

 which are unknown in an isolated condition, 

 jecause their elements, freed from the power 

 )y which they were held together, arrange 

 hemselves according to their own natural 

 attractions. Hypermanganic, maganic, and 

 lyposulphurous acids, belong to this class 

 of substances, which however are rare. 



The case is very different with azotised 

 )odies. It would appear that there is some 

 Deculiarity in the nature of nitrogen, which 

 *ives its compounds the power to decom- 

 pose spontaneously with so much facility. 

 Mow, nitrogen is known to be the most in- 

 different of all the elements; it evinces no 

 particular attraction to any one of the simple 

 bodies; and this character it preserves in all 

 ts combinations, a character which explains 

 the cause of its easy separation from the 

 matters with which it is united. 



It is only when the quantity of nitrogen 

 exceeds a certain limit, that azotised com- 

 pounds have some degree of permanence, as 

 is the case with melamin, ammelin, &c. 

 Their liability to change is also diminished, 

 when the quantity of nitrogen is very small 

 in proportion to that of the other elements 

 with which it is united, so that their mutual 

 attractions preponderate. 



This easy transposition of atoms is best 

 seen in the fulminating silvers, in fulmi- 

 nating mercury, in the iodide or chloride of 

 nitrogen, and in all fulminating compounds. 

 All other azotised substances acquire the 

 same power of decomposition, when the 

 elements of water are brought into play ; 

 and indeed, the greater part of them are not 

 capable of transformation, while this neces- 

 sary condition to the transposition of their 

 atoms is absent. Even the compounds of ni- 

 trogen, which are most liable to change, 

 such as those which are found in animal 

 bodies, do not enter into a slate of putrefac- 

 faclion when dry. 



The resull of the known transformations 

 of azotised substances proves that the water 

 does not merely act as a medium in which 

 motion is permitted to the elements in the 

 act of transposition, but thai its influence 

 depends on chemical affinity. When the 

 decomposition of such substances is effected 

 with the assistance of water, their nitrogen 

 is invariably liberated in the form of ammo- 

 | nia. This is a fixed rule without any excep* 



