502 M. Reiset on the Pfuenomena of Putrefaction. 



by the ammonia of the atmosphere. He now goes furthei", and 

 shows that this is absorbed as gaseous nitrogen. 



These experiments of Ville confirm the results arrived at by 

 Reiset* some time before, on the phsenomena of putrefaction. 

 Reiset's experiments were made with the apparatus used by 

 himself and Reguault in their experiments on the i-espiration of 

 animals. This apparatus consists essentially of a large glass 

 bell-jai', in which are placed the substances experimented upon, 

 of an arrangement for absox'bing carbonic acid, and an arrange- 

 ment for supplying oxygen. In proportion as the carbonic acid 

 is absorbed, a quantity of oxygen exactly equal to it passes in. 

 It will be seen, that if in the decomposition of any nitrogenous 

 organic substance oxygen alone is absorbed, and carbonic acid 

 alone produced, the air in the bell-jar at the conclusion of the 

 experiment will have the composition of normal atmospheric air. 

 If, on the contrary, nitrogen has been produced, the relation 

 between the nitrogen and oxygen will be different from that of 

 common air, and a eudiometric analysis will show how much 

 nitrogen has been produced. By means of the apparatus, the 

 temperature and pressure can be so regulated, that at the com- 

 mencement and termination of the experiment these conditions 

 are the same. 



Reiset's experiments were made with manures of various 

 kinds, and with flesh. His results are as follow : — Organic 

 substances in decomposing absorb a large quantity of oxygen 

 and produce carbonic acid, and the relation between these can 

 be accurately determined. The formation of manure and the 

 putrefaction of flesh are always accompanied by the production 

 of a considerable quantity of free gaseous nitrogen. In a 

 medium containing a sufiicient proportion of c cygen no marsh- 

 gas is formed, but the decomposition of a manure partly plunged 

 under water, gives rise to an abundant disengagement of marsh- 

 gas and of nitrogen, and the air in the bell-jar in this experi- 

 ment contains scarcely any oxygen. In all these experiments 

 care was taken to add to the manures a suflacient quantity of 

 earthy carbonates to facilitate the formation of nitrates. 



In a second series Reiset intends pursuing the study of putre- 

 faction, and of the formation of manure out of contact with the 

 air, either under a layer of water, or in a mass of earth. 



Saussure found that organized substances, when moistened 

 and exposed to the air, are gradually oxidized and converted into 

 water and carbonic acid. CorenM'inderf has taken up this sub- 

 ject, and has arranged an apparatus by means of which the quan- 



* Comptes Rendus, January 14, 1856. 



t Annates de Chimie et de Physique, October 1856, 



