CHEMICAL SCIENCE. 237 



that Messrs. Malre and Valler have sought to utilize as a combustible 

 in industrial furnaces, and particularly in metallurgic operations. 

 Water, fed in a regulated and intermittent manner into a hot fire, is 

 decomposed into oxygen and hydrogen. The combustion of the latter 

 in presence of the atmospheric air (the oxygen of the water being 

 employed in burning the carbon) produces a considerable heat in addi- 

 tion to that of the principal combustible. There results, then, a con- 

 siderable augmentation of caloric without any addition of combus- 

 tible, and consequently a more rapid fusion of metals and minerals, 

 and an economy of fuel which the authors of the process state varies 

 from forty to fifty per cent. Experiments and calculations have 

 demonstrated that the heat absorbed by the decomposition of water is 

 less than that furnished by the combustion of the gaseous products of 

 the water decomposed. 



CURIOUS OBSERVATIONS ON FERMENTATION. 



The Comptes Rendus has recently published a resume of M. Pas- 

 teur's researches on fermentation, from which we derive the following 

 information : 



M. Pasteur began his investigations by experimenting on the vege- 

 table organism known as the mycoderma vini, or the " mother of wine." 

 Causing this plant to develop in various alcoholic liquids in contact 

 with air, he never obtained acetic acid ; and if he introduced a small 

 portion of that acid, it usually disappeared. When the mycoderma 

 aceli, or vinegar-plant, was grown in alcoholic liquids, acetic acid 

 was always- formed, with the intermediate production of small quan- 

 tities of aldehyd. 1 In both cases the chemical phenomena and the 

 life of the plants were clearly correlative. When the experiments 

 were performed in close vessels, containing besides the liquid a known 

 quantity of air, it was ascertained that the vinegar-plant took oxygen 

 from the air, and therewith converted the alcohol into acetic acid; 

 and that the mycoderm of wine took oxygen from the air, and con- 

 verted the alcohol into water and carbonic acid. It was likewise 

 ascertained that if the alcohol was removed, and the vinegar-plant 

 grown in an acetic liquid, the acid was transformed into water and 

 carbonic acid. With the mycoderm of wine the effect was the same, 

 especially if there was a little alcohol in the liquid. From these facts 

 M. Pasteur concludes that the wine and vinegar-plants behave in the 

 same manner, and that there are circumstances in which their action 

 is exalted ; that is to say, that the plant, instead of taking from the 

 air two or four molecules of oxygen to combine with one molecule of 

 alcohol, and thus produce aldehyd or acetic acid, takes eight or twelve 

 molecules of oxygen, and by their aid completely transforms the alco- 

 hol and the acetic acid into water and carbonic acid. The vinegar- 

 plant does not produce acetification when it is submerged. This Avas 

 ascertained by noting the degree of acidity of a liquid in which a 

 growing plant floated. The plant was made to sink by glass rods, 

 and the acetification was arrested. Following his investigations, M. 



1 "The alcohols may all be regarded as compound oxides of hydrogen, and of a 

 peculiar hydrocarbon. . . . The alcohols, by imperfect oxidation, furnish, 

 aldehydsi and these bodies, by the further absorption of oxygen, yield acids." 



