THE TECHNOLOGIST. [March 1, 1865. 



354 ON CHEMISTRY APPLIED TO THE ARTS. 



more simple compounds ; in the second phase, there are produced on 

 the surface of the fluid cryptogams, which he calls niycoderms, and 

 which ahsorb oxygen from the air, and oxidise the products developed 

 hy the vibrios. In the case of the fermentation of vegetable substances, 

 such as saccharine matters, there are mycoderms (Mycoderma vini), 

 which resolve them into, say alchol and carbonic acid, while other 

 mycoderms {Mycoderma aceti) are produced, and grow on the surface of 

 the fluid, oxidising alcohol into water and acetic acid. He therefore 

 concludes that the animal vibrios and vegetable mycoderms exist 

 abundantly in nature, and that they must be and are the most active 

 causes of the destruction of vegetable and animal substances which have 

 fulfilled their vital function on the earth, reducing them into water, 

 carbonic acid, ammonia, sulphuretted hydrogen, &c, which, in their turn, 

 become the food of a succeeding generation of plants and animals, 

 We may therefore truly say that death is life in the constantly reviving 

 world. 



M. Pasteur has observed another most curious fact connected with 

 these microscopic beings — (I say microscopic, because it requires a most 

 powerful instrument and high powers to distinguish them, and to ascer- 

 tain that vibrios possess a vibratory motion while mycoderms are 

 stationary) ; this is, that vibrios are the only animals which can live in 

 pure carbonic acid, and which are killed by oxygen even diluted with 

 another gas. Oxygen is essential to the life of mycoderms, and some of 

 them can also exist in carbonic acid. Lastly, M. Pasteur has noticed 

 that if a very small amount of yeast is added to a saccharine fluid, the 

 yeast will not materially increase in quantity, because the new genera- 

 tion which is produced lives on the remains of its parent ; but if phos- 

 phate of ammonia or of lime and some sal ammoniac is added with the 

 yeast, the latter will rapidly increase and occupy several times its origi- 

 nal bulk. It is curious to observe that these microscopic cryptogams 

 require the same kind ofjfood as man. Thus, they require nitrogenated 

 food — so do we. They require mineral food, as phosphates — so do we. 

 They require respiratory food — so do we. They produce carbonic acid 

 as part of their vital functions — so do we. I cannot do better than con- 

 clude this part of my subject by giving the following table descriptive 

 of the various ferments observed by M. Pasteur : — 



Fermentation. 



) i Alcohol. 



Mycoderma f Resolves ) Carbonic acid. 



vini. I sugar. S Succinic acid. 



) ( Gkycerine. 



Mycoderma \ Oxidises t Acetic, 



aceti. J alcohol. \ Water. 



Putrefaction. 



Infusorial Ferments. 



Vibrios resolve animal substances. 



Bacterea oxidises organic matters of an animal origin. 



