March 1, 1865.] THE TECHNOLOGIST. 



ON CHEMISTRY APPLIED TO THE ARTS. 353 



atmospheric air of the sporules or eggs of mycoderma and vibrios, or 

 organized ferments, which give rise to the various chemical phenomena 

 • and changes of organic matters into products which characterise fer- 

 mentation and putrefaction. The same results are obtained when fresh 

 urine is substituted lor blood, an important fact, proving that the 

 germs of fermentation do not exist in the fluids themselves, and that 

 fermentation does not proceed fom any molecular or chemical change in 

 the composition or nature of the organic substances contained in blood 

 and urine, but that the ferment from which these phenomena proceed 

 is to be sought for in the atmosphere. I shall substantiate this view by 

 several other interesting observations made by M. Pasteur. 



If some asbestos is heated to a red heat and plunged into a liquor 

 susceptible of putrefaction, such as a saccharine liquor, no fermenta- 

 tion ensues, but if atmospheric air is passed through asbestos at 

 natural temperature, and the latter then immersed in a similar solution 

 of sugar, active fermentation soon takes place, proving that the atmo- 

 spheric air has left on the surface of the asbestos sporules of the 

 Mycoderma vini, which, being introduced with the asbestos into the 

 saccharine fluid, orginated the well-known alcoholic fermentation. 

 Another beautiful series of experiments by M. Pasteur is the following : 

 —He introduced into sixty small balloons a small quantity of a highly 

 putrescible fluid, and after boiling the fluid in order to drive out the air 

 remaining in the balloons by the formation of steam, he closed the small 

 apertures so that on cooling the steam condensed and a vacuum was 

 produced. He then proceeded to open twenty of these balloons at the 

 foot of one of the hills of the Cote. d'Or, twenty others at the summit 

 of the same (about 2,000 feet high), and the remaining twenty at a point 

 near Chamounix, and the following results were observed : Of the first 

 twenty balloons the contents of fifteen entered into putrefaction within a 

 few days ; of the second twenty only six, and of the third twenty only 

 two gave signs of fermentation. These results, as well as some others 

 published by M. Pasteur, prove that the sporules or germs of putrefac- 

 tion and fermentation exist in all parts of the atmosphere, but more 

 abundantly in the lower strata, which are necessarily in contact with 

 great quantities of organic matter in a state of decay, and that these 

 sporules become scarce in the upper regions of the atmosphere, which 

 are further removed from the source of pollution. Further, he has 

 proved, as I stated in my last lecture, when speaking of the preservation 

 of milk, that fluids extremely liable to fermentation or putrefaction may 

 be prevented from entering into those conditions by heating them to 

 250° or 260°, a temperature at which the sporules cannot resist decom- 

 position in the presence of water. M. Pasteur has advanced a step fur- 

 ther in this interesting inquiry, for he has demonstrated that there are 

 two distinct phases in putrefaction. In the first there are the vibrios 

 produced in the bulk of the fluid containing animal matters in solution, 

 and that these microscopic animals resolve the organic substances into 



