March 1, 1865.J THE TECHNOLOGIST. 



ON CHEMISTRY APPLIED TO THE ARTS. 345 



Preservation of Meat and Animal Substances. — A low temperature is 

 most favourable to the preservation of flesh and other animal substances, 

 and under that condition it will not enter into putrefaction, the best 

 proof of which is that elephants in a perfect state of preservation have 

 been found in Siberia buried in ice, where they have doubtless existed 

 for many thousands of years. It is also well known that the inhabitants 

 of polar regions preserve their meat fresh by burying it in snow, and I 

 mentioned an instance in one of my previous lectures, viz., the pre- 

 servation and bleaching of sturgeon's bladders on the banks of the Volga. 

 A high state of desiccation or dryness also contributes powerfully to 

 -the prevention of decay. Thus, in Buenos Ayres and Monte Video 

 meat is cut into thin slices, covered with maize flour, dried in the sun, 

 and it is consumed largely, under the name of " tasago " or "charqui," by 

 the inhabitants of the interior, and also by the black population in Brazil 

 and the West Indies. Further, dried meat reduced to powder is used 

 by travellers in Tartary and adjacent countries, and I may add that of 

 late years meat biscuits have been extensively consumed by the emi- 

 grants having to travel from the United States to California and the 

 West Coast. generally. It is stated that six ounces per diem of this meat 

 biscuit will maintain a man in good health throughout the journey. A 

 remarkable instance of the preservation of animal matter by extreme 

 desiccation is related by Dr. Wefer, who states that in 1787, during a 

 journey in Peru, he found on the borders of the sea many hundreds of 

 corpses slightly buried in the sand which, though they had evidently 

 remained there for two or three centuries, were perfectly dry and free 

 from putrefaction. Although it is not within the scope of these lectures 

 to describe the preservation of vegetable matters, still I cannot refrain 

 from mentioning the interesting method adopted by MM. Masson and 

 Gannal, by which, as you are doubtless aware, vegetables are preserved 

 in the most perfect manner. Their process is most simple, as it consists 

 in submitting the vegetables for a few minutes to the action of high- 

 pressure steam (70 lbs. to the square inch), then drying them by air 

 heated to 100°, when, after compression by hydraulic pressure, they are 

 made into tablets for sale, and when required for use it is only necessary 

 to place the tablets for five hours in cold water, when the vegetable 

 substances swell out to their former size and appearance, and are ready 

 for cooking. As the presence of oxygen or air is an essential condition 

 of putrefaction, the consequence is, that many methods have been 

 invented to exclude that agent, or rather, as I shall show at the end of 

 this lecture, the sporules or germs of cryptogamic plants or animals, 

 which are the true ferments or microscopic source of fermentation aud 

 putrefaction. Permit me to describe concisely some of the methods 

 proposed ; and I believe that one of the best processes for excluding air 

 was that invented by Appert, in 1804. It consists in introducing the 

 meat or other animal substance with some water into vessels which are 

 nearly closed, these are then placed in a large boiler with salt (which 



