PUTREFACTION 671 



4. Abstraction of oxygen gas. As the putrefactive decomposition of a body first 

 commences with the absorption of oxygen from the atmosphere, so it may be 

 retarded by the exclusion of this gas. It is not, however, enough to remove the 

 aerial oxygen from the surface of the body, but we must expel all the oxygen that 

 may be diffused among the vessels and other solids, as this portion suffices in general 

 to excite putrefaction, if other circumstances be favourable. The expulsion is most 

 readily accomplished by a boiling or lower heat, which, by expanding the air, 

 evolves it in a great measure. Milk, soup, solution of gelatine, &c., may be kept 

 long in a fresh state, if they be subjected in an air-tight vessel every other day to a 

 boiling heat. Oxygenation may be prevented in several ways : by burning sulphur 

 or phosphorus in the air of the meat receiver; by filling this with compressed 

 carbonic acid ; or with oils, fats, syrups, &c., and then sealing it hermetically. 

 Charcoal-powder recently calcined is efficacious in preserving meat, as it not only 

 excludes air from the bodies surrounded by it, but intercepts the oxygen by con- 

 densing it, and causing it to combine with putrefying substances. When butchers' 

 meat is enclosed in a vessel filled with sulplnirous acid, it absorbs the gas, and 

 remains for a considerable time proof against corruption. The same result is obtained 

 if the vessel be filled with ammoniacal gas. At the end of 76 days such meat has 

 still a fresh look, and may be safely dried in the atmosphere, 



Peculiar Antiseptic Processes. Upon the preceding principles and experiments 

 depend the several processes employed for protecting substances from putrescence and 

 corruption. Here we must distinguish between those bodies which may be preserved 

 by any media suitable to the purpose, as anatomical preparations or objects of natural 

 history, and those bodies which, being intended for food, can be cured only by whole- 

 some and agreeable means. 



Preservation of specimens of animals, <-c. Many methods have been planned to 

 preserve animals : all of them dependent on substances mentioned under DIS- 

 INFECTANTS. Charles Waterton used corrosive sublimate dissolved in alcohol. The 

 skin of the animal being separated, is dipped into the solution and dried. The inside 

 of the animal is always removed, the bones scraped clean and dipped, the feathers or 

 hairs touched by the solution, or the whole immersed in it. Sometimes alcohol of 

 60 to 70 per cent, is used, or alcohol of 30 per cent, with creasote dissolved in it. 

 Sulphurous acid will not suit when there are colours, but sulphites of the alkalis 

 have been injected into the veins and arteries with good result ; as also sulphurous 

 acid and creasote. Peron preserved fishes for specimens on shipboard by floating 

 them in an alcoholic liquor by corks, thus preventing them from being pressed. He 

 first washed them in sea-water, vinegar, and camphor spirits : he corked the vessels 

 with tallowed corks. Dufresne wrapped each in a cloth with tow between the speci- 

 mens, and all in alcoholic liquids. Louis Vernet used arsenic, 1 Ib. in 40 gallons of 

 water. Sulphate of zinc was proposed for embalming by Comte de Fontainemoreau, 

 sometimes adding alcohol. Wood is preserved by Kyan's process, corrosive sublimate 

 being used ; also by Bethel's process, the use of heavy oil of tar ; and manures are 

 preserved by carbolates by MacDougall. Injection of the arteries and veins by 

 chloride of zinc, chloride of arsenic, and chloride of aluminium, sulphate of zinc, and 

 sulphates, corrosive sublimate, &c., have all been tried, and are more or less satis- 

 factory. Peppers and spices of all kinds have been used in stuffing and embalming, 

 and may all be made to act when care is employed and abundance used. Girolamo 

 Segato dried bodies so hard that he made a table of 214 pieces of human flesh from 

 different parts of the body. He is said also to have made members preserve their 

 elasticity for an indefinite time. Some remarkable specimens of this kind are said to 

 exist, and have received the honour of sanctity. Waterton made skins preserve their 

 flexibility for some days by the use of corrosive sublimate and slow drying. Dr. Ure 

 says, ' for preserving animal bodies in an embalmed form, mummy-like, a solution of 

 chloride of mercury and wood-vinegar is most efficacious. As there is danger in 

 manipulating with that mercurial salt, and as in the present state of our knowledge of 

 creasote, we have it in our power to make a suitable strong solution of this substance 

 in vinegar or spirit of wine, I am led to suppose that it will become the basis of most 

 antiseptic preparations for the future.' 



CUBING OF PBOVISIONS. 



Flesh, $c. The ordinary means employed for preserving butchers' meat are, drying, 

 smoking, salting, and pickling or souring. 



Drying. The best mode of operating is as follows : The flesh must be cut into 

 slices from 2 to 6 ounces in weight, immersed in boiling water for five or six minutes, 

 and then laid on open trellis-work in a drying-stove, at a temperature kept steadily about 

 122 F., with a constant stream of warm dry air. That the boiling water may not 



