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beef, but with other parts of animals still more prone to decomposition, 

 as brain, blood, lungs, hide, &c. 



Before entering fully into these experiments, it was thought desii'able 

 that I should state my opinion in writing, and shew the ground on 

 which a hope might be founded of ultimate success. This statement 

 was produced and read, on the lOtli of March, 1853. It contained 

 the following passages : — 



Beef is liable to change from two causes, which are essentially 

 distinct from each other : — 



1st. Combination with oxygen, supplied by the atmosphere : in pre- 

 sence of watery vapour, the elements of the substance form gaseous 

 products, which pass off. Chemists call this process eremacausis. 



2nd. A change in the internal arrangement of the atoms of the 

 substance, in some cases without the agency of atmospheric air. This 

 change proceeds most rapidly with a scanty supply of air, and a slightly 

 elevated temperature. The albumen of the meat decomposes, and acts 

 as a ferment, which soon extends through the whole mass. This pro- 

 cess is properly called putrefaction. 



It is possible to prevent both oxidation (eremacausis) and putrefac- 

 tion, by various means ; but the condition, that the meat shall be in all 

 respects like fresh meat, in colour, consistence, and taste, and be fit for 

 human food, surrounds the problem with difficulties. 



If the meat were placed, as you suggest, in an air-tight vessel, con- 

 nected with an aii'-pump, the air could not be completely exhausted by 

 working the pump, however long ; and, as putrefaction is hastened 

 by diminution of pressure, an imperfect vacuum would be worse than 

 useless. But when the exhaustion is as complete as the power of the 

 pump will allow, if a gas were introduced which would combine with 

 the oxygen remaining in the pores of the meat, as well as that in the 

 containing vessel, the whole of the oxygen could be withdrawn. 

 Binoxide of nitrogen would effect this object perfectly. The vacuum 

 thus left might be filled up with some non-oxidizing gas, such as car- 

 bonic acid, carbonic oxide, nitrogen, or hydrogen; but as I am entirely 

 ignorant of the effects which these gases would be likely to produce 

 on the colour, consistence, and taste of tho meat, I know of no way of 

 answering your question satisfactorily, without entering on a long and 

 tedious series of e.xperiments. 



The following are a few of tlic experiments which I made : — 



First Series. 

 Experiment 1 . — Placed six pounds of fresh beef in a box, over a 

 laver of chloride of lime, the beef resting on a board perforated with 



