476 ARTIFICIAL MAitBLE AND CEMENT, MADE WITH MAGNESIA. 
cadaverous, and it often has the odour of medicine. This is best observed by cutting it 
and smelling the knife, or by pouring a little warm water upon it. Good meat will bear 
cooking without shrinking, and without losing very much in weight; but bad meat 
shrhels up, and it often boils to pieces. All these effects are due to the presence of a 
large proportion of serum in the meat, and to the relatively large amount of intercellular 
or gelatinous tissue; for the fat and true muscular substance are to a greater or less 
extent deficient. If, therefore, 100 grains of the lean or muscular part of good meat are 
cut up and dried at a temperature of boiling salt and water (224° Fahrenheit) thev lose 
only from 69 to 74 grains of their weight; but if diseased meat is thus treated, it'loses 
from 75 to 80 per cent, of its weight. I find that the average loss of weight with sound 
and good beef is.72\3 per cent., and of mutton 7F5 per cent., whereas the average loss 
of diseased beef is 76T per cent., and of diseased mutton 78'2 per cent. Even if it be 
dried at a higher temperature, as at 266° Fahrenheit, when all the moisture is expelled 
and when good meat loses from 74 to 80 per cent, of its weight, the proportion of loss 
m bad meat is equally great. Other characters, of a more refined nature, will also serve 
to distinguish good from bad meat. The juice or serosity of sound flesh is slightly acid, 
and it contains an excess of potash salts, chiefly the phosphate ; whereas diseased meat, 
irom being infiltrated with the serum of blood, is often alkaline, and the salts of soda, 
especially chloride and phosphate, abound in it. Lastly, when good meat is examined 
undei the microscope, the fibre is clean and well-defined, and free from infusorial crea¬ 
tures ; but that of diseased meat is sodden, as if it had been soaked in water, and the 
transverse markings are indistinct and far apart; besides which, there are often minute 
organisms like infusorial bodies. These are very perceptible in the flesh of animals 
^tedwflh the cattle plague, and Dr. Beale has described them as entozoa-like objects. 
1 ey differ altogether from the parasites which constitute the trichina disease, and the 
measles ot pork. How far the use of diseased meat affects the human constitution is 
unknown.. In those cases where certain parasitic diseases exist in animals, there is no 
aoubt of its injurious nature ; for the tape-worm, the trichina, and certain hydatid or 
encysted growths are unquestionably produced by it. Experience also points to the fact 
that carbuncle and common boils are in some degree referable to the use of the flesh of 
animals affected with pleuro-pneumonia ; and occasionally we witness the most serious 
diarrhoea and prostration of the vital powers after eating diseased meat. It is, therefore, 
safest to forbid its use ; and it is at all times best to guard against the possibilitv of 
? n J ui y having meat well cooked. It should be so cooked that the very centre of the 
joint should be exposed for some time to the temperature of 212° Fahrenheit. The 
instructions of Liebig in this particular are hardly safe ; for although a temperature 
below that of boiling water may coagulate albumen and develope the flavours of cooked 
meat, it may not ensure the destruction of dangerous parasites. It is therefore better 
to have the meat a little overcooked than otherwise .”—Chemical News. 
NEW ARTIFICIAL MARBLE AND CEMENT, MADE WITH MAGNESIA. 
M. Sainte Claire-Deville has lately made an interesting discovery and a series of ex¬ 
periments, which may lead to important practical results. The investigation origi¬ 
nated in an observation of the effect produced by water on a sample of magnesia 
obtained by the calcination of chloride of magnesium. This anhydrous magnesia, 
m compact fragments, says M. Deville, was left for several months in a current of 
water running from a tap in his laboratory at the Ecole Normale, and finally assumed a 
wv! ar k a ^ consistency, having the density and more than the hardness of marble. 
When divided into rather thin pieces, it became translucent, like alabaster, and the in¬ 
terior of the mass was crystalline. At the end of six years, during which time it was 
exposed to the air, no change took place in its condition. When analysed, it was found 
to contain Water, 27’7 parts; carbonic acid, 8'3; alumina and iron, 1*3; magnesia, 
5/ 1 ; and sand, 5‘6. M. Deville pulverized some of this substance and mixed it with 
■water, till he produced a semi-plastic mass, and he then left it for several weeks in a 
tube containing distilled water deprived of gas by boiling, and enclosed in a glass tube 
hermetically sealed. I he magnesia combined slowly with the water, and became as- 
compact and as hard as the first-mentioned specimens. The desiccation caused by ex- 
