as a Food for Pigs. 
437 
it appears very desirable to ascertain, by a more prolonged 
series of experiments, whether this new food can really be em- 
ployed economically for the purpose of increasing the assimi- 
lation and value of ordinary feeding stuffs upon which pigs are 
usually kept. Probably it will be found that the mutton extract 
is not a food which, like l)arley-meal or peas, supplies to the 
animal body in a direct manner the necessary amount of albu- 
minous compounds, starch, and other food-constituents required 
for the formation of muscle and fat, and supporting respiration, 
but that it exerts a useful physiological function in the elabo- 
ration of ordinary food. It has been pointed out that Concen- 
trated Mutton-soup contains from 18 to 20 per cent, of real 
meat extract, soluble in alcohol. From the constituents of this 
meat extract chemists have already isolated kreatin, sarkin, and 
carnin, three well-defined organic compounds, belonging to the 
group of organic bases or alkaloids. Another organic consti- 
tuent of meat extract is a modification of lactic acid, and there 
are, no doubt, other organic compounds in the juice of meat, 
which as yet have not been isolated. Besides the basic and 
acid organic compounds, extract of meat contains a large propor- 
tion of phosphate of potash and other saline matters, and thus 
possesses a highly complex composition. Although but little 
is known with regard to the precise physiological functions of 
the various constituents of meat extract, our present experience 
tends to indicate that meat extract materially assists in the assi- 
milation of food, and in consequence possesses a certain physio- 
logical and possibly economic value. 
11, Salisbury Square, Fleet Street, 28th July, 1873. 
XVIII. — On Foot-and-Mouth Complaint of Cattle and other 
Animals ; with Remarks on the general characters of the disease 
and the causes tohich led to its recent extensive prevalence in this 
kingdom. By G. T. Beown, Chief Inspector in the Vete- 
rinary Department of the Privy Council and Professor of 
Physiology and Therapeutics in the Royal Veterinary College. 
History of Foot-and-Mouth Disease. 
Epizootic aphtha, eczema, or foot-and-mouth distemper, is well 
known in this kingdom ; its origin, like that of infectious and con- 
tagious disorders in general, is wrapped in mystery. Obviously 
it had a beginning, and the first animal attacked could not have 
taken the disease from a previously affected animal ; but of the 
2 G 2 
