480 
ANALYSIS OF CONTINENTAL JOURNALS. 
They contribute in the formation and maintaining of the 
viscera, glands, muscles, bones, &c. They also repair the loss 
sustained by the liver, the epidermis, epithelium, mucus, 
caseine, &c. Justly called plastics , they represent in some 
way the metal by which a machine is repaired. 
The fatty and saccharine matters, also called neuter , are ex- 
clusively composed of carbon, oxygen, and hydrogen; che- 
mists and physiologists group them under the name of 
respiratory elements , tliermogen , or dynamogen , because, by the 
combination of their carbon and hydrogen with the oxygen, 
they produce the animal heat. The composition of the saccha- 
rines is nearly as follows : 
Carbon . . 42 { Water . .58 
All fatty matters [corps gros) are formed of a great quantity of 
carbon and hydrogen ; some even contain no oxygen; accord- 
ing to M. Boussingault, oil and fat, whatever their origin, 
contain 
Carbon . 79 | Hydrogen . 11 | Oxygen . 10 
As aliment the animals cannot take them without incon- 
venience, their composition being that of all the fatty matter 
contained in the food ; admitting that 10 per cent, of oxygen 
combine with T25 of hydrogen, and form water, 9*7-5 of the 
latter would be set free, so that the thermogen value of the 
fatty matter may be represented by 79 of carbon and 9*75 of 
hydrogen. We will not follow the author in the minute cal- 
culation of the quantity of carbon and of hydrogen which is 
necessary to produce by combustion one inch of caloric. 
He resumes, by stating, that 
100 parts of saccharoids contain 42*0 of carbon. 
100 „ fatty matter „ 120*5 ,, 
100 „ albuminoid „ 16 0 of nitrogen. 
Consequently, 100 parts of nitrogen represent 625 of 
albuminoids. 
In 1856 (the author states), when the third edition of his 
general hygiene was in print, he was led to make researches 
into the effects produced by the economical rations so much 
tried at that time ; he found that the nitrogenous principles 
had not the importance in the food of working horses that 
had so long been attributed to them, and that it was neces- 
sary to furnish to these animals aliments rich in the hydro- 
carbonous elements; he observed, that all rations containing 
in relation to the plastic principle a less amount of fatty matter 
than is contained in meadow hay and oats, did not keep horses 
in good condition which have to perform work attended with 
