108 
The Supphj of Milk to Labourers. 
Looking at mj subject from this point of view, it is essential 
to know what constitutes a good diet, and what is the com- 
parative position of milk among the different kinds of food. 
" Practically," continues Dr. Pavy, after further remarks on the 
theory of nutrition and the respective values of the two groups 
of alimentary substances, nitrogenous and non-nitrogenous, ' it 
is found that hard work is best performed under a liberal 
supply of nitrogen-containing food. The reason probably is 
that it leads to a better nourished condition of the muscles and 
of the body generally. Under the use of animal food which 
is characterised by its richness in nitrogenous matter, the 
muscles, it is affirmed, are observed to be firmer and richer in 
solid constituents than under subsistence upon food of a vege- 
table nature." I must refer the reader to Dr. Pavy's elaborate 
work for further information on the value of different kinds of 
food, and to Dr. Parkes's popular manual on the ' Personal 
Care of Health,' for some excellent practical suggestions on the 
same subject. The evidence collected by Dr. Pavy all tends 
to establish that " practically," to quote his expression, we may 
take the amount of the nitrogenous elements in food as the test of 
its value to labouring men, with somededuction in the case of milk, 
compared with some other articles, on account of its larger per- 
centage of water and its poverty in the carbonaceous elements. 
The analyses of different kinds of food will, at least, enable 
us to draw a few broad conclusions as to their respective value. 
A pound of uncooked beef, for example, contains four times 
as much nitrogenous matter as a pint of milk, and it costs in 
London about four times as much — the price of beef being 
IQd. per lb. and of milk 2^d. per pint. The necessities of the 
labourer's pocket, however, direct him to the purchase of less 
costly food. He obtains in a pound of cheese seven times as 
much nitrogenous matter and nearly eight times as much fatty 
matter as in a pound, or pint, of milk. In bread he obtains 
nearly twice as much nitrogenous matter and a large supply of 
carbonaceous substances. In dried bacon and fat pork he obtains 
twice as much nitrogenous matter and a very large supply of fat. 
In the works of Dr. Pavy, Dr. Parkes, and Dr. Playfair a 
number of dietaries suited to men under various circumstances, 
whether engaged in laborious or light work, are given. A 
typical dietary for a labouring man is 2 lbs. of bread and f lb. 
of uncooked lean beef daily, supplying — 
oz. 
Nitrogenous matter 4 "908 
Fat 0-944 
Carbo-hydrates lG-o20 
Mineral matter 1 • 348 
23-520 
