L74 FISH-CULTURAL ASSOCIATION. 
cows, sheep, goats and swine—with dogs, rabbits, birds and the 
like, anda large number also with human beings of both sexes and 
different ages. Inthe philosophical planning of the researches, 
in the ingenuity manifested in devising apparatus, in accuracy, 
thoroughness, patience, and long. continuance in the work, as 
well as in the distinguished genius of many of the workers, 
chemico-physiological science has assumed the highest rank 
among the sciences of our time; with the rest it has brought us 
where we can estimate the nutritive values of foods from their 
chemical composition, with so near an approach to accuracy that 
in Germany, where the best research is done, tables, giving in 
figures, the composition and nutritive valuations of foods, have 
been prepared by eminent chemists and physiologists, and are 
coming into general use among the people. 
We eat meat and fish, potatoes and bread, to build up our 
bodies, to repair their wastes, and to supply them with fuel for 
the production of heat and muscular force. 
Of the meat my butcher sends me, the fish I find in the mar- 
ket, the bread and the other food upon my table, only a part 
serves to fulfill these purposes. The bone of our roast beef we 
do not use for food at all, and that of shad is worse than useiess 
because of the bother it makes us to get rid of it ; it is only the 
edible portion that is of actual value to us as food, the rest be- 
ing merely refuse. And when we come to consider the edible 
portion, the meat freed from bone and gristle, the flesh of the 
fish, or the flour as it is baked in bread, we find that these con- 
sist largely of water. And although water is indispensable, 
that in the meat or the potatoes on my table is of no more valuable 
for the support of my body, than the same amount in milk or in 
the glass of water by my plate. 
Leaving out of account, then, the refuse and the water, we 
bave remaining the nutritive material of our food. This con- 
sists of different materials which we may call nutrients. We 
may divide them into four classes: protein, fats, carbo-hydrates 
and mineral matter, or ash. Let me speak briefly of some of 
the characteristics of these classes of nutrients. 
Protein.—The terms protein, proteids, and albuminoids, are 
applied somewhat indiscriminately, in ordinary usage, to several 
