48 FISH CULTURAL ASSOCIATION. 
something of the ways in which the facts, as far as we know 
them, have been found out; of the thousands of chemical 
analyses of vegetable and animal substances that constitute our 
foods and the tissues and fluids of our bodies; of the years and 
years of labor of many men that have been devoted to the ex- 
perimental study of the ways in which the food is used, the body 
built up, and its tissues consumed again; of the wonderfully 
complicated and yet beautifully simple instruments and oper- 
ations by whose aid the utmost ingenuity of science has sought 
to discover the subtle processes by which the transformations go 
on in the body and flesh and fat are stored and heat and force 
produced. Suffice it to say, that the research of the past fifteen 
years, especially, has taught us much of the fundamental prin- 
ciples of nutrition, though we are still in the dark as to many of 
the details, as the interrogation point after the last word in the 
schedule implies. So let us return to our subject—the nutrients 
of our foods and their functions in nutrition. 
Leaving out of account the water and mineral substances 
which, though essential to nutrition, are not to our present pur- 
albumi- 
pose, we have three classes of nutrients in our 
noids, carbohydrates, and fats. 
ALBUMINOIDS, PROTOPLASM. 
A little short of a dozen years ageo many earnest-minded 
people on both sides of the Atlantic were startled by an address 
from Professor Huxley,,on “A Physical: Basis: of Life gale 
“formal basis of life,” this soulless. substance in which vital 
phenomena were centred, while vitality, as a force, was exclu- 
ded, was protaplasm, a material containing “the four elements, 
carbon, hydrogen, oxygen, and nitrogen, in very complex union. 
To this complex combination the name protein has 
Been applied, and if we use this term with such caution as may 
properly arise out of our comparative ignorance of the things 
for which it stands, it may be truly said that all protoplasm is 
protinaceous, or, as the white or albumen of an egg is one of 
the commonest examples of a nearly pure protein matter, we 
may say that all living matter is more or less albuminoid.” 
