The author has aimed to prepare a text-book on human physiology for use in higher schools. The design of the book is to furnish a practical manual of the more important facts and principles of physiology and hygiene, which will be adapted to the needs of students in high schools, normal schools, and academies.
roportion to form water. Thus we have animal starch, or glycogen, stored up in the liver. Sugar, as grape sugar, is also found in the liver. The body of an average man contains about 10 per cent of Fats. These are formed of carbon, hydrogen, and oxygen, in which the latter two are not in the proportion to form water. The fat of the body consists of a mixture which is liquid at the ordinary temperature.
Now it must not for one moment be supposed that the various chemical elements, as the proteids, the salts, the fats, etc., exist in the body in a condition to be easily separated one from another. Thus a piece of muscle contains all the various organic compounds just mentioned, but they are combined, and in different cases the amount will vary. Again, fat may exist in the muscles even though it is not visible to the naked eye, and a microscope is required to show the minute fat cells.
10. Protoplasm. The ultimate elements of which the body is composed consist of "masses of living matter," microscopic in s