Treatise on human physiology : For the use of students & practitioners of medicine / By Henry C. Chapman. Illustrated with 595 engravings.

Henry Cadwalader Chapman

Date:: 1899

Credit: Treatise on human physiology : For the use of students & practitioners of medicine / By Henry C. Chapman. Illustrated with 595 engravings. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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$Wherever practicable, the historical order will be found to be the best cue to pursue in the study of any science ; indeed, as we pro- ceed, it will be seen that the phenomena of physiology depend upon physical and chemical laws, and that probably, with the advance of knowledge, the whole subject will be treated as a branch of molecu- lar physics—hence the indispensability to the student of physiology of a knowledge of physical and chemical science. Ample illustra- tions of the value of such knowledge 'svill be given when the special functions are considered. The special senses of sight and hearing, for example, depend for their successful study u])on familiarity with optics and acoustics ; the investigation of the circulation is a ques- tion of hydraulics ; that of secretion, of organic chemistry. By referring to the classification just oifered, it will be observed that Botany comes before Zo<')logy ; where practicable, its study should precede that of Zoology, for plants serve to bridge over, to a certain extent, the gap between the mineral and animal worlds, and at diiferent points touch the confines of these two kingdoms. Further, with some exce})tions, plants are destitute of a nervous system, and even if extended investigation should show that their nervous system is more developed than now it is supposed to be, it would exercise a small influence as compared with that of the higher animals. Plants, therefore, oifer a favorable opportunity of examining the processes of nutrition iminfluenced by the nervous system. When we come to examine the circulation, digestion, etc., in man, we shall see that these functions are greatly modified by the nervous system ; hence the advantage of studying nutrition in lower organizations where these disturbing elements are eliminated. Having endeavored to define the object of our study, and to indi- cate its limits and relation to knowledge in general, let us now con- sider the different methods by which human physiology can be investigated—and, first, a great deal can be learned of the functions of the human body by careful reflection on the structure of the same. Haller ^ says : and first the fabric of the human body is to be learned, whose parts are almost infinite. Those who would study physiology separately from anatomy certainly seem to me, can be compared with mathematicians who undertake to express, by calculation, the forces and functions of a certain machine of which they have learned neither disks, wheels, measures, nor material. Truly I am persuaded that we know scarcely anything of physiology unless we have learned it through anatomy. Undoubtedly, the functions of many organs might be inferred from the thorough study of their structure. As a matter of history, the demonstration of the valves in the veins by Fabricius to Harvey was one of the important facts that first suggested to the latter to investigate the flo\y of the blood.$