Heat and Life: The Development of the Theory of Animal Heat

This work originated in an effort to find out what elements wento into concept formation in the biological sciences and what the relation of this process is to the knowledge and techniques of the physical sciences. Mr. Mendelsohn investigates in detail the history of a single biological theory, that of animal heat, and traces its changes through time and the sources of these changes. In one form or another, the heat of the warm-blooded animal was recognized and explained from the earliest times, and the necessity of reconciling biological and physical heat was always present. The biologist needs to know whether a biological phenomenon can usefully be reduced to a physical or mechanical analogue or whether one must seek strictly biological theories to explain biological phenomena. The author carries the story from the speculations of the ancient Greeks, through Harvey's ideas related to the circulationl of the blood, to the explanation based on respiraion and combustion at the end of the eighteenth century. The architects of the new theory of animal heat, tying their work closely to the latest developments in chemistry and physics, repudiated the idea that special biological laws governed the behavior of living systems. The problem of animal heat and the new concepts and techniques developed in the late eighteenth century for constructing a theory to explain it can be taken as marking the beginning of scientific biology. Everett Mendelsohn teaches the history of science at Harvard University.