FIXED STANDARDS OF PHYSIOLOGY. 13 



the very outset of our science, we must dismiss the vulgar error that the 

 physical conditions of existence vary in different tribes, and that man is 

 not to be compared with lower forms. We must steadily keep in view 

 the interconnection of all, a doctrine which is the guiding light of modern 

 physiology, and which authorizes us to appeal to the structure and func- 

 tions of one animal for an explanation of the structure and functions of 

 another. The more steadily we keep before us this philosophical con- 

 ception of the interconnection of all organic forms, the clearer will be our 

 physiological views. There has never been created such a thing as an 

 isolated living being. 



From the manner in which these general considerations of the mechan- 

 ical and chemical equilibrium of the system of man have been Necessity and 

 introduced, it will doubtless be seen that it is the first busi- p^gioiogkfi 

 ness of the physiologist to disentangle the variable results standards. 

 which that system presents, as far as may be possible, and offer them un- 

 der a standard estimate ; that at the basis of this science there should 

 be a table setting forth with the utmost exactness all the quantities con- 

 cerned in such a standard type. Thus, assuming the weight of an adult 

 man at 140 pounds, as we have done, it should show the diurnal consump- 

 tion of combustible matter or food, of water, of air the diurnal loss by 

 evaporation, by secretion, by respiration. In contrast with this it should 

 also give the nocturnal. It should also represent the quantity of bile, 

 of saliva, of pancreatic juice ; the weight of each one of the various salts 

 and organic bodies they contain, the diurnal and nocturnal production of 

 heat, &c. 



For the purpose of the practice of medicine, a standard of 140 pounds 

 will perhaps be found most convenient, but in a scientific point of view, 

 and especially for comparative physiology, a standard of 1000 parts is 

 best assumed. I now present an attempt at the construction of such ta- 

 bles, it being perhaps scarcely necessary to apologize for their extreme 

 imperfection. Though offering the results at present received as most 

 trustworthy, a very superficial examination will show how full they are 

 of errors and contradictions. Perhaps it would not be too much to say 

 that it will require the labor of many physicians, continued for centuries, 

 to bring such tables to the truth. Yet the approach to precision in these 

 hypothetical constants will in all times be a measure of the exactness of 

 physiology, and it may be added, also, of the practice of medicine. The 

 time is at hand when such a typical standard must be the starting-point 

 for pathology, and no rational practice can exist without it. The passage 

 of physiology, from a speculative to a positive science, is the signal for a 

 revolution in the practice of medicine. 



Moreover, physiology should furnish formulas for the computation of 

 variations in these tabular numbers under variable conditions ; as, for in- 



