SCIENCE. 



429 



these physiological units into an organic whole. In 

 fact, the body is a machine of the nature of an army, not 

 of that of a watch, or of a hydraulic apparatus. Of this 

 army, each cell is a soldier, an organ a brigade, the 

 central nervous system headquarters and field tel- 

 egraph, the alimentary and circulatory system the com- 

 missariat. Losses are made good by recruits born in 

 camp, and the life of the individual is a campaign, con- 

 ducted successfully for a number of years, but with cer- 

 tain defeat in the long run. 



" The efficacy of an army at any given moment de- 

 pends on the health of the individual soldier, and on the 

 perfection of the machinery by which he is led and 

 brought into action at the proper time ; and, therefore, 

 if the analogy holds good, there can be only two kinds of 

 diseases, the one dependent on abnormal states of the 

 physiological units, the other on perturbation of their 

 co-ordinating and alimentative machinery. Hence, the 

 establishment of the cell theory in normal biology was 

 swiftly followed by a ' cellular pathology ' as its logical 

 counterpart. I need not remind you how great an in- 

 strument of investigation this doctrine has proved in the 

 hands of the man of genius, to whom its development is 

 due, and who would probably be the last to forget that 

 abnormal conditions of the co-ordinative and distributive 

 machinery of the body are no less important factors of 

 disease. Henceforward, as it appears to me, the connec- 

 tion of medicine with the biological sciences is clearly 

 defined. Pure pathology is that branch of biology which 

 defines the particular perturbation of cell-life, or of the 

 co-ordinating machinery, or of both, on which the pheno- 

 mena of disease depend. 



" Those who are conversant with the present state of 

 biology will hardly hesitate to admit that the conception 

 of the life of one of the higher animals as the summation 

 of the lives of a cell-aggregate, brought into harmonious 

 action by a co-ordinative machinery formed by some of 

 these cells, constitutes a permanent acquisition of physio- 

 logical science. But the last form of the battle between 

 the animistic and the physical views of life is seen in the 

 contention whether the physical analysis of vital phenom- 

 ena can be carried beyond this point or not. 



" There are some to whom living protoplasm is a sub- 

 stance even such as Harvey conceived the blood to be, 

 summd cum providcntia et intellectu in finem cerium 

 agens, quasi ratiocinio quodam ; and who look, with as 

 little favor as Bichat did, upon any attempt to apply the 

 principles and the methods of physics and chemistry to 

 the investigation of the vital processes of growth, meta- 

 bolism, and contractility. They stand upon the ancient 

 ways ; only, in accordance with that progress toward 

 democracy which a great political writer has declared to 

 be the fatal characteristic of modern times, they substi- 

 tute a republic formed by a few billion of ' animulas ' for % 

 the monarchy of the all-pervading ' anima.' Others, on 

 the contrary, supported by a robust faith in the universal 

 applicability of the principles laid down by Descartes, 

 and seeing that the actions called ' vital ' are, so far as 

 we have any means of knowing, nothing but changes of 

 place of particles of matter, look to molecular physics to 

 achieve the analysis of the living protoplasm itself into a 

 molecular mechanism. If there is any truth in the re- 

 ceived doctrine of physics, that contrast between living 

 and inert matter, on which Bichat lays so much stress, 

 does not exist. In nature nothing is at rest, nothing is 

 amorphous ; the simplest particle of that which men in 

 their blindness are pleased to call ' brute matter ' is a vast 

 aggregate of molecular mechanisms, performing com- 

 plicated movements of immense rapidity, and sensitively 

 adjusting themselves to every change in the surrounding 

 world. Living matter differs from other matter in degree 

 and not in kind; the microcosm repeats the macrocosm ; 

 and one chain of causation connects the nebulous original 

 of suns and planetary systems with the protoplasmic 

 foundation of life and organization. From this point 01 



view pathology is the analogue of the theory of pertur- 

 bations in astronomy ; and therapeutics resolves itself 

 into the discovery of the means by which a system of 

 forces competent to eliminate any given perturbation may 

 be introduced into the economy. And as pathology 

 bases itself upon normal physiology, so therapeutics rests 

 upon pharmacology, which is, strictly speaking, a part of 

 the great biological topic of the influence of conditions 

 on the living organism, and has no scientific foundation 

 apart from physiology. 



" It appears to me that there is no more hopeful indi- 

 cation of the progress of medicine toward the ideal of 

 Descartes than is to be derived from a comparison of the 

 state of phaimacology at the present day with that which 

 existed forty years ago. If we consider the knowledge 

 positively acquired in this short time of the modus oper- 

 andi of urari, of atropia, of physostigmin, of veratria, of 

 casca, of strychnia, of bromide of potassium, of phos- 

 phorus, there can surely be no ground for doubting that, 

 sooner or later, the pharmacologist will supply the physi- 

 cian with the means of affecting, in any desired sense, 

 the functions of any physiological element of the body. 

 It will, in short, become possible to introduce into the 

 economy a molecular mechanism which, like a very cun- 

 ningly contrived torpedo, shall find its way to some par- 

 ticular group of living elements, and cause an explosion 

 among them, leaving the rest untouched. The search 

 for the explanation of diseased states in modified cell-life ; 

 the discovery cf the important part played by parasitic 

 organisms in the etiology of disease ; the elucidation of 

 the action of medicaments by the methods and the data 

 of experimental physiology — appear to me to be the 

 greatest steps which have ever been made toward the 

 establishment of medicine on a scientific basis. I need 

 hardly say they could not have been made except for the 

 advance of normal biology. 



" There can be no question, then, as to the nature or 

 the value of the connection between medicine and the 

 biological sciences. There can be no doubt that the 

 future of pathology and of therapeutics, and therefore that 

 of practical medicine, depend upon the extent to which 

 those who occupy themselves with these subjects are 

 trained in the methods, and impregnated with the funda- 

 mental truths, of biology. 



" And, in conclusion, I venture to suggest that the 

 collective sagacity of this Congress could occupy itself 

 with no more important question than with this. How 

 is medical education to be arranged, so that, without 

 entangling the student in those details of the systematist 

 which are valueless to him, he may be enabled to obtain 

 a firm grasp of the great truths respecting animal and 

 vegetable life, without which, notwithstanding all the 

 progress of scientific medicine, he will still find himself 

 an empiric ?" 



NOTES ON EXPERIMENTAL CHEMISTRY.* 

 By Professor Albert B. Prescott. 



I. Determinations of the limits of (1), temperature in 

 solution ; (2), temperature in dry state ; (3), alcoholic 

 fermentation ; and (4), acidity, compatible with the 

 starch converting power of diastase of barley malt. 



II. Determinations of the solubility of precipitated 

 aluminium hydrate in excess of ammonium hydrate, with 

 and without ammonium chloride. 



In a paper by M. L. Boudenoot in the Nouvclles Annates 

 de la Construction, describing the various forms of explosives 

 of the nitro-cellulose class, a new compound is mentioned, 

 called by its inventor, M. Anders, gclatino-diaspon. It is 

 composed of wood-cellulose and nitro-glycerine, is un- 

 affected by cold, is not sensible to blows or shocks, and 

 explodes only by a sudden increase of temperature to 

 about 160 C. (320 Fahr.) It burns quietly when ignited 

 in the open air, and is not injured by water. 



* Read before the A. A. A. S., Cincinnati, 1881. 



