550 



MEDICAL SCIENCE AND PEACTICE. 



definitely. They may have no noticeable influ- 

 ence on the general economy, or they may 

 favor it. On the other hand, they may be of 

 such a nature as to impede the activities of the 

 organism, or even involve its destruction." In 

 the first case, these perturbations are styled 

 " variations " ; in the second case, they are 

 cal led lesions, states of poisoning, or diseases, 

 and, as morbid states, lie within the province 

 of pathology. No sharp line of dernarkation 

 can be drawn between the two classes of phe- 

 nomena, and all that can be said is, that what- 

 ever change of structure or function is hurtful 

 belongs to pathology. Hence, pathology is a 

 branch of biology the morphology, the physi- 

 ology, the distribution, the etiology of abnor- 

 mal life. 



"The search,'' says Professor Huxley, "for 

 the explanation of diseased states in modified 

 cell-life; the discovery of the 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." 

 Medicine, however, has presented two aspects 

 the scientific and the empirical the differ- 

 ence between which lies in the very nature of 

 things. "While there is so much that is un- 

 known in the study of medicine, there must be 

 empiricism in its practice. Knowing little or 

 nothing of certain processes of disease, it is 

 guided by broad results, and that is empiricism. 

 Knowing, from previous investigation, some- 

 thing of certain other processes, it is guided 

 by its knowledge of their causation, and that 

 is scientific medicine. The possible area of em- 

 piricism can be more circumscribed only with 

 the advance of biology ; and, with the better 

 means thus afforded to test and investigate its 

 assertions, they will be the more quickly re- 

 duced to scientific expression. Medicine thus 

 can claim an independent existence as a prac- 

 tical science not, of course, independent of 

 biology, but taking rank as one of its distinct 

 and integral divisions. Intimately related to 

 its sister-divisions, and freely giving to and 

 borrowing from them, it yet lives and works in 

 a sphere of its own. 



Pathology, in the sense that it is the mor- 

 phology of abnormal life, is pronounced by 

 Professor Huxley the analogue of the theory 

 of perturbations in astronomy ; and from this 

 point of view therapeutics resolves itself into 

 the discovery of the means by which a system 

 of forces competent to eliminate any given per- 

 turbations may be introduced into the econ- 

 omy. And, as pathology is based on normal 

 physiology, so therapeutics rests upon phar- 

 macology, which is, strictly speaking, a part of 

 the great biological topic of the influence of 

 conditions on the living organism. Most hope- 

 ful indications of the progress of medicine are 

 derived from a comparison of the state of phar- 

 macology at the present day with that which 



existed forty years ago. If we consider, Pro- 

 fessor Huxley says, the knowledge positively 

 acquired, in this short time, of the modus ope- 

 randi of urari, of atropia, of physostigmin, of 

 veratria, of casca, of strychnia, of bromide of 

 potassium, of phosphorus, "there can surely be 

 no ground for doubting that, sooner or later, 

 the pharmacologist will supply the physician 

 with the means of affecting, in any de.Mivd 

 sense, the functions of any physiological ele- 

 ment of the body. It will, in short, become 

 possible to introduce into the economy a mo- 

 lecular mechanism which, like a very cunningly 

 contrived torpedo, shall find its way to some 

 particular group of living elements, and cause 

 an explosion among them, leaving the rest un- 

 touched." 



The advancement of medicine within the last 

 generation has been marked, first, in its devel- 

 opment from within of its own art and science ; 

 secondly, in its adaptation and absorption of 

 means and principles of other arts and sciences ; 

 and, thirdly, in the simple adoption and applica- 

 tion of material from external sources, and may 

 be considered under all of these heads. In the 

 first branch of the subject absolute progress 

 has been made in our time in pathology, or 

 the knowledge of the nature of diseases, in the 

 study of their signs and symptoms, or semei- 

 ology, and in their treatment, or therapeutics. 



The most important step in pathology has 

 been the adoption of Virchow's doctrine of 

 cell-growth, to which the largest proportion 

 of recent progress has been directly or indi- 

 rectly owing. Great and important in itself, 

 and in its influence on biology generally, it 

 has little less than revolutionized patholog- 

 ical study. In its light pathological anatomy 

 has been studied as affording the efficient ex- 

 planation of morbid processes; the structure 

 of the tissues and organs in which disease pre- 

 vails has been exposed, and a distinct structural 

 basis has been given to our knowledge, if not 

 of the disease itself, of the morphological result 

 of the disease, which has yielded a precision and 

 definiteness such as no other conception could 

 yield; new light has been thrown upon the 

 clinical recognition of morbid processes ; forms 

 of disease which were semeiologically indis- 

 tinguishable, but pathologically distinct, have 

 been discriminated and individualized ; specific 

 varieties of the same type of disease have been 

 recognized from their commencement, and dis- 

 tinguished throughout their course ; constant 

 phenomena previously remarked have been 

 elucidated ; large and important classes of mor- 

 bid processes, before hardly recognized, have 

 been demonstrated ; the processes of every dis- 

 ease have been investigated, with general in- 

 crease of knowledge ; prognosis has been given 

 certainty and definiteness, and it has been pos- 

 sible to make an exact interpretation of the 

 morbid signs observed. A tendency has been 

 manifested in late years to supplement the 

 analytical method, which, useful and necessary 

 as it is, had been carried to an extreme, and 



