NOVEMBEK 25, 1904.] 



SCIENCE. 



109 



did much to bring certainty and precision 

 into a field in which many had gone astray, 

 while opening the way for the important 

 observations of Theobald Smith and all the 

 knowledge which we have gained in recent 

 years with regard to the hsematozoa of 

 man and animals. 



As a direct result of the introduction of 

 bacteriological methods, the study of the 

 manner of action of infectious agents and 

 their toxic products upon the animal organ- 

 ism, as well as of the powers of resistance 

 of the economy against infection, has given 

 us, with the discovery of specific agglu- 

 tinines and precipitines, diagnostic meth- 

 ods of the greatest value, not only for the 

 recognition of various infectious processes, 

 but for the identification of specific sera, 

 affording in particular a test for hiunan 

 blood destined, probably, to prove, when 

 properly applied and interpreted, of great 

 medico-legal value. 



This is, indeed, a gain over our knowl- 

 edge of one hundred years ago. In 

 how~ many fields has the conjectural 

 given way to the exact! At the end of 

 the eighteenth century the diagnostic ef- 

 fort of the physician, unaided by instru- 

 ments of precision or even by the simplest 

 physical methods of auscultation and per- 

 cussion, was directed toward the detection 

 of gross anatomical changes. To-day with 

 our increased knowledge of anatomical, 

 physiological and pathological processes, 

 with our growing insight into the chemical 

 and physical features of vital activity, our 

 duty no longer ends in the recognition of 

 physical changes in organs, in the deter- 

 mination of the presence of a specific lesion 

 or infection; it is, further, our task to 

 search for the earliest evidence of disturb- 

 ance of function which may later lead 

 to grosser, more evident change, to sepa- 

 rate the physiological from the patholog- 

 ical, to estimate, as far as may be, the power 

 of resistance of the different organs and 



tissues and fluids of the body to insults of 

 varying nature, to determine the functional 

 capacity of a given organ— its sufficiency 

 or insufficiency. In addition to increasing 

 opportunities in the field of pathological 

 anatomy we find ourselves drawn further 

 into the study of pathological physiology — 

 and kgaowledge in the field of pathological 

 physiology leads of necessity to power in 

 functional diagnosis. 



It must be acknowledged that with re- 

 gard to many organs the determination of 

 the limits of functional power and the esti- 

 mation of the degree of impairment in dis- 

 ease, are matters most difiicult to appre- 

 ciate, yet with improved methods and per- 

 sistent research progress is being made. 



We are, after all, but beginning to realize 

 a few of the possibilities before us, but 

 even this is a step in advance which holds 

 out no little promise for the future and 

 oft'ers new and tempting opportunities for 

 study and investigation. 



At the end of the eighteenth century but 

 three important, rationally conceived meas- 

 ures of prophylaxis had been practised — 

 the dietetic measures of protection from 

 scurvy, the older inoculation and Jenner's 

 great contribution of vaccination against 

 small-pox. It was not, indeed, until the 

 development of bacteriology that prophy- 

 laxis took its place as a scientifically exact 

 branch of medicine. The recognition of 

 the specific cause of many infectious dis- 

 eases, the knowledge of the life history of 

 the pathogenic micro-organisms, the discov- 

 ery of the portals through which they gain 

 entrance to the animal economy, and the 

 conditions under which infection occurs, 

 have brought to us material powers to pre- 

 vent and protect. The first great result of 

 this new knowledge was the development 

 of antiseptic surgery and all that it repre- 

 sents. But apart from this we have but 

 to remember what has been gained by a 

 scientifically evolved prophylaxis against 



