October 20, 1911] 



SCIENCE 



499 



come by methods useful in keeping the 

 body in healthful activity, by regulation 

 of the diet, sleep, air, bathing, exercise and 

 mental recreation. This type of medicine 

 was brought to a high stage of develop- 

 ment by the Greeks, among whom personal 

 hygiene was practised to a degree of per- 

 fection which it has never elsewhere 

 reached. To Hippocrates are ascribed the 

 works in which the hygienic medicine of 

 the Greeks is summarized. It has formed 

 the basis of much of the best medical prac- 

 tise ever since. If, however, as some his- 

 torians believe, the decline of Greece was 

 due in large part to malaria, the Greeks in 

 the end served to illustrate the inadequacy 

 of merely hygienic medicine. 



Physiologic medicine is based upon cen- 

 turies of study of the structure and func- 

 tions of the body in health and disease. It 

 began among the Greeks soon after the 

 time of Hippocrates and reached its high- 

 est development during the nineteenth cen- 

 tury. It seeks to determine accurately just 

 what structural or functional disturb- 

 ances underlie the symptoms of a given 

 disease, to what extent the disturbances 

 are beneficial and to what extent detri- 

 mental, and what may be done to allay 

 the detrimental and excite the beneficial 

 disturbances. It has given rise to re- 

 fined methods of diagnosis so that lesions 

 of the heart, the lungs, the kidneys 

 and other vital organs may be deter- 

 mined with considerable accuracy, and 

 steps taken so far as possible to overcome 

 these defects by use of drugs, operations 

 or carefully regulated habits of living. It 

 has shown that not all symptoms of disease 

 are signs of an injured mechanism, but 

 rather may frequently be signs of a vigor- 

 ous healthy fight against invasion. Thus 

 fevers are frequently, if not always, accom- 

 panied by the production of living cells or 

 of chemical substances which attack invad- 



ing disease germs. The fight may be lost 

 and the mechanism may be permanently 

 damaged, but on the other hand the fight 

 may be won. That a fight won against a 

 mild invader may enable the body to resist 

 a stronger one was shown in the latter part 

 of the eighteenth century by Jenner, who 

 discovered that inoculation with cowpox 

 will protect against smallpox. This great 

 discovery of vaccination soon proved a 

 blessing to mankind, but nearly a century 

 passed before scientific knowledge and 

 methods became sufficiently developed to 

 give us the Pasteur treatment for rabies, 

 the Behring serum treatment for diph- 

 theria, and the opsonic therapy of Wright, 

 all based upon the idea either of stimula- 

 ting the normal power of the body to re- 

 sist disease or of stimulating an animal to 

 resist disease and then utilizing its resist- 

 ance products by injecting them into the 

 human body. These biological methods of 

 treating infectious or contagious diseases 

 are to be contrasted with the merely chem- 

 ical methods of which until recently but 

 two were known to be specific : mercury in 

 syphilis, derived from the Arabian use of 

 the drug in cutaneous affections, and qui- 

 nine in malaria, derived in the eighteenth 

 century from the use by natives of Peru 

 of Peruvian bark to cure fevers. Recently 

 the genius of Ehrlich has enabled him to 

 add at least one new specific drug, another 

 cure for syphilis, and to open a new field 

 for work. 



In another direction physiological re- 

 search has shown that when an organ 

 whose secretions are needed for normal ac- 

 tivities is deficient its place may sometimes 

 be taken by extracts from organs of the 

 lower mammals. The use of thyroid ex- 

 tract in cretinism and myxcedema is one 

 of the greatest gifts of physiology to medi- 

 cine. Nothing is more astonishing than the 

 development of a cretin, otherwise des- 



