CAUSES OF INSANITY 557 



TWO PREVENTABLE CAUSES OF INSANITY 



By De. THOMAS W. SALMON 



PASSED ASSISTANT SUEGEON, U. S. PUBLIC HEALTH AND MAEINE HOSPITAL SEETICE 



A FEW successful skirmishes in the interminable conflict with dis- 

 ease happened to take place recently on American soil. We 

 saw the weapons of defense which scientific research had forged for us 

 valiantly wielded by some of our countr}nmen and a new interest in 

 preventive medicine, which has spread far beyond the ranks of the 

 medical profession, was the result. Such discoveries as the detection 

 of the part played by the mosquito in the transmission of yellow fever 

 and by the rat flea in the spread of bubonic plague were interesting 

 enough to gain a place in the news of the day but it was the fact that 

 the first demonstrations of their surpassing practical value were given 

 by medical officers of the American Army and Marine Hospital Serv- 

 ice in our own land that gave rise to the present widespread confidence 

 in the achievements possible in the domain of public health. It is 

 natural, perhaps, that this newly awakened interest in the prevention 

 of disease should center in the infectious diseases, in which the rela- 

 tion between cause and effect is often so obvious and the means of pre- 

 vention are so logical. The school children of New Orleans easily 

 grasped the simple facts in the case against the yellow-fever mosquito 

 and they became efficient recruits in the memorable campaign of 1905. 

 Much of the success in the present general movement against tubercu- 

 losis, the most formidable of all our unseen foes, is due to the fact that 

 nearly all we know of its transmission can be reduced to half a dozen 

 maxims, each of which can be expressed in as many words. It would 

 be unfortunate, however, if popular interest in the battles for the pub- 

 lic health should not extend to those diseases in which the relation 

 between cause and effect is one step farther removed. 



It is essential that the front presented to the common enemy 

 should be as wide as our present knowledge justifies. There need be 

 no fear of disaster from advancing in extended order, for an attack 

 upon one position of the adversary will not infrequently disclose an 

 unsuspected weakness in another. Since May, 1907, every effort has 

 been made by the combined federal and city forces to rid San Fran- 

 cisco of bubonic plague. With victory assured, the results of what has 

 been done are being counted up and it is found that measures under- 

 taken for the extermination of plague have brought about a sanitary 



