none the less there are certain well-organized and efficiently operated agencies which have for their function the improvement of public hygiene and sanitation, the eradication of preventable disease, and the study of causation and methods of control of diseases. Most of these functions are exercised by the Public Health and Marine Hospital Service, which, strangely enough, constitutes a bureau under the Treasury Department. Some of this work is done under the Department of Agriculture, and other minor lines are scattered elsewhere through the national machinery. It is easily seen how much more efficient would be the work were all these agencies for national health protection united
under one administrative head, and their various activities carefully coordinated.
The Public Health and Marine Hospital Service operates all national quarantine stations where inspection is made for yellow fever, typhus fever, smallpox, bubonic plague, leprosy and cholera; maintains hospitals throughout the country for sailors of the American merchant marine; conducts the Hygienic Laboratory at Washington for the study of the causation and treatment of diseases; exercises numerous minor functions of a national board of health; and conducts the medical inspection of immigrants. Certain diseases are found so frequently among immigrants, and others are so inherently dangerous, as to merit special mention because of their important relation to public health.
First among these might be placed trachoma, a disease of the eyelids characterized by extreme resistance to treatment, very chronic course and most serious results. Most of the immigrant cases occur in Russians, Austrians and Italians, although it is of common occurrence in oriental and Mediterranean countries. It causes a large percentage of