WAR SERVICE OF MEDICAL PROFESSION 281 



The response of the medical profession to the call of the 

 Government was at all times sufficient for our needs, and in 

 addition permitted us to loan medical officers to our Allies in 

 considerable numbers, particularly to Great Britain. 



The wastage or losses from all causes during the period of 

 our participation in the war, was about ten thousand or one- 

 quarter of the total names on the rolls. 



SANITARY ENGINEERING PROBLEMS AT HOME AND ABROAD 



In home territory in all large National Army and National 

 Guard camps good potable water was provided, where possible 

 by purchasing treated water from a nearby city, but when this 

 was not feasible a complete water supply system was installed 

 at the camp itself. This usually consisted of an impounding 

 basin for the collection and sedimentation of the raw water, 

 which was then filtered in some form of rapid sand filter after 

 dosing with alum or other suitable coagulant, to throw down 

 all suspended matter. Finally, at practically every place, the 

 clear water was then treated with anhydrous chlorin gas, which 

 disinfected the water by oxidizing all organic matter. 



In smaller places, the question of water purification was 

 less satisfactorily answered. The Lyster bag method of chlori- 

 nation was the standard. The chlorin was added to the raw 

 water, in the form of bleaching powder, which was put up 

 in small measured quantities, in glass ampuls. The bag itself 

 is made of strong canvas and is attached to a folding iron ring 

 at the top. At the sides a little above the bottom, high enough 

 to avoid the sediment which falls gradually to the lowest point, 

 are several simple faucets from which the water is drawn off 

 to fill canteens and other pure water containers. 



The control of successful water sterilization by means of 

 chlorin is fortunately a simple "mailer, consisting merely in a 

 test for free chlorin by means of the starch iodine test. This 

 is made thirty minutes after the bleaching powder has been 

 added to the water in the Lyster bag, by taking a large cupful 

 and adding to it 10 drops of a 10 per cent, solution of iodide 



