APPENDIX 479 



Pyrethrum has a very feeble action on lice, while boric acid, sulphur, corrosive 

 sublimate, and zinc sulphate, when used in powder form, have apparently no action 

 whatever. As regards bedbugs, kerosene oil is the best insecticide. Next to it 

 comes guaiacol, one of the most active drugs of those tried. 



2. For use against lice on a large scale, as among troops and prisoners, perhaps the 

 best insecticide powder is naphthaline. This substance has a lower licecide action 

 than kerosene oil, guaiacol, iodoform and anise preparations, but it has less 

 displeasing odor than the first three named. In stored blankets and clothing 

 it is also practicable and of use, as frequently lice are found upon the clothing 

 and blankets stored through the summer. 



Medical Director H. G. Beyer, U. S. N., gives the following description of the 

 method of louse destruction employed by Lenz at the prison camp at Puchheim. 

 On the arrival of a large transport of prisoners, the clothes they wear on their persons 

 are, first of all, subjected to steam-disinfection, whereby a great mass of lice, includ- 

 ing eggs, are destroyed. The hair on the bodies of the men is then shorn with a 

 machine, and they are lathered over with soft soap and put into a bath. The now 

 disinfected clothes are put on again and treatment with naphthalin is begun under 

 the supervision of the sanitary police. Every person, at bedtime, has a handful of 

 finely powdered naphthalin put into his clothes, introduced through the opening 

 at the neck. He is made to sleep that night with all his clothes on him. The body 

 heat causes the naphthalin to evaporate, the vapors killing not only the remaining 

 lice, but also most of the remaining eggs. If this treatment is repeated twice more, 

 regardless of whether living lice are found or not at the time, a thorough and com- 

 plete louse disinfection will be assured. Lenz does not mention any disagreeable 

 effects of the naphthalin vapors on the men themselves. When dealing with trans- 

 ports of smaller numbers of individuals, Lenz states that he has succeeded even 

 without the employment of steam-sterilization of the clothes. The advantages 

 of the naphthalin method as used by him are given as follows: 



1. That it is cheaper than any other method, its cost per person being \y cents. 



2. That it does not interfere with the service efficiency of the men. 



3. That it requires neither special apparatus nor places. 



4. That it does not injure clothing. 



5. That it is absolutely noninjurious to the health of the men. 



Raticides. For exterminating rats and in this way secondarily the rat-fleas, be- 

 sides the ordinary poisons such as As, P, etc. Rucker has recommended a poison 

 composed of plaster of Paris, 6 parts, pulverized sugar i part and flour 2 parts. This 

 mixture should be exposed in a dry place in open dishes. To attract the rats the 

 edge of the dish may be smeared with the oil in which sardines have been packed. 



Larvicides. Wise and Minett report good results from the use of crude carbolic 

 acid as a larvicide for mosquitoes. They added about i teaspoonful for each 2 

 cubic feet of water in the pool. Of course, the ordinary method for destroying mos- 

 quito larvae is by covering the surface of the water in the cistern or pool with a layer 

 of petroleum. 



I ANATOMICAL AND PHYSIOLOGICAL NORMALS 



In examinations in the pathological or chemical laboratory the following may be 

 considered approximately as normal findings: 



