13 



Surgeon llosenau discusses the bacterial viruses in relation to rat 

 destruction. As a result of his investigations in the hygienic 

 laboratory and the reports of investigations and practical use else- 

 where, he concludes that the bacterial viruses have signally failed 

 t<> accomplish the mission for which they were intended, and that 

 they are not entirely harmless to man, as has been stated. 



Passed Assistant Surgeon Heiser briefly outlines the measures re- 

 commended for the eradication of plague in cities by means of sec- 

 tional extermination of rats and general rat proofing. He gives re- 

 sults following this method of procedure in Manila, and presents 

 charts showing how to deal with infected city districts. 



Passed Assistant Surgeon Hobdy, in a chapter on the rat in relation 

 to shipping, refers to the voyage-making tendencies of the rodent, 

 its destructiveness aboard ship, and its power of adapting itself to 

 unusual conditions and surroundings. In one small lumber vessel 

 fumigated by Doctor Hobdy at the Angel Island quarantine station 

 there were collected 525 dead rats. Mention is also made of 

 another vessel on which were collected 1,700 rats after fumigation, 

 lie discusses the methods by which it gains access to vessels, and out- 

 lines the practices that should be observed to keep it off. He also 

 describes in some detail the measures to be adopted for its de- 

 struction after it has gotten aboard ship, and mentions the differ- 

 ent methods of fumigation. 



Mr. Lantz, in a third paper, discusses the rat as an economic factor, 

 and states in his paper that they do not serve any useful purpose. 

 On the other hand, they cause enormous loss through damage to 

 grain, merchandise, poultry and eggs, game and wild birds, fruit and 

 vegetables, and flowers and bulbs. They also cause damage by 

 setting fire to buildings and destroying furniture. He refers to vari- 

 ous estimates made of the losses in the United States from rats, and 

 they vary from $35,000,000 to $50,000,000 a year; but at the same 

 time he states that, with present information, any attempt to state 

 the amount of loss from rats would be largely guesswork. 



Assistant Surgeon-General Kerr refers to the rat as a factor in inter- 

 national sanitation, and briefly outlines the provisions contained in 

 international sanitary agreements for their eradication. He reviews 

 the efforts being made at the more important seaports to exterminate 

 rats, as well as the methods being employed to that end. The infor- 

 mation presented is, in part, compiled from consular reports received 

 through the Department of State. There are given, so far as obtain- 

 able, copies of laws and ordinances enacted for the destruction of 

 rats and the different methods practiced in ports where plague has 

 prevailed, and the facts presented indicate that a more or less wide- 

 spread crusade against rats is being carried on. He expresses the 

 belief that it is too much to expect that the rat population can ever 



