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When rats affect human health, the United States Public Health Ser- 
vice is empowered to destroy thei at the centers of infestation. For many 
years that Service has superviced the fumigation of vessels arriving at our 
ports, and it makes pericdic examinations along the waterfronts to prevent 
the introduction of hubonic plague and other diseases. In most communities 
locai health officials are authorized +o take action against rats when they 
endanger public health. 
Such research in rat control has been carried on by the Bureau of 
Biological Survey as the funds have permitted. Prof. Lantz, who was con- 
nected with the Survey wntil his death in 1919, was one of the pioneers in 
this courtry in developing methods of rat control. In his first Farmers! 
Bulletin on the subject (No. 297), which appeared in 1907, he emphasized 
the need for cooperative effort, ratprocfing, sanitation, and various meth- 
ods of destruction, particularly ty the use of barium carbonate, then con- 
sidered the safest rat poison to handle. All aspects of the problem were 
studied by Prof. Lantz, and his findings were given to the public through 
demonstrations and in bulletins issued by the Bureau. Upon his death, 
James Silver undertook the work, and it is now being continued in the Div- 
ision of Predator and Rodent Control of the Biological Survey. 
In 1920, the Federal Bureau of Chemistry published a technical bul- 
letin on the "Toxicity of Parium Carbonate to Rats," and in 1922, one on 
the "Relative Toxicity of Strychnine to the Rat." 
In later years it was felt that the public should employ a safer pdi- 
son than any of those then in common use. Zxperiments were begun to develop 
& satisfactory red-squill powder, as European preparations containing this 
product were not of uniformly high toxicity. After testing red-squill pow- 
ders manufactured by different processes on about 10,000 rats, a satisfac- 
tory method of producing a highly efficient product was developed by the 
Biological Survey in 1929, and the results were published in a technical 
bulletin, "Red-Squill Powders as Raticides." Further investigations with 
the preparation are now being conducted, including the manufacturing of 
squill extract and isolation of the specific principle toxic to rats. The 
Survey is continually experimenting to develop nev and improved raticides. 
_____.. _The educational phase of rat control has been promoted by issuing 
timely bulletins, news articles, and radio addresses, and making lantern 
Slides, motion pictures, and posters available to the public. The material 
for these media of information is based on facts, rather than on theories. 
Various methods of rat destruction now in use need further study because 
of insufficient demonstration of their value; the use of "lures" is one 
example, 
Although the research and educational aspects of the rat problem are 
of fundamental importance, the chief need is to stimulate cooperative 
efforts. As is well realized, a Nation-wide rat-control program is one 
that requires everyone's cooperation. [% calls for concerted efforts by 
Federal, State, and local officials. Rats are roving animals and their 
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