(January 19^1) for considerable quantities are as follows: sodium 
fluoride, 7~l/2 to 8-1/2 cents per pound; monoammonium phosphate, 8-1/2 
to 9-1/2 cents per pound; borax, 2-1/2 to 3 - l/2 cents per pound. Retail 
prices, which would include shipping costs, might "be considerably higher, 
Special Treatment Against Rats 
The following is quoted from a memorandum from the Fish and Wild- 
life Service (formerly Bureau of Biological Survey) : 
"It is found that rats are prone to nest in available 
walls filled with sawdust or wood shavings, provided, of 
course, the nearby environment is otherwise favorable. It 
has recently been learned that it may be possible to prevent 
this disturbance to sawdust to a considerable extent by blend- 
ing with it powdered copper carbonate, using 12 pounds in each 
100-rtound mixture. 
"This preparation may be mixed with treatment A when it 
is either wet or dry. It may mix more uniformly, however, 
following the drying process." 
"Attention is called to Farmers' Bulletin 1638, "Rat Proofing Build- 
ings and Premises," and Conservation Bulletin 8, "Rat Control," which can 
be obtained for 5 cents each from the Superintendent of Documents, Govern- 
ment Printing Office, Washington, D. C. (stamps not accepted)." 
R1092 -U- 
