35 



Thinking the subject worthy of investigation, I made a few experi- 

 ments with this substance, but the results were far from being satis- 

 factory. I dissolved the sublimate in cold water by frequent stirring ; 

 this required about 15 minutes, aud the solution was of a dark bluish- 

 gray color. Following is a brief account of these experiments : 



(224) Corrosive sublimate, 2£ ounces ; water 100 gallons. Sprayed 

 on an orange tree infested with the red scale at 3 p.m., October 10, sun 

 shining, light breeze. November 13, leaves and fruit uninjured ; found 

 great many living red scales on this tree. 



(223) Corrosive sublimate, 4J ounces ; water, 100 gallons. Sprayed 

 on an orange tree at 2:30 p. m., October 10, sun shining, light breeze. 

 November 13, leaves aud fruit uninjured ; found great many living red 

 scales on this tree. 



(236) Corrosive sublimate, 1-J- pounds; water, 100 gallons. Sprayed 

 on a dormant pear tree infested with the San Jose scale at 10 a. in., 

 December 31, sun shining, light breeze. February 3, found a great 

 many living San Jose scales on this tree. 



The price in this city of the corrosive sublimate in 10-pound lots is 

 at the rate of $1.40 per pound; at this rate the strongest solution I 

 used (experiment 236) would cost about $1.63 per 100 gallons. I did 

 not test a stronger solution than this, since its cost alone would prevent 

 its being extensively used. 



Glue. — For the purpose of testing this substance as an insecticide 

 for the destruction of the red scale on citrus trees I made a few experi- 

 ments with it, but with very unsatisfactory results. The grade I used 

 is of a light brown color, not the white, nor yet the poorest grade, but 

 such as is used by cabinet-makers. To dissolve the glue I simply boiled, 

 it in water, and it dissolved in about 10 minutes. Following is a brief 

 account of these experiments : 



(227) Glue, 4 J pounds ; water 100 gallons. Sprayed on an orange 

 tree infested with the red scale at 4:30 p. m., October 11, sun shining, 

 light breeze. November 13, leaves and fruit uninjured; found great 

 many living red scales on this tree. 



(226) Glue, 8.1 pounds ; water 100 gallons. Sprayed on an orange 

 tree at 4 p. in., October 11, sun shining, light breeze. November 13, 

 leaves and fruit uninjured; found great many living red scales on this 

 tree. 



(225) Glue 12J pounds; water 100 gallons. Sprayed on an orange 

 tree at 3:30 p. in., October 11, sun shining, light breeze. November 13, 

 leaves and fruit uninjured; found great many living red scales on this 

 tree. 



In this city (Los Angeles) the price of glue of the above grade in 10- 

 pound lots is at the rate of 50 cents per pound; at this rate the strongest 

 solution I used (experiment 225) will cost $6.25 per 100 gallons. This, 

 of course, is much too expensive for ordinary use as an insecticide, and 

 for this reason I did not test a stronger solution. 



