Resin Soaps. 85 



3. Ten pounds whale-oil or other soft soap, 2 or 3 pounds 

 sulphur, 1 gallon coal oil, 17 gallons water. 



It will be seen that soap or kerosene, or both, formed the 

 basis of most of these washes. They were not entirely satis- 

 factory, for some reason still unexplained. In 1886, D. W. 

 Coquillett and Albert Koebele, were appointed by the Depart- 

 ment of Agriculture to investigate the trouble, for in the East 

 such emulsions were used almost invariably with good results. 



In a review of their work, published in 1887, Dr. Riley makes 

 the following statements, which indicate well the character of 

 these investigations : 1 



" Among the different substances thoroughly experimented 

 with were caustic potash, caustic soda, hard and soft soaps, 

 tobacco soap, whale-oil soap, vinegar, Paris green, resin soaps, 

 and compounds, and so on. . . . Mr. Koebele's attention was, 

 however, directed mainly to the preparation of resinous soaps 

 and compounds on account of their greater cheapness. He suc- 

 ceeded in making a number of these mixtures, which, when 

 properly diluted, need not cost more than one-half to one cent 

 per gallon, and which produce very satisfactory results, killing 

 the insects or either penetrating or hardening the egg masses 

 so as to prevent the hatching of the young. One of the most 

 satisfactory methods of making a resin soap is to dissolve 1 

 pound of caustic soda in 1^ gallons water to produce the lye ; 

 then dissolve 2 pounds resin and 1 pound tallow by moderate 

 heat, stirring in gradually during the cooking 1 quart of the 

 lye, and then adding water until you have about 22 pints of 

 a brown and thick soap- This will make 44 gallons of wash, 

 costing less then one-half cent per gallon." 



A few further suggestions were made regarding various 

 combinations of the above mixture, and the addition of adhesive 

 substances to the washes was strongly advised. But the most 

 important part of this address was the emphasis laid upon the 

 value of the resin washes, for from this time on they were destined 

 to extensive use in the orange district of California. 



1 Address by Professor C. V. Kiley before the California State Board of Horticul- 

 ture, at its seini-annual session at EiA-erside, Cal., April 12, 1SS7, as reported in the 

 Pacific Rural Press, April 23, 1887, cited in Bull. 15 U. S. Dept. of Agrie. Div. 

 of Ent. 16, 17. See also Ann. Hept. U. S. Com. of Ayric. 1SS6, 558, giving details 

 of Koebele' s work. 



