77 
what less than that of the ordinary ''Oregon wash." "Calcothion" 
is appHed as received, without either additional preparation or dilu- 
tion. It has the disadvantage of a high cost, amounting to $5 per 
hundred gallons. 
8. Minor experiments with several additional insecticides are 
briefly described on pages 72 and 73. 
9. The expense of preparation of the mixtures to be dissolved 
by boiling is so variable, according to the amount to be used, the 
supply of available labor, and the kind and cost of fuel, that no at- 
tempt has been made to estimate it. For all the lime and sulphur 
solutions except those made with soda, and for whale-oil soap, it 
amounts virtually to the cost of boiling successive quantities of fifty 
gallons of water, each for 30 to 45 minutes. 
