75 
summaries, with the exception of those used in certain minor experi- 
ments, which have been separately given. This cost, stated in 
terms of one hundred gallons of the spray diluted and otherwise 
made ready for actual distribution, is based on the following rates 
for materials, which are those actually paid by us, or, in a few minor 
cases, those furnished us by the manufacturers. None of these 
prices includes freight. 
Lime. 90 cents per bbl. of 196 lbs. 
Sulphur. $2.30 per cwt., bought in ton lots. 
Salt. 33 cents per cwt., by the bbl. 
Blue vitriol. $6 per cwt. 
Caustic soda. $4.50 per cwt., in 10-lb. cans. 
Whale-oil soap. 4 cents per lb., by the bbl. 
Tak-a-nap soap. 5 certs per lb., in 40-lb. packages. 
Kerosene. 12% cents per gal., by the bbl. 
Marblehead hydrated lime No. 1. 50 cents per cwt. 
" " " " 2. 50 cents per cwt. 
Wisconsin limate. 50 cents per cwt. 
Delaware limoid. Highest grade, $5. per bbl. of 200 lbs.; cheaper 
grade, $2.50 per bbl., or $14. per ton. 
Calcothion. 5 cents per gal., if bought by the bbl. 
Con Sol. $1. a gal. 
Frutolin. 66 cents per liter (1.06 quarts) in cases, each containing a 
dozen liter cans. 
Scalecide. 50 cents per gal., in 50-gal. bbls. 
The cheapest of these washes, counting cost of materials only, is, 
■fortunately, the one found most efficient in these experiments, 
namely, the simple lime and sulphur wash in the ratio of 15, 15, 50, and 
costing 84 cents per 100 gallons when ready for spraying. The next 
in order is the common "California wash" of lime, sulphur, and salt 
(15, 15, 15, 50), costing 94 cents per hundred gallons. The "Ore- 
gon wash" made by the old formula still in most general use, and 
containing 15 pounds of lime, 15 pounds of sulphur, and ij^ pounds 
of blue vitriol to 50 gallons of water, costs $1 per hundred gallons; 
and the simple lime and sulphur mixture with 21 pounds of lime 
and 18 pounds of sulphur to 50 gallons, costs $1.03. The "Oregon 
wash" with the lime (of whatever form) increased to 20 pounds, 
amounts to $1.07 per hundred gallons; and the lime and soda 
washes, from $1.24 to $1.44, dependent upon the proportions of the 
ingredients as given in Table I., Experiments 10 and 11. 
The next in order of cost is "Con Sol," at $2.40 per hundred gal- 
lons, I part of the insecticide to 40 of water; and then "Scalecide," 
$2.50 per hundred gallons, when used in a 5 per cent, solution. The 
kerosene emulsions made with hydrated lime and diluted to contain 
