InSe:CTS and INS13CTICID15S 
49 
Reading on Hydrometer, Specific 
Degree Baume. gravity. 
35 1.3181 
34 .. . . 1.3063 
33 1.2946 
32 . 1.2831 
31 1.2719 
30 1.2608 
29 1.2500 
28 1.2393 
27 . 1.2288 
26 1.2184 
25 1.2083 
24 . 1.1983 
23 1.1885 
22 1.1788 
21 . 1.1693 
20 . 1.1600 
19 . 1.1507 
18 1.1417 
17 . 1.1328 
16 1.1240 
15 . 1.1153 
With each gallon of concentrate 
use 
for San Jose Scale 
9 
gallons water 
814 
gallons w'ater 
8 
gallons water 
TVa 
gallons water 
gallons water 
7 
gallons water 
6^ 
gallons water 
6^ 
gallons water 
6 
gallons water 
5H 
gallons water 
5^ 
gaBons water 
554 
gallons water 
454 
gallons water 
4^4 
gallons water 
4^ 
gallons water 
4 
gallons water 
3 2y3 gallons water 
3 ly3 gallons water 
3 gallons water 
2 4y5 gallons water 
2J4 gallons water 
i 8 . Tobacco 
Tobacco in one form or another has come to be one of the most 
generally used and the most effective insecticides. In the shape of 
a fine powder it is sometimes used against flea-beetles; the dust made 
from the stems is one of the b'St remedies we have for woolly aphis 
on the roots of the apple trees. 
19 . Tobacco Extracts 
There are several commercial tobacco preparations on the market. 
Those most generally used are ‘'Black Leaf 40” and “Nicofume.’' 
These both contain about 40 percent nicotine which is the poisonous 
principle in tobacco. This is one of the most deadly poisons known. 
It is soluble in water and entirely volatile when pure. In Black Leaf 
40, the nicotine has been treated to form a sulphate which is nonj- 
volatile. Black Leaf 40 is used in strengths varying from i part 
to 800 parts of water to i part to 1200 parts. Three pounds of soap 
added to each 100 gallons will make it spread and stick better. When 
used against the woolly aphis, the soap will aid the mixture to pene¬ 
trate the woolly covering of the lice. 
Black Leaf 40 can be combined with arsenate of lead and lime- 
sulphur sprays, but should not be used with ars^nite of zinc. 
Nicofume is us-^d almost entirely for green-house insects. The 
nicotine being volatile, it will not stay on th“ plants long. 
Its principal use is to soak material from which a smudge is made. 
The nicotine is driven off and destroys the insects. 
Tobacco decoction is sometimes made by st'^eping one pound of 
tobacco in 4 or 5 gallons of water. Do not boil, as this will vola¬ 
tilize the nicotine. 
