8° 
tape line. This can be done by attaching the free end of the tape to 
a twig and passing around the tree, hanging the tape on the outer 
twigs as it is unreeled. If the grove consists of two sizes of trees, as, 
for example, large seedling and medium-sized budded trees, an aver- 
age specimen of both kinds should be measured. The amount of 
cyanid required for these average specimens can be determined from 
the dosage table given herein. The following examples illustrate the 
method of using the table after the distance over and the circum- 
ference of the tree have been obtained: 
} 
| Amount of | 
Example | Distance  Circumfer- | potassium 
No. | over tree. enceoftree. cyanid 
| required. | 
Feet. Feet. | Ounces. | 
1 24 40 | 9 | 
2 38 55 26 
3 52 72 58 
4 66 | 79 96 
The amount of cyanid in ounces having been obtained for the aver- 
age tree in the grove, this amount is multiplied by the total number of 
trees to be treated and divided by 16 to reduce to pounds. It is advis- 
able to obtain from 5 to 10 per cent more cyanid than the amount esti- 
mated, in order to avoid delays in case of underestimation. The 
cyanid, being put up in air-tight tin cases inclosed in stout wooden 
boxes, may be stored for months without deterioration. Excess 
cyanid can usually be disposed of without difficulty. 
SULPHURIC ACID. 
Sulphuric acid can be purchased in iron drums containing about 
1,500 pounds at about 1;;cents a pound. One drum of acid is required 
for about 4 cases of cyanid. The acid should be guaranteed 66° 
Baumé or 93 percent pure. It is advisable to have a sample tested 
with an acid hydrometer, an inexpensive instrument which can be 
obtained through any druggist. . Acid should not be stored for more 
than two or three weeks in the drum. Unless it is to be used at once 
the entire contents should be emptied into carboys, the mouths of 
which should be closed with wooden plugs, strips of burlap, and plaster 
of Paris. Empty carboys can be purchased for $1.50 or $1.75 each, 
and 9 are required to contain the contents of an acid drum. Only 
carboys in good condition should be used, since the container is made 
of thin glass and breaks easily if the bottom of the wooden case becomes 
weakened and fails to support the contents. Great care should be 
used in handling the acid. Probably the quickest and safest way of 
emptying acid from the large drum into carboys is a method which 
has been used on several occasions by the authors. The drum is 
mounted on two heavy planks resting on the ground and is arranged 
so that it can be rolled forward and backward easily. At one end of 
(Cir. 111] 
