92 BULLETIN 1H, U. S. DEPARTMENT OF AGRICULTURE. 
The length of a choker depends on the size of the timber; the 
range is from 15 to 30 feet or more. TThen chokers are made from 
new rope, 8 by 19 construction is generally used, the diameter, of the 
rope ranging from 1J to If inches. Most chokers are made of 1J- 
inch rope. Choker hooks for 1J to 1J inch line cost from $2.50 to 
$10. The type shown in figure 24 costs about $2.50 each. Sockets 
for 1J and 1J inch line cost about $2.25 each. On this basis a 30- 
foot lj-inch choker, with choker hook, costs about $23 and weighs 
about 70 pounds. 
The number of chokers in a set, or used in connection with one 
yarding engine, should vary with the character of the chance and 
the material from which they are made. For the purpose of this 
discussion eight chokers will be considered ample. It has been esti- 
mated that a 30-foot lj-inch choker, with sockets and hook, costs 
about $23. The chokers in a set are not of uniform length, however, 
and a 30-foot choker is longer than the average. For the purpose of 
estimating the fixed investment in chokers and choker hooks neces- 
sary for one yarding engine, an average length of 25 feet is assumed. 
On this basis the fixed investment amounts to about $165. 
Woods wafer sy stern. — Two methods of supplying water for log- 
ging engines are used. The more common one is to convey the water 
to the engines in pipes; the other, in tank cars. "Where water is 
plentiful it may be possible to supply all the engines through pipes 
by gravity at slight expense. Where the water is less plentiful it 
may be advisable to pump all the water used in the camp, in some 
cases by a central pumping station. Some operators haul the water 
in tank cars. At one three-side camp the water system, consisting 
of two steam pumps with boilers and 6 miles of pipe, cost $1,000. 
It would seem that a camp water system should never cost more than 
this. The selling price of black pipe is approximately as follows : 
Per 100 feet. 
|-inch pipe $4. 15 
lj-incli pipe 6. 10 
li-inch pipe 7. 30 
Miscellaneous equipment. — In addition to the equipment listed 
above, a rather large amount of small equipment is necessary, such 
as splicing tools, saws, axes, sledges, wedges, clamps, swamp hooks, 
oil cans, wrenches, shovels, hoes, etc. The fixed investment in such 
equipment amounts to about $250 per engine where one engine is 
operated ; about $200 where more than one engine is operated. These 
amounts are intended to take care of the equipment in use as well 
as the stock on hand. 
