130 BULLETIN til, U. S. DEPARTMENT OF AGEICULTUEE. 
Equipment. — The kind, size, length, and selling price of the lines, 
also the fixed investment in the lines, are discussed under " Cost." 
The number and type of blocks used with this system is indicated 
in Figures 37, 38, and 39. A complete set of these blocks f. o. b. 
Portland or Seattle costs from $1,500 to $2,000 and weighs from 
18,000- to 22,000 pounds. 
The type of carriage used is shown in Figure 40. These carriages 
f. o, b. Portland or Seattle cost from $100 to $500 and weigh from 
1,000 to 1.200 pounds. 
Output. — In general, the output with this system ranges from 
50.000 to 100.000 feet per day. For short periods it may be greater 
or less than this. One skidder, where the maximum yarding distance 
was 1,000 feet, yarded 1,000,000 feet in five days. On steep mountain 
sides, where the yarding distance ranges from 2,000 to 2,500 feet, the 
output may range from 50,000 to 75,000 feet. 
The average output per skidder per skidding day, on the basis of 
a month's time, in a camp where five skidders were used, was 80,000 
feet. The largest output of any of these skidders in a day during 
this period was 182,000 feet. In this camp, during the same month, 
four ground yarding engines were operated, the average output per 
engine per yarding day amounting to 10,000 feet. The maximum 
yarding distance in the case of the skidders was 1,200 feet ; in the 
case of the ground yarding engines, 700 feet. The logs yarded with 
both systems averaged about 800 feet in volume. Another operator, 
working a skidder and a ground yarding engine in chances of the 
same character, was getting about 75,000 feet per day with the 
skidder and about 40,000 feet with the ground engine. The timber 
was small, second growth, and the ground practically level. Still 
another operator was getting an output of about 90,000 feet per day 
with a skidder. The maximum yarding distance was 1,200 feet, the 
ground was practically level, and the logs averaged about 1,000 feet 
in volume. One operator who used the overhead skidder discussed 
the output as follows : 
As to the output, we are not in a position to say what the system will do 
in a good chance. We have used it in very rough, steep ground and in small 
timber. From May 1 to May 1 we worked 227^ days, being shut down during 
the month of July and having the usual Christmas shut down, and put in 
9,164,000 feet, or a daily average of a little over 40,000 feet. This is not a large 
average, but, owing to the conditions, think it is better than Ave could have 
done with the ground yarding system. Our largest day was 84,000 feet and our 
best monthly average was 53.000 feet per day. In these averages the time 
consumed in moving has been counted in as working days. 
Cost. — Nothing further than a general discussion of the elements 
of cost will be attempted. The factor of output, which has already 
been referred to, is of major importance. While the size of the crew 
