purington] SLUICES AND GOLD-SAVING APPLIANCES. 193 
plant, where the gravel is dumped into the mud box by means of the 
cable tram and self-dumping- carrier, like that illustrated in PI. 
XXXVII, A. The capacity is 175 cubic yards in twenty-four hours, 
and the cost is approximately $1.50 per yard. After it is hoisted from 
the shaft the material is elevated to a height of 25 feet above the sur- 
face of the ground. Water is pumped to this height for sluicing. 
The sluice consists of a mud box 16 feet long and 30 inches wide, on 
a 12-inch grade, tapering to the 14-inch sluice boxes which follow. 
There are eight of these, set on grade of 10 inches to 12 feet, fur- 
nished with pole riffles, which last three weeks only and cost $3 per 
box length to renew. The man forking in the mud box costs $6.50 a 
day of ten hours. At this plant the gold is in part very finely divided, 
and it is impossible to believe that the sluice in use is operating with 
economy. 
Proof of the losses now going on in the Klondike was seen on a neigh- 
boring creek. At a plant somewhat larger than the one above described, 
where 240 cubic yards a day were handled at a cost of $1 a cubic yard, 
a small undercurrent had been installed, at the end of ten 16-inch 
boxes, 12-inch grade, pole riffles. The undercurrent was fed through 
a small iron grizzly, and consisted merely of one 16-inch sluice box, 
12 feet in length, with a riffle of cocoa matting and expanded metal. 
It cost $20 to construct this device, which was saving an average of 5 
per cent of the product each day. A sample of the gold was taken, 
and although some of it is too fine for handling, such particles as 
could be weighed and counted gave a result of 280 colors to the cent, 
the gold being worth $15.60 per ounce. Gold of finely divided but 
never flaky character was seen in all the large producing creeks of the 
Klondike, and at the new Fairbanks district of Alaska. 
The plants above referred to represent the average capacity of the 
creek mines of the interior of Alaska, where the hoisting of material, 
and frequently the pumping of sluice water are necessary. It costs 
from $3,000 to $5,000 to rig up such plants, which are used for three 
seasons or longer. To install a washing plant in such a case as the 
above would add little to the first cost, and the additional expense 
would probably be justified by the results. 
Before entering on suggestions as to the use of washing plants, I 
wish to emphasize the fact that the methods of sluicing in use in 
Alaska, especially in the Birch Creek, Fortymile, and Fairbanks dis- 
tricts, and to a certain extent in Seward Peninsula, have been, and 
will continue to be, influenced by the Klondike developments. Though 
many of the methods developed in the Klondike are excellent and are 
worthy of imitation in any country where conditions are similar, at 
the same time the Alaskan miners should note the wrong principle of 
the primitive sluice box which has been continued there. The entire 
Bull, 263—05 13 
