purington.] SLUICES AND GOLD-SAVING APPLIANCES. 1«H 
is at hand. From 30 to 60 miner's inches" of water are used. Opera 
tions of this kind, where from three to twenty men shoved in, are to 
be found on all the gold-hearing- creeks exploited in Alaska, though 
in the Klondike they have been largely supplemented by methods 
employing less hand labor. As none but rich gravel can be so worked, 
exigency permits a loss of fine gold. It is rare that placer miners will 
admit that they are losing gold, but it is safe to estimate that in the 
interior, where two to five boxes are in use for saving, and where 
drop-oil's are not used, or are only such as are caused by the telescope 
connection of the boxes, from 10 to 20 per cent of the gold lifted into 
the boxes is allowed to return to the creek bed. 
It would seem that heavy losses must occur in connection with the 
sluicing of the winter dumps taken out in drifting operations. The 
strings of sluice boxes are erected at as small an elevation as possible, 
in order that the greater proportion of the material will not have 
to be rehandled when the spring sluicing is done. PI. XXXVI, A, 
shows one method of dumping, in the winter, over previously erected 
sluices. Boards are laid over the sluices, and when sluicing is resumed 
the water is turned through the sluice, and, beginning at the lower 
end, the boards are successively removed. As much of the gravel as 
possible is caved in, sometimes with the assistance of a nozzle, and 
the remainder is shoveled, Avheeled to, and dumped into the sluice. 
Small bunkers or hoppers are sometimes built over the sluices, but no 
hoppers of large capacity, like those in use in Plumas County, Cal., 
were seen in the north. On Anvil Creek, in Seward Peninsula, a 
large winter dump was handled in this way, with the exception that 
those portions which could not be caved to the sluice were conveyed 
to it and dumped in by means of horse scrapers. Though loss of gold 
may be permissible in primitive operations of small capacity, it should 
become proportionally less when larger mechanical installations are 
made and the capacity of the plant is increased. 
One of the early difficulties which the miner in the interior encoun- 
tered was the presence of sticky clay and mud in the rich pay dirt. 
The difficulty was partly overcome by the introduction of the mud 
box, or puddling box, which was set in the middle or at the upper 
end of the string. Into this the men shoveled, or a bucket or car 
dumped. PI. XXXVII, A (p. 194), shows the form of the mud box 
used in the Klondike, and fig. 40 shows its position in the line of 
boxes. Its grade is generally made steeper than that of the rest of 
the string; 12 inches is common. The services of an extra man as 
stirrer, who also forks out the large stones, are required. 
Where men shovel into boxes the mud box is used merely as a 
wide part of the sluice. In larger plants, where buckets, cars, or 
a The term miner's inch used in this paper signifies an amount of water equivalent t<> 1J cubic feet 
per minute. 
