22 GRAVEL AND PLACER MINING IN ALASKA. [bull. 263 
Per cent of gold caught before and after elevator. 
Frequency, time, and cost of moving elevator. 
Difficulties encountered in its use. 
Form 3. — Dredging. 
Make and cost of dredge. 
Estimated and actual capacity of dredge in cubic yards per twenty-four hours. 
Is dredge in a river or in self-made pond? 
Depth to which buckets dig, and height of bank above water level. 
Where was hull constructed and of what material? 
Feet of lumber in hull and cost of hull. 
Dimensions and draft of hull, loaded. 
Weight of machinery. 
Power used, nature, amount, cost per day. 
Height, size, method of bracing, and inclination of gauntrees. 
Size, weight, position, and description of spuds, if used. 
Size, number, position, and use of winch drums. 
Position of lever house. 
Size, number, and length of cables. 
Does dredge dig on spud or head line? 
Length, width, weight, material, of digging ladder. 
Material and weight of tumblers. 
Number, capacity, arrangement, weight, shape, and cost of buckets. 
Material, life, and cost of bucket lips, pins, and bushings. 
Are teeth used on any buckets? 
How far in front of bow will buckets dig? 
What size of stones are handled? 
Do buckets clean bed rock? 
Describe save-all, if used. 
Is nozzle used for cleaning buckets? 
Is trommel or shaking screen used? Preference. 
Dimensions and life of trommel; size holes. 
Is side chute used for large stones? Describe grizzly. 
Is sluice box with auxiliary float used? If so, describe. 
Is stacking ladder used? Length, how driven, steel-link belt, or rubber belt, width. 
Height and distance from stern stacked. 
Life, efficiency, and cost of stacker belt. 
Treatment of fines, area, grade, and description of tables; kind of riffles most suc- 
cessful, amount of quicksilver used. 
Is sand pump used? How often? 
Clean up, how often? State method used and time consumed. 
Size, make, and cost of pump used for supplying sluice water; height of lift. 
Distribution of power; how much to each operation. 
Size and capacity of boilers and engines or dynamos used; describe connections 
pulleys, and clutches. 
Special difficulties owing to northern conditions. 
Most frequent breakages. 
What kind of ground does dredge work best in? 
What kind of ground does dredge have most difficulty in? 
If in pond, is water pumped in? How much? From what source? 
Cost per cubic yard of digging and washing gravel. 
