PURINGTON.] 
OPEN-CUT MINING. 
55 
~ . Average fall 
Council district: In feet per mile. 
Ophir Creek 25 
Melsing Creek 50 
Solomon district: 
Solomon River 20 
Shovel Creek 90 
Average sluice-box grade 220 ( or 6 inches to 1 2 feet) . 
OPEN-CUT MINING. 
INTRODUCTION. 
Under this heading will be discussed the various methods of mining 
by which gravel is taken out of open cuts — either simple pick-and- 
shovel methods or methods involving the use of mechanical contriv- 
ances. Hydraulic methods will be considered in a later section. The 
simplest of the open-cut methods dominated throughout the province 
up to within a few years, to the practical exclusion of all others except 
winter drifting, which will be considered below. To-day probably 60 
per cent of the placer-mining operations in Alaska are confined to 
Fig. 5.— Klondike rocker. 
open-cut methods, and this investigation has brought the proof that, 
when combined with proper mechanical devices, these form often the 
most economical mode of exploitation. 
Open-cut methods can be conveniently grouped under various head- 
ings, but the underlying principle of excavating and transporting the 
material to the washing apparatus, either by hand labor or by some 
mechanical means, remains the same. It therein differs from hydraulic 
mining, where the gravel is moved by water under pressure. There 
are, of course, various intermediate processes, which will not require 
separate consideration. 
ROCKER AND LONG TOM. 
The simplest method of work which the miner adopts after he has 
passed the stage of panning is that of shoveling from the bank and 
washing the gravel in a rocker. The use of the rocker is too well 
known to need description. The form employed in the Klondike, 
where its use has been nearly discontinued in mining, is shown in 
