188 GKAVEL AND PLACER MINING IN ALASKA. [bull. 263. 
The location of operating- levers, controllers, and switches is still a 
mooted question. Some operators prefer them on the lower deck 
close to the driving machinery; others in the pilot house, which is 
located near the forward end of the upper deck. In some installations 
they are placed in a pilot house just aft of the upper tumbler. With 
the first arrangement the winch man is among the driving machinery 
and can watch it, but unless he leaves his station he sees little of any- 
thing else and gets a poor view of the whole length of buckets. With 
the second arrangement the winch man can see the buckets better, all 
bowlines, but little else. With the third arrangement the winch man 
sees the buckets, the lines at bow and stern, the hopper, the screen, 
and enough of the gold-saving apparatus to know whether the riffles 
are clear, and with the aid of mirrors can also see the stacker and tail 
sluices. The objection to this arrangement and, in a measure, also to 
the second is that the winch man is isolated and therefore inaccessible 
(see PI. XXXV, B, p. 184). The type of dredge and height of upper 
tumbler should determine the position of the operating levers, con- 
trollers, and the switches, but in general it would appear that the 
advantage would lie with a location behind the upper tumbler. 
Loss of time has always been a serious factor in the use of gold 
dredges. The first installed in the United States operated less than 
50 per cent of the time. This was due to several causes, but princi- 
pally to the time consumed in making repairs and renewals and the 
difficulties brought about by the faulty arrangements for disposition 
of tailings. Minor causes, such as lack of cranes and derricks, can be 
overlooked, being unimportant by comparison. The writer, however, 
has seen the removal of troublesome stumps consume hours when, 
almost without exaggeration, it may be said that minutes should have 
sufficed for this purpose. It is noteworthy that many operations are 
hampered by lack of a sufficient number of lights for doing night 
work on or near the dredges. 
All dredges should be equipped with devices for hoisting and mov- 
ing the driving, screening, and pumping machinery, but these are now 
often lacking. The belting, both for stacking and driving, has caused 
much loss of time — a result due both to the poor quality of belts and 
to the attempt to make belts do work for which the}^ were not 
intended. Friction clutches, hoppers, and screens of bad design and 
inaccessibility of parts of equipment have also brought about a serious 
loss of time. This is specially true of renewals of such pans as baffle 
plates of hoppers and perforated sheets of screens. 
Cleaning up also consumes much time, and any arrangement that 
will permit continuous running during clean-ups of riffles charged 
with quicksilver will be of great value. Of late some managers have 
employed rather large crews to minimize lost time, though many 
dredges are still operated with but two men per shift. 
