I 
p.iuN.rroN.] HYDRAULIC MINTNU. 103 
use of the ingenious device entails a new set of difficulties with which 
his previous experience in hydraulic mining will hardly have fitted 
him to deal. An unfortunate instance was seen in one of the remote 
districts of Alaska, where a hydraulic elevator of 5 tons weight had 
been imported at a cost of nearly $2,000 and was found useless because 
insufficient water to operate it was obtainable, although a ditch and 
flume line had been constructed at a cost of $15,000. The elevator 
lay on the bank, and a makeshift had been improvised from a piece of 
sheet-steel pipe and a fireman's brass nozzle. 
That hydraulic operations are and have been successfully prosecuted 
in Alaska is not to be denied. The cautionary remarks which have 
been made will serve as a reminder, however, that the moving of large 
bodies of gravel by water under natural head is not always as cheaply 
accomplished as a casual inspection of such operations would induce 
one to believe. In any event, a hydraulic installation, under condi- 
tions where the cost of leading water runs into the thousands of dollars 
per mile, should not be undertaken until due consideration as to the 
possibility of using other methods has been given. 
DITCHES, FLUMES, AND RESERVOIRS 
In table 8 an attempt has been made to show in concise form the prin- 
cipal facts regarding the construction of water conduits in Alaska and 
the North. So great was the extent of territory covered that oppor- 
tune for measurements and calculations was only occasional. The 
statements of operators were generally accepted; they were rejected 
only when they were palpably misleading. When not otherwise indi- 
cated, the data shown were supplied by the operators. When the data 
Avere based on subsequent estimates, the figures are starred. 
It can not be too strongly stated that the tables in this report are 
based on statements of operators and are not the result of detailed 
investigation of properties. The collection of data for this report 
necessitated the covering of a vast extent of territory in four months 1 
time. The data are as complete and as nearly accurate as the cir- 
cumstances allowed. Estimates based on the cost of water conduits 
as given below, and the amount of water available, should take into 
consideration the degree of authority which attached to the compilation. 
