36 ALASKAN MINERAL RESOURCES IN 1904. [bull. 259. 
In the districts not visited the classes of deposits are as follows: 
Classes of deposits worked in districts not visited. 
Province. 
District. 
Class i.f placer worked. 
South Coast 
Porcupine 
Creek and bench placers. 
Do. 
CreeK placers. 
Do. 
1 
Nizina 
Chisna 
Sunrise 
interior 
Fortymile 
Creek and bench placers. 
Do. 
Rampart 
Seward Peninsula . . . 
Topkok (Nomedist. ) 
Port Clarence 
Fairhaven 
Creek, gravel-plain, and 
placers. 
Creek and bench placers. 
Do. 
Do. 
sea-beach 
Kougarok 
MINING METHODS AND CONDITIONS. 
The mining of placer gold in Alaska is carried on for the most part 
during June, July, August, and September. The gold-bearing gravel 
mined during the remainder of the year by winter drifting does not 
exceed 15 per cent of the total annual amount extracted. The gold can 
not be washed from this gravel until the cessation of winter conditions 
liberates the water in spring for sluicing purposes. The sluicing of 
the " winter dumps" takes place during the latter part of IVbry. 
Many of the methods of mining have been developed within the last 
ten years to suit the unusual conditions existing in the northern gold 
fields. Gravel miners from other parts of the world found that in 
Alaska much of their previous experience proved of no special benefit. 
On the other hand, men without previous experience in mining, but 
possessing ingenuity, have occasionally adopted devices which have 
proved efficient and adequate to meet the northern conditions. 
Methods which had been condemned or tried with ill success in other 
countries have given good results in Alaska, while the attempts to 
apply hydraulic or mechanical methods of established reputation else- 
where have frequently resulted in ignominious failure. 
Mining operations have been made difficult by the short available 
season, the lack of grade to the streams, poor water supply, poverty 
of timber resources, high cost of labor and transportation, concentra- 
tion of gold on and in the bed rock and comparatively great thickness 
of barren overburden, the frozen, or worse still, half-frozen condition 
of the gravel, lack of wagon roads, and inadequate mining and police 
