mountains, and on the flanks of these mountains, to the northeast and to the southwest, lie various younger rocks which range in age from Carboniferous to very recent Tertiary, and are made up mostly of conglomerates, sandstones and shales, with some volcanic material. These rocks were formed subsequent to the ore deposition, and therefore do not contain metalliferous veins. They have been partly derived, however, from detritus worn from the gold-bearing belt during the long period that it has been exposed to erosion, and some of them contain gold derived from the more ancient rocks and concentrated in the same way as is the gold in the present river gravels. In one or two places it is certain that these conglomerates are really fossil placers, and this source of supply may eventually turn out to the very important.

In the younger rocks which overlie the goldbearing series there are beds of black, hard, glossy, very pure lignitic coal. An area of these coal-bearing strata lies very close to the goldbearing district, in the northern part of the region examined, and as the beds of coal are often of considerable thickness and the coal in some of them leaves very little ash and contains volatile

constituents in considerable amount, it is probable that the coal deposits will become an important factor in the development of the country.

There were probably 2000 miners in the Yukon district during the past season, the larger number of whom were actually engaged in washing gold. Probably 1500 of them were working in American territory, although the migration from one district to another is so rapid that one year the larger part of the population may be in American territory and the next year in British. As a rule, however, the miners prefer the American side, on account of the difference in mining laws. These miners, with few exceptions, were engaged in gulch digging. The high price of provisions and other necessaries raises the price of ordinary labor in the mines to $10 per day, and therefore no mine which pays less than this to each man working can be even temporarily handled. Yet in spite of these difficulties there were probably taken out of the Yukon district the past season, mostly from American territory, approximately $1,000,000 worth of gold.

An overland route should be surveyed and constructed to the interior of Alaska. All the best routes which can be suggested pass through

British territory, and the co-operation of the two governments would be mutually beneficial, since the gold belt lies partly in American and partly in British possessions. At the present time Mr. Spurr thinks that the best route lies from Juneau by way of the Chilkat Pass overland to the Yukon at the junction with the Pelly. This trail is the Dalton trail which has already been described, and it is said to open up a good grazing country and no great obstacles to overcome. The Chilkat Pass is considerably lower than the Chilkoot, over which the Geological Survey party of 1896 passed. If a wagon road, or even a good horse trail, could be built as indicated, the cost of provisions and other supplies would be greatly reduced, many gravels now useless could be profitably worked, and employment would be afforded for many men. the greater development of placer diggings would come the development of mines in the bed rock.

With

Besides the coal which has been alluded to there is abundant timber throughout the whole of the interior of Alaska, along the valleys of the Yukon. For four or five months in the summer the climate is hardly to be distinguished from that of the northern United States-Min

nesota or Montana, for example, and although the winters are very severe, the snowfall is not heavy. Work could be carried on underground throughout the whole of the year quite as well as in the higher mountains of Colorado.

The area hastily examined during the past season is but a portion of the great interior of Alaska. That gold occurs over a large extent of country has been determined, but the richness. of the various veins and lodes remains to be ascertained by actual mining operations. Gold is known to occur in the great unexplored regions south of the Yukon, because of its presence in the wash of the streams, and it is quite probable that the Yukon gold belt extends to the north and west; but this can be determined only by further exploration.

CHAPTER VI.

PLACER MINING AND HYDRAULICS.

There are four stages in the development of newly-discovered gold fields, such as those which have been brought to light in the Yukon Basin.

First come the men with crude outfits and few

resources, who, with pan and pick, gather the gold that lies near the surface, washing out the grosser earths and leaving the precious metal by itself. This is placer mining in its simple form.

After the gold lying on the surface and most readily at hand has been exhausted a little more complicated process is called into play. This is conducted by groups or associations of miners who use "long Toms" and cradles.

Hydraulic mining is the third stage. In hydraulics water is brought from a long distance and applied to the pay dirt at great pressure in order to separate the gold from the dross.

Last of all comes quartz mining, or tearing the gold by main force out of its beds in the rock beneath and separating it by means of stamps and pestles.

In the Yukon region the process has not yet passed the first stage, and so rich are the finds there and so difficult the importation of machinery and supplies that it may be years before the last stages will become available, although the never-satiated thirst for gold, combined with modern enterprise and ingenuity, is likely to make even the frozen rocks of Alaska amenable to modern appliances.