18 ON THE GOLD MINES OF CANADA, 



method, however, the cost of cutting away and excavating is so 

 trifling, that there is scarcely any bank of earth which will not 

 pay the expense of washing down, in order to reach the richer 

 deposits of gold beneath. 



" The acqueducts or canals for the raining districts of California 

 are seldom constructed by the gold workers themselves, but by 

 capitalists, who rent the water to the miners. The cost of one 

 of these canals, carrying the waters of a branch of the Yuba 

 River to Nevada County, was estimated at a million of dol- 

 lars ; and another one, thirty miles in length, running to the same 

 district, cost $500,000. The assessed value of these various canals 

 in 1857 was stated to be over four millions of dollars, of which 

 value one-half was in the single county of Eldorado. The Bear 

 River and Auburn Canal is sixty miles in length, three feet deep 

 and four feet wide at the top, and cost in all $1,600,000 ; not 

 withstanding which, the water-rents were so great that it is stated 

 to have paid a yearly dividend of twenty per cent, while other 

 similar canals paid from three, to five and six per cent., and even 

 more, monthly. The price of the water was fixed at so much the 

 inch, for each day of eight or ten hours. This price was at first 

 about three dollars, but by competition has now been greatly 

 reduced. 



" From these statements, it will be seen that the great riches 

 which have of late years been drawn from the gold mines of Cal- 

 ifornia, have not been obtained without the expenditure of large 

 amounts of money and engineering skill. This last is especially 

 exhibited in the construction of these great canals, and the appli- 

 cation of the hydraulic method to the washing of auriferous de- 

 posits, which were unavailable by the ordinary modes of work- 

 ing, on account of their distance from the water-courses, or by 

 reason of the small quantity of gold which they contain. 



" In order to judge of the applicability of this method of wash- 

 ing to our own auriferous deposits, a simple calculation based 

 upon the experiments at the Riviere du Loup will be of use. 

 It has been shown that the washing of the ground over an area of 

 one acre, and with an average depth of two feet, equal to 87,120 

 cubic feet, gave, in round numbers, about 5000 pennyweights of 

 gold, or one and thirty-eight hundredths grains to the cubic foot ; 

 which is equal to one and three-quarters grains of gold to the 

 bushel. Now, according to Mr. Blake, earth containing one forty 

 fourth part of this amount, or one twenty-fifth of a grain of gold, 



