156 TRANSACTIONS OF THE 



besides which much of the quicksilver was lost ; still, 

 however, under all these disadvantages, the quantity of 

 three and a half grains of gold was obtained from an 

 average of four pounds of ore, taken indiscriminately 

 from all parts of the vein, and in another experiment, 

 five grains of gold were obtained from four pounds of 

 pure milky white quartz, which had no appearance or 

 indication of containing any metal at all. 



It may, therefore, be fairly inferred that if the ex- 

 periments had been better and more accurately con- 

 ducted, and made on a larger scale, that each pound 

 weight of average ore would have yielded one grain of 

 gold, or at the rate of five pennyweights to the hundred 

 pounds weight of ore, which is much more than the 

 probable, or indeed possible cost of working the mines, 

 as we conceive that could in no case amount to so much 

 as one dollar upon the hundred pounds weight. 



In conclusion, we have to remark, that the water in 

 the rivulet is by no means sufficient in quantity to make 

 it available as a water power, or even to furnish suffi- 

 cient water for washing and dressing the ore that may 

 be raised ; consequently it will be necessary to make use 

 of animal or steam power for stamping and grinding the 

 ores, and that the water for washing the same must be 

 brought in artificial channels from the Rappahannock. 



We are, gentlemen, with great respect, 



Your obedient servants, 



ANDRES DEL RIO, 

 JOHN MILLINGTON. 



Philadelphia, Aug. 4. 1834. 



