GEOLOGICAL SURVEY OF THE, TERRITORIES. 211 



is done by means of steel drills worked by compressed air, tbe macbiue 

 for driving them being mounted on a car running on rails. A steam 

 engine outside compresses the air and forces it through pipes to the 

 machine in the interior. It is expected that a lode will be intersected 

 about one hundred feet further in. 



The Snoiodrift mine. — This mine is three quarters of a mile below the 

 Brown lode, on the same side of the creek, and is five hundred feet higher 

 up the mountain than the same. The ores are chiefly sulphuret, (silver 

 glance,) and galena. Very little iron or copper pyrites or zincblende is 

 met with. The vein is five feet in thickness, and the pay streak, (one- 

 half of which is said to be composed of silver glance,) six inches m 

 width. The cost of getting out five tons (including wages, «&c.) was 

 seventy dollars, and the ore averages one hundred ounces per ton. 



The Griffith lode. — This lode, like the Gregory, near Central City, is 

 the oldest as well as one of the richest in the vicinity of Georgetown. 

 It is situated in a high hill or mountain on the right bank of Clear 

 Creek. The shaft opening is about half way up this hill. The shaft is 

 one hundred and twenty-seven feet deep, from which a drift has been 

 struck fifty feet east, and ten feet west. The dip of the- vein is a trifle 

 south, though it is nearly vertical. The crevice averages perha]:)s four 

 to five feet, and its north wall-rock is a syenite, while the south wall 

 rock appears to be a weathered granite. Assays show values of from one 

 hundred to seven hundred ounces per ton. The ore will average per- 

 haps one hundred and fifty ounces per ton. The expectation was, when 

 the improvements in progress had been made, to take out fifty tons of ore 

 'per diem. Some little trouble was experienced from water in the early 

 spring, but not enough to hamper the efficient working of the mine. 



This comi)any owns twenty-five feet each side of the lode and three . 

 hundred on the lode each side of the discovery shaft.* The upper part 

 of the north wall-rock consists of a decomposed, yellowish coarse-grained 

 mixture of gneiss and quartz porphyry, but below it is a hard, compact 

 syenite. The south wall-rock appears to be, above, a reddish ferruginous 

 weathered granite, and, below, a white, compact quartz porphyry. 



The following is as accurate a list as could be obtained of the princi- 

 pal lodes worl5:ed at the present time in the vicinity of Georgetown : 

 Baker, (worked for three years;) Brown and Coin, Terrible, Lily, Men- 

 dota. Snowdrift, White, Elijah Hise, Wm. B. Astor, Cliff, Xew Boston, 

 B. Nuckles, Belmont, Continental, Equator, Gilpin, Griffith, Comet, 

 Magnet, Anglo-Saxon,-!- Young America, and Wall Street. 



There are seven mills and dressing works in the vicinity. 



From the Equator and Terrible the first-class ores are hand-dressed, 

 (from the former simply broken and boxed, from the latter crushed and 

 sacked,) and sent to the Eastfor further treatment. The lead is notpaid 

 for. I am informed that in the ]S"ew Boston mine there is in one place 

 fifteen feet of solid galena. The same authority states that a shaft was 

 sunk on the vein one hundred and seventy-five feet before it was dis- 

 covered that the crevice, instead of five, was fifteen feet in breadth. 



J. 0. Stuarfs mill. — This mill stands on the left bank of Clear Creek, 

 just below Georgetown, and is built for custom ores. The greater part 

 of the business of this mill is derived from the Equator and Terrible 

 second-class ores. The average amount of ore put through tlie mill is 

 about three tons a day, or one thousand tons a year. The process is 



* See Miniug Laws of Colorado. 



t In the Anglo-Saxon, I am informed that native silver liredomiiiates over all other 

 metals, hut the iiay streak is very narrow. 



