1824 REPORT OP THE CHIEF OF ENGINEERS. 



THE NEEDLE DISTRICT 



lies within the Needle Mountains, at the headwaters of the Florida, and the Vallecito, 

 or West Fork of the Rio Los Pinos, their western slopes being drained by waters of the 

 Animas. This section had been entirely unexplored by prospectors up to within the 

 last season, not from any lack of desire to enter it, but from the impossibility of ac- 

 complishing it, the mountains being wholly inaccessible. 



The only trail in the entire region, leading up the Vallecito, was cut early in Sep- 

 tember by our party in company with a number of prospectors and mining men. In 

 meandering the headwaters of this stream there were everywhere indications of valu- 

 able metalliferous deposits. Rich float was observed along the beds of the water- 

 courses, and wide veins of mineral deposits could be distinctly traced and followed 

 with the naked eye upon the mountain -sides. The similarity to Cunningham Gulch 

 was very striking; the veins in their general course lying northwest and southeast, in 

 the same direction as that of the great mineral belt in the vicinity of Silverton. 



The prospectors reported an abundance of rich lodes, mainly of silver, with indica- 

 tions of gold. The surface-outcropping, or " blossom rock," made the search for lodes 

 not only an easy task, but also very successful. 



The most promising lodes earliest discovered were the Dolly Varden, Clipper, Engineer, 

 Germania, Iron Rod, and Columbia, none of them being developed more than the 10- 

 foot assessment required. The specimens seen, giving line assays, were of argentifer- 

 ous galena, chiefly of high grade, with gray copper and sulphurets. The richest lode 

 of the district, as we afterwards learned, was one which assayed several thousand dol- 

 lars, and was discovered in October by one of the early prospectors, known throughout 

 the camp as " Dirty Jim." 



While at the head of one of the streams, float of decomposed quartz was observed sim- 

 ilar to the rock of the Little Annie at the Summit. Being followed up and its origin 

 found, although it was left unstaked, the temptation to locate was almost irresistible. 

 We learned later, that after our departure and the existence of a trail was known, a 

 stream of prospectors poured up the Vallecito during the two months intervening till 

 the close of season, and that numbers of rich u strikes" had been made. This will un- 

 ci mbtedly become, when properly developed, a most valuable district ; coal d( posits 

 abound on the Florida, close to the Los Finos, and an agricultural section is not far 

 distant. 



THE EUREKA DISTRICT, 



adjoining the Animas upon the north, is small in extent, hut rich in lodes, and lies 

 along the Animas River, from the dividing line near Howardsville to the divide be- 

 tween the Animas and Uncompahgre Rivers. The most valuable mining properties are 

 found in Eureka, Maggie, and Minnie Gulches. 



The towns of the district are Eureka, at the mouth of that gulch and about 9 miles 

 from Silverton, and Animas Forks, located at the junction of the two upper branches 

 of the river, 4 miles farther up ; both of these, however, should be properly known as 

 mining camps. 



The principal lodes are the Tidal Wave, McKinnie, Crispin, Sunnyside, Yellow Jacket, 

 Golden Fleece, Venus, Emma Dean, American, North Pole, Jackson, Grand Central, 

 Big Giant, Little Abbie, Belcher, Chieftain, Boomerang, Silver Wing, Lily, Golden 

 Eagle, and Great Eastern. 



The ores are in general argentiferous galena of high grade, gray copper accompany- 

 ing ; in Bums' Gulch specimens of the Lily and Golden Eagle lodes contained brittle 

 silver in considerable quantities, while in Eureka arsenical ores are found. On Jones' 

 Mountain, not far from this gulch, the Silver Wing, one of the finest mines of the dis- 

 trict, contains seven lodes so situated that they will be readily worked by a single tun- 

 nel. The owners propose erecting here, during the season of 1878, smelting- works for 

 their own ore. 



Selected ore of the Boomerang gave occasional mill runs of $475. 



The Eureka is the most x^romising gulch in the district, where more work has been 

 done than in any other, although its mines are in all stages of development. The 

 Tegner, Avith an 80-foot tunnel, a vein of about 10 feet, with a pay streak of nearly 3, 

 gave mill runs of 125 ounces of silver ; the Emma Dean, with a 50-foot tunnel, a crevice 

 of 20 feet, and a pay streak of 3, returned a mill run of 168 ounces ; and the Crispin, 

 also in Eureka Gulch, with a vein of 9 feet, and a pay streak of about 3, gave a value 

 of 160 ounces. 



The facilities for reducing ore have not been equal to the supply, and are mainly at 

 Animas Forks. Here are located the smelters of the Dakota and San Juan Mining 

 Company and the San Juan Smelting Company. The former possesses the usual 

 magnificent water-power, of which an idea may here be formed from the fact that the 

 town lies at the edge of timber line and on the mountain slope, down which the fall 

 of water is the greatest; beyond and down the gulch to the south the descent is 

 much less, although the average to Howardsville, 8 miles distant, is over 200 feet 



