HOLMES] SOUTH MOUNTAIN RHYOI.ITE QUARRIES 75 



Fwriiace, Peuusylvaiiia, on a braiieli of the jMonocacy, 10 miles south- 

 west of Gettysburg-. Here the iiiouiitaius rise abrui>tly ami to great 

 heights from the narrow stream bed, and the rhyolite forms a large 

 part of the rocky mass. A cluster of flakes was observed on the road- 

 side some 2 miles above the railway crossing, and extensive aboriginal 

 quarries were soon found on the mountain side half a mile up the north- 

 ern slope. 



During the first visit only a lU'eliminary examination was jnade. 

 The ancient workings observeil cover several acres of the wooded moun- 

 tain side. The pitting is not pronouueed, although traces of disturb- 

 ance are readily recognized and the entire soil is tilled with broken 

 masses of the rock and the refuse of blade nuxkiug. Near the lower 

 margin of the (juarries a small patch had recently been cleared and 

 planted in peach trees. Here countless numbers of the partially 

 shaped pieces were to be seen, and in an hour I had my wagon loaded 

 with turtlebacks, broken blades, and luunmerstones. The rock tends 

 to break in flatfish forms, and the rejects indicate that the blades made 

 here averaged long and thin as compared with the shapes made from 

 the compact bowlders of the tidewater region. 



As in all the quarries so far examined, blade making was, so far as 

 the refuse indicates, the almost exclusive work of the shops. Plate 

 XXVIII is devoted to the illustration of specimens of successive grades 

 of development, from the mass of raw material reduced to convenient 

 size for beginning shaping operations to the long slender blades almost 

 as fully developed or advanced as are the blades found in the caches 

 and on the village-sites of the lowland. 



No evidence was found of attempts at specialization of form, and there 

 is not the least doubt that finishing operations were conducted subse- 

 quent to transportation to the villages in the valleys. Shops where 

 many small flakes were found contained fragments of unspecialized 

 blades only. The haramerstones were not numerous, and were as a 

 rule rather unsymnietric ghibular masses of greenishgiay eruptive 

 rock — ]ii()bably a diabase. 



These and probably other quarries of South mountain were the 

 centers i'rom which the natives distributed rhyolite over a vast area 

 including 20,000 square miles or more of the Chesapeake-Potomac 

 region. The quarry examined is 75 miles northwest of Washington, 

 and was readily accessible to the inhabitants of Potomac and Patuxent 

 rivers. The amount of material transported was very great, and the 

 industry must have been a most important one, frequent journeys to 

 the mountains of Penusylv.ania being a necessary feature. 



By a study of the range of quarry elaboration it is readily deter- 

 mined that the chief product was a blade corresponding to the prod- 

 ucts of other (piarries, and differing only as a result of the difference 

 in material. It has already been mentioned that multitudes of speci- 

 mens derived from this or other similar quarries in the mountains are 



