1885.] NEW YORK ACADEMY OF SCIENCES. 73 



upon a tliong, and used somewhat like a sling-shot; but the end 

 was broken in the drilling. 



Mr. Kunz also exhibited and remarked upon several plates of 

 mica found by Mr. Chas. Gavoille in a clay bank, twenty yards 

 from a swamp, in the "French quarter" of Digman township, 

 Pike Co., Penn. These plates measure thirteen by eight inches 

 (325 by 200 mm.), and are pierced with four perfectly round 

 holes, seven mm. in diameter. They are not over one-fourth 

 inch in thickness, and are the finest magnetited muscovite or 

 "picture mica," and evidently served very well the purpose of 

 " mirrors." The original locality of this mica is probably Penns- 

 bury, Cliester Co., Pa., and the quality is the finest of this 

 variety. 



Plates of mica have been found all through our coast States, 

 and even further west than Ohio. They are sometimes thirteen 

 inches long, ten inches wide, and half an inch thick. Col. C. 

 C. Jones, Jr., describes some specimens which he exhumed in 

 Southern mounds. They were about seven inches long and five 

 inches wide, and in shape were either parallelograms, squares, or 

 elongated hexagons. At each end was a triangular indentation. 



These "mirrors" are seldom drilled more than once, and 

 when, as is rarely found, there are four holes, it was probably to 

 prepare them for use as ornaments; perhaps to be worn upon the 

 breast. 



President Newberry said that mica had been found in 

 the mounds in Ohio. From a mound in the Cuyahoga Valley, 

 twenty miles south from Cleveland, at least a peck of mica was 

 found in one heap. It contained spangles of magnetite, and had 

 evidently been derived from the Alleghanies, Avhere mica was 

 very extensively mined by the ancient inhabitants of the country. 

 Dr. Julien visited some of these old mica mines, and described 

 them to the Academy. The mica of the mounds seems to have 

 been used for ornament, as pieces are occasionally found cut into 

 definite forms and pierced with holes for attachment. 



Galena is often found associated with mica in the mounds 

 of the Mississippi Valley, was probably valued for its brilli- 

 ancy, and may have been used as a personal ornament or decora- 

 tion of shrines, as it seems to have nev'.r been smelted. It is 



