156 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



Professor 13. Silliman has described an interesting and rare 

 occurrence of gold interspersed in massive scheelite from 

 Charity Mine, Warren's, Idaho Territory; and also another 

 similar case from the Golden Queen Mine, Lake County, Col., 

 where the gold appears in minute crystalline granules in the 

 scheelite. 



Mr. Samuel L. Penfield has given an analysis of the triphy- 

 lite from Grafton, N. H., which serves to establish the correct 

 formula of the mineral. 



Professor A. II. Chester has shown that the so-called pega- 

 nite of Arkansas is identical with the mineral called varis- 

 cite by Breithaupt, and callainite by Damour. He has also 

 described a remarkable fibrous variety of sepiolite from Utah, 

 some of which is colored bright green by oxide of copper. 



Dr. Koenig has described the occurrence of the rare rain- 

 erals astrophyllite and arfvedsonite from El Paso County, 

 Col., and has given analyses of both, as also of the zircon 

 associated with them. He has also identified the new min- 

 eral strengite (see beyond) at Rockbridge, Va., and has pub- 

 lished the results of a crystallographical and chemical exam- 

 ination of it. He has also given the name protovermiculite 

 (see beyond) to a hydrated mica. 



Professor G. C. Broadhead has described remarkable crys- 

 tals of barite from the Last Chance Mine, Morgan County, 

 Mo., and also the occurrence of gothite in limestone concre- 

 tions from Adair County, Mo. 



Garnets of the variety melanite have been found associated 

 in an interesting way with magnetite, apatite, and altered 

 pyroxene on the surfaces of the columnar trap of East Rock, 

 New Haven, Conn. ; and also the variety of garnet called 

 topazolite, having a complex crystalline form, at the junction 

 of the trap and sandstone of Mill Rock, New Haven. 



Professor H. Carrington Bolton has made an extended ex- 

 amination of the effect of organic acids upon a large number 

 of different minerals. The results are varied and interest- 

 ing, and suggestions are made from them in regard to the 

 application of some of the acids in the determination of min- 

 erals. Mr. J. II. Caswell has added to Professor Bolton's 

 paper a description of the microscopic crystals produced in 

 some of the reactions. 



