2^^ The \\ est A^nciican Siie7itist. 



The nomenclature of this hastily prepared article may be some- 

 what mixea, as 1 have not the recent A. O. U. Check List, or any 

 other book by me for reference. 



Nov. 20, 1887. L. Belding, 



CALIFORNIA ROCK SALT. 



The regular meeting of the San Francisco Microscopical Society, 

 November 9th, 1887, was well attended ; President Ferrer in the 

 chair, and C. P. Bates, Secretary, pto tern. Doctor Douglas 

 Montgomery and Doctor Kahn of San Francisco, were elected 

 regular members. 



A sample of Mono lake water was handed in by Dr. Mouser, 

 and was referred to Mr. Paysant for the determination of crusta- 

 ceans living in it. 



The paper of the evening was by Mr. Henry G. Hanks of San 

 Francisco, concerning California rocK salt, as follows: 



Some months ago I received some fine specimens of rock salt 

 from Mr. J. S. Cook of San Bernardino County, which I found 

 very interesting, and at the same time I was impressed with the 

 importance of such salt to our State and to the Pacific Coast. 

 But press of other business caused me to lay the matter aside for 

 future consideration. Lately my attention has again been called 

 to this very interesting subject, and I have discovered certain 

 peculiarities in the mineral that I trust will be as interesting to the 

 members of this society as they have proved to me. 



Like the very best quality of rock salt, this mineral occurs in 

 blocks of the utmost transparency. It is quite easy to read print- 

 ing through a cube several inches in thickness. Some pieces are 

 as clear, colorless and free from mechanical impurities as ice from 

 distilled water, frozen in a vessel of porcelain. Others contain 

 some foreign matter which does not enter into the composition of 

 the salt. When dissolved and filtered the solution is perfectly 

 colorless, and on applying the usual chemical tests, without ob- 

 serving sufficient care to detect minute traces, the salt is found to 

 be almost absolutely pure. The fact that in a somewhat moist at- 

 mosphere it does not deliquesce is an additional proof of its chem- 

 ical purity. 



Some pieces transparent and colorless, melt at a red heat on 

 platinum foil without decrepitation to a transparent and also color- 

 less fluid, which retains its transparency when cooled. 



Other specimens show faintly opalescent lines meeting each 

 other at right angles. If such a specimen is held at a certain an- 

 gle in the sunlight, a multitude of reflecting surfaces like imbed- 

 ded spangles may be seen which glimmer something like aventu- 

 rine, or glow like a sun-stone. It may also be seen that while the 

 faint lines meet at right angles, a dividing line forms a miter like 

 the corner of a door panel. Such a specimen, when heated to- 



