96 JOURNAL OF THE [January, 



glass. Among these were projecting eye-pieces, for use with the micro-camera 

 in photography. Comparisons were also made between the Zeiss ordinary eye- 

 piece and the " compensating eye-piece." 



The Society received donations of material intrinsically valuable, and highly 

 prized because of its associations. " Moeller's typen platte" and "probe 

 platte," a number of valuable photomicrographs, and a large number of slides, 

 part of the collection of the late Prof. W. Ashburner, were donated by Mrs. 

 Ashburner, through Mr. Norris. Mr. Norris also donated a number of slides, 

 and prepared diatomaceous material. 



Mr. Norris exhibited a slide, mounted by Bourgoyne, of Paris, which con- 

 tained 215 distinct varieties of diatoms from the Santa Monica earth, all 

 arranged in beautiful form. 



Meeting of November 9. — President Ferrer in the chair. Dr. Douglas 

 Montgomery and Dr. Kahn, of San Francisco, were elected regular members. 



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

 referred to Mr. Payzant for the determination of its contained crustaceans. 



Mr. Henry G. Hanks read a paper on Rock Salt, found at San Bernardino 

 County, California. This salt occurs in blocks, usually of such transparency that 

 print can easily be read through cubes of it which may be several inches thick. 

 Some specimens exhibit faint lines and spangles which are the angles and sur- 

 faces of box-like cavities, probably containing gas or atmospheric air, which 

 fact causes these specimens to explode violently when heated. Mr. Hanks 

 illustrated his paper with specimens under the microscope. 



William Irelan, Jr. , State Mineralogist, donated to the Society two specimens 

 of diatomaceous earth, one from Dos Pueblos Creek, Santa Barbara County, 

 and the other from Shasta County. These specimens were referred to Mr. 

 Riedy and Dr. Riehl for examination and report. 



Brooklyn Microscopical Society. 



Meeting of November 21, 1887. — The regular meeting was held — 

 twenty-nine persons being present — at the new Laboratory and Lecture Room 

 of the Packer Institute, at the invitation of Prof. W. Le Conte Stevens. 



On request of the members Prof. Stevens explained the improvements in the 

 Lecture Room, made under his supervision, and the members were then con- 

 ducted through the Laboratory. 



Dr. J. H. Hunt then took the chair, in the absence of the President, G. D. 

 Hiscox, and the routine business of the Society was transacted. 



The Society was then entertained by a lantern'exhibition, prepared by Prof. 

 Stevens, in which, among numbers of beautiful objects, there were shown by 

 polarized light various rock-sections, chemical crystals, stained glass, selenite 

 films in many designs, including geometrical patterns, and many uniaxial and 

 biaxial crystals. 



Meeting of December 5. — A regular meeting was held for the first time 

 at the new permanent home of the Society in the Pratt Institute — Ryerson 

 Street, near Wiiloughby Ave., Brooklyn — twenty-three persons being present. 



Objects exhibited : — 



Fern-leaf Gold crystals ; by Dr. A. J. Watts. 



Crystals of native Gold ; by E. A. Chapman. 



Crustaceans and specimens of Pond-life ; by C. H. Taylor. 



Pigeon-post Film, of the siege of Paris, and a Hydrazoan, Eucratia chilata : 

 by H. W. Calef. 



Cancerous growth, Carcmoma ; by H. A, Tucker, Jr. 



Lozenge-shaped crystals of Asparagine ; by Geo. B. Scott. 



Slides of mineral substances — Chromium, Silicon, Boron, Cadmium, &c. ; by 

 Geo. M. Mather. 



Various slides of native Copper, and cabinet specimens of the same ; by Dr. 

 J. H. Hunt. 



