58 PROCEEDINGS OF SOCIETIES. 
Mr. J. P. Moore presented the Society with two volumes of 
‘Spencer’s Biology,’ and Professor Ashburner stated that he had 
purchased for the Society, while Hast, one of Tolles’ jth immer- 
sion objectives, one each of Tolles’ solid one-half and one-quarter 
inch eye-pieces and a Wenham reflex illuminator, the latter of which 
was tested during the evening for oblique illumination while resolving 
some test diatoms, and it was satisfactorily proven that one of the 
greatest advantages of the accessory was its use with the ordinary 
thick stages, which preclude the obliquity of light necessary for tests 
with high powers. While speaking of this, President Ashburner 
stated that in his interview with Professor J. Edwards Smith, of 
Ashtabula, Ohio, he noted the fact that his stage was of extraordinary 
thinness, and was one of the apparent essentials when nothing but 
illumination from the mirror was used. The Society’s duplex +,th 
of Tolles’ was used, and the Society’s balsam Méller proof-plate, 
and Professor Smith showed Nos. 18, 19, and 20, clear and distinct 
within fifteen minutes, although he admitted that the Society’s glass 
was not equal to his. 
President Ashburner has proved an apt scholar in the manipu- 
lation of the objective, and from a subsequent interview with Mr. 
Tolles, and with the tenth overhauled and refitted, he is equal to the 
emergency, being able to show members of the Society the lines on 
18, 19, and 20, as plainly as the pickets on a fence. The new Tolles’ 
sixth also resolves in his hands the same tests without difficulty, on a 
balsam plate which is just what it represents to be. 
Mr. J. P. Moore made a further statement regarding the grape- 
vine fungus which he had examined and reported on at a previous 
meeting, to the effect that the same Erysiphe he had found since on 
the native vines. 
Mr. G. W. Barnes, of San Diego, sent a communication to the 
Society, accompanied with a bottle of sediment obtained from the 
water supplied to that city from the bed of the San Diego river, and 
desired a statement as to its characteristics microscopically. It was 
handed to Mr. Hanks, who promised a report at the next meeting. 
Dr. Wythe exhibited a photograph of Zentmayer’s new model, and 
during the evening Mr. Banks filled one of the revolving tables with 
instruments just from the Centennial Exposition. Among them was 
Crouch’s standard microscope, with new centering arrangement, which 
was most perfect ; one of Walmsley’s binocular stands, and a Holmes’ 
class stand. 
The regular meeting was held on Thee November 2, with 
Vice-President H. C. Hyde in the chair. 
Mr. H. G. Hanks donated a quantity of material for mounting in 
the way of Cinnabar crystals, showing double termination, from 
Sulphur Bank, Lake County, California. He also exhibited a speci- 
men of beautifully crystallized Polybasite, from Austin, Nevada, which 
silver mineral is rarely found so interesting. 
Referring to the sample of water handed to him at last meeting, 
Mr. Hanks presented a paper embodying the facts ascertained in his 
