126 THE NORTHERN MICROSCOPIST. 

He fully described the Stand, and the description was well illustrated by a large 
drawing which he had prepared, and also by several smaller engravings, shewing 
the instrument in its various positions. 
Mr. Jas. Fleming called the attention of the members to a slide, in which he 
had been successful in mounting Volvox globator in glycerine jelly. 
Mr. J. L. W. Miles, by the aid of a coloured drawing which he had prepared, 
explained his theory of the building up of the tube case A/ehcerta ringens. 
Mr. H. P. Aylward exhibited and described Beck’s Ideal Microscope, with 
swinging substage and mirror. He also shewed a new Live Box which he had 
made at the suggestion of Mr. Burnett, F.R.M.S. Mr. Burnett briefly ex- 
plained the many advantages of the improved instrument. 
Mr. Stanley brought for distribution packets of various Mosses, and Mr. Miles 
distributed AZelicerta ringens. 
The usual display followed, and among the exhibits were the following ;— 
Ninsemartibre trom Gra wa. mrrenceotescrstreneas cae Mr. Alston. 
Poison gland s,or HOUSE: Spider vers. devs. say mere Mr. Chadwick. 
Mounts of rare Mosses gathered between Buxton } Mie "Saar 
and Maller’s ‘Dale. -:. 5: acseearscsac ier lveeerent ands SR ee ys 
Volvox globator mounted as a permanent object..Mr. Fleming. 
LECUCEHE AL FLMCEMS be tarcrptebioren SOR TAINRE OTS OSTA Mr. Miles. 
Symbiotes Equi and Symoboites spatheferus ......... Mr. Wolstenholme. 
Hermit Crab and Mymphon gracile .occccccccecseees Mr. Brauer. 
' Mr. George E. Davis exhibited Tolles’ 1/8th solid ocular and Gundlach’s one 
inch periscopic eye-piece. He also exhibited a first quality one-inch objective 
by Tolles, the performance of which over a scale of Morpho Menelaus was 
remarkable, while when used over the scales of Polymmatus argus, it showed 
that these objects were not in any true sense of the word tests for it. Over the 
larger scales of P. avgiolus the lines are clear and sharp with the 1/8th solid 
ocular combined with the use of Tolles’ amplifier, yielding thus an amplification 
of at least 1600 diameters. 
ROCHDALE MICROSCOPICAL CLUB.—At the monthly meeting, held 
on April 3rd, at the Club-room, 68, Yorkshire-street, Rochdale, Mr. J. Astin 
gave the first of a series of practical demonstrations on “ Microscopical Mlumin- 
ation.” He first shewed what was meant by the terms—direct light, oblique 
light, and dark-ground illumination. The first did not need any detailed 
explanation. With different instruments he then shewed various methods of 
obtaining and using oblique light—first, by means of the mirror inclined at a 
considerable angle to the axis of the mirror; secondly, by inclining the body of 
the instrument nearly to the horizontal, and using the bull’s-eye condenser; 
thirdly, by a combination of the two former methods, so as to obtain a true 
dark-ground illumination. He proceeded to shew more elaborate methods of 
obtaining the same results by means of the spot-lens, and also by a bull’s-eye 
condenser, with a round spot of black paper in the middle, placed under the 
stage, and between it and the mirror. To make the demonstration really 
practical, he then disarranged the various appliances, and the younger nembers 
of the club then essayed to arrange them again so as to obtain the same results. 
The following rare pond-life forms have been obtained by the members in 
this district:—ALG@: Batrachospermum moniliforme, Coleochate scutata. 
ANIMAL LIFE: JZelodinium Uberrinum, Synura Uvella, Floscularia cornuta. 
ROCHDALE AND WHITWORTH MICROSCOPICAL SOCIETY. — 
The usual monthly meeting of this Society was held on Thursday evening, 
April 13th. There being no special business and no paper, the meeting 
resolved itself into a conversazione, when some very interesting objects were 
exhibited by the members. 

