392 SUMMARY OF CURRENT RESEARCHES RELATING TO 
binocular telescope, and an unexampled collection of simple Microscopes 
in gold or silver engraved cases. Dr. H. Van Heurck, of Brussels, one 
of the most able and enthusiastic microscopists living, has also a fine 
selection of old instruments; but both of them, like Mr. Crisp, were 
unwilling to allow their treasures to be subjected to the dangers of a 
long journey. The Society will therefore be compelled to fall back on 
the collection in the Army Medical Museum at Washington, which, it is 
hoped, the Government authorities will bring here for exhibition. 
The exhibit of the Society ought to be of a good deal of interest, 
for in some senses it may be said that microscopy has reached its acme. 
Prof. Abbe says that it is not probable that any glass will be discovered 
of higher refractive index than that known, and without that it is not 
possible to construct lenses of much higher power or angle than at 
present. Our present objectives, then, are nearly perfected, unless 
future investigations show our theory of light to be erroneous. In 
regard to Microscope stands, there are a large number of forms for dif- 
ferent purposes, many very attractive. Klonne and Muller, of Berlin, 
manufacture one of the Zeiss form wholly of aluminium, except the foot. 
Those who will exhibit, so far as they have already consented, are 
Baker, Swift, Crouch, Beck and Beck, and Powell of London, Klonne 
and Muller of Berlin, Zeiss of Jena, Hartnack of Potsdam, Reichert of 
Vienna, and probably Nachet of Paris and Leitz of Wetzlar. 
One of the pleasant features of the exhibit will be that, by express 
permission of the manufacturers, the Committee of the Society will be 
allowed to show the various stands and objectives at the meeting of the 
Society or at such times and places as may be agreed on, so that all 
microscopists will have an opportunity of seeing the best foreign work, 
and comparing it with that done in this country. The domestic manu- 
facturers will not be behind in their display, and they have already 
taken the necessary steps to be seen. Dr. E. Cutter, of New York City, 
has consented to allow his famous Tolies 1/75 to be exhibited. The 
space assigned to the Society by Prof. Peabody, the chief of the depart- 
ment of Liberal Arts, is in the south gallery of the Liberal Arts Building, 
next to the astronomical and photographic exhibits, and close to the 
commercial displays of Bausch and Lomb, Queen and Co., Zeiss and 
others, and is in a very advantageous part of the building.” 
B. Technique. 1 ' 
Cl) Collecting: Objects, including' Culture Processes. 
Apparatus for Cultures in Vacuo.f — In the course of his researches 
on the ginger-beer plant Prof. H. M. Ward found it necessary to culti- 
vate in vacuo, and with the aid of Prof. McLeod devised the following 
apparatus a a', glass tubing attached to mercury pump beyond x ; b, 
bulb for condensed vapour ; w and w', cotton-wool plugs, the former in a , 
* This subdivision contains (1) Collecting Objects, including Culture Pro- 
cesses ; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes ; 
(4) Staining and Injecting ; (5) Mounting, including slides, preservative fluids, &c. ; 
(6) Miscellaneous. 
t Phil. Trans., vol. 183 (1802) pp. 125-97 ; figs. 49-51 by permission of the 
Royal Society. 
