158 Queries. 
399.—Dry Mounting.—I shall be very glad of any information 
as to the simplest and quickest method or methods of neatly and 
effectually preparing dry mounts for the microscope. I daresay 
this will bring a reply from some kind reader, who will smile at 
such an apparently simple request. That is the reader to whom I 
would specially appeal. There are many methods of “ putting- 
up” dry objects as there are of fixing in balsam, which latter 
process is simple enough to me, but was anything éw¢ simple when 
I first tackled the process. To balsam mounts I have so far con- 
fined myself, but my dry objects are accumulatiag, and I shall be 
much obliged to any “dry-mount friend” who will give me a 
“wrinkle ” or two. 
Does any reader know anything of the “rings with an internal 
flange at the top and an external flange at the bottom,” figured and 
described in the English Mechanic, 1,158, June 3, 1887, in an 
article entitled “A Quick Method of Mounting Dry Objects.” The 
paper in question originally appeared in the Scientific American,” 
and the mode of putting up dry objects for the cabinet as ex- 
plained by the writer (G. M. Hopkins) rather takes my fancy, if I 
knew where to procure the rings and the heating-tool. PYRG: 
400.— Abbe Microscope-Condenser.—Will some reader of the 
Linguirer, who has good experience of the “Abbe” condenser, 
kindly say whether it is all that Zeiss states it to be in his cata- 
logue? It is asserted that, with the combination of r-4o0 N.A., it 
will easily afford any and every modification of light of the most 
extreme obliquity for resolving the severest diatom tests with the 
highest-angle lenses, that it will give dark-ground illumination up 
to 600 diameters, and that the various results are cas¢y produced 
by merely changing and moving the different diaphragms supplied 
with it. Any information hereon will be acceptable. I should 
also like to know how it performs as an immersion condenser, and 
whether a good dark-ground with the polariscope is afforded by it. 
I have no doubt that more than one reader of the Enguirer will 
be able to furnish the required particulars, and that they will be 
very useful to readers generally, as they certainly will be to 
Bu Rae: 
401.—Poison of Bees, Wasps, ete.—What is the nature of the 
poison of these insects, and what are its chemical constituents ? 
ALS 
402. —Odontomes.—Will some one tell me the best medium in 
which to mount sections of odontomes and skins ? Z. M. 
403.—Card Specimens.—What is meant by “Card Speci- 
mens”? It is a term used in medical societies. B. W. 
404,—Soda-Lye.— What is soda-lye, how is it made, and where 
may it be procured ? X. 
