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CORRESPONDENCE. 
“ Using the |yh Binocularly.” 
To the Editor of the 1 Monthly Microscopical Journal.' 
Padnal Hall, Chadwell, Essex, Nov. 6, 1ST 2. 
Dear Sir, — Permit me to state that there is no foundation for the 
assertion contained in the letter by Mr. S. Smith, on page 247 of the 
last ‘Monthly Microscopical Journal,’ that I am engaged in perfecting 
a Binocular Microscope that could be used with a Afh. My instru- 
ment has always acted perfectly with that power giving a full field. 
With my own ith it acts also very well, simply because the object- 
glass is “ dumpy,” or, in other words, has a very short setting, so that 
the prism comes closer to the back lens. I believe that improvements 
enabling the Binocular to be used with the highest powers are quite 
possible. I have not, however, given any attention to the subject for 
some years past. 
Yours sincerely, 
F. H. Wenham. 
PROCEEDINGS OF SOCIETIES. 
Royal Microscopical Society. 
King’s College, November 6, 1872. 
Charles Brooke, Esq., F.R.S., Vice-President, in the chair. 
The minutes of the last meeting were read and confirmed. 
A list of donations was read, and a vote of thanks passed to the 
respective donors. 
Mr. Ingpen read a paper on “ A Proposal for a Standard of Com- 
parison of Magnifying Powers of Compound Microscopes.” 
Mr. Hogg said he did not quite understand how Mr. Ingpen 
would get rid of the disturbing elements in his calculations, when 
eye-pieces having different foci were used. The eye-pieces of no two 
makers were just alike. 
Mr. Ingpen said the proposed use of the standard was not so much 
for competition as for real practical purposes. It was to enable the 
microscopist to place any objective that might come into his hands 
under the conditions in which he would ordinarily use that objective, 
and then to test its aperture by a standard which must, or must not, 
be recognized by other persons. 
Mr. Brooke asked Mr. Ingpen whether there was any practical 
