11 
for the Society’s album, of a fine photograph of the Treasurer, Mr. 
Horne, from Mr. T. H. HENNAH, 
Votes of thanks were given to the donors. 
SEPTEMBER 26TH. 
MICROSCOPICAL MEETING.—MR. J. H. HENNAH ON 
A NEW SERIES OF LENSES BY WENHAM. 
Some would recollect seeing the new patent objectives at the Asso- 
ciation Soirées ; but Mr. Wenham kindly promised to send some down 
for exhibition to the Society. They were stated by Mr. Wenham to be 
on a perfectly new method of construction, two or three of the lenses 
of the older construction being dispensed with and a single front 
and back lens used. It was hoped thus to obtain a cheaper series of 
object glasses; but that would be no advantage unless better perfor- 
mance was also secured. Those sent down were all very good,—but 
he would advise the members to wait for still greater improvements. 
The 1-15th was an exquisite glass when properly adjusted, which, ex- 
cept in the hands of an experienced microscopist, was not easy of 
accomplishment. The 1-1oth he considered a good glass, with a 
_ good working distance. They could be used as dry or immersion 
lenses. At present there was an inequality, for, while very good as 
dry on some objects, they were not so good when wet, and vice versd ; 
but on some objects the performance was equally good, whether wet or 
dry. 
He had written to Mr. Wenham on the subject of a lens with 
moderate angle of aperture for naturalist’s work, because he did not 
believe in the high-angled glasses at present in use, and he would read 
what Mr. Wenham said :—“ I agree with you that a one-twentieth of 
about 95°, with corrected aperture (I do not mean a large aperture cw 
down to 95°), but a system just worked up to that aperture, so as to 
have a long focal distance, say one-thirtieth of an inch, would bea 
most valuable glass in the hands of the naturalist, enabling him to 
