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NOTES AND MEMORANDA. 
correct, having obtained credence at a period when the difficulties 
attending their construction had not been thoroughly mastered ; but 
that such is no longer the case. I feel sure that the advanced workers 
of this country already accept as true the conclusions arrived at by 
our committee ; hut I am also sure that by far the greater number of 
our microscopists still hold to the old faith.” 
It is hardly necessary to point out the absurdity of the statements 
made above, hut their having been published in a journal of so good a 
repute as the ‘ American Naturalist ’ demands that they shall receive 
immediate contradiction. In the first place, the fixed law which Mr. 
Dod refers to is the very opposite. Dr. Carpenter refers to the sub- 
ject in the most guarded language, and all that can he gathered from 
his statement is the fact that men who are engaged in real microscopic 
work prefer glasses with small angles to the very wide-angled objec- 
tives. And in this we can assure Mr. Dod that almost every worker 
with the microscope on this side of the Atlantic will most distinctly 
concur. Dr. Carpenter’s position is this : that of two objectives, one 
of moderate angle (say a ^th of 75°, or a ^th of 90°) and another of 
wide angle (say 120° and 140°), equally well corrected, the one of mode- 
rate angle will be better for all ordinary work than that of the high 
angular aperture. And this universally admitted fact is shown very 
fully in the present number by the able paper of Mr. Slack. But it is 
necessary to point out where Mr. Dod has most probably erred. It 
is needless to indicate that his glass of 180° is manifestly an utter 
impossibility. But what we would say is this : that there is no state- 
ment made by Mr. Dod, as to whose glasses were tried, and we have no 
evidence as to whether they were perfectly corrected or not. It is 
quite possible that a glass whose corrections were imperfectly made 
would break down under a deep eye-piece. But then such a glass 
cannot be a good one. Besides, Mr. Dod does not state how much of 
his object he saw at once, a point of some importance. Altogether, 
we cannot congratulate the Memphis Microscopical Society on the 
wisdom of their latest move. 
A Grant for Inquiries on Staining Reagents in Microscopic 
Anatomy has just been made by the Royal Irish Academy, to the 
extent of 25Z., to Dr. Reuben Harvey. The sum is not very much, 
hut the granting of it is a step in the right direction, and we are glad 
to see that the academicians have adopted it. 
The Locality of the Bermuda Tripoli. — We have received the 
following note on this subject, which was originally communicated 
to the Boston Society of Natural History, at a recent meeting : 
The Secretary read a note by Mr. Charles Stodder, on the locality 
of the Bermuda Tripoli, accompanied by a communication on the same 
subject by Professor Christopher Johnston, of Baltimore. In ‘ Science 
Gossip,’ London, for May, 1874, is a note signed “ F. K.,” in reply to 
a correspondent who had inquired for the locality of the celebrated 
“ Bermuda Tripoli,” so rich in peculiar forms of Diatomacefe, described 
by Ehrenberg and the late Professor J. W. Bailey. “ F. K.” says 
that “ Mr. Geo. Norman, of Hull, England, found that it came from 
