PROCEEDINGS OF SOCIETIES. 293 
gave a spectrum unlike any I have yet seen, and perhaps may 
lead to some interesting results. It was a case in which the old 
plan would not have answered at all.” 
June 9th.—“ I spent the whole of yesterday and to-day in most 
carefully going over all sorts of test-objects with the new prisms, 
making, and trying, a great variety of schemes. On the whole, 
the improvement we have effected is most striking. Unless you 
had worked with the original arrangement I think you would 
hardly believe the advantages of using the prism over the eye-piece. 
One can in this manner overcome the effect of partial opacity. I 
haye contrived a slit to put into the eye-piece, which can be made 
broad, so that the object can be distinctly seen, and then narrow 
for use; and also arranged it so that the length of the slit can be 
made either the whole width of the field or very narrow. This is 
a great advantage in looking at small objects in large sections of 
rocks, &¢., for one can see before putting on the prism that only 
the object under examination is behind the open part of the slit.” 
June 12th._—* The best tests are—Ist, that the absorption-bands 
in blood can be seen when they are very faint; 2nd, to well 
divide the bands in a very dilute solution of permanganate of 
potash; and 3rd, to see distinctly the very fine lne given in the 
red by a very pale blue solution of chloride of cobalt, in a concen- 
trated solution of chloride of calcium. This is so fine that it 
looks like a Fraunhofer’s line. A dispersive power that will show 
all these well is about all that one could wish. The combined 
prisms do this.” 
PRESENTATIONS TO THE MICROSCOPICAL SOCIETY. 
May 10th, 1865. 
Presented by 
On the Parasitic Origin of Pleuro-pneumonia in Cattle. 7 
By Thomas Shearman Ralph, Esq., M.R.C.S. . The Author. 
Sidereal Chromatics ; being a Reprint from the “ Bed- 
ford Cycle of Celestial Objects,” and its “ Hartwell 
Continuation ” on the Colours of Multiple Stars. 
By Admiral W. H. Smyth, R.S.F., &. &e. on Dittos 
Hamatologische Studien. Von Dr. Alex. Schmidt . Ditto. 
Quarterly Journal of the Geological Society, No. 82 . The Society. 
Transactions of the Linnean Soclety, Vol. 24 a Ditto: 
Proceedings of the Academy of Natural Sciences of 
Philadelphia, Nos. lto5 ©. ; . Ditto. 
Popular Science Review, No. 15. : . The Editor, 
Tntellectual Observer, No. 39 : ; : 
The Annals and Magazine of Natural History, Nos, 88 
and 89. i : ‘ . Purchased. 
Bight Slides of the oldest known Fossil, Hozoou cana- Dr. W.B. 
densis , . ‘ é Carpenter: 
Ditto. 
