1883.] Microscopy. 345 
BIBLIOTHECA AMERICANA.—Robert Clarke & Co., Cincinnati, 
have issued a catalogue of books and pamphlets relating to Amer- 
ica, containing 6589 titles, with prices. Many of these works are 
rare and some of them almost out of the market. A reprint of 
John Leith’s travels and captivity among the Indians, covering a 
period of eighteen years (1774-1792), in a limited edition, is an- 
nounced. The same firm advertises Shea’s Mississippi series in 
three volumes, and Dr. Brinton’s Library of Aboriginal American 
Literature, the first number of which is now rea y. 
MICROSCOPY.! 
THE USE OF CHLOROFORM PREPARATORY TO IMBEDDING IN PAR- 
AFFINE.—As is well known to all who are familiar with the use of 
the microtome, objects to be imbedded in paraffine must be satu- 
rated with some solvent of paraffine. It has been found that the 
different solvents do not all give equally good results. The use 
of chloroform, which is now coming into general use, was first 
Proposed by Dr. Giesbrecht? of the Zodlogical Station at Naples; 
but was soon afterwards recommended by Professor Biitschli,> to 
whom the Journal of the Royal Mic. Society (Oct., 1882, p. 708) 
has inadvertently given the credit of the discovery. Chloroform 
is unquestionably superior, in certain important respects, to oil 
ot cloves, creosote or turpentine. Jt is particularly to be recom- 
mended where there is danger of shrinking and brittleness. The 
od of using it has been briefly stated in the October number 
of this journal (p. 783). 
In the Zoologischer Anzeiger, No. 129, p. 20, Professor Koss- 
mann, of Heidelberg, says that chloroform is the only solvent 
that can be successfully used in the case of objects with thick 
chitinous membranes. 
n paraffine, and the complete evaporation of the chloroform before 
the object is finally imbedded. If the first point is not secured, of 
Course the paraffine will not penetrate the object thoroughly ; and 
if the chloroform does not wholly escape before the process of 
| g begins, the paraffine will be spongy, and consequently 
unfit for section-cutting. The evaporation of the chloroform may 
be effected in two or more ways. In all cases the object must lie 
je = loroform until thoroughly saturated. Then paraffine may be 
i gradually, as recommended by Dr. Giesbrecht; or the 
form, as object may be placed in a solution of paraffine in chloro- 
aS recommended by Professor Bütschli. After remaining 
here unti 
l it is thoroughly impregnated (an hour or less), it may 
1Edit it 
tp: by Dr. C. O. WHITMAN, Newton Highlands, Mass. 
” 'esbrecht, t, “ Zur Schneide-Technik.” Zool. Anzeiger, 1881, No. 92. 
' Bütschli + Biol. Centralblatt, vol. 1, p. 591 (1881). 
