THE MICRUSCOPE. 249 
* Isonation, Srarninc anpd Movunrine or Corneat Crtis.*—The 
method of His, modified by Ranvier, gives excellent results. Place 
a small piece of the fresh unmanipulated cornea in a mixture con- 
sisting of sulphuric acid and distilled water in equal parts, and keep 
it there for a few moments or until the basal substance softens. 
Pour off the acid mixture and replace it with distilled water. Lift 
the bit of cornea on to a slide and put on a cover-glass, pressing the 
latter to place with a light to and fro motion. This suffices to loosen 
and separate a vast number of individual cells, or of lamellee of them, 
which can be examined in situ. A minute drop of a solution of 
fuchsin, sulphate of rosanilin, or anilin-red, may be added, and it 
imparts a permanent stain to the cells which brings out all the de- 
tails beautifully. For permanent mounting, glycerin should be 
used. In these preparations the stellate cells, anostomosed by 
prolongations of the points, are finely shown, though the nuclei are 
not seen. This method also shows the image crests, cretes d’ 
empreinte, now well-known. 
Exectrro-Grapxoscope.t—At the recent conversatione of the 
Royal Society at Burlington House, given by Prof. G. G. Stokes, 
M. A., President, a new adjunct to the optic lantern, invented by Mr. 
Eric 8. Bruce, was exhibited. It consisted of a white lath about an 
inch wide and eighteen inches long, which was made to rotate 
windmill-fashion by an electro-magnetic motor. A picture then 
thrown on the rotating lath by the magic lantern was visible in its 
entirety, on the principle of the retention of vision. The back- 
ground some distance behind the lath was also visible, hence the 
picture cast by the lantern, which was one representing a statue, 
seemed to stand out in mid air. 
PATHOLOGY. ¢ 
Tae Micro-orGanismM oF Pertussis (WHooprine CoueH).§$—In 
1870 Lezerich discovered micro-organisms in the sputum of pertussis, 
which on further investigation turned out to be a harmless Sapro- 
phyte. Tschamer found a fungus, Capnodium citri, but this is also 
found in oranges and apples. Deichler discovered an organism be- 
longing to the protozoa, evidently not the pathogenic microbe of the 
disease. Herke describes small round cells, clearly only lymph 
*St. Louis Medical and Surgical Journal, July, 1859, p. 44. 
+ Popular Science News, July, 1889; p. 99. 
_  fUnder this heading will be included all Abstracts relating to the Histology of 
Diseased Tissues, both Animal and Vegetable. 
§Medical News, June 2, 1889, p. 598, 
