308 General Notes. [May, 
such diversions as public exhibitions and a moderate amount of “ micro- 
scopic gymnastics” in the way of “ test-object” resolution. Mr. Kinne’s 
paper on the method by which a fly walks in an inverted position was ' 
brought so strongly before the attention of the publishers of a school- 
book in which the familiar facts of the case were misrepresented, that 
they promised to suppress the erroneous article in future editions. The 
excellent annual address of the president, Prof. Wm. Ashburner, recom- 
mends that, in addition to the advantages furnished to members, the 
privileges of the rooms be extended to investigators who might not be 
able to ineur the expense of regular membership. 
Kinne’s TurN-TABLE. — This is a self-centring table in which the 
object is held diagonally between rectangular clutches, as in the “ Cox 
table.” This was contrived independently, though published subse- 
quently to Mr. Cox’s invention, from which it differs in moving the 
clutches by a lever and spiral instead of a screw. 
Comparative Puorocrarus or Bioop. — Dr. J. G. Richardson, 
for the sake of illustrating in criminal cases the distinguishable appear- 
ances of different kinds of blood, has flowed drops of blood from differ- 
ent animals so nearly in contact on the glass slide that portions of the 
two drops appear in the same field and can be photographed together. 
Dr. C. Leo Mees has modified this method and obtained exquisite results 
in specimens presented to the microscopical section of the Tyndall Asso- 
ciation. He spreads the blood by Dr. Christopher Johnson’s method, 
which is to touch a drop of blood to the accurately ground edge of a 
slide, and then draw it gently across the face of another slide, leaving a 
beautifully spread film. In this way one kind of blood is spread upon 
the slide and another on the cover. When dry, one half of each is care- 
fully scraped off with a smoothly sharpened knife, and the cover inverted 
upon the slide in such position as to bring the remaining portions of the 
film into apposition. Under the microscope and in the photograph the 
two kinds of blood appear in remarkably fine contrast, even those bl th 
that are too nearly alike for safe discrimination in criminal cases being 
easily distinguished when thus prepared from fresh material. 
“Rusty Goup.” — Mr. Melville Attwood, in his paper on thi 
before the San Francisco Microscopical Society, discredits the 
the miners that a thin film of oxide of iron forms on gold and prevents 
a successful separation of the gold by means of amalgamation. He be- 
lieves the failure of the miners to obtain good results to be due far 
more to an unexpected poverty of the quartz than to any difficulty 12 
causing the quicksilver to combine with the gold that is really present Ț 
Excuances. — (Notices, not exceeding four lines in length, of mi- 
croscopical objects or apparatus wanted or offered in exchange, not sale, 
will be inserted in this column without expense.) 
Diatoms, prepared or unprepared, in exchange for others. Corre: 
spondence desired with amateurs interested in mounting arranged dia- 
s subject 
belief of 
