l. v.,
p. 181.

The slight differences in size accurately given in this table are not
always appreciable under modern amplification, but under a power of
1,150 diameters "corpuscles differing by the 1-100000 of an inch are
readily discriminated." For the conclusions of Prof. Wormley as regards
the possibility of identifying blood of different animals, the reader is
referred to his book on Micro-Chemistry of Poisons.--_Amer. Micro.
Jour._

* * * * *

THE ABSORPTION OF PETROLEUM OINTMENT AND LARD BY THE SKIN.

[Footnote: From the _American Druggist_.]

E. Joerss has investigated the question whether ointments made with
vaseline or other petroleum ointments are really as difficult of
resorption by the skin, or of yielding their medicinal ingredients to
the latter, as has been asserted. In solving this question, he
considered himself justified in drawing conclusions from the manner in
which such compounds behaved toward _dead_ animal membrane. If any kind
of osmosis could take place, he argued, from ointments prepared with
vaseline, etc., through dead membranes, such osmosis would most probably
also take place through living membranes. At all events, the endosmotic
or exosmotic action of the skin of a living body must necessarily play
an important _role_ in the absorption of medicinal agents; and, on the
other hand, it is plain that fats, which render the living skin
impermeable, necessarily also diminish or entirely neutralize its
osmotic action. To test this, the author made the following experiments:

Bladder was tied over the necks of three wide-mouthed vials, with
bottoms cut off, and each was filled with iodide of potassium ointment.

No. 1 contained an ointment made with lard.

No. 2, one made with unguentum paraffini (_Germ. Pharm_.), and

No. 3, one made with unguentum paraffini mixed with 3 per cent. of lard.

All three vials were then suspended in beakers filled with water. After
standing twenty-four hours at the ordinary temperature, the contents of
none of the beakers gave any iodine reaction. After having been placed
into a warm temperature, between 25-37 deg. C., all three showed iodine
reactions after three hours, Nos. 2 and 3 very strongly, No. 1 (with
lard alone) very faintly.

The same experiment was now repeated, with the precaution that the
bladder was previously washed completely free from chlorine. Each vial
was suspended, at a temperature of 25-27 d