he water in washing
was in this case also very small, the potash required for neutralizing
equaling 1.02 per cent. of the weight of oil.

I found that the cakes of acids were solid at 36 deg. C., and were
completely melted at 39 deg.

On solution in alcohol, and digestion for two days with animal
charcoal, the color was much diminished, and on the liquid being
filtered and cooled to 0 deg. C., an abundance of small white
crystalline plates separated out, which, when dried, melted at 67 deg. C.

The crude fatty acids turn black with sulphuric acid, as the oil
does, and yield a similar substance with nitric acid. It is similar
in appearance, but differs in that it melts at about 50 deg. C., and
is soluble in glacial acetic acid, which is not the case with the
substance from the oil.

These fatty acids crystallize on cooling, in a most characteristic and
beautiful way, forming wavy circular plates totally unlike any that I
have seen before.

The above experiments may, I think, be taken as conclusive as to
the nature of tea oil and cabbage oil. The former may certainly
be considered a useful lubricating agent for the finer kinds of
machinery. The work upon wood oil is not yet sufficiently complete to
show us the nature of its proximate constituents. I am continuing the
examination of this oil. Perhaps I need scarcely add that there is no
connection between this "wood oil" and the Gurgun balsam, the product
of _Dipterocarpus turbinatus_, which is also known as "wood oil."

* * * * *

THE OTOSCOPE.

Prof. Leon Le Fort has recently presented to the Academy of Medicine,
in the name of Dr. Rattel, a new otoscope, which we illustrate
herewith.

The first person to whom the idea occurred to illuminate the ear was
Fabricius d'Acquapendentus (1600). To do this he placed the patient in
front of a window in such a way as to cause the luminous rays to enter
the external auditory canal. It was he likewise who conceived the
idea of placing a light behind a bottle filled with water, and of
projecting its concentrated rays into the ear.

In 1585 Fabricius de Hilden invented the speculum auris. This
instrument was employed by him for the first time under the following
circumstances: A girl ten years of age had in playing introduced
a small glass ball into her left ear, and four surgeons, called in
successively and at different times, had been unable to extract
it. Meanwhile the little pat