Scientific American Supplement, No. 443, June 28, 1884Various
Science
Scientific American Supplement, No. 443, June 28, 1884
Various
Science -- Periodicals
3. If the ratio is above 3.8, it is very probable that Japanese or
carnauba wax or grease has been added.
4. If the ratio falls below 3.6, stearic acid or resin has been used
as the adulterant.
* * * * *
PHENOL IN THE STEM, LEAVES, AND CONES OF PINUS SYLVESTRIS.
A DISCOVERY BEARING ON THE FLORA OF THE CARBONIFEROUS EPOCH AND THE
FORMATION OF PETROLEUM.
By A.B. GRIFFITHS, Ph.D., F.C.S. Membre de la Societe Chimique de
Paris, Medallist in Chemistry and Botany, etc.
Having found, in small quantities, alcohols of the C_{n}H_{2n-7}
series, last summer, in the stem, acicular leaves, and cones of _Pinus
sylvestris_, I wish in this paper to say a few words on the subject.
First of all, I took a number of cones, cut them up into small pieces,
and placed them in a large glass beaker, then nearly filled it with
distilled water, and heated to about 80 deg. C., keeping the decoction at
this temperature for about half an hour, I occasionally stirred with a
glass rod, and then allowed it to cool, and filtered. This filtrate
was then evaporated nearly to dryness, when a small quantity of
six-sided prisms crystallized out, which subsequently were found to be
the hydrate of phenol (C_{6}H_{5}HO)_{2}H_{2}O. Its melting point was
found to be 17.2 deg. C. Further, the crystals already referred to were
dissolved in ether, and then allowed to evaporate, when long colorless
needles were obtained, which, on being placed in a dry test tube and
the tube placed in a water bath kept at 42 deg. C., were found to melt;
and on making a careful combustion analysis of these crystals, the
following composition was obtained:
Carbon 76.6
Hydrogen 6.4
Oxygen 17.0
-----
100.0
This gives C_{6}H_{6}O, which is the formula for phenol.
On dissolving some of these crystals in water (excess) and adding
ferric chloride, a beautiful violet color was imparted to the
solution. To another aqueous solution of the crystals was added
bromine water, and a white precipitate was obtained, consisting of
tribromophenol. An aqueous solution of the crystals immediately
coagulated albumen.
All these reactions show that the phenol occurs in the free state in
the cones of this plant. In the same manner I treated the acicular
leaves, and portions of the stem separately, both being previously cut
up into small pieces, and from both I obtained phenol.
I have ascertained the relative amount of phenol in each part of the
plant operated upon; by heating the stem with water at 80 deg. C., and
filtering, and repeating this operation until the aqueous filtrate
gave no violet color with ferric chloride and no white precipitate
with bromine water.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account