The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1868-07-09
SCIENCE.

NATURAL ANILINE.-The mollusk, commonly
called the sea. hare, found in large numbers on
the coast of Portugal, exudes, as a means of
defense an offensive cOloring matter, which
has been analyzed by NJ. ZeigleT of MulhOuse,
who has asCeTtained that it is composed prin-
oipally Of aniline. All the species of molusca
included under the general name of murex,
yield dye which was supposed to be the
same as that used by the Phmnicians for pro-
ducing the famous Tyrisn purple; but NJ.
Zeigler now suggests that the costly coloring
material, held in high repute among the an
clients, was probably obtained from the AplySid
or sea-hare. 1t must, however, be said to the
credit of Chemistry, that by her processes the
ordinary cealtar is made to yield aniline at
cheaper rate than it can now be obtained from
the same sources to which it is supposed the
ancients had recourse for their supply.
SOULS VERSUS OARs.-During late discus
sion on the slip of screw-propellers, at the In
sttuton of Naval Architects London, the
Chairman, Vice Admiral Belcher, incidentally
said he wanted to know how it was that
Japanese vessel of IS or 20 tons, pulling
against his 30 ton gig, with lS-feet oars, beat
them Out-and out with two sculls There
were four men at each scull, the sculls being
in the direction of the axis of the vessel. The
two sculls drove the Japanese vessel ahead
faster than his gig could follow. The distance
the sculls passed through the water could not
have been above six or eight inches, and it
was only the bend of the oar which gave dia-
gonal jerk to the vessel. The question was
not there answered, but it is evident the
Japanese scullers had an advantage in an
almost continuous application of their power.
In Venice, the gondola is often driven by a
single scull held, not behind, but on the side
of the vessel, and worked to the right and
left, without being raised from the water.
Thus the expert gondolier propels and steers
his craft with the same paddle.
CHAMPAGNE FROM PETRoLEUM.-The beauti-
full synthetic process of which Berthelot sue
ceeded in combining mOecule of Clifant gas
with a molecule of water and thus forming
alcohol, has led to experiments with hydro
carbons of the Marsh gas series which, it is
said, have resulted in the production Of an
alcoholic beverage. In this day of adultera-
tions it may be useless TO warn those who may
require alcohol for medicinal purposes against
the use of any decoctions containing spirit not
made from sugar, grain, or the grape. The
real safeguard, however, against this class oi
adulterations lies in the fact that no chemist
has yet succeeded in producing, from hydro
carbOns, alcohol at as low cost as it can be
made from Indian corn; and further, in the
probability that the large area OF land now
being devoted to vineyards will result in thu
production of mild wines much cheaper thar
''doctored' dilutions of corn whisky, consti
tutiDg the imitation.
= w
Robinson of the University of Michigan pro
poses to the engineer who wishes to determine
the pressure to which his boiler can be worked
with safety, the following very simple pro
cers:-Let the boiler be filed entirely full O
cold water, even to the throttle of the safet.
valves, and all closed tight to prevent an.
escape. Now, by lighting fire under tn
boiler, the water will be gradually expanded
and produce pressure sufficient even to rup
ture the iron before the temperature of tn
water arrives at the boiling point While tn
pressure is increasing, let the steam gaug
or pressure indicator be watched; and whel
the test PRESSURE which may be twice or NOR
times as great as the working pressure,
reached, a portion of the water may /
allowed to escape and the pressure reduced
The pressure results from the fact that wate
expands more by heat than iron, at a CORES
pOnding temperature. The process give
above is attended with as much safety as th
use of the hydrostatic press, unless the wate
be heated over 2l2 degrees F., which woul
rot be required unless the boiler leaks. Belo
this temperature no disastrous consequence
would follow even if the boiler should
torn asunder, inasmuch as explosions resu
from the sudden expansion of gases or vapor