Daily globe. [volume] (St. Paul, Minn.) 1878-1884, 1879-03-09
Scientific Gossip.

Arsenic in the green leather lining of
the helmets worn by some soldiers at
Konlgsberg caused troublesome erup.
tons,
A coating of soluble glass on caoutchoue
tubes will, it is said, render them imper-
Vious to coal gas.
Lead has been found by SchuIzenberg-
er IN new and remarkable condition. and
he cites this as another example of allo-
tropism by electrolysis.
M. Depelly, in LIS Mondes, proposes a
continuance by which the date when the
letter passes through the post office will
be made to appear not only on the enve-
lope, but on the letter inclosed.
DR.. Carnelly finds that of 81 elements
rs show that the coeffcient of expansion
increraes as the melting point dlm1nishes.
The five exceptions are arsenic, antimonv,
Dismuth, telurium, and tin.
Following up the Investigations of DR..
Draper on radiations, M. Crova has
selected certain number of de
terminate wave lengths between the
Fraunhofer lines B and G., and has meas
ured the intensities of the radiations cor
responding to them from the sun, the
electric light, the Erummond light. and
the moderator lamp. lie found the
weakening of the intensity toward the
violet was very different in different cases.
In the solar spectrum it fell from 1000
to 400, and in tie moderator lamp from
LOCO to ~ for the same variation of wave
length.
An interesting paper on the effect of
the motion of the air within an auditor
lum upon its acoustic properties, is con-
trlbuter Dy W. w. Jacques, Fellow in
Physics of the Johns Hopkins University.
to the Journal Of tie Franklin Institute.
Preachers, singers, actors, and public
speakers generally will find valuable sug-
gestlons indicated by it. Mr.. Jacques has
repeated Tyndall's experiments with
some notifications, and arrived not onlv
at the conclusion that currents of air
OF varying density form one of the chief
obstacles to the propagation of sound,
but that they actually modify the sound
wave, and so give rise to great indist1nct-
ness.
A report on street rails, presented bv
Charles B. Dudley Of the Pennsylvania
Railroad Company, concludes that with
our metallurgical methods high phes-
phorus Cover 0.10 per cent? is inconsistent
with safety; that silicon should be as
low as is consistent with the successful
working of the Bessemer process (not
above 0.O4 per cent? that the best range
for carbon is from O25 per cent. to OBS
per cent; that the total of the hardeners
expressed in phosphorus units should not
be above 81 to 80, nor below 25; that the
tensil strength shoula be $4,000 pounds
per square Inch, and that the PERCENTAGE
of elongation should be above 20 per cent
| Mr.. John Hammes has reported tc
Rear-Admiral Rogers, of the United
States Naval Observatory, that on Nov
10, 1878, $50 P. NJ. civil time, he saw q
volcanic eruption on the moon in the
vicinity of Baco, Barocius, and Nicolai
while looking through 6-1-2-1nch tele.
scope, at Oska!oosa Iowa. The matte,
elected took a tan-like form and Hammes
says the spectacle continued for half ar
hour, and was seen by him as plainly as
''any other mountain scenery in the moou
is seen, and Of the same color" Rear.
Admiral Rogers has intimated to his cor.
respondent that his observation twill be
attributed to some chance dust on the
glass, or to some error OF adjustment, OF
to an accidental light reflected from some
neighbours window, or to some other
source of error"
At the meeting of the Franklin Insti.
tute on Nov. 90, Dr. Isaac Morris, Jr.
exhibited modification of the micro.
phone for stethoscopic purposes. It il
IKE the ordinary Bell telephone, but with
the magnet and coil replaced by metal
tic tube which can be adjusted endwise
ny means of a screw at the end ef the
handle. A small carbon cup is inserted
at the end nearest the diaphragm. TIC
the centre of the inner side of the
diaphragm another short tube is attached
having also carbon cup Each tube is
connected to binding posts. A pointed
piece of carbon rests on the two carbon
cups, which are placed half an inch apart,
and the circuit is completed with a Bell
telephone. This instrument is very del
cate; but though the P Philadelphia College
OF Physicians have been favorably i'm.
pressed by it, in certain positions it does
not work we'll.