Mineral Point tribune. (Mineral Point, Wis.) 1869-1938, 1876-12-06
MECHANICAL AND SCIENTIFIC.

ALOHANAVAL AND SClENT1FlCs
"A substitute for gunpowder has been
invented in England. 1t consists Of
a little powdered charcoal and finder
wrapped >. a paper impregnated with
a chemical combination OF chlorate,
nitrate, p'ussiate and chromate of pot
ash. The advantages claimed are that
no danger of explosion exists except
from actual contact with fire the in
terror of the tirearm is not soiled, less
smoke and less rebound are made than
with gunpowder, and less damage takes
place from humidity.
The caterpillars which feed upon
the potato and tomato, and generally
known as the tomato worm, are the
Larvae of the fiye-spotted sphinx moth
(sphinT quinq,temaculata). The
worms, before changing to chrisa-
lides, descend into the soft earth be-
meath the plants upon which they have
been feeding, sometimes burying
themselves several inches in depth, if
the soil Is of a loose nature, but if it is
hard they will rest under the old leaves
and rubbish, scarcely covering them
selves with earth.
According to some interesting ex-
periments recently made in Stuttgart,
it has been found that bricks which
have been coated three times with lin
seed oil are less smeary, from wear. in
wet weather, as well as more free from
dust in summer, than those not sub
jected to this kind of treatment. The
cheaper petroleum residues. it appears,
may be economically employed. in
stead of the linseed oil. Saturation of
paving bricks, sandstone, etc, about
manufactures, with hot tar, is also
recommended as advantageous, where
the black color is not Objectionable.
Fifty thousand dollars is yearly
spent upon the purchase of printed
books for the British Museum, al
though copies Of those published in the
United Kingdom are obtained gratis.
whereas the miserable pittance of
81, POO is allowed for geological speci-
mems, $500 for fossils, and f4OO for
botany. The general level Of the 700
logical and botanical collections in the
British Museum is undoubtedly far
below what it ought to be. The finest
SPECIMENS in nearly every department
of natural history fall into the hands
of amateurs because the National col
lection is so badly supplied with funds
for purchases of this kind.
With reference to color blindness,
or the lack of power to distinguish col
ors. it is stated that very few of the
persons so affected are conscious of the
defect in their vision. Many railroad
accidents are caused by the color blind
ness of railway employees, and the
Swedish railway direction had recent
ly ordered an examination to be made
by OculiStS of all the men in its employ,
so as to guard against the danger.
Prof. Holmgren, who has just exam
ined the employees of the Upsal Getle
Railway, found that, out of 266 persons
examined, eighteen were color blind,
and 50 utterly untitled for the railway
service.
The property Of infusorial earth
which enables it to take up five times
its own weight of liquid, and to suck
it up rapidly without becoming fluid.
has led to its substitution for the filter
press to considerable extent in Ger
many; it being simply necessary to
surround the filter with layer of dry
infusoria in order to obtain, in very
short space of time, the same result
that Is attained by ordinary filtration
in DAYS or even weeks. Simple drying
restores to the infusoral earth its alb
sorptive power. Owing, too. to its
great volume and slight weight, it is
employed also for packing very fragile
objects and glass apparatus, etc, and
mixing with plaster of Paris for max
ing light casts. N. J. SIN.
1t is well known that the Gramme
magneto-electric machine, which
transforms mechanical force into cleo
tricity, can also be employed in in
verse manner to transform electricity
into mechanical force. According to
the Scientific american, this property
may be utilized to transmit power
over long distances. The motor of
factory, for example, could be con-
nected with one machine SO as to ro-
tate the same and thus generate cur
rent-which current, carried over
distances by cables, might be commu-
nicated to another Gramme machine at
the point where the power is required,
and the second machine, by the cur
rent, would thus be caused to revolve,
and the power would be utilized as
necessary. OF course, in this double
operation, there is loss but accord
ing to NJ. Magnon, who has inyesti-
gated the whole subject experiment
ally, this loss is even less than that
which takes place with any other me-
chanical disposition.