The Savannah morning news., 1902-07-09

ent contrivance which in the darkest
night shows the flight of shell, says
the Chicago Tribune. The Illuminating
chaser is the invention of Pittsburg
man, who believed that gunners would
be able to do more effective work if
they could see where the shots from
their guns struck. At the Indian Head
proving grounds several one-pound
shells, fitted with the contrivance.. were
fired in the dusk of the evening, and
rather good results were obtained. In
the tests aboard the kearsarge the pro-
jectiles will be discharged in the full
glare of the Searchights to determine
whether the Illuminating chaser can
still be sesn. The invention will be OF
value especially for the rapid fire guns
of small calibre. 1t was explained that
man operating rapid fire gun has
little opportunity to sight the weapon,
! especially at night, and if he can see
where the projectiles are falling he
can use the weapon as a man does a
hose.
1t is well known that many diseases
are propagated by vermin. Flies trans
port tuberculosis, mosquitoes yellow
fever and malaria, rats the plague.
Mr.. v. Haazen in the Annales de Phar-
| macie reports the results of expert
ments on the destruction of vermin
| that are of immediate practical impor-
tance. Bedbugs resist exposure for
| twenty-four hours to an atmos phere
containing six grams of formic aide
hyde per cubic meter. With eight
grains certain number died. All per-
lshed with nine grains per cubic meter.
The gas furnished by the burning of
| twenty-five grain. of sulphur per cubic
meter also destroyed all these pests
Flies and mosquitoes are killed by two
grains of fornic aldehyde per cubic
meter of air. Fleas are destroyed by
seven grains per cubic meter, or by
burning sulphur. Rats and mice are
destroyed by thirty-six hours exposure
to an atmosphere containing fifteen
grains of formic aldehyde per cubic
meter, but the full exposure of thirty
six hours must be given; twenty-four
hours is not sufficient.
Every student and observer in ma
ture, says the Chicago Tribune, soon
| learns that the spider remains in the
! center of the wen that it may feel the
slightest motion caused by any luck
| less insect which has been caught in
the sticky substance. Now, if one will
| look closely at the spider he will see
that 1t hangs head downward. One
day, by suddenly frightening a spider
| slant position upside down in the web
1t dropped head down, and stopped
when about halfway to the ground, and
swung slowly to and fro from the end
| OF long thread of web. If it had been
head up in the web it would have turn
| ed somersault and the web would
have been broken. After the spider
had swung at the end of it's web for
some time it thought all danger had
| passed, and turned and climbed up
| again. 1t rolled the web thread up
with it's forelegs. and then threw it to
the ground. This was evidently done
to keep it from becoming tangled with
any of the web proper, or with grass
or weeds nearby. Any one who has
touched a web knows that it is sticky
and hard to ravel when once tangled
Certainly, this bit CT instinct is not
absent from the spiders brain.
The work of counting the census
returns of the United States is ia
| cilitated by machines working auto
matically. The system consists in re-
cording on cardboard, by means of
holes perforated at suitable places, the
| indications of the separate census re-
| turns or bulletins. The cardboards are
| then placed in a machine, which auto
| matically turns up the data fed into
| it. The machine has series of points
| corresponding to all possible positions
of the perforations. Wherever hole
| exists 1t is traversed by one of the
points. which passes through it into
| contact with cup of quicksilver
| placed below the cardboard, and this
| contact completes an electric circuit
| that acts on registering apparatus.
| Unless card has been perforated at
| a given point no record is made. There
are five sorts of cards-for individuals
for families, for mortality, for farms
and for harvests. At the last census
there were used. in round numbers.
about 100000 farm cards, lis, 0o0, 900
harvest cards, 100000 individual
cards, 100000 family cards and L.
100000 mortality cards. Some 5000 to
| 10000 cards can be handled by each
machine without error. The system
thus described in it's larger outlines has
been perfected in many details and is
regarded as fully successful.
The pressure of light impinging on
bodies, first predicted by Maxwell, has
| lately been actually measured. The
and the earth, for example, is very
| great and amounts to about 100000
00,00o00O dynes. The gravitational at
traction between the two bodies is, of
course, very much greater; it is, in
| fact, about 10000. 900, 100000 times as
great. Prof. Woodward concludes his
| address with the remark that it is a
curious and a puzzling, though perfect
~ obvious, fact, that mankind as a
| whole lives far less in the thought of
| the present than in the thought of the
| past, and that as race we have more
| respect for the myths of antiquity than
| we have for the certainties of exact
/ science. From time inlmemorial tradi-
| ton has dominated reason in the mass
| es of men. Each race has lived under
| the sway of the thought of some pre-
| ceding age. AS a vigorous thinker he
| regrets the waste of human effort and
| of human time. Those who are in
| terested in this aspect of the subject
will do well to compare This address
with one by DR.. Langley on the Laws
! of Nature" printed in Science for June
! 13. His contention is that there are
| no laws of nature no certainties of
| exact science. The discrepancy in con-
illusions is not difficult to unravel, but
there is no space here available Read
! ers are advised to see the two addresses
in question.
When English officers in India want
venturesome sport. says the New York
Press, they invade the jungle with ele-
plants and horses in search of tigers,
usually hunting for one that has har-
assed native village. At the English
clubs in Bombay or Calcutta says a
| writer in Ainslee's Magazine one NAV