The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1897-10-31

tirely luminous The phosphorescencs,
which is under control has the bright
greentsh color Of the glow worms light.
and when IN glow its secretion Is luminous,
making 8 luminous trail At night stamp
ing on the ground or slight pressure causes
the creatures to come to the surface and
light up.
The firing of candle through a door or
pine plank VIII no longer excite our Won
der. A more striking illustration OF the
penetrative power of light matter at high
velocity has been furnished by Captain
Cooper Key r. A.. as a result Of firing gas
in mines. For a bore-hole was employed a
special gun, which was charged with high
explosive. tamped by pressed cylinders OF
raw dry clay three inches long and about
two inches in diameter. The blasting acted
IN various mixtures or air, coal dust. gas.
etc, and 10 stop the course of the plug and
break 1t into dust a castiron target plate
one inch thick was placed twenty-five feet
in front. at an angle OF forty-flve degrees.
After three or four shots the inch iron
plate was penetrated by the clay plug.
weighing ~ ounces.
Movable bubbles are often seen in quartz
and other crystals, but the appearance and
disappearance of inclusions of this kind is
bit of natures magic not often observed.
An interesting experience with a cerulean-
blue sapphire is given by Mr.. W. S. Beck
man in the Microscope. This was a beauti-
full gem of nine carats but it had flaw,
and one cold morning he was astonished to
see a moving bubble In this flaw as he
picked up the stone He FASTENED away to
show the phenomenon TO a friend. He could
ind no bubble for his friend, however, and
at home he sought II again in vain, then
tried to reason that IL had in way
worked out of the stone. The search was
resumed In the evening. Turning on the
light, there again was the bubble. but it
was falling to pieces and in a few mo-
ments had disappeared. Its vanishing was
a trick of temperature. Between 50 and Sc
degrees Fahrenheit, which is the critical
point of carbonic acid when ander a pres
sure of ninety atmospheres-the bubble
changed from a liquid to an invisible gas.
In addition 20 the knowledge that is called
skill or art, explained DR.. Pye smith at
University College, Sheffield, there is an
other kind Of knowledge that is contem-
plative and theoretical, and we call this
science. The abstract sciences seem to have
arisen out OF the need of the useful arts
geometry out of measuring the rising of the
Nile, arithmetic out of counting the hosts
of Persian despot or the gains of an In
dian money lender lrigonometry out of set
ting landmarks. chemistry out of the al
chemists search after gold botany out OF
mater1a medica and anatomy out of
gerry. Amply mas the debt been repaid. At
the present time all the progress in the use
full arts is called scientific and rightly so,
for all depends upon natural science. Agri-
istry, geology and botany, navigation on
astronomy, tho working of metals on
physics and chemistry engineering on
mathematics, medicine on physiology and
If ever the art Of governing mankind is TO
be more than empirical it will rest on pro-
found knowledge Of palaeontoiogy and
neuro- physiology.
A few years ago chemical analysis was re-
lied on to determine the fitness of water for
drinking, and sufficient diluton of poisonous
matter was regarded as making it harmless.
This is changed. The problem is now looked
upon as a biological re ther than chemical
one and the purity of the water is judged
by the character of the organisms it may
contain the fact being recognized that even
the minutest possible quantity of foreign
matter-if it be a disease germ-nay be
sufficient to start an epidemic The danger
consists not in the quantity of such organ
isms but in their power of growth under
certain conditions. Typhoid fever. cholera
aid certain forms Of dysentery are the
chief diseases whose infection ii is gener-
ally admitted can live in water, but Dr. M
A. Veeder of Troy, N. z, states that dur
ing the last ten years he has maintained
that the term malaria, meaning bad air, Is
a missioner, and that diseases of this class
are very largely, If not exclusively, con-
veyed in water. Admitting this, drinking
water brings two classes of danger. Water
taken from near human habitations may
he contaminated with typhoid and dlarrhoea
AlOLt CASlCldt anu ti1oN AAOiAi VA 64h oCA @bI
undrained districts may bear the germs OF
malaria Shallow wells in alluvial soil, also
may yield ni.lartal infection. IN many To-
calities safe water can only be had by
publication. and for this an intermittent
filtration-taking advantage of a recently
discovered antagonism between what are
known as nitrifying organisms and disease
germs-may be better than sand filtration
alone, the water being allowed to stand IN
the filter until introduced ntrifying organ
isms have had time to destroy their foes
For home publication of water boiling is
most convenient. DR.. Veeder's plan is to
allow the boiled water to deposit its sedi-
ment in a stone jar, then to transfer it to
air-tight glass fruit jars. and store In q cool
cellar or an ice chest Such water is clear
and palatable, and keeps long.