The sun. [volume] (New York [N.Y.]) 1833-1916, 1896-11-01
porrs ON sc1BNoB AND 1xD Us1nr,

Investigation shown the peculiar fact that the
deepest part Of the Mediterranean sea, contrary to
what might be expected under apparent circum.
stances, appears intensely blue. This has been
supposed TO be caused by minute particles held in
suspension. but recent experiments made by Prof.
Spring at Liege suggest a different explanation OF
no interesting q phenomenon. He has found
that warmer currents passing through pure water
interrupt its transparency, even when the differ.
ence OF temperature Is but very slight. Such cur.
rents may cause deep water TO appear blue by re-.
fecting light back from its depths through the
transparent layers above. This, 1t is suggested, ex.
plain, the fact that fresh water lakes arc moro
transparent in winter than in summer. because In
winter currents of heated water are not travers.
ing them. Even the shadow of a mountain falling
on a lake may Increase the transparency of this
water by cooling the surface. The we'll known the.
DRY OF scientists concerning this nnttor has been
that pure water appears blue when light is trans.
mitted through a certain thickness OF 1t, and that.
when opaque particles are suspended In It the hue
OF the water ia ereenish, hut while pure water
looks blue whom light passes freely through II.
yet when It is in a deep receptacle, like the basin
of a lake, or the ocean, II ought to absorb oil the
light and look black.
An apparatus by which an engineer may test or
determine the quality and adaptation of the coal
he receives ia described in the Boston journal Of
Commerce. Tho test Is not intended to be an anal
ysis, but principally to show the amount of nxcd
carbon in the coal and the percentage of ash. As
each car load of coal is received. samples are taken
from twenty or moro parts OF the car, tn oroughiy
mixed and quartered. each quarter being also mixed
and quarterod until the sample is obtained; this
sample Is then carefully weighed, tho volatile mat
ter driven OF, weighed again. and the carbon con-
sumcd, and the ash weighed. This estimate Is i'm
portant in guarding against the use OF coal having
an undue percentage OF ash. The various Goals
uinar In tha pprranfaVa of a which tbev contain
some Cumberland. Goals having from twelve to
fourteen per cent. of ash. while a good New River
will have MS low as three or four per cent. Thus.
though the Goals may look alike to tho average
engineer, the heat value characterlzlng them is ten
per cent. greater in one description than the other,
and, asccrtainlng this, an important saving In the
cost of fuel may result.
1t has commonly been estimated that green wood.
when cut down, contains about forty 1--WE per cent.
of Its weight in moisture, but in the forests of cen.
trail Europe wood cut down In winter is said to
hold more than forty per cent. of water at the end
of the following summer. Kept for several years
in a dry place, wood retains from fifteen to twenty
per cent. OF water, while that which has beon
thoroughly dosiccated will, when exposed to mir
under ordinary circumstances, absorb i've per cent.
OF water in the nrst three days, and will continue
to absorb 1t until It reaches from fourteen to ak.
teen per cent. as a normal standard-the amount
nuctuating above and below this standard accord.
ing to the state of the atmosphere. 1t has been
found that, by exposing green wood to a tempera.
ture OF 2ia degrees. F., the loss of weight equslied
forty five pr cent; and, further, on exposing
small prisms Of wood one. half inch square and
eight inches long, cut out OF btlcts that had been
stored for two years, to tho action Of superheated
steam for two hours, their loss OF weight was
found to be from fifteen To forty i've per cent, ac-
cordins to the temperature OF the steam.
Co.,. ...... ...= a. IL, . -
given in a recent report of the Boston Mutual Fire
Insurance Company, and are believed to indicate
the important relation Of that material TO nre.
proof work. An experimental test was mad. with
an ordinary brick structure OF nine feet high, pro.
vided on one side with a wire glass roof. and Of
roushened glass on the other, side windows. and a
glass door with wooden frames lined with tin; and
this building was filled with rosin saturated wood
To . height OF six feet. on firing, the ordinary
Tlass cracked and fell at once. while the wired glass
remained, Notwithstanding the heat was so great as
to crack the walls OF the building. The theory of
such glass standlng the heat in this manner is said
TO pe that the glass, under the nrst influence OF the
heat, cracks, but is held In place by the wires. but,
us the Leaf increases. the glass becomes fused
agalng at q lower temperature than the wire. and
being q poor conductor of heat, such glass and the
wire protect each other.
The peculiar suostance.known in textile industries
as Prussianblue. 30 largely used as q bleacher's and
nnisher's shading. is a singular combination Of iron,
carbon, ana nitrogen; It has a nne, deep, greenish-
blue color, some makes tending to a more violet
tone than others, and. when well made, the dry color
has q bronzy lusrre. The best variety goes by the name
OF Chinese blue, and this. when ground into a paste
with water, mixes fairly easily with that vehicle
and imparts TO It q fine blue color: there is another
variety also, sold as soluble blue. which dissolves
freely in water. aud Is considered the hest for nm
ishers' use. In its chemical characteristics. the
Prussian blue, whatever its form, is unaffected by
acids. and. what is of much Importance, is not
acted upon by chlorina, so that any traces of chem
&c acid which may be left in the cloth do not dis
charge the color, q, is the case II ultramartne be
employed, nor has neat any effect, while It is also
gu lite fast to light and air. The only agent or
agents which have any action on Prussian blue are
said to be soda and the alkalies or alkaline sub
stances like soap, soluble oil. or borax, these tend.
ing TO create q brown.
Chemical ingenuity is now successfully applied to
the creation OF an attractive substitute for pearl.
In this strange art. nitro.cellulose, dissolved In al
cohol and ether. or In soda or potash soluble glass,
is spread over a surface Of wood, paper, glass, por.
celain, or metal, and. the solvent being allowed TO
evapornte, the MIN remaining has the beautiful APP
pcarance OF mother of.pearl. The desirable pro.
portions for this purpose are named as follows
One part OF nitro -celluiose, seventy eight parts al.
cohol CT ninety to ono hundred per cent. and
twenty one parts ether. with soluble glass as sol.
vent, ten parts of this to ninety parts of water are
employed. The nitro-cellulose may be pure or
crude, or in different stages OF nitrincation. as sun
cotton, &C; ethyl or methyl alcohol and sulphurio
or acetic ether are serviceable. and the degree OF
concentration of the nitro, cellulose may be varied
within certain limits. those variations produ ling, of
course. different results.
by = comparison of the spectrum" or lines OBJ
served in sunlight with the spectra, of substances
found on earth, Kirchhon has earned the renown
OF having demonstrated that q large number OF ter.
restrial elements exist In the sun, among which are
such well known substances as hydrogen, iron,
nickel. zinc, copper. lead. and aluIninum-thH ex'
traordinary fact appearing, however, remarks q
writer In Chambers journal, that oxygen, which
Is so lavishly prevalent on earth, seems to have
deserted the sun altogether, none being observable
in that luninary. Concerning this Interesting
point, It is asserted that for an element TO attest
its presence in the spectroscope, It must not only
be present in considerable relative quantity and in