New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1895-01-14
GETTING MORE POWER FROM COAL


SIS INSTEAD OF COMBUSTION.
In recent discussions OF the possibility OF recov-
ering more of the latent energy in coal than is now
practicable. perhaps one has offered suggestions
of greater interest and value than the German
scientist. OSWALD BY combustion. owing TO our i'm
perfect methods manage 20 capture only about
10 per cent Of the force which nature has stored
away in the fuel But great hopes have been based
the kindred chemical process. electrolysis.
Some OF the difficulties 10 be encountered in this
direction may be briefly indicated. II one partially
immerses a zinc and copper plate In a bath OF
dilute svlphuric acid and connects the dry ends OF
the pieces OF metal with a Suitable conductor. he
will find flowing through the latter electric cur
rent which will gradually diminish in intensity for
two reasons: the solution. or electrolyte, grows
weaker the acid attacks the zinc and combines
Herewith; and thin film OF hydrogen gas liberated
by chemical action. adheres to the copper and clogs
1t. The hyd. ogen results from the eecrolytc sep
aration of certain water particles into their
s,tuent gases the oxygen uniting with the zinc TO
form oxide. before the acid produce a sui
phate. The bothersome phenomenon resulting from
the behavior OF the hydrogen which Is very much
like the accumulation OF ashes in an mistaken
crate under fire. is called polarization" In
tain other forms OF batteries ways found TO get
rid OF H. But this is Of the evils to be dealt
with IN eectro.ysls. Then the electrolyie is weak
ened and needs renewal; and here we have another
Finally the zinc Is gradually destroyed burned up
in fact, tie suphate being Its ash so that thirdly
have the expense OF the fuel Zinc is a great
deal more costly than coal And that's one rea son
why II Is desirable 10 work with coal IL IT be
treated electrolytcaly. 1t IL necessary. then in
efficient method of this sort. to employ electro
lyte that will not undergo deterioration and to get
rid OF the waste products easily.
The electro-che mist. Borcher. has tried to do
this using the oxygen of the air and powdered
coal his materials. and a solution OF chloride
II copper as his eectrolyte The exact arrange
ment OF his apparatus is not described but II is
.nnounced that the electroyte remained I'M
changed: and the carbo1c acid gas resulting from
chemical combination escaped OF its own accord
After little Dr. Borcher found II advisable TO
his carbon in the form OF carbon monoxiie
gas differing from "carbonic acid gas in having
only atom Of oxygen where the latter tthc
d-oxide) has two He also discovered that various
other salts besides the chloride OF copper could be
utilized In these experiments from % % per
cent OF the theoretical energy OF the coal was
obtained in the form OF electricity, and with
out the generation OF heat. Such a result falls
short OF what nay be expected eventually, but
1T an advance upon our steam-boer practice
THE Electrical World" however. remarks that
fuel is only factor in the production OF e,ec-
tricity for light power and heating Labor and
capital must also be counted In. Getting a larger
output from the same amount OF coal. II estimates
sumner. not over 10 per cent. perhaps: so that
station managers need not think OF throwing away
their present steam-engines and dynamos. Besides
much internal 'reactance' was developed in
the apparatus OF DIR. Borcher that only a small
part Of the current was really available for ex-
ternal use. Clearly. not the immediate
eve OF a great revolution. But the objective point
which earnest gaze has been set by science
may yet be gained
In the mean time II Is well to record the rumor
that two young Scotchmen cooperating have
invented form OF battery, in which the
destruction OF the zinc Is rendered much slower
than has ever been known. and the chemicals used
are very cheap. Lord Kelvin is said to have in
vested money In the scheme. II won't do to ac-
cept this story. though. without confederation.
LATER STEPS IN COLOR PHOTOGRAPHY
IvEs's NEW LANTERN SLIDE AND DU IIAURoN's
"ANAGLYPH' AND COLoRED sPEcTAcLEs
Robert d. Gray's system of obtaining tbree nbo
tographs of the subject through screens OF
different colors was practiscd by him during tour
OF Europe last summer; and reproduction and
combination. In tandem-sllde view. were recently
attempted by him at weekly lecture in New
York City. While the re:ults are not yet all that
could be desired. his work is a valuable contrlbu-
ton to the arts OF photography and OF lecture illus
tration. and he deserves announcement 10 try to
overcome the remaining difficulties.
Mr.. Ives. the Philadelphia whose studies and
invention i'll this department OF science have ct
tracted attention on both sides OF the Atlantic re-
Gently exhibited a novelty at the exhibition OF the
New-York Society Of Amateur Photography In
Mr. Gray's method there are three separate slides.
three colo screens and triple lantern, recurring
careful adjustment In order to make the pictures
overlap precisely where they are projected But
Mr. Ives puts the proper color into each OF his
three postives (and thus gets rid of the screens)
and then superposes one picture on another In a
single slide. and hence needs only an ordinary Ian
tern. Mr.. Ives makes hts prints on sheets OF bi-
chromated gelatne. instead Of glass. and then dips
them int reu. green and blue dyes Of the right
shade and strength. When dry. they can be COM
bined as described but very nice registration is
necessary to bring the details OF picture ex-
actly over the corresponding parts OF the other
two. OF course. the gelatine sheets are firmly
bound between two thin plates Of glass. ordinary
Slide covers" II this scheme could be worked out