New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1856-01-10

thus producing degree of beat at the point OF com
mipglng which had been before unattainable except
by the voltaic battery Such solids would not burn
in the fame Of this "OIyhydrogen blow-pipe' became
NOS. intensely brilliant; and the doctor found in per-
fectlv unslacked lime material exceedingly luminous
when thus heated. Sometime m 1926 Lieut. Drum
mond of Scotland employed this light VARIOUS hills
in coast survey of ireland, and thus enabled to
take their bearings with minute accuracy forty miles
distant The light, thus associated with the name of
Drummond due entirely 10 the heat Of the lime,
as no combustion Of that material is observed. II
liable, however to scale off under the action of the
heat and sometimes 20 crack across. BY one or the
other of these affections the ball IS usually destroyed IN
perod VARYING from three minutes 10 half an hour The
extraordinary concentration of this light, by ehsbng
il 10 be- brought with accuracy into the focus Of sua
bic mirror and thus throw all the light at viii in any
given direction contributes in high degree 10 the ex-
,raordnary result; and its compactness aud strength
early attracted the attention of the Lighthouse Boards
both Of Great Britain and France but the instability
of the material and the expense of the oxygen required
induced report decidedly adverse to its employment
About the year ls42 Dr. Lardner visited this country
and in connection with Prof. Robert Grant of this
city. gave illustrations of this light in series of lee
lures in our principal cities In the course OF an expe-
rience thus commenced Prof Grant has successfully
developed improvements which, under this far-reach-
ing apparatus are not only practicable and easily man
AGED but considerably cheaper both in first cost and
maintenance than any other strong light now in use
To this single individual has been due, believe,
all the notorety which this light has obtained in this
country. That on Barnum's Museum, which scorched
the eye-balls of all Broadway that on Grace Church,
the greatest strength Of which passed over the houses
aud whtened the sails in the haibor that on the front
of the Library at Washington, which whitewashed
Pennsvlva1ia avenue; and the revolving light on the
IattinO Tower in the Summer of 81, which at inter
walls cast distinct shadow on Staten Island, with
host OF others were all originally set up by his hands,
and we make this bIefno in the hope Of attracting
10 his improvements the attention they deserve.
Prof G's improvements for lighthouses are three
fold First the discovery and application of lime
which will withstand the blOwpipe heat second, the
DEVELOPMENT Of oxygen at moderate cost and third,
the construction of system OF signals by which the
light is shown and suppressed at such intervals that
any given number corresponding to the number OF a
lighthouse on the chart may be perpetuaHy and
plainly teegraphed to the lookout on every vessel
within an area of some five thousand square miles.
The lime is free from silica or magnesia-n shoft Is
nearly pure oxyd of calcium, and, as burned by the
Professor is free from any ncipient fractures.
cylinder ii inches diameter and inches long,
employed in the experimental lighthouse on the Latt-
inc Tower was used thirty-six hours, and the mate
rial we are assured has failed during period
equal to the longest nights in this latitude. The gases
are reserved during tie periods OF darkness and costs
by the present expensive processes about 81 per night
but by his method of decomposng the nitrate OF soda
in contact with sand forming scate of soda the cost
can be reduced to about rs cents per night for light
equal to 5000 Argand burners. The amount OF oil
consumed in our present irst-cass Fresnel lights is
about coo gallons per annum.
The method of signaling numbers is now rightly
exhibited by model lighthouse in the reading room
of the AstorHouse, and may be readily understood
by the most unettered seaman. The light is shown
once and then suppressed for ten seconds next shown
twice with an interval of about four seconds and then
suppressed for half-minute. These flashes, first
once and then twice indicate the number ~, and any
other desired may be signaled by simply changing a
cam in the clock-work. We consider the light and
the means of displaying it sufficiently perfected to de-
serve the immediate attention of Congress. Its appi-
cation for sea purposes must evidently precede its in
PRODUCTION for locomotive headlights or any other
minor uses.
IMPROVEMENT IN FIRE-PRooF SAFEs-Mr. W. H.
Batter Of this city has recently presented and intro
duced an improvement in the manufacture Of portable
safes. which would seem TO be of those steps in
practical science far more rare than combinations
of machinery The art Of making safes for the storage
of books and other valuables has been greatly i'm
proved within a few year., and this final invention by
Mr. b. seems to leave little to be desired We will
endeavor briefly to strip the whole subject of some of
the mystery and magic with which it is too much
surrounded.
No perfect non-conductor Of heat has been yet ds.
covered; STILL good safe four inches thick will pre-
serve papers for days among the ruins of an extensive
fire. In the late great trial near the NewYork Crystal
Palace in 1852 safe was kept red hst for twenty
two, and nearly 80 for twenty-fOur hours, but pro-
served the woodwork and old books within. This
effect was due to the water contained in its walls and
from this alone, in connection with certain amount
of non-conducting and steamconfning powers, is OBJ
tanned the extraordinary property typihed by the
names of fabulous ire-eating and Misunderstanding
animals 1t may surprise many to learn that the port
able safe Is another example Of the universal power OF
steam yet such is literally the fact. The efficacy OF
these boxes far as reproof qualities are concerned
depends mainly and almost entirely upon the water Of
their composition which changes to steam when heat
il applied and thus renders latent and disspates the
caoric which would otherwise penetrate the walls and
consume the contents.
The first portable Safes were of stout plank covered
with sheet IRON A great advance was the substitu-
ton of plaster for the wood, and this Is due to Mr.
Daniel Fitzgerald of this city, who sold his invention
since named " the Salamsnder;" and, although one OF
the most ingenious our country affords, Is now
struggling in comparative poverty in our midst Plas-