The daily exchange. [volume] (Baltimore, Md.) 1858-1861, 1858-04-16
SCIEN AND ART.
lFfom We Sc1entitc Americdn


VALUABLE METALLIC PROCESSES. One of the i'm
ProVements introduced in recent years in metal
lurgy is a combination of many kinds of iron, to in
sure the good qualities of each; and another is the
auixture OF small quantities of other metals IL Is
supposed that the fuidity of Berlin cast iron, by
winch the exquistely delicate ornaments are capa-
Ole OF being produced, is due to the addition OF
a little arsenic. Maganese is found to give
closeness of grain to iron. Carbonate of zinc
gives increased maleabity to iron, and with
certain kinds it produces extraordinary toughness; if
1t be introduced into the iron of wheel rail- it
gives toughness and strength, while if anthony be
added to the surface OF the it imparts steey
hardness that qualities can be induced suitable to
the different kinds of service which each part is to
render. And 1t is remarkable that these changes
are wrought by so small ratio per cent. or
less OF the additional metal. On the other hand
the addition of one two per cent of iron to brass
IS found to produce most valuable substitute for
bell and gun metal, and SIMILAR compounds Large
guns large screws, propeller vanes, mill brasses
railway bearings, bells and other articles are now
made of a metal in which copper tin, zinc. and iron
All take part; the proportions are varied, according
as toughness, hardness, sonorous power or suscep-
tibty OF receiving polish, are required. Russian
sheet iron Is known to be superior in quality to any
article OF the kind made elsewhere; a peculiar fl
brous iron is required and this fbrous quality is
supposed to be given to the Russian iron by the pres
ence OF little phosphorus and little silica in the
ore, and by the acquisition of little carbon from
the woodfuel used in smelling.
9. ID. Seropyan, of New Haven, Conn, has Sc
cured patent in England for mode of preparing
bank notes, bills of exchange and other papers to
prevent counterfeitng by photography and its kin
dred processes, by using two more coors, which
do not reflect nor transmit, but absorb the chemical
rays OF light of which shall be applied to the
paper as to cover the surface with tint of red or
yellow shade of color, while an ink of a different
color from the surface tint shall be used for print
ing the other parts of the said surface Where this
mode OF preparing notes is observed, counterfeiting
by Photographic kindred means cannot be effect
ed; Tor SO long as the tint ground and the Wig
nettes and lettering remain together, distinct i'm
preston of the latter cannot be obtained sufficiently
clear and distinct to answer the purpose of the
countereiter because both the colors neither trans
mt nor reflect, but absorb, the chemical rays of
light.
THE LEvIATHAN.-Some idea of the immense
magnitude of this monster steamer may be formed
from the fact that the cost of completing her
Tor sea, putting on board stores, &C., and fitting
her for the trip she is expected to make to Portland
Maine, the coming summer, will amount to the
enormous amount of S600,OU0 No less than ten
anchors are required to hold her at her present
mornings each with lengths of cable from 40 to 100
fathoms All her masts are to be stayed by iron
rope standing rigging of the most massive kind
the shrouds and stays of which are so secured at
their ends through iron rings as to enable a single
sklltu man to cast loose all the fastenngs of each
mast IN five minutes, in the event of disaster,
though until the rings are opened the sides might
yield from the ship before the shrOuds would
yield.
ANOTHER AMERICAN TELEGRAPH.-There is pro-
Ject on foot at St. Petersburg for establishing
strictly overland Geographic company with North
America. The plan has been presented to the gov
eminent by Belgian engineer, and consists in car
rying telegraphic line by Siberia, and to establish
submarine communication between Canes East
and Prince of Wales then to join the lines to those
OF the United States through the territories of
Russia, and England.
Powers, THE SCULpToR.-We observe that our
distinguished countryman, Powers, has secured an
other patent in England for machine for punch
ing, stamping, or cutting metals other substan-
ces, In which the tool can be changed very quickly
and the whole machine can be taken to pieces and
re-adJusted with great expedition. Like the singu-
lar and novel formed rasps he invented few years
since, 1t appears to be simple in construction and
admirably adapted to the purposes for which it is
designed.
How TO Cool WATER.-If it is desired to cool wa
ter for drinking in weather, and ice cannot be
obtained for this purpose, let it be kept in an I'M
glazed earthenware pitcher wrapped around with
Two or three folds OF coarse cotton cloth kept con-
stanty wet. The theory of cooling water in this
manner is the absorption of heat from it, by the
evaporation of the moisture in the cotton cloth
expansion produces cold, compression heat
THE ATLANTIC TELEGRApH-Four hundred miles
OF new cable are in course of manufacture supply
the loss from the failure of the experiment last year
and 300 additional miles which it has been resolved
should be provided to allow greater lenUth of
slack than was originally contemplated. The cost
for these additional 300 miles is estimated at SS0
600. 1t is generally believed that the plan of oin-
ing the cables in mid-ocean, instead of starting
from either shore will be resorted to- Considerable
modlflcatons are being made in the machinery and
experiments are now in progress with a view of
making the machinery for paying out as nearly as
possible selfactng.
New LUBRICArING MArERIAL-M Rohrio has dis
covered means of removing the acid principles of
lat, and thus enabling it to be applied as lubrica-
tor for machinery without danger of oxydizing the
metals with which it comes in contact besides free
ing 1t from all disagreeable smell and TASTE and
rendering 1T to consistency of castor OIL 1t hard
ly coors copper, bronze brass does not run like
olive oil and other thin oils, and is much cheaper
than the ordinary lubricating material