Amador ledger. (Jackson, Amador County, Calif.) 1875-19??, 1909-04-16

In the ancient art of damaskeening,
in which Damascus excelled 10 the
thirteenth century, surface of
bronze or iron was engraved with
lines or figures, and threads of silver
or gold we're pounded into the design
with a mallet. Attempts have been
made TO produce the same ornamental
inlaying by some cheaper method.
The latest process is that of Sherard
Cowper Coles, the British metal
lurgist, who coats the object to be
decorated with a protective COM
position, and in this cuts out the
design. Placed in an iron box, in
which it is surrounded with filings
OF the ornamenting metal, the object
is then heated to the proper tenn
perature. The metal deposited in
the design forms a firmly adheling
alloy with the metal of the object,
and the effect is very artistic. Several
inlaying metals may be nsed, with a
separate heating to volatilize and de-
posit each one.
Within the last score of years
several experimental induction coils
OF large size have been built, the
latest, hy an American maker. being
the largest. using direct current with
a mechanically driven circuit breaker.
Its primary core is 6 feet long by 4
inches in diameter, weighing 30
pounds. The primary winding is 10U
pounds of No. 6 L.. rs. gauge magnet
wire, in two layers; and the second
airy winding IS made up of 2S4 seper-
ate coils of very fine wire, which has
total length of 1873 miles and a
weight of 213 pounds. The circuit
breaker ls drum one foot in dia
meter, carrying 40 semi-circular
copper bars or brushes, driven by a
small direct cure motor. On a
110-volt direct current, using 20
amperes, the coil yields a spark so
inches long. the voltage necessary to
bridge such gap being estimated at
loo. 900 volts.
About 10 grains of prussic acid per
quart has been found by an Edln-
burgh chemist in the water taken
from gas meter, indicating that the
domestic gas supply must contain an
appreclable quantity of this powerful
poison.
The change that. decade has
wrought In the conception of atoms
and molecules is not easily grasped.
Attempting to make it more clear in
late Royal Institution lecture, Sir
j. j. Thomson pointed out that
radIum, representing the greatest con.
centration of power known, breaks up
with the emission of million times
as much energy as Is produced by the
combination of an equal weight of
oxygen and hydrogen. The corpuscles
or atoms of helium thrown off move
with n tenth of the velocity of light
or about $1,000 miles a second. A
ship under the fire of Dreadoughts
would be exposed to mere child's
play as compared with the lombard
ment of an atom by these particles;
and some idea of tue condition cf a
gas under the action of radium can
be had by imagining town lombard
ed by shots as large as houses and
m ~ nj n Thousand
great velocity as any proiectile ever
shot from cannon. 10 account for
this amazing power is one of the most
interesting of problems.
Many unsuccessful attempts to pro-
duce a non -inilammable celluloid
have caused new substances OF the
kind to be received with skeptiuism,
but it Is claimed that the cellite Of
DR.. A. Eichengrun, now made at
Dusseldorf, Germany, has withstood
tests proving it to be a cheap and
useful material. Celluloid is a mix
ture of collodion cotton, nitro
cellulose less highly nItrated than
gun cotton, with camphor and sn't-
able coloriug matters. In celtic the
nitro -cellulose is replaced by an
acety l-cellnlose, made with acotic
acid instead of nitric acid, and
variety is given to the product by
substituting different artificial cam
phors for ordinary camphor. Cellite
is thus made soft, hard, elastic or
flexible. 1t 10 burning, with
mono of tho explosive combustibility
of cellulold, and can be used instead
of glass. gelatin, leather, paper and
Uarioue fahrios mr. "a n wafer. proof