Richmond dispatch. [volume] (Richmond, Va.) 1884-1903, 1895-05-28
THE RICHMOND DISPATCH-TUESDAY. MAY %. 1895.

somewhat unequal length, the short arm
being arranged 20 carry a point In con-
tact with the cylinder. while the other Is
attached to the membrane. the vibrations
Of which reproduce the sound. Contrary
TO what al FIRST would seem probable. these
SOAP cylinders are declared to prove ser
yiceable for a long time in such a ma
chine, and when the surface Is covered
with Impressions IL may be washed OF
and n fresh surface exposed. The impress
sion need not be more than q thousandtn
OF an inch In depth. so that one cylinder
can be used to receive and transmit 10000
words.
slnvulsrly enough. iridium. though a
metal OF such comparative rarity, IL said
TO be a source Of no small trouble IN
the operations OF our minis. on account or
the difficulty experienced there In sepsrat-
ing II from gold bullion. Practically. "a
Is well known. this metal Is Utilized 10
some extent for making instruments OF
delicaev which require to possess the pro-
perty OF not corrodlng, and is obtained
from iridosmine, natural alloy OF iri-
dunn. osmiun1, rhodium. platinum. and
ruthenium. an extraordinary white mix
ture of rare metals. much OF II being
found in washing for gold In the beach
sands OF Oregon, and II resists the ac-
ton of all single acids. In its use for
timing gold pens, in which II Is specially
seryiceable, the grains OF II, which are
fat. like gold-dust. are picked out with
magnifying-glasses.
A writer IN one OF the mechanical jour
nails states that small iron pipes, up 70
inch IN diameter. may be bent cold and
even coiied by winding them around a
mandreI In a lathe. provided the diameter
OF the coil is at least nine or ten times
the diameter OF the pipe TO be bent; ou'
short bends in iron, brass. and lead pipe
are apt to fiatten at the bend, though TINS
is frequently prevented by Milling the pipe
with lead, the latter being melted out
on the bending being completed. He says
that a set OF bending coils can be easily
made by any machnist for use when oc-
casion demands, a separate coil being en-
ployed for each size of pipe to be operated
upon. Steel wire is wound into col
which will slide easily inside OF the pipe
to be bent-one end Of the coil tapered SC
as to allow Il to enter the pipe readily
and the other end fitted with an eve turn
ed in the end OF the wire, into this eye a
cord or chain being fastened so that the
coil may be pulled out OF the pipe. Wire
one eighth OF an inch in diameter should
be used for q bending coil for pipe
inch in diameter and for lh-inch pipes
one-fourth inch Is requisite.
The important fact occurs that caustic
alkalles should under no circumstances
be used I'm conjunction with wood fbre
fo-, even when cold and dilute, remarks
the Textile Recorder. they exert a pow
erfully detrimental effect. and a solution
containing 2 per cent. Of caustic soda
dissoives wool completely by boiling FOL
short time, while cotton IS UNAFFECTED
thereby, and this affords a simple means
of estimating the respective amount Of thu
hbres In a mixed fabric, the process con
sistng in drying portion Of the fabric
at 100 degrees c., until the weight Is con
stant-noting the weight-boiling for nv
minutes I'm a solution containing ID pei
cent. Of caustic soda; removing the cottoT
from the solution, the wool mean tim
having entirely dissolved, washing II
water, then in dilute acetic acid, finally
in water, drying and weighing. This gives
the amount OF cotton. which, subtracte'
from the original weight, shows tn
amount Of wool. Ammonia has little &C
ton on WOOL though reducing the lustr'
OF the fibre.
In Photographic art, the coloreC
DENnlluf IllNAS ny SN4bl h1Nt IVA SUM
time past attracted much attention. |
seems that the prints are developed VIII
eikonogen. and fixed in a neutral bath
without the interposition of an acid bath
then thoroughly washed. and afterwar'
treated with a solution composed OF on
half ounce OF nitrate of Lead three
fourths OF an ounce OF red prussiate o
potash, and twelve ounces Of water TIL
converts the image from black into
faint yellow, when they are again tho
roughly washed and the yellow mag
toned to different colors by means o
various solutions. Thus, for blue, Nv
| ounces perchloride OF iron and six ounce
OF water are used. and, for another blue
sometimes called black blue, the print
are treated with a weak solution OF Ter
rous sulphate: for green, one-half ounc
OF neutral chromate Of potassium, an
twelve ounces OF water. the prints bein
| washed and afterward treated like IN
| blues; for brown or red sepla, Nv
| drachms copper chloride and six ounce
| OF water the action Of this solution oein
very rapid.