The Middlebury register. [volume] (Middlebury, Vt.) 1850-1882, 1859-04-13
Manufacture of Needles.

Manufacture of Needles.
Needles, to prove of the finest quality
require to be manufactured of the very
best steel wire that is produced. A coil o.
the wire, in its soft state, is cut by large
pair of shears. into lengths of four or five
inches, The bundles of length are 6rst tc
be made quite straight, which Is done by
putting ring over each end, laying tht
bundle on an iron table, and rolling il
backward and forward by fat piece o.
iron placed upon it. The pieces, cut into
the proper lengths for needles, are next
pointed, which is done by the operator
holding two or three dozen at time upon
a dry grinding stone, each wiro revolving
while in contact with the stone.
The eye Of the needle is generally per.
forated by female operators the end Of
the wire is aattened by the blow of ham.
mer, and the perforation is made by a
steel punch, the grove where the eye is
placed being made by particular file.
The needles, when perforated, again re.
quire Strengthening by process similar to
that already described. They are next
hardened. as hitherto the steel has been
in soft state. For this purpose, several
thousand of them are placed in cast.iron
receptacle in which they are covered with
ashes to prevent oxidation, heated to a
cherry red, and afterward tempered to a
blue color, Again they require straight.
ening, and then are secured bright this
is performed by collecting them in regu.
lar tiers in strong cloth, each tier being
separated by some fine emery, oil, and
soft'soap. The parcel, being then tied
round with strings, is placed under a
loaded box like common mangle, by the
motion Of which, backward and forward,
for two or three days,the needles are rub.
bed against one another, and the whole
come out clean and bright. Lastly. they
are picked and sorted, the heads all one
way, and ready for sale.
TIE DIAPHRAGM STEAM GENERATOR.
The principle upon which this steam
generator, invented BY French engineer,
il ba.ed. is that bodies evaporate only
from their surfaces. This being received
as fact, it must necessarily follow, that
in the construction Of steam boilers, either
the evaporating surface Of metal should
be expanded to its utmost limit, or the
water should be so divided, and its evap.
Grating surfaces BE- so multiplied, as to
arrive at the same end, OF obtaining the
greatest amount Of steam by the expendi.
ture Of the least amount of fuel. The
steam generator is described as consisting
Of vertical cylinder of wrought iron,
twenty-five inches high by about twelve
and half inches diameter the base ter.
minating in hemispherioal end, and the
upper part closed by curved lid, upon
which are attached the usual steam and
!afety valves, feed. steam, and other pipes
&c. The interior contains q series of di.
aphraems Of wrought iron, pierced with a
number Of fine holes and having alternate.
ly convex and concave surfaces. They
are suspended by three iron rods, at given
distances apart, in such manner as not
to be in contact with the heated exterior,
or shell of the boiler.
When any water is admitted through
the feed pipe, it falls upon the upper or
convex disc, which has q tendency to
spread it to the periphery, the largest
quantity falling through the pertorations
in the shape of globules; the second dia.
phragm being concave, tends to direct the
fluid from the circumference to the centre,
and SO on, until, il any fluid reaches the
body of the cylinder, it mingles with a
thin film of water, in high state of eb.
ullition, that being the hottest part of the
boiler. 1t appears, however, that in its
transit through these diaphragms,the water
Is SO divided, that, exposing very large
surface to the caloric, it is transformed
into steam with great rapidity. and with
great economy of fuel. The consumption
Of coal is stated to be very small, 7s9
pounds Of water having been converted
into steam by 1872 pounds of coal in ninc
hours, under pressure Of ten atmos.
phsrss.