If we must die--let it not be like hogs Hunted and penned in an inglorious spot, While round us bark the mad and hungry dogs, Making their mock at our accursed lot. If we must die--oh, let us nobly die, So that our precious blood may not be s... Read more of If We Must Die at Martin Luther King.caInformational Site Network Informational
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Manufacturing

On The Causes And Consequences Of Large Factories
263. On examining the analysis which has been given in chapt...

On Combinations Of Masters Against The Public
376. A species of combination occasionally takes place among...

Of Copying
82. The two last-mentioned sources of excellence in the work ...

On The Duration Of Machinery
340. The time during which a machine will continue to perform...

Of Copying By Stamping
128. This mode of copying is extensively employed in the art...

Of Price As Measured By Money
201. The money price at which an article sells furnishes us ...

Economy Of The Materials Employed
77. The precision with which all operations by machinery are ...

Enquiries Previous To Commencing Any Manufactory
298. There are many enquiries which ought always to be made ...

Regulating Power
27. Uniformity and steadiness in the rate at which machinery ...

Of Money As A Medium Of Exchange
166. In the earlier stages of societies the interchange of t...

Registering Operations
65. One great advantage which we may derive from machinery is...

Of Raw Materials
210. Although the cost of any article may be reduced in its ...

On The Influence Of Durability On Price
197. Having now considered the circumstances that modify what...

Printing From Surface
91. This second department of printing is of more frequent a...

Accumulating Power
20. Whenever the work to be done requires more force for its ...

On The Effect Of Machinery In Reducing The Demand For Labour
404. One of the objections most frequently urged against mac...

On Contriving Machinery
318. The power of inventing mechanical contrivances, and of ...

Of Copying By Moulding
112. This method of producing multitudes of individuals havi...

On The Method Of Observing Manufacturies
160. Having now reviewed the mechanical principles which reg...

Exerting Forces Too Great For Human Power And Executing Operations Too Delicate For Human Touch
56. It requires some skill and a considerable apparatus to e...



Of Copying By Stamping








128. This mode of copying is extensively employed in the
arts. It is generally executed by means of large presses worked
with a screw and heavy flywheel. The materials on which the
copies are impressed are most frequently metals, and the process
is sometimes executed when they are hot, and in one case when the
metal is in a state between solidity and fluidity.

129. Coins and medals. The whole of the coins which circulate
as money are produced by this mode of copying. The screw presses
are either worked by manual labour, by water, or by steam power.
The mint which was sent a few years since to Calcutta was capable
of coining 200,000 pieces a day. Medals, which usually have their
figures in higher relief than coins, are produced by similar
means; but a single blow is rarely sufficient to bring them to
perfection, and the compression of the metal which arises from
the first blow renders it too hard to receive many subsequent
blows without injury to the die. It is therefore, after being
struck, removed to a furnace, in which it is carefully heated
red-hot and annealed, after which operation it is again placed
between the dies, and receives additional blows. For medals, on
which the figures are very prominent, these processes must be
repeated many times. One of the largest medals hitherto struck
underwent them nearly a hundred times before it was completed.

130. Ornaments for military accoutrements, and furniture.
These are usually of brass, and are stamped up out of solid or
sheet brass by placing it between dies, and allowing a heavy
weight to drop upon the upper die from a height of from five to
fifteen feet.

131. Buttons and nail heads. Buttons embossed with crests or
other devices are produced by the same means; and some of those
which are plain receive their hemispherical form from the dies in
which they are struck. The heads of several kinds of nails which
are portions of spheres, or polyhedrons, are also formed by these
means.

132. Of a process for copying, called in France clichee. This
curious method of copying by stamping is applied to medals, and
in some cases to forming stereotype plates. There exists a range
of temperature previous to the melting point of several of the
alloys of lead, tin, and antimony, in which the compound is
neither solid, nor yet fluid. In this kind of pasty state it is
placed in a box under a die, which descends upon it with
considerable force. The blow drives the metal into the finest
lines of the die, and the coldness of the latter immediately
solidifies the whole mass. A quantity of the half-melted metal is
scattered in all directions by the blow, and is retained by the
sides of the box in which the process is carried on. The work
thus produced is admirable for its sharpness, but has not the
finished form of a piece just leaving the coining-press: the
sides are ragged, and it must be trimmed, and its thickness
equalized in the lathe.





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