The Warner weekly sun. (Warner, Brown Co., Dakota [S.D.]) 1883-1885, 1885-05-08
WEIGHING COINS.
How Light Weights Are Detected at the
Bank of England.

| SAS WIZ Al ~ ONSA VA
machines for detecting light coin
ious mechanism. Three or fonr hun
dred sovereigns are laid in a Ions
brass scoop or semi-tube, of such a di'
ameter as to admit them comfortably,
and self-regulating to such an incline
that the coins gradually slide down by
their own weight on to one plate of a
little balance placed at its lower ex-
tremity. Across the face of this plate
two little bolts make alternate thrusts,
one to the right, one to the left, but
at slightly different levels. If the coin
be of full weight, the balance is held
in e~quipoSe, and the right-hand bolt,
making its thrust, pushes it off the
plate and down IN adjacent tube into
the receptacle for full-weight coin. If,
ON the other hand, the coin is ever so
little eight" the balance naturally
rises with it. The right-hand bolt
makes it's thrust as before, but this
time passes harmlessly beneath the
coin. Then comes the thrust of the
left-hand bolt, which, as we have said,
is fixed at a fractionally higher level,
and pushes the coin down a tube on
the opposite side, through which it
falls into the light-coin receptacle.
The coins thus condemned are after
ward dropped into another machine,
which defaces them by a cut half way
across their diameter, at the rate of
200 a minute. The weighing machines,
of which there are sixteen, are actuated
by a small atmospheric engine in n
corner of the room, the only manual
assistance required being to keep them
supplied with coins. 1t is said that
60, 900 sovereigns and half-sOvereigns
can be weighed here in a single day.
The weighing-machine in question is
the invention of Mr.. Cotton, a former
governor of the bank, and among
scientific men is regarded as one of
the most striking achievements of
practical mechanics.
In the bullion department we find
another weighing machine of a differ
ent character, but in its way equally
remarkable. 1t is the first of its kind,
having been designed specially for the
bank by Mr.. James Murdoch Napier,
by whom it has been patented. 1t is
used for the purpose of weighing bull
lion, which is purchased in this de-
partment. Gold is brought in bars of
about 8 inches long, 3 wide and l inch
thick. A bar of gold of these dimen-
sions will weigh about 200 ounces, and
is worth, if pure, about fS0O. Each
bar when brought in is accompanied
by a memorandum of its weight. The
question of quality is determined by
the process of assaying; the weight is
checked by means of the weighing
machine we have referred to. This
takes the form of an extremely mas
sive pair Of scales, working on a beam
of immense strength and solidity, and
is based, so as to be absolutely rigid,
on a solid bed of concrete. The whole
stands about S feet high by 3 wide,
and is inclosed in an air-tight plate
glass case, q sash in which is raised
when it is desired to use the machine.
The two sides of the scales are each
kept permanently loaded, the one
with a single weight of $50 ounces, the
other with a number of weights of va
rious sizes to the same amount. When
it is desired to test the weight of a bar
OF gold, weights to the amount stated
in the corresponding memorandum,
less half an ounce are removed from
the latter scale, and the bar of gold
substituted 10 their place. Up TO this
point the beam of the scale is kept
perfectly horizontal, being maintained
in that position by a mechanical brake;
bat now a stud is pressed, and by
means of delicate machinery, actuated
by water-power, the beam IS released.
If the weight of the bar has been cor
rectly stated in the memorandum, the
scale which holds it should be exactly
half an ounce in excess. This or any
less excess of weight over the $50
ounces in the opposite scale is instant.
ly registered by the machine, a pointer
travelling round a dial until it indicates
the proper amount The function of
the machine, however, is limited to
weighing half an ounce only. If the
discrepancy between the two scales
as loaded is greater than this, or If,
on the other hand, the bar of gold is
more than halt an ounce less than the
amount stated In the memorandum,
an electric bell rings by way of warn
ing, the pointer travels right round
the dial. and returns to zero. So deli
cate is the adjustment that the weight
Of halt q penny postage stamp-some-
what less than half a grain-will set
the hand in motion and be recorded
on the dial.
The stock of gold in the bullion
vault varies from e. 0 % to f IS, Gee Geo.
600. The bars are laid side by side
on small tiat trucks or barrows carry
ing 100 bars each. In a glass case in
the vault is seer a portion of the war
indemnity paid by King Coffee, Of
Ashantee, consisting of gold orna.
ments, a little short of standard fine.
ness.- Mdnabers's Journal