The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1868-07-23
TESTING THE WEIGHT OF coin.

Josenh Ne gion. OF the Royal Mint, London, we
gather the following interesting lnlormsUon;
The automatic weighing machine was intro
duced at the Royal Mint by Captain Harness.
TO Mr.. Jas. NJ. Napier, the celebrated engineer,
OF York Road Lambeth, however, must be
awarded some OF the credit oil perteotlug the
mechanical Arrangement OF the apparatus. The
Bank Of ENGLAND had previously adopted an
automatic system Tor the detection aud relec.
tion OF light soyereigns and half soyereigns
and this circumstance, no doubt led to the IN.
PRODUCTION OF a similar plan at the Mint. The
Bank machines took no cOgnizaNce of too hedUy
coins; their objection only extended to those
which we're too light.
1t will be readily understood that if the
Mint authorities allowed COINS to escape which
were oboUe The legal maximum weight 1T would
tel seriously upCn the expenditure. IT. ON the
contrary, they permit ed lght pieces TO go into
the hands of the public, the latter would be de-
irauded. These exiGencles demanded more
compleXity than was required by the Bank auto
matte maChiues. The mechanical problem in
NOlyed IA the Mint requirements was solved by
MIR. Napier, and his machiue was found TO per-
form its deNCate aud onerOus functions with un-
erring eXaotitude. At present there are seven
teen OF these silent but inialnble pledges OF the
accuracy OF NelehL Of staud ard gold aud silver
coins IN the Weighing Room OF the Mint. The
automatic balances appear almost 10 be en-
dowed with the fACuty OF thought They seem
10 deliberate as 1t were, upon he character OF
each piece OF money submitted TO tner
arhitration, and TO acqult or condemn
according TO the evidence adduCed. Each
machine is placed upon u lOT bench or table
of cast lTOn, and at first glance they might
be mistaken for 50 many sgeleCun clock covered
by glass cases 10 protect tuelr "wo Ks" from
dust and humidity. iu order to, communicate
motion to then, line OF small and brightly
turned wrought iron shaiting, supported by
neat peuGants from the ceiling above, spans the
whole length Cl The apartment. The shaftng Is
placed immediately over the mGchlues, and fine
gut bands passing around pulleys descend
&c CORES spOnulug pulleys on the driving spin.
dies. The lower series of puIleys are immedi
nteiy outside the machine cases, through holes
IN which the sDiudles turn. small brass
weight lever, attached to each machine, serves
to tighten the gu, band, SO as to give motion
TO the cOlu-ecomg slides, ETC., within the
cases. Tiny rcton clutches, adjustable by the
pressure of the thumb and nngCr, allow Ot the
engagement or dlsengagement o each machine
at moment notice. In remote corner OF
the weighing room is placed the motive power.
This cons et an atmospheric engine, which
closely resembles, externally, hlgb.Dressure
steam engine, Ii has Its cylinder piston, slide
valve, governor, aud hI-"LeeL meath the
cylinder and forming the bod-plate upon which
II rests. is a vacuum ChQmOer OF considerable
area. THIS Is exhausted b. an air-pumD, and
the eXtsut Of raretaC lOu within the chamber is
controlled aud regulated Oy relief valve and
barometer gauge. When this atmospheric motor
OF the automatic machine is required to be
placed IN action, o eLOpCOcH l. turned, and
CoWmuu cation Is thus made with the air-DunD.
a stream OF ar i"ou the rooms then rushes
through bell mOuthed tube Of brass aud
presses uUon the piston OF the engine. Tue
10 airy motion follows as if ste tm we're the agent
employed o eject 1t. The ad vantage OF this
arTHuqz qzmcnt ls that Uniform rate of speed is
ohamed Tor the overhead sbaFtmg, by the in.
tcrvtn'iCu OF q strap and pulley, and so for
the automatic macline5. Without that uni.
iOImity accura Heighng would be al lmpossi-
blilty. l. has been remarked that those who
thluE twice bCtOre sOeakIug once, speak twice
the better for it, and it is certainly exact TO
remark that tue weighing balance which is
allowed due time for acting will yield far more
truthful results than that which is not. Cue of
the great principles necessary TO be observed IN
correct automatic weighing regularity of
motion, and another deliberate eness. it has
been stated that the la Of gragtatiOn is infal-
lble aud il Is so; buf it must be allowed far
play, and tIeedom i'll time 10 insure that mtalli-
b,ity. As the mind OF a judge III a Court of
Justice must, II bis decisions are to be just be
alike uusWayed by pa sion aud by prejudice, so
must the mute arblters Of Mint coins be free
from disturbing causes Of auy kind, if their con-
cIusIous are to be truthful. Having thus, as
fully as circumstances Will permit, explained
automatic weighing machines, let us return
to he patches OF CONS which have been trans.
feTred to the judicial department in which they
are placed. We Will suppose that 90 or Gu
iOlYHeeS OF sovereigns, stamped, milled, aud
apparently fitted for the business OF active life,
are about TO undergo the Enai test OF their fit
less tor duty, namely, that Of individual weight.
They are first weighed in the Quantities named,
by means OF a large and-buianCe, of which 1t
is only necessary to say That it is extremely
sensitive. The use OF this primary weighing IN
bulk is that IL may furnish a check upon the
work peope Whe are to feed the automatOrs,
and otherwise wait upon them when IN action,
whole Importation OF coins, they are forth With
distributed among the sef-actinS machines
Each of the latter is surmOunted by spout
placed at an angle, and supported by
strut. This spout or slide is the receptacle
for CONS, aud in It hey are placed IN rouleauE,
where lhey rest until the machine is
started. Tnon a small plate of steel, below the
base Of the spout, advances and reGedes at
speed OF twenty times either way per minute.
In its advancing movement it presses forward
siugle coin unLii 1t rests upon Il tiny sCale-pan,
folmmg part of q fine steel rod, which is
delcately poised and 20 adjusted as to move
the beam, or 10 be moved by it, as it may te
100 heavy or too light Above the opposite end
OF the beam depeAds another rod which, ter
mmauug IN loop OF cage at the base OF the
machine, sustans II glass eOun,erpOise weight
OF the LEGAL minimum weight OF a sovereign.
Below the cage, but not attached to it, is q
miniature "stlIrupn il which rests q piece OF
platinum WIe platinum Is pre- erred because it
ia less liable 0 Oxldation) OF the precise weight
OF the gal difference or remedy allowed as q
compensation tOr i'm per ectiOu of workmanship.
During the three seconds winch each piece OF
coin peru tted to rest upon the scale, it's fate
or fortune is decided, 1t its weight exceeds the
legal pOnt Que luta, II naturally dcpre ses the
other oud of the beam upon which IT has been
placed, and as a consequence the other end Is
raised, and with II the stIrrap and remedy wire.
This is fatal. The slide dresses forward another
candidate, aud lhis latter pushes the condemned
com Oh IT. seat. aOd takes it, place. The cuprit
fats through a Hat brass ruOe, aud is conducted
ibtO the TOO heavy" recess below the machine
there 10 await its puAi,hmCut-R return to the
CTuCble. The lowest office of he conducting
tube made to VibraIe over the three spaces O
stats oe.oN, aud tnesG lead 10 the light,
medium" =" and "beagy" compaTLmeuts, Al tae
instant The two heavy coin were dismissed into
the IL be. Lbe llWsr mouth Of the latter was held