wood, divided into two compartments by a bar running down
the middle: through this har, at right angles, are inferted.a
number o f parallel wires, and on each wire, in one compartment,
are five moveable balls, and in the other two. T heft
wires may be confidered as the afcending and defcending power?
o f a numeration table, proceeding in a tenfold proportion ; fo
that i f a ball upon any o f the wires, in the larger compartment,
be placed againit the middle bar, and called unity or one, aball
bn the wire next above it. will reprefent ten, and one on the
next one hundred ; fo, alfbya ball on the wire next below that
expreffing unity will be one-tenth, the next lower one hundredth,
and the third one fhoufandth, part o f an unit ; and the
balls on thé eorr efponding wires in the fmailer compartment
will be five, fifty, five hundred, five-tenths, five hundredths^
five thoufandths ; the value or power o f . each o f tbefe, in the
fmailer divifion, being always five times as much as o f thofe in
the larger. In the following figure, fuppofe X be affirmed as the
line o f units, the lines to the right will be integers decimally in-
creafing, and thofe to the left fractional parts decimally decreaf-
ing ; and the Swan-pan in the prefent pofition o f the balls, will
■reprefent the number 573916 -,
This
This is clearly a fyftem o f decimal arithmetic,-which, for the
eafe, fimplicity, and convenience o f its operations, it were to
be wifhed was generally adopted in Europe, inftead o f the.
endlefs ways in which the integer is differently divided in different
countries, and in the different provinces o f the fame
country. The Swan-pan would be no bad inftrument for
teaching to a blind perfon the operations o f arithmetic. Yet,
paradoxical as it may feem, thefe operations, as performed by
the Chinefe, like their written characters, require more the ex-
ercife o f the eye than o f the mind. The fimple addition or fub-
tradtion of the little balls to, or from, the middle bar, ihews at
once by their difpofition on the board the refult o f any required
combination. The invention o f it I think may fairly be attributed
to the Chinefe ; though it has been compared, how ju ftly
I cannot pretend to lay, to the Roman abacus.
It has been obferved, and perhaps with a great deal o f truth
that the arts which fupply the luxuries, the conveniencies, and
the neceffaries o f life, have derived but little advantage in the
firft inftance from the labours and fpeculations o f philofophers;
that the ingenuity o f artifts, the accidental or progreffive dif-
coveries o f common workmen, in any ,particular branch ofbufi-
nefs, have frequently afforded data, from which, b y the rea-
fonings and inveftigations o f philofophers, hints have fome-
times been ftruck out for arriving at the fame ends by a Ihorter
w a y ; that the learned are therefore more properly to be confidered
as improvers than inventors. O f this mortifying truth,
the Chinefe afford many ftrong examples in theft arts and manufactures,
and particularly in fome o f thofe operations that
have a reference to chemiftry, which cannot here be faid to
<3, 0. exift