Mar. 6] PROCEEDINGS. [1894.units, tens, hundreds and thousandswould each be dealt with
separately; this is of course the same as our modern method,except
ing that ourmultiplication tablereaches to 1 2, owing perhaps to
the duodecimal basisof our metrology.
Multiplicationby other numbersthan2, 5 and 10 was performed
simplyby repeated doublingandthenadding.
For instance—
" Calculate 9 to 6 times " (multiply 9 by 6) :
1 = 9
(double) 2 = 18/
(double2) 4 = 36 /
(add 2 and 4) 6 — 54 (answer 54).
A dash / marked the numbers to be added together.
Divisionwas accomplishedby converting the question intoa
multiplication sumof the same typeas the preceding, the divisor
beingmultiplieduntilthe dividend wasreached. Theanswer of
coursewas the number of times the divisor was so multiplied.
(Tobe continued.)173