MOSCHOPOULOS. RHABDAS
551
of Smyrna, arithmetician and geometer, tov c Paf3Sd, at the
instance of the most revered Master of Requests, Georgius
Chatzyces, and most easy for those who desire to study it.’
A long passage, called e/c0pacr4y tov SuktvXlkov /xirpov, deals
with a method of finger-notation, in which the fingers of each
hand held in different positions are made to represent num
bers. 1 The fingers of the left hand serve to represent all the
units and tens, those of the right all the hundreds and
thousands up to 9000; ‘for numbers above these it is neces
sary to use writing, the hands not sufficing to represent such
numbers.’ The numbers begin with the little fingers of each
hand; if we call the thumb and the fingers after it the 1st,
2nd, 3rd, 4th, and 5th fingers in the German style, the succes
sive signs may be thus described, premising that, where fingers
are not either bent or ‘ half-closed ’ {tcXivogevoL) or ‘ closed ’
(owreAAoyueroi), they are supposed to be held out straight
(e/creiroyae^oi).
(a) On the left hand :
for 1, half-close the 5th finger only;
„ 2, „ „ 4th and 5th fingers only;
„ 3, „ „ 3rd, 4th and 5th fingers only;
3rd and 4th fingers only ;
3rd finger only;
„ 7, close the 5th finger only;
„ 8, „ „ 4th and 5th fingers only;
„ 9, ,, „ 3rd, 4th and 5th fingers only.
(6) The same operations on the right hand give the thou
sands, from 1000 to 9000.
(c) 0 n the left hand:
for 10, apply the tip of the forefinger to the first joint of
the thumb so that the resulting figure resembles or;
1 A similar description occurs in the works of the Venerable Bede
(‘ De compute vel loquela digitorum forming chapter i of De temporum
ratione), where expressions are also quoted from St. Jerome (d. 420 A. D.)
as showing that he too was acquainted with the system (TheMiscellaneous
Works of the Venerable Bede, ed. J. A. Giles, vol. vi, 1843, pp. 141-3).