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the head indicate the figures of the Quotient. —
The Quotient 4 just found must, therefore, he taken
down. After haying subtracted the number 39592
from 41868 we add to the remaining 2276 the
next figure of the Dividend, 5, and seek then
for the number 22765, thus obtained, the Product
next to it in size, which proves to be 19796,
in column 2. This figure 2 is added to the
Quotient 4, set down first, and the process then
continued in the same order, which will yet pro
duce, as third and last figure of the Quotient, the
number *3, and with that we shall have the re
quired Quotient 423.
Written down the example will assume the
following form:
39592
22765
19796
29694
29694
The Division on the Russian abacus is to be
effected in the following manner. The Dividend,
for instance, 4,186,854, is counted on the abacus,
and the Products 39592, 19796, and 29694, are
subtracted from it in the same order as in the
written calculation. The figures of the Quotient
thus produced, are thrown out, one under another,
on the empty bar of the abacus.
From the above solution of the question it is
evident, that the Quotient is contained in the
Tables ready-made, and that a simple process of
subtracting only is needed to complete the calcu
lation.
On the whole, the object of these Tables is
to reduce Multiplication to mere Addition, and
Division, to Subtraction.
Note.
The author, of these Tables who has spared neither
labour, nor money, to make them as practical and useful
as possible, and thereby to introduce them to general use,
begs to draw the reader’s attention especially to the follow
ing hints which will greatly facilitate the use of the
Tables :
1. Each Table contains 99 numbers which, in system-
order, fill up the middle column. Thus we find in
the first Table the numbers from 1 to 99,
„ second „ „ „ , „ 101 „ 199,
„ third „ „ „ „ 201 „ 299
and so on.
By this uniform arrangement of the Tables, the
searching and finding of any required number will be
greatly facilitated.
2. On the margin of each leaf the number of the
hundreds is printed with Avhich the left hand Table begins;
so that by cutting off the lower blank part of the margin
an index will be obtained by which it is possible to find
out at once the page containing the required number, with
out being obliged to turn over the leaves in search for it.
3. The prime numbers (Multiplicand, or Divisor) are
contained in the middle column, just between the numbers
of five and six-fold value. By this arrangement an easy
and quick survey of the Tables is afforded, the eye getting
soon accustomed to look for numbers of from two to five
fold value on the left, and for those of from six to nine
fold value on the right hand of the middle column.
4. The Products in the Tables do not always appear
in their complete form; but whilst one lino shows the
Product in its entireness, the next shows only the increase
in the units and tens, omitting the hundreds and thou
sands. In the next following line, however, the Product
is again printed in its complete form, and so on alternately.
In this way the dazzling effect of long rows of compact
numbers is lessened. It prevents the eye from becoming
weary, or wandering into a wrong line.
16
18
20
22
24
26
28
30
32
34
36
38
40
42
44
46
48
50
52
64
56
58
60
62
64
66
68
70
72
74
76
78
80
82
84
86
88
90
92
94
96
98
100
102
4