508 
NATURE 
[Marcu 31, 1904 
Alexandra parrakeet, discovered during the Stuart 
Expedition into central Australia in 1862; the paradise 
parrakeet, classed with the golden-shouldered parra- 
lkeet as the most lovely of all the Australian parrakeets ; 
and the splendid parrakeet the wonderful colours of 
which, as well as those of the species last mentioned, 
are displayed on two of the plates. 
It has been the aim of the author to make the pre- 
sent book a complete monograph of the imported 
species of parrakeets. New species may be expected 
to arrive from time to time. For instance, when the 
first part of the worl was issued no living specimen of 
the varied lorikeet (Ptilosclera versicolor) had ever been 
known in this country, but a few months later a few 
pairs reached London, and this species has accordingly 
been included (with a coloured plate) in the appendix, 
in which additional information respecting several 
other parrakeets is to be found. OF Vea: 
MULTIPLICATION TABLE. 
Table of Multiplication, Division and Proportion for 
the Ready Calculation of Quantities and Costs, 
Estimates, Invoice Prices, Interests and Discounts, 
Weights and Strengths, Wages and Wage Pre- 
miums. By Robert H. Smith, M.I.M.E., &c. 
(Westminster: Archibald Constable and Co:, tds; 
1903.) Price 6s. net. 
HIS consists simply of a gigantic multiplication 
table for every figure up to 100 times 160, there 
being 100 horizontal lines of products arranged in 160 
vertical columns on a sheet 5 feet long and 113 inches 
wide. The sheet is mounted like a map upon canvas, 
so as to open at any part of the length and exhibit 
two pages, each page containing 10 vertical columns 
indexed right and left with every roth number up to 
too. To guide the eye wider spacing is provided at 
every fifth line and column, and still wider at every 
tenth, as in logarithm tables. The index numbers 
are equivalent to a repetition of the first column on 
every page, so that any line up to the tooth can at 
once be found. As in any other multiplication table, 
the figure found at any place is the product of the first 
figure on the line and the top figure of the column on 
which it is found. 
On the back of the sheet are a corresponding series 
of pages on which Prof. Smith has explained how the 
table may be used for all the purposes described in 
the title. : 
If two numbers have to be multiplied together the 
product can, of course, be read directly if they do not 
exceed 100 and 160, but if that was all the table was 
for, even though it is well arranged, it would hardly 
be worth getting out of its place. If only one of the 
figures exceeds these by not more than two digits, it 
may be broken up into two parts, e.g. 3781 into 3700 
and 81, and the two partial products read, preferably 
in a single column when that is possible, and mentally 
added. If both factors exceed these amounts then four 
partial products have to be found, and two columns 
must be employed, which may be on different pages. 
NO. 1796, VOL. 69] 
This necessitates writing down the four partial pro- 
ducts of probably four digits each, and taking care 
that the units place is properly placed in each. Then 
on adding, the product is found exact, of course to the 
last figure. It is not worth while in this notice to 
refer to rules or practice as to placing the decimal 
point if the factors contain decimal figures. 
Division, of course, is performed by finding the 
quotient in the body of the table on the line or column 
of which the first figure is the deviser. Then the 
quotient will be the first figure of the column or line. 
This is only possible when the dividend is an exact 
product of two numbers not exceeding 100 and 160. 
Of course, in practice it never is, and then interpolation 
is necessary. Prof. Smith gives two methods. 
Where, however, both the diviser and quotient exceed 
too and 160 the double interpolation necessary seems 
to the writer to involve so much trouble, and to provide 
such opportunity for mistakes, that he would prefer 
to perform the operation with a pencil and paper in 
the usual way of the school if slide rules, logarithm 
tables, or calculating machines were not sufficient or 
available. 
Simple proportion can, of course, be performed where 
the four quantities are all actually existing in the 
table by direct inspection, but again, in practice they 
never would be, and interpolation, either single or 
double, would be necessary. 
The other processes described in the title which 
involve one or other of these operations are explained 
in the text on the back. It might very well be that 
for certain classes of calculation or of office worl: 
where the computer or clerk had the same kind of 
thing to do indefinitely, the table would afford the 
readiest means of finding an exact result, but for 
general use by people who could not for want of 
practice be quite adept, it is a question whether the 
constantly recurring interpolation complication would 
not give more trouble than direct arithmetic, besides 
leading to endless mistakes. C. V. Bt 
THE ZOOLOGICAL RECORD FOR too2. 
The Zoological Record, vol. xxxix., relating chiefly to 
the Year 1902. Edited by D. Sharp. (London: 
Zoological Society, 1903.) 
A LTHOUGH on the title-page this volume, which 
4 slightly exceeds its predecessor in bulk, bears the 
date 1903, as a matter of fact it was not in the hands 
of the public until the beginning of the present year. 
This slight delay, as the editor informs us, is more 
than accounted for by certain unexpected changes in 
the staff of recorders, notably the loss of the services 
of Prof. J. A. Thomson, who has felt himself com- 
pelled to relinquish the compilation of that very im- 
portant section of the undertaking entitled ‘‘ General 
Subjects.’’ His place, apparently at short notice, has 
been taken by the editor, who, in addition, is respon- 
sible for the insects, as well as for the general super- 
vision of the whole text, and must therefore have had 
very hard work to complete his task so nearly within 
the appointed time-limit. The other contributors the 
