REVIEWS. 
75 
lowest depths of an all but defunct philosophic speculation. We are more 
surprised at Messrs. Longmans issuing such a work than we are at finding 
the author’s portrait forming the frontispiece. 
TABLES OF LOGARITHMS * 
T HIS is a small work, but calculated to be exceedingly useful to com- 
puters, and more particularly to nautical men and surveyors. We find 
in it proportional parts of all numbers up to 100 ; three-place logarithms 
of numbers and the trigonometrical functions ; logarithms of numbers to 
four places; Gaussian logarithms; traverse table; correction for mid- 
latitude ; meridional parts, &c. ; as well as a useful table of constant, with 
their logarithms. Prof. Peirce mentions an interesting result of experi- 
ments conducted at the office of the American Ephemeris. The times 
occupied in doing the same piece of work by tables of 4, 5, 6, and 7 places, 
were found to be proportional to the numbers 1, 2, 3, and 4. For many 
purposes four-place tables ensure a perfectly adequate degree of accuracy. 
We are much pleased with the way in which the practical questions of size 
and form of type, arrangement of page, quality of paper, &c., have been 
attended to. The guiding lines are numerous and well-marked ; in fact, 
that fruitful source of error in computation — mistakes in following lines or 
in running down columns — seems practically eliminated. Some of the 
symbols are not altogether pleasing. The use of the symbol n for factorial 
n may appear unusual to English readers, though not unknown to continental 
mathematicians ; esc for cosec is obviously an improvement ; but why ctn 
for cot . P 
A MANUAL OF SCIENTIFIC ENQUIRY.! 
H ERE is a scientific work which has been some time in existence — seeing 
that the present is the fourth edition — which is a most valuable book, 
and which we should wish to see somewhat enlarged, and far more generally 
circulated among naval and military medical officers, and other medical men 
who are travelling abroad. It is a book which is essential to every traveller 
who wishes to profit by his trip, for we know of no other source whence he 
can obtain the amount of useful information which is contained in the pages 
of its several departments. The present edition has been brought out by 
the Rev. Robert Main, M.A., F.R.S., and in most of its departments it is as 
full as its space will admit of with facts, and with facts arranged in such 
a manner as to give the reader the best general idea possible on the subject. 
But all the chapters are not alike, some being very good and others equally 
* u Three and Four-Place Tables of Logarithmic and Trigonometric Func- 
tions.” By James Mills Peirce. Boston: Ginn Brothers, 1871. 
f “ A Manual of Scientific Enquiry, prepared for the use of Officers in 
Her Majesty’s Navy, and Travellers in general.” 4th edition. By the Rev. 
Robert Main, M.A., F.R.S. London : John Murray, 1871. 
