NOVEMBER 8, 1906 | 
INSANE GO SID. 29 
they may be 
said, as books 
rapidly to ex- 
Taking these two works together, 
recommended to the expert botanist, as 
of reference in cases where he wishes 
tend his definition of special terms. 
OUR BOOK 
First Steps in the Calculus. 
Heyden. Pp. vi+216. (London : 
1906.) Price 3s. 
SHELF. 
By A. F. van der 
Edward Arnold, 
Tne modest claim expressed by the author in his 
preface, in the hope “that a step in the right direc- 
tion has been taken towards producing a text-book 
suitable for an ordinary class in a Secondary Day 
School,”’ is a claim which it would be impossible to 
deny. Experience has shown that geometrical illus- 
trations, such as those on pp. 32-34, 45, and 96, are 
actually of great help to beginners, and we quite 
agree with the author that complicated theorems, such 
as Taylor’s expansion (when applied to any but 
rational integral functions), should not be taken too 
early. The introduction (p. 93) of Lodge’s treatment 
of the connection between integration and summation 
would be good if the step where the assumption is 
made were clearly pointed out. But there are many 
points which the author might have considered more 
fully before issuing the book. While the sine and 
cosine are properly differentiated, it is surprising to 
find such a clumsy method employed for the tangent. 
In order to differentiate a power the beginner is re- 
quired to swallow the usual series of terms which 
vanish in the limit, instead of treating the power as 
‘a product. 
In one or two places, in putting the chord of a 
curve equal to the corresponding arc, a line of ex- 
planation, or even a reference number, would have 
made things much clearer. , The introduction of e as 
early as chapter vi. is no doubt in accordance with 
traditions, but it is a pity to defer the study of the 
calculus until the text-books in algebra referred to 
for a discussion of exponential series have been read. 
Rational integral functions, with applications to 
geometry and physics, afford plenty of material for 
the beginner. Lastly, the questions in examples ix. 
are very important indeed, but they give difficulty to 
many students who can hardly be described as 
beginners. The general conclusion is that the book 
would be more correctly described by a title which 
did not suggest something so very elementary. It is 
well suited for the class-room. 
A Manual of Hydraulics. By R. Busquet. Trans- 
lated by A. H. Peake. Pp. viii+312. (London: 
Edward Arnold, 1906.) Price 7s. 6d. net. 
Tuts book is a translation of a French treatise on 
hydraulics by Prof. Busquet, of the Ecole indus- 
trielle de Lyon. It claims to be a text-book of applied 
hydraulics in which complete technical theories, and 
_all useful calculations for the erection of hydraulic 
plant are presented. The translator appears to have 
done his work well, and to have given the meaning of 
the author in English terms and phrases. While the 
same arithmetical methods used in the original have 
been adhered to, the dimensions have been changed 
into ordinary British units, and the constants given 
in the formule have been modified to suit the change. 
The first three chapters deal with the elementary prin- 
ciples of the flow of water in open channels and 
pipes, and the last chapter with the flow over weirs. 
These subjects are dealt with in'a simple and prac- | 
tical way. They do not, however, contain any inform- 
NO. 1932, VOL. 75| 
ation that is not to be found in English text-books on 
the same subject. 
The fourth chapter, which occupies about half the 
book, is devoted to the theory and description of 
hydraulic motors and engines used to transform the 
energy contained in a head of water into mechanical 
work. The use of waterfalls hitherto has been 
limited, because the application of the energy could 
only be used locally, but since electricity has come 
into use for the transmission of power to great dis- 
tances, water has assumed a new and increased value 
as an economical source for the production of power, 
and the construction of hydraulic installations is in- 
creasing at a rapid rate. The use of water-power 
and the machinery required to adapt it to commercial 
use have received very little attention from the 
authors of modern English and American treatises on 
hydraulics. 
The writer does not know of any book that deals 
with this subject in so practical a way as the one 
under notice. The several kinds of water-wheels in 
use are described and illustrated, and their theoretical 
and useful value demonstrated. Turbines, which are 
now being largely used for the distribution of water- 
power, are freely dealt with, and the merits of the 
different forms of this machine discussed. The book 
is calculated to be of service both to students of prac- 
tical hydraulics and to those engaged in designing 
and carrying out works for the utilisation of water- 
power. 
Guide to the Principal Families of Flowering Plants. 
(After Engler’s System.) By J. Adams. Pp. 
iv+46. (Dublin: Sealy, Bryers and Walker, 1906.) 
Priceyrs. net: 
A CONVENIENT summary for determining the orders of 
flowering plants is a much required desideratum. 
The difficulties in compiling such a summary are very 
great, not the least being due to the impossibility of 
defining the limits in certain cases between allied 
orders. Mr. Adams has not attempted such details, 
preferring to leave out a large number of orders and 
to sacrifice difficult distinctions to brevity and general 
utility. With regard to the statement that the book 
is after Engler’s system, this applies only to the 
names of the orders; the method of separation is 
purely artificial. Thus, in the Archichlamydez, para- 
sites and insectivorous plants are first eliminated, then 
consideration of the vegetative organs provides the 
next stages in differentiation. So far as practical 
tests have been applied with a few orders, the tables 
have given quite satisfactory results. 
The Extra Pharmacopoeia of Martindale and West- 
cott. Revised by Dr. W. Harrison Martindale and 
W. Wynn Westcott. Twelfth edition. Bp 
xxx+1045. (London: H. K. Lewis, 1906.) Price 
Ios, net. 
Tus most useful volume has now reached its twelfth 
edition, and extends to more than a thousand pages. 
The pages are small ones, but packed with inform- 
ation, and the paper is thin, so the volume still re- 
mains one of handy size. The book is more than 
its name indicates; it not only includes remedial 
agents which have been introduced up till now into 
medical practice, but contains a great deal of inform- 
ation regarding recent research in disease. For 
instance, we find an excellent summary of the present 
state of the cancer question, the newest methods of 
bacteriological investigation, and a concise statement 
of modern views on toxins and antitoxins, serum 
therapy, opsonins, and the like. No busy practitioner 
can afford to do without such a convenient and trust- 
worthy vade mecum, 
