486 
at presenting to senior students and investigators 
the results of recent work in a few of those 
branches which are at present attracting attention. 
It is supplementary to the text-books, and should 
prove of great value to those whom the subject 
more nearly concerns. The value of the work is 
enhanced by the author’s. choice of material, since 
he has selected those subjects with which he was 
specially familiar and on which he was able to 
write with a first-hand knowledge. Starting with 
the classic researches of Brown and Morris, the 
author deals in the first two chapters with the 
carbohydrates of the leaf in relation to photo- 
synthesis and with the methods of estimating 
carbohydrates in plant extracts. This is followed 
by short chapters on the carbohydrates of the 
cellular cryptogams. Other chapters deal with 
osmotic pressure and its relation to plant distribu- 
tion, and to morphological variations; the per- 
meability of protoplasm and of other organic 
membranes; and the magnitudes of osmotic pres- 
sures and electrical conductivities in plants. A 
chapter on the functions of the wood jis followed 
by an account of the plant oxydases and their 
relation to pigmentation, and the final chapter is on 
the oxydases in relation to plant pathology and to 
technology. At the end of the volume there is a 
bibliography classified under the headings of the 
subject-matter adopted in the text. 
WORKS ON CIVIL ENGINEERING. 
(1) American _ Civil Engineers’ Pocket-Book. 
Editor-in-chief, M. Merriman. Third edition, 
enlarged. Pp. ix+1571. (New York: John 
Wiley and Sons, Inc.; London: Chapman and 
Hall, Ltd., 1916.) Price 21s. net. 
(2) Parks and Park Engineering. By Prof. W. T. 
Lyle. Pp. viii+ 130. (New York: John Wiley 
and Sons, Inc.; London: Chapman and Hall, 
Ltd., 1916.) Price 5s. 6d. net. 
(3) Masonry Dam Design, including High Masonry 
Dams. By Dr. C. E. Morrison and Orrin L. 
Brodie. Second edition, revised and enlarged. 
Pp. ix+276. (New York: John Wiley and 
Sons, Inc.; London: Chapman and Hall, Ltd., 
1916.) Price ros. 6d. net. 
(4) Earth Pressure, Retaining Walls, and Bins. 
By Prof. William Cain. Pp. x+287. (New 
York: John Wiley and Sons, Inc.; London: 
Chapman and Hall, Ltd., 1916.) Price ros. 6d. 
net. 
(1) HE “American Civil Engineers’ Pocket- 
Book” has already established an envi- 
able reputation for trustworthiness and complete- 
ness, which is well maintained in the third edition. 
A new section of ninety-six pages on river and 
harbour works has been added, whilst important 
additions have been made in the other sections. 
The scope of the book is wide, each subject being 
written by a specialist in the particular branch 
dealt with, although the treatment is simple and 
requires a minimum of previous knowledge. 
Valuable features of the book are the numerous 
NO: 2469, VOL. 98] 
NATURE 
[FEBRUARY 22, 1917 
examples worked out where concise and accurate 
description would otherwise be difficult. Although 
the question of cost varies*enormously with time 
and locality, the tables of prices of works executed _ 
will add greatly to the use of the volume. 
In view of the importance of the subject to — 
makers and users of machinery, it is somewhat. 
disappointing to find only one short paragraph 
devoted to hardness: tests of metals. We also 
think that it is time some of the work which has 
been carried out lately upon struts and columns 
should be incorporated. ; 
This pocket-book is one which is probabl 
destined to form a standard reference-book for, 
every civil engineer. i ok i 
(2) It is now generally recognised that amongst 
the best investments for an urban community is 
the provision of parks and recreation-grounds, 
Indeed, in several recent cases the actual apprecia- 
tion in value of surrounding property following” 
upon the transformation of waste land to this 
purpose has been greater than the outlay. A. 
very readable book upon the subject of parks and — 
park engineering has been written by Prof. W. T. 
Lyle, of Lafayette College, which, although deal-. 
ing with the American aspect of the case, will be, 
found useful by members of public bodies respon— 
sible for the, planning of our cities and towns. 
The first chapter of the book deals with the 
acquisition of parks and their lay-out. Other 
chapters are concerned with the survey and design, — 
while interesting and instructive articles on labour 
and contracts and construction should prove of 
great assistance to the non-professional man, and 
also to young and inexperienced engineers of con- — 
struction. In his preface the author points out 
that “the art of the park engineer, though a 
specialty, is, however, not a narrow specialty. 
He must be proficient in matters pertaining to the 
acquisition of lands, and be well versed in a great 
variety of engineering operations, such as earth 
excavation, masonry, waterworks and sewerage 
construction, road building and lighting, and 
occasionally the construction of steel and re- 
inforced-concrete bridges. He must also be a 
good expert witness.”” The scope is very wide, 
and can only be superficially treated in one 
volume. The book will undoubtedly fill a useful 
place and serve as an introduction to more 
specialised works on construction. ; 
(3) During the last few years there has been 
considerable discussion amongst engineers as to 
what methods should be adopted and what 
assumptions made in the design of high masonry 
dams. The subject is of extreme importance, 
since we have, on one hand, large expenditure 
of money in providing margins of safety above 
those really necessary, and, on the other, the 
fact that failure must be rendered impossible. 
The most recent methods of calculation and 
design are very ably treated in Morrison and 
Brodie’s “Masonry Dam Design,” the second 
edition of which has just been published. In the 
revision the authors have amplified a number of 
points which were treated very shortly in the 
