160 
NATURE 
[Aprit 18, 1912 
a case; and later editions will benefit therefrom. 
Taking the book as it stands, it will undoubtedly 
prove of much use to men who are engaged in the 
design of steam turbines. For that reason it will 
be likely to find a large circulation, although it is 
probable that its interest will not be limited to 
engineering draughtsmen and students. 
The second volume in our list is a translation 
of a German book on “Marine Steam Turbines,” 
issued as a supplement to a treatise on “ Marine 
Engines and Boilers,” which one of the authors 
published a few years ago, and which has also 
appeared in an English translation. The author 
of this earlier work (Dr. Bauer) is the director of 
the great marine engineering works at Stettin. 
Mr. Lasche, who is joint-author with Dr. Bauer, 
is a director of the Allgemeine Electricitats Gesell- 
schaft (better known as the A.E.G.) works in 
Berlin. Both these gentlemen have had large 
experience in the design and construction of steam 
turbines of various types, and they have been | 
interested in the application of the A. E.G. turbine 
and the American Curtis turbine to the generation 
of electricity and the propulsion of ships. The 
present book, however, relates entirely to marine 
steam turbines, and the greatest prominence is 
naturally given to that class of turbine with which 
the authors have been mostly concerned. They 
very properly point out that only these two types 
of marine steam turbines and the Parsons type 
have as yet been practically tried on a large scale. 
As a matter of fact, the Parsons type has been 
used in by far the greater number of turbine- 
driven ships yet constructed. The Curtis type has 
been hitherto its only real competitor in the United 
States, and in Germany the A.E.G. type is being 
steadily developed for marine purposes. Proof of 
the relative progress of the Parsons type up to 
date is found in the circumstance that in the two 
huge Atlantic steamers now building in Germany 
for the Hamburg-American Steamship Company, 
and in all the largest and swiftest armoured 
cruisers built or building for the German fleet, 
that type is still preferred. 
The general line of treatment followed by Dr. 
Bauer and Mr. Lasche closely resembles that 
adopted by Dr. Morrow. The book is of a very 
practical character, giving methods of calcula- 
tions and examples of the application of those 
methods to the design of details of steam turbines 
of various types, the settlement of the dimensions 
of shafting and propellers, and the arrangements 
of condensing apparatus. It will have special 
interest for English readers as coming from a 
German source, and containing a considerable 
amount of information in regard to German prac- 
NO. 2216, VOL. 89] 
tice. In size, the book is only about half as 
large as that noticed above. It is exceedingly 
well produced, and very tersely expressed, the 
authors stating their own conclusions on many 
points where differences of opinion prevail, with- 
out entering into elaborate arguments in support 
of those opinions. No objection need ‘be taken to 
this method of treatment; in fact, it has distinct 
advantages for the men who are expected to be 
the principal users of the volume; but it is neces- 
sary to note that in many points, especially in 
those where comparisons are made between 
British and German or American types of turbines, 
the opinions expressed by the writers are not 
shared by no less competent authorities. In some 
cases the endeavour to compress statements within 
narrow limits has been accompanied by what, no 
doubt, is an unintentional omission of important 
facts. These, however, may be regarded as minor 
blemishes on what is, on the whole, a good per- 
formance; and there can be no doubt that such a 
book will naturally find a place on the shelves of 
all who are interested in the design of steam 
turbines, representing as it does the experience of 
two leading German engineers. 
The third book in our list is a slender volume 
of less than sixty pages, in which the Rede Lecture 
for 1911 by Sir Charles Parsons is reproduced. 
The authorities of Cambridge were fortunate 
enough to secure, on this occasion, a lecturer who 
is one of the most distinguished living graduates 
of the University, and to find him ready to 
describe the principal features of his own great 
invention, as well as those of competing types of 
steam turbines. 
This little book contains a wealth of illustra- 
tions, an epitome of the history of the progress of 
steam turbines, and a summary of the matured 
opinions of the man who knows most about that 
class of prime movers. Sir Charles Parsons has 
set down in modest and simple fashion his main 
conclusions on a subject of which he is the acknow- 
ledged master. The utterance is itself but a brief 
summary of facts and opinions; consequently, it 
is impossible even to mention its main points in 
this review. All who are interested in the subject 
should read the book itself, and its low price ought 
to ensure for it a large circulation 
One characteristic feature of the book, however, 
deserves mention. Throughout his references to 
types of turbines which have been originated by 
other inventors, the author displays great fairness 
of judgment and a generous appreciation of merits 
possessed by machines which are in competition 
with turbines designed by himself. Sir Charles 
Parsons has thus taken a course differing from 
