628 
NATURE 
(5) Mr. Gladstone has produced one of the best 
local faunas that we have seen, although it seems 
almost a pity that, in order to save space, the 
Latin technical names are omitted from the index, 
as are, for the same reason, almost all references 
to authorities. Another peculiarity of the index 
is that it includes local and Gaelic names which 
are not given in the body of the work. Thus the 
entry, ‘‘Briskie (Chaffinch), 20,” represents the 
only appearance of the former word. It ais 
interesting to find that, contrary to the predictions 
of objectors, writers of local faunas have not been 
slow to adopt the most recent advances in nomen- 
clature. Thus Mr. Gladstone’s list of Dumfries- 
shire birds includes several sub-species, whilst 
amongst his mammals are found many of the most 
newly unearthed genera (such as Nyctalus for the 
Noctule), for which we are indebted to the laws 
of priority. He has not, however, ventured into 
sub-species of mammals, and, indeed, it is difficult 
to see how a local writer can do so until an 
authoritative text-book has been issued. It is 
most useful to find the mammals extinct within 
prehistoric or historic times included, such as the 
urus, elk, reindeer, wolf, and brown bear; but 
by a curious mistake the wild boar is sandwiched 
between the mountain hare and rabbit. Space 
does not permit allusions to the amphibia, fishes, 
and reptiles. 
(6) Mr. Claude Morley’s small volume on two 
tribes of Ichneumonide is the first of a series, for 
which, as we are informed by Dr. Harmer, we 
are indebted to Mr. Morley’s having undertaken 
to bring a very large accumulation of unsorted 
specimens at the British Museum into order, these, 
as it appears, not having been arranged since 
Frederick Smith left them in 1860. The two tribes 
included in the “Revision” have been selected 
on account of considerations of an entirely practical 
nature, and not because their close association 
is indicated by a study of their respective sys- 
tematic positions. It is not surprising to find 
that the author brings forward a somewhat large 
proportion of apparently new species, with a few 
additional genera, on the possession of all the 
types of which the national collections may be 
congratulated. Many of these have long been 
awaiting description, Mr. H. W. Bate’s rich 
South American collection made during 1848-1859 
affording a particular instance. The book includes 
one coloured plate by Mr. Rupert Stanton of a 
British example of the widespread Ophion luteus. 
The descriptions and notes on geographical dis- 
tribution appear to have been very carefully drawn 
up, and the author states that he has been able 
to consult practically all the literature. The 
volume will be most valuable to students. 
NO. 2234, VOL. 89] 
[AuGuUST 22, 1912 
CONCERNING HEAT. 
(1) Heat Engines. By H. A. Garratt. Pp. xii+ 
332. (London: Edward Arnold, n.d.) Price 
6s 
(2) Modern Destructor Practice. By W. F. Good- 
rich. Pp. xvi+278. (London: C. Griffin and 
Comelid’, 1912.) Manicesns seamen, 
(3) Barker on Heating: the Theory and Practice 
of Heating and Ventilation. By A. H. Barker. 
Pp. xvi+64o+Ixxvi. (London: J. F. Phillips 
and Son, Ltd., 1912.) Price 25s. net. 
(1) N this volume Mr. Garratt follows along 
the paths trodden by most writers of 
elementary text-books on heat engines, but with 
considerable discrimination and judgment, which 
has resulted in a very concise and readable work 
for the technical student. The difficulties of pre- 
senting even elementary thermodynamics to 
students imperfectly equipped with mathematics 
are well known to every teacher, and various 
expedients have to be devised to bridge the gaps 
left by mathematical shortcomings. The author 
skips from one equation to another when the con- 
necting link involves a knowledge of the calculus, 
as, for instance, when deriving the work done by 
a gas expanding adiabatically. Such omissions 
are quite justifiable, for the earnest student can 
make good the hiatus either concurrently or after- 
wards. : 
With some exceptions of this kind, the thermo- 
dynamic part of the book is very straightforward, 
and especially the method of dealing with that 
fugitive quantity “entropy,” in which the author 
steers clear of the hopeless redundancy and mys- 
ticism which various writers bring to bear with 
the worthy object of making things clear. 
Probably there is no part of the subject of thermo- 
dynamics which is at the same time the object 
of so much pedagogic endeavour and resists the 
attacks so well. We are glad to find a well- 
written chapter on the mechanism of reciprocating 
engines, for a thorough understanding of the 
fundamental principles-of slide valves and motions 
is the best equipment for the mechanical engineer. 
The steam turbine is given a chapter to itself, in 
which the various forms of turbine combining 
different degrees of the “reaction ” and “impulse ” 
types are described with their mechanical details. 
The introduction to the theory of the steam 
turbine through that of the water turbine is not 
happy, and the student of steam turbines will find 
“cc 
| it convenient to forget Bernouilli’s equation when 
dealing with an expanding gas. Though the 
author alludes to the difference, the analogy is so 
far from complete that it would be better to treat 
the steam turbine as arising directly from the flow 
of an expanding gas. The author is well up to 
