412 
NATURE 
[Marcu 4, 1897 
different factors at work in the causation of compressed 
air illness. He inclines to the view that too much im- 
portance has hitherto been attached to the length of 
the “locking-out” process. Other observers have laid 
great stress upon the necessity of the workers passing 
gradually from the compressed to the ordinary atmo- 
sphere, and have always advised employers to make 
arrangements accordingly. A factor of great importance, 
according to the author, is the ventilation of the com- 
pressed air space in which the men work. Tables are 
given, from which it appears that an increase from 4000 
to 12,000 cubic feet in the supply of fresh air per man 
per hour was followed by a reduction, in the cases of 
illness per 100 days, of from 28 to wz. The length of 
-stay in the compressed air, and the height of the pres- 
sure, especially the former, are factors the importance 
of which is confirmed by the author. At the conclusion 
-of a criticism of the theories hitherto advanced to ex- 
plain the symptoms occurring in compressed air illness, 
Dr. Snell, relying chiefly upon the experimental results 
of Bert, suggests that the symptoms are due to an escape 
from the blood, under ordinary atmospheric pressure, 0 
the excess of gases which were dissolved in it, wzé the 
pulmonary capillaries, during the stay in the compressed 
air. The different constituents of the compressed air 
atmosphere have different coefficients of absorption, 
carbon dioxide, for instance, being eighty-eight times as 
soluble as nitrogen, and forty-five times as soluble as 
oxygen. The value of ventilation—z.e. frequent removal 
of carbon dioxide—as a preventive of compressed air ill- 
ness is, according to Dr. Snell, due to its great solubility, 
a relatively large quantity of this gas entering into 
solution in the blood, in a given time, as compared 
with oxygen and nitrogen ; hence a larger escape of gas 
takes place, upon reaching the normal atmosphere, when 
the atmosphere of the compressed air space has been 
rich in carbon dioxide. Thus it is owing not to its 
chemical, but to its physical properties, that carbon 
dioxide acts injuriously in this instance. Under the 
head of treatment the author discusses prevention and 
cure, the most important remedial agent being re- 
compression. The medical air lock, used atthe Blackwall 
Tunnel, is described. A comprehensive bibliography 
and an accurate index conclude the work. FF. W. T. 
THE ZOOLOGICAL RECORD. 
The Zoological Record. Vol. xxxii. Being records of 
zoological literature relating chiefly to the year 1895. 
By many authors. Edited (for the Zoological Society 
of London) by D. Sharp, M.A., F.R.S., F.Z.S., &c. 
8vo. Pp. 1180. (London: Gurney and Jackson, 1896.) 
HE tthirty-second volume of the Zoological Record, 
containing an account of the oological literature 
of 1895, was issued shortly before the close of last year, 
with its customary and most praiseworthy regularity. It 
is edited for the Zoological Society of London, whose 
property the Record is, and at whose expense it is carried 
on, by Dr. David Sharp, F.R.S., the Curator in Zoology | 
| number of new generic terms would stand 1639 for 1894, 
of the Cambridge University Museum, with the assistance 
of fourteen other naturalists in different departments of 
the subject. The volume is rather thicker than those 
NO. 1427, VOL. 55] 
which have preceded it. In the first place, as the editor 
apologetically explains, this is in consequence of the 
literature of two years, in the case of four out of the 
eighteen departments left in arrear last year, being 
included in the present volume. But the amount of 
zoological work performed every year also increases as 
science progresses. More volumes and more papers are 
published, and new scientific periodicals are continually 
being started. All these contribute to the annual increase 
in size of the Zoological Record. To form an idea of the 
number of periodicals which the much harassed recorder 
has now to consult, it is only necessary to cast one’s eye 
over the alphabetical list of the abbreviations of their titles, 
which the general editor has prepared and printed in the 
present volume. Each of these abbreviations is accom- 
panied by the full title of the periodical, the place of its 
publication, and the most accessible libraries in London 
and Cambridge in which a copy of it is to be found. 
This list occupies fifty-four closely printed pages in the 
present volume, and numerous additions are made to it 
every year. 
As regards the eighteen different reports referring to 
the various departments of the animal kingdom, which 
are included in the present Record, it is difficult to com- 
pare one with another—at any rate, for one who does not 
profess to be intimately acquainted with all the eighteen 
subjects. There can be no doubt that Record xiii. on the 
Insecta, which is undertaken by Dr. Sharp himself, is 
the bulkiest. It contains no less than 387 closely-printed 
pages, and the task of preparing it must have involved 
much time and very serious labour. But if we had to 
give a prize for the best of the eighteen records (putting 
Insecta on one side), we should rather be inclined to 
bestow sucha reward on Mr. Lydekker, because we think 
his introduction is the best. Mr. Lydekker’s introduction 
gives a short summary of the principal events in the 
history of mammals during the year 1895. Other 
recorders also give introductions, but not, we think, in 
so complete a form. Dr. Sharp gives us no introduction 
to “ Aves,’ and Mr. Boulenger omits this very essential 
feature in his two records. Other authors give a few 
lines only, which are hardly sufficient, but many of them, 
we regret to see, omit it altogether. We are strongly of 
opinion that a summary account of the most remarkable 
zoological publications and discoveries of the year should 
be prefaced to the list of publications in every subject 
and recommend the general editor to insist on this being 
done in the future. Many naturalists are sufficiently 
interested in a particular subject to read such a summary, 
but do not care to go into the mass of details. Dr. 
Sharp himself sets his recorders a good example in 
this respect. 
At the close of the volume will be found a most useful 
alphabetical list of the names of new genera and sub- 
genera in zoology established in 1895, and mentioned in 
the present volume. The total number of such names in 
this volume is 1906. Last year the total number was 
1438 ; but, allowing for the four records omitted in the 
last volume, and duplicated on the present occasion, the 
and 1707 for 1895, showing, as is usual, a gradual but 
steady increase. 
