52 
and (4) Cyclones of the Philippines. A further classifi- 
cation, useful for some purposes, is made according to 
the rate of motion of the cyclone in its path. In con- 
nection with this part of the subject, a valuable series of 
plates gives monthly averages of pressure and tempera- 
ture, diurnal barometer curves, and a chart of cyclone 
tracks. 
The second part of the book deals with the indications 
of the approach of cyclones. While the whole section 
is of immense practical value, two chapters, on the 
photography of clouds by the photo-theodolite and 
photographic means of distinguishing true from false 
cirrus, and on Fournier’s rule and the use of Algué’s 
barocyclonometer, are of special scientific interest. The 
third section describes special characteristic cyclones, 
with a chapter on anomalies, and the fourth treats of 
winter or land storms. 
Bird Hunting on the White Nile. By H. F. Witherby. 
Pp. 117; illustrated. (London: Avowledge Office, 
1902.) 
Mr. WITHERBY may be congratulated, not only on 
having made a very successful bird-collecting trip to 
the White Nile, but also on having presented a narrative 
of his experiences to the public in an agreeable and well- 
written form. The several chapters of the book origin- 
ally appeared as articles in Avow/ledge, from which they 
have been reprinted with the addition of two appen- 
dices and various slight amendments. The illustrations 
are also somewhat more numerous. The author tells us 
that he was unfortunate enough to lose all the photo- 
graphs he took himself, owing to the intense heat and 
dryness ; but he fortunately had with him a taxidermist 
who met with better luck inthis respect, and it is to this 
gentleman that readers are indebted for the very interest- 
ing series of pictures with which the book is illustrated. 
Khartum is likely to becomea popular winter resort, and 
tourists interested in the natural history and people will 
find Mr. Witherby’s work an excellent and entertaining 
guide for the trip. 
As is indicated by the title of his volume, the author 
had for his main object the birds of the country visited, 
and of these he was successful in obtaining a large 
number of species, of which a list is given in the 
appendix. Mammals, as is so generally the case, ap- 
peared to be excessively rare, and but few specimens 
were secured; these, however, proved to be of some 
interest, as they included a bat, a mouse and a hare 
which have been described as new. Mr. Witherby inter- 
sperses his ornithological observations with accounts of 
shooting and notes on the manners and customs of the 
natives in a way calculated to attract the attention of 
readers of all classes. Unfortunately, he was unable to 
obtain any evidence on the question whether the “ croco- 
dile-bird” really enters the mouth of the unwieldy reptile 
from which it takes its name. 1, IDs 
An Introduction to Chemistry and Physics. By W. H. 
Perkin, jun., Ph.D., and Bevan Lean, D.Sc. Two 
volumes. Pp. xviii + 207 and xii+ 216. (London: 
Macmillan and Co., Ltd, 1901.) Price 2s. each. 
THE special feature of these two small volumes is the 
treatment of the subject on historical lines, which is 
certainly a scientific method; for the young mind is 
asked to travel along the same track which the growth of 
the ideas has taken. This method lends itself to a more 
literary style than that of mathematical reasoning ; and 
this, we think, is a gain, as the children in many science 
schools, where the time is chiefly taken up with science 
and mathematics, have little opportunity for such 
training. 
Broadly, the first volume deals with physics and the 
second with chemistry. The metric system is explained 
at length, but we must confess that we should have pre- 
NO. 1698, VoL. 66] 
NATURE 
[May 15, 1902 
ferred to see the gram described as a standard of mass 
and not of weight. It is certainly not true to say that a 
gram is s¢rict/y the weight of a cubic centimetre of water 
at 4° C., as the authors insist in the footnotes on pp. 18 
and 20, It would not have been necessary to call atten- 
tion to this had not great stress been laid on the fact that 
a metre is not exactly what it was originally meant 
to be. 
In the experiments an accuracy of 1 per cent. is aimed 
at, yet in fixing the boiling point graduation on a 
thermometer, p. 43, the influence of the atmospheric 
pressure is not stated. 
The present writer recently examined some 600 candi- 
dates in experimental science, and is able to trace many 
of their answers in these two books. As a rule these 
candidates seemed to follow the work well, but in some 
cases the principles of the experiments seemed beyond 
their power. Of all the quite elementary works of this 
class, perhaps these before us can be most strongly re- 
commended to the consideration of the teachers in 
primary and secondary schools. S.8: 
The Oil Chemists Handbook. By Erastus Hopkins, 
A.M., B.Sc. Pp. viiit72. (New York: John Wiley 
and Sons; London: Chapman and Hall, Ltd., 1900.) 
Price 3 dollars. 
AS stated in the introduction, the book has been written 
with the idea of supplying a want which has been felt for 
some practical working manual containing methods of 
examining oils and also data which will assist in the easy 
detection of adulteration and also give information as to 
what the adulterant is. The first chapter consists, in the 
main, of a series of tables of the general properties 
and uses of the oils and fats met with in commerce 
and of the solubility of oils, fats and waxes in various 
solvents. Following this are given the principles of the 
chief tests—the Maumené, Elaidin, Warren’s sulphur 
chloride test, &c.—and then, without an excessive amount 
of detail, the methods of analysis, in all cases references 
being given to the literature of the processes. The tables 
of chemical and physical constants which follow form an 
exceedingly useful collection, though the list might with 
advantage be a more complete one. In these tables the 
results of different observers are shown rather than mean 
figures, and the authors’ names are given. In fact, this 
quotation of sources of information forms a distinct and 
important feature of the whole book. } 
Decidedly useful is a series of five tables arranging 
oils, fats and waxes according to (a) saponification value, 
(6) iodine value, (c) Reichert Meissl value, (¢@) Hehner 
value, and (e) acetyl value. The final chapters deal with, 
fatty acids, unsaponifiable matter (such as mineral oils, 
&c.), lactones, resin and glycerol. 
Speaking generally, the book forms a valuable working 
companion for the oil chemist, without being a mere 
reference book. 
Elements of Botany. By W. J. Browne, M.A. Lond., 
M.R.I.A. Fifth edition. Pp. viiit272. (London: 
John Heywood, 1901.) Price 2s. 6d. 
WHAT is required of the elementary text-book nowadays 
is that it should furnish suitable directions and sufficient 
instruction to enable a student to collect, examine and 
work out the structure of plants for himself. The present 
work unfortunately follows the old style, being for a great 
part a mere catalogue of terms, or a series of descrip- 
tions, somewhat dry, relating to parts of the plant. In 
other respects, too, the book is quite unsuited to modern 
teaching ; the appearance of Torula early in the book, 
presenting a huge nucleus, the idea that anatomical 
sections may be cut with a knife, the enumeration of the 
twenty-four classes of the Linnzan system, all suggest 
that the book has not yet been sufficiently modernised. 
