264 
NATURE 
[ Fed. 2, 1871 


OUR BOOK SHELF 
A Ride through the disturbed Districts of New Zealand, 
together with some Account of the South Sea Islands. 
Being Selections from the Journals and Letters of Lieut. 
the Hon Herbert Meade, R.'N., edited by his Brother. 
With Maps and Jllustrations from the 
Sketches. (Murray, 1870.) 
THE title-page sufficiently describes this book, which is 
illustrated by some nice woodcuts, and several coloured 
lithographs of less merit. There is a good description of the 
Geysers of New Zealand, and of the state of the native in- 
surrection in 1865 ; with some exciting narratives of attacks 
on Papuan cannibals in the New Hebrides. A good- 
sized house, built in a lofty tree and used as a fort, was 
seen in one of the Solomon Islands. One cannot but 
regret that the opportunities possessed by our officers 
on the Pacific Station for inves‘igating the little-known 
natural history of the islands, are so seldom utilised. The | 
author of this book often shoots, but hardly seems aware 
that his game could be of any other use than for food. 
The only natural history passage in the book is the 
following, dated Upolu, Samoan Islands :—‘‘ Saw a very 
rare bird, the Dodunculus, native name, which is peculiar | 
to this island. It has the feet of a pigeon, beak of a hawk,” 
Author’s | 

&c., &c. Dodunculus! nativename! ! A. R. W. 
Metals, their Properties and Treatment By C. L. 
Bloxam, Professor of Chemistry in King’s College, 
London ; Professor of Chemistry in the Royal Military | 
Academy, and in the Department of Artillery Studies, 
Woolwich. Pp. 296. (London : Longmans, Green and | 
Co., 1870.) 
THis is one of the text-books of science which are being | 
edited by Mr. T. M. Goodeve and published by Messrs. | 
Longmans. The series is intended to supply a want that 
has long been felt of exact and complete works on | 
mechanical and physical science for the use of schools, and | 
for the self-instruction of working men. A difficulty must | 
have been experienced by many who are engaged in teach- | 
ing science, when asked to recommend a small and in- 
expensive text-book, which may at the same time be so 
simply and clearly written as to be useful to those who 
have not had a scientific education, and who have not the 
advantage of being able to attend long courses of lectures. 
Many popular books on scientific subjects have been 
written, but they are not unfrequently somewhat inaccu- | 
rate; difficult questions being often omitted, or, what 
is worse, treated in a superficial manner which is likely to 
mislead the student, inducing him to believe that these 
questions are very simple, and deluding him with the 
notion that he knows all about them. He is thus frequently | 
disappointed at a subsequent period by finding that on 
studying the subject more minutely, it is much more 
complex than he at first imagined, and that many of the 
simple ideas which he had carefully fixed in his mind | 
have to be discarded, and new ones acquired. 
The book opens with an introductory section on the 
properties and treatment of metals, containing many | 
use ul tables, such as specific gravities, fusing points, 
conductivity, &c. The more common metals used in the 
arts are alone discussed,so as not to introduce unnecessary 
complication. The remaining sections of the book treat 
of iron and steel, copper, tin, zinc, lead, silver, gold, mer- 
cury, platinum, palladium, antimony, bismuth, aluminium, 
magnesium, and cadmium, The last six being far less 
important than the others, are very shorily described, and 
only occupy twelve pages. 
Each section commences with a description of the ores 
of the metal under consideration, their composition 
being given, and also the per-centage of metal present. 
This is followed by the methods of treating the ores in 
order to extract the metal, chemical reactions being written 
in words without formule, so hat no preliminary know- 

| whom the wish was father to the thought. 
ledge is necessary. The mechanical treatment of the re- 
duced metal is then detailed, and its useful applications 
in the pure condition or in the form of alloys. The book 
is profusely illustrated with good woodcuts, and is written 
in an extremely interesting manner which cannot fail to 
attract the attention of the student. This, together with 
the trustworthiness of its contents and its low price, will 
render the treatise extremely useful for scientific in- 
struction. If the remaining text-books of the series pos- 
sess all the advantages which are presented by this one, 
the thanks of teachers and students of science will be due 
to the editor and publishers for their undertaking. 
| Odd Showers: or, Explanations of the Rain of Insects, 
Fishes, and Lizards; Swot, Sand, and Ashes; Red 
Rain and Snow ; Meteoric Stones; and other Bodies. 
By Carribber. (London: Kerby and Son, 1870.) 
| Tuts little book is stated on the title-page to be “ intended 
chiefly for young persons;” but others will, doubtless, gain 
information from it, as to the causes of the sudden appear- 
ance of swarms of insects and other animals, and showers 
of rain tinged with various colours,with respect to which so 
many popular errors are afloat. The writer derives his 
experience from a long residence in Canada, and one ex- 
planation of so-called ‘‘showers of blood” is new to us, 
that it is caused by the exudation of a crimson fluid by 
various chrysalides when passing into the imago state, 
The writer states that, on one’occasion, twenty-eight chry- 
salides of Vanessa antiopa, the Camberwell Beauty, which 
he had preserved in a small room, underwent transforma- 
tion in a single day in July , when the walls and floor 
were bespattered with a bright crimson-coloured substance 
resemLling blood, as to give the appearance of a regular 
shower of the fluid. 

LETTERS TO THE EDITOR 
[The Editor does not hold himself responsible for opinions expressed 
by his Correspondents. No notice is taken of anonymous 
communications. ] 
Natural Science at Cambridge 
In Nature for January 12, 1871 (p. 209), there appeared an 
article Headed ‘‘ Natural Science at Cambridge,” which has the 
air of having been promulgated fermissu (if not auctoritate) 
suferiorum. It is extremely gratifying to read the list of exhi- 
bitions and scholarships founded or proposed to be founded in ~ 
certain Colleges in this University, but the concluding sentence of 
the article has struck me as having been penned Ly one with 
It is said that 
‘“most of the Colleges are understood to be willing to award 
Fellowships for merit in Natural Science equivalent to that for 
which they are in the habit of givingthem for Classics and Mathe- 
matics.” Now this is entirely at variance with my own opinion 
on the subject, formed on a somewhat wide acquaintance with 
members of various colleges ; and I would beg of the writer to 
be good enough to inform the public through your columns, first, 
how many Fellowships have solely and actually been awarded for 
merit in Natural Science, and, secondly, which of the sixteen 
colleges, besides Trinity, have absolutely declared that a Fellow- 
ship shall be the reward of great proficiency in Natural Science, 
I need not say how glad I shall be to find that my opinion is 
erroneous. M. A. 
Cambridge, Jan. 28 

Yellow 
Ir was not from any experiments of my own, but on the 
authority of Helmholtz, that | asserted the identity of brown with 
a dark yellow or orange. He found that the pure red and yellow 
of the spectrum gave the various shades of brown when seen by 
the side of more brilliantly lighted white surfaces. (Physiolo- 
gische Optik, p. 281.) ‘There is therefore nothing in the nature of 
the colour to exclude complete saturation, although it may well 
happen that most of the browns we ordinarily see fall somewhat 
short of it. 
