Marcu 21, 1907] 
NATURE 
485 
the case of a crane hook is deduced, and the method 
of Résal is explained by which the application of the 
formula is much simplified. The last two chapters 
of this section are devoted to arches and arched ribs, 
and to foundation and retaining walls; this is a part 
of the subject of the strength of materials which 
generally proves a great stumbling-block to the 
engineering student, and the authors are to be con- 
gratulated on the lucid and thorough fashion in 
which they have set forth the various solutions which 
have been found most satisfactory for problems which 
have been well-known subjects of controversy among 
engineers and mathematicians for a century or 
more. : 
The six chapters of part ii. are devoted to the 
physical properties of materials and the most modern 
methods of determining accurately the various 
physical constants required in the formule of part i. 
Typical testing machines are illustrated and ex- 
plained, and the various types of apparatus in general 
use for measuring the stresses in the material under- 
going test are described. The materials dealt with 
include iron and steel, reinforced concrete, and the 
other building materials employed by engineers and 
architects; a number of useful tables are given, and 
also the standard specifications proposed by the 
American Society for Testing Materials. 
The authors have succeeded in producing a new 
English text-book in which the important subject of 
the strength of materials, the foundation upon which 
the whole structure of engineering science is based, 
is treated in a far more complete and thorough 
fashion than has been the case in the majority of 
the text-books hitherto available to the engineering 
student, and certain sections of it should prove of 
great service to those who are actively engaged in 
engineering design. 
SCIENCE IN POETRRY. 
Nature Knowledge in Modern Poetry. By Alexander 
Mackie. Pp. vii+132. (London: Longmans, 
Green and Co., 1906.) Price 2s. 6d. net. 
N this book the author deals in a very interesting 
manner with the many references to the aspects 
of nature in the poetical works of Tennyson, Words- 
worth, Matthew Arnold, and Lowell. 
We find these poets taking delight in alluding to 
animated nature in many different ways. Not only 
do flowers, trees, and foliage of all kinds occupy a 
prominent place in their poems, but animal life 
figures almost as importantly, birds more especially. 
Tennyson’s references to horses and dogs show an 
intimate knowledge of these animals, though they do 
not convey the spirit of one in the habit of taking 
part in sport; and the author points out that Tenny- 
son was not a sportsman. Matthew Arnold’s love 
of dogs is also very obvious, and his poems show how 
much sympathy he had with them, and what a close 
observer he was of their ways and habits. This 
comes Out more especially in the poems dedicated to 
his household pets. 
Interest in the insect world is shown to a greater 
extent by Tennyson, for he alludes to it frequently, 
NO. 1951, VOL. 75] 
and always with the accuracy which reveals great 
knowledge. Lowell refers more especially to the bee. 
Love of bird life is common to all these poets, but 
it is worthy of note, and also pointed out by the 
author, that the great characteristic of Tennyson’s 
work is that he describes the bird’s notes to a great 
extent, and has the happy knack of so doing that 
the bird he is referring to is unmistakable. 
We gather in many ways that Tennyson was the 
more truly scientific man of the poets referred to. 
The character of his allusions and the accurate detail 
into which he goes are, moreover, beyond the 
knowledge of the casual observer. Wordsworth was 
more an esctatic admirer; as the author tells us, ‘‘ his 
outlook was broader, and in one sense less intimate ”” 
than Tennyson’s. He was accurate in his descrip- 
tions, but seemed almost fearful lest an intimate 
knowledge should do away with the beauty and poetry 
of nature. He says, 
“ Sweet is the lore which Nature brings; 
Our meddling intellect 
Misshapes the beauteous forms of things ; 
We murder to dissect.” 
And again, 
‘“ Enough of Science and of Art; 
Close up those barren leaves ; 
Come forth and bring with you a heart 
That watches and receives.” 
In the preface to ‘‘ This lawn a carpet all alive,” 
Wordsworth appears a little more in sympathy with 
science, but in spite of this he still conveys the feel- 
ing that he is of opinion that nature will reveal her 
mysteries unsought. 
Tennyson’s love of geology is 
‘frequent references to it and the 
which clearly show he must have read a good deal 
on this as indeed on many other less popular sub- 
jects; for instance, he does not shun allusions to the 
nebular hypothesis, spectrum analysis, and astro- 
It seems evident that he accepted the theory 
apparent in the 
similes he gives, 
nomy. 
of evolution, for many quotations might be made to 
show it; but the author contents himself with 
the following, from ‘‘ Locksley Hall Sixty Years 
After ’? :— 
“ Eyolution ever climbing after some ideal good, 
And Reversicn ever dragging Evolution in the mud. 
+ % * * * ¥ 
Many an aeon moulded earth before her highest, man, 
was born, 
Many an aeon too may pass when earth is manless and 
forlorn.” . 
We see, therefore, that these poets deal largely 
with things of scientific interest, and all lovers of 
nature will find the book of great and permanent 
value. 
OUR BOOK SHELF. 
Geometrische Kristallographie. By Ernst Sommer- 
feldt. Pp. x+139; illustrated. (Leipzig: W- 
Engelmann, 1906.) Price 7s. net. 
Tue closing decade of the last century witnessed 
much progress made in the development of the 
geometrical theory of erystal structure, and we may 
now have confidence in the certainty of our know- 
ledge regarding the possible types of crystalline 
