1875.] Notices of Books. 257 
Elements of Magnetism and Electricity. By JoHN ANGELL, 
Senior Science Master, Manchester Grammar School, with 
120 illustrations. London and Glasgow: William Collins, 
Sons, and Co. 1875. 
Tuis very cheap and comprehensive little manual belongs to the 
capital series of elementary works on science which Messrs. 
Collins are now issuing. It is almost entirely devoted to 
Magnetism and Frictional Electricity, one chapter only at the end 
of the book being devoted to Voltaic Electricity. The figures are 
plain, but quite sufficient for their purpose ; we may particularly 
call attention to the representations of magnetic curves (Figs. 
I9—23), and to the figures showing electrical distribution on 
various surfaces (Fig. 89). Hints are frequently given for the 
construction of cheap apparatus, but these cannot always be 
relied upon; for example, we are told how “an efficient electrical 
machine,” capable of performing all the ordinary experiments, 
may be constructed out of a common black wine-bottle for a ‘‘ few 
pence ;” but all who have tried to make an electrical machine 
know how very difficult it is to get anything like an efficient 
machine at a cost of much time and many shillings. There are 
a thousand difficulties in the way: to mount the cylinder— 
to make it rotate in a horizontal plane—to manipulate the 
even pressure of the rubber—are among them. Again, some of 
the explanations are insufficient; for example, in describing 
the electrical whirl, the author says:—‘‘On working the machine, 
a powerful wind, the electrical aura, will be produced, which, 
reacting against the points, will drive the wheel round with great 
velocity.” But he does not explain why the wind is produced. It 
is a general fault in elementary works, in which as much matter 
as possible is introduced at the expense of clearness, to describe 
experiments without fully explaining them. But the book is 
distinétly good, and a marvel of cheapness, and will be found 
most useful as a commencing text-book. 
Elements of Animal Physiology, chiefly Human, with Hints on 
Practical Work, Dissection, &c. By JoHN ANGELL, Senior 
Science Master, Manchester Grammar School. London 
and Glasgow: William Collins and Sons. 1875. 
Tus is a shilling book containing 92 capital figures, and more 
than 500 separate paragraphs of text. It is a marvel of cheap- 
ness, and although we must of course regard it as, to a great 
extent, a compilation, it contains‘ a great amount of sound 
information and useful knowledge. It is divided into twenty 
chapters: the first two treat of the general structure and 
functions of the human body; here we notice a complete com- 
parison of the actions of a living body with those of a steam 
