1877 -] 
Notices of Books. 
133 
Lessons in Electricity at the Royal Institution , 1875-76. By 
John Tyndall, D.C.L., LL.D., F.R.S. London: Longmans 
and Co. 1876. 
This little volume contains, with slight modifications, the 
substance of Prof. Tyndall’s Christmas Ledlures given to a 
juvenile auditory. We have been accustomed to go to the Royal 
Institution in order not only to hear the newest and most 
original matter in the world of science, but to see the most 
finished and elaborate apparatus ; to see the simplest things 
projected on the screen by means of the eledtric light, and to see 
the least wants and wishes of the ledturer anticipated by a host 
of ready assistants. But in the present instance it has been the 
aim of the ledturer to show how much can be done by means of 
the simplest and most inexpensive apparatus — a priced list of 
which is given at the end of the volume, the total amounting 
to £5 10s. 
“ I had heard doubts expressed,” says Dr. Tyndall in the 
Preface, “ as to the value of science-teaching in schools, and I 
had heard objections urged on the score of the expensiveness of 
apparatus. Both doubts and objedtions would, I considered, be 
most practically met by showing what could be done in the way 
of discipline and instruction, by experimental lessons involving 
the use of apparatus so simple and inexpensive as to be within 
everybody’s reach.” The Lectures are entirely confined to 
frictional electricity, and of this the book gives a very good 
elementary account, illustrated by many original and most 
ingenious experiments. 
The contrivances are always of the simplest, and can be made 
by any ordinarily ingenious person : sticks of glass, sealing- 
wax, and gutta-percha, a lath balanced on an egg ; a simple 
electroscope with Dutch metal leaves ; eggs for conical conductors, 
and apples for spherical conductors : these are some of the 
appliances of which the author makes use. We notice on p. 28 
a very ingenious experiment : a funnel with a stem of small 
bore is filled with fine silver sand, which runs out in a continuous 
stream ; but if a wire proceeding from a rubbed glass tube be 
connected with the sand in the funnel, the particles of sand fly out 
from one another as they descend by self-repulsion. We strongly 
and cordially recommend this capital little treatise to all boys 
who possess a scientific turn of mind, and they cannot do better 
than make for themselves the simple apparatus necessary for 
the performance of the principal experiments in the book, and 
then work through the book during the long winter days of the 
Christmas holidays. 
