Se eS 
9-0 6 F 
A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 
“To the solid ground 
Of Nature trusts the mind which builds for aye.",—Worpswortn. 
NO. 2302, VOL. 92] THURSDAY, 
DECEMBER 1, 
1913. [PRICE "SIXPENCE 
Kegistered as a Newspaper at the General = Office. ) 
~ (All Rights Res-rved: 
Wheatstone’s Compound Gyroscope 
PACKED IN CABINET CASE. 
Simple Cyroscopes 
from 10/6 
Telegrams : 
“ Newtobar 
London.” 
Illustrated’ Price List of Gyroscopes 
to be had post free from 
NEWTON & CO., Opticians to H. M. King Ceorge V. 
72 WIGMORE STREET, LONDON, w. 
STUDY 
tHe LENS 
It is the Key to Success in Photography. 
Established 
over 200 Years, 
Who can expect to excel who does not understand 
how to use the diaphragm, the swing back, the 
rising front, focussing scale, &c., &c.?) All such 
questions are lucidly and simply explained in 
PHOTOGRAPHIC LENSES 
A SIMPLE TREATISE.” 
350 pages, 44 plates, numerous diagrams and 
illustrations, cloth bound. 
R. & J. BECK, Ltd., $2, SO2sHIxL, 
REYNOLDS & BRANSON, Ltd., 
Manufacturers of Chemical cat 
Physical Apparatus. 
GRAND PRIX AWARD, 
THE “ RYSTOS ss 
ELECTROSCOPE. 
This Electroscope, with paraffin 
insulator, will retain its charge for 
a day, and has been used with 
the greatest satisfaction in many 
secondary schools for the last ten 
years, A customer states that the 
batch of two dozen, obtained 
{==y two years previously, has re- 
mained in efficient condition 
during that time. 
(a) Price with attachment for two Wires and top re- 
movable for cleaning the glasses.. S/- each. 
(6) Ditto, with two glass tubes for showing the leak- 5/6 each 
age caused by a radio-active gas.. J 
(c) Ditto, with transparent scale, lecturer's pattern, 
for projection of image ei eels leaf and scale > '7/G each. 
by means of a lantern... 
14 COMMERCIAL STREET, LEEDs. 
a 
Write 
for Price 
List of 
** Gifla.) 
Many of our Scientific Instruments 
handsome, and acceptable 
GIFTS. 
Recording Barometers from £4 4s. to'£27 10s. 
NEGRETTIL_ G&G ZAMBRA, 
38 Hol based Vidaaiee, Db don, E.C. 
ity ‘Branch: 45 Coy, 
/West End: 122 Regent 
are useful, 
