406 Learned Societies. 
deserts ; but he also was a Rabbinist. We stand upon the 
plain and unvarnished sense of the letter of Scripture, and 
we see no reason why the latter part of the passage, “ and 
ye shall bind them for a sign upon your hands, &c.,” should 
be construed literally, whilst the former part of the same 
passage “and you shall lay up these my words in your 
hearts and in your souls” must, of necessity, have a figu- 
rative meaning. |—Ep. TECH. 
LEARNED SOCI E(LES: 
ROYAL UNITED SERVICE INSTITUTION.—Several of 
the forthcoming evening meetings at the Royal United 
Service Institution, Whitehall, will be of particular interest 
in relation to naval affairs. On Monday evening last, Cap- 
tain. RK. A. E.. Scott, R.N., read a paper on * Vite ware 
ing of Iron Ships in a Seaway, and its Effects on Naval 
Gunnery ;’ on March 18th, Major W. Palliser lectures on 
“The Conversion and Rifling of Cast Iron Ordnance ;” 
and on April 15th, Captain Cowper R. Coles will discourse 
on “ The Turret versus the Broadside System.” 
ROYAL INSTITUTION.—On the 14th ult., in the course 
of a lecture upon sound, at the Royal Institution, Professor 
Tyndall exhibited for the first time a clever experiment 
devised by Biot, the French philosopher. By means of a 
polariscope made of rhombs of Iceland spar, placed in 
front of the electric lamp, the light was so polarised that 
none of it fell upon the screen. He -then fixed a strip of 
thick plate-glass, about three inches wide and six feet long, 
in a vice, and by rubbing it with a wet cloth made it give 
off a musical sound, because of the longitudinal vibrations 
set up. The vice bit the strip exactly in the centre, and 
there the strain and pressure of the musical vibrations were 
consequently greatest. But glass under strain or pressure, 
when introduced into the polarised ray, will let light pass 
through the polariscope. Consequently, when the ray was 
allowed to traverse this slip of glass near its centre, a broad 
disc of light appeared on the screen every time the glass 
set up.a musical sound ; but when the strip was at rest the 
calcareous crystals would allow no light to pass. en oes 
