Q 
REPORT — 1854 . 
turning the handle once, the number itself appeared ; by turning it twice every digit 
in it was doubled; and the result appeared above as twice the number originally wt 
and so on with any multiple of the number so set; then by moving the ivory balii 
simple multiple of 10 times, 100 times, 1000 times, the number set could be ob¬ 
tained and added to those previously obtuined, and thus the operation of multij-licat, , 
performed of any number by any number to the extent the machine could give, in 
this case up to 99,999,999 or nearly 100,000,000. The Professor then tamplifml 
this, by setting a large number and multiplying it by a number which consutrt 0 
three digits, lie then explained how the other operations were to be performed,— 
showing that the machine could add, subtract, multiply, divide, raise to an intc^r 
power, or extract the square or cube root with precision and rapidity. The price, 
the machine exhibited was .£*50. 
Prof. Wilson then, on the part of the Abb6 Moigno, presented anil explained B>. 
binet’s Homalographic Maps. In the maps on Mercator's projection, although tb 
relative geographical positions were accurately and simply laid down, yet there »»• 
a great distortion, particularly in those lands and seas towards and about the 1> - 
regions ; and the same remark was more or less applicable to all the ordinary pr 
jections used in maps. Put in those of M. Babinet, by making the principal meridian 
in both hemispheres straight lines, and the others, on each sideot them,arc « 
ellipses passing through the Polar points, and their ellipticitv varying with n 
position by a simple law, the exact harmony and proportion of the several part:, J 
and water, countries and places, on the map were correctly preserved when accuia 
laid down. M. Moigno presented to the British Association through this see "■ 
map of the world on this construction. 
Light, IIeat, Electricity, Magnetism. 
On a New Photometer. By M. Babinet, of Paris. 
th™»\ ph< ? , T e ! er C()nsistecl of a tube, at one end of which was a NicoU | 
wh, ch the light to be valued is admitted, the radiant or isource J 
t n K aC m at /. a Ineasuretl distance. As it passes along the tube the g ^ 
It then Unrf e ° f glass j jlatc3 through which, as it passes, it is polarize a l? 
its eS PaS t SeS 01 1 and is ™«ived It the eye-pieces ; another tube, 
Dlace57 W ’f a Nicol * s pris®. enters the side of this ft* ,, 
diIS,S d - at T h an ang,e as that light admitted from a standard sour 
through 13 , r . e ^ ected to the eve-piece by the same bundle of paialWei 
exact comnl Ch the f° rrac r light is refracted. By turning the 
oblong slits e [? entar y colours can be had from each source, and * * • 
crossed nn t w hicli the light passes, are made t° cross at the fjg 
the distinep frep frorn e itl>cr colour when the light to he j nstr un 
as that w) • r h ‘ Ch glves ^he same intensity to the light which ent f5 0 f i! 
distances Sv h frora the standard. A comparison of the squ kot 
distances g.ves the intensity of the light to be valued, in the usual aud* 
N lL° n / n tl the ^fraction of Transparent Media inchgj* 
%riti*h r< i ld FaCes> and 0,1 a Portable Bef lactometer, ed » Fg 
for lke Advancement of Science. By 
«eh N ard, of Bordeaux. , b , , v 
simple meE? ref [ a ? tion of P>«IW plates and liquids may be measured . 
TlZy t th ° Slewing principles.:- , nspare nt^ 
with parallel fad! trlv * P^P^'Culaily upon the surface of a 
P races traverses it without deviation. ^ 
the determhation'onbel^r “ nd P e a con,m «nication to the Acadeniyo f this .Vi' 1 
not been P ,ateS ’ but the "W"* 0- ^ 
