430 Scientific Intelligence. 
_ evaporation, at a temperature not exceeding 212°, may not suf- 
fice for the complete conversion of MgCl into MgO, LiCl remain- 
ing unchanged. Ignition would then remove the excess of 
ee the MgO, and the HgCl formed from the evaporated 
trate. é 
(To be continued.) 
SCIENTIFIC INTELLIGENCE. 
the current-intensity is the intensity of the current whose measurable ac 
tion under the conditions described is given by the equation 
iP D=t, 
This measure of current-intensity is at the same time the intensity of the 
current, which, when it flows around a plane of the unit of surface, 
at a distance an action equal to that of a magnet placed in the center of 
el having the unit of magnetism, and with its magnetic axis per 
pendicular to the plane; or it is also the intensity of the current by which 
al s-compass with a single circle of radius R is held in equilibrium, 
_ with a deviation from the magnetic meridian 
2 
: y = are tan pap : 
where T represents the horizontal component of the earth’s magnetism. 
: of the electr praeeee 
of acurrent are as follows: the same current passes through two circular 
