Chemistry and Physics. 267 
ily be reduced in small quantities from solutions of their chlorids. The 
author in the first place has found that the density of the current ex- 
not less important influence. As the unit of measure for the density of 
the current, Bunsen assumes the current having the absolute intensity 
I distributed upon 1 square millimeter. The intensity of the current 
was measured by a Weber’s tangent’s-compass, and reduced to absolute 
Measure by the formula I= er" tan. g, in which R is the radius of the 
ting in millimeters, g the deviation of the needle, and T the horizontal 
component of the earth’s magnetism expressed in Gaussian units. The 
Faraday’s lew, I=—, and this equation combined with the former 

. 
For the density of the current whose absolute 
intensity is I, the electrode having a section O measured in square mil- 

limeters, we have D r . 
ave D—=—= tan. g. Bunsen determines the quan- 
“oe: O- 220 Ms 4 
C. The error which arises from the catalytic recombination of the two 
pletely expelled. In overcoming pow 
mposing cell, one pole of which consists of the inner surface of a 
carbon crucible filled with chlorhydric acid, placed within a porcelain 
crucible and kept hot in a water-bath. A small earthenware cell within 
carbon crucible serves to contain the fluid to be decomposed. A 
harrow strip of platinum dips into this fluid and serves as the second 
battery pole, the current being compressed upon this to a great density. 
