THE SPECIFIC HEAT OF BODIES. 569 
experimental vessel. The same current of elec- 
tricity must then be made to traverse two platinum 
wires immersed in the vessels; and the consequent 
increments of temperature must be carefully noted. 
As the capacity for heat of the standard vessel is 
in this case known, our equation 5 becomes 
id neat eye ho nein 6 
ni et: }bliee: 
where a is the weight of water in the standard 
vessel, including the water which is equivalent in 
capacity for heat to the vessel itself; r is the 
resistance of its platinum wire; and / the increase 
‘is the weight of water 
of its temperature: a 
equivalent in capacity to the experimental vessel ; 
b' the weight of the liquid under examination in 
the experimental vessel; 7’ the resistance of its 
platinum wire; and h' the increase of its tem- 
perature. 
When the specific heat of a fluid, capable of 
conducting the voltaic current, is to be determined, 
it will he proper to protect the wire from immediate 
contact with it. This abject may be accomplished 
by enclosing the platinum wire in a small platinum, 
or glass vessel, filled with water; or, instead of 
