1150 MR. G. F. ROD WELL ON THE EFFECTS OF HEAT ON CERTAIN 
silver, and 58'5160 per cent, of the chloride and bromide of silver, which latter, from 
the heat point of view, may he regarded as the same substance, because their co¬ 
efficients of expansion are practically the same. It may he noted (vide below) that 
while the expansion of the bromide (which is slightly greater than that of the chloride) 
scarcely exceeds that of the iodide of lead, and while, moreover, the chlorobromiodide 
contains 8 per cent, more iodide of silver than the lead-silver iodide, the amount of 
contraction by heat of the latter is nearly four times greater than that of the former, 
although we must believe this effect to be solely due to the iodide of silver in each 
case. 
Comparison of the coefficients of the iodide of lead and the bromide of silver, used 
in conjunction with iodide of silver in the formation of the two compounds given 
below. 
Melting point. 
Iodide of lead. 
383° 0. 
Bromide of silver. 
427° C. 
Volume at 
d 
o 
O 
1-000000 
1-000000 
>3 
205 . 
1-015608 
1-021945 
ssr 
253 . 
1-019594 
1-027369 
J 3 
265 . 
1-027248 
1-028725 
JJ 
383 (solid) . . . 
1-048488 
1-042531 
33 
383 (liquid). . . 
1*078080 
3? 
427 (solid) . . . 
1-047855 
33 
427 (liquid). . . 
1-107225 
Comparison of the coefficients of the lead-silver iodide alloy with those of a 
chlorobromiodide of silver, and of iodide of silver. 
Lead-silver iodide alloy, 
containing 33‘794 per 
cent, of iodide of silver. 
Chlorobromiodide of 
silver, containing 4P484 
per cent, of iodide of silver. 
Iodide of silver. 
Composition. 
Pblg.Agl. 
AgI,AgBr,AgCL 
Agl. 
Volume at 
0° C. 
1-0U0000 
1-000000 
1-000000 
)J 
118. 
1-0036108 
. * 
y j 
124. 
1-0036108 
1-012037 
-998765 
5 } 
128. 
1-002314 
• j 
130. 
•999716 
)) 
131. 
■994517 
133. 
. -986717 
1-006637 
•998608 
/ * 
)) 
139. 
•984120 
•998503 
33 
142. 
•998450 
144. 
•984120 
J5 
144-5. 
150. 
•984810 
156-5. 
•980510 
300 . 
1-002060 
1-039239 
•989298 
Volume of 
solid at melting point . . 
1-013790 
1-046646 
1-005008 
44 
liquid at solidification point 
1-024370 
1-097486 
1-040908 
Melting point. 
350° C. 
331° C. 
527° C. 
