COMPLETE FREEZING-POINT CURVES OF BINARY ALLOYS. 
39 
Table IIb. —Freezing Points of Alloys made by adding Silver to Lead. 
250 grams of Lead. 
(1-) 
Total weight o£ 
silver pi’esont. 
(2.) 
Percentage of 
silver. 
(3.) 
Atomic 
percentage of 
silver. 
(4.) 
Freezing point on 
the Centigrade 
■ scale. 
0 
0 
0 
327-60 
5-210 
2-04 
3-85 
306-17 
» 
(303-72) 
10-431 
4-01 
7-41 
(303-5) 
(303-2) 
15-647 
5-89 
10-71 
(303-2) 
20-862 
7-70 
13-80 
(30.3-4) 
26-078 
9-45 
16-67 
460-6 
31-293 
11-13 
19‘36 
481-6 
39-116 
13-53 
23-08 
505-5 
40-94 
15-81 
26-47 
523-6 
54-76 
17 97 
29-58 
536-9 
The second reading at 7‘41 atoms was taken on the day after the first. Until 
16’67 atomic per cents, of silver no higher point than the eutectic could be found 
although the alloys were heated above 500° C., and the cooling carefully watched 
until the eutectic point was reached. This must be due to the fact that very little 
solid separates out at the F. P. With more than this proportion of silver the F.C. 
could be detected, but the indication was slight until 23 atomic per cents, of silver. 
The eutectic point deduced from the above is 303'3°; in our previous work 
(‘Chem. Soc. Jour.,’ 1892), using mercury thermometers, we made it 303°, the fixed 
points on the mercury thermometers having been previously determined by com¬ 
parison with a platinum thermometer. 
