COMPLETE FREEZING-POINT CURVES OF BINARY ALLOYS. 
43 
Table IVb. —Freezing Points of Alloys made by adding Copper to Lead. 
Series 1.—250 grams Lead. 
(1.) 
Total weiglit of 
copper present. 
(2.) 
Percentage of 
copper. 
(3.) 
Atomic 
percentage of 
copper. 
(4.) 
Freezing point 
on the Centigi-ade 
scale. 
0 
0 
0 
327-6 
1-765 
-70 
2-26 
327-2 
4-965 
1-95 
6-10 
327-6 
24-29 
8-86 
24-10 
917-0 
26-44 
9-57 
26-70 
924-0 
29-44 
10-54 
27-80 
932-2 
34-46 
12-12 
31-06 
941-1 
37-58 
13-07 
32-94 
945-1 
41-81 
14-33 
35-35 
948-8 
46-83 
15-78 
37-97 
952-6 
51-98 
17-21 
40-47 
953-3 
>5 
326-9 
57-21 
18-63 
42-80 
953-7 
67 39 
21-23 
46-85 
954-5 
Series 2.—400 grams Lead. 
0 
0 
0 
327-3 
2-45 
•61 
1-97 
326-0 
21-96 
5-20 
15-24 
858-1 
30-04 
699 
19-70 
890-8 
The following numbers refer to the atomic percentage of lead in table IV. 
At *15 the stirrer set fast soon after the reading of the F.P. 
At ’32 there was much precipitate at or just after the reading, but stirring was 
possible. 
At 2'26 a very liquid substance was left on the surface after the bulk had 
precipitated, or been beaten down by the stirrer to the bottom of crucible. 
At 8'4, after the F.P,, a solid forms on the top, but it can be beaten down to the 
bottom of the crucible, until most of the alloy is solid, with some quite liquid at the 
top. 
At 17T3 no precipitate was felt for some time after the F.P. 
From 19T8 to quite 50 the temperature at the F.P. is, for some minutes, very 
constant, like that of a eutectic mixture. There is no perceptible precipitate at the 
F.P. or for some time after, and then it is noticed adhering as a layer to the walls of 
the crucible. 
