42 
MESSRS. C. T. HETCOCK AND F. H. NEVILLE ON 
would expect these readings to be subject to a large experimental eri’or, but the 
curve shows that they are consistent with each other. 
It will be noticed that where the two series meet the latter lies some five decrees 
higher. The discrepancy may be due to some small extent to a change in the 
constants of the pyrometer, to a greater extent to an error in the determination of 
the last F.P. of the first series, but we think it is also due in part to a loss of silver 
1)y volatilization and splashing during the course of the first series. 
Table IVa. — Freezing Points of Alloys made by adding Lead to Copper. 
Series 1.—200 grams Copper. 
(1.) 
Total weight of 
lead present. 
(2.) 
Percentage of 
lead. 
(3.) 
Atomic 
percentage of 
lead. 
(4.) 
Freezing point 
on the Centigrade 
scale. 
(5.) 
Atomic fall. 
0 
0 
0 
1080-8 
1-00 
■50 
■15 
1079-3 
10-0 
2T22 
1-05 
■32 
1077-1 
11-6 
5T24 
2-50 
■78 
1071-6 
11-8 
10T24 
4-82 
1-55 
1062-8 
11-6 
15T24 
7-03 
2-26 
1055-1 
11-37 
25T2 
11-16 
3-70 
1039-2 
11-25 
40T2 
16-71 
5-78 
1018-3 
10-81 
60T2 
23-11 
8-42 
995-0 
10-19 
80T2 
28-60 
10-92 
977-6 
9-45 
105T2 
34-45 
13-86 
963-6 
8-46 
135T2 
40-32 
17-13 
954-4 
155']2 
43-68 
19-18 
953-3 
175 12 
46-68 
21-13 
953-1 
195T2 
49-38 
22-99 
953-1 
215T2 
51-82 
24-76 
953-2 
Series 2.—96 grams Copper. 
104 
52-01 
24-90 
951-1 
164 
63-08 
.34-33 
952-3 
254 
72-58 
44-73 
952-0 
.394 
80-41 
55-67 
951-2 
424 
81-54 
57-47 
9.50-8 
