THE CONSTITUTION OF THE COPPER-TIN SERIES OF ALLOYS. 
21 
Freezing-point. 
Breaking-point. 
Pull-out. 
Copper. 
0 
1082 
o 
1084 
o 
Silver. 
961 
972 
— 
_ 
970 
— 
_ 
969 
— 
--- 
967 
— 
Aluminium .... 
655 
640 
654 
_ 
637 
654 
— 
630 
— 
Magnesium .... 
6.33 
644 
650 
— 
_ 
655 
— 
Antimony. 
6.30 
— 
630 
625 
Zinc. 
419 
426 
— 
_ 
426 
— 
Lead. 
327 
— 
332 
Bismuth. 
266 
— 
272 
Tin. 
232 
235 
235 
It will be seen from the table that, except in the case of aluminium, all the rods of 
metal broke at temperatures a little above the treezing-point. Ihis peculiarity oi 
aluminium is due to the fact that the metal has no constant tempeiatuie of 
solidification, but behaves more like a mixture than a pure substance. 
The apparatus was withdrawn from the furnace as soon as the weight fell, and the 
residue of the rod was examined. As a rule the rod had completely melted into two 
or three round beads, but the rod of aluminium broke without melting. 
The second method was a ijiill-out method similar to that employed by Meyer, 
Riddle and Lamb in the study of salts (‘ Ber.,’ 1894, Jahrg. 27, p. 3129), and later 
by us (‘Journ. Chem. Soc.,’ 1895, p. 190). A Jena tube of about 5 millims. internal 
bore was sealed at one end and the end slightly enlarged into a bulb. A gramme or 
two of the metal or alloy was then melted in the tube so as to fill the little bulb, and, 
while the metal was still liquid, an iron wire was pushed into the metal so that the 
end was immersed. When the metal had solidified, the iron wire became firmly fixed 
in the metal, and on account of the bulbous shape of the end of the tube the ingot 
was also fixed in the tube. The tube was then placed vertically, so that the lower 
end containing the metal was immersed in a bath of molten tin. The iqiper end of 
the wire projecting out of the tube Avas connected with a string passing ovei a pulley 
and stretched as before by a 50-gTanime Aveight. A pyrometer was placed in the 
bath of tin and the temperature sloAvly raised, until the Avire AAms pulled out of the 
metal. We called this the “ pull-out ” temperature. In some cases the end of the 
iron Avire \A’as bent mto a little hook before immersion in the metal, in othei cases 
the end Avas straight ; both gave the same results. The heating Avas not, as a lule, so 
slow as in the bar-breaking experiments, the time of heating not, as a rule, exceeding 
