644 
MR, EDWARD MATTHEY ON THE LIQUATION 
Gold and Aluminium. 
The interest of the problems connected with the liquation of alloys of the rare 
and precious metals, suggested the desirability of investigating the behaviour of a 
metal with a very high specific gravity alloyed with a metal with a very low one. 
For this purpose gold, which has a specific gravity of 19*3, and aluminium, whose 
specific gravity is 2'6, were selected. 
In order to show an absolute contrast, two alloys were adopted, viz.: — 
and 
K. Aluminium.90 parts, 
Gold. 10,. 
L. Gold . . 
Aluminium 
90 parts. 
10 
3 3 
The alloy K was the first one experimented with. The ten parts of gold were first 
melted in a crucible, and the 90 parts of aluminium gradually introduced, the alloy 
being stirred as each portion of aluminium was added. When the whole quantity of 
aluminium had been added to the melted gold, the crucible was withdrawn from the 
fire, the contents thoroughly stirred and cast into a spherical mould. This alloy was 
white and tough, but the fracture at the lower part of the hemisphere exhibited a 
purple-pink mottled appearance, of which more will be said subsequently. 
The specific gravity of this alloy was 2*89. The sphere was then cut into two 
equal halves from top to bottom. About I kilog. of the alloy was employed for this 
experiment. 
Alloy K. Aluminium 
Gold . . 
Parts in 1000 of gold— 
Outside. 
Intermediate. 
Centre. 
90-9 
76-1 
771 
93-5 
72 
107'5 
117 
144o 
113-8 
1010 
80-2 
Average . 104'4 
110-5 
Maximum difference in the gold between centre and mean of outside, 27 - 3 per thousand. 
Maximum difference in the gold between centre and mean of bottom of casting, 67'4 per thousand. 
900 parts. 
100 „ 
