Page:Proceedings of the Royal Society of London Vol 60.djvu/41

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On the Liquation of certain Alloys of Gold.
33

in gold, and with the clear indication thus afforded I proceeded to make the following experiments :—

On the Liquation of certain Alloys of Gold. 33 The alloy—

Z in c.................. 11-0 . Silver .............. 7'5 Gold.................. 81-5 100-0

and weighing 5-680 kilograms, was now alloyed by the addition of lead to produce a similar metal to P. 13 (see p. 25), say :—

Zinc..................... 10 Lead..................... 20 S ilv e r................. 7 Gold....................... 63 100

and this was cast into two spheres, a 2-in. sphere and a 3-in. sphere.

This alloy was so hard and brittle that I was compelled to cut these spheres into two by sawing them. When so cut asunder it was evident that the upper portions of both these spheres had a marked white appearance, as compared with the lower portions, which possessed the yellow colour of gold. The 3-in. sphere weighed 3'484 kilograms. Portions removed from these two spheres at the points indicated showed the following results Fig. 10.

G oid - coloured a f/cy

And those from the 2-in. sphere, weighing 0'880 kilogram —