Page:Proceedings of the Royal Society of London Vol 60.djvu/35

This page needs to be proofread.
On the Liquation of certain Alloys of Gold
27

There is evidence of re-arrangement by liquation in this case which sends gold to the centre, but the result is complicated, as gravity appears also to send gold to the lower portion of the sphenca mass.

The foregoing mixture (No. 2) of On the Liquation of certain Alloys of Gold. G old............... 75 parts. Lead............... 15 » Z in c ............... 10 »»

was now further alloyed by the addition of 5 per cent, of pure copper and cast into a sphere which was very hard and brittle, and weighed about 2 kilograms. The following are the results at the points shown:—

Fig. 3. • 7575

Here again, gravity appears to send gold to the lower portion of the sphere.

The question arises, does the silver play any part in the distribution of the baser metals, lead and zinc ?

I therefore melted sphere No. 3 with 10 per cent, of silver, so that there were present:—

Gold . .. . ......... 63*4 (by difference) Silver............... 7*8 Copper.......... 5*1 Z in c ............... 8-8 L ead............... 14'5 Iron . . . r.... 0*4 1000

and cast into an open mould, and subsequently into the spherical mould. The following were the results obtained of fine gold at the points indicated:—