[April, ’89. history society of Wisconsin. 
207 
These rods, if kept from action of the air during electrolysis, 
would last for forty-eight hours without much erosion. 
Carbon plates and cylinders were used, but the solid rods 
proved better in practice. 
It is stated in Watt’s Chem. Diet., under fluorine, that 
Cl displaces the F in any fluoride. In the preceding ex¬ 
periments Cl was certainly given off in large amount. 
The gases from the crucibles were allowed, however, to 
pass up the chimney, and I have as yet had no opportunity 
of analyzing them. I have used various basic linings for 
my clay crucibles, but alumina has thus far succeeded 
best. I tried some “ shrunk ” magnesia from basic steel 
works, but it contained so much iron that I could not use 
it. If free from Fe. it might answer very well. Lime can 
not be used as it fluxes very readily. 
Analyses of various samples of Al, obtained by the use 
of a Pb cathode, showed Al varying in purity from 75 to 
99 per cent. Silica was present in quantity varying from 
25 per cent, to a trace, and iron varying from 5 per cent, 
to a trace, and admixed Pb varying from 3 per cent, to • 
There was but little loss in the quantity of Pb, anc 1 
could be repeatedly used. 
The very low voltage and large quantity of metal ob¬ 
tained for a given number of amperes woulc seem 
promise much for this method of extracting • 
than a pound of Al to the electrical horse P° w er 01 
hours has been actuall} 7 obtained, and, undou te y, 
tinued experience will give a much better resn t. 
The best results, and in fact the only quantita 
suits that have yet been published, so far as am ’ 
for the separation of Al by electrolysis, are r ^ )<)r e - 
Dr. John Hopkinson of the Kleiner process, where 3 g • 
were produced to the 24 hours’ 
which would be about one-sixth of ^ 1 
