44 TlMEHRI. 
operator on the windward side, one of the small sodium 
cubes is by means of a wire placed on the mercury. 
A flash follows and some of the mercury is volatilized ; 
another cube is put in the same place until after three or 
four cubes have been used, the sodium will sink quietly 
without any flash. At the proper moment, a solid mass of 
amalgam will be observed in the centre when the contents 
may be safely stirred, and the addition of a few more 
cubes of sodium will change the whole to a mass of 
crystals of sodium amalgam which can be put into closely 
stoppered glass bottles — without any addition. A 
bottle should hold what is wanted at a time, since when 
opened the residue spoils. 
Many of the Californian mines which were abandoned 
long ago when methods of mining and milling were in 
their infancy, and when proper machinery, water power, 
&c, were hardly obtainable, have been worked over with 
satisfactory results. At one time it was thought that 
auriferous stone would only be found in paying quantities 
near the surface ; but it is the case that " paying rock" is 
now met in the deep workings of the Californian mines, 
and that the best dividend-paying mines are getting their 
rock from depths of from one thousand to fifteen hundred 
feet. Mr. Melville Attwood of San Francisco, 
a practical gold miner of long experience, believes that 
every increased foot in depth at which paying quartz is 
found, means prolonged permanency of the gold produc- 
tion of the district. That this is the case with Australian 
mines, is shewn by the returns from six of these quoted 
by Mr. ATTWOOD. 
Many Californian mines have been abandoned when 
zones of poor quartz have been met, where, had the 
