METALS AND THEIR ORES. 15 
In the drawing, the letters A A designate cylinders, each of which is constructed 
as shown in Figs. 3 and 4 of the drawing. Through the centre of each of these cylin- 
ders extends a rod, B, the ends of which have their bearings in sockets formed on the 
interior of the heads of the cylinder, and on this rod are secured the elements of a 
voltaic pile, C. All the copper elements of this pile are connected by a wire, a, which 
is in contact with one of the aT 3 Shoets~Shoet 2. 
heads of the cylinder, while Improvement in Voltaic Amalgamators for Gold and Silver. 
the zinc elements are con- No 123.932. Patentod Fob. 20, 1872, 
nected by a wire, @, which is 
in contact with the opposite 
head of said cylinder. By 
this arrangement I obtain a 
voltaic pile of great power in 
a comparatively small space ; 
but it must be remarked that 
one or more voltaic piles 
might be arranged in the 
interior of the cylinder in any 
desired position, and I do not 
wish to be confined to the 
precise arrangement of the 
voltaic pile which I have 
shown. Each of the cylin- 
ders A is provided in one 
side with a man-hole, through 
which the cylinder can be 
charged and discharged, and 
which can be firmly closed 
by a man-hole plate «. 
Through the side of the cyl- 
inder opposite the man-hole 
extends a pipe, @, which can 
be opened and closed by a stop-cock, ¢, and which serves to draw off the quicksilver 
at the proper time, as will be hereafter more fully explained. From the outer surfaces 
of the heads of the cylinders project gudgeons, e’, which have their bearings in the 
edges of a tank, D, which is intended to receive the pulp and conduct it to the agitat- 
ing-tub E. From the bottom of this tub rises a tube, 7, to a level with the top edge, 
and this tube forms the bearing for a vertical shaft, g, from which extend radiating 
arms #, carrying the agitators z, which extend down near to the bottom of the tub E, 
as shown in Fig. 1. In the side of this tub are three pipes, 7, one above the other, 
and each provided with a stop-cock; and from the bottom of the tub, just beneath the 
pipes 7, extends the discharge-pipe #, which leads to the first washer F. An enlarged 
