bout 48 inches long.

The head of the electrode is screwed to the copper rods or "leads,"
which can be readily connected with the flexible cable supplying the
current.

The electric furnaces are rectangular troughs built of fire brick,
their internal dimensions being 60 in. x 20 in. x 36 in. deep. Into
each end is built a cast iron tube, through which the carbon
electrodes enter the furnace.

The electrodes are so arranged that it is possible by means of
screwing to advance or withdraw them from the furnace.

The whole current generated by the great dynamo of the Cowles Company
was passed through the furnace.

In the experiments raw materials only were used, for it was evident
that it was only by the direct production of phosphorus from the
native minerals which contain it, such as the phosphates of lime,
magnesia, or alumina that there was any hope of superseding, in point
of economy, the existing process of manufacture.

In the furnaces as used at Milton much difficulty was experienced in
distributing the heat over a sufficiently wide area. So locally
intense indeed was the heat within a certain zone, that all the oxygen
contained in the mixture was expelled and alloys of iron, aluminum,
and calcium combined with more or less silicon, and phosphorus were
produced. Some of these were of an extremely interesting nature.

We now turn to a short account of the works and plant which have been
erected near Wolverhampton to prove the commercial success of the new
system of manufacturing phosphorus.

The ground is situated on the banks of a canal and extends to about 10
acres, which are wholly without buildings except those which have been
erected for the purposes of these industrial experiments. These
consist of boiler and engine houses, and large furnace sheds.

There are three Babcock & Wilcox steam boilers of 160 horse power
each, and each capable of evaporating 5,000 lb. of water per hour. The
water tubes are 18 ft. long x 4 inches diameter, and the steam and
water drums 43 in. in diameter and 231/2 ft. long, of steel 7/16 ths.
in. thick, provided with a double dead head safety valve, stop valves,
blow-off cock, water gauges, and steam gauge.

The total heating surface on each boiler is 1,619 square feet and the
total grate surface is 30 square feet.

The boilers are worked at 160 lb. pressure.

The engine is a triple compound one of the type supplied for torpedo
boats, and built by the Yarrow Shipbuilding