Company. It is fitted with
a Pickering governor for constant speed. The engine is capable of
delivering (with condenser) 1,200 indicated horse power, and without
condenser 250 indicated horse power less.

With steam at 170 lb. pressure the engine worked at 350 revolutions
per minute, but it has been rearranged so as to deliver 700 indicated
horse power with 160 lb. steam pressure without condenser, and at 300
revolutions per minute:

The high pressure cylinder is 141/2 inches diameter.
" intermediate " " 25 " "
" low pressure " " 32 " "
" stroke is 16 inches.

The dynamo for producing the requisite amount of electric current
supplied to the furnaces is one of the well known Elwell-Parker type
of alternating current dynamos, designed to give 400 units of
electrical energy, equivalent to 536 indicated horse power.

The armature in the machine is stationary, with double insulation
between the armature coils and the core, and also between the core and
the frame, and is so arranged that its two halves may be readily
connected in series or in parallel in accordance with the requirements
of the furnaces, e.g., at an electromotive force of 80 volts it will
give 5,000 amperes, and at 160 volts, 2,500 amperes when running at
300 revolutions per minute.

The exciting current of the alternator is produced by an Elwell-Parker
shunt wound machine, driven direct from a pulley on the alternator
shaft, and so arranged as to give 90 amperes at 250 volts when running
at a speed of 800 revolutions per minute. From 60 to 70 amperes are
utilized in the alternator, the remainder being available for lighting
purposes (which is done through accumulators) and general experimental
purposes.

The process is carried out in the following way: The raw materials,
all intimately and carefully mixed together, are introduced into the
furnace and the current is then turned on. Shortly afterward,
indications of phosphorus make their appearance.

The vapors and gases from the furnace pass away to large copper
condensers--the first of which contains hot and the second cold
water--and finally pass away into the air.

As the phosphorus forms, it distills off from the mixture, and the
residue forms a liquid slag at the bottom of the furnace. Fresh
phosphorus yielding material is then introduced at the top. In this
way the operation is a continuous one, and may be continued for days
without