close the exhaust pallet C|2|, thus allowing compressed
air to rush from the box A into the motor B and so cause this latter
motor to open and (through the medium of the pull down P) to pull the
soundboard pallet from its seat and allow wind to pass into the pipes.

[Illustration: Fig. 7. Valve and Valve Seat, Hope-Jones Electric
Action]

The valve-seat H has formed on its lower surface two crescent shaped
long and narrow slits. A very slight movement of the armature disc J,
therefore, suffices to open to the full extent two long exhaust
passages. The movement of this disc is reduced to something less than
the 1/100 part of an inch. It is, therefore, always very close to the
poles of the magnet, consequently a very faint impulse of electricity
will suffice (aided by gravity) to draw the disc off the valve-seat H.
The zinc plate K being in intimate contact with the iron poles of the
magnet N, protects the latter from rust by well-known electrical laws.
All the parts are made of metal, so that no change in the weather can
affect their relative positions. R is the point at which the large
motor B is hinged. G is a spring retaining cap in position; O the
wires leading from the keys and conveying the current to the magnet N;
Q the removable side of the box A.

Fig. 7 represents a larger view of the plate K in which the magnet
poles N are rigidly fixed--of a piece of very fine chiffon M (indicated
by a slightly thicker line) which prevents particles of dust passing
through so as to interfere with the proper seating of the soft Swedish
charcoal iron armature disc J--of the distance piece L and of the valve
seat H.

On the upper surface of this valve seat H another piece of fine chiffon
is attached to prevent possible passage of dust to the armature valve
J, from outside.

As all parts of this apparatus are of metal changes in humidity or
temperature do not affect its regulation.

The use of this action renders it possible for the console (or
keyboards, etc.) to be entirely detached from the organ, moved to a
distance and connected with the organ by a cable fifty or one hundred
feet or as many miles long. This arrangement may be seen, for example,
in the College of the City of New York (built by the E. M. Skinner
Co.), where the console is carried to the middle of the platform when a
recital is to be given, and removed out of the way when the platform is
wanted for other purposes.

As all the old mechanism--the