TYPE D SIGNALS
The Type D signal was introduced sometime
around 1936. This signal design was considered a
new design keeping with the trend of modern
design. The four illustrations on this page show
the artistic lines of the signal. The straight line
motif is carried out in the entire signal. Hinges and
catches are concealed, and as a result, the signal
presents an excellent appearance when viewed
from any angle.

The casing, door and hood are made of a special
silicon aluminum alloy, cast in steel dies under
tons of pressure. Such construction insures a
uniform and homogeneous casting of great
strength, capable of resisting corrosive
atmospheres, including salt air. Castings are
extremely accurate and all joints fit to a few
thousands of an inch. Similar parts are
interchangeable on all signals.

The bodies of the type D signal are of unit,
sectional construction-an individual body casting
being used for each optical system. These
individual body sections are clamped between
ornamental end plates by means of two 3/8"
through bolts, thus insuring a rigid, compact
casing which is dust and watertight. Signals of
one, two, three, four or five sections may be built
up as desired.

This unit construction, with complete
interchangeability of parts, is of great benefit to
cities using any quantity of signals, since any
desired combination and arrangement of signal
bodies can be made up locally. In case of damage,
there is considerably more salvage with this unit,
of sectional construction, than with any other
type. Door and hood are cast in one piece, which
saves assembly on the job. Doors with separate
hoods of sheet aluminum could have been
furnished on special order.

After assembly, the complete body is finished
with two coats of baked enamel, thus affording
additional protection against the weather.

MORE INFORMATION AND PICTURES WILL BE DISPLAYED SOON.