The design evolution of “adjustable” (i.e., single-face) traffic signals across the major manufacturers in the first half of the 20th Century can be roughly classified into three generations:
- 1st Generation: Each full signal housing is cast as a single piece from top to bottom, or as two pieces with a full face attached to a full body, and with either bolted “porthole” style lens attachments or hinged doors.
- 2nd Generation: Each lamp module is cast as a separate piece, with open ends. These open modules can be stacked together in any number, as required. The stack (or individual module) is then enclosed by end plates at top and bottom and held together by tie rods through the length of the signal head.
- 3rd Generation: Each lamp module is cast as a separate, fully enclosed piece that can be stacked and bolted together in any number, as required. The stack (or individual module) comprises the signal head, with no need for tie rods or end plates.
The timeline below follows the history of the 3rd Generation design that was originally produced by Horni Signal Mfg. Corp. in 1938. The same basic design was then massively produced by The Marbelite Company after their takeover of Horni’s traffic signal division, from 1947 to 1978. After about a 20-year break, the same design was resurrected in the late 1990s by GTE Corp.
This timeline does not cover all the signal designs ever offered by these companies. For example, Marbelite’s 2nd Generation design that can be seen in this 1945 advertisement, and this photo detail from Philadelphia, is not in the scope of this document.
Horni Signal Mfg Corp. introduces their new modular signal design without need for end plates and tie rods.
The door edge sits in the signal body in a groove with a wick gasket. The lens portals are an inch deep. The Horni script logo is on back of modules. The term “Flat-Top” is sometimes used for these signals referring to the flush surface of the housing top and bottom. Cast ID is TD-19143. Modules are bolted together at the three points visible in the photos. I do not know what the dimples surrounding the bottom wire entrance hole were for. Perhaps Horni made a hardware fitting that mated with these dimples for adjustable positioning, but I haven’t seen such hardware.
Reflectors are heavy glass with a deep bowl shape. Reflector frames are 3-spoke casts hinged on the back of the doors. There is a brass retaining wire bolted to the door to keep the reflector frame secured behind the lens. Frames are embossed HORNI TC-19145 by the socket sleeve.
Horni Signal paused production of aluminum signals for a time during World War II and instead produced a fairly close facsimile made of Bakelite. These ultra-rare signals have been seen by a few contemporary collectors, including this light that still serves in East Rutherford, NJ. Horni would sell its traffic signal division to Marbelite shortly after the war.
The Marbelilte Company acquires the traffic division of Horni and continues to produce the pre-War Horni aluminum signal design.
Logo is now the block-lettered MARBELITE with no other verbiage. Cast ID TD-19143 H.S. is faintly embossed on the inside floor of the housing. This generations has the same thick glass bowl reflectors in 3-spoke frames hinged on the doors with the same brass retaining wire. The frames are now embossed TC-19145 by the socket sleeve (the word HORNI has been removed). The doors start out with the same non-lipped design as the original Hornis.
At some point in 1947 or ’48, a thin lip or flange was added around the door edge. The brass retainer wire on the lipped doors is a cane-shaped piece that is seated in the door frame, rather than bolted to it.
Marbelite introduces the “phantomless” optical unit, to reduce the reflection of ambient light from the signal. This is accomplished with shallower reflector bowls. The frames have a 4-spoke design with “Dzus” fasteners, a deep collar in front of the reflector so the mirrors are seated farther back from the lens.
Beginning of the “Patent Pending” Marbelites… Patent applied for 25 Feb 1950
PAT. PEND. and NEW YORK, U.S.A. verbiage added to logo. The reflector system has moved with this generation from the back of the doors to inside the housing. This design, or the specific implementation of it, was patented by Marbelite. The reflector frames swivel on a bent brass wire. Reflector shape is the same as before, and I believe this was probably the point when aluminum reflectors started being offered.
This is the generation when decorative end plates and tie rods were optionally offered, ostensibly to adhere to the specs of certain municipalities, like Baltimore. The end plates were merely attached to the top and bottom enclosed modules and were not a functional necessity. Signals with these parts are known by collectors as “Finned Marbelites” or “Marb Decos”.
The door shape changed at this time; There is a shallower lens portal (since the optical units have been moved back into the housing) and a slightly rounder profile to the raised corners. See the “Finned Marbelite” photo above as a reference.
The door shape changed again at some point to a “deep” profile with no lip, and with no hinge bosses across the face. This new door shape is the same or similar to the shape used in the next generation (see photos below).
The “Model 1058” is introduced, featuring the “sink top” (my term) design for improved drainage.
Cast ID TD-19260 is embossed on back inside wall of housing. The housing has recessed top and bottom with splined wire entrances and a rain notch in back. The deep, non-lipped doors are the same as (or similar to) the doors used at the end of the previous generation.
The housing shape and dimensions remain the same, but in a somewhat thinner cast. The drill points for bolts to hold sections together are gone in lieu of carriage bolts. The logo changed to down-slope parallelogram. Cast ID TE-19408 embossed on back inside wall of housing. The doors have a rubber gasket on the back (no gasket on the housing). The door shape is a smooth square with rounded corners and squared bases at the visor mounts. The reflector frames are spring-loaded, rather than sitting on a brass wire.
General Traffic Equipment (GTE) of Newburgh, NY acquired and resurrected the use of the Marbelite 8″ signal housing for a while starting sometime in the late 1990s, long after Marbelite ceased their signal production. These housings looked almost exactly like the Marbelite TE-19408 housing, but with at least one difference; the change in logo to the GTE logo. A representative of GTE told collector Steven Gembara that they stopped using these molds around 2014.
Special thanks goes to Joe LiPari of The Marbelite Company, who looked up the years of manufacture of the cast IDs for me in a phone conversation many years ago. Thanks also goes to fellow collectors like Phil Glick, Jay Jenkins, Larry Currie, Bailey Stumbaugh, Steven Gembara, and the late Jesse Vallely, for helping identify the minutae.