GAMEWELL SYSTEM

UPDATED AUGUST 2019

Fire alarm box and board at Denver Fire Museum

In 1876, the City of Denver installed a Gamewell Fire Alarm Telegraph system, consisting of eight miles of wire, two circuits and 18 alarm boxes.

Initially, the boxes were connected to a huge bell mounted atop a 150-foot tower. By counting the strokes, firefighters located the alarm. By 1890, the Gamewell system been expanded to 55 miles of wire and 95 boxes, and signals were transmitted by wire to Denver's firehouses. The system expanded as Denver grew and remained in service until 1971.

In its Dec. 29, 1906 edition, Fire Engineering reported:

"The fire alarm and police telegraph system of Denver—that of the Gamewell company—has cost over $200,000.

"In August, 1900, it was changed from a gravity battery to a storage battery system charged with 220 volts.

"The system is so arranged that, when any one of the 200 fire alarm boxes is pulled several things happen, the lights in every fire station in Denver arc automatically turned on the horses are automatically hitched, and, while this is going on, the gongs in every fire station, at the fire chiefs’ homes, newspaper offices, police station and many other places, sound the number of the box.

"Fifteen seconds after the pulling of a box, and sometimes sooner, the fire wagons are on the way to the blaze.

"The superintendent of the whole system, David Reed, is an expert electrician, who has had charge of it for over thirteen years."

By the 1940s, Gamewell systems were installed across Colorado: Aspen, Boulder, Canon City, Colorado Springs, Cripple Creek, Denver, Durango, Fort Collins, Golden, Greeley, Idaho Springs, Leadville, Manitou, Ouray, Pueblo, Salida, Sterling and Trinidad.

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DENVER: 700 BOXES, 33 CIRCUITS, MILES OF WIRE

Receiver with paper tape

In the 20th Century, the City of Denver was divided into five alarm zones:

1 - Central
2 - Southern
3 - Capital Hill
4 - Eastern
5 - Northern

Each fire alarm telegraph zone was divided into five sectors.

Each alarm box was assigned a four-digit identification number.

For example:

The fire alarm box at the corner of Colfax and Pennsylvania was assigned No. 1374.

"1" - The first digit identified the zone (Central).

"3" - The second digit identified the sector within the zone (Sector 3).

"7" and "4" - The third and four digits were unique to the transmitter of each box (Box 74).

In the 19th Century, when the city was less populated, each fire alarm box was assigned a two-digit identification number.

For example:

The box at 17th and Lawrence under the earlier system was numbered Box 27 and under the later system Box 1221.

SOURCE: Denver Firefighters Museum


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THE CIRCUIT:

BOX --> HEADQUARTERS --> REPEATER --> FIREHOUSE

Opening the door of an alarm box and pulling the hook would trip a clockwork motor. The motor turned a notched wheel unique to each box. The wheel broke an electrical circuit.

The notches on the wheel were arranged to send a signal identifying the alarm station to fire headquarters, which manually relayed the signal to firehouse receivers via a repeater.

The repeater tapped out the box number over a system of station bells several times. For example, the wheel for Box 27 would have been two notches, a space, and seven notches.

Firehouse bells would tap out the signal 2-7 for Box 27 in repetition, typically four times. A paper tape would also record the signal to verify the box number.

Firefighters would refer to a "running card" to determine in what order they were "due at the box," i.e. first, second, third, etc.