The 19th century was the age of machinists in our neighborhood. The 20th century saw the age of light industry including the manufacture of electrical components. Our history articles include one on the transformer plant at 18th and Callowhill; the International Brotherhood of Electrical Workers (IBEW) on Spring Garden Street; and even a mention of the Electrical Switchgear Union at 1836-1838 Callowhill Street. This article will discuss the biggest of them all.

An I-T-E circuit breaker made by Cutter as seen in a 1902 catalog on the left.
On the right is a modern circuit breaker made by Siemens, which owns and uses the I-T-E trademark on low-voltage equipment.
Circuit breakers prevent overheating of wires and fires. For more see outside link here with a 58-page explainer from Cutter in 1909.
In 1888, one Henry Cutter began making circuit breakers in a private residence at 27 South 11th Street. Older glass-enclosed fuses contain a strip of metal that melts and breaks the circuit, protecting against electrical fires when the current is too high for that circuit. After each fuse burnout, the fuse would have to be replaced. Cutter made mechanical circuit breakers to supersede the fuse. A current surge would mechanically pop a knife switch which opened the circuit. To "replace" the circuit breaker (after checking the reason for the trip) only a flick of the switch was necessary. In 1928 his company changed its name to I-T-E Circuit Breaker Company, derived from the term "inverse time element," which describes the mechanism of action in that the higher the current surge, the shorter the time interval to break the circuit. These types of mechanical circuit breakers, with smaller components, are in use today. For a witty I-T-E marketing booklet from 1915, see here.
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He moved westward to 1112 Sansom Street, then after he retired in 1891, the company moved to the northeast corner of 19th and Hamilton Streets. By 1946, a portion of the building at the future Tivoli site was being used by the I-T-E Circuit Breaker Company for administrative functions. I-T-E had taken over the former Baldwin Locomotive Works plant that was on the south side of the 1800 block of Hamilton and all the accessory buildings in the 1940s. In 1969 I-T-E Circuit Breaker merged with Eastman Imperial of Chicago to become I-T-E Imperial Company.

Photo from the 1920's of the Baldwin plant that was built in 1916 as a munitions factory. It would become a homeless shelter in 1931, then a warehouse, then the I-T-E factory.
The corner in the foreground is the northwest corner of the plant, making this view southeasterly looking at 19th and Hamilton Streets, right where the Baldwin Locomotive Works State historical plaque is located today.

Aerial photo from the southwest in 1928 showing the water tanks with BALDWIN painted on them atop the future I-T-E building. 1928 was the year that Baldwin Locomotive Works had completely moved to Eddystone.
Impressive resolution on this 1928 photo from a moving plane or zeppelin!

Portion of a map from 1922 showing automobiles and electricity replacing shoes and trimmings, as discussed in our article on the Graham and Laird factories. Baldwin Locomotive Works will be completely relocated to Eddystone by 1926.
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Composite image of two sections of the 1942 land use map.

Photo from 1946 of the southeast corner of Hamilton and 19th Streets.
The embossed name of the I-T-E Circuit Breaker Company has replaced the Baldwin signs.
Photo courtesy of the Free Library of Philadelphia.

Photo taken in 1946 looking northeast towards what is now Baldwin Park. The eight-story I-T-E building, the former Baldwin shop, dominates what is now the northern half of the park. A coal yard and other I-T-E buildings occupy the southern half. In the left foreground is 19th Street with its trolley tracks.
The Franklin Town project would demolish everything in this view.
Photo courtesy of the Free Library of Philadelphia.

Part of a Sanborn insurance map from 1951 (volume 4 plate 306).
I-T-E Circuit Breaker has taken over most of the future Tivoli site, and will eventually take over all of it. In this image the west side of Opal Street has been cleared of homes except for those fronting Hamilton Street and number 428.

Photo from the Inquirer of 26 July 1954 showing employees working on a low voltage switchboard.

Composite image of two sections of the 1962 land use map.
Baldwin Park in 2021 occupies the two acres that in 1962 were occupied by the U.S. of A. I-T-E Circuit Breaker Company. The Electric Equipment Company in the lower right made transformers, as discussed here.

In 1967 I-T-E had changed its name via merger to I-T-E Imperial and was headquartered at the current site of the Tivoli at the southwest corner of 19th and Hamilton Streets.
I-T-E owned a good amount of real estate in the neighborhood by 1971, and was one of the five partners in the Franklin Town Development Corporation, as discussed here. By this time I-T-E focused on distribution, transmission, and control of electricity, and manufactured hydraulics and fluid power systems. In 1976 I-T-E Imperial Corporation was acquired by Gould, Inc., and all of the I-T-E real estate was levelled between 1975 and 1985 for the Franklin Town Development project.
There were many acquisitions and mergers throughout the history of I-T-E, with a 1988 summary here . I-T-E is now mostly a part of Asea Brown Boveri.

Real estate holdings of I-T-E in 1971.
For a more granular, house-by-house, description of I-T-E holdings in the neighborhood see 80-page Park Trust Agreement of 1991 here
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