In 1869, William Sellers, a prominent Philadelphia engineer partnered with Eli Garrett to start an iron foundry just north of Wilmington, Delaware. Sellers was perhaps best known for proposing a standardized system of screws, threads and nuts.
As the firm grew, a bridge fabrication division opened in 1873. It began working on significant projects, such as the deck of the Brooklyn Bridge.
During 1882, the company began enlarging the iron works, but did not complete the project until 1897. Sellers continued to remain president of the firm through the 1870s, 1880s and 1890s.
During the late 1880s, the Pegram Truss became a specialty of the company. Designed by George H. Pegram, these bridges were first patented in 1885, while he was working with Edge Moor.
The first bridge was fabricated for the Missouri Pacific Railway, to cross the Verdigris River in present day Oklahoma. The project was a resounding success. During his tenure with the MP, dozens of spans of this kind were built, including 20 in 1890 alone. His largest bridge constructed, located at Ft. Smith, Arkansas, saw 13 spans of this design constructed.
In 1893, Pegram left to work for Union Pacific Railroad. During his time with UP, dozens more of these designs would be built, particularly in places like Idaho. It appears that Edge Moor had the exclusive contract to build bridges for Pegram.
While most Pegram trusses have been demolished, there has been a push to preserve the remaining spans. 11 such spans still exist in Idaho, 2 in each Kansas and California and 1 in each Utah and Washington.
After Pegram left Union Pacific in 1898, work declined significantly for Edge Moor Bridge Works. As a result, the company merged into the newly formed American Bridge Company in 1900.
Despite this, Edge Moor Iron Company remained open, operating out of the excess space at the Wilmington location. The bridge plant was closed in 1925, and Edge Moor went out of business in 1936.
Edge Moor built a fair number of railroad bridges across the United States. Union Pacific and Missouri Pacific each appeared to have ordered dozens of Pegram trusses from Edge Moor, although a true number on how many were built will never be known. In addition, the Rutland Railroad in Vermont had Quadrangular Through Trusses constructed by Edge Moor, the Atchison, Topeka & Santa Fe used a number of Edge Moor Spans, and the Great Northern Railway, Chicago Great Western Railway, Chicago, Milwaukee & St. Paul Railway and Chicago, Burlington & Quincy all had significant river crossings constructed by Edge Moor.
A limited number of non-Pegram spans have been found to still exist on American railroads. There are undoubtedly more waiting to be discovered.
A sample of plaques and projects completed by Edge Moor Bridge Works can be seen below. Unfortunately, no plaques have been documented by the author on non-Pegram spans.
Downsville Railroad Bridge (Downsville, Wisconsin)
Minneapolis Pegram Truss Bridge (Minneapolis, Kansas)
Republican River Pegram Truss Bridge (Concordia, Kansas)