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78 The Frog War and M&S Demise

Railroads were a growing industry in the 19th century, and Blawenburg was served by the 25-mile Mercer & Somerset Railroad (M&S). However, on January 29, 1880, the Monmouth Democrat reported that effective January 21, 1880 the M&S, serving Blawenburg and other local communities, ceased operations.

From the Monmouth Democrat

That’s the end of the story, but where did the M&S run? Where was the Blawenburg Station, and what led to the demise of not just the Blawenburg Station but the entire M & S line? The answer to these questions reveals a story involving competing railroads, politicians, money, and even a war.


To understand the context of the story, we must examine the state of the railroad industry following the Civil War. Until the advent of railroads, materials, merchandise, and people moved distances on waterways or horse powered transportation. The use of canals to move goods and materials between rivers became popular in the 1800s. At their peak in the second half of the 19th century, there were over one hundred thousand miles of canals in the United States. These canals diminished in importance and use as the railroad industry grew. Rail transportation was cheaper, faster, and more direct.

New Jersey, being located between the ports in Philadelphia and New York, was a prime location for the development of railroads to move goods and people between these major markets. Small railroad lines connected with other railroads to move cargo from New York, Jersey City, South Amboy and other ports along the east coast to Philadelphia and vice versa.

In 1832 as railroad companies began to increase, the New Jersey legislature passed a charter, undoubtedly lobbied by existing railroad companies, forbidding the development of new rail lines in the proximity of existing lines without the permission of existing companies. The Camden & Amboy (C&A) was a major railroad that ran lines from the Delaware River in Camden to the ports at the Amboys where the Raritan River flows into Raritan Bay and then the Atlantic Ocean. They built several spur lines, one of which became the backbone of the today’s northeast Amtrak line. This charter was regarded as a legislated monopoly that favored the C&A, but it expired in 1867 after 35 years. This opened the door for other rail lines to be built between these major cities. By 1869, a plan was developed to link smaller lines together to form a National Railway between New York and Washington. Rail lines in New Jersey were critical to this plan, and C&A was in a position to use some of their existing lines and new lines to continue their monopoly and form the backbone of the national railway in New Jersey.

The C&A decided to build a new rail line called the Mercer & Somerset. It ran from the junction of the Delaware Belvidere Railroad, just south of Washington Crossing, NJ, to the junction of the Millstone & New Brunswick Railroad.

Competition was now possible, and soon, another company, Delaware and Bound Brook Railroad (D&BB), was formed to go from Bound Brook, near Somerville, to the Delaware River, not far from the termination of the M&S line. The D&BB Railroad was leased to the Philadelphia and Reading Railroad, which ran its operation. It had plans to connect with an existing line across the river, the North Pennsylvania Railroad, to connect the rail line to Philadelphia. This was a test of the coexistence of railroads owned by major railroad companies. As we shall see, the test didn’t go so well.

Blawenburg Station

The M&S Railroad cut a diagonal path through Montgomery crossing Skillman Road and passing through the James Van Zandt property (SAVE animal shelter and Montgomery High School today). The railroad claimed the right of way, and a station was built on the Van Zandt land in the general area of the high school parking lot. Little is known about the station. The first trains rolled over the completed line - from Millstone to Somerset Junction on the Delaware River on February 6, 1874.

This 1874 map shows the M&S cutting through Montgomery Township near Blawenburg. Note the name J. (James) Van Zandt just south of the railroad and the three building symbols above his name. The mark below the R of Mercer is closest to the rail line and is likely the Blawenburg Station. The competing D&BB isn’t on this map, because it was constructed in 1876. The red line represents its path.

The M&S had financial problems from the start, showing a loss in most years. In its only profitable year, 1875, it made $637.16. Even in those times, that was too little to sustain a railroad.

The M&S was completed as the D&BB was building its lines. Southwest of Hopewell Borough, the new D&BB line had to cross the M&S just east of Van Dyke Road. The crossing point of the two lines was known as a frog. (See the frog pictures below.) This meant that if there were two trains coming on different lines, one would have to wait while the other train crossed through the intersection. A frog in railroad lingo is the intersection of two rail lines that enables trains to cross from either direction.

There are two types of railroad frogs. The diamond frog pictured below shows one rail line splitting into two, allowing trains to go on either branch of a rail line. Some thought that the intersection resembled a splayed frog on the horse’s hoof as pictured below.

While having nothing to do with a rail intersection, the horse’s hoof provided the frog’s name, and it soon became associated with any rail intersection.

L - a diamond frog. R - the horse’s hoof from which a diamond frog was named.

The Frog War

On January 5, 1876, a “war” between the two railroad lines occurred at the M&S/DBB frog in Hopewell. It became known as the Frog War.

The actual site of the Hopewell frog, the scene of the Frog War. The lines at this frog crossed each other at 90 degree angles with the lines perpendicular to each other.

Disagreement, desire to dominate, greed, and many other negative human qualities can lead to anger and even war. History is replete with examples of this.

The Frog War started when the D&BB rail construction approached the area where they needed to cross the M&S track. M&S objected to the crossing. D&BB knew there would be a problem, and they were fighting M&S’s objection to the frog in court.

The D&BB locomotive crashed into the M&S guarding engine at the Hopewell frog.

To prevent the installation of the frog, M&S put a guarding engine right on the spot where the D&BB rail line was to intersect their line. When their own train came through, the guard engine was moved to a siding to let it through. Then it returned to block the construction of the frog. D&BB saw what was happening and decided to act.

On the night of January, 5, 1875, 200 men mobilized in a nearby cornfield and waited for the guard engine to pull off to a siding to allow an M&S train to go by. The men quickly attacked the guard engine, putting ties and other timbers between its wheels and chaining it to the tracks. They then quickly put the frog in place and brought their own engine to the spot. The M&S reacted quickly, sending a telegraph to Millstone to get another locomotive to Hopewell to ram the D&BB engine. The engine came and rammed the D&BB engine. Before much more damage could be done, the NJ National Guard was deployed to the scene. As one observer noted, “by morning nearly fifteen hundred people had gathered, many of them armed, especially the farmers, with squirrel rifles, smooth bore muskets, and some with the old King’s Arm flintlock of the revolution.” Governor Joseph Bedle intervened and further violence was averted. An injunction was secured and quick action was taken to give D&BB formal permission to cross the M&S line. Fortunately, no one was killed or injured.

Imagine what a sensation this would be today on social media and streaming newscasts 24/7!

Back to the End of the Story

The Frog War signaled the end of the M&S. It survived for another three years, but it went bankrupt on November 28, 1879. It had its final run on January 21, 1880. Shortly thereafter, its tracks were torn up leaving little evidence of its existence.

Along with the demise of the M&S came the abandonment of the Blawenburg Railroad Station. It was moved closer to the new nearby Reading line and finally razed in 1930. Later, the current rail line in Montgomery was built, and the Skillman Station was built along the new line not far from the old Blawenburg Station. It, too, no longer exists.

L – These are two of the few remaining sights of the M&S still visible in Montgomery. The photographer who took this picture in 2008 was standing on Skillman Road opposite Wessex Lane looking south west. The "fill" where the tracks used to be is just starting to bend to the right towards the present-day high school. In the distance you can see the trees of Skillman Park.

R - The remnants of a bridge where the railroad crossed Rock Brook. Today, this is in the development off Van Zandt Road in the western part of Blawenburg.

Were it not for the Frog War, the story of the short-lived M&S Railroad and Blawenburg Station might be forgotten.


For more information

1. A YouTube presentation by the Hopewell Valley Historical Society about the Frog War



1. It is believed that the sole purpose of the construction of the M&S was to impede the construction of the National Railway.

2. Somerset Junction is where the M&S connected with the Belvidere Delaware in Ewing Township. Today it is better known as the intersection of Rt. 29 and Jacobs Creek Road. The entire length of Jacobs Creek Road was the original right of way/road bed of the M&S.

3. Only one station along the M&S route exists today. The Pennington Station is near the intersection of Route 31 and Delaware Avenue in Pennington.

4. A sign near the old Hopewell Railroad Station recalls the Frog War Story.




Thanks to Ken Chrusz, who made me aware of this story and provided information and images for this blog.

“Clues from Hopewell Valley’s Long Lost Railroad.” Hopewell Valley Historical Society Newsletter. Vol. XXVI, No. 2, Fall 2007, Page 507

Kilbride, John. The Mercer & Somerset Railroad, and a Frog War! Issue 31, March 2016.


Monmouth Democrat news clip – public domain/K. Chrusz

1884 map of Blawenburg – public domain/K. Chrusz

Diamond frog – Wikipedia Commons

Horse hoof – Wikipedia Commons

Locomotives crashing – public domain

Railroad area filled –, Kim Piersol

Railroad near Van Zandt Road -, Kim Piersol

Frog War sign – D. Cochran


Editor—Barb Reid

Copyright © 2022 by David Cochran. All rights reserved.


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