John Griffen Of Safe Harbor, Pa., Was Inventor of Wrought Iron Gun
By Patrick McSherry

Summer 2000 - Vol. 22 No. 4


The Conestoga River bends and rolls through the pastoral hills and valleys of southern Lancaster County, Pennsylvania. Near its mouth, where it meets the mighty Susquehanna River, the Conestoga flows past the remains of the former boomtown of Safe Harbor.

Instead of the belching steam, smoke and the ceaseless noise of the rolling mills of years past, today's passer-by hears the sound of children playing at the baseball diamond or skating in the park. Here, about 150 years ago, the story was different. On a day in 1855, workers in the ironworks would have heard a new sound over the cacophony of factory noises. A roar had rent the air. Everyone knew what it meant — that ironmaster, inventor, and now cannon designer, John Griffin had just tested his first cannon.

John Griffen was born into a Quaker family in Mamaroneck, West Chester County, New York, in 1812. The following year, John's father passed away leaving John's mother, Esther, to support the family. Becoming a school teacher, Esther Griffen must have instilled an interest in learning within the young man.

He began his education under her tutelage, eventually attending a Quaker boarding school. His education focused on the subjects that would best help him in business, not engineering or metallurgy. By 1837, John had married Esther Leggett, and it was not until 1843, when John was already 31 years old, that he received his first introduction to iron-making. In that year he became the bookkeeper for the R.C. Nichols & Co.'s ironworks and nail factory in Norristown, Pa.

Only after beginning his work for R.C. Nichols & Co. did John Griffen's true genius for engineering and mechanical invention come to the forefront. Soon, his expertise apparent, Griffen was asked to erect an ironworks for Moore & Hooven, also of Norristown, where he used an ingenious system of reclaiming heat from the iron puddling furnaces to create steam to help run the plant.

In 1846 or 1847, John Griffen found himself standing on the banks of the Conestoga River. Iron had been discovered in the area and the company of Reeves, Archer & Co. was prompted to construct a new iron ironworks at that location to take advantage of the new find. John Griffen was commissioned to complete the task of building the new facility and soon moved to the area.

The new factory included a blast furnace, foundry and rolling mill. Eventually a company store was added, along with a clock tower and a village of 100 houses for the workers. The factory employed 250 people. Once the factory was completed, John was asked to stay on as the superintendent of the new works.

Soon, John Griffen's expertise was paying off. The new factory was turning out rails for the rapidly expanding Pennsylvania Railroad system. Griffen introduced a cost-effective governor which controlled the speed of the engines in the rolling mill, resulting in a more consistent product, and also replaced manpower with steam power in transporting the rails to be sawed.

Amidst the hustle of the boomtown that grew up around the ironworks, John and his wife Esther must have been a familiar sight. The couple attended the small Safe Harbor Methodist Episcopal Church, a small frame building, and the only church in the town. But in 1849, after only a few years at Safe Harbor, Esther died, along with their infant son, who also bore John's name. The couple had been married for 10 years and had four other children. Esther had been there to help John in his rise from bookkeeper to superintendent. Suddenly, she was gone.

For two years, John was alone. Presumably, during the mourning period John again grew close to his in-laws. His loneliness and familiarity with Esther's family evolved and his life began anew. In 1851 he remarried. His wife was Mary Leggett, Esther's sister.

The new couple had four children, three born while John was working at Safe Harbor, but all of the children were born in Philadelphia. Perhaps, since her sister probably died in child birth, she and John were leery of the dangers at the rural location and preferred to take their chances with medical service in Philadelphia. Their first child was named Esther L. Griffen in honor of John's first wife and Mary's sister.

In 1854, John began experiments on something new. His responsibilities at Safe Harbor frequently required Griffen to travel to Philadelphia. Here he had a discussion with a Major Bates serving with the Coast Survey. Apparently while discussing the relative merits of the brittle cast iron and soft bronze cannon then in use, the major suggested that a durable wrought iron be used instead.

Griffen considered the idea, and soon obtained the permission of the company owners for the construction of a prototype. The date was 1854. In the same year, the Safe Harbor works were ordered to be doubled in size.

John Griffen's process for manufacturing the new wrought iron cannon was as follows:

"A pile of wrought-iron rods 7/8" x 7/8" x 4 1/2" were welded together to form a mandrel. A long bar 3/4" x 4 1/2" was wound spirally around this by revolving the lathe. Three successive layers were thus applied to the mandrel, each layer spiraling in a direction opposite to the previous one. A thin layer of staves was applied to the outside, and a plug driven to form the breech. Welding heat was then attained and the mass was rolled out to the length of seven feet. Trunnions were welded on and the gun was bored and rifled from the solid."

The result was a gun of incredible strength but relatively light weight. Griffen's rolling mills, with his modified governors and smooth operation, were able to turn out the new gun with a reliability that had not been available before. After all, one of the last notable attempts at a wrought iron gun, the "Peacemaker" aboard the Princeton, resulted in disaster in 1844, with the secretary of state and secretary of the navy being among the eight killed when the gun failed.

By 1855, the new gun was ready to be tested. Soon, the river hills were resounding to the roar of the cannon's breath as Griffen tested his gun. Once he was satisfied, Griffen patented his gun in December of that year.

The story of the gun's testing by the government is well-known and often recounted; however, it can plainly be stated that the gun was a resounding success. The gun was tested until failure, which occurred only after the standard test of 500 rounds fired, with failure only occurring after seven pounds of powder and 13 projectiles were used in the gun!

In 1856, John Griffen was moved by his company from Safe Harbor, his home for nearly 10 years, to Phoenixville, Chester County, Pennsylvania. Here he operated the Phoenix Iron Works and even served as a town burgess and a member of the school board.

While John Griffin moved onto next invention — a process to make iron beams — the Phoenixville Iron Works turned out hundreds of Griffen guns for the war effort. Griffen would remain at Phoenixville until 1862. In that year, Griffen left this position to work for the Buffalo Union Iron Works, only to return to Phoenixville in 1867. He became the general superintendent of the works and one of the firm's directors. He also worked with the related bridge-building firm of Clarke, Reeves & Co.

John Griffen passed away on Jan. 14, 1884. By that time, Griffen's famous Safe Harbor Iron Works were also fading away, eventually disappearing entirely. Safe Harbor is now virtually a ghost town in comparison to its size in John Griffen's day. A baseball diamond sits on the site of the rolling mills.

Still, there is one reminder of the presence of the brilliant John Griffen. On a small hillside behind the Safe Harbor United Methodist Church, just a short distance from the Conestoga River, there is one marker. It bears no evidence of Griffen's brilliance, his ingenuity, or his invention of the Griffen gun. Instead it tells the story of a man's inner heartbreak and of sadness. The tombstone simply reads "Esther L., Wife of John Griffen, Departed This Life April 16, 1849, Aged 30 Years, Also Their Infant Son John."

[Editor’s Note: John Griffen’s gun, officially known as the 3-Inch Wrought Iron Rifle, was modified by the Ordnance Board in 1861 so that it would fit standard carriages and weigh less. The modified gun was known as the 3-Inch Ordnance Rifle and incorrectly termed a “Rodman Rifle” by some. The Artilleryman magazine’s original research on the cannon which was published in 1982 will be reprinted in an upcoming issue.]


(About the Author: Patrick McSherry is an architect and architectural engineer. He is the editor of the Spanish-American War Centennial Website at and the author of many historical andanthropological articles. He is involved in Civil War and Spanish-American War Living History.)