Dahlgren, John Adolphus Bernard, 1809-70, American naval officer, b. Philadelphia. Appointed a midshipman in 1826, he had a long and honorable naval career. In charge of ordnance at the Washington navy yard after 1847, he expanded the ordnance facilities and designed the 9-in. (22.9-cm) and 11-in. (27.9-cm) guns that came to be called Dahlgrens. In the Civil War, Dahlgren received command of the Washington navy yard and soon became also chief of the Bureau of Ordnance. Promoted to rear admiral in 1863, he served as commander of the South Atlantic Blockading Squadron, cooperated (1863) with Gen. Q. A. Gillmore in the unsuccessful attempt to take Charleston, helped to place troops in Florida in 1864, cooperated with Sherman in taking Savannah, and in Feb., 1865, helped to occupy Charleston. He later held high posts and wrote widely on naval ordnance.

Rear Admiral John Adolphus Bernard Dahlgren, USN, (November 13, 1809 – July 12, 1870), son of Bernhard Ulrik Dahlgren, merchant and Swedish Consul in Philadelphia, Pennsylvania, made his career in the United States Navy. He headed the Union Navy's ordnance department during the American Civil War and designed several different kinds of guns and cannons that were considered part of the reason the Union won the war. For these achievements, Dahlgren became known as the "father of American naval ordnance."

Biography

John Dahlgren was born on November 13, 1809 in Philadelphia, Pennsylvania. He joined the United States Navy in 1826 as a midshipman and was promoted to the coastal survey in 1834. By 1847, he was an ordnance officer, and at the Washington Navy Yard began to improve and systematize the procurement and supply system for weapons.

Under his command, the Navy established its own foundry, and its first product was the Boat Howitzer, which was designed to be used on both ship and in landings. But it is his cast iron muzzle loading cannon which came to bear his name (the Dahlgren gun) and be his most famous contribution.

His "Boat Howitzer" design was an improvement on the shell-gun invented by the French Admiral Henri-Joseph Paixhans. Dahlgren wrote:

"Paixhans had so far satisfied naval men of the power of shell guns as to obtain their admission on shipboard; but by unduly developing the explosive element, he had sacrificed accuracy and range.... The difference between the system of Paixhans and my own was simply that Paixhans guns were strictly shell guns, and were not designed for shot, nor for great penetration or accuracy at long ranges. They were, therefore, auxiliary to, or associates of, the shot-guns. This made a mixed armament, was objectionable as such, and never was adopted to any extent in France... My idea was, to have a gun that should generally throw shells far and accurately, with the capacity to fire solid shot when needed. Also to compose the whole battery entirely of such guns." John A. Dalgren

The United States Navy had equipped several ships with 8-inch Paixhans guns of 63 and 55 cwt. in 1845, and later a 10-inch shell gun of 86 cwt. In 1854, the six Merrimack-class warships were equipped with 9-inch Dahlgren shell guns. By 1856, the Dahlgren gun had become the standard armament of the United States Navy.

However, fatefully, one of the "dahlgrens" exploded on being tested in 1860, causing Navy regulations to require the use of much lower levels of powder until 1864, well into the Civil War. The commander of USS Monitor felt that had his gunner packed the cannons with a full charge, he might have been able to destroy CSS Virginia.

Dahlgren himself took charge of the Washington Navy Yard in 1861, and in 1863 took command of the South Atlantic Blockading Squadron. In 1864, he helped William Tecumseh Sherman secure Savannah, Georgia. In 1869, he returned to the Washington Navy Yard where he served until his death.

The Naval station in Dahlgren, Virginia, Dahlgren Hall at the United States Naval Academy in Annapolis, Maryland, and several ships were named for him, as was Dahlgren, Illinois.

Admiral Dahlgren's son, Colonel Ulric Dahlgren, was killed during the Civil War in a cavalry raid on Richmond, Virginia, while carrying out an assassination plot against Jefferson Davis and the Confederate Cabinet. The plot is known as the Dahlgren Affair. The admiral was deeply troubled by his son's death and role in this event. Despite Radical Republican associations, John Dahlgren's younger brother Charles G. Dahlgren (1811-1888) was a strong proponent of slave ownership and was a Confederate Brigadier General, Commander of the 3rd Brigade, Army of Mississippi, which he personally funded.

Personal life

In 1865, Dahlgren married Madeleine Vinton, daughter of Congressman Samuel Finley Vinton and Romaine Madeleine Bureau, and the widow of Daniel Convers Goddard, first Assistant Secretary of the newly-created U.S. Department of the Interior. Madeleine was a well-known author in her own right. Their children were John Vinton Dahlgren, who married Elizabeth Wharton Drexel; Eric Bernard Dahlgren, Sr., who married Lucy Wharton Drexel ; and Ulrica Dahlgren, who married Josiah Pierce, and was the grandmother of Romaine Dahlgren Pierce, wife of David Mountbatten, 3rd Marquess of Milford Haven.

Selected works

• The System of Boat Armaments in the United States Navy
• Shells and Shell Guns
• Naval Percussion Locks and Primers

See also

• Dahlgren - Other uses of Dahlgren
• USS Dahlgren - List of US Naval ships named for Dahlgren
• Naval Surface Warfare Center Dahlgren Division

Notes

References

• Rear Admiral John A. Dahlgren. Biographies in Naval History. Naval Historical Center, Department of the Navy. Retrieved on 2006-07-24..
• Gayley, Alice J. Admiral John A. Dahlgren. Pennsylvania in the Civil War. PA Roots. Retrieved on 2006-07-24..
• Melton, Jack W., Jr. and Lawrence E. Pawl Admiral John A. B. Dahlgren (1809-1870). Civil War Artillery.com. Retrieved on 2008-08-16..
• John A. Dahlgren Collection. Syracuse University Special Collections Research Center. Retrieved on 2008-09-23..

Further reading

• Madeleine Vinton Dahlgren (1882). Memoir of John A. Dahlgren, Rear Admiral United States Navy. J.R. Osgood and Co.. ASIN B000895S0A. (Written by Dahlgren's widow)