Developed and designed by American Naval Officer John Dahlgren in the 1860s, he was inspired by an accidental explosion of a cannon he witnessed during The Mexican-American War. Poorly made and overcharged gun barrels were a problem in military service. Dahlgren set about to develop a weapons system that would revolutionize how cannon were constructed. Cast in a smooth, rounded shape, the barrels resembled "soda bottles". This shape was important due to how it pulled away the explosive gases from the initial charge. Made in smoothbore and rifled, Dalhgren also perfected a form of shell that featured a low and flat trajectory impact for use with his guns. His smaller designs were used to create The Boat Howitzers. These were specialized raft-like boats (that drew low draft). They were used in river warfare during The Civil War. The guns were in the 12 and 24 pound versions and featured a special all wrought iron gun carriage. They were very effective. At their farthest range, The Boat Howitzer had an effective range of 1,270 yards. With Dahlgren's Naval pieces, they ranged from 24 to 32 pound varieties and were used for most Naval ships of The Line. The larger guns (60 to 110 pounders), were used for Coastal defense and siege pieces. Some featured ranges of 3,000 yards. On par with the British Armstrong Gun, The Dalhgren was considered one of the finest Naval and Coastal defense weapons of the 19th Century.