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The Morse commercial diving helmet was used extensively throughout the world and had many of the features of the United States Navy Mark V diving helmet, including the distinctive “banana” exhaust, however, it was different because it had two rectangular side lights, a screw in front portal, a different shaped breast plate and a spring loaded lock.
Morse Diving was founded in 1837 in Boston as a maker of brass-ware, three years before Augustus Siebe from England manufactured the first closed air diving helmet. During the Civil War Morse Diving built maritime fittings and began experimenting with underwater hard hat designs based on those made by Siebe and Gorman and other pioneering makers. In 1864 Andrew Morse bought out his partner, Mr. Fletcher, and introduced his sons into the business. They began to focus on creating new products for underwater salvage expeditions. As their expertise and experience grew over the years they developed a worldwide reputation as a major supplier of hard hat deep diving apparatus. Morse Diving was the first company to make the United States Navy Mark V helmet with production commencing in 1916. Morse and Schrader were the only companies making dive helmets for the United States Navy and Army during WWII.