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Excerpted from The History of Oilfield Diving: An Industrial Adventure
by Christopher Swann (Oceanaut Press)
by Christopher Swann (Oceanaut Press)
On June 26 1840 Augustus Siebe, a Prussian who had emigrated to England in 1816, delivered his "close" or "tight" dress diving apparatus to Colonel Charles Pasley, Director of the Royal Engineers Establishment at Chatham. Pasley was then at Portsmouth, engaged in the second year of a four-year operation to clear the wreck of the Royal George—a warship of 100 guns which had capsized in 1782 with a loss of some 900 lives—from Spithead anchorage. Initially, he provided his divers with two types of equipment. The first was the "open" dress design of the brothers Charles and John Deane, so called because water was free to enter the bottom of the helmet by way of the short jacket to which it attached. The second was John Bethell's "close" dress which, by definition, like the Siebe apparatus, enclosed the diver entirely, with only his hands, sealed at the wrists, exposed to the water.
Siebe was a remarkable craftsman and inventor, with numerous engineering developments to his credit. It was not until 1830, however, that he began manufacturing diving equipment, when the Deane brothers commissioned him to build their open copper helmet. This was based on a helmet and jacket, originally designed for entering smoke-filled buildings and subsequently adapted to diving, that Charles Deane had patented in 1823. By May 1837, the year the patent on the Deane apparatus lapsed, Siebe had made and sold 20 sets under license.
By all accounts, it was regarded as practical and efficient equipment. Nonetheless, despite impressive work by the Deanes and others on numerous wrecks, including the Royal George (for which Charles Deane held the salvage rights until Pasley ousted him in 1839), the open dress had the serious disadvantage that the diver could not lean far forward without flooding the helmet. If he tripped or fell into a hole, he could easily drown. Hence the attraction of the close dress. Being closed to the water, it eliminated the danger of drowning and allowed the diver to work in almost any position. Unfortunately the Bethell dress, the first of the type to appear in Britain (an American, Leonard Norcross, patented a close dress in 1834, the year before Bethell), was still not the answer, at least not to Pasley's divers. This is because they found the method of sealing the two-part suit at the waist intolerably time consuming. They soon cut it up and turned it into an open dress.
In March 1839, five months before Pasley started work on the Royal George, George Edwards, the harbor master of the Port of Lowestoft, staged a public demonstration of his diving apparatus, the fourth close dress since that of Norcross. The diver climbed into the suit through the neck, and the one-piece helmet and breastplate, which was contoured to the shoulders, was clamped to the dress using a loose flange arrangement secured by thumbscrew nuts.
Edwards, who had bought an open dress from Siebe in 1837, was not interested in profit; his sole purpose was to make diving safer. Consequently he gave Siebe permission to adopt the design, and in May 1840 the Naval Storekeeper General placed the first order for a Siebe-manufactured close dress.
Although the Siebe apparatus, complete with a spring-loaded exhaust valve, represented a considerable step forward, Pasley's divers complained that it took two minutes to remove the helmet from the dress, whereas they could get out of the Deane helmet in 15 seconds. This objection was duly relayed to Siebe and on August 26 1840 he delivered a new version with an interrupted thread neck ring, which for the first time allowed a helmet to be removed from its breastplate. The ‘diver's attendant’ simply unscrewed the helmet one-eighth of a turn and lifted it off.
Pasley subsequently made two changes to the helmet. He modified the exhaust, eliminating the external siphon pipe which proved superfluous; and in 1842, after two divers suffered a severe squeeze when their hose ruptured, resulting in a rapid loss of pressure, he ordered the fitting of non-return valves. The Standard Diving Apparatus, essentially the Deane design as modified by Edwards, had arrived. Commonly referred to as "standard dress" in British circles and "heavy gear" or "hard hat" in North America, it remains in use little changed to this day.
