Blackball. England. She was 290 feet Ions, and 

 each hull had a beam of 17 feet. The paddle wheel 

 was placed between the hulls and, ready for sea, she 

 drew 6V, feet. She ran the 22 miles between Dover 

 and Calais in 1 hour and 50 minutes, a speed much 

 slower than that of the paddle-wheel, cross-channel 

 steamers having one hull. Another double-hull 

 steamer was built for this service by Hawthorn, 

 Leslie and Company. Newcastle-on-Tyne, Scotland, 

 in 1877. First named Express, she was renamed 

 -Douvres when she went into service in May 

 1878. Her length was 302 feet, her extreme beam 

 62 feet, and each hull had a beam of 18 feet, 3 inches. 

 She drew 6-foot 7 1 ; inches ready for sea and the paddle 

 wheel was between the hulls. On her trials she made 

 14 knots and burned coal excessively. Sold to France 

 in 1880, she was taken out of service in 1889. Though 

 popular, she was not faster than the single-hull 

 steamers in this service and had been a comparatively 

 expensive vessel to build and operate. 



The many attempts to produce a very last double- 

 hull steamer and large sailing vessels have led to 



disappointment for their designers and sponsors. In 

 the history of naval architecture, since Petty's time, 

 there have been a number of periods when the new- 

 old idea of the double hull has become popular. 

 Craft of this type have been commonly well publi- 

 cized but, on the whole, their basic designs have 

 followed the same principles over and over again and 

 have not produced the sought-for increase in speed 

 and handiness. 



In very recent years there has been a revival in 

 interest in sailing double-hull boats that is enthu- 

 siastic as to very small craft and somewhat re- 

 strained as to large boats. A few projects are under 

 development for double-hull craft, power and sail, 

 of over 90-foot length, including an oceanographic 

 research vessel. In general, however, the performance 

 of double-hull boats has shown that Chapman's 

 estimate of the type was reasonably correct and that 

 there are limitations, particularly in maneuverability 

 in the double-hull craft that could have been found 

 by reference to the history of past experiments with 

 the type. 



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BULLETIN 210: CONTRIBUTIONS FROM II II. Ml'SF.UM OF HISTORY AND TECHNOLOGY 



