Editing Alexander Graham Bell (section)

===Hydrofoils===
{{Main|HD-4}}
[[File:Bell HD-4.jpg|thumb|Bell's [[HD-4]] on a test run ca. 1919]]

The March 1906 ''[[Scientific American]]'' article by American pioneer William E. Meacham explained the basic principle of [[hydrofoil]]s and [[Hydroplane (boat)|hydroplanes]]. Bell considered the invention of the hydroplane as a very significant achievement. Based on information gained from that article, he began to sketch concepts of what is now called a hydrofoil boat. Bell and assistant [[Frederick W. Baldwin|Frederick W. "Casey" Baldwin]] began hydrofoil experimentation in the summer of 1908 as a possible aid to airplane takeoff from water. Baldwin studied the work of the Italian inventor [[Enrico Forlanini]] and began testing models. This led him and Bell to the development of practical hydrofoil watercraft.

During his world tour of 1910–11, Bell and Baldwin met with Forlanini in France. They had rides in the Forlanini hydrofoil boat over [[Lake Maggiore]]. Baldwin described it as being as smooth as flying. On returning to Baddeck, a number of initial concepts were built as experimental models, including the ''Dhonnas Beag'' (Scottish Gaelic for 'little devil'), the first self-propelled Bell-Baldwin hydrofoil.{{sfn|Boileau|2004|p=18}} The experimental boats were essentially proof-of-concept prototypes that culminated in the more substantial [[HD-4]], powered by [[Renault]] engines. A top speed of {{convert|54|mph|km/h}} was achieved, with the hydrofoil exhibiting rapid acceleration, good stability, and steering, along with the ability to take waves without difficulty.{{sfn|Boileau|2004|pp=28–30}}

In 1913, Dr. Bell hired Walter Pinaud, a Sydney yacht designer and builder as well as the proprietor of Pinaud's Yacht Yard in [[Westmount, Nova Scotia]], to work on the pontoons of the HD-4. Pinaud soon took over the boatyard at Bell Laboratories on Beinn Bhreagh, Bell's estate near [[Baddeck, Nova Scotia]]. Pinaud's experience in boatbuilding enabled him to make useful design changes to the HD-4. After the First World War, work began again on the HD-4. Bell's report to the [[United States Navy|U.S. Navy]] permitted him to obtain two {{convert|350|hp|kW|abbr=off|adj=on}} engines in July 1919. On September 9, 1919, the HD-4 set a world marine speed record of {{convert|70.86|mph|km/h|abbr=off}},{{sfn|Boileau|2004|p=30}} a record which stood for ten years.