Alexander Graham Bell is best known for inventing the telephone, but he was a man of many interests. Another product for which he received patents was:
A) A cement-burning kiln B) A hydrofoil boat ü C) A “magic lantern” projector D) A vacuum cleaner
In later life, Bell lived in Nova Scotia, Canada, where he worked for years with Casey Baldwin to develop a practical hydrofoil watercraft. A hydrofoil has a wing-like structure on its hull that raises the boat out of the water when it is moving; the consequent reduction in drag allows the boat to achieve much greater speeds. In 1919, Bell’s hydrofoil, the HD-4, set a world marine speed record of over 70 miles (110 km) per hour that stood for ten years. The cement-burning kiln was patented by Thomas Edison, the vacuum cleaner by I.W. McGaffers, and the “magic lantern” projector by Henry R. Heyl.
