Optician more important and dignified. Far-sighted or aging colonial Americans imported spectacles from Europe. Spectacles were primarily for the affluent and literate colonists, who required a valuable and precious appliance. Benjamin Franklin in the 1780s developed the bifocal. Bifocal lenses advanced little in the first half of the 19th century. The terms bifocal and trifocal were introduced in London by John Isaac Hawkins, whose trifocals were patented in 1827. In 1884 B. M. Hanna was granted patents on two forms of bifocals which become commercially standardized as the "cemented" and "perfection" bifocals. Both had the serious faults of ugly appearance, fragility,
HMS Crescent (1784) she remained in home waters and passed to Captain John Temple who was in command when "Crescent" was wrecked off the coast of Jutland on 6 December. More than 200 people died as a result, including Temple himself. HMS Crescent (1784) HMS "Crescent" was a 36-gun "Flora"-Class frigate of the British Royal Navy. Launched in 1784, she spent the first years of her service on blockade duty in the English Channel where she single-handedly captured the French frigate, "La Reunion". In 1795, "Crescent" was part of a squadron commanded by George Elphinstone, that forced the surrender of a Batavian Navy