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,
Dutch sloop Havik (1784) Dutch sloop Havik (1784) The Dutch sloop "Havik" was launched in 1784. The British captured her in 1796 at the capitulation of Saldanha Bay. She then served briefly in the Royal Navy as HMS "Havick" (or "Havik", or "Havock") before she wrecked in late 1800. "Havik" was a ship sloop with a quarter deck, built at Amsterdam in 1784 for the Admiralty of Amsterdam under the 8th Charter. At Saldanha Bay a squadron of the Batavian Navy, under the command of Rear-Admiral Engelbertus Lucas, surrendered without a fight to a Royal Navy squadron under the command of Vice-Admiral George Elphinstone