Darby

Darby, borough (1990 pop. 11,140), Delaware co., SE Pa., a suburb adjacent to Philadelphia; settled by Quakers 1682, inc. 1853. Although residential, it has some manufactures. One of the oldest settlements in the state, it retains many colonial landmarks. The Darby Library Company was founded in 1743 by Quakers.

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darby [′där·bē]

(engineering)

A flat-surfaced tool for smoothing plaster.

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darby, derby slicker

1. A float tool used in plastering, either wood or metal, about 4 in. (10 cm) wide and about 42 in. (approx. 1 m) long, with two handles; used to float or level the plaster base coat prior to application of the finish coat, or to level the plaster finish coat before floating or troweling.

2. A hand-manipulated straightedge usually 3 to 8 ft (1 to 2.5 m) long, used in the early-stage leveling operations of concrete finishing to supplement floating.

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Darby 

A family of English iron-foundry industrialists.

Abraham Darby. Born 1677 in Worcester; died Mar. 8, 1717, in Madely Court. He served an apprenticeship at a Birmingham malt factory and established his own business in 1698. In 1704 he founded a copper-smelting works in Bristol. In 1708 he obtained a patent for casting iron pots and other ironwares in sand molds. The process advanced by Abraham Darby significantly lessened the cost of production of these wares. In 1709, breaking with his business partners in Bristol, he leased an old blast furnace in Coalbrookdale. In 1713 he introduced coal as an additive to charcoal in blast-furnace smelting.

Abraham Darby. Born Mar. 12, 1711; died Mar. 31, 1763. Son of the first Abraham Darby. In 1730 he became head of the iron foundry in Coalbrookdale. Under him the foundry was expanded and the blast-furnace process was significantly improved. In 1735, Darby mastered blast-furnace smelting on the basis of coking coal without added charcoal.

Abraham Darby. Born Apr. 24, 1750; died Mar. 20, 1791. Son of the second Abraham Darby. In 1768 he became head of iron production. He is known as the builder (1776-79) of a bridge over the Severn River in Coalbrookdale made entirely of cast-iron parts (with a span of 31 m and a height above the water of 12 m). In 1787, Darby received a gold medal from the Society of Arts for a model of that bridge.

REFERENCE

Dictionary of National Biography, vol. 5. London, 1950.