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blue, which is readily acted upon by the substances to whichit must have been exposed in those countries, could not resisttheir influence for so many ages, and retain the beautifulcolours which are admired in the paintings of Herculaneum .The discovery of Prussian blue , according to Stahl, wasaccidental; he states that about the commencement of thelast century Diesbach, a chemist of Berlin, wishing to pre-cipitate a decoction of cochineal with an alkali, borrowedsome potash from Dippel, a brother chemist, on which hehad spveral times distilled his animal oil, but as there wassome sulphate of iron in the decoction of cochineal, theliquor instantly exhibited a beautiful blue in the stead of ared precipitate; reflecting on the circumstances which hadtaken place, he discovered the cause of it, and thus foundhimself capable of producing at pleasure the same substance,which afterwards became an object of commerce, and thepreparation of which he kept for a long time secret. Itobtained the name of Prussian blue , from the kingdom inwhich it was discovered. This colour was sold at a greatprice, and consequently became the subject of research withother chemists ; at length Dr. Woodward got some informa-tion of its preparation from Germany , and published anaccount of the process in 1724, in which he was followed byScheele in 1782.

Blue, says Pliny , was the colour in which the Gauls clothedtheir slaves, and for many ages blue coats were worn byservants and apprentices among the Saxons ; from hence wehave blue coat boys, blue schools, &c.

BOAR. The whole boar, and boar’s heads ornamented,were favorite dishes in the Norman sera, and were served upwith considerable ceremony, music, &c.

BOATS for the preservation of Lives. It is a singularcircumstance that no attempt was made to construct a life-