Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 1, 1802).djvu/284

-54J BET into the outer row of hrles, by which means the exterior notch will rest "on the pin, which will be the centre of motion ; and the end of the lever being pressed downwards, the other notch will be raised, at the same time the chain, and consequently the ram. Afterwards, the other iron pin is to be put into the hole in the inner row, above that which was before the centre, of motion, and the end of the lever elevated or pushed up- wards, the latter pin on which the .notch rests tiien becoming the cen- tre of motion. By this alternate motion of the lever, and shifting the pins, the chain is drawn up- wards over the pulley, and conse- quently the whole force of the engine exerted against the tree. There is a small wheel joined to the end of the ram opposite the pulley, in order to lessen the fric- tion of that part of the machine. From this account, the reader will perceive that the machine is a single pulley, compounded with a lever of the first and second order. As the push of the engine is given in an oblique direcTion, it will exert a greater or less force against the horizontal roots of the. tree, in pro- portion to the angle formed by the machine with the plane of the ho- rizon ; and die angle of 45° is the maximum, or that when the ma- chine will exert its greatest force against the horizontal roots of the tree. Bethlehem. See Star of Beth- lehem. BETONY (Wood), or Be tonka oJjicinaUs, L. a low perennial plant, growing wild in woods and thick- ets j its flowers, which appear in July and August, are of a purplish colour, and stand in spikes on the tops of the stalks. — See With. BEZ 520 ; and Cs;rt. Loud. fuse. 3. t. 33. Tanners have employed this plant as a substitute for oak-bark ; and, according to Dambourkey, the leaves and branches of the betonv, when in blossom, may be used for dyeing wool of a permanent dark- brown colour, when previously dressed in a weak solution of bis- muth. The leaves and flowers have a bitterish taste, accompanied with a weak aromatic flavour. They are mild corroborants, and, when in- fused, or gently boiled, the decoc- tion may be drank as tea : a strong tinemre made in rectified spirit, has proved beneficial in laxity and debility, when taken in small, re- peated doses. It is remarkable, that the roots of this plant greatly differ in qua- lity from the other parts : the for- mer are bitter, nauseous, and, like the roots of hellebore, occasion violent diarrhoea, when taken in a small dose. It is farther affirmed, that betony aifefts those who ga- ther any quantity of its leaves and flowers, with a disorder resembling the effeebs of intoxication. Betula. See BiFxCH. BEZOAR, in natural history and medicine, is a calculous con- cretion, found in die stomach of animals of the goat kind. It is a morbid substance, possessing nei- ther taste nor smell, and it cannot be considered in any other light than as a weak absorbent. In a more comprehensive sense, bezoar includes all concrete substances formed in the intestines of ani- mals : hence pearls, and the con- cretions called crab's eyes, belong to the class of" bezoars. Fossil Bezoar, is a kind of stone formed like the animal bezoar of several