BLOCK n.
A grooved pulley or sheave incased in a frame or shell which is provided with a hook, eye, or strap, by which it may be attached to an object. It is used to change the direction of motion, as in raising a heavy object that can not be conveniently reached, and also, when two or more such sheaves are compounded, to chang…
PUPA n.
nd snails having an elongated spiral shell. Coarctate, or Obtected, pupa, a pupa which is incased in the dried-up skin of the larva, as in many Diptera. -- Masked pupa, a pupa whose limbs are bound down and partly concealed by a chitinous covering, as in Lepidoptera.
WATERING n.
rechites. The valves are small, and consolidated with the capacious calcareous tube which incases the entire animal. The tube is closed at the anterior end by a convex disk perforated by numerous pores, or tubules, and resembling the rose of a watering pot. -- Watering trough, a trough from which cattle, horses, and o…