HORNBOOK n.
rmer times they learned their letters and rudiments; -- so called because a sheet of horn covered the small, thin board of oak, or the slip of paper, on which the alphabet, digits, and often the Lord's Prayer, were written or printed; a primer. "He teaches boys the hornbook." Shak.
HYGROMETER n.
r, a form of hygrometer consisting of a bent glass tube terminating in two bulbs, the one covered with muslin, the other of black glass, and containing ether and a thermometer. Ether being poured on the muslin, the black ball, cooled by the evaporation of the ether within, is soon covered with dew; at this moment, the…
ICE n.
ler. -- Ice foot, shore ice in Arctic regions; an ice belt. Kane. -- Ice house, a close-covered pit or building for storing ice. -- Ice machine (Physics), a machine for making ice artificially, as by the production of a low temperature through the sudden expansion of a gas or vapor, or the rapid evaporation of a vol…