SELF-HARDENING a.
en when heated to above a red heat and cooled in air, usually in a blast of cold air with moderate rapidity, without quenching. Such steels are alloys of iron and carbon with manganese, tungsten and manganese, chromium, molybdenum and manganese, etc. They are chiefly used as high-speed steels. -- Self`-hard"en*ed, a.…
SLACK a.
Not violent, rapid, or pressing; slow; moderate; easy; as, business is slack. "With slack pace." Chaucer. Cslack southwest, at midnight was becalmed. Milton. Slack in stays (Naut.), slow in going about, as a ship. -- Slack water, the time when the tide runs slowly, or the water is at rest; or the interval between the…
SPECTRUM n.
s by a grating. -- Gaseous spectrum, the spectrum of an incandesoent gas or vapor, under moderate, or especially under very low, pressure. It is characterized by bright bands or lines. -- Normal spectrum, a representation of a spectrum arranged upon conventional plan adopted as standard, especially a spectrum in whic…