[HEAT sb. 1 c.] That degree of heat or temperature (higher than red heat) at which metals and some other bodies radiate white light; the state of being white-hot.
1710. J. Harris, Lex. Techn., II. White or Flame Heat; is a Degree of Heat given by Smiths to their Iron…: This is a less Heat than a Welding Heat.
1815. J. Smith, Panorama Sci. & Art, II. 357. If a bar of iron or steel, at a white heat, be rubbed with a roll of sulphur, the two bodies combine,… forming sulphuret of iron.
c. 1865. Letheby, in Circ. Sci., I. 89/2. 2000° (or an incipient white-heat).
b. fig. A state of intense or extreme emotion.
1839. Syd. Smith, Ballot, 8. There are politicians always at a white heat.
1870. Lowell, Study Wind., 148. Carlyle is one of the natures, rare in these latter centuries, capable of rising to a white heat.
1883. W. H. Bishop, House Merch. Prince, xix. 292. There was a vixenish quality in her anger when at white heat which a lover of the amiable in woman would not have cared to see.
