What are isothermal lines?

Some articles on isothermal lines:

Humboldtian Science - Humboldt’s Equilibrium
... to graphically represent this continuity Humboldt developed isothermal lines, which denoted isotherms ... These isothermal lines functioned in the general balancing of forces in that isothermal lines preserved local peculiarities within a general regularity ...

Famous quotes containing the word lines:

    Every living language, like the perspiring bodies of living creatures, is in perpetual motion and alteration; some words go off, and become obsolete; others are taken in, and by degrees grow into common use; or the same word is inverted to a new sense or notion, which in tract of time makes an observable change in the air and features of a language, as age makes in the lines and mien of a face.
    Richard Bentley (1662–1742)