terminology is so terrifying that we are thankful the meteorologists had individual names before he got hold of them; otherwise we shudder to think what he might have done in the way of nomenclature! The same ingenious Frenchman invented an instrument for measuring the sensible temperature which he called at first the "calorisoustractometer"; but later he took pity on humanity and changed its name to "deperditometer."
Of the two evils—a clumsy term or none at all—the former is certainly to be preferred. There can be no progress in ideas without a corresponding progress in language. This fact is emphasized by Whewell; and he cites in illustration the cases of Cæsalpinus in botany, and Willughby in ichthyology, each of whom introduced excellent systems of classification which failed to take root or produce any lasting effect among naturalists because they were not accompanied by corresponding nomenclatures. No one recognized this truth more clearly than Linnæus, whose great contributions to botany were surpassed by his contributions to the language of botany. Whewell quotes a maxim from Linnæus's "Botanical Philosophy,"
Nomina si nescis perit et cognitio rerum,
which ought to be taken to heart by the many scientific men of to-day who are conspicuously shirking their obligations to the technical vocabulary.
In the history of meteorology there are innumerable instances of important ideas that led a precarious existence for years, almost ignored by meteorologists at large, because no one had crystallized them by giving them names. Think of the number of conceptions that owe their present definiteness in our minds to the felicitous terminizing of Ralph Abercromby! The seven typical forms of isobars are familiar examples. Another is the generalization "recurrence," under which term Abercromby united the many cases of the supposed tendency of particular types of unseasonable weather to occur from year to year at about the same period—Indian summer, the "Ice Saints," the "Lammas floods," the "January thaw," the "borrowing days," and a number of other similar interruptions in the regular march of the seasons—all of them more or less elusive when submitted to a rigorous analysis, but none the less deeply-rooted conceptions in the popular mind. Individually these supposed occurrences are familiar to all meteorologists, but we should probably sometimes lose sight of their generic similarity had not Abercromby given them a handy generic name.
Probably in no branch of science is the vocabulary more confused than in atmospheric optics; especially in English. This particular subject affords so many examples of the vices of the existing language of meteorology that we may profitably consider it at some length.
