times obscured by the failure of the discoverer to claim definitely the product of his inspiration owing to the fact that he himself failed to appreciate its high importance and its utility. The task of sketching the origin of the thermometer is fraught with similar difficulties; the actual inventor is known only at second hand, its development from a crude toy to an instrument of precision occupied more than a century, and its early history is encumbered with erroneous statements that have been reiterated with such dogmatism that they have received the false stamp of authority.
One of the most persistent of these errors is the assertion that the thermometer was invented about the year 1608 by a Hollander named Cornelius Drebbel. Wohlwill and Burckhardt have shown how this blunder originated. In 1624 a book was published at Pont-à-Mousson, entitled "La Récréation Mathématicque," over the pen-name A. van Etten, but written by the Jesuit Father Jean Leurechon, in which the author describes and figures a "thermometer, an instrument for measuring degrees of heat and cold that are in the air." The book was popular, passed through many editions and was translated into several lan-
