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 prove that the instrument was of a higher type than some thermoscopes of even a later date.

Inverted air thermometers of this construction were, of course, subject to changes in atmospheric pressure, and were properly speaking "baro-thermoscopes," and no two of them were comparable. Sealed thermometers depending upon the expansion of liquids and independent of air pressure, were not made until fifty years later, and instruments with fixed points capable of accurate comparison were not devised until a century had elapsed.

The savants of Italy contemporary with Galileo naturally became acquainted with the great discoveries and inventions associated with his name, and the telescope from its marvelous revelations of celestial phenomena contributed the most to magnify his reputation; the great importance of the thermometer, on the other hand, was appreciated by comparatively few.

One of the colleagues of Galileo, Sanctorius Sanctorius Justipolitanus, who held the chair of the Theory of Medicine at the University of Padua from 1611 to 1624, applied the new instrument to physiological researches and described the results in several of his