A 17th century Hebrew text by physician and rabbi Joseph Solomon Delmedigo describes a liquid-in-glass thermometer. A philosophy professor from the University of Arkansas (Jacob Adler) discovered that this description of a liquid-in-glass thermometer predates the earliest known by at least 20 years. The thermometer is essentially the same as those used today, except that it was filled with brandy rather than mercury. This description is from Ma’yan Ganim (A Fountain of Gardens) which is part of Delmedigo's book "Elim", published in 1629 and written by the aforementioned physician and rabbi Joseph Solomon Delmedigo.

Delmedigo does not claim to have invented the device says Adler. In fact, he appears to have been more of a journalist than a scientist. In an age when scientific journals were unknown, he spread news of discoveries across Europe through his many letters to such eminent contemporaries as the astronomer Johannes Kepler. Adler suspects that Galileo (or perhaps a physician named Santorio Santorio), invented the device. Both taught at the University of Padua where Delmedigo studied medicine.

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