Set of twelve thermometers divided into fifty degrees, one of the many thermometric scales adopted by the Accademia del Cimento. The thermometers are fixed to a wooden table and end in spherical bulbs. The degrees are represented by small dots of black enamel for single degrees and white enamel for ten degrees. The thermometric liquid consists of acquarzente. Invented by Grand Duke Ferdinand II de' Medici, fifty-degree thermometers were generally used to measure the variations in heat and cold of the air, both outdoors and indoors. The academicians made extensive use of the instrument, chiefly for meteorological observations: the advantage of these thermometers was that their readings were comparable with one another, even though they were not the most sensitive.