Siphon barometer placed in a wooden box with glass front window. The inside is lined with arabesqued paper. The barometric scales are printed on a sheet of paper. They are surmounted by the Medici coat of arms, below which is the inscription "Magnum Barometrum" and some instructions for using the instrument. There is also a thermometer, whose bulb is broken. The instrument is fitted with a recording pointer running on a vertical metal wire. The similarity with the two barometers inv. 3627 and inv. 1141 suggest an attribution to Giovanni Domenico Tamburini, about whom we have no information.