Theatrum naturae et artis

more useful. That same effect can be shown expeditiously in an inverted glass immersed in water. This compression is also observed in the air gun pneumatic gun, of which I usually show three types; among these, the last is preferred to the former in various ways.

(d) Which we noted above in the experiments of the air pump suction pump concerning the bladder, and now we show in a small globe, either of glass or copper, into which a little water is enclosed; when placed upon coals, it bursts with a great crash. The air gun teaches the same thing, if the air is given a way to escape and eject the ball. There we have observed several times that the air, if released all at once in a single rush, comes out like smoke and thus presents itself clearly to the sight.

(e) Thermometers indicate this, of which various types are presented, namely the Florentine a type of early liquid-in-glass thermometer, consisting of one glass divided into degrees: another with two, in one of which if the liquid ascends, it descends in the other: another, having various coils. Similar to this is the one handed to the sick person's hand to explore the diversities or degrees of heat. Then we show in what manner various types of thermometers can be constructed, by means of certain glasses and tubes already adapted for this present business.