it, which will depresse the water, which when it commeth equall to the degrees, paste the same degree on the place of the water in the other glasse with the vent, and it is done. [Illustration] _How to make the treble perpendicular glasse._ After the same manner is the treble glasse made: but whereas in the double glasse there was but one glasse that had a vent at the top, there is two in this, both whose shanks must contain the iust quantity of water that the glasse without the vent will containe. If you do well obserue the form of the subsequent figure, you cannot goe amisse. [Illustration] _How to make the moveable perpendicular glasse._ First prepare the glasse A, B, fill it almost top-full of water, provide also the glasse K, L, having a loop at the top of it: divide it into so many equall parts as you would haue degrees, and on the mouth thereof fasten a thin board, that will easily slip in and out of the bottom glasse, make then a waight of lead or brasse somewhat heavier than both the glasse and board fastned thereto; and then tie a little rope to the loop of the glasse A, B, and the waight at the other end thereof. Rarify the ayre contained in the glasse L, and reverse it into the glasse A, B, filled with water, and hang the plummet over two little pulleys fastned in a frame made for the purpose, and as the glasse K, L, cooleth, the water will ascend the same, and so by the change of the outward both the glasse and water will move accordingly. [Illustration] _Of the use of all the severall sorts of Weather-glasses._ Albeit the formes of Weather-glasses are divers, according to the fancy of the Artist, yet the use of all is one and the same: to wit, to demonstrate the state, and temper of the season, whether hot or cold; as also to foreshew the change and alteration thereof. 1 Note therefore, that the nature and property of the water in all the glasses that have no vent holes at the top, is, to ascend with cold, and descend with heat. But in them that have vents, it descendeth as much as it ascendeth in these. 2 The sudden falling of the water is an evident token of rayne. 3 The continuance of the water at any one degree, is a certaine token that the weather will continue at that stay it is then at, whether it be fayre, or foule, frost or snow. But when the water either riseth or falleth, the weather will then presently change. 4 The uncertaine motion of the water is a signe of fickle weather. The single perpendicular with a vent, moveth upwards with cold, and downwards with heat, and is quite contrary in quality to the former, only that it moveth uncertainly in fickle and uncertaine weather, and keepeth a constant place in stayed weather.