Theatre of Instruments and Machines

Declaration of the 14th figure.

This machine, having arisen from the preceding one, is similar to it in the structure of its base, and it has one single spoked wheel to move the tree, which the smith pushes with his foot. The other parts are individual. In the middle appears a support composed of two timbers, in the middle of which the saws are raised and depressed, constrained in the slit of each timber. At the northern end of these saws is an Alterabus, whose northern extremities are fixed to the two outer parts of the screws, which are so constituted around the inner bipartite part that by the same motion they move toward the middle and are removed from it by another motion; for this motion is excited by the worker pulling toward himself a rope tied to an arm fixed to the axle of the inner part of the screw toward the west, with a counterweight existing on the other part, upon which the whole force of the motion depends.

PROP. XV.

A new kind of small wagon, which by the labor of one man, on a level or inclined place, can carry as much burden as two or three by any other instrument.

Declaration of the 15th figure.

From the figure itself, the proposition can be perceived, for the two largest wheels, when moved, bring great convenience, for their diameter is greater than the diameter of the smaller wheel which is to the east, since their diameter is three times greater than the diameter of the smaller wheel. Here, however, the painter has poorly placed the driver of the wagon with a backward face, since the smaller wheel ought to go first and he himself ought to be toward it with a forward face, unless descending from a hill he has turned himself thus for convenience.

PROP. XVI.

A new method of vehicle, deduced from the preceding wagon, by which, through the labor of one horse, almost as much burden is carried as is usually done by common two-horse teams.

Declaration of the 16th figure.

The proportion of the wheels of this vehicle to one another is the same as in the preceding wagon; for once that is understood, the ratio of this one is clear. There are, however, only three wheels: two larger ones at the rear, and a single, smaller one at the front.

PROP. XVII.

A new kind of royal vehicle, which indeed is a little wider than common ones, but much more convenient, as it is balanced by its own weight even on uneven ground, so that it is carried as lightly as a boat on calm water, nor can its litter be overturned in any way, nor can anyone who is carried be inconvenienced.

Declaration of the 17th figure.

Those who have greeted the physical sciences from the threshold understand that there are almost two means of all things: one equidistant from the extremities, the other which is explored by a balance, whose ratio is observed here, as you will be able to understand from the following. This part, which is depicted separately and occupies the empty space that turns toward the angle of the east and north, presents itself twice in this vehicle of ours, namely in the front part and the rear part of the vehicle, where the bodies of "anguiped" (snake-footed) maidens are seen joined at the foreheads; between these the litter has its place, for these are attached to the hinge of both wheel axles. In the middle of these said parts is a globe, of which only a smaller part is emitted, in whose hole both hinges of the litter are placed; for the litter is balanced by hinges and rests just as the world does on its poles, so that with the wheels running, there will be no inconvenience to the litter, and this is the principal subtlety of this invention. As for those things which pertain to the motion, since the proportion of the wheels is the same as in common ones, they do not appear and still remain hidden from me.

PROP. XVIII.

A recent form of vessel by which liquids can be exported so that even in the highest heat, they cannot be affected by heat in the same way as in common vessels.

Declaration of the 18th figure.

Perhaps in explaining these I shall attain the author's meaning. First, two vessels present themselves to the eyes, one eastern, the other western; those two are perfect and are one and the same, the rest are parts of it. The northern part is joined with the southern part in the perfection of the vessel, for what are seen in the middle are stored inside; for it is a leather sack and a pipe bent into a circle of iron. The material of it is of the sheets which are called "white iron" [tinplate], in the whitening of which mercury is needed, which has the property of cooling. In this into which the liquids are placed, the liquids—covered by the sack and likewise the vessel—cannot be affected by heat.