Two New Sciences

others, which are in the mouths of the ill-informed, I believe were introduced by them to show they know how to say something about that of which they are incapable.

Salviati. Your Lordship perhaps means to speak of the last statement he uttered, while we were trying to understand the reason why they made such much greater preparation of supports, rigging, and other reinforcements and fortifications around that large Galeass a large Venetian galley that was to be launched, than is done around smaller vessels, to which he replied that this is done to avoid the danger of breaking its back, crushed by the very heavy weight of its vast bulk, an inconvenience to which smaller ships are not subject?

Sagredo. I mean that, and above all the last conclusion he added, which I have always esteemed a vain concept of the common people: that is, that in these and other similar machines one must not argue from the small to the large, because many inventions of machines succeed on a small scale, but do not subsist in large ones. But since all the reasons of mechanics have their foundations in Geometry, in which I do not see that greatness and smallness make circles, triangles, cylinders, cones, and any other solid figures subject to different properties, when the large machine is built in all its members according to the proportions of the smaller one, which is valid and resistant to the work for which it is destined, I do not see why it should not also be exempt from the setbacks that might happen to it, which are sinister and destructive.

Salviati. The saying of the vulgar is absolutely vain, and so vain that its opposite could be stated with equal truth, saying that many machines could be made more perfect on a large scale than on a small one, as for example a clock, which shows and strikes the hours, will be made more accurate at one size than at another, smaller one. Others more intelligent use that same saying with better foundation, who attribute the failure of such large machines, not conforming to what is gathered from pure and abstract demonstrations...