**(Evangelista Torricelli, 1644)**

If one rotates a hyperbola around an asymptote, as around an axis, one generates a solid infinite in length in the direction of the axis, which we call an acute hyperbolic solid…It may seem incredible that although this solid has an infinite length, nevertheless none of the cylindrical surfaces we considered has an infinite length but all of them are finite, as will be clear to everyone who is even modestly familiar with the doctrine of Conics.