Terrestrial telescope consisting of four cardboard tubes. The orange leather covering the largest tube bears the signature of the maker, Leonardo Semitecolo, and carries his characteristic tooling. The leather on the other tubes is white. All the tubes have horn rings, one of which has been replaced by a wooden ring. The largest tube houses the biconvex objective, which has an aperture of 11 mm and a focal length of 370 mm. The smallest tube contains the compound eyepiece, consisting of three biconvex lenses. The mounts for the objective and the eyepiece are of horn and brass with sliding brass covers. The instrument's magnification is 9.