This is a rather nice steam roller made by the Italian company G.I.S.E.A (Giocattoli Italiani Scientifici e Artistici).
The boiler is 42mm diameter x 125mm long. The burner, unusually, sits under the front half of the boiler. The dummy firebox at the rear is too small. Fittings consist of a safety valve and steam pipe only. There is no water level indication.
Steam is fed directly, through a very short pipe, to the back of the port face of the oscillating cylinder. The cylinder (a Mamod replacement) is a single acting type, 8mm bore x 18mm stroke. The piston rod is connected to a disk crank on the crankshaft, at the other end of which is a 50mm diameter brass flywheel. The crankshaft is geared to an intermediate shaft with a speed reduction ratio of approx 4:1. The intermediate shaft drives one of the rear rolls via a pair of pulleys with a ratio of approx 5:1, giving a total speed reduction of approx 20:1. The larger pulley is part of the pressed aluminium rear roll. Exhaust steam is fed to the base of the chimney.
As acquired, the original burner is missing but it has a home made one. I currently run it on Esbit tablets. The original cylinder and piston are missing. A previous owner has fitted a replacement, which appears to be a modern Mamod one. The canopy and support pillars are also new replacements; apparently scratch made.