PRINCE was built as a side tank locomotive with a separate tender for carrying coal. A large cast iron weight was soon added to the top of the tanks to give it more adhesion and making it resemble a saddle tank engine, but it was not until the 1890s when it was completely rebuilt with a true saddle tank. How much of the original 1863 loco survived this rebuild is open to conjecture, but whilst the appearance changed a lot, structurally and mechanically it was still the same underneath. It remained in this form, with remarkably few changes through both World Wars, Closure, and early preservation days. (There is good photographic coverage throughout this period). From the 1960s, various alterations were made to remedy perceived defects in the 1860s construction technology, culminating in new redesigned structural frames, enlarged cab, enlarged smokebox (to accommodate a superheater), and widened tender. The present day loco is thus significantly bigger than before, but we should be glad that a mid-nineteenth century loco is still working on its original railway well into the twenty first century.
Slater's model represents the locomotive after its rebuild as a saddle tank in the 1890s up to when it was modernised from the 1960s onward. Alternative parts are included to enable the few changes which were made to be modelled. Although they are superficially similar, PRINCESS, and particularly PALMERSTON, are different enough that it was not possible to enable a single kit to cover all three locomotives.
The kit includes the loco and tender, and is supplied complete with motor, gearbox and correct wheels, and is suitable for 2-rail electric operation or for battery power. The tender and the large saddle tank means that there is plenty of room for batteries, chargers, or any form of electronic remote control, but none of this is included.
Construction follows closely the methods established with ROUGH PUP, i.e. etched brass frames, footplate, cab and tender body, high quality urathane resin castings for the smokebox, saddle tank, firebox etc., and lots of lost wax brass and nickel silver castings. Some fittings, including the chimney are precision turnings, as are the distinctive oval section coupling and connection rods. Altogether, assembly is very straightforward, and should be well within the capabilities of someone with only limited experience of locomotive kit building.