It is getting increasingly diffiult to find the well-regarded Clarkson castings and drawings, they have been unavailable commercially for many years - it's a pity, as they had some fine designs in their catalogue.
This is a set of unmachined castings and unused drawings for the pretty North London Railway Class 75 of 1879. There's still one left - amazingly it was still running in 1960 when saved for preservation by the Bluebell Railway.
Most of the larger castings are in cast iron, including horns and cylinders, smaller bits are in gunmetal.