There is a fascination about the simple oscillating steam engine which attracts even the builders of true-scale, exact-to-prototype quadruple expansion marine engines! It may be their sheer simplicity of mechanism, it may be memories of childhood days when Father Christmas put one in the stocking, or it may just be the fun of seeing the machine work. This book describes the making of four such models: Polly - a vertical steam plant. Elizabeth - a horizontal steam power plant. Hercules - a working model steam crane. Jenny Wren - a miniature vertical steam engine. The author built all four himself, and the first three were all featured in articles which appeared in Model Engineer magazine and elsewhere. Designs and methods of construction are clearly detailed with instructions that even a beginner will be able to follow.