Bronze Age Gold from Wales

White leaflet with black print. Full Title - Special Engineering Publications, Models of Simple Steam Engines. Leaflet consists of descriptions of models, drawn diagrams of a complete single-cylinder steam engine, Willans' Central Valve Compound Engine and a Slide Valve together with Descriptive Geometry Models. Pencil handwritten ammendments are throughout leaflet changing the cover date from Jan, 1915 to 1919 and altering all the prices.