Vintage machine tool catalogs and brochures offer us an excellent view of production history in the US. As demand and production increased these machine tools evolved to do more specific jobs in a quicker and more efficient manner. Its amazing to see photos of some of these tools lined up row after row in a factory. I love the huge presses that were in use as well as lathes and grinders. I always have a nice stock of these brochures and catalogs from the 1930's to the 1960's in stock in my ebay store: Reed's Olio of Fun Stuff.