This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
In an emergency, and to substitute something for a broken glass rubbing plate on an ordinary washing board, I fitted a series of 3/8-in. dowels horizontally across the board, closely together. This proved to be better than glass or zinc, as fabrics adhered to the wood dowels and caused them to revolve, making a more desirable rubbing surface and accomplishing the work of loosening the dirt in the fabric with far less effort than that necessary on the metal or glass board. - Contributed by H. M. Spamer, Vineland, N. J.