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.
A good way to clean silverware of all coloring by eggs or other substances is to place the silver articles in a kettle of boiling water containing a few pieces of zinc, An electrolytic action is produced by the zinc, water and silver which decomposes the sulphides on the silver and leaves it well cleaned. No silver is taken away by this method. - Contributed by Loren Ward, Des Moines, Iowa.