Thomas A. Edison Papers. Electric Generator. In the fall of 1878, after experiments indicated that existing arc light generators were inefficient for incandescent lighting Edison and his chief assistants, Charles Batchelor and Francis Upton, investigated generator design and the principles of electromagnetism.
Size. The standard width of a residential range is 30 inches, but higher-end ranges can extend to 36 inches and beyond. The oven compartment on a typical range is 5 cubic feet, compared to just over 3 cubic feet in a typical wall oven.
Typically, half-sheets measure 13 by 18 inches -- the perfect size, since most ovens have an interior rack that measures 22 inches wide (for optimal results, several inches are needed around the baking sheet for air to circulate). Similar baking sheets are available in smaller sizes.