This is a very rare "experimental" 1883 Diehl lamp invented by Philip Diehl of Elizabethport, New Jersey. Only two Diehl lamps are known to still exist in the world. The only other known Diehl lamp is owned by Dr. Hicks and on display at the "Mount Vernon Museum of Incandescent Lighting" in Baltimore, Maryland. The carbon filament of this Diehl lamp is intact and held by platinum lead ends flattened and folded over to form a clamp to secure the filament in place. Each platinum lead-in is attached to a separate glass stem tip. The most unique feature of this type of lamp is that the copper wires are the 2 end leads of an enclosed coil of copper wire wound around an inner glass tube and surrounded by an outer glass tube and, thereby, is completely contained inside the glass envelope. Each of the 3 layers of copper coil are separated by sheet mica. No wire leads enter or exit the glass envelope. All of this arrangement forms a unique incandescent lamp which is stimulated for illumination through this copper coil "antenna" by an external inducing coil. The Diehl lamp works on the electric induction principle often associated with the work and inventions of Nikola Tesla. "This Diehl lamp" is the only one known to have its evacuation stem open. The open tip was used to evacuate air or to admit different gases during experiments to determine the effectiveness of the concept. The hand written paper label marked "3 A" indicates this lamp's experiment number.