The following data has been compiled and submitted by fellow collector Raymond Weinstein. I would like to thank Ray for providing the information learned through his research at the Smithsonian's Nela Park archive. The lamp stem drawings shown below have been reproduced from a document from the Smithsonian's Nela Park archive which is dated Jan. 31st, 1916. The photographs have been culled from various sources to provide true-to-life examples to aid the researcher.

Please note that this information applies to Edison/GE lamps only.

Bases

1879-1880 Wooden base with terminal contacts 1880 Copper strips 1880 Wooden screw base 1881 Wood and short brass screw base with collar (Wooden Johnson bevel ring) 1881 Plaster and short brass screw base with collar (Johnson bevel ring) 1881-1884 Plaster and short brass screw base with collar & button contact on bottom 1884-1888 Plaster and short brass screw base (no collar) & button contact on bottom 1888-97 (est.) Plaster insulator and cement with long brass screw base (2-3 treads longer) and button contact 1896*-1900 Porcelain and brass modern shape Edison base, plaster cement (other manufacturers at least until 1902) 1900-1901 Porcelain and brass modern shape Edison base, waterproof cement   1901- Modern type Edison base with glass insulator

* Based on dated photos or other documentation in Smithsonian Institution, Nela Park collection. An
Edison bulb dated to 1894 by construction of the stem (single weld in press & non-flared stem) &
presence of a Madake bamboo filament, possessing a T-H base with porcelain insulator and plaster
cement, suggests the use of porcelain as early as 1894.

Filaments

Carbon 1880-1918 1880-1894 Madake Bamboo (Edison used bamboo in some larger bulbs until after 1900) 1893-1905 Extruded (squirted) carbonized cellulose 1905-1918 (General Electric Metalized) metalized carbon filament     Osmium 1898-1906     Tantalum 1906-1913     Tungsten 1907- 1907-1911 sintered tungsten (under Mazda label starting in 1909) (other manufacturers as early as 1904) 1910 (Nov) modern nonsag tungsten

 

Filament attachments

1881 and before Platinum screw clamps 1881-1886 Crimped copper wire with copper-plating (filaments had large ends to dissipate heat) 1886- Carbon paste (others beside Edison, as early as 1882)

 

Lead-in wires

1880-1881 Thick round seal with glass petticoats (x) on full length platinum wires 1881-1886 Long stem with flat seal and full length platinum lead-in wires (copper hook at top for filament attachment) 1886-1890 Long or short stem with flat seal and single weld within press. No copper hooks due to new use of carbon paste clamp 1890-1894 Double weld within press (copper-platinum-copper) to reduce the use of platinum (copper wire emerges from top of press) 1893- Flared stem base introduced (prior to this, the stem met the envelope at the base at a sharp angle)   1894-1912 Single weld within press with platinum wire emerging from top of press 1912 Single weld within press but platinum wire replaced with nickel iron wire with a platinum sleeve 1913- Single weld within press of copper to Dumet wire (nickel-iron core in an oxygen-free-high-conductivity copper sheath)

 

Getters

1908 First invented 1909- Present in stem cavity

 

Labels

1881(?) - 1887(?) The label was rectangular. The first label read: "16c Edison's Patents". On these lamps the voltage was written on the plaster in the base. 1887(?) - 1899(?) Also had rectangular labels and read: "New Type Edison Lamp, 16c Patented Jan.27, 1880, OTHER EDISON PATENTS". Other lamps of 1887(?) to 1899(?) also had rectangular labels that read: "New Type Edison Lamp, 16c Patented Jan. 14, 1881, Dec. 27, 1881, Sept. 19, 1882, OTHER PATENTS". On these lamps the voltage was printed below C.P. from 1898(?) to 1899(?). About 1887 to about 1901 A round label was used and the ratings were given: 16c/104. About 1901 to about 1905 A horizontal ellipse label was used. One might then find: 16c/EDISON/104.

 

Miscellaneous

1909– Mazda trademark