Accessories for Simmance-Abady Flicker photometer by Nalder Brothers & Co., London, c.1910. Accessories for Simmance-Abady Flicker photometer by Nalder Brothers & Co
Simmance-Abady momentary flash lamplighter's torch for incandescent gas street lighting, patented 1899 Simmance-Abady momentary flash lamplighter's torch for incandescent gas street lighting
Copy of "Simmance & Abady's Copyright Tables of Corrections for Harcourt's 10-candle Pentane Lamp", (for use with 1957-114) Copy of "Simmance & Abady's Copyright Tables of Corrections for Harcourt's 10-candle Pentane Lamp"
Simmance-Abady Flicker photometer by Nalder Brothers & Co., London, c.1910. Simmance-Abady Flicker photometer by Nalder Brothers & Co.
