Pope Miniature Sintered Tungsten Filament

Pope was one the earliest Dutch lampmakers, having been set up prior to Philips by the Englishman Francis Robert Pope. He was previously an employee at Joseph Swan's carbon lamp factory, and emigrated to the Netherlands to pursue his ambition of establishing his own factory because at that time that country had no patent laws. Lampmaking was established at Venlo in 1889 and Pope grew impressively by undercutting the skilled labour costs of other lamp factories. He trained girls as young as 12 to make lamps, and due to their low wages the company became more prosperous its competitors. These lamps were mainly exported, under the Pope and Condor brands.

In 1908 the company introduced its first tungsten filament lamps, and the name was changed to N.V. Pope's Metaaldraadlampenfabrieken. A year later in 1909 a British subsidiary was founded, which made tungsten lamps at Willesden under the Elasta brand. However Pope lost its lead as the Dutch industry began to consolidate. After Philips absorbed the Constantia Lamp Works in 1904, the much smaller Pope struggled to compete with the larger combines. Pope succumbed to Philips in 1920, and lampmaking continued until 1932 before relocating into Philips' works. In 1934 the British Pope factory was taken over by GEC.

It is not certain if this sintered tungsten lamp is of British or Dutch origin, however the style of cap has a distinctly British appearance. The bulb contains two short hairpin filaments of tungsten wire electrically connected in parallel, which have been arc-welded to the leading-in wires. The stem contains platinum sealing wires. It is a fairly standard low voltage lamp, presumably made for battery operation.
Manufacturer: Pope
Lamp Power: 9.3 Watts
Lamp Voltage: 4 Volts
Lamp Current: 2.33 Amperes
Cap Type: B15d Brass + vitrite
Bulb Type: G-35 G-11 in eighths/inch
Bulb Finish: Clear Soda-lime glass
Filament Type: 2S-2 Double Hairpin
Atmosphere: Vacuum
Luminous Flux:
Luminous Efficacy:
Luminous Intensity: 8 Candle Power
Beam Distribution: N/A
Colour Temperature & CRI: CCT: 2700K CRI: Ra 100
Chromaticity Co-ordinates: CCx: 0.460 CCy: 0.411
Rated Lifetime: Approx. 1000h
Burning Position: Universal
Overall Length: 57 mm 21/4 inches
Light Centre Length: 33 mm 15/16 inches
Factory: Willesden, UK or Venlo, The Netherlands
Date of Manufacture: Approx. 1908-1912
Original Value: Unknown
References: 1) Photo-electric measurement
2) The History of N.V. Philips Gloeilampenfabrieken, Volume 1, A.Heerding, publ. Cambridge University Press, 1985.
3) The History of N.V. Philips Gloeilampenfabrieken, Volume 2, A.Heerding, publ. Cambridge University Press, 1988.