Carcel lamp

The Carcel lamp was an efficient lighting device used in the nineteenth century for domestic purposes and in France as the standard measure for illumination.

[3] The advantages Carcel claimed for his lamp in his 1800 patent in Paris were that the movement operated unattended, the oil could be used to the last drop, the lamp would stay lit for sixteen hours continuously without refilling, and it provided illumination for several persons at the same time with a single burner.

Their unpopularity was partially due to the necessity of having to return them to the (mostly European) manufacturers for repair.

[4] In 1829 the simpler Moderator lamp was invented, which dispensed with clockwork and used only a weighted piston to move the oil, and this eventually superseded them.

The French physical standard Carcel lamp consisted of a cylindrical Argand burner, and gave the standard brightness when 42 grams of colza oil were consumed per hour.