That Davy later observed the arc can be deduced from the description he gives in the laboratory log of an experiment in 1808; however, it was only in the volume entitled Elements of Chemical Philosophy, published in 1812, that he spoke explicitly of the arc, giving a precise, detailed description and drawing of his device with horizontal carbons. In that experiment Davy used a battery composed of as many as two thousand Volta piles constructed in the laboratories of the Royal Institution thanks to funds made available by enthusiasts and patrons of science.
This helps us to understand why it was necessary to await the invention of high-power sources of electricity, such as the Daniel pile, discovered in 1836, and the dynamo-electric machines perfected in the second half of the 19th century, before the technical applications and later developments and improvements of the arc lamp could become a reality.
In 1849, Jean Bernard Lèon Foucault (1819-1869), invented a clockwork mechanism for the automatic movement of the carbons, which led to a widening of the range of application of the arc lamp and its use in street lighting.