Petrov, Vasily (1803). Извѣстіе о Гальвани-Вольтовскихъ Опытахъ [News of Galvanic-Voltaic Experiments] (in Russian). Saint Petersburg, Russia: Printing House of the State Medical College. From pp. 163–164: "Естьли на стеклянную плитку или на скамеечку со стеклянными ножками будуть положены два или три куска древесного угля, … и отъ которого темный покой довольно ясно освѣщенъ быть можетъ." (If on a glass plate or on a bench with glass legs there be placed two or three pieces of charcoal, capable of producing light-bearing phenomena by means of the Galvanic-Voltaic fluid, and if there are then insulated metal conductors (electrodes), in communication with both poles of a huge battery, bring these closer to each other to a distance [i.e., separation] of one to three lines [2.5-7.5 mm]; then there is between them a very bright white light or flame, from which these coals burn quickly or slowly, and by which the darkness may be quite clearly illuminated.)
In 1801 and 1802, Davy observed bright electrical sparks, but not a continuous arc. His battery lacked sufficient voltage and current to sustain an electric arc.
