By: Petr Vanýsek

The discovery of an electric arc can be tied to the use of an electrochemical energy source. Sir Humphry Davy described in 1800 an electric discharge using electrochemical cells¹ that produced what we would call a spark, rather than an arc. However, in 1808, using an electrochemical battery containing 2000 plates of copper and zinc, he demonstrated an electric arc 8cm long. Davy is also credited with naming the phenomenon an arc (Fig. 1). An electric arc was also discovered independently in 1802 by Russian physicist Vasily Petrov, who also proposed various possible applications including arc welding. There was a long gap between the discovery of the electric arc and putting it to use.

Electrochemical cells were not a practical source to supply a sustained high current for an electric arc. A useful application of this low voltage and high current arc discharge became possible only once mechanical generators were constructed. Charles Francis Brush developed a dynamo, an electric generator, in 1878, that was able to supply electricity for his design of arc lights. Those were deployed first in Philadelphia and by 1881 a number of cities had electric arc public lights. Once that happened, the application and new discoveries for the use of the electric arc followed. Electric arc for illumination was certainly in the forefront. First, electric light extended greatly the human activities into the night and second, public street electric lights, attracting masses of spectators, were the source of admiration, inspiration, and no doubt, more invention.

(more…)

Edward Goodrich Acheson (1856-1931), one of the charter members of ECS, is best known for having invented and commercialized carborundum, an artificial graphite.

Biography

Acheson was born in southwestern Pennsylvania and raised its coal fields. At the age of 16, after his father died, he left school to help support his family. Nevertheless, Acheson devoted his nights to the scientific endeavors, especially electrical experiments.

In 1880, Acheson attempted to sell a battery of his own invention to Thomas Edison, who ended up hiring him to assist with his research. He experimented with creating a conducting carbon that Edison could use in his electric light bulbs.

After working for Edison for four years, Acheson left his employ to become an independent inventor. In 1891, Acheson acquired access to an electric
generating plant and attempted to use electric heat to impregnate clay with carbon. What resulted from this experiment was his discovery of a crystalline substance that had value as an abrasive, which Acheson named “carborundum” (also known as silicon carbide).

In 1894, he established the Carborundum Company in Monongahela City, Pennsylvania, which created grinding wheels, whet stones, knife sharpeners, and powdered abrasives. Later, Acheson used his electric furnace to produce artificial graphite, which  he commercialized, discovering that various organic substances allowed colloidal suspension of particles of graphite mixed in oil or water.

Acheson received 70 patents related to abrasives, graphite products, reduction of oxides, and refractories. ECS awarded him the first Acheson Award, named in his honor, in 1931.

(more…)