Many of Ritter's researches were guided by a search for polarities in the several "forces" of nature, and for the relation between those "forces" – two of the assumptions of "Naturphilosophie". In 1801, after hearing about the discovery of "heat rays" (infrared radiation) by William Herschel (in 1800), Ritter looked for an opposite (cooling) radiation at the other end of the visible spectrum. He did not find exactly what he expected to find, but after a series of attempts he noticed that silver chloride was transformed faster from white to black when it was placed at the dark region of the Sun's spectrum, close to its violet end. The "chemical rays" found by him were afterwards called ultraviolet radiation. Some of Ritter's researches were acknowledged as important scientific contributions, but he also claimed the discovery of many phenomena that were not confirmed by other researchers. For instance: he reported that the Earth had electric poles that could be detected by the motion of a bimetallic needle; and he claimed that he could produce the electrolysis of water using a series of magnets, instead of Volta's piles. Ritter had no regular income and never became a university professor, although in 1804 he was elected a member of the Bavarian Academy of Science (in Munich). He married in 1804 and had four children, but he was unable to provide the needs of his family. Plagued by financial difficulties and suffering from weak health (perhaps aggravated by his electrical self-experimentation), he died young in 1810, as a poor man.