Johann Wilhelm Ritter (1776 -1810)

Johann Ritter (Figure 6) was a German physicist born on December the 16th, 1776 in Samitz bel Haynau Silesia, now Poland. He devoted his efforts to studying electricity and electrochemistry. However his main discovery was the ultraviolet region of the spectrum. He believed it 'broadened man's view beyond the narrow region of visible light to encompass the entire electromagnetic spectrum from the shortest gamma rays to the longest radio waves'. Ritter discovered that silver chloride decomposed in the presence of light, and that it decomposed at an even faster rate when exposed to invisible light. This proved that there was unknown radiation beyond the violet end of the spectrum - thenceforward to be called 'ultraviolet'. It wasn't until the twentieth century, however, that any photographic records in either of these spectra were made.

Figure 6 (left). Johann Wilhelm Ritter.

During his time, Ritter was interested in experiments of electrical excitation of muscles and sensory organs. Most of the success from these studies was because he used his own body in the experiments even when using high voltages. It is said that this type of work may have played a high personal toll on Ritter's body. He became very ill, and died on January the 23rd, 1810 at the early age of only 33.

References:

• Ritter, J., 1801, Intelligenzblatt der Erlanger Litteraturzeitung, No 16 Feb 22.

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