NIR TIME LINE NIR Spectroscopy : Doing

Herschel used thermometers to determine the heating effect of the sun's rays. He observed elevated temperatures " beyond the red. " Birth's classical diffuse reflectance experiment: All bottles contain same size glass particles. Media surrounding particles: (A) air, (B) water and (C) mineral oil. 1666—Newton disperses white light into colors 1668—Mariotte finds heat disappears when glass inserted in beam 1704—Newton publishes Opticks, Spectroscopy Becomes Science Ed Stark founded CNIRS in 1986. Wilhelm Herschel was one of ten children (of which four died at an early age). In 1775, as a member of the marching band of the Hanoverian Guards, he was ordered to England. It was a peaceful time between the Germans and the English under the leadership of Geroge II. Herschel spent most of his time learning English. Music led him to become interested in mathematics and astronomy. Mathematics and love for astronomy turned his attention to building of telescopes when he became acquainted with the Reverend Doctor Nevil Maske-lyne, who held the office of fifth British Astronomer Royal from 1765-1811. His sister, Caroline, joined Herschel in England and became his most loyal fan and supporter, serving as his full-time assistant, taking notes while he observed at and worked on the telescope. During his career Herschel constructed more than 400 telescopes. Customer complaints about " burning pain " when looking into Herschel's telescope caused him to study the heating effects of the sun's rays. He dispersed the suns rays with a glass prism into colors and measured the heat generated by the colors (See page one for a sketch of his experimental setup.). When he serendipitously observed the increase in temperature beyond the red zone, he concluded that some form of invisible light was effecting the increase. Indeed, it must have been near-infrared energy. Herschel wrote three papers on this discovery. lady. They had one son, John, who followed in his father's foot steps, studying astronomy and spectroscopy. In fact, Norman Sheppard 4 says that " the first measurements of NIR absorption bands were made by Sir John Herschel, " William Herschel's son. John experimental apparatus is shown in Fig. 1 on this page. It was a rather ingenious experiment. Like his father, John dispersed the rays of the sun with a prism; heat from the colors heated the alcohol, the rate of evaporation determined by the c o l o r. T h e v a p o …