Planck's law In 1880, André-Prosper-Paul Crova published a diagram of the three-dimensional appearance of the graph of the strength of thermal radiation as a function of wavelength and temperature. He determined the spectral variable by use of prisms. He analyzed the surface through what he called "isothermal" curves, sections for a single temperature, with a spectral variable on the abscissa and a power variable on the ordinate. He put smooth curves through his experimental data points. They had one peak at a spectral value characteristic for the temperature, and fell either side of it towards the horizontal axis. Such spectral sections are
What is a Masterpiece? What is a Masterpiece? What is a Masterpiece? is a 1979 non-fiction book by British historian Kenneth Clark. It is a transcribed version of the Walter Neurath memorial lectures given by Clark. The work, initially released on 1 January 1979, received a Thames & Hudson republication on 1 May 1992. Kenneth Clark had already achieved fame with a series of popular books while also serving as, from 1969 on, the writer, producer and presenter of the BBC programme, "Civilisation", a pioneering television documentary series. The prestigious series earned a Peabody Award as well as general commercial success. In the work,