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 Child Is This? years later in 1871, when it featured in "Christmas Carols Old and New", a "prestigious" and "influential" collection of carols that was published in the United Kingdom. The hymnal was edited by Henry Ramsden Bramley and John Stainer; even though it is not known with certainty who paired the three stanzas from "The Manger Throne" with the music from "Greensleeves", the third edition of "The Christmas Encyclopedia" by William D. Crump and "Stories of the Great Christmas Carols" both suggest that Stainer – who was also responsible for "harmoniz[ing] the musical setting" – may have done so. What Child Is