This incident took place in the winter of 1775, at a house situated near Walcot turnpike, to which Herschel had removed in the summer of the previous year.  Here, on a grass plot behind the house, he made active preparations for the erection of a twenty-foot telescope.  So assiduous was his devotion to this work, that while he was engaged in polishing the mirror, his sister was constantly obliged to feed him by putting his victuals into his mouth.  Otherwise he would have reduced himself to a condition of positive emaciation!  Once, when finishing a seven-foot mirror, he did not take his hands from it for sixteen consecutive hours; for in these days machinery had not been devised as a substitute for manual toil.  He was seldom unemployed at meals; but at such times employed himself in contriving or making drawings of whatever occurred to his fertile fancy.  Usually his sister Caroline read to him while he was engaged at the turning-lathe, or polishing mirrors; choosing such books as “Don Quixote,” the “Arabian Nights,” the novels of Sterne and Fielding; and tea and supper were served without any interruption to the task in which Herschel was absorbed.

In Miss Herschel’s charming letters we find a vivid sketch of the family avocations at this period:—–­

“My brother applied himself to perfect his mirrors, erecting in his garden a stand for his twenty-foot telescope:  many trials were necessary before the required motions for such an unwieldy machine could be contrived.  Many attempts were made by way of experiment against a mirror before an intended thirty-foot telescope could be completed, for which, between whiles (not interrupting the observations with seven, ten, and twenty-foot, and writing papers for both the Royal and Bath Philosophical Societies), gauges, shapes, weights, &c, of the mirror were calculated, and trials of the composition of the metal were made.  In short, I saw nothing else and heard nothing else talked of but about these things when my brothers were together.  Alex was always very alert, assisting when anything new was going forward; but he wanted perseverance, and never liked to confine himself at home for many hours together.  And so it happened that my brother William was obliged to make trial of my abilities in copying for him catalogues, tables, &c, and sometimes whole papers which were lent [to] him for his perusal.  Among them was one by Mr. Michel, and a catalogue of Christian Mayer in Latin, which kept me employed when my brother was at the telescope at night.  When I found that a hand was sometimes wanted when any particular measures were to be made with the lamp micrometer, or a fire to be kept up, or a dish of coffee necessary during a night’s long watching, I undertook with pleasure what others might have thought a hardship.”

The astronomer-musician’s patient survey of the heavens was rewarded, on the 13th of March 1781, by the discovery of a new planet, situated on the