قراءة كتاب Sir William Herschel: His Life and Works
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Sir William Herschel: His Life and Works
class="smcap">Lichtenberg) says:
"Herr Herschel was good enough to send me, some time since, through Herr Magellan, copies of his Dissertations on Double Stars, on the Parallax of the Fixed Stars, and on a new Micrometer. In the letter which conveyed to him my thanks for his gift, I requested him to note down a few facts in regard to his life, for publication in this magazine, since various accounts, more or less incorrect, had appeared in several journals. In answer, I received a very obliging letter from him and what follows is that portion of it relating to my request, which was sent me with full permission to make it public."
"Datchet, near Windsor,
Nov. 15, 1783.
"I was born in Hanover, November, 1738. My father, who was a [Pg 4] musician, destined me to the same profession, hence I was instructed betimes in his art. That I might acquire a perfect knowledge of the theory as well as of the practice of music, I was set at an early age to study mathematics in all its branches—algebra, conic sections, infinitesimal analysis, and the rest.
"The insatiable desire for knowledge thus awakened resulted next in a course of languages; I learned French, English, and Latin, and steadfastly resolved henceforth to devote myself wholly to those sciences from the pursuit of which I alone looked for all my future happiness and enjoyment. I have never been either necessitated or disposed to alter this resolve. My father, whose means were limited, and who consequently could not be as liberal to his children as he would have desired, was compelled to dispose of them in one way or another at an early age; consequently in my fifteenth year I enlisted in military service, only remaining in the army, however, until I reached my nineteenth year, when I resigned and went over to England.
"My familiarity with the organ, which I had carefully mastered previously, soon procured for me the position of organist in Yorkshire, which I finally exchanged for a similar situation at Bath in 1766, and while here the peculiar circumstances of my post, as agreeable as it was lucrative, made it possible for me to occupy myself once more with my studies, especially with mathematics. When, in the course of time, I took up astronomy, I determined to accept nothing on faith, but to see with my own eyes everything which [Pg 5] others had seen before me. Having already some knowledge of the science of optics, I resolved to manufacture my own telescopes, and after many continuous, determined trials, I finally succeeded in completing a so-called Newtonian instrument, seven feet in length. From this I advanced to one of ten feet, and at last to one of twenty, for I had fully made up my mind to carry on the improvement of my telescopes as far as it could possibly be done. When I had carefully and thoroughly perfected the great instrument in all its parts, I made systematic use of it in my observations of the heavens, first forming a determination never to pass by any, the smallest, portion of them without due investigation. This habit, persisted in, led to the discovery of the new planet (Georgium Sidus). This was by no means the result of chance, but a simple consequence of the position of the planet on that particular evening, since it occupied precisely that spot in the heavens which came in the order of the minute observations that I had previously mapped out for myself. Had I not seen it just when I did, I must inevitably have come upon it soon after, since my telescope was so perfect that I was able to distinguish it from a fixed star in the first minute of observation.
"Now to bring this sketch to a close. As the king had expressed a desire to see my telescope, I took it by his command to Greenwich, where it was compared with the instruments of my excellent friend, Dr. Maskelyne, not only by himself, but by other experts, who [Pg 6] pronounced it as their opinion that my instrument was superior to all the rest. Thereupon the king ordered that the instrument be brought to Windsor, and since it there met with marked approval, his majesty graciously awarded me a yearly pension, that I might be enabled to relinquish my profession of music, and devote my whole time to astronomy and the improvement of the telescope. Gratitude, as well as other considerations specified by me in a paper presented to the Royal Society, of which I am a member, has induced me to call the new planet Georgium Sidus.
"'Georgium Sidus.—jam nunc assuesce vocari.'—(Virgil.)
And I hope it will retain the name."
We know but little of the family of Herschel. The name is undoubtedly Jewish, and is found in Poland, Germany, and England. We learn that the ancestors of the present branch left Moravia about the beginning of the XVIIth century, on account of their change of religion to Protestantism. They became possessors of land in Saxony. Hans Herschel, the great-grandfather of William, was a brewer in Pirna (a small town near Dresden). Of the two sons of Hans, one, Abraham (born in 1651, died 1718), was employed in the royal gardens at Dresden, and seems to have been a man of taste and skill in his calling. Of his eldest son, Eusebius, there appears to be little trace in the records of the family. The second son, Benjamin, died in infancy; the third, Isaac, was born in 1707 (Jan. 14), and was thus an orphan at eleven years of age. Isaac was the father of the great astronomer.
He appears to have early had a passionate fondness for music, and this, added to a distaste for his father's calling, determined his career. He was taught music by an oboe-player in the royal band, and he also learned the violin. At the age of twenty-one he studied music for a year under the Cappelmeister Pabrich, at Potsdam, and in August, 1731, he became oboist in the band of the Guards, at Hanover. In August, 1732, he married Anna Ilse Moritzen. She appears to have been a careful and busy wife and mother, possessed of no special faculties which would lead us to attribute to her care any great part of the abilities of her son. She could not herself write the letters which she sent to her husband during his absences with his regiment. It was her firm belief that the separations and some of the sorrows of the family came from too much learning; and while she could not hinder the education of the sons of the family, she prevented their sisters from learning French and dancing. It is but just to say that the useful accomplishments of cooking, sewing, and the care of a household, were thoroughly taught by her to her two daughters. The father, Isaac, appears to have been of a different mould, and to him, no doubt, the chief intellectual characteristics of the family are due. His position obliged him to be often absent from Hanover, with his regiment, but his hand appears to have been always present, smoothing over difficulties, and encouraging his sons to such learning and improvement as was to be had.
His health was seriously injured by the exposures of the campaigns, and he was left, after the Seven Years' War, with a broken constitution.
After his final return home, in 1760, his daughter gives this record of him—