Last touched 2001 December 6
Originally published in M-111, the Newsletter of the Richland (Ohio) Astronomical Society
Reflections in the Eyepiece
By Robert Bunge
In many ways, William Herschel was the father of amateur astronomy. As a professional musician living in Bath, England in the 1770s, he over came great odds to discover Uranus with a telescope of his own make. After that discovery, he was given the title of Royal Astronomer and spent the rest of his life working as a professional astronomer.
Much has been written about William, and also his son, John. Most modern amateurs have either heard about the Herschels, or have read any number of articles in magazines.
I noticed, a few years ago when I came across a copy of Herschel at the Cape -- about John Herschel's years spent at the Cape of Good Hope in South Africa (1835-38) -- that the book included the text of several letters from John Herschel's aunt, Caroline Herschel. While reading those letters, it struck me that Caroline had been a very special woman.
I'll wager that if most amateurs are asked to say something about Caroline, they would reply that she is best known for the discovery of several comets. From reading those letters, I decided there was a lot more to Caroline than just a few comets.
I was right.
I was very lucky to find and borrow a copy of Memoir and Correspondence of Caroline Herschel, by Mrs. John Herschel, printed in 1876, almost thirty years after Caroline's death on Jan. 10, 1848. At the time, she was 98, having been born in 1750.
A pleasure, to read, the book is packed full of delightful information to amateurs. As a deep sky observer, the information about her bother was fascinating. As a telescope maker, tidbits about William Herschel's mirror making technic shed light on methods that haven't changed that much in 200 years. As a amateur historian of astronomy, and long time follower of the Herschels, the book delivered a sense of personally about these famous people that is rarely matched.
I like to share what I learn, so I picked just a few of hundreds of quotable sections from her diaries. What I have done is woefully inadequate. The only real way to do it justice would be for some enterprising publishing company to reprint it.
Born in Hanover Germany, Caroline joined her brother in Bath England in August of 1772. She was suppose to help her bother in his successfull music business as a singer. The winter months were busy in Bath. High society Britishers visited the resort town known for it's roman baths to pass the cold, wet months in comfort. But she soon found that William had more than just music on the brain;
"But I was greatly disappointed; for in the consequence of the harassing and fatiguing life he had led during the winter months, he sued to retire to bed with a bason of milk or glass of water, and Smith's "Harmonics and Optics,"Ferguson's Astronomy," & c., and so went to sleep buried under his favorite authors; and his first thoughts on rising were how to obtain instruments of viewing those objects himself of which he had been reading."
Not one to sit on his hands, William started planning;
"It soon appeared that my brother was not contented with knowing what former observers had seen, for he began to contrive a telescope eighteen or twenty feet long, (I believe after Huyghen's description)..."
For you TM's out there, you think WE have a problem getting parts: there were no advertisements in glossy magazines in the 1770s;
"... had to amuse myself with making the tube of pasteboard for the glasses which were to arrive from London, for at that time no optician had settled at Bath. But when all was finished, no one besides my brother could get a glimpse of Jupiter or Saturn, for the great length of the tube would not allow it to be kept in a straight line."
William wasn't happy with the refractors he built. Instead, he decided to build reflectors, with metal mirrors;
"About this time he bought of a Quaker resident at Bath , who had formerly made attempts at polishing mirrors, all his rubbish of patterns, tools, hones, polishers, unfinished mirrors, &c."
But, these mirrors were all small. He learned the only way to get bigger mirrors was to make them. Of course his new hobby was expensive, and life was to be lived. William spent every spare moment away from music with his telescope;
"But every leisure moment was eagerly snatched at for resuming some work which was in progress, without taking time for changing dress, and many a lace ruffle was torn or be spattered by molten pitch, &c."
But, Caroline had found a role. She tended to her brother. Her skill at penmanship was incredibly useful in an age before copy machines;
"For my time was taken up was so much taken up with copying music and practicing, besides attendance on my brother when polishing, since by way of keeping him alive I was constantly obliged to feed him by putting the victuals by bits into his mouth. This was once the case when, in order to finish a seven foot mirror, he had not taken his hands from it for sixteen hours together."
Sixteen hours? Wow! That's a lotta trips around the old barrel! But, seriously, William was just like us. He caught aperture fever. After much planning, he and his older bother Alexander (who was very much involved in all this astronomy stuff too) had plans to build a telescope that was thirty foot long. William's six and ten foot scopes ranged from five to ten inches in aperture. His twenty foot telescopes were 12 to 18 inches. Of course he had to cast the metal mirrors, because there was no other source;
"But, though at times much harassed with business, the mirror for the thirty-foot reflector was never out of his mind, and if a minute could but be spared in going from one scholar to another , or giving one the slip, he called at home to see how the men went on with the furnace, which was built in a room below, even with the garden."
His work in astronomy had not gone unnoticed, even before the discovery of Uranus. Learned people were attracted to the Herschels, and they all spent much time talking and teaching these people. Work on the thirty foot continued;
"The mirror was to be cast in a mould of loam prepared from horse dung, of which an immense quantity was to pounded in a mortar and sifted through a fine sieve. It was an endless piece of work, and served me for many an hour's exercise; and Alex frequently took his turn at it, for we were all eager to do something towards the great undertaking. Even Sir William Watson would sometimes take the pestle from me in the work-room, where he expected to find his friend, in whose concerns he took so much interest that he felt much disappointed at not being allowed to pay for the metal. But I do not think my brother ever accepted pecuniary assistance from any one of his friends and on this occasion he declined the offer by saying it was paid for already."
Over the years, I had often heard of the following tale. It was interesting to hear Caroline's version;
"...the mould, &c., in readiness, a day was set apart for casting, and the metal was in the furnace, but unfortunately it began to leak at the moment when ready for pouring, and both my brothers and the caster with his men were obliged to run out at opposite doors, for the stone flooring (which ought to have been taken up) flew about in all directions, as high as the ceiling. My poor brother fell, exhausted with heat and exertion, on a heap of brickbats. Before the second casting was attempted, everything which could ensure success had been attended to, and a very perfect metal was found in the mould, which had cracked in cooling.
On March 13, 1781, William discovered what he first thought to be a comet. What else could something that moved against the sky be? It proved to be Uranus. By May, the Herschel's lives would be changed forever;
"...from the letters we received, we could learn nothing but that he had been introduced to the King and Queen, and had permission to come to the concerts at Buckingham House, where the King conversed with him about astronomy."
The King liked William. After a period of thinking about what to do, William decided to give up music and make the jump into the professional community;
"...he chose to be Royal Astronomer, with a salary of 200 (English pounds) a year. Sir William Watson was the only one to whom the sum was mentioned, and he exclaimed, "Never bought monarch honour so cheap!" To every other inquirer, my brother's answer was that the King had provided for him."
One of the changes in Caroline's life was there were times now that William was not home. Caroline's life was carrying for her bother, both in the home and as his assistant at the telescope. What was she to do when he was gone, but clear skies were at hand? She started sweeping for comets in Aug. 1782 with a pair of opera glasses. Six months later, in July of 1783, she got her own telescope;
"I began to use the new Newtonian small sweeper, but it could hardly be expected that I should meet with any comets in the part of the heavens where I swept, for I generally chose my situation by the side of my brother's instrument, that I might be ready to run to the clock or write down memorandums."
William added to the family coffers by building telescopes for people. Apparently he charged a fortune, but built many. Most were built for royalty -- not always English -- but very rarely were they used! Production of these scopes was a hot topic. It took time from astronomy and stressed his health;
"In the long days of summer months many ten and seven foot mirrors were finished; there was nothing but grinding and polishing to be seen. For several ten foot had been cast with ribbed backs by way of experiment to reduce the weight in large mirrors. In my leisure hours I ground seven foot and plain mirrors from rough to fining down and was indulged with polishing and the last finishing of a very beautiful mirror for Sir William Watson."
The comment about the ribbed mirrors is interesting in lieu of how only now, more than two hundred years later, we are just beginning to see such mirrors available to the amateur community.
On the death of William in Aug. 1822, Caroline lost direction in life. It wasn't the first time. When William was married, she suddenly found herself without the job of caring for her bother. Moving back to Hanover after his death, she spent the rest of her days in communication with astronomical friends from around the globe. Much time spent making copies of her brother's list of nebula he discovered -- the base of the modern Revised New General Catalogue. She was also involved in making copies and ferreting out mistakes in star catalogues and other astronomical busy work to be done armed only with a pen.
I wish there was room for more. The book includes letters to and from fellow observers about her comet discoveries. Perhaps her most famous is now known as Encke's comet -- the shortest of the short period comets.
But Caroline Herschel was more than a comet hunter. She was the life assistant of her brother, which allowed him to spend the time with the construction the largest telescopes of the day. William also single handedly discovered thousands of deep sky objects. Her attention to detail is best seen in the accuracy of the published observations of William, and the few mistakes found in them.
It was this work, and not so much the comets that got her a honorary membership in the Royal Astronomical Society, (One of the first two women to reach that status) and later receive gold medals of honor from the Royal Society and other astronomical societies.
She was awarded the medal from the Royal Astronomical Society at a time when John Herschel was president of the organization. Knowing that she would be upset, he said this in a letter to her;
"...Before this reaches you, you will have got it (the medal). Pray let me be well understood on one point. It was none of my doing. I resisted strenuously. Being in the situation, I actually hold, [refused to vote as President] I could do no otherwise."
But in a reply to John she was true to her brother;
"I have no time or inclination to think much on this subject, else I could say a great deal about the clumsy speech of the [Vice-President of the Society who announced the award]. Whoever says too much of me says too little of your father! and only can cause me uneasiness."
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