Last month I set out to research the Bath Road and stayed for a few days in Bath. Although I hadn’t intended finding out about the astronomer Sir William Herschel I found he was hard to miss and soon realised that his would have been a name on everyone’s lips in Georgian London – the instigator of a Georgian “comet craze.”
Friedrich Wilhelm Herschel was born in 1738 in Hanover, Germany which was, at the time, also ruled by the King of England, George II. His father was an army musician and he followed in his footsteps, joining the band of the Hanoverian Guards. When the French occupied the state in 1757, he came to England, embarked on a career in music and in 1766 he was appointed organist of a fashionable chapel in Bath.
His music seems to have been accompanied by an interest in mathematics which led him to the science of optics and the construction of telescopes and from there to the study of the night sky.
Before long William was determined to study the distant celestial bodies, and as this meant he needed telescopes with large, exceedingly expensive, mirrors he began to produce his own from discs of copper, tin, and antimony. What he wanted proved beyond the local foundries so he started to cast his own in 1781 in the scullery of his house. His early efforts resulted in floods of molten metal across the floor – the cracked flagstones are still visible in the photograph below– and almost poisoned himself with the toxic fumes. Eventually he was making telescopes which were superior to those at the Greenwich Observatory.
His sister Caroline, a plain little woman whose growth had been stunted and face pockmarked by childhood illnesses, escaped a life of domestic drudgery at home in Hanover when William invited her to live with him in Bath in 1772. Like William she was an accomplished musician and gave public performances.
Soon she was drawn into her brother’s astronomical work, sitting outside in their garden (shown below) for hours at night taking notes as he studied the sky.
Herschel’s fame began to spread but he became nationally known when, in 1781, he saw something that he recognised as highly unusual – he had discovered a planet. He called it after the king, but the astronomical establishment insisted on Uranus – the first new planet to have been discovered since ancient times.
William was awarded the Copley Medal, elected a Fellow of the Royal Society, given a royal pension of £200 which enabled him to devote himself entirely to science and was appointed as astronomer to
George III. The Herschels moved to Datchet, near Windsor Castle because the royal family insisted on having ‘their’ astronomer on hand to give demonstrations.
He gave his sister her own telescopes and, as well as recording his observations, she began her own work, studying nebulae and the deep sky, searching for comets and making her own highly significant contributions to the science. Eventually they moved to Observatory House Slough in 1786 (demolished with a fine disregard for history in 1960) which sat right by the Bath Road. A vast shopping centre now covers the site.
In 1789 he constructed in the garden a vast telescope (left) with a focal length of 12 metres (40 feet). Herschel was knighted in 1816 and died in 1822 while Caroline lived to be 98, dying much honoured by the scientific community in 1848. She held the record for the number of comets discovered by a woman (eight) until 1987. (She is caricatured, right)
With the flood of new astronomical sightings the public interest was caught and “Comet-mania” swept the country. Gentlemen could purchase a cometarium to study them, an expensive little instrument. “A Catalogue of Optical, Mathematical & Philosophical Instruments made and sold by W & S Jones 135, next Furnival’s Inn, Holborn London” lists them: “Cometariums for exemplifying the motion of comets from £1 11s 6d to £5. 5s.”
Comets became a source of popular entertainment, speculation, wild theories – and proved irresistible to the cartoonists.
The Herschel Museum of Astronomy at 19 New King Street, Bath preserves William and Caroline’s Bath home, right down to the cracked paving slabs and the garden where they did so much of their early work. (Their dining room is shown below with a full-size replica of one of the telescopes Herschel used in the room beyond.)