In a marvellous and most fascinating book, The Age of Wonder by Richard Holmes (Pantheon Books, New York , 2008), I have been reading about the eighteenth century astronomer, William Herschel.

His extraordinary dedication to making better reflector telescopes and extending astronomical knowledge led to his being appointed King George III's Personal Astronomer. He discovered Uranus, the seventh planet and the first to be discovered since the time of Ptolemy, and became a most celebrated member of the Royal Society.

His original profession was not astronomy but music, which he learned mainly from his father in Hanover. He was a gifted musician, composer, and music teacher, who met with considerable success in England, especially in Bath. However, his passion was amateur astronomy to which he dedicated more and more time. And this is where I found it so fascinating: his prior skill in sight reading in music and his dedication to practice in music-making helped make him, he believed, a far better astronomer.

Some people claimed that his finding another planet was mere chance, and he reacted defensively. He wrote on 7th January 1782, "I do not suppose there are many persons who could even find a star with my (magnifying telescope) power of 6,450, much less keep it if they had found it. Seeing is in some respects an art, which must be learnt. (My emphasis). To make a person see with such a power is nearly the same as if I were asked to make him play one of Handel's fugues upon the organ. Many a night have I been practising to see, and it would be strange if one did not acquire a certain dexterity by such constant practice." (Again, my emphasis.)

Richard Holmes further wrote of Herschel's skill in identifying stellar patterns as being honed by his many years of sight-reading musical scores. "Or more subtly, the brain that was trained to recognise the highly complex counterpoints and harmonies of Bach or Handel could instinctively recognise analogous stellar patternings." (page 115)

This fascinating account drives home to me the value of practice in whatever artistic venture in which one is engaged. The eye, the ear, the hand and thus the brain all improve with constant training . Herschel was indeed a shining example of the virtues of practice.

The Age of Wonder is a marvellous book through which to be reminded of these virtues.