Kelvin - Life, Labours and Legacy - R. Flood, et - Samples of art and ...

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William Thomson:
An Introductory Biography
Mark McCartney
AN IRISH CHILDHOOD
It was a family joke that William Thomson had two birthdays, and once while
signing his name in a birthday book, as William Thomson on the 25 June, and
Kelvin on 26 June he quipped ‘It is convenient to have two birthdays when you have
two names!’ 1 It is not quite clear how the confusion arose, and though in childhood
his birthday was celebrated on 25th we have it on the authority of his father that
William Thomson was born on the 26 June 1824 at 5 a.m., and on the authority
of his eldest sister Elizabeth that the day of his birth was one of beautiful summer
sunshine.
Thanks to the labours and love of their father, Dr James Thomson, William and
his brothers and sisters enjoyed a happy childhood, steeped in knowledge and learning,
which their father took every opportunity to impart.
Dr James Thomson, born in 1786 in a farmhouse outside Ballynahinch, was
the youngest—by ten years—of five children. His two older sisters taught him
to read and he taught himself arithmetic from a copy of John Bonnycastle’s The
Scholar’s Guide to Arithmetic, but also attended a local day school run by a Dr Edgar.
He went on to study at Glasgow University, coming home each summer to work
in Dr Edgar’s school, and by 1815 he was Professor of Mathematics at the newly
opened Belfast Academical Institution (today a school, but in the early days of its
existence a school and college combined, with the college functioning like a small
Scottish university).
James was hard working and ambitious. Opposite the Academical Institution he
built two houses, one to raise his family in, and one to rent out. He wrote a range
of successful textbooks—on topics such as arithmetic, calculus, trigonometry, and
geography (rising at 4 a.m. in the morning to work on them) and he never missed