This pastel drawing shows William Thomson, first Baron Kelvin, an important British physicist who invented the Kelvin scale of temperature and pioneered sub-marine telegraphy. In 1824 he joined Glasgow University, aged only ten, and later continued his studies at Cambridge, returning to Glasgow as Professor of Physics in 1846. Between 1846 and 1889 he published around 600 papers and created numerous inventions. Thomson is arguably most famous for the Kelvin scale of ‘absolute temperature’, where zero Kelvin is considered the lowest possible temperature of anything in the universe. He was knighted in 1866 by Queen Victoria for his research in and contributions to the installation of the Atlantic telegraphy cables, which improved intercontinental communication.