“Sleeplessness is one of the torments of our age and generation.” You might presume that this is a quote from a contemporary commentator, and no wonder: the World Health Organisation has diagnosed a global epidemic of sleeplessness, and it is difficult to escape accounts, both popular and scientific, of the dangers to health of our 24/7 lifestyle in the modern digital age. But it was actually the neurologist Sir William Broadbent who wrote these words, in 1900.