Joseph Wright of Derby and Dr Erasmus Darwin, the artist and his physician.

In 1767 at the time of his great "candlelight" paintings of science and the Enlightenment, The Orrery and The Air-Pump, Wright of Derby developed the illness that plagued him for the rest of his life and became a patient and life-long friend of Dr Erasmus Darwin. Wright's recorded complaints and the periodicity are highly suggestive of the major depressive illness, seasonal affective disorder.