The Swiss physician Johann Jakob Wepfer (1620–95) showed that apoplexy is due to cerebral haemorrhage.¹ Vascular engorgement or congestion, not occlusion or stenosis, was at that time thought to cause non-haemorrhagic (serous) apoplexy. Indeed even at the turn of the 19th century, Pinel and others classed apoplexy as a form of cerebral neurosis. The distinction between thrombosis and haemorrhage was unclear until the mid 19th century,² despite the clinical and pathological …