Pathological anatomy had had no more than a shadowy existence, on the edge of prohibition, sustained only by that courage in the face of malediction peculiar to seekers after secret knowledge; dissection was carried out only under cover of the shadowy twilight, in great fear of the dead: at daybreak, or at the approach of night', Valsalva slipped furtively into graveyards to study at leisure the progress of life and destruction'; later, Morgagni could he seen 'digging up the graves of the dead and plunging his scalpel into corpses taken from their coffins'.'