Exodus 10:21

And the LORD said unto Moses, Stretch out thine hand toward heaven, that there may be darkness over the land of Egypt, even darkness which may be felt.

Stretch out thine hand ... darkness. Whatever secondary means were employed in producing it-whether thick clammy fogs and vapours, according to some, a sand storm, or the chamsin, according to others-it was such that it could be almost perceived by the organs of touch, and so protracted as to continue for three days, which the chamsin does (Hengstenberg, Osburn). 'It was a gross and palpable darkness; the longer night that the book of God specifies-a silent, solitary, melancholy, inexplicable season. No murmur disquiets the air, no man hears his name, no birds sing, except the owl and the night-raven, which creak only dismal things' (Adams).