Morgue
,a dead-house, is generally associated with mors (death), but this is a blunder, as the word means visage, and was first applied to prison vestibules, where new criminals were placed to be scrutinised, that the prison officials might become familiar with their faces and general appearance.
“On me conduit done au petit chastelet, où du guichet estant passé dans la morgue, un homme gros, court, et carré, vint à moy.”—Assoucy: La Prison de M. Dassouch (1674), p. 35.
“Morgue. Endroit où lʹon tient quelque temps ceux que lʹon ecroue, afin que les guichetiers puissent les reconnaitre ensuite.”—Fleming and Tibbins, vol. ii. p. 688.