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Embrasure.Nuremberg.. la porte Laufer de Nuremberg le long du boulevard extrieur on remarque encore des embrasures destines de trspetites pices d'artillerie et dont les ouvertures sont protges par des cylindres en bois pivots percs de trous comme les crneaux d'une des portes de Ble en Suisse ViolletleDuc Drawings by Eugne ViolletleDuc