Single sheet. Hand col. ms. Medium: Edges bound with green silk and whole folded into slip case covered with green marbled paper. Physical description Note: Has a hinged flap to show the proposed fortification. Scale: [ca. 1:7 000 (bar)]. Cartographic Note: North at 135 degrees. 'Sir Alesander Ball's Summer Residence' is marked. Sir A Ball assisted in the reduction of the French garrison of the forts at Valetta in the period 1798-1800 and was Governor of Malta from 1801 until his death in 1809.