the museum model

In his notes, Leonardo remarks that, with a linen curtain shaped into a pyramid having a base 12 yards (about 7 metres) across and equally deep, if it is stiffly held open, "ognuno si potrÓ gettare da qualsiasi altezza senza alcun rischio" (anyone can jump from no matter what height without any risk whatsoever).
Codex Atlanticus, sheet 1058