15: Ship's positioning system
26: Marble bridge over the Grand Canal
32: It's involved in inspiration
44: Sources of inspiration
45: Farmer's hangout, in a children's song
47: Cause of a Macy's riot?
50: Lighted sign contents
52: Condensation phenomenon
56: ___ up (quits talking)
58: Pertaining to the sole of the foot
64: Long-necked instrument
70: Golden Rule preposition
72: Gets a signature on the dotted line, perhaps