Made a short visit to the Clock Tower with little to see upon arrival.  A few passing gulls and Double-crested Cormorants in flight over the Merrimack River.  Then a bolt of speed came in from the NW with a definitive flight pattern that could only belong to a peregrine.  Sure enough, the adult male arrived and with legs outstretched, landed on an upper ledge, above the west clock face, and in the shade.