While grand ships with billowing sails made their way in the Hudson River, a crew in a modest tugboat kept watch on the high-traffic day on the water.

© Juan Arredondo for The New York Times

The USCGC Eagle, which leads the parade of tall ships in honor of America’s 250th birthday, is carrying a rare 1776 printing of the Declaration of Independence.

© Darryl Dyck/The Canadian Press, via Associated Press