From The Connecticut River Valley in Southern Vermont and New Hampshire: Historical Sketches by Lyman S. Hayes, Tuttle Co., Marble City Press, Rutland, VT., 1929, page 57:
A BIRD'S FOOTPRINT IN ROCK AT THE FALLS
Until about the beginning of the 19th century, a natural curiosity in a rock at Bellows Falls excited interest in scientific circles of the country. Near the head of the canal, upon the point of rock extending into the Connecticut river, between the canal and the foundation of the present Sullivan railroad bridge, there was the clearly defined footprint of a huge bird of some unknown species. It was described as an exact reproduction of an exaggerated hen's track and measured five feet in length. It had an appearance like that of a bird stepping into a plastic substance, as of the rock when in its formative stage, and ever thereafter remaining as left by the imprint of the foot. It was in a particularly hard specimen of gneiss rock, which at that point was in layers of about one foot thick. For many years this curiosity attracted the interest of visiitors, travelers and scientists. It was described in diffferent publications of the day, and strangers coming here frequently requested to be guided to its location as one of the attractions of the place. About the year 1800, the faculty of Dartmouth College arranged to secure the curiosity for their museum. A time was set for the removal to Hanover of the section of stone in which it was embedded. Some unappreciative and jealous persons, learning of the plan to remove it, a day or two before the proposed visit blew the interesting speciimen into fragments with powder, rather than have it taken from this vicinity.