I think they are hoof marks in the road

This picture shows the greyhound pub without the building down street from the pub, also you can see the return of the great wall of Wivenhoe hall turning into Clifton Terrace opposite the pub. Next door to the Greyhound, where the holly tree stands a small shop was built for Mr. King the butcher.
You have to left click on this image to see the quality

Wivenhoe memories collection.