The former James H. Proctor estate lies between County Rd and Fellows Rd., built by James H. Proctor in 1895. The Catholic Church purchased the property, where it was used as a novitiate by the Oblates of Mary Immaculate, and later became the Catholic school Don Bosco. Since 1999 the Proctor estate has been the home of New England Biolabs, which provides walking trails open to the public.
In 1638, Richard Jacobs received a grant of 40 acres on the southeast side of Mile Brook, bounded with the 40 acre farm of Richard Saltonstall on the northwest. In this rather remote location, Jacobs built his dwelling. The most direct way to Town lay over the Mile River and through the pastures to the way now known as Fellows Lane. He built a bridge over the river in about 1650. On Dec. 6, 1658 the town ordered that a highway be laid out through Mr. Saltonstall’s 40 acres and part of John Andrews’ farm, continuing across Richard Jacob’s Bridge over the River. In the early 20th Century Mr. Proctor built the beautiful brick arch bridge at the same point and named it “Saltonstall’s Bridge.”
Sources:
Historic Ipswich 
Went to high school there from 1964-1968. I certainly hope the still existing structures are protected by an historical designation. There were many historical pieces of John Proctor’s property in Mostly Hall and are hopefully still there. The mansion was dining rooms, a chapel and the residence of the priests and brothers and the stable at the bottom of the hoill was classrooms, a chapel, and dormitory. Salesian sisters lived in the caretakers house
I lived in the grand house of the Proctor Estate from 1972-1973 as a Salesian novice. The house and surrounding property were beautiful. I have many happy memories of living there.