The gravel is brought from Needham, near the line of Newton, a quarter of a mile from the Upper Falls Depot, and nine miles distant from Boston. One hundred and forty-five dirt cars, with eighty men, including engineers, brakemen and all, are employed, night and day in loading and transporting the gravel over the road. The trains consist of thirty-five cars each, and make, in the day time, sixteen trips, and in the night nine or ten, or twenty-five in twenty-four hours. Three trains are continually on the road during the day, and one arrives at the Back Bay every forty-five minutes. The excavators for loading the cars work by steam, and perform the work with rapidity and ease….
The time occupied in loading an entire train of thirty-five cars is about ten minutes. The excavators do the work of two hundred men. The process of loading the cars, though very simple, is curious and interesting. During the year the contractors have been at work, there have been taken out of the hills of Needham about three hundred thousand yards of gravel….
It is believed that the excavation and filling in are going on at a more rapid rate than has ever been known in the history of any similar contract in the country. The contractors make, in the Back Bay, on an average, about twenty-five hundred cubic yards, or forty-five hundred superficial feet per day. This is equal to nearly two house lots. About fourteen acres of land have been made already. At the rate the work is progressing, the hundred acres belonging to the State will be completed in about four years more time. The land made is measured on the first day of every month by an engineer, . . . and the contractors draw their pay once a month, averaging from ten to twenty thousand dollars….
As they settle now each month with the State, they receive, of course, deeds of land instead of cash. The Commissioners have sold in all about five hundred thousand dollars worth of land.
Ballou's Pictorial, May 21st, 1859, quoted in Boston: A Topographical History, by Walter Muir Whitehill and Lawrence W. Kennedy (Harvard University Press, 2000).