Masonry was then estimated in “perches,” and by a little arithmetic, the modern contractor will learn that a perch was then equal to 25 cubic feet, or nearly a cubic yard. The 784 perches of masonry for the foundation were priced at $10 per perch, including “stones, hammering, mortar, laying, etc.”
The report of Baldwin contains no computations on the structural stability of the monument. If the modern structural designer wishes to investigate how near the safe limit the monument has been tested by Boston’s occasional hurricane winds, he has available the major dimensions given in the Baldwin Report, and the drawings of Willard’s classic Plans and Sections of the Obelisk from which to make this simple computation.
Such computation shows that the monument is so heavy that a hurricane wind has an almost imperceptible effect on its stability. When it is subjected to a 100-mile-per-hour wind, the resultant force is displaced only a fraction of a foot from the center of the 50-foot-wide foundation. The maximum load on the soil is about five tons per square foot—a safe bearing load on “the bed of clay and gravel which composes the soil of the Hill” as described in an old account. The same account speaks of “great pains having been used in loosening the earth, and in puddling and ramming the stones.” Surely, our construction ancestors would not have purposely disturbed the underlying soil, in an attempt to improve upon the natural bearing strength of one of the firmest of foundations: glacial hardpan. Like any good builder, they were undoubtedly merely puddling with water the earth backfill around the completed foundation.
Baldwin knew that granite would not deteriorate when exposed to the alternately hot and cold temperatures of Boston. Half a century later, the engineers who transported an Egyptian obelisk (one of the Cleopatra’s Needles) to Central Park, New York, learned that the lovely textured syenitic granite of the Nile Valley was markedly inferior to New England granite in weather resistance, although it had kept its surface intact for centuries in the mild climate of Egypt. To protect Cleopatra’s Needle in New York, a paraffin coating was found necessary.
Baldwin soon resigned from the building committee, partly because of the press of other work, but largely in protest against a clause which made its members, all of whom freely donated their services, financially responsible for the estimate. Promptly after accepting his resignation, the directors revised this clause. In reviewing the quaint old methods, the question arises: Would modern estimates be more accurate if the consulting architects and engineers had to pay for overruns?
Transient Cornerstone
On 17 June 1825, the cornerstone of the monument was laid with impressive ceremonies. As the colorful procession marched up Bunker Hill to the stirring rendition of “Yankee Doodle” by the drummer of Colonel William Prescott’s regiment, who, 50 years before, had been in the battle, the rear of the procession was just starting from distant Boston Common. The little Boston of over a century ago was crowded with visitors who had come from places as remote as South Carolina by stagecoach, sailing vessel, or on foot, to hear the great speech of Daniel Webster, President of the Bunker Hill Monument Association, and America’s first orator of the day. Years earlier, Chaplain Joseph Thaxter had paid the last offices to dying soldiers in the battle; now, he invoked God’s blessing on the young American republic, as 40 veterans of the battle sat in a place of honor.
The most important visitor, of course, was General Lafayette, who, as a good Mason, spread the mortar on the stone when it was laid by Most Worshipful Grand Master of the Grand Lodge of Massachusetts, John Abbot. As the battle’s only monument up to this date had been erected by the Masons, it was considered appropriate that the permanent monument should have its cornerstone laid with the Masonic ceremony. A little later, this procedure was sharply criticized during the Antimasonic period, which occurred before the monument was finished.[6]
[6] Joseph Warren, the outstanding hero of the battle, was Grand Master of Freemasons for North America.
Many of the spectators knew that the cornerstone records would later have to be moved, for the plans of the monument were hardly started. Now, the box with its old newspapers, Continental currency, and other data is within a stone at the monument’s northeast corner, and the original cornerstone stands in the center of the foundation.