Month: April 2020

The stone mortared into place on September 29, 1982 was the cornerstone of the cathedral’s southwest tower. The date was the feast of St. Michael and All Angels or Michaelmas. It marked 41 years since construction on the cathedral had taken place. The stone cutting apprentices, whose numbers had swelled to about two dozen, had assembled an inventory of cut stone for the last three years. Some 2500 stones had been prepared and now was the time for these first stones to be set. The Very Rev. James P. Morton, dean of St. John the Divine noted that the first cornerstone for the cathedral had been laid in 1892 at the east end. The second, for the nave, was laid in 1925. Each formal cornerstone dedication has marked a significant phase of construction activity.

Cornerstone restarts construction

The cathedral had stopped building during World War II. Work was not resumed because the Episcopal Diocese felt that the erection of a lavish structure would be symbolically inappropriate until the poverty of its upper Manhattan neighborhood could be alleviated. Dean Morton, dean of the cathedral since 1973, realized that perhaps construction itself was the remedy. As a result if community residents were taught to build the cathedral themselves they could gain skills. Likewise this would knit together the cathedral and the community. The apprentices work under the master mason, James Bambridge, who said this of his charges:

All have learned faster than I would have expected – they are really more mature than the younger apprentices I have trained in England, and that makes all the difference.

-James Bambridge

The stone was a gift from Jerusalem Mayor Teddy Kolleck. The Jewish Mayor and the Episcopal Bishop Paul Moore Jr., pledged to exchange limestone blocks for their building projects. First of all the “Jerusalem stone” will be the cornerstone of the southwest tower. The exchange stone, the “St. John the Divine stone”, cut in the stoneyard, will be set among the oldest paving stones of Jerusalem’s Via Dolorosa. This is the traditional path to Calvary, which is in the process of restoration. The ceremony of the stones was held in January, 1981.

The Walk Across Amsterdam Ave

Aerialist Philippe Petit carried a silver trowel across Amsterdam Avenue on a high wire to Bishop Moore, who blessed the stone. Petit and the cathedral were not strangers. This story from The New Yorker: “Philippe Petit has been an artist-in-residence at the cathedral since 1980. He fell in love with the place when James Parks Morton, the cathedral’s charismatic and somewhat unorthodox Dean, invited the fledgling Big Apple Circus, with which Petit had appeared once or twice as a guest artist, to use the Synod House as its circus school for a few weeks. Petit told Morton he would like to do a high-wire walk inside the cathedral.

Morton, who knew about the association of cathedrals and tightrope walking in the Middle Ages, was all for it, but his trustees said no. (What if he fell?) Petit put up a cable anyway and did his walk. When he came down, the police arrested him for trespassing. They were taking him away in handcuffs when Dean Morton, who hadn’t witnessed the walk, appeared and told them to release the culprit. ‘He wasn’t trespassing,’ Morton told the cops. ‘He is an artist of this cathedral.’ Afterward, it seemed like such a good idea that Morton and Petit made it official.”

Part II – The Giant Lathe

To turn the large stone blanks from the granite by the sea into columns required a lathe of unheard of size, because each of the 310 ton raw stone blanks needed to be sculpted to 54 feet high and 6 feet in diameter. As a result the final column would weigh 160 tons. The church commissioned the design and construction of the lathe. It was designed and patented by E. R. Cheney and H. A. Spiller of Boston. It was built by the Philadelphia Roll and Machine Company of Philadelphia. Its construction was begun in December, 1899, and it was delivered at the quarry in May, 1900. It was erected at Vinalhaven under the supervision of J. W. Bourn, the foreman of the machine shop.

The lathe is 86 feet long and weighs 135 tons. It has a capacity to work a stone 60 feet long and a maximum diameter of 6 feet 6 inches. Eight cutting tools are used, each capable of taking up to a 3 inch cut so that the column can be reduced 2 feet each time the cutters traverse the entire length of the bed. In practice the cut was usually set at 1.5 inches. The result is a splintering or spalling of the face of the stone.

Dressing and Polishing the Column

When the column is dressed to shape, cup shaped devices are attached to the tool posts and filled with hardened steel shot. This gives the surface a rough polishing. Likewise, the final high polishing is done the same way using sand and powdered emery. The granite columns make 1.75 revolutions per minute during the operation of turning. During the polishing operation the column makes about 3 revolutions per minute. The countershaft to which the lathe is belted is driven by a steam engine of 50 HP. Finally each 300 ton blank will be reduced to 130 tons and take 6 weeks to complete.

The scientific, architectural, engineering and manufacturing communities followed this mammoth undertaking for months. Therefore the design, quarrying, turning and polishing of the granite by the sea and the lathe captured the attention and imagination of a large portion of the country.

The First Granite Stone Broke in the Lathe

It was found impossible to turn the columns in single blocks. The first three put into the lathe broke under their own weight after considerable work had been expended on them. The ends of the granite columns were held in large chucks or faceplates. Therefore the entire weight of the column was carried by these two faceplates, almost 60 feet apart. As a result therein was the problem as the first stone broke in the middle.

The designer of the lathe said that the proportions were to blame and that the design length would need to have a diameter of eight feet in order to sustain its own weight. It was also indicated that some areas of the quarry had a seam running through it which made it necessary to cut some stone across the grain. Various attempts were made to reduce the bending stress in the middle without success.

Also, numerous other plans were suggested by ingenious inventors to get the granite by the sea on a lathe. One of the most promising was to set the column on end on the center of a revolving table and turn it by tools traveling on a fixed vertical bed. While this plan may have been all right mechanically, the cost of a 75 foot stable tower to support the stone from deflection and carry the turning tools was not practical. The mere setting on end a block of stone weighing some 300 tons was a task not to be taken lightly.

“No Monolithic Columns for the New Cathedral”

In the end, the quarry insisted that monolithic columns would not be possible and the Board of Trustees had no alternative but to accept the new dimensions of a two part column. The lower piece would be thirty-eight feet long and weigh 90 tons. In contrast the upper piece would be 17 feet long and weigh 40 tons. The diameter of the columns would remain at 6 feet.

• Scientific American, January 12, 1901
• Engineering News, December 3, 1903
• Machinery Magazine, April, 1901