Month: September 2020

On a summer day in 1979, the first multi-ton block of Indiana limestone arrives in the unfinished stone shed. Master builder James Bambridge is at the controls of the overhead gantry crane. Apprentice Timothy Smith is in the background. The arrival of the first stone in the stoneyard signifies the beginning of the Dean Morton era of stonework.

The stone along with several smaller ones came from the Indiana Limestone Company in Bedford, Indiana. Once on the ground in the stone shed, the stone received the blessing of the Diocesan Bishop Paul Moore Jr.

The arrival of the first stone was accompanied by some smaller stones. Master Mason Chris Hannaway used the smaller stones to begin teaching the newly hired apprentices. The first skill involved handling the mallet and a broad chisel. Hannaway taught the apprentices the chosen finish for the exposed front side of the stone. Boasting is the name for that finish.

A boasted or droved finish is a very common type dressing of stone. The surface of the stone is covered with parallel marks that may run in any direction. A boaster, which is actually a wide edged chisel, is used for this purpose.

Fast Forward From The Arrival Of The First Stone

One sunny afternoon, years later, stoneyard manager Eddie Pizarro, who grew up in Spanish Harlem, picked his way through a side yard littered with limestone blocks. Those blocks were waiting to be hoisted 200 feet up the South Tower. He ticked off the names of the men who had worked on each piece.

“I can tell from the boasting marks, he explained, noting that the lines the chisel leaves are different for each person. “I can even tell you what kind of mood the carver was in the day he did it. When you work on a stone, you put your heart and soul into it. The stones here will tell stories for centuries to come.”

– Eddie Pizarro

• Special thanks to Pamela Morton and Tim Smith for providing photos
• Smithsonian, December 1992, Vol 25 number 9

The plan to move services from the Crypt to the Crossing caused several changes. Temporarily abandoned was the erection of the Lantern and Spire. Enclosing the openings to the future North and South Transepts was also necessary. Work began on a temporary dome over the Crossing, America’s largest dome.

The Guastavino Company was pioneering the erection of domes and vaulted ceilings of thin terra cotta tiles. They had been involved with the Cathedral since 1900 starting with the ceiling in the crypt. They also had put a barrel vault in the choir and the chancel.

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The dome, begun in 1909, is one of the largest masonry domes in the world. It is about 135 feet in diameter, measured across the lower part of the spherical surface. The crown is 200 feet above the floor of the building. It took 3 months and 16 days to complete the job. The dome consists entirely of burnt clay slabs 6 x 15 x 1 inch. Portland cement bonded the clay pieces. This therefore created a monolithic dome shell of unprecedented thinness. The dome construction didn’t involve any scaffolding or falsework.

The Process

The workers laid up the thin terra-cotta slabs in successive circular layers. The joints broke vertically and laterally and formed a hemispherical dome which surmounts the four great arches. The novel method of construction saved great expense by avoiding the erection and removal of heavy scaffolding and falsework. As well, no scaffolding meant reduced risk to workers associated with these tasks.

The lower portion of the dome springs from the four corners of the great granite arches. From these four starting points upward the successive layers of tile widen rapidly over the curve of the great arches. They eventually converge in a perfect circle at their crown. This was not the use intended for the arches. Rafael Guastavino Jr. had to design the dome using those existing structures.

Finding and Using the Center Point for America’s Largest Dome

They threw 1/4 inch cables across from the the center of the crown of each of the four granite arches. This then established the center point for America’s largest dome. They intersected at right angles exactly in the central point of the dome’s diameter. Engineers accurately determined the point with transit and level observations. Turnbuckle attachments rendered it possible to adjust for temperature variations. The engineers attached a 4 inch square steel plate with a center hook to the intersection of the cables. From this hook a fifth cable extended to an 800-pound weight at the floor. This weight acted as a guy to maintain the center point. The threaded end of the hook extending through the plate served for the attachment of the steel tapes. These tapes indicated the circumference of the dome and the hemispherical curvature.

Stretching these steel tapes determined the vertical and lateral curvature for laying each course. They went from the established center point to the interior dome surface. These tapes were marked for one half the diameter of the hemisphere. They instantly indicated the exact position where each tile should be laid to form its part of the hemisphere. The dome is six tiles in thickness at the base, or about seven and a half inches. This decreased to three courses or four inches at the top.

The Unique Dome Completed

The work progressed rapidly and the materials sustained their weight and that of the mechanics without the slightest mishap. According to every known theory, work created in this manner would fall of its own weight. Each morning, as the artisans resumed work, the material laid the previous day was found to have acquired such rigidity as to be capable of supporting their weight and the fresh construction. The dome was originally intended to be up 10 years. America’s largest dome has lasted over 100 years.

This post was not about divine stone, but about its cousin, divine clay

• Archives of the Cathedral
• Irma and Paul Milstein Division of United States History and Genealogy, The New York Public Library. Manhattan: Amsterdam Avenue – Cathedral Parkway
• Museum of the City of New York
• Zawinsky, N., Fivet, C., & Ochsendorf, J. (2017). Guastavino design of the 1909 thin brick dome of the Cathedral of St. John the Divine. Construction History, Vol 32(2), 39-66 dog:10.2307/26476167
• Scientific America, October 30, 1909, Scientific American Supplement N0. 1765
• L. Ramazotti, La cupula para San Juan el Divino de Nueva York de Rafael Guastavino. Las bóvedas de Guastavino en America, S.Huerta (ed.) Madrid Inst. J de Herrera, 2001

“We are all Stardust,” so writes author William Bryan Logan, quoting his friend Jim Morton. Logan additionally acknowledges Dean Morton for making that book possible when he invited Logan to become a writer-in-residence at the Cathedral of St. John the Divine. Speaking of Dean Morton:

“He has been an example to me of work pursued tirelessly and with deep good cheer.”

– William Bryant Logan

That book, Dirt, the Ecstatic Skin of the Earth, is part theology, part philosophy and all science about our planet. He writes about stone, rocks, silt, sand, and clay in a way that makes you want to go into your backyard and look closer and smell it. Wind and water and billions of years write the history of our dirt. Whether you are a quarryman, farmer, or clay artist, you will want to read his inspiring thoughts. The “Stardust” alludes to the fact that everything on earth, including us, is from stardust.

From his office on the triforium level, to his friendship with Jim and Pamela Morton he spent the better part of a decade at the Cathedral. One of the essays is about the foundations of cathedrals. Therefore it provides a great deal of insight into the beginnings of the construction of the Cathedral of St. John the Divine. Almost everyone likes to look at the vaulted spaces and the arches and buttresses. They all admire the windows, stonework and the carvings. Admiration is rarely a word that is used regarding the foundations.

Dig it and be Done

It looked like a simple matter, writes Logan. Beneath the shallow overburden of loose soil should have been solid metamorphic stone. Excavation continued to reveal twisted and fractured schist. The church’s elders were more than concerned. They were supposed to be building a grand cathedral, not digging an endless hole. Then, the industrialist J.P. Morgan wrote a blank check. He said “Dig it and be done.” That check covered what in today’s dollars would be $20 million.

Across the street, St. Luke’s Hospital began its foundation dig at the same time as the Cathedral. The Hospital was built and dedicated before the Cathedral’s foundation was done. The dig went down 72 feet in spots before bedrock was found. Finding that bedrock was good because as Logan indicates the unfinished Cathedral weighs in at 253,000 tons. “The weightiest Gothic undertaking ever”.

Stardust to Dirt Author

William Bryant Logan is the author of Sprout Lands, Oak, Air and Dirt, the last of which was made into an award-winning documentary. He is on the faculty of the New York Botanical Garden as well as a regular garden writer for the New York Times. His informative web site can be found here

• Special thanks to the artist and gallery owner Betsy Williams for leading us to this impressive book. Her site is here.