In 1878, the Sisters of Loretto in Santa Fe, New Mexico, finished building a small Gothic chapel modelled on the Sainte-Chapelle in Paris. The architect was dead. The choir loft was twenty feet above the floor. There was no staircase. There was no way to put one in. Six master carpenters told them so. The Sisters began a novena to Saint Joseph, the patron saint of carpenters. They prayed for nine days.

On the morning of the ninth day, a grey-haired man arrived at the chapel door with a donkey and a small wooden toolbox. He did not give a name. He worked alone for three months. He used a saw, a hammer, a square, and small wooden pegs. He used no nails. He soaked the long planks of imported pale spruce in tubs of hot water before bending them. He built a staircase.

What he built has thirty-three steps. It rises twenty feet to the choir loft. It makes two complete turns of three hundred and sixty degrees in a tight spiral. It has no central support pillar. It is held together entirely by wooden pegs. The inner stringer is built of seven curved spruce segments and the outer stringer of nine, each joined to the next by hand-fitted pegs. The treads and risers act as diaphragms bracing the helix against itself. Modern structural engineers have written papers on it. It is one staircase.

When the carpenter finished, the Sisters went to the lumber yard to pay his bill. The lumber yard had no record of any order. They returned to the chapel. He was gone. They asked at every hotel, boarding house, and ranch in Santa Fe. No one had seen him. No one knew his name. In 1996, a retired US Forest Service wood technologist studied the staircase for fifteen months. He concluded the spruce was unlike any of the ten North American species. He named it Loretto spruce.

In the early two thousands, the historian Mary Jean Cook found a single line in the Sisters' 1881 logbook recording a payment of one hundred and fifty dollars for wood to a French-born rancher and carpenter named Frank Rochas. Rochas was murdered in 1894. His obituary in the Santa Fe New Mexican said he had built the staircase. He had not been paid for the work. The staircase is still there. Witnessed. Subscribe.