Before Abraham Lincoln took his marble seat in Washington, his face and hands passed through a red-brick workshop in the Bronx. Around it worked six Italian brothers, carving the President’s face for a 19-foot figure built from 28 blocks.

Daniel Chester French had conceived the image. He studied Lincoln’s photographs, and decided how the hands should rest and worked through models of increasing size. The model went to the Bronx because French trusted the Piccirillis to reproduce it precisely. There, the distinction between designing Lincoln and making him became less simple.

The brothers were not obscure in their own time. In 1935, TIME called them “the world’s greatest team of sculptors”. Their father, Giuseppe, had brought the family to New York in 1888 and opened a stone-carving shop beside their home. It eventually occupied a city block, but it still ran like a family place – with plenty of laughing and opera-singing among marble slabs and plaster casts. Furio and Orazio specialized in animals; Getulio ran the business; Attilio directed the artistic work.

This was how monumental sculpture was made at the time: a recognized artist supplied a model, and professional carvers enlarged it in stone. But enlargement was not photocopying. A detail that worked in plaster could fail at monumental scale. Every fold of Lincoln’s coat and line around his mouth required judgment, followed by a cut that could not be reversed. French supervised and added the finishing touches, but the chisels remained in Piccirilli hands.

Sculptors knew their skill even when the public did not know their names. The same workshop carved the lions outside the New York Public Library from Edward Clark Potter’s models. At the Metropolitan Museum, Mourning Victory names French as “artist” and the Piccirilli studio as “carver”. The labels preserve the hierarchy through which sculpture was made.

When Lincoln’s blocks were assembled in Washington, the seams nearly vanished. The face the brothers carved became familiar to millions. Ferruccio, Attilio, Furio, Masaniello, Orazio and Getulio did not.