The hospital is constructed largely of granite from Chelmsford, Mass. In the early 1800s, stonecutters on the North Shore had developed new, more efficient methods of quarrying stone that made granite much more readily available. It was also a clear choice for the hospital building because it looked more impressive than wood or brick and is a durable, fireproof material suitable for construction that is built to last. The stone was transported by river to the state prison in Charlestown, where it was shaped into blocks for building by prisoners. While the Massachusetts prison labor program that exists today, creating industrial and commercial products, was chartered in 1887, prison labor was not uncommon in the early 19th century, either. This image of stone-cutting at the state prison is from the 1850s.