Prendergast Preventorium Postcards Prendergast Preventorium No. 2462 Postcard. Caption on front: Prendergast Preventorium for Children, 1000 Harvard Street, Mattapan, Mass. Postally unused. ca. 1930 Facebook Twitter Print Friendly Skills Dorchester, Mattapan, Prendergast Preventorium Posted on December 7, 2022 ← Howlin Creatures, Mattapan W.E. Endicott School →