sentences:  The house is built from squared beams connected by mortise and tenon joints, the characteristing method of timber frame construction; the style differs from both log cabins, which used rounded logs, and balloon framing, which typically used nails and smaller beams.The beams were hewn rather than sawn, an unusual technique that likely resulted from Pittsfield's lack of a sawmill in 1838.Well-preserved timber frame houses are rare in Illinois, and the Shastid House is the only surviving example of the method in Pittsfield.