Arms used printmaking to express his passion for architecture, a subject that he studied at M.I.T. He specialized in etchings of medieval churches and cathedrals, hoping to convey the glory of earlier ages that endured in Europe's architecture. Arms made several trips to France, Spain, and Italy to draw such buildings. Beginning with studies of architectural details, he later rendered entire facades and a great number of buildings and their reflections in water. "Spanish Profile" depicts a cropped-in view of Puerta del Obispo, or Doorway of the Bishop, in the Cathedral of San Antolin in Palencia, Spain. This particular etching was one from a series that Arms completed of Spanish churches. A meticulous artist, Arms would work with three magnifying glasses and a common household needle to create his etchings. As a printmaker he was mostly self-taught, but his expertise as an etcher was without equal. He would often hone down phonograph needles to create lines that need magnification to see. The effect gives architecture a texture and life that few others could achieve.