 His study, "Die frühmittelalterliche und romanische Baukunst" (1926) exemplifies his categorical distinctions between Romanesque and Gothic architecture - the former being "additive", "frontal", and "structural" while the latter is "partial", "diagonal", and "textural".In 1933, Frankl's enthusiasm for medieval architecture led him to join a group of medievalists at the 13th International Congress of the History of Art in Stockholm to view the only gothic church whose original wooden arch scaffolding was still extant.The Nazis terminated Frankl's position in Halle in 1934.