He was unable to return to teaching until at least 1929. However, in the early 1930s, he continued to issue criticisms of the railroad industry labor practices. In 1931, he had also testified at a Senate banking inquiry, urging the curbing of investment trusts. In 1932, he appeared at the Senate Banking and Currency Committee, and demanded public inquiry into the financial affairs of corporations and authored a series of articles in the "New York Times" stressing the importance of railroad economics to the country's economy. Yet, by the end of the year he had suffered another nervous breakdown, and retired in early 1933.