ever great may be his desire to learn, or however closely surrounded with such printed symbols of ideas he may be!
The transfer from the printed page to the cortex of the brain means long and continuous labor, years of it, unnumbered days and nights of it. There cannot be a rule for the actual study of all books. Some books require concentrated attention for their mastery, and some do not. Some call for thoughtful revery running along with their reading, and some demand concentrated attention to the books' ideas themselves, if the reader would become really learned.
The amount of time actually spent on some lessons in seventy-five classes in the University of Iowa has been reported by Professor Irving King ("School and Society", December 4, 1915). Of the 2567 students who answered the questions of the investigator about 61 per cent used one and a half hours or less on the particular lesson assignments from which the statistics were made. Eight per cent used one half hour or less, and 5 per cent three hours or more. If we may take these figures as average values (and they are the only available data at present and as far as they go surely wholly reliable) we can judge fairly well
