A method for the elementary teaching of arithmetic by numerical intuition produced by apparatus (Machine-translation by Google Translate, not legally binding)

摘要

"A METHOD FOR ELEMENTARY EDUCATION IN NUMERICAL INTUITION PRODUCED BY APPARATUS ARITHMETIC" characterized by the representation of units of numbers of any order and class by means of diverse elements on rods or vertical housings located in horizontal bars which form together with lateral vertical bars a supporting frame of the constituent elements of the auxiliary apparatus of the method. (Machine-translation by Google Translate, not legally binding)