 The operation of division with polynomial  functions was introduced in MAL but never successfully developed  in his algebra of logic—there are no equational  laws for how to deal with division. It was abandoned in LT  except for being  frequently used as a mnemonic device when solving a polynomial equation.    From the Expansion Theorem and the properties of constituents he showed that the modulii of the sum/difference/product of two elective functions are the sums/differences/products of the corresponding modulii of the two functions. 