The Alexander polynomial of a rational link

We relate some terms on the boundary of the Newton polygon of the Alexander polynomial Delta(x, y) of a rational link to the number and length of monochromatic twist sites in a particular diagram that we call the standard form. Normalize Delta(x, y) to be a true polynomial (as opposed to a Laurent polynomial), in such a way that terms of even total degree have positive coefficients and terms of odd total degree have negative coefficients. If the rational link has a reduced alternating diagram with no self-crossings, then Delta(-1, 0) = 1. If the standard form of the rational link has M monochromatic twist sites, and the jth monochromatic twist site has mj crossings, then Delta(-1, 0) = Pi(M)(j=1) (m(j) + 1). Our proof employs Kauffman's clock moves and a lattice for the terms of Delta(x, y) in which the y-power cannot decrease.