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<br />-14- <br /> <br />area of 1500 square miles was prohibitive. It is also questionable <br />whether the procedures could be performed reliably by non-specialists. <br />Instead, a more easily replicated method has been selected whereby only <br />those channels designated as permanent or intermittent on 1:24000 topo- <br />graphic quadrangles are included. This approach is judged to be the <br />most uniform and reliable alternative, despite the likelihood of differ- <br />ent interpretations by the various cartographers who produced the maps. <br />Once the watershed and drainage network were delineated, values of <br /> <br />basin area, basin perimeter and the total length of stream channels were <br /> <br />obtained by means of an electronic graphics calculator having a linear <br /> <br />resolution of 0.01 inches. The drainage network was evaluated further <br />in terms of its morphometric properties. Two general approaches have <br />become prominent, the one based on stream orders and the other based on <br /> <br />stream magnitude. With regard to the process-response model described <br /> <br />earlier, the objective was to discriminate among different drainage pat- <br />terns with respect to their hydraulic characteristics. Ideally, this <br />would incorporate factors of channel length, slope and cross-sectional <br />area, as well as the branching structure. However, the measurement of <br /> <br />all these elements would have involved an unreasonable amount of labor, <br /> <br />and therefore, attention has focused on the branching structure. <br /> <br /> <br />Networks have been coded by a method adapted from Smart (1970) and <br /> <br /> <br />other workers. The coding is based on the individual stream link which <br /> <br /> <br />is a channel segment bounded by junctions or sources. This enables the <br /> <br /> <br />drainage network to be represented by a vector of integers in which ex- <br /> <br /> <br />terior links or sources are distinguished from interior links. Instead <br /> <br /> <br />of a simple binary coding, however, the technique used here accounts <br /> <br /> <br />for the abundance of glacial ponds and their possible influence on the <br /> <br />. <br /> <br />. <br />