we have used the expression for the Drude conductivity with the 2D density of states. The ratio of the weak localization correction to the Drude conductivity is of order for 2D weak localization and of order for 1D weak localization. In the 2D case, the correction is small , but still much larger than in a typical metal. The correction is greatly enhanced in the 1D case. This is evident in the experimental curves in Fig. 13, in which the resistivity increase at low temperatures is clearly visible only in the narrowest channel.