6、今有东南望波口(AB),立两表(P和Q)南北相去九丈(d),以索薄地连之(如图六)。当北表(P)之西却行去表六丈(b),薄地(C)遥望波口南岸(A),入索北端 6. Today, there is the Southeastern Hope Point (AB), where the two tables (P and Q) go north and south to nine feet (d) and are connected to thin lines (see Figure 6). When the west of the North Table (P) goes to the west of the table (b), the thin land (C) looks to the south bank of the wave (A) and the north of the cable