the knots 9a 9b thus formed are slid onto the needles 1a 1b respectively as illustrated in fig1 c in the weaving operation the first surface yarn 10a is looped or wound counterclockwise around the first needle 1a and interlocked with the second surface yarn 10b as illustrated in fig1 d and 1e then the second yarn 10b is looped or wound counterclockwise around the second needle 1b and interlocked with the first yarn 10a as illustrated in fig if to continue weaving the first and second surface yarns 10a 10b are alternately looped around the needles 1a 1b in the same manner as described as illustrated in fig1 g as a result a first two columned strip part 10 is obtained which includes left and right columns 11 12 each having a desired number of loops of the surface yarns 10a 10b respectively more particularly the first surface yarn 10a is formed into a first series of loops 11a disposed about the first needle 1a and each of the first series loops 11a is interlocked with and closed by the second surface yarn 10b at 12a as illustrated in fig1 g after the first pair of surface yarns 10a 10b are needlewoven into the first two columned strip part 10 the part 10 is slid down onto the hanging core yarns 2 while a second pair of surface yarns 20a 20b are needlewoven into a second two columned strip part 20 having a left and a right columns 21 22 in the same manner as illustrated in fig1 i when both of the strip parts 10 and 20 are slid down onto the core.