In the present case, where the sheets were so small, the row is much longer than necessary, so in the sheets it extends through the margins on all sides, as in [plate II].
The horizontal rows may be perforated first (one row at a time), and then the sheet is turned sideways and the vertical divisions are similarly perforated. A peculiarity of this style of perforating machine is that the points where the vertical lines cross the horizontal lines rarely fail to fall foul of each other, and an effect is produced like this—
Single line perforation. Note the crossing of perforated lines.
In this manner it is possible to tell blocks and pairs of this perforation without any side margins. Single copies perforated in this manner can occasionally be detected by the distance between the vertical perforations. In the later perforation of this issue the distance is fixed (as will be shewn), and the distance is 20½mm., measuring from perf. point to perf. point across the stamp. Any stamp differing in width to any extent more than ½mm. from 20½mm. may therefore be set down as perforated by the single line machine.
We have seen all the values except the 2d. rose and 1/- green perforated by the single line machine, in practically every case the C.C. watermark being upright, the exception being a strip of three 6d. with the sideways watermark. All the sheets with this perforation appear to have one printer's guide dot in the centre of each side margin.
The next form of perforating machine introduced in later printings of the Crown and C.C. 1880 issue is known as a comb machine. The comb machine perforates three sides of a stamp at once, and the form of the first comb machine was arranged thus—
The arrangement of the teeth of the comb fitted the arrangement of the panes of the regular Colonial postage stamps printed by Messrs. De la Rue & Co., the narrow spaced teeth in the centre marking the dividing space between two horizontal panes.