PERCÉ EN SCIE is somewhat similar to PERCÉ EN POINTE, except that the slits are smaller and are cut in uneven zigzag (alternately long and short), so that the edge of a severed stamp is like that of a fine saw. PERCÉ EN SERPENTIN occurs when the paper is cut in comparatively large wavy curves of varying depth, with little breaks in the cutting which serve to hold the stamps together. And _see_ PERFORATED and PERFORATION. PERFORATED--in French PIQUÉ. This word implies removal of small discs of paper, not simply slits or cuts. And _see_ PERCÉ. PERFORATION is either "regular," where the number of holes within a similar space is constant along the entire row; or, where the number varies more or less, "irregular." The gauge of the perforations (or roulettes) of a stamp is measured by a PERFORATION-GAUGE, a piece of metal, card, or celluloid, on which is engraved or printed a long series of rows of dots, each row being two centimetres in length and containing a varying number of dots from, say, 6 to 17 or 18. A stamp, the edge of which shows holes (perforated) corresponding in spacing and number to the row on the gauge marked, say "12," is said to be "perforated 12." If the stamp gauges the same on all four sides, it is simply "perforated ..."; if the top and bottom are of one gauge, say 12, and the sides, say, 14, the stamp would be perforated "12 × 14." If the gauge varies on each of the four sides--an unlikely combination--then the order of noting same is, top (say 12), right (say 11), bottom (say 13), and left (say 15)--"perforated 12 × 11 × 13 × 15." In the above the gauges are supposed to be regular. [Illustration: PERFORATION GAUGE.] Should, however, the gauge be irregular, the extremes are noted even if not showing on the stamp: for instance, a stamp may be perforated with a machine, which, in its entire length, gradually varies from 12 to 16 holes in the two centimetres, though the stamp itself does not show all those gauges. Such a stamp would be "perforated 12 to 16." On the other hand, a row of perforations, instead of gradually altering in gauge, may do so abruptly; for instance, along a row of holes, part may gauge 14, the next part 16, and then 16½, all quite distinct over a particular space. This would be termed "perforated 14, 16, 16½," implying that the intermediate gauges did not exist. The use of a regular machine, in conjunction with one of irregular gauge, might produce, say, "perforated 14" (horizontally) "× 12 to 15" (vertically); and so on.