Together with a number of other colonial possessions, Gambia was admitted to the Universal Postal Union on January 1st, 1879, and in June of the following year (1880) a more comprehensive series of postage stamps was issued, all modelled after the same fashion as the two denominations which had done service in the Colony for the previous twelve years. The convenience of perforation was adopted at the same time. The new series comprised the following values, the shades being given in the approximate order of printings-- 1/2d. golden yellow, deep golden yellow, pale orange, vermilion, deep orange vermilion, citron,[1] pale ochre.[1] 1d. lake, deep lake. 2d. pale rose, rose, deep rose. 3d. pale ultramarine, deep ultramarine, deep blue. 4d. sepia brown, deep sepia brown. 6d. pale blue, blue, deep blue. 1s. bright green, deep green. [Footnote 1: The 1/2d. citron and 1/2d. pale ochre are generally believed to be changelings, due to atmospheric or other influences after the stamps were printed.] [page 26] [Illustration: Fig. D.] [Illustration: Fig. E.] The watermark on this issue appears variously upright or sideways, varieties of each being inverted. The normal "sideways" may be taken as from left to right. Portions of the marginal lettering and the vertical division lines of the panes are also to be found. The following is a synopsis of these varieties-- Crown C.C. vertical (Fig. A). " " inverted (Fig. C). " sideways (Fig. D). " " inverted (Fig. E). Portions of words "CROWN COLONIES." Division lines of the panes. The subject of perforations is of peculiar interest in this and the next issue of the stamps of Gambia, as while to a certain extent the printings are to be differentiated by shade the chief distinctions may be made in the case of blocks and sheets by the perforations. At first the stamps were perforated by a single line machine gauging 14. A single line machine, as its name implies, simply makes a single long row of holes in one direction-- ................................................................. 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. [page 29] 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-- [Illustration: Single line perforation. Note the crossing of perforated lines.]