Identifying #55
A - On #63 the numerals in the upper corners arabesque ornaments extend downward and also across the top resting upon the curved frame line of the stamp.

B - On #63 the extreme tip of the upper left hand ornament is directly above the p of postage. In the August Issue this tip rests upon the curved line but does not extend below it. On #63 there is a strong dash under the tip and below the line.

C - On #63 there are shading lines under the upper ornament on the right.

D - On #63 the vertical shadings in the corner spaces which enclose the numerals and the letters u and s are increased.

The paper of the premieres gravures is very thin hard and extremely brittle. The stamps are easily cracked unless handled very carefully. The paper is also quite transparent and much of the designs may be seen from the backs of the stamps.

The gum is very dark brown sometimes staining the paper.

The Story Behind the Stamp
Often called the "Premiere Gravures" or "August Issues. Most philatelists now classify Scott #55–#62 as trial printings or samples (essays) rather than regularly issued stamps.

Of the 26 surviving stamps, three are cancelled, probably an experimental or control cancel applied at the Bureau