This die appeared in March, 1854, and remained in existence until October, 1860. On account of its six years of constant use, it was not strange that the die should need repairing and retouching. Nevertheless, while admitting the necessity of repairs, this does not account in any way for the fact that we have thirty distinctly different dies in this series, many of which cannot be explained by the above theory. Of course, the various curves of the labels may be accounted for by repeated retouching, but no one who compares many of these dies would attempt to give the same reason for the totally different lettering and the great variety in the spacing. As a matter of fact, most of the so-called varieties are far more distinct dies than some of the well-known Reays and Plimptons of equal denominations. In spite of the great number of varieties of this issue, the engraver has seen fit to use but one head of Washington, which is totally different from any of those preceding. HEAD XV. [Illustration: XV.] Two fine, very short side-locks, reaching to the middle of the ear-lobe, which is rather large. There are seven very thin locks of hair, almost hair lines, in the upper part of the head, extending to the back of the head, each with a curve in the centre. Below these there is a short, thick bunch, or lock, bent upwards into the space left by the curve of the seventh thin lock. There is one short, thick front-lock and three in the back row, side by side, nearly at right angles to the bunch of hair which is bent upwards. The lowest front-lock slants a considerable distance across the ear, while the lock immediately above it is much longer and reaches into the queue. The latter is very thin and shows no subdivisions. Doubtless the thirty varieties of this die would have been highly prized by collectors and would have been well known many years ago if American philatelists had taken the trouble to study them with a view to systematic classification. Certainly, without a system the collector's task is troublesome, but, with a proper classification, the difficulty vanishes and what has hitherto been considered an annoyance becomes a pleasurable pursuit. This issue greatly favors the collector of cut square specimens, for a good many dies can easily be found. On the contrary, the collector of entires, especially the advanced collector who desires mint copies, will find it difficult to get unused specimens of many dies. The paper used is white and buff, and, as mentioned before, both the quality and color differ widely. For instance: "Buff" covers shades which would be called at the present time light chocolate, brown, oriental buff, light yellow, etc. A great many envelopes are of soft paper, nearly unsurfaced, while there are numerous others having a hard, brittle texture, highly surfaced or glazed. Often six shades may be obtained, and they are certainly worthy of being collected with care.