Letterpress — how the issue was printed
Everything that makes this issue interesting to a specialist — seven plates, a hundred distinguishable fields on each of them, types, plate varieties, white spots, doubled print — follows from a single circumstance: the stamps were printed by letterpress, on machines never built for work of such precision. This page explains how letterpress works, what goes wrong in it, and why that is a gift to the collector rather than a nuisance.
Relief printing
Letterpress prints from the raised surface. The printing elements of the forme stand proud, everything else is sunk. An inking roller passes over the forme and ink clings only to the tops; the paper is then pressed onto the forme and the image transfers. The sunken parts never touch the paper — and so stay white.
Two traces follow from that, by which letterpress can be recognised even after a century. The paper is indented where the printing elements met it — the design can be felt from the back and seen in raking light. And because the ink is squeezed outwards under pressure, it tends to gather into a darker rim along the edges of the inked areas.
Other techniques behave the other way round. In intaglio (line engraving) the ink lies in the recesses of the plate and stands up from the paper as a relief. In offset and lithography the plate is flat, the paper is not deformed at all and the print is smooth. A stamp said to be from this issue that shows no relief at all therefore deserves a second look.
From the drawing to the sheet
Mucha's drawing first had to be turned into a printing relief. From the finished element a printing forme of one hundred stamp fields was assembled — a hundred individual images side by side, not one image a hundred times over. This is where the whole of today's specialisation begins: whatever differs among those hundred elements differs always, and in the same place.
From this comes the division that runs through the whole site. A deviation tied to a particular stamp field is a plate variety — it recurs on every sheet from that plate and serves to identify both position and plate; these are the subject of the position gallery and the plate reconstructions. A deviation tied to one particular sheet or one pass through the machine is a production flaw — random, non-recurring, and belonging among the production flaws.
The rest of the process matters as much as the printing itself. The paper was dampened before printing so that it would take the ink, and perforating came last of all, as a separate operation on a different machine — on sheets that had dried in the meantime and could no longer be matched up with the printing. Each of those steps has its own group of flaws to answer for.
What goes wrong
An overview of the deviations by the stage of production at which they arise. The links lead to where each of them is treated in detail, with specimens.
| Stage | What goes wrong | Where on the site |
|---|---|---|
| The forme — wear and cleaning | Damage to a printing element: cracks, broken pieces, retouches. Tied to a stamp field, developing over time. | Damage to the printing plate |
| Inking the forme | Too little ink, or a clogged recess — weakened or missing print (white spots). Too much ink — blurred print and smears. | White spots · Printing flaws |
| Dampening the paper | A soft sheet ripples and gathers; no ink reaches the fold and the design fails to meet. | Creased paper |
| The impression | A foreign object under the sheet lifts part of the surface — part of the impression comes out smeared or doubled, with a straight boundary. | Partly doubled print |
| Perforations | Hand feeding and dozens of separate strikes: shift against the design, a double strike, a row left out. | Perforations · Perforation flaws |
Most of these deviations would count as spoilage today and the sheet would never reach the public. In 1919 printing went on under makeshift conditions, in haste and with whatever was at hand — and finished sheets went to the counters as they came out. That is why so much material survives that it can be studied statistically, not merely as isolated rarities.
Why this is an advantage for the collector
- Every stamp carries an address. Because the forme was made up of a hundred separate elements, each field has a small identity of its own. On an ordinary modern stamp nothing can be established; here a single copy can be assigned to a plate and to a stamp field — and a whole sheet reassembled from such copies.
- Flaws develop, and so they measure time. A crack grows, a white spot deepens. Arrange copies by the state of the flaw and a chronology of the printing appears, one that can be checked against the dates on the cancellations — and used to date copies that carry no date at all.
- Random flaws make unique pieces. A crease, a doubled impression or a missing perforation arose in one particular pass of the machine. Such a copy is literally one of a kind, and yet costs a fraction of what a “classic” rarity does.
- The relief is a test of genuineness that costs nothing. Letterpress indents the paper. A forgery made by offset or by a present-day printer is smooth, and in raking light that shows without any instrument at all.
- Study is not a question of budget. The 15h is a common stamp that can be acquired by the hundred. Depth of knowledge here does not depend on what one spends, but on how much material passes through one's hands and how carefully it is recorded.
Recognising letterpress on the stamp in your hand
- Relief from the back. Turn the stamp face down and tilt it towards a point light. The design appears as fine raised areas; the frame and the lettering of the inscription read best.
- The rim of ink. Under a glass, the ink along the edges of solid areas is darker than in the middle. It is the trace of ink squeezed sideways under the impression.
- The whites are truly white. The unprinted areas are bare paper, not a lighter shade of the ink. The ink lies on the surface and, where the impression is strong, can be felt from the face as well.
Two reservations. The relief can be flattened — on copies that have been soaked, washed or pressed in an album it may be barely perceptible, so its absence proves nothing by itself. And conversely: the relief is an indication, not a certificate. Where the identification really matters, it cannot take the place of one.