Sheet markings can sometimes make the difference bewtween an 'ordinary' collection and an 'interesting' one. They usually encompass blocks as opposed to singles and are therefore more eye-catching. They also give an insight into printing procedures and layouts and so add an extra dimension to a page. As with most stamp collecting areas, this is a large subject which cannot really be covered in one article so I have picked out the following, which I hope may be of interest.
Jubilee Line — Continuous rule
The Jubilee line was used to protect the stamp images from the initial impact of the printing rollers. Figure 1 shows the 1887 Jubilee issue. 4½d value, pane of 20 showing part of the word POSTAGE of the watermark on the bottom margin. The left hand side of the pane has the gutter with "Ladders" and the continuous rule (that is — the ruled line, around the whole pane, just outside the frames of the stamps is unbroken). Between this pane and the pane immediately below it were two rows of unprinted paper, and to stop their fraudulent use, horizontal ladders were printed across them.
Jubilee Line — Co-extensive rule
In the co-extensive rule, the jubilee line is broken at the perforations. This is illustrated here on the King Edward VII 1d value which shows a mock-up of a pair of panes, showing the inter-pane gutter with the vertical lined ladders and the marginal rule crossing the gutter at each end. This also illustrates the co-extensive rule, (the line broken at the perforations) FIG 2
These markings were used by the printers and were for accounting purposes. The use of controls was confined to the ½d and 1d values only for almost 20 years, the first major change being on early Edward VII issues, when a number, denoting the year of issue, was added. The first control thus affected was the letter C which was extended to the control C4
Sheets bearing controls A to J10 were printed by De La Rue and Co. And A11 by Harrison and Sons.
The reign of King George V. Saw further changes when the ordering authority, requested that the control letter and number be extended to sheets of all denominations up to, and including, 1/-.
The ½d value shows the control underneath the 2nd stamp, as do the others except the 1d.
The 1d value shows the control under the 11th stamp as in the EVII issues.
At this time printing was being done by both Harrison and Sons and the stamping department of the Board of Inland Revenue at Somerset House. The control is the only positive method of distinguishing the two printings. In the Somerset House printings the control letter is separated from the numerals by a full stop. The Harrison and Sons printings do not have the stop.
The change to Photogravure printing for the 1934 — 36, and subsequent issues, brought radical changes in the control. A few early printings had the control in the bottom sheet margin and it was then moved to the left margin. As side margins are very often narrow, the control had to be re-arranged. Whereas previously they appeared in line, they now appeared as an algebraic fraction — the letter being above the figures and with a bar between. Also at the same time an additional marking appeared. This was the cylinder number and it appeared below the control, in smaller type as illustrated in this halfpenny value of King Edward VIII.
Another variation appeared shortly after the re-arrangement of the control, which introduced bars below and round the fractional marking to denote the continued use of a given control instead of changing the control itself. In some cases this was recommenced a second time. Each bar shows a control period and the longest use of the boxing appears to be on the 7d value with control E over 39, in which the box was completed and a further two bars were added also. Figure 5 shows the penultimate state — full box plus 1 bar.
With the introduction of the decimal definitives, the cylinder numbers were boxed in — in the case of monochrome values a single boxed figure and in the multi-chrome values the first colour cylinder appeared in a box and the second colour below, and outside the box.
A phosphor cylinder number was introduced toward the end of the Machin Sterling issues, positioned in the bottom right hand corner. It was later transferred to the left hand side usually near the ink cylinder though there were examples of misplacement, sometimes considerable. Also there were examples of two phosphor cylinder numbers, large and small, on the same sheet. The phosphor cylinder number was extended to commemorative issues. Often the number was trimmed off. The phosphor number can be seen by holding up to the light and more easily with a phosphor lamp. Figure 6 shows the phosphor cylinder number on which I used a highlighter pen to make it visible. This is obviously not recommended for 'good' stamps and I used a common, low value definitive for the purpose
Peculiar to photogravure printings cylinder numbers denote the cylinder from which the sheet came. On double pane — reel fed printings, two types appear — stop and no stop, with the stop appearing beside the bottom of the figure. The no stop on the left on definitives may be reversed on commemoratives.
On monochrome stamps the cylinder number is a single numeral whilst on multi-chrome stamps it consists of a series of letters and figures. Each colour is printed on a separate cylinder, each one with its own number. Figure 7.
Booklets first appeared in 1904, and at that time, special plates of 20 rows of 12 were made with an interpane gutter between rows 10 and 11, but the Machin panes were printed on 21 row cylinders in continuous sheets, and show no stop and stop panes. On booklet panes the cylinder number was sometimes trimmed off during booklet make — up. Figure 8 illustrates the stop and no stop cylinders.
The Anniversaries issue, of 1969, saw the addition of a new sheet marking. In the side margins of the sheets, the words "Total Sheet Value", and the appropriate figure were shown. This was extended to include the definitives and it is found on sheets printed for booklets as well as the normal sheets. Figure 9.
NOTE:-The next three types were not illustrated in the original article on the web, but I have inserted the illustrations here for clarity.
These arrows appear in the middle of each of the four margins of all photogravure sheets. They can be shaped as a "V" or as a "W" and they can be either hand engraved or photo-etched.
Found on reel fed multi-chrome printings, these are 13mm. long bars, one for each colour. They were initially stippled and then photo-etched as solid bars. Sometimes duplicated they give a check, electronically, on the registration of colour during the printing.
These are shown as crosses or short bars, one for each colour of the printing. In the case of the 1966 World Cup Winners, the colours were also numbered and written in the right hand margin of the upper sheet.
click here for a larger image.
These identify the plate used for the printing. The Bradbury Wilkinson printings of the Castles series high values were printed in paired plates. The numbers were on the left pane and the 'A' numbers on the right pane. Figure 10
The Machin sheets were divided into four panes, each with its own plate number. The bottom left pane had the numeral only and the remaining ones had the numeral followed by the letter A B and C. Figure 11.
The variety of sheet markings has increased with the introduction of more printers of G.B. stamps, Questa, Walsall and Waddington for example, so anyone interested could amass quite a sizeable collection of G.B. Sheet Markings..
Sources:- Stanley Gibbons Specialised Catalogues Vols. 3 & 4.