Introduction
The intention of this section of the Encyclopaedia is to examine the production of postage stamps by
Harrison & Sons for the Post Office from the commissioning of designs to the delivery of the stamps for
sale. Background knowledge of stamp production will assist in understanding how the many varieties found
can be explained, as well as, hopefully, reducing the number of inadequate or incorrect descriptions
attributed to variations. In addition we shall be examining the variety of papers, gums and perforations
used, as well as how stamp booklets and coils were produced.
Following the breakup of the Federation of Rhodesia & Nyasaland, each of the three constituent territories
regained control of their postal services and issuing of stamps. Harrison & Sons, who had printed the
commemorative stamp issues of the Federation, was responsible for the printing of all territories’ definitive
issues. Northern Rhodesia was the first to issue a definitive set, of the state’s shield from its armorial coat
of arms on 10th December, 1963. Nyasaland first overprinted surplus revenue stamps, and then issued a
pictorial set on 1st January 1964.
Southern Rhodesia was the last to issue its new definitive on 19th February 1964, this definitive was also
the last to bear the name of “Southern Rhodesia”. With Zambia becoming independent on 24th October
1964, the Government dropped the “Southern” and the territory became known simply as “Rhodesia”,
although legally in international terms this was incorrect. Harrison & Sons were to be responsible for
printing of three commemorative issues and an additional definitive in 1966, all of which bore the name as
“Rhodesia”.
With the Unilateral Declaration of Independence by the Rhodesian Government in November 1965 and the
imposition of trade sanctions by the British Government, Harrison & Sons lost the Rhodesian printing
contract.
Outline history of Harrison & Sons
Harrison and Sons Limited was a major worldwide engraver and printer of postage stamps and banknotes.
The company was established in 1750 by Thomas Harrison; in 1839 Thomas Richard Harrison entered into
partnership with John William Parker, creating Harrison and Co. It went through similar names and retained
a link with the Harrison family until 1979 when Richard Harrison left the company.[1]
It obtained its first British Post Office contract in 1881. The company won the contract to print the single
colour United Kingdom Edward VII stamps in 1911 after the Post Office decided not to renew its contract
with De La Rue. Initially, using printing machines manufactured by Timsons of Kettering it went on to
produce most of the British stamps over the 60-year period from the 1930s until the 1990s, including the
first UK stamp using the photogravure method in 1934 and the first photogravure commemoratives in 1935
for the Silver Jubilee of King George V. The first UK Christmas issue in 1966, on the specially designed
Jumelle press, was also printed at Harrison and Sons. They printed their last British commemorative issue,
referred to as ‘Queen’s Beasts’ issue, in 1998. The stamps were actually printed one year before they were
issued to the public.
The company (abbreviation H&S) also printed stamps, banknotes, passports and gift vouchers for over 100
other countries from 1881 until 1997 when it was acquired by De La Rue security printers. Some of its most
famous publications were The London Gazette and Burke's Peerage. In addition to union related issues at
Harrisons, rumours suggested that the sale was also prompted by the steady inroads being made by
Harrisons into De La Rue's banknote business.1
The first stamps printed by Harrisons for the Federation were the 3d and 6d values of the Kariba Dam issue
in 1960, thereafter the company printed the remaining Federal commemorative issues. All three constituent
countries retained the services of Harrison & Sons for a few years after the Federation’s breakup.
The initial stages
The decision to issue stamps was taken by the Ministry of Posts, which commissioned Harrison & Sons to
produce the stamps using its in-house artist Victor Whiteley. All post-Federation stamps printed by
Harrison & Sons were designed by this artist, using photographs and other materials provided by the
Ministry. However, although sometimes attributed to Victor Whiteley, the 1965 Churchill issue was the
work another in-house artist T E “Harry” Baxter.2 There appears to have been communication between
Harrison and the Ministry on the final designs, colour and number of plates to be used for each stamp.
Photogravure printing
All Harrison & Sons issues were printed by the photogravure process. The term “photogravure” comprises
two elements, firstly that the image is produced by various photographic processes. “Gravure” is a process
whereby the image is etched onto plates, this is the characteristic of all intaglio, or recess printed processes,
in the photogravure process the etching is done using photographic means.
On approval of the artwork by the Ministry, the next decision was the number of colours each denomination
in the issue was to be printed in. During this period the standard print colours of cyan, magenta, yellow and
black (CMYK) were not in common usage. The greater the number of colours used in the printing of the
stamp, the greater the cost of production due to the number of printing plates that were needed. For example
in the 1964 definitive five of the stamps were printed in two colours (2d, 3d, 4d, 9d & 1/3), seven in three
colours and two in four colours (10/- & £1).
Having decided what colours were to be used in the printing, the artwork was then photographed and
through the use of negative images and various filters the elements of the artwork were separated.
In addition it needed to be decided how solid the ink colour
needed to be, which dictated the extent of the screening
necessary. In the example shown here of the 1966 9d
definitive the background colour was to be solid, which
required a dense screen. For the Queen’s cameo however there
was a need for a finer screen to enable the facial features to be
clearly seen whilst still using one colour ink. The tobacco
leaves however also needed to have a fine screen so that the
detail of the leaf with the veins and outlines printed in the same
violet ink of the background.
In other stamps of the two definitive issues there was the need to use a fine screen, probably 300 dpi, over
whole artwork, so that the finer details of the illustration could be captured. The photographing of the
artwork to separate the colours may need to be undertaken several times. Once the artwork had been
separated, there was the need then to introduce a uniform format for the Queen’s portrait and text required
for the stamp – country name, value, description and other text. This would probably be been developed
separately to the main artwork, and then photographed separately, finally coming together with the
photographed artwork for the relevant colour. Whereupon it was re-photographed together as positives or
negatives. Once any adjustments were made of the final product it was now necessary to replicate the
individual design for each colour by the number of stamps required in the printed sheet. Again this was
undertaken by photographic means. Finally the marginal notations and printers guidelines would need to
be added around the sheet of stamps.
Printing plates
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The manufacture of the printing plate is a long and involved process. Below is a detailed description of the
process of manufacturing the photogravure plates go through several distinct stages:1
First, film positive is made through the process just described.
The second stage is to sensitize a sheet of pigmented gelatin tissue by immersion into a 3.5% solution
of potassium dichromate for 3 minutes. Once dried against a Plexiglas (Perspex) surface, it is ready for
the next stage.
The third stage (usually the next day) is to expose the film positive to the sensitized gravure tissue. The
positive is placed on top of the sensitized sheet of pigmented gelatin tissue. The sandwich is then
exposed to ultraviolet (UV) light. A separate exposure to a very fine stochastic or hard-
dot mezzotint screen is made, or alternatively an aquatint grain of asphaltum or rosin is applied and
fused to the copperplate usually before the exposed gelatin tissue is adhered to the plate. The UV light
travels through the positive and screen (if used) in succession, each time hardening the gelatin in
proportion to the degree of light exposed to it.
The fourth stage is to adhere the exposed tissue to the copper plate. The gelatin tissue is adhered or
"laid down" onto the highly polished copper plate under a layer of cool water. It is squeezed into place
and the excess water is wiped clear.
Once adhered, the fifth stage is to use a hot water bath to remove the paper backing and to wash away
the softer, unexposed gelatin. The remaining depth of hardened gelatin is relative to the exposure. This
layer of hardened gelatin forms a contoured resist on the copper plate. The resist is dried, and the edges
and back of the copper are stopped out (staged).
The sixth stage is to etch the plate in a series of ferric chloride baths, from the densest to slightly more
dilute, in steps. The density of these baths is measured in degrees Baumé. The ferric chloride migrates
through the gelatin, etching the shadows and blacks under the thinnest areas first. The etching
progresses through the tonal scale from dark to light as the plate is moved to successively more dilute
baths of ferric chloride. The image is etched onto the copperplate by the ferric chloride, creating a
gravure plate with tiny "wells" of varying depth to hold ink. The pattern formed by the aquatint grain
or the screen exposure creates minute "lands" around which the etching occurs, giving the copperplate
the tooth to hold ink. The "wells" which hold the ink vary in depth, a unique aspect of photogravure.
The final stage is to print the cleaned plate.
Printing press
The actual printing press comprises a series of individual units, each of which prints a different colour as
the paper is fed through the press.
A unit of the printing press comprises two
cylinders, the first being the plate cylinder onto
which the printing plate is attached. This cylinder
is placed within a trough of ink, which becomes
embedded in the etched areas of the plate. As the
cylinder spins round in a clockwise direction it
picks up the ink, any excess is then scrapped off
by the doctor blade, before it reaches the paper
being fed through the present. The second
cylinder is known as the impression cylinder,
which acts as a support for the paper to take the
ink from the plate to give the printed image.
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The single unit of the printing press is one of several units linked together to give a continuous print run. Below
is a diagram of a seven unit press, which is more common today than it may have been in the 1960’s. By having
several colours in a print run, the quality of the printing can be improved considerably.
Number of printing plates
In general all the issues had a single printing plate or cylinder for each colour, these are all notated as “1A”,
however some of the middle values of both the 1964 & 1966 definitive issues had an additional cylinder –
“1B”. The cylinder 1B values for the 1964 issue were for the 6d, 8d and 1s3d values. The Rhodesia Stamp
Catalogue states on the 1966 definitive “part of the printing was sent to Rhodesia and part retained in
London owing to sanctions. All sheets of all values had cyl. nos., but it is uncertain which values had both
A & B cyl. nos.”3 The Mashonaland Guide however states that only the 6d, 1s, 1s6d and 2s6d were issued
with cylinder 1B values, no evidence has come to light of there being any other.4
Papers and Gums
The paper and gums were consistent throughout this period, being described as “white unwatermarked
paper. Colourless gum” by the Mashonaland Guide, 4 and in the Rhodesia Stamp Catalogue as “Paper:
white clear gum”.3 There is however a known un-catalogued variety of paper and gum for the 1965 ITU
issue, where it is off white non-fluorescent paper with a cream gum.
Marginal Notations
All sheets have
the printer’s imprint below the two centre stamps in the bottom margin, reading “Harrison and Sons
Ltd London”. The colour of the imprint being one of the printing colours.
The cylinder number below the second from the right stamp in bottom margin, and shows each of
the printing plates in the colour of that plate
The sheet values are printed in £.s.d. above the far top right stamp in the top margin, the amount
stated is a multiplication of the stamp value by the number of stamps in the sheet. The sheet value
is printed in one of the printing colours, usually the same colour as for the printer’s imprint.
Colour registers: there was no colour register to the sheets of stamps for the 1964 definitive, they
however appeared on all subsequent issues. The printing colours of all the cylinders were in
rectangular format with a box. However as the colour registers are seen on the very edge of the
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printed it appears that the rectangular shape and the box are cut in half. The width the colour register
is variable.
Sheet number: These are printed separately and generally occur in the top left sheet corner to the
left of the far left stamp.
Printer’s guidelines: occasionally one or more of the margins have a line or series of lines near the
edge of the sheet. These would normally be cut off the printed sheet. Only noted, so far, with the
1964 definitive issue.
COILS
Both the 1964 and 1966 definitive issues had coil stamps produced. The coils were produced from the
printed sheets of 240 stamps (10 rows by 12 columns). The makeup of the coils were described by the
Mashonaland Guide, 3 as follows:
“The sheets are split in half forming a sheet 12 x 10 and are joined according to the way in which the
stamp is required for the roll. In this case they are joined side by side so that they form a complete length
10 stamps deep and are then split into coils. It is normal custom to keep each half separately when joining,
therefore, the flaw on the fifth stamp (1d) in Row 1 would only appear once in every 20 coils. Should,
however, the bottom half be joined on the top half, then the flaw would appear once in every ten coils. If
10 coils from the same reel were inspected, the flaw would be found to occur in either one, or twenty, as
mentioned and this would become the 5th, 17th and every 12th stamp thereafter. (This information was
supplied by the courtesy of Messrs. Harrison & Sons, Ltd., and the Postmaster-General, Salisbury).”
Coils were produced for the ½d and 1d values for the 1964 definitive and 1d value in 1966. As the stamps
are produced from the printed sheets, the stamps cannot be distinguished from those sold from the sheets
of stamps. Indeed the Rhodesia Stamp Catalogue does not list the coil stamps. However they can be
identified as being from coil sheets if the join between the two strips of stamps can be identified.
The example above is a strip of 5 coil stamps. The join in the coil is between the two far right stamps.
But what makes this more interesting is that the perforating of the far right stamps has shifted
downwards, thus clearly identifying this as a coil. The back of the stamp, below, shows the join in the
coil in the same position (the stamps are inverted)
BOOKLETS
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Harrison also produced booklets for the 3d values in booklets of one shilling, a single block of 4 stamps all
of which have a margin to the left in the stitched booklet. The Mashonaland Guide describes the production
of the booklets as follows. 3
“Printed in four columns of twenty giving a sheet total of 80 stamps. Each column contains ten horizontal
or ten vertical pairs. After printing and perforating, the component parts of the booklets are assembled in
layers which are stitched one at a time. For cutting, the layers are stacked in piles twenty deep producing
400 booklets at a time. (By courtesy of Messrs. Harrison & Sons, Ltd.)
These stamps have their own flaws which differ from the flaws found on the sheet stamps but it is not
possible to 'place' them because when the booklets are prepared for dispatch they are made up into packets
of 20 which may come from different piles.”
A 1964 booklet pane, note the stitch marks
along the left margin. The pane has been
poorly cut, appearing imperforate to the top
but with the full perforation to the bottom
The 1966 booklet, glassine leaves placed
behind the booklet pane to prevent it
sticking to the cover.
PRINTING VARIATIONS
Missing colours
As the stamps are printed in a continuous flow through the printing presses it is unlikely that a sheet of
stamps would be missing a colour in its entirety. However, there are the varieties known to have occurred
by what is referred to as a “dry print”. “This can be caused by two events on the printing press. The ink
trough runs out of ink, and streaks first to appear, as there is not enough ink to fill the recesses/cells. Or
the Press has been stopped for a time. The solvent dries out in the recesses/cells, clogging them up. When
the press starts again, it take time for the solvent in the trough to clear/dissolve the ink in the cells. Most
of these start up sheets are destroyed, but some slip through the checkers”5
Opposite, are two stamps from the 1966
definitive, the left with the missing blue and
the right with the missing brown printings.6
Below is a strip of stamps from sheet of 1s3d
stamps of the 1966 definitive, where part or
the whole of the central stamps are missing
the yellow-ochre colour. 6
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Plate movements
One of the most common errors found in photogravure printed stamps are plate movements. There are two
probable causes to this type of error, firstly that one the printing plates moved during the printing process.
This is unlikely reason as the plates are fixed in to the printing cylinder. The second reason, and more likely
cause, is that there has been some movement of the paper as it progresses through the printing press. Below
are examples of some of the more extreme movements found.
Printing Plate Varieties or Flaws
Many more specialised catalogues list flaws found in the stamps, these are varieties that occur on individual
stamps within the printed sheets. The listings of these flaws in catalogues such as the Rhodesia Stamp
Catalogue under many issues are faults that occur on all sheets of that stamp in a specific location. These
flaws are generally visible to the naked eye and as a consequence are easy to identify. These flaws are
known as constant varieties or flaws.
The Mashonaland Guide on the other hand also lists many minor spots, specks, blemishes and lines that are
not quite so easy to see with the naked eye. Whilst spots, specks, blemishes and lines are relevant to
someone collecting in such detail, they do not add significant value, if any, to the stamp. There are, however,
some constant flaws that are visible to the naked eye that are not listed in the Rhodesia Stamp Catalogue.
Below is an example of the 1964 3d definitive stamp where only one flaw is listed in the Rhodesia Stamp
Catalogue, with other visible flaws listed in the Mashonaland Guide.
Broken Oval,
booklet stamp.
RSC & Mash
ear. R19/1. Mash
Guide
As each issue is examined these flaws will be looked at in more depth.
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Non Plate flaws
Varieties or flaws that occur in some issues which do not appear on the printing plates are known as “batch”
flaws, as these occur in one or a few of the sheets of stamps. As these flaws only occur in batches they are
rarely catalogued, but do constitute additional interest for many specialised collectors. There are a number
of batch flaws that could be termed “standard” as they occur with some frequency in some issues, some are
however rarer. The following is a description of some of those varieties that frequently occur.
Doctor Blade flaws
This batch variety is particular to the printing of stamps by the photogravure process. When a piece of
foreign material gets caught by the doctor blade in a single unit of the printing press, or if the doctor blade
is damaged, the ink gets under the doctor blade and leaves lines of ink on the surface of the plate cylinder.
This then gets passed through to the paper, and is usually seen as a white line with thick lines of the ink on
either side. The doctor blade flaws are seen either perfectly horizontal or perpendicular to the bottom of the
stamp, the direction being dependent on the format of the printing plate to the direction of travel of the
paper. So stamps printed “the right way up” will have the doctor blade flaw horizontally, whilst stamps
printed on their side will have vertical doctor blade flaws. No individual stamp will have the doctor blade
flaw in both directions.
Other batch flaws
Numerous other batch flaws are found on stamps printed by the photogravure process, these include ink
blobs, smudges, additional line (not doctor blade), dots etc. These will be dealt with in more detail, if
relevant, when each issue is examined.
Printing Offsets
The last printing variations or flaws relates to
printing on the gum side of the stamp where all or
some of the printing inks can be seen. The probable
cause of this is that ink has not dried sufficiently
before the next printed sheet is placed on top. The
offset is a mirror image of the face of the stamp,
more often than not this is usually one of the
printing colours. In photogravure printing this is
relatively rare.
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PERFORATIONS
All stamps produced by Harrison & Sons for the period in question were perforated using the comb
perforation method. (For more detail on comb perforation see the section on the local printing of
Rhodesian/Zimbabwean stamp)
Stamp formats
The shape and size of each stamp produced is largely dictated by the comb perforators held by the printers,
in the case of the stamps produced by Harrison & Sons for Rhodesia five different comb perforators where
utilised.
Different catalogues show differences in the perforation gauges. Stanley Gibbons measure the perforations
to the nearest half unit, whilst the Rhodesia Stamp Catalogue measures to the nearest quarter. For example
Stanley Gibbons gives the three commemorative issues with a gauge of 14½, whilst the RSC gives 14¼.
For the analysis below the Rhodesia Stamp Catalogue measurements are used.
Also described below is the number of perforation holes making
up the comb that determines the stamp size. The number of
pinholes making the head are from, and including, the holes
between the two vertical teeth. The number of teeth holes are
those between two sets if head perforations. See illustration.
T o
o th
c o
u n
1 Low value
Perf gauge: 14½
2 Low value
Perf gauge: 14½
Perf holes: head 18: tooth 17
Note: the perforation of the low value defintives appear to have two comb perforators. Format 1
comb moves from one of the side margins, whilst comb 2 moves between top and bottom margins.
3 Middle value 1964
4 High value
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Perf gauge: 14¼
PERFORATING VARIATIONS
As with the printing of the sheet stamps there are a fair number of errors that occurred during the perforating
process.
Missing perforation strikes
No record has been found of full or partial imperforate stamps, but that does not mean that they do not exist.
Additional strikes
There are a number of examples of additional strikes recorded, these are usually through the margins of the
sheets. These additional strikes are usually through the sheet margin that should be imperforate, which
means that the additional strike happened before the full perforation of the sheet occurred. In addition the
strikes do not line up with the main perforations of the sheet.
Paper shifts
This variation is not that common but is known to occur.
The most striking example is with the 1964 1s3d
definitive stamp. This is incorrectly described in the
Rhodesia Stamp Catalogue as “Perforations down the
centre of stamp”. Unfortunately whoever obtained the
sheet of these stamps decided to cut out the stamps though
the stamp margins instead of separating them through the
perforations
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So far only one instance has been recorded of a
missing perforation hole. This is in respect of the
second tooth pin up between the 1st and 2nd
column. This variation does not occur in all sheets,
so this must have only occurred for short run of
stamps
penetrate through the sheet, but does leave an
indentation or “bruising” of the paper.
Note the printer’s guidelines to the far left of this
block.
printings of perforation errors to the corners of
some sheets. Strictly speaking it is not a
perforation error, as the perforator could not have
produced the variation. The reason for this
happening was that the corner of the sheet of stamp
had folded down, resulting in the margins being
perforated through. The variation becomes
apparent when the corner is unfolded.
FIRST DAY COVERS
The Ministry of Posts, through the Post Office, did not publish first day covers until the release of the 1965 Churchill
commemoration. All first covers produced for the 1964 definitive, 1965 ITU and 1965 Water Conservation issues
were privately produced.
The first day covers produced by the Post Office for the 1965 Churchill and 1966 definitive were, to be frank, rather
boring depicting the Rhodesian Coat of Arms. Private issues continued for these releases.
Bibliography
1. Wikipedia, free encyclopaedia, on the subject of “Harrison & Sons”.
2. Gibbons Stamp Monthly, “An Issue is Born: Rhodesia: Churchill 1965”, December 1965 - pages 61-3
3. The Rhodesia Stamp Catalogue, 1983/4, published by the Salisbury Stamp Company (last edition)
4. “A Guide to the Postage Stamps of Rhodesia, 1st January, 1964 – 31st July, 1966” published by the Mashonaland
Philatelic Study Group, supplement No 2.