Evolution of the Post Office stamp vending machines
As early as 1857 the possibilities of a coin-in-the-slot machine for the sale of stamps were attracting the attention of inventors, and a certain Mr. S. Denham applied for a provisional patent for a "Penny-in-the-Slot" machine, but nothing seems to have materialised from his invention.
In 1884 the Post Office erected a machine in Cannon Street Station, London. No information seems to exist regarding this machine.
No further moves were made by the Post Office until 1906 when serious experiments began. These led to the adoption of a particular machine known as the "Kermode" after its inventor. Another machine was tried out at the London Chief Office, from February to July 1907. This dispensed a 1d. stamp and also a 6d. packet of post cards on the insertion of the appropriate coin.
The first "Kermode" machines are believed to have been installed at the House of Commons B.O. and Threadneedle Street B.O. during the early part of 1907. A further 12 machines were installed by the Post Office between July 1907 and April 1909. The use of the machine was confined to London for a considerable time, but on the 21st and 22nd of March 1923, machines were installed at the High Street and Exchange Branch Offices in Birmingham. From then on installation of the machine spread throughout the country until by 1960 it had become one of the most commonplace in existence. With the extension of the use of this machine the name "Kermode" was dropped and it was henceforward known as the Post Office Vending Machine.
The latter is an intricate piece of mechanism that provided a very fine service with remarkably little trouble. The largest roll of stamps used by the Post Office contained 1,920 stamps and at certain busy offices this roll was replaced twice in one day, and yet it was a rare occurrence for a machine to break down or require more attention than periodical cleaning.
Types and Styles of Machine
1. Two machines, painted red and mounted on a black pedestal; one issuing a half-penny stamp and the other a 1d. stamp on the insertion of the appropriate coins. This is believed to be the oldest type of machine still in use.
2. One, two, or more machines set in walls of buildings, particularly Post Offices, were the next type to be installed. In 1960 these formed at least 80% of the Post Office Vending machines. They were generally in pairs, one issuing the half-penny stamp and the other the 1d. stamp on insertion of the appropriate coins. However if there was only one machine this usually issued two half-penny stamps on insertion of a 1d. coin. This type of machine, having the adjustment which allows it to issue two stamps, was known by the Post Office under reference "C4", while the type that issued one stamp, was known under reference "B4".
In 1951 a "3rd Value" was introduced: a machine which issued a tuppenny stamp on the insertion of two penny coins. The 2d. stamp, because of increases in the postal rates, was required for the Post Card rate and the new machines were installed at holiday resorts, hospitals and other places where a heavy card mail was usual.
In 1958 the "4th Value" was introduced: a machine which issued a 3d. stamp on the insertion of a 3d. piece. The 3d. stamp machine became necessary after the postal rate increases of October 1st 1957 when the minimum letter rate was raised to 3d. Work was started early in 1958 on the construction of a machine to take a 3d. piece, and by 15th May 1958 the first one was brought into use at London S.E.D.O. By mid 1959 one hundred of these machines were on field trials. (This is the machine fitted to our Crown Office bronze front plate in the Museum)
A quaint machine which comes in the "Built in a wall" group could be seen at Market Hall, Pembroke Dock, but is no longer in use. This, on insertion of a penny coin used to issue: "1d. postage stamp with paper and envelope", or a "stamped post card and a half-penny stamp". The rest of the notice on the machine reads, "Place a penny in the box and pull the handle until the bell rings". Later Postal Stationary Vending Machines are shown in PO Engineering notices from the early 1960s, but none is thought to have survived.
3. One machine on the side of a pillar box, dispensing two half-penny stamps on the insertion of a 1d. coin. It was unusual to see two machines in such a position, but when this did occur, one issued a half-penny and the other a 1d. stamp, until the elimination of the halfpenny in 1967 rendered these unserviceable and many were later converted for use with one New Penny coins, leading to pairs of SVMs vending penny (1p) stamps, such as at Theydon Bois in Essex, the last pair of extant machines and now in a private collection on the Herts & Essex border.
4. Machines recessed into a pillar box, making it an oval shape. (PB29 & 30) These are not often found but in the few cases known to exist they were all of the type that issue two half-penny stamps for a 1d. coin.
5. In the late 1950s a new practice of installing a large batch of automatic machines, all set in one grand frame, was introduced and it was announced in October 1959 that a large number of these suites of machines were on order for use both inside Post Offices, and on sites away from Post Offices. The first of these suites was installed at the South Eastern District Office, London, on 15th May 1957. This, at the time of installation, sold half-penny, 1d. and 2d. stamps, 1/- books, post cards and envelopes. (Later 2/- books, 2d., and 3d. stamps were added to the list of items for sale.) A second similar set was installed at the Kingsway B.O., London, a few months later. Additions to this suite in 1960 were a "Two three-penny bits for a sixpence piece" change machine, and 2/-, 2/6 and 5/- Postal Order issuing machines.
It should be noted that in all the machines so far mentioned, the stamp is projected automatically as the coin drops, but during the week ending 22nd of August 1959 two new machines were installed in the suite at the S.E.D.O., London. The first was a machine which issued a 3d. stamp after the insertion of three pennies OR a 3d. piece, in the slot and the pulling of a knob. The second machine issued a 2d. stamp (then the post card rate) after the insertion of two pennies and a half-penny in the appropriate places and the knob had been pulled. These two machines were removed by January 1960.
Any of the machines described here may have existed with small variations, and most would have been found with little metal plates attached to them. The wording on these plates may be any of the following or combinations of them:
(a) DAMAGED COINS MUST NOT BE USED.
(b) AWAIT DELIVERY OF STAMP BEFORE INSERTING A FURTHER COIN.
(c) TWO 1d. STAMPS FOR ONE PENNY.
(d) THIS MACHINE ISSUES A 2d. STAMP INSERT TWO PENNIES.
The Mechanism of the Standard Post Office Stamp Vending Machine
The insertion of a coin first lifts a coin plate, then, when pressed, the coin enters the machine lifting the "driving weight". This is connected to a rack and pinion, which ultimately drives the stamp feeding mechanism;
At this stage the coin falls on to the coin guide and rolls past the testing device for ''misformed and abnormal" coins. When the coin has been accepted by the machine, it falls into a chute and thence to a balance arm. This acts as another testing device, as it only operates if the coin is the correct weight. This arm on being fully operated allows the escapement mechanism to rotate and permit the "driving weight", lifted when the coin entered, to draw the feed wheel sufficiently to feed one stamp through to the stamp aperture. Unaccepted coins are rejected and can be picked up in the cup below the stamp aperture.
The roll of stamps is placed on a spindle and held there by a metal arm. The stamps are then fed under a fixed guide bar, over a second guide bar and then under a bar which is pivoted to a lever. When the roll is finished this lever drops causing the "EMPTY" or in later years, "NOT IN USE" plate to drop over the coin hole. The stamps are now fed over a drum containing fixed pins, spaced at a distance of a stamp and fixed into the horizontal perforations, and at every fourth perforation at each side.
The stamp roll and dispensing mechanism are enclosed in a cork lined metal cover. (Not on all machines Ed) Fixed to this, near to the roll of stamps, is a dehydrator containing cobalt chloride crystals in a perforated container, the action of which is to absorb dampness from the atmosphere. When the crystals are dry they are a blue colour, but when they have absorbed their maximum amount of moisture they are pink. They can be dried out in an oven and used again.
The last style of machines have a lever which allows the "Not in use" plate to drop if the roll should break or the machine jam for any reason. Earlier-machines did not have this and the local Postmaster had to insert the plate.
Vending Machine Testing: the labels used
When setting up, adjusting and testing the automatic vending machines, Post Office Engineers made use of rolls of dummy stamps (Labels). There were numerous different types of these dummy stamps produced between about 1910 and 1935, for both Post Office machines and private ones. The main groups are: (all are perforated)
(a) Plain or coloured paper, with or without watermark, gummed or ungummed.
(b) As last but containing some design such as the Head of Thomas Richard Harrison instead of plain paper.
(c) The "Poached Egg" type issued by the Post Office in 1935/6. These were perforated 14 x 15. watermarked multiple "GVR and Crown" and gummed. Examples of this label are known postally used, having served as a half-penny stamp through the mail. It has been suggested that after testing a machine, a dummy roll was left in by accident, so that the dummies were then vended and used as stamps.
(d) White paper with a thin green frame line and green saltire. Unwatermarked but gummed,
(e) Green paper with a white, gummed back. Watermarked "Harrison & Sons Ltd., London" in script.
(f) Plain white paper, unwatermarked, gummed and perforated.
(g) Plain white paper, watermark Multiple GviR & Crown, gummed and perforated.
(h) For Testing Purposes only stamps, issue in 1938, watermarked (various reigns) gummed and perforated
(i) With the advent of the Type F booklet dispensing machine, the For Testing Purposes Only stamps were issued in folded booklets containing a pane of four stamps.
The rest of the booklet is then devoted to a detailed listing of the various rolls that were issued.