The earliest shape of the postage stamp is practically that which is in use to-day. The tri angular, diamond-shaped, octagonal, and square have been tried as experiments by different coun tries, hut in nearly all cases the return has been made to the rectangular form, and usually to about the same size as that of the original issue of Great Britain. Sizes have differed very greatly, the smallest, a stamp of Bolivar, a State of the Colombian Republic, being three-eighths by one half inch, and the largest the United States newspaper stamp of 1865, 24 X 37 inches.
The original designs of the stamps of many countries are their finest; but there arc notable cases in which the improvement both in design and workmanship has been remarkable. 'A prominent example of this is found in the various issues for Uruguay. The earliest types, those of 1856 66, are of the most inferior workmanship, and the stamps are produced by the cheapest processes known. Stamps of the next decade show some im provement, while those of the following years contain some of the finest work of the period, and also a num ber of specimens of poor work. The stamps since 1884. however, have been the finest possible examples that could be turned out under modern processes of engraving, and reveal from year to year the advances that have been made.
The methods of manufacture have changed very greatly since postage stamps were first issued. The earliest stamps, in several countries, were each engraved separately by hand, upon copper plates from which the impressions were taken. .k. notable example of this is the postmasters' stamps issued in Saint Louis. This small plate of six stamps was engraved in two vertical rows of three stamps each, the first row of the 5-cent and the second row of the 10-cent denomination. The two upper 5-cent stamps were altered to 20-cent stamps and later these were changed back to their original 5-cent de nomination. Separate engrav ing was also employed in the cases of the early stamps of Mauritius, New South \Vales, and the Philippine Islands.
The first adhesive stamp is sued, the one-penny black of Great Britain, was made by a more advanced process. The original steel die, having been hard ened. was impressed a number of times upon a softened steel roller which in turn was hard _ened, and under pressure rolled upon a plate from which the stamps were printed. By this means of transfer, as many impressions could he made on a plate as desired, and the full sheets of these early issues contained 240 stamps. This method of engraving and transfer, with some improvements, is employed at the present time and is utilized in the manufacture of the stamps of many countries. Another method in
use has been the setting of separate electrotypes of a stamp side by side and then recasting them as a solid plate. Lithography has also been employed as a convenient and cheap method for producing stamps in quantity. Some countries have also made stamps by the use of ordinary type and rule, the design being repeated as many times as it was desired to have stamps in the sheet. Type-set stamps vary one from another.
This is caused by slight differenees in the type or its spacing, and in the cutting of the rule used for borders.
The (.011)111011 method of printing envelope stamps is by embossing, there being in this case two (lies, one fitting into the other; the paper being placed between these and the tlat surfaee of one die inked, a stamp is prodneed in which the raised portions are white and the level por tions are inked. This method has been employed in the printing of a few ad hesive stamps, notably those of Great Britain of the issue of 18I1.
Provisional issues of stamps have been made from time to time in different countries. This has sometimes been done for the purpose of pro viding a new denomination for immediate use before it was possible to obtain a new supply of the stamps from the printers. Such provisionals are usually made by over-printing some values of stamps of which there is a surplus with a new value. This is known as surcharging. Some times lithography is resorted to in countries where the regular issues are engraved. Sur charging is also resorted to in order to increase the supply of some denominations and to de crease that of others for which there is less use than had been expected when the stamps were print ed.
There was no means employed when the ear liest issues of stamps were made to provide for their easy separation. The stamps were in tended to be cut apart, and in many cases were printed very close together. The use of a ma chine for punching small holes between the stamps, known as a perforating machine, was be gun in 854, although there are instances, even at the present time, in whieh no method of separation is employed. Another method of separating stamps is by the use of the rouletting wheel, whieh cuts through the paper between the stamps with a series of small cuts sueh as would be made by brass rule, with an edge made up of alternate dashes and spaces, in printing. This rule also is sometimes used for the same purpose, and when it is inked the stamps thus treated are spoken of as rouletted in colored lines. The eats are, in certain cases, made in zigzag or saw tooth form and are variously produced by rou letting wheels or by impressions with rule made for cutting.