¶ Unused air mail stamps fit such a situation admirably. For these special adhesives are seldom printed in large quantities. Because their use is limited, in the majority of cases, to prepaying matter carried by airplane, issues of stamps in lots of less than 100,000 copies are the rule, rather than the exception. Quite frequently, the smaller governments will confine a special issue to five or ten thousands copies—a fact which means that on this broad globe of ours only a handful of people can ever hope to own such a specimen, regardless of their wealth or position in life. And this number of possible possessors is materially lessened because of the fact that most specialists build their collections with blocks of four stamps of each issue as well as single copies. ¶ Looking back only three short years ago at the prices which air mail stamps commanded during the spring of 1933, the reader will quickly realize the soundness of the foregoing remarks. Ascribe it to what you will: their popularity, their intriguing history, or their limited supply—one principal fact will stand out. The simple fact that air mail stamps have, as a whole since this time, _doubled_ in value, with many instances of issues which trebled and quadrupled their former price. ¶ For the purpose of illustration, we can choose a few air mail adhesives issued by our own government for no one could question the integrity behind the postal paper of the United States. The first triumvirate of values brought out in 1918 was in six, sixteen, and twenty-four cent denominations. During April of 1933, the market price for this set was $2.50. Today, it is offered at $4.00. ¶ The 1923 set, however, shows a much greater appreciation in value when percentage of increase is considered. On the date mentioned above, this issue sold for $1.25, and today commands at least $3.00 for fine specimens. And the famous “Graf Zeppelin” issue has soared from $10.00 in 1933 to a present-day figure which varies from $35.00 to $40.00 per set, depending upon condition. ¶ And to bring the reader still another amazing instance, we can refer to the special stamp printed in October, 1933, in commemoration of the Century of Progress flight made by the Graf Zeppelin. Just about two and a half years have passed since this fifty cent adhesive left the printing presses at the Bureau of Engraving. Today, copies of it are bringing $3.00, with many dealers unable to supply them at that price because of their scarcity and unabated demand. ¶ We could, without question, continue this parade of statistics through the entire list of air stamps issued by all countries of the world, but lack the space to make such a lengthy comparison. If, however, any reader has any lingering doubts, we invite him to make a complete check-up. To his amazement, we can foretell, he will find that our statements are conservative indeed.