Most boys, and many girls too, have at some time or other started a stamp collection. Stamp-collecting, or, to call it (21) its correct name, philately, (22) an increasing popular hobby from as (23) as 1854 -- for less than two decades (十年) after postage stamps (24) . Today the hobby numbers (25) are not only boys and girls, but also men and women from all ranks (阶层) in society. So rapidly (26) the interest in stamp-collecting increase in the United States of America (27) in 1921 the United States Post Office found itself (28) set up a special department to (29) the needs of collectors. At present the yearly (30) of this department total over three hundred thousand dollars.
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