IV PREFACE. 



stamped envelopes, and post cards of all the nations of the world, 

 to the number of nearly 200,000, and since that time there has been 

 a constant accretion from this and other sources. 



There have been many methods of exhibiting postage stamps, but 

 the scheme adopted by the United States National Museum is with- 

 out doubt an improvement over any other, especially in the matter 

 of detail. The principle is the same as that followed by the British 

 Museum and as exemplified in the former cabinet of the Post Office 

 Department — namely, a series of vertical sliding frames in which 

 the specimens are mounted. The two plates accompanying the text 

 of this publication show the character of the installation of the stamp 

 collection which is located in the northwest court of the older build- 

 ing of the United States National Museum. This is an interior 

 court, lighted entirely from overhead, with no direct light ever 

 falling upon the exhibits installed therein. It is an ideal place for 

 a stamp exhibit, the lighting being very nearly perfect, and it is only 

 in the late afternoon hours of the dark winter days or upon exceed- 

 ingly dreary stormy days that artificial light is necessary, which is 

 then supplied by high arc lights directly over the stamp cases. 



The cabinets that have been built, and in which the United States 

 Government collection is now installed, may be briefly described as 

 follows: There are two cases, each 20 feet 2 inches long, 6 feet 7 

 inches high, and 2 feet 8^ inches deep, constructed in three sections 

 for convenience in moving. They are made of hard cherry with dull 

 mahogany finish, a cornice and simple trimmings giving an exceed- 

 ingly rich appearance; the interior is of white pine, except as other- 

 wise stated. The lower part of the case is arranged for storage and 

 provided with doors. The upper part, measuring 3 feet 21 inches 

 from a counter shelf to the top of the cornice, contains the sliding 

 frames, of which there are 185 in each case, or 370 in all, a number 

 that may of course be at any time increased by adding to the case 

 length. 



The individual frames, made of hard cherry with duU mahogany 

 finish, measure 31^ inches high by 29 f inches deep on the outside 

 and 27i by 21^ inches in the opening; the thickness of the frames 

 is H inch, and when fuUy drawn out they are exposed to a depth 

 of 23 i inches, with an extension into the case of 6^ inches, which 

 provides the necessary leverage. Both sides are used and are glazed 

 with Belgian negative glass. The frames slide on cherry strips, 

 fixed to the top and bottom of the interior space of the cabinet, and 

 their upper and lower rails are grooved to within an inch of the 

 front. In the lower groove are mortised four brass trunk rollers, 

 projecting one-eighth inch, to raise the frame above the bottom 

 strips, but the upper groove contains only one such roller, placed 

 about 1 inch from the back to prevent friction as the frame is started 



