30 



CIRCULAR NO. 



^F 



126, BUREAU OF PLANT INDUSTRY, 



aiding in holding the filled sheets in position. The strap holding the 

 filled sheets need not be fastened each time a folder is placed under 

 them, as in carrying the portfoHo short distances the handles of the 

 portfolio give sufficient pressure to hold the specimens in place. 

 Two portfolios may be carried if many specimens are to be obtained. 

 They will hold all that one person can collect in a day. 



The press. — The best form of press (fig. 3) consists of two slat fi-ames, 

 12 by 17 inches, made from pieces of ash three-sixteenths of an inch 

 thick and three-cjuarters of an inch wide, the slats to be i)laced about 

 an inch apart, the ends and all intersections being fastened with 



Fig. 3. — A plant press before strapping together, showing construction of the slat frames and the sheets 

 of corrugated cardboard placed between the pairs of driers which separate the folded thin sheets 

 containing the plants. 



three or four wire brads, which should be securely clinched. Small 

 rivets may be advantageously substituted for the wire brads in the 

 ends of the strips of wood, since with hard usage the wdre brads are 

 more Hkely to pull out. The driers should be of heavy gray blotting 

 paper or felt carpet paper, cut llj by 16| inches. Pieces of corru- 

 gated strawboard (fig. 3), preferably with both surfaces smooth, cut 

 to llf by 16| inches, mth the corrugations running longthA\ise, 

 placed between the blotters will be found to be of inestimable assist- 

 ance in drying the plants. Two ordinary leather trunk straps may 

 be used to secure the necessary pressure. Recent experience has, 

 however, demonstrated that a heavy canvas trunk strap having a 



LCir. 126] 



