70 



SCIENCE 



[N. S. Vol.. XXVII. No. 680 



in the wliolesale paper stores, liave corruga- 

 tions on one side only. After being cut the 

 usual size, twelve by eighteen inches, they 

 should be glued two and two, so that each 

 piece would then present corrugations on both 

 exposed sides — the corrugations running cross- 

 wise, not lengthwise. 



To fill the press, proceed as follows: Place 

 on the work-table one side of the press, and 

 on it lay a sheet of thick soft paper, or the 

 ordinary " dryer " sheet may be used. On 

 this put the thin species-sheet, on or in which 

 the prepared specimen has been placed; then 

 cover with a corrugated board. On the latter 

 a specimen would be laid as in the beginning, 

 again add a soft sheet or " dryer " ; finally 

 another corrugated board; and so on until all 

 the specimens have been inserted. 



If the pile is six to eight inches high, or 

 even higher, all the better. After strapping 

 the press properly, suspend it over the stove 

 or other form of heater. The rising warm air 

 will pass freely by the corrugations and quick- 

 ly carry the moisture from the specimens. 



The next day remove the specimens, when 

 ready to put in others freshly collected. If 

 leaves or stems are succulent, or if there are 

 berries or other fruits containing very much 

 moisture, five or six hours' drying will scarcely 

 sufiiee, as it will in case of ordinary speci- 

 mens; in that event, they would be allowed to 

 remain in the press longer. 



In a few stubborn cases it is not possible 

 to arrange twigs, leaves or flowers to best ad- 

 vantage until they have lost some of their 

 moisture. It would be well to place such occa- 

 sional specimens in the old-fashioned press, 

 or between " dryers " under some pressure for 

 a short time, possibly over night; and then 

 transfer them to the warm-air press to be 

 quickly completed for the herbarium. 



It is desirable to have the rope, which is 

 used to suspend the press over the heater, 

 follow the upper edge but pass under the two 

 straps or cords that secure the press and 

 furnish the pressure on the specimens; the 

 weight of the packet itself will then continue 

 the necessary pressure — which otherwise the 

 shrinkage by loss of moisture would tend to 

 lessen. If the press is set on the hot register 



or radiator, or on an iron support over a 

 heater, it will be desirable to have a short 

 spring inserted in each of the straps, so that 

 the slack will be promptly and effectually 

 taken up as the drying proceeds. 



If a small oil stove or a lantern is used to 

 induce the current of warm air — usually the 

 case when one is off on an extended expedition 

 — it is quite necessary to have the press three 

 feet or more above the heater. Then a piece 

 of canvas or thick muslin, a yard wide, must 

 be drawn around the press closely, hanging 

 down so as to form a chute or sleeve to prop- 

 erly direct the warmed air. 



The " soft " sheet separating the two speci- 

 mens that are between each two corrugated 

 boards, might be the ordinary " dryers " used 

 in the old-style press, as signified above, pro- 

 vided, however, that they are not hard or firm. 

 It is very desirable to have something easily 

 indented by thick parts, otherwise they will 

 injuriously press into the corrugated boards. 

 The Eiker Company, that first made this kind 

 of press furnished a layer of cotton batting 

 for the soft intermediate sheet; but it does not 

 prove satisfactory on continued use. Some- 

 what similar material, perhaps that which is 

 delicately faced, " dress wadding," might be 

 entirely satisfactory. I confess that I myself 

 have not yet passed the experimental stage 

 touching this part of the work. 



The suggestion that specimens dried so 

 quickly and thoroughly would be exceedingly 

 brittle does not seem to have proved true; but 

 even if that should be the case, the specimens 

 are much improved in this respect by follow- 

 ing Dr. Millspaugh's method of poisoning, 

 namely, by using some glycerine in the cor- 

 rosive-sublimate solution. After use in the 

 tropics in making an enormous number of 

 herbarium specimens, I can say that the prin- 

 ciple embodied in this plant-press seems to 

 be abundantly sanctioned by experience. Not 

 only that, but it is possible to quadruple or 

 quintuple the work accomplished. Besides, 

 mouldy specimens — even when made in rainy 

 seasons or in the moist tropical countries — • 

 are wholly unknown to this new press. 



W. A. Kellerman 



Ohio State University 



