158 Rhodora [SEPTEMBER 
The results obtained by the method just described were fully as 
satisfactory as those secured when a lantern was used as a source of 
heat, and indeed material could be dried even more rapidly. Under 
favorable conditions completely dried specimens could be turned out 
in from three to five hours: specimens in which the natural color was 
retained far more perfectly than in plants prepared by the ordinary 
slower methods of drying, and which showed no ill effects from their 
hot air treatment save a slight smoky smell which soon vanished. 
Only in exceptional cases was the imprint of the corrugations to be 
detected in the finished product. Wind and rain were two of the chief 
enemies with which we had to contend. To avoid the former we 
always looked for a sheltered pocket among the evergreens where 
the tripod could be set up. Sometimes we rigged up a make-shift 
wind-break with a pack-cloth, while in wet weather a pack-cloth 
draped tepee-fashion around the top of the tripod served the double 
end of keeping the press dry and the fire alive. These, however, are 
two enemies against which on another trip more preparation would 
be made beforehand. 
As with the lantern method, the d. f. ventilators stood up remark- 
ably well. They showed some effects of their hard usage, to be sure, 
and after being in service for a week, with the smoke constantly 
rising through their pores, they began to smell like a lot of kippered 
herring, but what real camper would object to that! And notwith- 
standing that all the ventilators were in practically continuous service 
for twenty-four days, not one was actually rendered useless. 
In conclusion, a few observations of a general nature regarding 
the relative merits of the current methods of drying vascular plants 
for herbarium specimens. The following remarks pertain more 
especially to field operations, but in large measure they are quite as 
applicable to herbarium or home practise. In the matter of driers 
or their “equivalents”’, four possibilities are open: driers, s. f. venti- 
lators, s. f. ventilators plus driers, and d. f. ventilators. Further- 
more there is the choice between various sources of artificial heat or 
no artificial heat at all. In deciding upon the relative efficiency of 
various methods, there are perhaps five principal factors to be taken 
into account: (1) length of time required to dry specimens and (2) 
quality of results; and (3) weight, (4) durability, and (5) convenience 
in handling of the drying equipment. Sufficient objections to driers 
alone are furnished by the first and third factors; to s. f. ventilators 
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