1918] Nichols & St. John,— Corrugated i3oards 155 



bulky specimens. Altogether only about 75 boards were taken into 

 the field. The general scheme followed was that described by Collins 

 and needs little further comment. As a source of heat an ordinary 

 kerosene lantern was used. Incidentally, in this connection, it was 

 found that, in addition to an abundant supply of oil, a stock of extra 

 wicks was essential, since, with the lantern running continuously day 

 and night, the wick had to be well trimmed at least once and prefer- 

 ably twice a day. About a month of each summer was spent in per- 

 manent camp, and during this period the press was hung in a special 

 shelter: the first summer in a makeshift tent, roofed with tarpaulin 

 and walled with boughs; the second summer in a small hut constructed 

 out of tar-paper and scantlings. The latter part of each summer was 

 spent partly in localities where "hotel" accommodations were avail- 

 able, partly in trips of about a week's duration through an uninhabited 

 wilderness where all luggage had to be packed and carried. On these 

 latter jaunts little attempt was made to dry specimens properly, but 

 at the hotels it was customary to run the press as usual, suspending 

 it by means of home-made wire hooks between the backs of two chairs. 

 The experience gained during these two summers demonstrated 

 conclusively the worth of d. f. driers. As a rule plants were left in 

 the press for 24 hours, the press being reversed at the end of 12 hours 

 to insure even drying toward both ends of the press. This length of 

 time sufficed to completely dry ordinary specimens, and even Mer- 

 tensia, a notoriously difficult subject, was out of the press within 

 three days. It should be interpolated, however, in the light of more 

 recent experience, that boards cut with the corrugations running 

 crosswise give more satisfactory results than those with corrugations 

 running Iength^\ase. With the latter there is a tendency for parts 

 lying near the center of the press to dry slowly, a tendency which is 

 quite obviated where the corrugations run crosswise. The specimens 

 prepared by the method just described are all that could be desired, 

 and are noticeably superior to those prepared with the help of s. f. 

 driers alone. Even Mertensia makes a fairly presentable specimen, 

 retaining its color at least much better than any other specimens we 

 have seen. As might have been expected, by the end of the first 

 summer all of the ventilators showed unmistakable signs of service, 

 and many of those that had had the misfortune to lie next to bulky 

 specimens were pretty much out of commission. But that they stood 

 up well under the test is demonstrated by the fact that many of them 

 were again used throughout the second season. 



