1918] Nichols & St. John, — Corrugated Boards 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 lengthwise. 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 df 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. 
