﻿CHAPTER III. 

 ON THE METHODS OF SECTION CUTTING. 



In these extensive studies of solidly silicified and often bulky fossil plants, it 

 was necessary to devise a new method of work in order to fairly preserve the origi- 

 nal trunks and at the same time cut a large number of the fruits borne by them in 

 the best form for sectioning. Hence an explanation of methods may appropriately 

 be given before passing on to the description of the structures revealed. 



In the case of cycad 214, the first fruit studied with care was chiseled out by the 

 writer, but this proved a difficult and tedious work, requiring many days. Moreover, 

 the continued strokes of the chisel finally jarred the fructification loose while a 

 considerable portion of the peduncle yet remained embedded in the armor, although 

 the upper portion was secured intact and none of the essential structures were lost. 



It was then thought possible to make a series of small drill holes, parallel to 

 each other and distributed about a fruit circularly or elliptically, and then chisel out 

 the partitions between these holes and thus secure complete fructifications, as seated 

 on the cortex, together with the connecting bundle system and its origin in the 

 xylem. This process proved possible with drills run by compressed air, but much 

 too slow for extended use. 



Tubular drills were next tried ; and these, with various devices for use on dif- 

 ferent shafts, have proved speedy and effective, though their use requires skill, time, 

 knowledge of the general structures, and constant watchfulness, lest the cylindrical 

 core containing the fructification be broken away and shattered into pieces before 

 the drill can be stopped. No fruits were actually lost in this way. The drills 

 were made of ordinary iron and steel tubing, steel being little or not at all better 

 than iron. They varied in inside diameter from 35 mm. to 75 mm., with walls from 

 2 to 4 mm. in thickness. Each drill was made 150 mm. long, excluding 60 mm. 

 of the upper portion, as provided with a close-fitting sheath of suitable size for 

 fitting the drill to a vertical 35 mm. shaft revolving at the rate of 100 or more revo- 

 lutions per minute. Through the sheath, as set a little below the edge of the drill- 

 tube to form a trough about the revolving shaft, were drilled from two to four holes 

 in order that the inside of the drill might be kept full of cool water flowing in a 

 constant stream ; this is very necessary. When, as in certain sizes, the shaft was 

 of the same diameter as the inside of the drill, two rows of alternating holes were 

 drilled through the wall of the tubular portion just below the lower end of the 

 shaft. Into these a steady stream of water was then projected. This plan worked 

 very well. 



Before drilling, the trunk was carefully blocked up in a heavy box with refer- 

 ence to a particular fruit, then firmly cemented in with plaster and exactly oriented 

 beneath the drill with reference to the estimated position and slant of the fruit and 



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