FLAX-STEM ANATOMY IN RELATION TO RETTING. 19 
made by ie ned hands? In other words: (1) What test 
which may be confirmed by examination of the fiber in the dry state 
_ gives positive indication that retting is complete? (2) what test 
from the viewpoint of the inexperienced worker gives the strongest 
- indication that retting is complete? 
The various ways that have been tried in this study for mechani- 
cally separating the cortex from the wooden core are listed as fol- 
- lows: 
Group 1.—Loose-core tests: The cortex is held stationary. 
(1) The loose core test made toward the root end of the stem. 
(2) The loose-core test made toward the panicle end of the stem. 
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ic. 14.—Step 1 in the loose-core test of retting flax fibers. The cortex is shoved back 
from the wooden core so as to leave several ‘centimeters entirely free from fibers. 
Group 2.—Leaf-scar tests: The wooden core is held stationary. 
(3) The entire girth of cortex is peeled away from the wooden core, 
beginning at the basal end of the stem and keeping the cortex 
parallel to the cere. 
(4) The same as test 3 except that the peeling is started at the panicle end 
of the stem. 
(5) Peeling the cortex from the base end of the stem toward the panicle 
and keeping it at a 30° to 45° angle to the wooden core. 
(6) The same as test 5 except that the peeling is started at the panicle 
end of the stem. 
(7) Pulling the entire cortex away from the wooden core, starting at the 
base end of the stem and keeping the cortex at right angles to the core. 
(8) The same as test 7 except that the test is started at the panicle end 
of the stem. 
As an indication that retting is incomplete, the resistance to separa- 
tion of the cortex from the wooden core is almost invariably strongest 
at the nodes. Fiber branches and wood branches cling to the Teaf 
