Abstract
According to Pillow and other botanists the spiral cracks exist in the tracheid wall of the green part of compression wood. Whereas the writer could not find any spiral cracks in green wood, but could find them after treating the material with alcohol, 72% sulphuric acid or copper oxide ammonia.
The writer's experiment reulted to the conclusion that lignin exists in quantity, forming spiral layer, in the, secondary layer of tracheid wall. So, it is the writer's opinon that-if the wood were treated to be dried or done to be changed by some other phisico-chemical treatments the spiral cracks come to appear in the secondary layer of tracheid wall.
