Abstract
A new technique with a simple apparatus is introduced in observing and measuring the diameter of hair directly on cross section.
About 10 hairs are arranged in parallel in place of the film of a slidef rame of cardboard; about 10 holes are made both on the upper and lower edges of the opening of the slide-frame, through which holes the hairs are fixed for easy manipulation's sake.
A 10 percent celloidin solution is poured to fill the opening of the slide-frame so that the hairs sink in the solution. In about 1.5 hours there is produced a hardened celloidin with the hairs embedded in it; the hardened celloidin is removed from the slide-frame. The hardened celloidin is sectioned to make a right angle to the arranged hairs. The section thus obtained is adequately placed under a microscope and observed by a reflected light instead of a penetrating light.
During the process a special holder consisting of a pair of wood is employed to secure the section placed under the microscope.
