of Edinburgh, Session 1885 - 86 . 
669 
characteristic scales of the true wool and the larger and more 
ring-like formations. This was sketched from a fibre taken from 
a Leicester sheep. In this fibre it will be noticed that one of 
the ring-like scales is of great length when compared with the 
diameter of the fibre, or the relative length of the other scales 
above and below. When this fibre was examined with transmitted 
light, so as to render its internal structure visible, a peculiarity 
was noticed which is of very great importance from an industrial 
or technical point of view. At that part of the fibre where the 
surface was covered by the large smooth scale, the internal structure 
exhibits no sign of any definite cells, either in the medullary or 
cortical parts. Up to the extremity of the imbricated and wool- 
like scales, indications of cell structure are visible, both in the 
cortical and medullary parts, but beyond that point they cease to 
exist in either, and the whole fibre assumes an ivory-like density. 
This change in structure does not occur all at once, but seems to 
commence in the central part of the fibre, and gradually to extend 
outwards until it constitutes the formation of the whole fibre. 
This will be seen in Plate XXIV. fig. 24, which exhibits a section 
of the same fibre as Plate XXIV. fig. 23. Beyond the point to 
which the ring-like scale extends, this solid structure again tails 
off, and the fibre assumes its usual appearance. This peculiarity 
is not of very great importance when the area over which it extends 
is small, but when it becomes the general characteristic of the fibre 
it introduces serious difficulties in the way of the manufacturer, 
because the solid portion of the fibre ceases to be elastic and 
pliable, and easily breaks when subjected to flexure. In addition 
to this all these fibres resist, or are incapable of that felting action 
which is so important a feature in the true wool, and which 
depends upon the facility with which the scales of the one fibre 
interlock into those of others when in juxtaposition. These solid 
fibres also resist the entrance of all dyeing or colouring matter into 
their interior, and will only receive a surface colouring, which is 
readily removed by either chemical or mechanical means. In some 
cases the outer continuity of the scales is not accompanied by a change 
of internal structure, and when examined by transmitted light the 
cortical and even medullary cells are distinctly visible. Such fibres 
are usually known as flat kemps, because they generally possess an 
