MUSCUE MM TISSUE OF THE SKIN II 
however, make the scalp better adapted for fine sections than any other part 
of the skin ; and as I succeeded better with sections than by the other method, 
the scalp has received most of my attention. By compressing a portion between 
two thin pieces of deal, and cutting off with a sharp razor fine shavings of the 
wood and scalp together, moderately thin slices may be obtained. Fig. 4 
represents a perpendicular section made in this way, and treated with acetic 
acid ; the epithelium has become detached from the free surface a, ; b, c is part 
of one of the muscles near its superficial attachment, and it illustrates pretty 
well the appearance presented by them under a rather low power. They are 
distinguished from the tissue around them by their transparent and soft aspect, 
and by the abundant elongated nuclei scattered through them. Under a higher 
power the characteristic ‘rod-shaped’ nuclei become fully brought out, and 
no doubt remains as to the nature of the tissue. A good example of nuclei so 
magnified, derived from a muscle connected with a hair-follicle of the pubes, 
is shown in Fig. 5. It will be observed in Fig. 4 that the muscle has been traced 
to within a very short distance of the surface, where the nuclei became obscured 
by other tissues. 
But I afterwards found that much better sections could be obtained from 
dried specimens. A portion of shaved scalp being placed between the two thin 
slips of deal, a piece of string is tied round them so as to exercise a slight degree 
of compression ; the preparation is now laid aside for about twenty-four hours, 
when it is found to have dried to an almost horny condition. It then adheres 
firmly by its lower surface to one of the slips, and thus it can be held securely, 
while extremely thin and equable sections are cut with great facility in any 
plane that may be desired. These sections, when moistened with a drop of water 
and treated with acetic acid, are as well suited for the investigation of the 
muscular tissue, as if they had not been dried. 
Fig. r is slightly reduced from a camera-lucida sketch? of such a section, 
made in a plane perpendicular to the surface of the scalp, and at the same time 
parallel to the sloping hairs. I find that such a plane always contains the muscles 
in their entire length, the reason of which will appear shortly. In this figure 
d is the corneous, and e the mucous layer of the epithelium; 0,0... are the 
hair-follicles with their contained hairs, both have been more or less mutilated 
by the process of section; the second hair from the right being a short one, 
its bulk is seen: c,c... are the sebaceous follicles, also more or less mutilated : 
a,, a... a, are the muscles, which appear, under this very low power, merely 
as transparent streaks, and require a higher power to make out their tissue. 
? In all the sketches from which the figures that illustrate this paper have been taken, I have used 
the camera lucida, which instrument has the great advantage of ensuring correctness of proportions, 
