ANTIPERSPIRANT ACTION OF ALUMINUM SALTS 129 which at some points appears white, is a result of deliberate film overexposure. These are intentionally introduced artifacts in an attempt to portray the otherwise dark tissue detail. Figure 6 is another example which depicts the aluminum plug sealing off the sweat gland pore. The observations presented in Figures 5 and 6 are representative of what proved to be the majority of cases. In some instances, aluminum was observed not only in the stratum corneum region of the duct but in the intraepidermal duct as well. Examples of this finding are presented in Figures 7a-7c, and Figure 8. In Figures 7a and b, the greenish tinge in the epidermis is again non-specific background fluorescence. As is known from Scotch tape stripping studies, not all sweat glands are . -'-• • • -.-,, :%7 - 2 •-" ? . . -.,. ... , , -: :".•.•.,• ,- .... . ß t' •. " -:" '•' ' ',•%• ":' -,-,,- ' i' '- '.•, ,,. :' :i•'. -':• : :•: "'•- •.'•""•' .: •". L" ': "•' " i(' •'• •. • Figure lO. Water-treated eccrine sweat gland secretory tubule lumen filled with products of secretion (L:lurnen boundary). sweat

130 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS restored to firing even if the entire stratum carneurn layer is removed, indicating that those glands which are still inhibited have a blockage as deep as the Malphigian layer. Figures 7 and 8 are examples of this deeper blockage. In all glands examined, by fluorescence microscopy no evidence of marin fluorescence was found in the intradermal duct or secretary coil. Figure 9 is an example of an untreated sweat gland. The control tissues were histalagically processed identically, including marin staining. Fluorescence was never observed in those tissues. Studies of the ultrastructure of other regions of both ACH-treated and control sweat Figure 11. ACH-treated eccrine sweat gland secretory tubule lumen empty (S:trace amounts of the products of sweat secretion SG:secretory granules).