It is known that when wool is treated with the sulphuric acid of commerce
or in strong dilute sulphuric acid, the surface scales of the fiber are
liberated at one end, and appear, under a low power, as hairs proceeding
from the body of the fibers. Wool may remain thus saturated in the acid
for several hours, without appearing to undergo any further change, as
far as is revealed by the microscope. When treated in mass in a bath of
sulphuric acid, strength 60° B., for several minutes, and afterward
quickly washed in a weak solution of soda, and finally in pure water and
dried, it feels rough to the fingers, owing to the separation of the
scales. I have preserved a small quantity of wool thus treated for the
last twelve years, my object being to ascertain whether the chemical
action to which it was exposed would impair its strength. As far as I can
observe, without the aid of the proper tests, it seems to have retained
its original tenacity. Wool thus treated seems to possess the property of
resisting the ravages of the larvæ of the moth. This specimen, although
openly exposed for the period named, suffered no injury from them. Under
the microscope, the lubrications appear to have resumed their natural
position, and appear finer.
From these experiments it would seem not improbable that a new article of
commerce might be produced from wool thus treated, considering that it
seems to be moth-proof.
I find in practice that when sable brushes are washed in a weak solution
of pure phenic alcohol and afterward in warm water, the moth worm will
not eat them. In this way I preserve sable brushes. I mention this
chemical fact because it shows that a change of this material is brought
about by the phenol as to its edibility, and this may explain why wool
treated with sulphuric acid is rendered moth-proof.
I find that when brain matter has been subjected to a solution of weak
phenic alcohol, weak alkaline solutions afterward applied fail to
separate its nerve-cells on the process of maceration. (This is probably
owing to its albuminoids being coagulated by the action of the phenol.)
When brain matter is subjected to a weak solution of soda alone, the
nerve-cells are easily separated by maceration, and well adapted for
microscopic use.