54 
TENTH REPORT. 
CAPILLARITY OF CELLULOSE. 
J. B. Dandeno. 
It should not be necessary to define such a common term as capillarity, 
but, in view of the fact that there are, in technical physics, at least, two 
meanings, distinct and even opposing, and in common language another 
more indefinite meaning, it is thought well to make ourselves perfectly clear. 
Some use the term capillarity to include attraction, and also surface tension. 
Others use it to mean a certain peculiar kind of attraction, or at least at- 
traction between a solid of peculiar form, and a liquid. What is meant here 
by capillarity is that attraction which takes place at touching distances 
between a solid and a liquid. We employ capillarity, then, as a definite 
term, and, if we use it negatively, as well as positively, it is quite general 
in application. Capillarity, will, therefore, depend upon the nature of 
the solid and the liquid, with respect to the affinity of the one for the other; 
upon the affinity of the solid for air; upon the amount of mass of the solid, 
and upon its form, whether in flat sheets, fibers, or other masses. 
The amount of capillary attraction will, therefore, depend upon several 
factors. In the case of cellulose which is one of the most baffling of chemical 
compounds, it is necessary to select one of the best known of the forms and 
concern ourselves with this alone. 
Swedish filter paper which is made of practically pure cotton, and which 
has been cleansed from all traces of oil or of substances of an oily nature, 
seems to be fairly well adapted to problems in capillarity. Raw cotton 
hairs are quite different from the cotton of filter paper, and also quite different 
from absorbent cotton. In fact, absorbent cotton becomes absorbent 
because of the capillarity of such cotton, and this capillary attraction is 
developed chiefly because the raw cotton has been treated with an alkali 
sufficiently strong to destroy all the oily matter ordinarily adherent to the 
hair. So that the capillarity of cotton fibre will depend upon the treatment 
to which raw cotton has been subjected in processes of manufacture. 
Swedish filter paper is fairly uniform in composition and in capillary at- 
traction, and it was found to be the most satisfactory form for the purpose. 
Its specific gravity is 1 . 13. 
In order to test the force and the rapidity with which such fiber attracts 
water, an arrangement was made with glass tubes in which was a continuous 
strip of filter paper about 15 mm. wide, folded loosely and drawn into the 
glass tube. The object of having the paper surrounded with glass was to 
keep the air from coming into contact with the water while ascending in 
the tube. If strips of filter paper be exposed to the open air, it is quite clear 
that, at a certain point, the drying power of the air would be so great as to 
render it impossible to raise the liquid higher, even though the capillary 
attraction had not yet been satisfied. These glass tubes containing strips of 
filter paper being, on inside diameter, about five mm., were set up vertically 
with the lower end just immersed in the liquid which was being subjected 
to examination. 
Various means were employed to determine at any given time just how 
high the ascending liquid had crept, but the simplest and easiest method 
