on the Cohesion of Fluids. 7 1 
properly considered, in this as well as in the former case. It 
will appear that these experiments by no means exhibit an 
immediate measure of the mutual attraction of the solid and 
fluid, as some authors have supposed. 
Sir Isaac Newton asserts, in his Queries, that water ascends 
between two plates of glass at the distance of one hundredth 
of an inch, to the height of about one inch ; the product of the 
distance and the height being about .01 ; but this appears to 
be much too little. In the best experiment of Musschenbroek, 
with a tube, half of the product was .0196; in several of 
Weitbrecht, apparently very accurate, .0214. In Monge’s 
experiments on plates, the product was 2 .6 or 2.7 lines, 
about .0210. Mr. Atwood says that for tubes, the product is 
.0530, half of which is .0265. Until more accurate experiments 
shall have been made, we may be contented to assume .02 for 
the rectangle appropriate to water, and .04 for the product of 
the height in a tube by its bore. Hence, when the curve be- 
comes infinite, is greatest ordinate is .2, and the height of the 
vertical portion, or the height of ascent against a single ver- 
tical plane .14, or nearly one-seventh of an inch. 
Now when a horizontal surface is raised from a vessel of 
water, the surface of the water is formed into a lintearia to 
which the solid is a tangent at its highest point, and if the 
solid be still further raised, the water will separate : the sur- 
face of the water, being horizontal at the point of contact, 
cannot add to the weight tending to depress the solid, which 
is therefore simply the hydrostatic pressure of a column of 
water equal in height to the elevation, in this case one-fifth of 
an inch, and standing on the given surface. The weight 
of such a column will be 50 J grains for each square inch; and 
