SIO 
solids, with chemical qualities of the atoms, as necessary to 
explain many of the conditions of articles used for comfort 
and convenience ; on which, indeed, their usefulness for the 
purposes of buildings, clothing, and even for food depended. 
Calling especial attention to the action of the surfaces of 
all solids as exercising mechanical forces, and also rapidly 
allowing the peculiar influences of heat, light, and elec- 
tricity, to be absorbed or reflected, and the action also 
of the surfaces of fluids upon air and gases, he then 
called attention to the attractions of a surface of liquid, for 
the surface of a solid body: considering this a force of great 
and overlooked importance in nature, because called capillary 
attraction, and usually understood only to relate to exceed- 
ingly small surfaces, and hair-like columns of fluids, as 
the examples of power. 
He proceeded to shew that a very large class of unex- 
plained phenomena was referrible to the agency of capillary 
attraction, a fuller acquaintance with which might lead to the 
surmounting of many scientific and practical difficulties. 
The process of carbonizing steel — the penetration of the 
carbon into all parts of a substance not supposed to he 
porous — was incidentally referred to, as showing how little is 
known of some highly important processes beyond the mere 
results. Mr. Pearsall undertook to show that the force 
termed capillary attraction, was in that special form no more 
than a practical definition of a much more general form, 
exercised not only upon small quantities of matter, but 
upon a large scale. To exemplify the operation of capillary 
attraction, recourse was had to a conical glass vessel, 
terminating in a tube having a bore equal to a human 
hair. When the vessel was inverted and immersed in 
water, the liquid, in defiance of the laws of gravitation, rose 
up into the tube (which was not immersed) to a height of 
several inches above the water. This was ascribed to the 
