94 Inquiries into the Principles of Laquid Attraction. 
will, when placed contiguous to each other, recede.” When twe 
floating bodies which make opposite curves in the surface, the one 
upward and the other downward, are placed contiguous on water, 
these opposite curves have nearly a perpendicular position, and con- 
sequently the contractile force of their curved surfaces acts in the 
same direction, and in consequence of the direction in which this 
force acts, it is unable to resist the force of the surrounding surface ; 
and hence, the bodies recede from each other, one or two inches, to 
stations where the remote extremities of their opposite curves coincide 
with the common surface ; and here the bodies remain at rest, unless 
the momentum with which — were at first propelled, carries ina 
beyond these limits. (See Fig. 
The ascent of liquids in ee tubes, and between two parallel 
plates of glass, takes place on precisely the same principle as in the 
lifting pump. When two parallel plates of glass are partly immersed 
in water, and are placed perpendicularly to the common surface, if 
they have an elevation of the liquid around them, they will, when 
brought sufficiently near together to have the remote extremities of 
their elevated curves meet, have a column of water rising between 
them, and the height to which it will rise increases in the same ratio 
as the distance between the plates diminishes; and for this reason; 
their focal seat of attraction has the same extent, and acts with the 
same uniform force at all the different distances of the plates, and the 
contractile force of the surface also continues the same, but it has the 
pressure of a less column of atmosphere to resist, and this column of 
pressure diminishes as = area of the surface between the plates di- 
minishes. (See Fig. 
_ In capillary sla f ions bores, the focal seat of attraction di- 
minishes as the diameters of their bores, but the pressure of the at- 
mosphere which it resists, diminishes as the squares of these diame- 
ters ; hence, as the diameters of capillary tubes diminish, the force of 
the contractile surface which acts from the focal seat of attraction, 
has a ratio to the force of the atmosphere constantly increasing, and 
therefore as the bores diminish, the liquids ascend with this increas- 
ing ratio. Now if a capillary tube be immersed in water, and then 
be raised from the water in an inclined. position, so as to take up 2 
greater quantity than it otherwise would, it will then sustain a column 
about twice the perpendicular height that it will when the lower ex- 
tremity of the tube rests in water ; for when the tube is taken from 
the water, the pressure of the atmosphere is diminished by the upper 
