on Basalt , See. 
S°7 
that a number of radiated spheroids would be generated in it, 
which would probably have all their centres about the same 
distance from the ground; and, as the arranging power un- 
dergoes a gradual diminution of energy, it is not probable that 
two rows in height of them should be formed at once, as that 
would indicate a hasty process, which had prepared a greater 
mass of matter for their almost simultaneous formation. From 
these considerations, there seems no improbability in supposing, 
that in the arrangement of a mass of fluid basalt, a single layer 
of radiated spheroids would be formed, reposing on the ground 
which supported the mass. 
I have already stated, that when the radii of two spheroids 
came into contact, no penetration ensued, but the two bodies 
became mutually compressed, and separated by a plane, well 
defined, and invested with a rusty colour. I also stated, that 
when several spheroids encountered, they formed one another 
into prisms with well defined angles. In a stratum composed 
of an indefinite number in superficial extent, but only one in 
height, of impenetrable spheroids, with nearly equidistant centres, 
if their peripheries should come in contact on the same plane, it 
seems obvious that their mutual action would form them into 
hexagons; and, if these were resisted below, and there was no- 
opposing cause above them, it seems equally clear, that they 
would extend their dimensions upwards, and thus form hexa- 
gonal prisms, whose length might be indefinitely greater than 
their diameters. The farther the extremities of the radii were: 
removed from the centre, the nearer would be their approach' 
to parallelism ; and the structure would be finally propagated by 
nearly parallel fibres, still keeping within the limits of the hexa- 
gonal prism with which their incipient formation commenced ;; 
