s resulting from this play of polar forces are
various, and exhibit different degrees of complexity. Men of science avail
themselves of all possible means of exploring their molecular
architecture. For this purpose they employ in turn, as agents of
exploration, light, heat, magnetism, electricity, and sound. Polarized
light is especially useful and powerful here. A beam of such light, when
sent in among the molecules of a crystal, is acted on by them, and from
this action we infer with more or less of clearness the manner in which
the molecules are arranged. That differences, for example, exist between
the inner structure of rock salt and crystallized sugar or sugar-candy, is
thus strikingly revealed. These differences may be made to display
themselves in chromatic phenomena of great splendor, the play of molecular
force being so regulated as to remove some of the colored constituents of
white light, and to leave others with increased intensity behind.

And now let us pass from what we are accustomed to regard as a dead
mineral to a living grain of corn. When _it_ is examined by polarized
light, chromatic phenomena similar to those noticed in crystals are
observed. And why? Because the architecture of the grain resembles the
architecture of the crystal. In the grain also the molecules are set in
definite positions, and in accordance with their arrangement they act upon
the light. But what has built together the molecules of the corn? I have
already said regarding crystalline architecture that you may, if you
please, consider the atoms and molecules to be placed in position by a
power external to themselves. The same hypothesis is open to you now. But
if, in the case of crystals, you have rejected this notion of an external
architect, I think you are bound to reject it now, and to conclude that
the molecules of the corn are self-posited by the forces with which they
act upon each other. It would be poor philosophy to invoke an external
agent in the one case and reject it in the other.

Instead of cutting our grain of corn into slices and subjecting it to the
action of polarized light, let us place it in the earth and subject it to
a certain degree of warmth. In other words, let the molecules, both of the
corn and of the surrounding earth, be kept in that state of agitation
which we call warmth. Under these circumstances, the grain and the
substances which surround it interact, and a definite molecular
architecture is the