is expected to carry, they are few or many, stout or slender, but they share their joint labor with absolute justice,—­not one does more, not one does less, than its just proportion.  The outer end of the spokes is received into the deep mortise of the wooden fellies, and the structure appears to be complete.  But how long would it take to turn that circle into a polygon, unless some mighty counteracting force should prevent it?  See the iron tire brought hot from the furnace and laid around the smoking circumference.  Once in place, the workman cools the hot iron; and as it shrinks with a force that seems like a hand-grasp of the Omnipotent, it clasps the fitted fragments of the structure, and compresses them into a single inseparable whole.

“Was it not worth our while to stop a moment before passing that old broken wagon, and see whether we could not find as much in it as Swift found in his ‘Meditations on a Broomstick’?  I have been laughed at for making so much of such a common thing as a wheel.  Idiots!  Solomon’s court fool would have scoffed at the thought of the young Galilean who dared compare the lilies of the field to his august master.  Nil admirari is very well for a North American Indian and his degenerate successor, who has grown too grand to admire anything but himself, and takes a cynical pride in his stolid indifference to everything worth reverencing or honoring.”

After calling my companion’s attention to the wheel, and discoursing upon it until I thought he was getting sleepy, we jogged along until we came to a running stream.  It was crossed by a stone bridge of a single arch.  There are very few stone arches over the streams in New England country towns, and I always delighted in this one.  It was built in the last century, amidst the doubting predictions of staring rustics, and stands to-day as strong as ever, and seemingly good for centuries to come.

“See there!” said I,—­“there is another of my ‘Eyes and No Eyes’ subjects to meditate upon.  Next to the wheel, the arch is the noblest of those elementary mechanical composites, corresponding to the proximate principles of chemistry.  The beauty of the arch consists first in its curve, commonly a part of the circle, of the perfection of which I have spoken.  But the mind derives another distinct pleasure from the admirable manner in which the several parts, each different from all the others, contribute to a single harmonious effect.  It is a typical example of the piu nel uno.  An arch cut out or a single stone would not be so beautiful as one of which each individual stone was shaped for its exact position.  Its completion by the locking of the keystone is a delight to witness and to contemplate.  And how the arch endures, when its lateral thrust is met by solid masses of resistance!  In one of the great temples of Baalbec a keystone has slipped, but how rare is that occurrence!  One will hardly find another such example among all the ruins of antiquity.