ions mean little before spectacles like this. To know that the
span is two hundred and seventy-eight feet may help realization at home,
where it may be laid out, staked and looked at; it exceeds a block of
Fifth Avenue in New York. To know that the apex of the rainbow's curve
is three hundred and nine feet above your wondering eyes means nothing
to you there; but to those who know New York City it means the height of
the Flatiron Building built three stories higher. Choose a building of
equal height in your own city, stand beside it and look up. Then imagine
it a gigantic monolithic arch of entrancing proportions and fascinating
curve, glowing in reds and yellows which merge into each other
insensibly and without form or pattern. Imagine this fairy unreality
outlined, not against the murk which overlies cities, but against a sky
of desert clarity and color.

All natural bridges are created wholly by erosion. This was carved from
an outstanding spur of Navajo sandstone which lay crosswise of the
canyon. Originally the stream struck full against this barrier, swung
sideways, and found its way around the spur's free outer edge. The end
was merely a matter of time. Gradually but surely the stream, sand-laden
in times of flood, wore an ever-deepening hollow in the barrier. Finally
it wore it through and passed under what then became a bridge. But
meantime other agencies were at work. The rocky wall above, alternately
hot and cold, as happens in high arid lands, detached curved, flattened
plates. Worn below by the stream, thinned above by the destructive
processes of wind and temperature, the window enlarged. In time the
Rainbow Bridge evolved in all its glorious beauty. Not far away is
another natural bridge well advanced in the making.

The Rainbow Bridge was discovered in 1909 by William Boone Douglass,
Examiner of Surveys in the General Land Office, Santa Fe. Following is
an abstract of the government report covering the discovery:

"The information had come to Mr. Douglass from a Paiute Indian, Mike's
Boy, who later took the name of Jim, employed as flagman in the survey
of the three great natural bridges of White Canyon. Seeing the white
man's appreciation of this form of wind and water erosion, Jim told of a
greater bridge known only to himself and one other Indian, located on
the north side of the Navajo Mountain, in the Paiute Indian reservation.
Bending a twig of willow in rainbow-shape, with its ends stuck in the