Now the soil was sandier; the grass changed yet again.  They had rolled under wheel by now more than one hundred different varieties of wild grasses.  The vegetation began to show the growing altitude.  The cactus was seen now and then.  On the far horizon the wavering mysteries of the mirage appeared, marvelous in deceptiveness, mystical, alluring, the very spirits of the Far West, appearing to move before their eyes in giant pantomime.  They were passing from the Prairies to the Plains.

Shouts and cheers arose as the word passed back that the sand hills known as the Coasts of the Platte were in sight.  Some mothers told their children they were now almost to Oregon.  The whips cracked more loudly, the tired teams, tongues lolling, quickened their pace as they struck the down-grade gap leading through the sand ridges.

Two thousand Americans, some of them illiterate and ignorant, all of them strong, taking with them law, order, society, the church, the school, anew were staging the great drama of human life, act and scene and episode, as though upon some great moving platform drawn by invisible cables beyond the vast proscenium of the hills.

CHAPTER XVII

THE GREAT ENCAMPMENT

As the long columns of the great wagon train broke through the screening sand hills there was disclosed a vast and splendid panorama.  The valley of the Platte lay miles wide, green in the full covering of spring.  A crooked and broken thread of timber growth appeared, marking the moister soil and outlining the general course of the shallow stream, whose giant cottonwoods were dwarfed now by the distances.  In between, and for miles up and down the flat expanse, there rose the blue smokes of countless camp fires, each showing the location of some white-topped ship of the Plains.  Black specks, grouped here and there, proved the presence of the livestock under herd.

Over all shone a pleasant sun.  Now and again the dark shadow of a moving cloud passed over the flat valley, softening its high lights for the time.  At times, as the sun shone full and strong, the faint loom of the mirage added the last touch of mysticism, the figures of the wagons rising high, multiplied many-fold, with giant creatures passing between, so that the whole seemed, indeed, some wild phantasmagoria of the desert.

“Look!” exclaimed Wingate, pulling up his horse.  “Look, Caleb, the Northern train is in and waiting for us!  A hundred wagons!  They’re camped over the whole bend.”

The sight of this vast re-enforcement brought heart to every man, woman and child in all the advancing train.  Now, indeed, Oregon was sure.  There would be, all told, four hundred—­five hundred—­above six hundred wagons.  Nothing could withstand them.  They were the same as arrived!

As the great trains blended before the final emparkment men and women who had never met before shook hands, talked excitedly, embraced, even wept, such was their joy in meeting their own kind.  Soon the vast valley at the foot of the Grand Island of the Platte—­ninety miles in length it then was—­became one vast bivouac whose parallel had not been seen in all the world.