In making the journey to the great Southwest,—­Colorado, New Mexico, and Arizona,—­if one does not know his geology, he is pretty sure to wish he did, there is so much geology scattered over all these Southwestern landscapes, crying aloud to be read.  The book of earthly revelation, as shown by the great science, lies wide open in that land, as it does in few other places on the globe.  Its leaves fairly flutter in the wind, and the print is so large that he who runs on the California Limited may read it.  Not being able to read it at all, or not taking any interest in it, is like going to Rome or Egypt or Jerusalem, knowing nothing of the history of those lands.

Of course, we have just as much geology in the East and Middle West, but the books are closed and sealed, as it were, by the enormous lapse of time since these portions of the continent became dry land.  The eroding and degrading forces have ages since passed the meridian of their day’s work, and grass and verdure hide their footsteps.  But in the great West and Southwest, the gods of erosion and degradation seem yet in the heat and burden of the day’s toil.  Their unfinished landscapes meet the eye on every hand.  Many of the mountains look as if they were blocked out but yesterday, and one sees vast naked flood-plains, and painted deserts and bad lands and dry lake-bottoms, that suggest a world yet in the making.

Some force has scalped the hills, ground the mountains, strangled the rivers, channeled the plains, laid bare the succession of geologic ages, stripping off formation after formation like a garment, or cutting away the strata over hundreds of square miles, as we pry a slab from a rock—­and has done it all but yesterday.  If we break the slab in the prying, and thus secure only part of it, leaving an abrupt jagged edge on the part that remains, we have still a better likeness of the work of these great geologic quarrymen.  But other workmen, invisible to our eyes, have carved these jagged edges into novel and beautiful forms.

The East is old, old! the West, with the exception of the Rocky Mountains, is of yesterday in comparison.  The Hudson was an ancient river before the Mississippi was born, and the Catskills were being slowly carved from a vast plateau while the rocks that were to form many of the Western ranges were being laid down as sediment in the bottom of the sea.  California is yet in her teens, while New England in comparison is an octogenarian.  Just as much geology in the East as in the West, did I say?  Not as much visible geology, not as much by many chapters of earth history, not as much by all the later formations, by most of the Mesozoic and Tertiary deposits.  The vast series of sedimentary rocks since the Carboniferous age, to say nothing of the volcanic, that make up these periods, are largely wanting east of the Mississippi, except in New Jersey and in some of the Gulf States.  They are recent.  They are like the history of