A Summer's Outing, and The Old Man's Story

by Carter H. Harrison

On the mountain heights, melting snows and rains fill great lakes and copious flowing rivers. These send veins more or less large, or percolate down into the earth crust, supplying the intensely heated rocks with moisture for a vast volume of super-heated steam. The steam seeks an outlet through fissures made in the plutonic rocks by volcanic forces and through seams in the upper crumpled and pitched stratified formations. Passing through these latter this intensively heated steam erodes the softer rocks into throats, recesses and pockets, and taking up minerals in chemicals solution bears them upward, meeting the cooler crust and mingling with percolations from melting snows and rains, it becomes more or less condensed and pours out in small springs. These as they flow, deposit the silicious and other mineral matter held in solution, building up the lower side of the spring, until the rim is level. Thus the spring becomes a more or less rounded pool.

The over flow now becomes very gentle and even over the entire rim. The atmosphere reaches the whole of the overflow as it spreads over the surface of the ground and causes rapid precipitation. The constant outpour causes a constant lifting of the pool and of the incrustations about it. This spreading crust is in laminae or thin sheets. As the pool rim lifts, the weight of the column of water forces some of it between the sheets and carries it hot and rich in mineral and earthy solid matter to the outer edges of the formation, where it escapes to spread the incrustation wider and wider. The streams beneath the crust gradually wear away their channels leaving open spaces above them, which give out a hollow sound when one walks over them, and in them the rippling or gurgling of flowing water is to be heard more or less, beneath the crust.

When such underflowing streams cut a large enough channel, they frequently build up new small pools more or less removed from the parent spring. In other words one vein of hot water coming from below may be the source of several pools. Yet there are many only a few yards apart, which have sources far removed from each other, or at least the steam which supplies them with their heat and solid matter in solution, has passed through widely different and distant rock formations. This is shown by the different and distinct minerals which color the water and the formations deposited by them.

The water in one pool will be comparatively pure, while close by, is that of another strongly impregnated with sulphur, depositing great tufts in yellow and brown, and still another with red borders and olive throat full of oxide of iron. Here will be a pool beautifully green, with exquisitely tinted formations, proving that copper or arsenic are held in solution; and then within a half stone's throw is still another of intense cerulean blue and a third of most delicate sapphire.

In one of the paint pots, in the "Lower basin" not over forty feet in diameter, about half of the putty is pearl gray, while the other half is a rich peach blow. I said that the overflow of the pools was generally small. I recall several small ones and a few fully thirty or more feet in diameter, from which the overflow in a calm day was almost uniform from the entire veins, and nowhere thicker than a very thin sheet of glass. And in some instances the out put was so thin as to be a simple ooze. And yet in many of such pools the boiling action in the centre was great enough to lift bubbles and turbulations many inches high. In one pool called the "Spouter" there are constant large jets lifting from a few inches up to three or more feet, a wild fearful boiling and still only a small stream ran from it. And still others which boiled furiously but had no outflow at all. It is not improbable that from these latter there are water exists below the crusts, which have been lifted up as rims or pool margins. The bubbles and turbulations are not strictly speaking from boiling hot water, but from steam rushing up and striving to escape.

MARVELOUS COLORINGS.

No ordinary stretch of imagination will enable one who has not seen them to realize the variety and exquisiteness of the tints and colorings of many of the pools. The caves of Capri near Naples, furnish not a more wondrous blue, and the grottoes of tropical seas do not afford such variety. The tints are partly derived from the minerals held in solution by the water, but are probably owing more to the reflected tones of the geyserite formation surrounding the throats, walls and margins.

One can easily understand the solution of the problem resulting in the formation and actions of the pools, and of the building of the encrustations of the plateaux, which extend over hundreds of acres. But the actions of geysers are so weird and strange that science has probably not fully explained them. I confess myself too much of a tyro to fully comprehend the more scientific elucidation, which explains the action on chemical principles. I can, however, comprehend the more practical but possibly less scientific theory, which is sufficient for me and will probably also be so for the majority of my readers. The pools and hot springs are formed at all elevations in the valleys and on mountain slopes.

THEORIES AS TO GEYSER ACTION.

The Geysers are always in the valleys and generally contiguous to the lowest points. When lifted up they are probably so raised by their own energies as builders.