Air-holes formed, fissures sprang and spread apart, while thin sections of ice fell through bodily into the river.
After the lapse of ten or fifteen minutes, the green rind embrowns and cracks, showing through the fissures in its sides the milk-white interior.
In such situations, rooted in narrow cracks or fissures, where there is scarcely a handful of soil, it is frequently over eight feet in diameter and not much more in height.
The steaming water rises through fissures in volcanic rocks and is now depositing in the rifts a vein stone of quartz, with metallic ores of iron, mercury, lead, and other metals.
The minerals of veins are therefore constantly being dissolved along their upper portions and carried down the fissures by ground water to lower levels, where they are redeposited.
Stunted pines grew in the fissures of the rocks, and their strong roots helped the clinging hands and feet as the boy painfully climbed, slipped, and swung along, fearing every minute to come to some impassable barrier in the dangerous path.
In the afternoon, refreshed by tea, we went forward, confident of covering the remaining distance, but by a fatal chance we kept too far to the left, and then we struck uphill and, tired and despondent, arrived in a horrid maze of crevasses and fissures.
Now fissures, wherever they occur, form the trunk channels of the underground circulation. Water descends from the surface along these rifts; it moves laterally from either side to the fissure plane, just as ground water seeps through the surrounding rocks from every direction to a well; and it ascends through these natural water ways as in an artesian well, whenever they intersect an aquifer in which water is under hydrostatic pressure.