T. Coan on the Eruption at Hawaii. 



241 



lateral outlets, or burst again to the surface by raising the super- 

 incumbent crust into ten thousand tumuli, cracking it in every 

 direction and tilting it at every angle. In this way, the hardened 

 stream becomes an irregularly laminated mass of unequal thick- 

 ness, with a surface rolling in ridges, raised in blisters, cones, hil- 

 locks and domes, depressed into valleys, indented with pits, rent 

 with yawning fissures, frowning with precipices, and bristling with 

 crags. The process is somewhat like that of a superabundant 

 quantity of water forcing its way into too small or obstructed 

 channels under vast fields of ice; allowing, of course, for the 

 great difference in consistency. You will understand, that the 

 molten flood is all poured out of the fissures on the summit and 

 for a few miles down the slope of the mountain. At first, this 

 disgorgement flowed down and spread wide on the surface of the 

 mountain as blood flows down a punctured limb. This phenom- 

 enon continued until the stream had swept down some thirty miles, 

 which it did in about two days. It now came upon a plane 

 where the angle of slope was small, say 1°. Here its progress 

 became slow, it spread more widely, and refrigeration was more 

 rapid. The surface, of course, hardened first. But this refrigera- 

 ting process went deeper and deeper like the congelation of water, 

 and extended higher and higher up the mountain, until at length 

 all the lava was covered, except at occasional vents — as heretofore 

 described — for the escape of steam and gases. Meanwhile the 

 molten river careered unseen under the enormous mural ceil- 

 ing which had been formed of its own substance, in a continu- 

 ous longitudinal stream — showing itself in fiery lines, points, 

 rills and capes, as it gushed out from under the black crust at 

 the terminus of the stream. Here we could deliberately note its 

 movements, as it pushed sullenly along over the rocks, through 

 the jungle and into the mud, the pools, and water courses. The 

 process of breaking up vertically and spreading out afresh upon 

 the hardened crust, was occasioned by obstructions at the end of 

 the stream, damming up the liquid, and thus obliging the accu- 

 mulating lavas to force new passages and outlets for disgorge- 

 ment. In this way the stream was widened by lateral out- 

 gushings, divided into several channels, swayed to the right and 

 left, and raised to great heights by pushing up from below, and 

 heaping mass after mass upon what had been its upper stra- 

 tum. Often when the stream had been flowing briskly and bril- 

 liantly at the end, it would suddenly harden and cool, and for 

 several days remain inactive. At length, however, immense 

 areas of the solidified lava, four, five or six miles above the end 

 of the stream, are seen in motion — cones are uncapped — domes 

 crack — hills and ridges of scoria move and clink — immense slabs 

 of lava are raised vertically or tilted in every direction, while a 



SECOND SERIES, VOL. XXII, NO. 65. SEPT., 1856. 



31 



