MUD. VOLCANOES AND GEYSERS 373 
due to its peculiar form. An observer states that, ‘‘ The bore is 
eight feet in diameter at the top, and forty-four feet deep. Below 
twenty-seven feet it contracts to nineteen inches, so that the turf 
thrown in completely chokes it. Steam collects below; a foaming 
scum covers the surface of the water, and in a quarter of an hour 
it surges up the pipe. The fountain then begins playing, sending 
its bundles of jets rather higher than those of the Great Geyser, 
flinging up the clods of turf which have been its obstruction like a 
number of rockets. This magnificent display continues for a quar- 
ter of an hour or twenty minutes. The erupted water flows back 
into the pipe from the curved sides of the bowl. This occasions a 
succession of bursts, the last expiring effort, very generally, being 
the most magnificent. Strokr gives no warning thumps, like the 
Great Geyser, and there is not the same roaring of steam accom- 
panying the outbreak of the -water.” ; 
The same author thus describes an eruption of the Great 
Geyser, which occurred about two o'clock in the morning : “A vio- 
lent concussion of the ground brought me and my companions to 
our feet. We rushed out of the tent in every condition of disha- 
bille and were in time to see Geyser put forth his full strength. 
Five strokes underground were the signal, then an overflow, wet- 
ting every side of the mound. Presently a dome of water rose in 
the centre of the basin and fell again, immediately to be followed 
by a fresh bell, which sprang into the air fully forty feet high, 
accompanied by a roaring burst of steam. Instantly the fountain 
began to play with the utmost violence, a column rushing up to the 
height of ninety or one hundred feet ayainst the gray night sky, 
with mighty volumes of white steam cloud rolling after it and 
swept off by the breeze to fall in torrents of hot rain. Jets and 
lines of water tore their way through the clouds, or leaped high