weight made the border suddenly slough off beneath my feet. General
Washburn noticed the sudden cracking of the incrustation before I did,
and I was aroused to a sense of my peril by his shout of alarm, and had
sufficient presence of mind to fall suddenly backwards at full length
upon the sound crust, whence, with my feet and legs extended over the
spring, I rolled to a place of safety. But for General Washburn's shout
of alarm, in another instant I would have been precipitated into this
boiling pool of alum. We endeavored to sound the depth of this spring
with a pole twenty-five feet long, but we found no bottom.

Everything around us--air, earth, water--is impregnated with sulphur. We
feel it in every drop of water we drink, and in every breath of air we
inhale. Our silver watches have turned to the color of poor brass,
tarnished.

General Washburn and I again visited the mud vulcano to-day. I
especially desired to see it again for the one especial purpose, among
others of a general nature, of assuring myself that the notes made in my
diary a few days ago are not exaggerated. No! they are not! The
sensations inspired in me to-day, on again witnessing its convulsions,
and the dense clouds of vapor expelled in rapid succession from its
crater, amid the jarring of the earth, and the ominous intonations from
beneath, were those of mingled dread and wonder. At war with all former
experience it was so novel, so unnaturally natural, that I feel while
now writing and thinking of it, as if my own senses might have deceived
me with a mere figment of the imagination. But it is not so. The wonder,
than which this continent, teeming with nature's grandest exhibitions,
contains nothing more marvelous, still stands amid the solitary
fastnesses of the Yellowstone, to excite the astonishment of the
thousands who in coming years shall visit that remarkable locality.[J]