height, even
supposing that it should be necessary to make some allowance for a short
elbow at the top.

Dr. Hayden's geological party gave much attention to the Yellowstone
Park while its wonders were new to the world, and observations were made
at various times during the period included between the years 1869 and
1870. The special study, and full report of the geysers became the duty
of Dr. A.C. Peal, whose descriptions and conclusions were published in
U.S. Geological Survey Report, 1878, Part II. In the final pages of his
report he quotes the leading authorities on geyser action, and applies
the principles of their theories, according to his own judgment, to the
geysers of the park. Since copies of this report are not now easily
obtained, nor even always accessible to the increasing number of
personages who visit the park, it may be well to quote from him some of
the theories he discussed and the opinions he expressed. On page 416,
beginning the chapter with the derivation of the word geyser from the
Icelandic word _geysa_--to gush, he continues:

"We now come to the definition of a geyser. It may be defined to be a
periodically eruptive or intermittent _hot_ spring, from which the water
is projected into the air in a fountain-like column. The analogy between
geysers and volcanoes has frequently been noticed and the former have
often been described as volcanoes which erupt heated water instead of
melted lava. We have italicized the word hot in the definition just
given, because springs containing a large amount of gas may simulate
geysers.

"The difference between geysers and ordinary hot springs is not readily
explained, nor even always recognized. The difference between a quiet
thermal spring and a geyser in active eruption is very marked, but
between the two there is every grade of action. Some geysers appear as
quiet springs, as for instance the Grand Geyser during its period of
quiescence. Others might easily be mistaken for constantly boiling
springs, as in the case of the Giant Geyser, in which the water is
constantly in active ebullition. This is true also of the Strockr of
Iceland. Many of the springs, therefore, that in the Yellowstone Park
have been classed as constantly boiling springs may be unsuspected
geysers. The Excelsior Geyser was not discovered to be a geyser until
eight years after the setting aside of the park. Almost all constantly
boiling springs have periods of increased activity, and t