Yes," said Mr. George; "they are very easy indeed."

The stairs were, indeed, very easy--the steps being very broad, and the
"rise," as it is called, of each one being very small. Rollo and Jennie
went on very gayly; and, as they kept about half a turn, of the
staircase in advance, they were generally just out of sight of Mr.
George and Mrs. Holiday, who followed somewhat more slowly behind.
Jennie would have been afraid to have gone thus out of sight of her
mother and uncle were it not that she could hear their voices all the
time close at hand, and their footsteps, also, on the stairs.

From time to time, as our party ascended, they met other parties coming
down. When there were children in these descending parties, they tripped
along very lightly in coming down; but Rollo and Jennie soon found
themselves growing quite tired. So they stopped to rest. After stopping
a moment, Rollo's mind seemed to swing, like a pendulum, to the opposite
extreme.

"Let us run, Jennie," said he, "and then we shall get up quicker."

"No, it will tire us more to run," replied Jennie.

"But then we shall get up all the quicker," said Rollo, "and so it will
not make any difference. We may as well work hard and have it over quick
as to work not so hard and have it last a great while."

"Well," said Jennie, "then let us run."

This reasoning of Rollo's was very specious and plausible, but it was
very erroneous notwithstanding; for it is found by experience that the
whole amount of fatigue which results from doing any given piece of work
is by no means the same when it is done quickly as when it is done
slowly. A horse, for example, if you allow him to jog along slowly, at
the rate of three or four miles an hour, can travel forty miles a day,
for months at a time, without growing thin; but if you drive him at the
rate of eight miles an hour, he cannot stand more than ten miles a day
for any long period. That is, he can do four times as much in amount,
with the same degree of fatigue, if you allow him to do it slowly.

It is curious that the case is precisely the same with a steam engine. A
steamer can cross the Atlantic with a very much smaller supply of coal,
if she goes slowly, than if she goes fast. One might imagine that it
would take just twice as much coal to go ten miles an hour as would be
required to go five; but in reality it takes more than four times as
much--the higher rate of speed requiring a very disproportionate
expend