sses with waves of her plumy tail.

"Do you think we shall hear from father, Frank?"

"We ought to; you know he said in his last letter he was getting
settled at the Presidio, and would soon send for us."

"Takes twelve days to bring a letter from San Francisco. I suppose
it'll take us longer to go there; seems to me he might get ready for
us while we are on the road," said Henry, lugubriously. "I'm getting
mighty tired of opening and shutting these gates."

"You forget father has to visit all the posts where companies of his
regiment are stationed. That will probably take him all of a month
longer."

"And we must go on opening and closing gates and running errands in
Arizona? But come; let's get a swing on 'em and watch for the
expressman afterwards. We haven't much time before retreat."

The gates closed a fort which we had built since our arrival in
Arizona. Peeled pine logs, ten feet long, had been set up vertically
in the ground, two feet of them below the surface and eight above,
enclosing an area of a thousand square feet, in which were
store-rooms, offices, and quarters for two companies of soldiers and
their officers. At corners diagonally opposite each other were two
large block-house bastions, commanding the flanks of the fort. The
logs of the walls were faced on two sides and set close together, and
were slotted every four feet for rifles. At one of the corners which
had no bastions were double gates, also made of logs, bound by cross
and diagonal bars, dovetailed and pinned firmly to them. Each hung on
huge, triple hinges of iron.

The two boys returned to the gates, and, setting their backs against
one of them and digging their heels in the earth, pushed and swung it
ponderously and slowly, until its outer edge caught on a shelving log
set in the middle of the entrance to support it and its fellow. Then,
as the field-music began to play and the men to assemble in line for
retreat roll-call, they swung the second gate in the same way, and
braced the two with heavy timbers. The boys then reported the gates
closed to the adjutant.

As the companies broke ranks and dispersed the boy sergeants went to
the fifth log, to the left of the gates, and swung it back on its
hinges. This was one of two secret posterns. On the inside of the
wall, when closed, its location was easily noticeable on account of
its hinges, latches, and braces; on the outside it looked like any
other log in the wall. Their work bein