we walked out to take observations of the locality, before taking our
trip to the summit, and the Chief told me of the way by which they
finally erected an observatory on the highest mountain of the earth.

"Five years ago the President sent for me," explained the Chief
Engineer, "and asked if I could plan an observatory on Mount Everest. I
replied that I would try to do so if the Government saw fit to place me
in charge of the undertaking. I received my commission the next day and,
calling to my aid two of the ablest engineers in the service of the
Government, we selected a site for the entrance of the tunnel and next
we searched for suitable power to do the work. We found a waterfall
twenty miles distant, where we built a power house, installed turbines
and dynamos and built an electric line to this place. We then erected a
machine shop, in which we placed our electric engines and air
compressors, and built a railroad connecting with the main line, and
after we had done that we started the tunnel. As you will observe, the
tunnel is a round bore twelve feet in diameter, and no explosives were
used in making it. We used a tunneling machine driven and operated by
compressed air, boring on the average fifty feet every twenty-four
hours, and we washed the debris away by a powerful stream of water
directed against the face of the tunnel so as not to obstruct the work.
We gave the tunnel for the first five miles a grade of one foot in ten
and from that point to the summit a grade of sixty degrees, and laid
heavy steel segment rails six feet apart bolted to the solid rock, by
this means dispensing with ties and permitting a free flow of water and
slum. We found it necessary to build a chamber within the mouth of the
tunnel sixty feet long, with automatic doors opening and shutting, to
secure an abundance of air in the tunnel, and also in the observatory.
The tunnel required no timbering, as we bored all the way through
synetic granite and encountered very little water, and when we were