"Very well," the older man continued. "At eight o'clock sharp, then, you will raise quickly the curtain in front of the smaller hole, and drop it again, doing this three times, allowing the hole to remain open for ten seconds each time. Do that every five minutes for half an hour, or six times in all, to allow for any possible variation of time in your watch. By the way, you had better have two watches in the event of one of them stopping or the hands catching, or something of that sort, because a month's work will depend on getting that signal. But I think I can trust you."
"You can, indeed, Mr. Masseth," said Roger. "But what shall I be doing during those two months? Am I to remain alone in camp?"
"Hardly," said his chief, smiling. "The Survey does not waste men that way. Mr. Mitchon has written me that Mr. Herold desires you should have an insight into the varied work of the department, and I have arranged for another topographic aid to meet me on the other side, so that, except for this heliograph signal, which I must remind you is excessively important, you will have finished with the work here."
"Then what?"
"Death Valley and the Mohave Desert," replied his chief. "It is perhaps a little hard to send you into a hot section of the country at this time of year, but, you see, you cannot go too far away because of your engagement with the sun on a morning two months hence—by the way, if it is cloudy, which is so rare a contingency as scarcely to be reckoned on, signal the next morning at the same hour—so you must stay near by, and the most interesting work at hand is that being done in the waterless country."
Photograph by U.S.G.S.
Twenty-seven Miles from Water.
Shelter camp in Great Dry Desert, life being sustained by constant relays from distant wells.