"Well, it is difficult, anyway," said the boy.
"Extremely so. The intense color, the glowing rays of the sun seldom shielded by any clouds, the lack of vegetation and the absence of landmarks all help to confuse the idea of distance, so that you cannot trust to your eyes to map a point until you have been there."
"And how do you get there?" queried the boy in wonderment.
"Climbing. There is an Indian trail on this side that helps a little, and there are three roads down to the river on this side and one on the north. This one through trail, called the Cameron or Tourist trail, has been partly rendered passable, so that by herculean effort and with trusted and well-trained animals it is possible to cross. Usually, however, the trail is left in loneliness, for there is absolutely no traffic between Utah and Arizona. Except for a little corner in each, these States are more widely separated than if an ocean rolled between them."
"And how about these corners?"
"Well, Utah can get to hers by taking a little trouble, but the northwest corner of Arizona is No Man's Land, so far as any jurisdiction goes."
"But you say animals can be made to tackle those trails. I should have thought that kind of work would kill any animal that tried it."
"It's pretty hard to kill a burro," answered Masseth, "and I've never lost one. Indeed, in all the Survey work I've done in the Grand Canyon, I've only had one accident, and that was a case absolutely unavoidable. I lost one of my favorite horses that time."
"How did it happen, Mr. Masseth?" asked Roger.
"It was on the north side of the Canyon," began the topographer, "and I was working on an outlying butte with my assistant. We had made quite a number of bench marks and I was working out the contours—those are the lines on a map which show the height or elevation of any point—while my assistant was sitting beside me, making out some of the necessary calculations. We were working out from a little side camp, the two of us, the rest of the party being at headquarters, several miles away. I was drawing in at full speed, because I wanted to change from that side station that evening, and for a couple of hours I suppose we had not exchanged a word, except with relation to figures.