"Think I'm a dog-goned fool?" he cried. "The idee of turnin' from our course, and measurin' along by the slew! What's the good of that?"
Finding that the old man would not aid or abet what seemed to him such complete folly, the young surveyor made another little diagram in his notebook, and explained:—
"Here is the end of our line running from the direction B,—theoretically a straight, horizontal line, though it curves over the knoll. You noticed how, coming down the slope ahead of you, I held my end of the chain up from the ground, to make it horizontal, and then with my plumb-line found the corresponding point in the ground, to start fresh from. That was to get the measurement of a horizontal line; for if you measure all the ups and downs of hills and hollows, you'll find your surveying will come out in queer shape."
The old man scratched his bushy gray head, and said he hadn't thought of that.
"Well," the young surveyor continued, "we are running our line off towards C, when we come to the slew. Our last stake is at D,—say this little thing with a flag on it. Now, what is to be done? for we must measure four rods and thirty links farther. I measure that distance from D to E, along this shore, running my new line at an angle of sixty degrees from the true course. Then, with my compass at E, I sight another line at an angle of sixty degrees from my last. I am making what is called an equilateral triangle; that is, a triangle with equal sides and equal angles. Each angle must measure sixty degrees. With two angles and one side, we can always get the other two sides; and the other angle will be where those two sides meet. They will meet at C. Now, since the sides are of equal length, the distance from D to C is the same as from D to E,—that is, four rods and thirty links, just the distance we wish to go; C, then, is the place for your corner stake."
"It looks very well on paper," said the old man, "but"—casting his eye across the bog—"how in the name of seven kingdoms are ye ever gwine to fix yer stake thar?"