He then hired Robert Yelf to work with him, and sent some moulds over to Uncle Isaac, who dug out roots for him, and procured crooks for knees and breast-hooks. When he had filled these orders, there was a lull, and Charlie went to farming and making preparations for boat-building in future.
Having now mastered the principles of surveying by means of a Gunter’s scale and chain, which Ben possessed, and a cross staff which he had made under his father’s directions, he began to practise by measuring the cleared land on the island and the points, and making and platting the different pieces. He was anxious to learn the use of the compass, and to run lines by it; but he had no land compass, and here, with most boys, the matter would have rested; but unaccustomed to yield to difficulties, Charlie resolved to make a boat compass serve his turn—the very one that had been the instrument of saving his life in the snow squall.
His first attempt was to make a tripod. Upon a piece of oak board he drew a circle two inches larger than the compass, with projections at each side six inches long, and sawed it out by the marks: he then drew another circle, two inches inside of this, and sawed down to it, cutting out the wood so as to leave two projections on each side, two inches wide and two long: in each of these he cut a slot on the underside, also in one of the end ones, to receive a tenon cut on the end of each of the legs. By heating a wrought nail he made rivets, upon which his legs traversed easily, and fastened the compass to a wooden peg in the centre. A land compass has brass perpendiculars at each end of the base upon which it sits, with slits in them, by which to sight. In order to represent these, he made two holes in the ends of his base, in line with the needle of the compass, and put in two knitting needles, making them perpendicular with a plumb-line: thus, by setting up a stake, he had three objects in range, and could sight accurately. A land compass has a spirit level on its frame, by which to level it, screws to keep it in place, and a ball and socket joint upon which it moves; but by spreading or contracting the legs of his tripod, and by means of a plumb-line (the great resource of all mechanics in emergencies), he contrived to depress, elevate, and adjust the compass, measure land, and run a line accurately, and in a manner which Ben, after looking over his work, pronounced correct.
“Survey the island, Charlie,” said Ben; “I should like to know how much there is in it. I will carry the chain for you, and help you about measuring the points.”
“Don’t you know how much land you bought?”
“No; I bought it for so much; had it for more or less—what Mr. Welch’s father had it for when he bought it; I expect it overruns.”
“I should like to know, too,” said Uncle Isaac, who had come to the island that morning. “I’ve heard the most talk back and forth about this island: some say Ben hasn’t got the land he paid for, some say he’s got more. You need three to work in the woods. I’ll carry the chain.”
“I had it for seventeen hundred acres,” said Ben.
“Well, there’s all that, if not more.”