Analysis of information sources in references of the Wikipedia article "Chain (unit)" in English language version.
Since the foregoing Report [on the best route for the Forth and Clyde Canal] ... was delivered ... , Mr Smeaton has discovered that, notwithstanding the care and pains he took to be correct, he has committed an error, in supposing the Scotch chain, with which the measures of the length of the tract of land were taken, to consist of seventy feet each, whereas, in reality, it consists of seventy-four
1610 W. FOLKINGHAM, Art Survey.