In a recent issue ofThe Mathematical Gazette (May 1910), Mr C. S. Jackson points out that certain algebraic theorems appear more difficult to some beginners than would have been anticipated, and he instances as a case in point the proof of the proposition that if , each ratio is equal to . He almost apologises (I think quite unnecessarily) for making the suggestion that some concrete illustrations of the proposition may render its simplicity more manifest, and thus prepare the way for an enunciation of the result in its most general form. The illustration Mr Jackson takes of the above proposition is:

“A regiment of 1000 men contains 130 Yorkshiremen; another of 1200 men contains 156.