Applying my formula here using the approximate height of the couple (1.7m) puts them at about 187m away. Not too unreasonable now is it...
Gin,
Now that you put it that way, it does not seem so unreasonable. I still have my doubts about the hypotenuse of any triangle giving an accurate measurement, however.
But if you insist on using this mathematical hypotenuse formula, I have a solution which may be satisfying. If we look at
Chapter 5 of Earth Not a Globe, the original Flat Earth work, we will find that Samuel Birley Rowbotham did not come to the figure of 3,000 miles in his conclusion; but 700 miles in his triangulation equations of the sun. This figure may have gotten lost over the 150 years of Flat Earth history. The Sun is, in Rowbotham's model, 700 vertical miles above the surface of the earth.
The confusion might have come when in a lecture when Rowbotham famously said "right now the sun is 3,000 miles away from London." Of course he meant 3,000 angular miles - he was misinterpreted to mean vertical miles.
Anyway; 700 divided by 0.0349207695 is 20,000 miles. This is well within the diameter of the earth. This figure may be more reasonable, and in retrospect fits perfectly considering that the sun is only seen for half of its circuit.
One detail we must consider is the following:
- The hypotenuse triangle assumes a side view where the ground is perfectly flat to the observer. In reality the edge of the horizon will ascend in altitude until the vanishing point is at eye level with the observer. This would shorten the hypotenuse by a margin.
Illustration:
http://i16.tinypic.com/6gejj2t.jpg