A Room with a View

Being in a room opposite to the side of a window, the bottom of which was just the height of my eye, I observed that up to the edge of the window I could see 42 courses of bricks in a wall on the opposite side of the street; but moving towards the window 5 yards, I found that I could see 72 courses. What is the height of the window, supposing the breadth of the street to be 12 yards, and 4 courses of brickwork to the foot in height?

The Ladies' Diary, London, 1790

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