Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
But there are other points which perhaps present greater
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difficulty. I will take an example which is easy even for those who have no knowledge of geometry. There is scarcely anyone who does not know that the Roman acre is 240 feet long and 120 feet broad, and its total perimeter and the area enclosed can easily be calculated. But a square of 180 feet gives the same perimeter, yet contains a much larger area within its four sides. If the calculation prove irksome to any of my readers, he can learn the same truth by employing smaller numbers. Take a ten foot square: its perimeter is forty feet and it contains 100 square feet. But if the dimensions be fifteen feet by five, while the perimeter is the same, the area enclosed is less by a quarter.