The Disertación sobre el arte de volar, a Lima referee's report on a proposal to carry the mail by air

When a man of no standing offered the government of Peru to keep despatches moving through the air during a war with Britain, the chief cosmographer was ordered to report, and then wrote a dissertation to settle the public argument. It contains a wing-loading calculation, a muscle-mass argument, an account of the tail as a control surface and a description of clothing acting as a parachute - and it concludes that flight is providentially impossible, and would be wicked if it were not.