What were M.F. Chamans's calculations about how much trade would gain by the burning of Paris? In &quot;That Which Is Seen, and That Which Is Not Seen&quot;, Bastiat (1850) writes:

What will you say, Moniteur Industriel? what will you say, disciples of good M.F. Chamans, who has calculated with so much precision how much trade would gain by the burning of Paris, from the number of houses it would be necessary to rebuild?

What were M.F. Chamans's calculations about how much trade would gain by the burning of Paris? (Also, who was M.F. Chamans?)
Auguste Louis Philippe de Saint-Chamans (1777-1860), also known as Vicomte de Saint-Chamans, was a French politician who served as the master of requests to the Council of State in 1820, Councilor of State in 1827, and the deputy for the Marne from 1824 to 1827. He also wrote a number of economic treatises. (The &quot;M.F.&quot; is, I believe, incorrect and actually just &quot;M.&quot; for Monsieur in the original.)
Unfortunately, Bastiat remembered Saint-Chamans's quote incorrectly -- though his critique of the idea is just as valid.
Saint-Chamans argued that the Great Fire of London (1666) in its destruction led to a net economic gain (due to spending to rebuild) of 1 million pounds (or 25 million French francs).
You can read more about this fallacy here or read Saint-Chamans's work in its original French: M. le vicomte de Saint-Chamans, Traité d’économie politique suivi d’un apercu sur les finances de la France, vol. 1 (1852).