Letters On the English or in French Lettres Philosophiques is a series of essays from Voltaire based on his time living in England from 1726 through 1729.  These essays were first published in 1733 and are sometimes compared and contrasted with Todqueville’s Democracy In America.    It is also considered an attack on the French government and as such was suppressed.

Selections from this classic work may be read here:

http://www.bartleby.com/34/2/8.html

In addition, a look at the philosophy and life of Voltaire may be found here: