I really recommend the whole chapter this quotation comes from, and for that matter the whole book (Wind, Sand, and Stars, or in the original French, Terre des hommes). It’s a fantastically optimistic take on the relation of humans to technology (the specific example is airplanes, but the argument is quite general).
oh, and just for completeness, the quotation in its original form:
« Il semble que la perfection soit atteinte non quand il n’y a plus rien à ajouter, mais quand il n’y a plus rien à retrancher. Au terme de son évolution, la machine se dissimule. »
or in the not-quite-literal translation by Galantière:
“In anything at all, perfection is finally attained not when there is no longer anything to add, but when there is no longer anything to take away, when a body has been stripped down to its nakedness”
[Here’s the immediate context in French: http://wikilivres.info/wiki/Terre_des_hommes/III and in English: http://books.google.com/books?id=Ep-h7MuxLiIC&lpg=PP1...]