This is an advert placed in a local St-Étienne newspaper by Louis Valat. It has nothing to do with derailleurs, except that I believe that Établissement Louis Valat produced the Super Rapid brand of derailleurs, amongst other bicycle related products. The advert gives an address for this business.
A bad, but entertaining, translation of the advert might be:
"We seek a good shorthand typist, with knowledge of cycle parts if possible. Beginners should abstain rigorously. Contact Mr. Louis Valat, 36, rue Voltaire, St-Étienne."
I like to abstain rigorously from a number of activities; jogging, watching 'Strictly Come Dancing' and playing tedious modern board games are some that spring to mind.
(Source gallica.bnf.fr/ Bibliothèque nationale de France)