Dear Madam,

In all haste—for several days my house has been full of friends, come on a visit from the provinces—herewith the address: M. Da Costa, 40 rue Gay-Lussac, Paris. Since I have only seen the old gentleman once and very briefly, he will certainly not remember me. But all you need say by way of introduction is that Marx obtained the address expressly for you through his son-in-law Longuet—who is a friend of young Da Costa’s. 2