My Dear, Dear Mendelssohn!
I am really glad that you have a kindness for me. To have drawn a little nearer to you is to me the happiest incident of my whole Berlin expedition. [...]
Source: Letters of Richard Wagner, Vol. 1, selected and ed. Wilhelm Altmann, trans. M. M. Bozman (J. M. Dent & Sons, 1927), No. 103