Marx on Bakunin, from a letter to Engels written in Manchester dated 1863:

Bakunin has become a monster, a huge mass of flesh and fat, and is barely capable of walking any more. To crown it all, he is sexually perverse and jealous of the seventeen year-old Polish girl who married him in Siberia because of his martyrdom. He is presently in Sweden, where he is hatching “revolution” with the Finns.

They just don’t make insults like they used to.