Michael Perelman wrote:
<<What is meant by the reference to "the general"? Engels was very interested in military affairs, so much so that some of his articles were assumed to have been written by a real general. The tone of the article suggests a bit of contempt in the name, or am I misreading Negri?>>
I don't know how Negri uses it, but it Engels's nickname among friends, as "The Moor" was Marx's nickname. To catch the warmth in the name, read Yvonne Kapp's two volume biography of Eleanor Marx -- a really beautiful work which should be much more widely known. It is out of print but worth whatever you might have to pay for a second hand copy.