Very challenging sentence, but here you go: --not to be on any account compared with the noble fellows who fill the Volunteer corps-- the punctuation "--" indicates where it starts and ends. So, what you asked about "fill the Volunteer corps--pot-house heroes" is not together. It is: Some of the British section, those tremendous patriots who demonstrate but do not fight *** pot-house heroes, and others of that kidney, had just distinguished themselves by mobbing Mr. Schreiner in the streets. Now, a pot-house is a (drugname)-house. You'll find several "houses" where the name is typically illegal drugs because it is extensively used or grown/manufactured there. So while this excerpt speaks highly of the volunteer corps, the others are apparently terrible people. May I ask what you're reading? It sounds interesting!