John hollis RockFace - self biasing fuzz

[dylama]

while researching some common countermeasures for temperatures issues with Germanium transistors, i´ve found the John Hollis self biasing fuzz face: http://web.archive.org/web/20091228131457/http://www.hollis.co.uk/john/rockface.jpg I must confess that the self bias part of circuit its a bit confusing to me... Maybe someone in the forum could enlighten this And of course, a vero for the Rockface would be nice. Thanks in advance!

[dylama]