I suspect now G.C. is George Cooper. It seems he wrote at least one more book "Yeddie .. "; https://books.google.co.uk/books?id=LAbfBAAAQBAJ&lpg=PA76&ots=l5mrfwqE03&dq=%22crocker%20%26%20cooper%22&pg=PA76#v=onepage&q&f=false