What is 'taken so much stock as to make it a virtual Whitmore monopoly'?
For half of his weekly time on the air Walter always had a guest. Someone connected with the Open Air; a commodity in which Walter had lately taken so much stock as to make it a virtual Whitmore monopoly. Walter compèred the Open Air in the shape of a poacher, a sheep farmer from the back blocks of Australia, a bird watcher, a keeper from Sutherland, an earnest female who went round pushing acorns into roadside banks, a young dilettante who hunted with a hawk, and anyone else who happened to be both handy and willing. For the latter half of his time Walter merely talked.
(Chapter 5 To Love and Be Wise, http://gutenberg.net.au/ebooks08/0800551h.html#ch05)Does " monopoly" here mean that Walter speaks most of the time, without giving opportunities to his guests?

Question

What is 'taken so much stock as to make it a virtual Whitmore monopoly'?
For half of his weekly time on the air Walter always had a guest. Someone connected with the Open Air; a commodity in which Walter had lately taken so much stock as to make it a virtual Whitmore monopoly. Walter compèred the Open Air in the shape of a poacher, a sheep farmer from the back blocks of Australia, a bird watcher, a keeper from Sutherland, an earnest female who went round pushing acorns into roadside banks, a young dilettante who hunted with a hawk, and anyone else who happened to be both handy and willing. For the latter half of his time Walter merely talked.
(Chapter 5 To Love and Be Wise, http://gutenberg.net.au/ebooks08/0800551h.html#ch05)Does " monopoly" here mean that Walter speaks most of the time, without giving opportunities to his guests?

Answer

Have you ever consider choosing another book that doesn't have odd English writing ?    Blogs, news websites, even comic books can be a better alternative.