William Le Queux 
Tracked by Wireless [PDF ebook] 

“Mr. William Le Queux retains his position as ‘The Master of Mystery.’… He is far too skilful to allow pause for thought; he whirls his readers from incident to incident, holding their attention from the first page to the close of the book.”
He never fails to produce the correct illusion. He always leaves us panting for more—a brilliant feat.”
“Mr. Le Queux is always so refreshing in his stories of adventure that one knows on taking up a new book of his that one will be amused"