The Magic Spark: 50 Years of Radio in Australia is a vintage hardcover book by R. R. Walker. It was published in 1973 by The Hawthorn Press and is a first edition. This book is a non-fiction narrative about the history of radio in Australia, written in English language. This book is a must-read for radio enthusiasts and history buffs alike. It provides a fascinating insight into the development of radio in Australia over 50 years and its impact on the country and its people. The Magic Spark is a scarce out-of-print find for collectors and anyone interested in the evolution of Australian radio broadcasting.