The celebrated Suspension Bridge which spans Linwood Gorge – its chains once spanned the Thames – has seen many tragedies in its seventy years, but none more sinister than that with which this latest of Colonel Gore’s cases concerns itself. Staggering in the simplicity of its achievement, incredible in the selection of its victim, the murder of Dr. Sidney Melhurst presents itself to the reader, as it did to the police and to Gore himself – an apparently unsolvable mystery. Baffled for space by a parallel trail, in the end, inch by inch, and at grave personal risk, he drags the truth to light. The two trails converge, and meet in the certainty which, in some measure, explains the title, Q.E.D. – a certainty as agreeable to the reader as to Colonel Gore.
Alister McAllister (1877-1943) was an Irish novelist and playwright who wrote detective stories under the name "Lynn Brock" and other works under the name "Anthony Wharton".