[Mr Harcourt] came in, in the dark, locking the outer door after him, and waited by the telephone until Neville’s call came through from London. When the bell stopped ringing, he lifted the receiver in the library. As soon as Neville had spoken his little piece, Harcourt chipped in. Nobody could hear him through these sound-proof doors, and Hamworthy couldn’t possibly tell that his voice wasn’t coming from London. In fact, it was coming from London, because, as the ’phones are connected in parallel, it could only come by way of the Exchange. At eight o’clock, the grandfather clock in Jermyn Street struck—further proof that the London line was open. The minute Harcourt heard that, he called on Neville to speak again, and hung up under cover of the rattle of Neville’s receiver. Then Neville detained Hamworthy with a lot of rot about a suit, while Harcourt walked into the dining-room, stabbed his uncle, and departed by the window.
The telephone in Absolutely Elsewhere is crucial to establishing an alibi for the murderer, placing him in London when the crime was committed. Sayers takes pains to locate the two telephones, in the library and in the hall, together with the victim in the dining-room with his back to the library door and emphasises that the two phones are ‘connected in parallel’. This, at first, would seem to rule out a telephone call over an extension such as a Plan 5 using Bellset no. 20 (introduced in 1925) which provided limited intercommunication. It is also necessary to confirm that the library telephone was guaranteed to be connected to the Exchange, which might not have been the case with an extension. Sayers also determines that the call is connected by a telephone operator who is manually timing the call and announcing ‘Three minutes’ at the end of each charging period. This was, of course, written 19 years before the introduction of Subscriber Trunk Dialling in 1958.
by Owain Carter