I'm interested in this thread as I plan to visit the Hypogeum next year and was doing a bit of reading up on it when I stumbled across this story.
The timing of the visits by Miss Jessup (cited as 1940s on many sites) and Walters (obviously pre August 1940) bothered me as there didn't seem to be much window of time for the events to occur and I've managed to find this link to the original article which has been republished by Borderlands Science.
http://journal.borde...e-cavern-world/
There is no mention in the article of Jessup being employed by the British Embassy, she merely states that she was visiting friends on Malta in the mid 1930s. (This would make her recounting of the story to Crabbe in 1960 around 25 years after the event).
Later in the article Crabbe states that she is an Englishwoman, i.e. not an American tourist as sometimes claimed.
The article states that Walters visited Malta in 1939 ( by the time the article was published Malta was beseiged (btw it was never taken by the Axis so the Nazis didn't use the tunnels).
If her recollection is correct and the children disappeared between her 2 visits a few months apart then that would make the events occuring in a window of around 1933 - 38 probably in summer or autumn as she states the weather was very hot on her first visit. (Malta tends to be cool and often foggy in the winter).
This would obviously make the tragedy (if it happened) very recent when Walters visited.
Interestingly Jessup's account makes no mention of the cries of the children being heard for weeks afterwards. I also note that she heard the story of the disappearing children from a friend who "called me to read an item from the Valetta paper" implying that she herself never actually saw the published article but was told about it over the telephone.
Edited by Collie2, 16 November 2012 - 12:54 PM.