John, I checked on the 'Deolali Tap' in Google and came up with these tidbits. The phrase, which describes a kind of fever or madness, believed to be caused by heat exhaustion, is much older than the WWII. The site http://www.phrases.org.uk/meanings/161900.html traces it back to 1925 and says: <The term is British Army slang, from the Deolali sanatorium, Marashtra, India and is first cited in Fraser & Gibbons', Soldier & Sailor Words, 1925:"Deolali tap (otherwise doolally tap), mad, off one's head. Old Army." The phrase is quite archaic now, even in its 'go Dolally' form. The tap is now rarely heard, but hasn't quite died out of everyday use. Francis Marion Crawford, in his Mr. Isaacs, 1882, makes the meaning of the word clear: "Unless I feared the tap, the bad kind of fever which infects all the country at the base of the hills."> Nigel Viney's Dictionary of Toponyms (snippet at http://tinyurl.com/24q5su) even traces it back to the 19th century. The word 'tap' also appears to be of Indian origin. In the above citation it is explained as 'a fever...at the base of the hills'. The Terai region below the Himalayan Foothills was feared by the British for its hot and humid climate and perennial and endemic Malaria. The citation seems to be referring to that fever. Fever is 'tap' (more phonetically 'taap') in most Indian languages and is a very common word for fever, high temperature or strong sunshine. Cassell's Dictionary of Slang (snippet at http://tinyurl.com/2b9fxq) too says so. The phrase is still used by some, as the following extract from The Telegraph of May 23, 2007 shows: http://tinyurl.com/2xf2ko . The Times too has referred to it in 2002: please see http://tinyurl.com/27rwn4. A book about the football club Leeds United and its fans, published in 2005, has the title 'Doolally'! (http://tinyurl.com/35bblc) Arvind Kolhatkar, Toronto, March 26, 2008.