doolally tap

[Q] What is the origin of doolally tap? 

[A] This is an excellent illustration of the reach, not only of the Internet, but of the English language itself. The expression is certainly a British one (though now not so often heard in that form) but to find its origins we must travel to India.

In 1861, the British army established a military base and sanatorium at Deolali, about 100 miles north-east of Bombay (it is still an important Indian military centre today). One of its functions was to act as a transit camp for soldiers who had finished their tours of duty (“time-expired”, in the jargon of the time) and were waiting for a troop ship to take them back to Britain. Ships left Bombay only between November and March, so a soldier ending his tour outside those dates might have a long wait for transport.

The effects are best explained in the words of Frank Richards, who knew the camp well. He wrote in Old Soldier Sahib in 1936:

The time-expired men at Deolalie had no arms or equipment; they showed kit now and again and occasionally went on a route march, but time hung heavily on their hands and in some cases men who had been exemplary soldiers got into serious trouble and were awarded terms of imprisonment before they were sent home. Others contracted venereal disease and had to go to hospital. The well-known saying among soldiers when speaking of a man who does queer things, “Oh, he’s got the Doo-lally tap,” originated, I think, in the peculiar way men behaved owing to the boredom of that camp.

To say someone was doolally tap meant he was mad, or at least very eccentric. The first bit is obviously the result of the standard British soldier’s way of hacking foreign-sounding placenames into something that sounded English. The second part is from a Persian or Urdu word tap, a malarial fever (which is ultimately from Sanskrit tapa, heat or torment). So the whole expression might be loosely translated as “camp fever”.

We’re not sure when the term entered soldier’s jargon. The earliest example I know of is in a glossary forming part of a book with the title Rhymes of the Rookies by W E Christian, published in 1917. It would not be at all surprising to one day turn up an instance from decades earlier.

The full expression, though it’s still heard from time to time, must have already been falling out of common use when you heard it, since most reference books imply that by the 1940s it had already been shortened todoolally. That’s the way people like me learned it around that period, often as “he’s gone doolally”, meaning that somebody’s showing signs of odd behaviour. You can still often hear it, though not one speaker in a thousand can connect it to a town in India.