It was found to be a most effective weapon against malaria-bearing mosquitoes on the battle front. So it may be quite possible that twice in a soldier's lifetime - once as a child at home and later on the battle field - this unusual material saved him from harm.
That is the encouraging thing about any scientific development - its ultimate usefulness can never be foretold, or even guessed, at the time of discovery. Our work in the future, as in the past, will be to concentrate our efforts on really fundamental problems - the results, many of them unpredictable, will always take care of themselves. ●