Oozing Rucksacks

From the Courier-Mail:

OOZING rucksacks, harmless puffs of smoke and the failure of the latest apparent attempted bombings in London suggest a link between this week's attacks and the July 7 atrocities, experts said today.

The four bombs that apparently failed to explode on Underground subway trains and a double-decker bus yesterday bore similarities to the type of Al-Qaeda-style devices used in the suicide attacks earlier this month, which killed 56 people, explosives specialists said.

Witnesses spoke of seeing a lard-like substance oozing from one of the would-be bombers' backpacks after it failed to go off, suggesting the presence of an explosive mixture such as acetone peroxide which was used on July 7, the experts said.

That substance - made from household items such as sulphuric acid, hydrogen peroxide and acetone - deteriorates over time and becomes harmless if it passes its use-by date.

"If the bombers from July 7 and yesterday all loaded their rucksacks together two and a half weeks ago, you might expect a substantial amount of the explosive to have disappeared by this week," chemist Andrea Sella of University College London said.

I apparently am ill-supplied. To my knowledge, there has never been any sulphuric acid in my house. My car battery, sure, but not in house. In any event, it all sure seems amateurish.

[Update 0955 EDT]

Oops! Richard at Hyscience reminds me that drain cleaner is H2SO4.