Nor did it shake free and throw out fragments, as would have happened had the test been carried out on normal concrete.

ECONOMIST: Bunker-busting

You've got ideas that are showing concrete results in improvement, not in absolute test scores, but in the progress that that school is making, we're going to fund those improvements.

WHITEHOUSE: President Obama Holds a Town Hall in New Hampshire

Hurst had previously performed a test in his garage, in which he poured charcoal-lighter fluid on the concrete floor, and lit it.

NEWYORKER: Trial by Fire