There was an angry hissing noise from one of the cauldrons, and it began to issue an acrid green black smoke that smelled like sulfur. 'Oh dear Mister Mohr!' Meserimus gasped, hurrying to the boy's side. Archimedes laughed at the mess and the liquid that was now eating into the wood of the desk. Meserimus held out an arm to keep the student away from the clearly acidic concoction.

'I'm afraid this is rather ruined. You've overheated the base solution, there is no salvaging it, I'm afraid.' He waved his hand and the solution in Mister Mohr's cauldron vanished. 'You may start again.'

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