hugh pointed at the stove upon which simmered away an evil brew , acow gum , it 's made from animal bones , your mum could n't stand the pong , that 's why she 's gone down the wash-house ... i ca n't smell a thing , '' he wheezed , '' look at this your granddad got us , '' he held up a thick piece of rubber , `` straight off the wheels of the 39 bus he said , if he ever gets caught they 'll throw away the key !