There was a distinct crack from the base of my Erlenmeyer flash as I was heating it on the large hot plate, immediately followed by a light smell of burnt sugar. On carefully moving the flask to the sink it was obvious why: a crack all around the sidewall where the base meets the sloping sides, with only about 2 inches of un-cracked glass holding the base on.

Not sure whether this was due to the hotplate being slightly wider than the flask or whether it’s down to the accumulated years of use on a halogen hob rather than a gas flame, as suggested by TMM’s page when searching for a replacement. Either way I’ve ordered a newer, larger version from TMM and also a camping gas burner.

This brew meanwhile will go ahead but instead of a starter I’ll use the calculated 3 sachets of dry yeast instead. Should make for an interesting if expensive comparison.