The wind fell light yesterday afternoon and, heart in mouth, I decided to try firing the beach clay pots. The weather was still iffy but we could be waiting weeks for it to settle.
The essential part of firing clay is to heat the pots slowly, otherwise they will crack or even explode (and with my first experiment a few years back, I was actually ducking shrapnel). On the other hand, if they don’t get to about 600 C, the clay will not be fired at all. There are several ways of tackling this, but in a small garden with neighbours all about (and local regulations about when you can have bonfires), making a clamp is probably the most socially acceptable solution.
It is a very simple and fairly fuel-efficient method. It’s also a method that evolved very naturally and quickly under my hand when I was first fooling around with the idea with a few pinch-pots. So although it may not be the way that real Grooved Ware was fired in Neolithic times, it’s a not unreasonable hypothesis.