I found a web site giving details for lots of different types of wood and what their ideal burning condition should be in terms of moisture content. For Ash (type of wood, not the white stuff!), it seems that I should be aiming for a specific gravity of about 0.65.
Well, of course I needed to find out what my test logs were now in terms of SG, so after carefully wrapping them in cling film to keep them dry I floated them in water and measured how deep they sank when held vertically. The logs being roughly cylindrical, all I had to do was divide the immersed length by the total length and that gives me the SG i.e how heavy the logs are compared to water. OK so far?
It looks like they are currently at about 0.85 which it seems is typical for fresh cut Ash. The rest is easy. Assuming the volume stays the same I can work out the weight which would give an SG of 0.65. All I have to do is to weigh the log periodically until we get there.
Here's a pretty graph, which I will update from time to time.
Is all this really necessary? Naah! In any case my measurements are not strictly accurate. Also, apparently Ash logs will burn when fresh cut, but they use up a lot of their heat steaming off the water content so they burn hotter when dry.
But its fun.
If you like that kind of thing.