It's a matrix with its very own jargon

You may recall that I was a little nervous of asking the builders when the first slates would go on the cob barn roof.
The massive oak trusses went up so quickly, and since then a veritable crisscross of timbers with their own precise taxonomy is being added so that by the time the roof is ready for the slates to go up, the rain will have to dodge a great deal of wood before it can splash to the floor.
Across the trusses are the mighty purlins, and today three quarters of the roof is covered in vertical rafters. I worry for the ancient cob walls, but am reassured by the structural surveyor that they will happily take the weight without groaning to a heap of cobby rubble.
In the bonus February sun the builders perch like happy parrots all over the roof, hammers and tools strapped firmly into their belts.
I suspect that by the end of the week the mass of horizontal battens will start to go up, and then it's just a matter of putting the jargon in a place where my brain will retain it for further recall, and it will be slate time.
Oh, and I did ask, and the answer is within the next fortnight.