The peat crust was four feet of black, stringy muscle that resisted the spade like cured leather.
Tomas drove the flat bronze blade of his ditching spade into the mire with the heel of his turned-shoe. The edge sliced through tangled birch roots and dead moss with a wet, tearing crunch. He leaned his body back. That let his right hip and thigh muscles take the pivot point leverage, and heaved. A thirty-pound slab of soaked black turf broke free with a hollow sucking gasp, dripping cold, reddish-brown water that smelled of iron tannin and rotten eggs.
Beside him, wagon driver Kester and young Darrow worked in rhythm, their breath puffing white in the chilly drizzle. They were cutting the air-flow trench. A four-foot-deep trough running one hundred and forty yards from the sunken moat’s edge out to the open northern slough.
“Keep the ditch floor sloped half an inch per rod,” Nessa called out from the survey station on the corduroy path. She held her sighting rod against the bank, her brass transit lined up with the trench axis. “The gas is heavier than dry air because of the sulfur dioxide content. If the trench has low spots, the gas will pool in puddles instead of venting out to the marsh draft.”
