The man is using a sowing sheet, swinging his arms rhythmically, throwing a handful of seed grain to either side. The horses are harrowing the seed in to let it germinate and hide it from the rooks! It must be good light land, because the the earth is still in furrows and only will get one cultivation with the harrows. Mum recalled as a young girl having to fill a big metal pail with seed from a bag on the head, and Granddad would refill his sheet, each time he reached the end rig, where she was waiting with the pail. Oats were Ok she said, but the bushel weight ( ie density) of wheat seed made it a hard carry.
Robert Stevenson
