They can make lanterns out of paper or cloth, carry them at night while visiting neighbors, checking animal barns, and the like.
The lantern oil is now made from animal fat.
Animals that died in the wild and whose meat cannot be eaten can be used to render oil.
So Ma Lin has enough animal fat.
Teaching primitives arithmetic is a very laborious task.
If they are willing to listen to a lecture for an hour a day, it's already good.
He doesn't have a blackboard, so he writes and draws on planks with charcoal pencils.
The planks are planed out.
He has many more things to do here.
He has not yet successfully improved the loom; in its current form, it's very clumsy.
The spoked wheel has not been successfully made, and there is no clue as to how to proceed. The problem with the spokes is that they are difficult to install.
