For the entire morning, Bi Fang was busy as a bee.
He not only had to lengthen the chimney but also had to make a bellows.
The finally completed bellows resembled a large sealed gourd, with the fan blades situated where the gourd would hold water.
Only the long rod connected to the fan blades and the very bottom part were left empty.
"Leaving the bottom empty allows us to conveniently change the blades if they get damaged. Furthermore, the bellows will ultimately be placed on the ground, effectively using the earth as a seal."
Bi Fang brought over three pieces of wood, inserting two in front of the blast furnace and setting the third on top of them, securing it all with hemp ropes.
Bi Fang carved a small hole in the middle of the branch that spanned across the top, into which he inserted the long rod attached to the fan blades, allowing it to rotate freely under constraint.
