The illustration demonstrates the different steps involved in the manufacture of leather.
Overall, the process consists of 12 steps, which involve the use of both manual labour and machinery, beginning with the collection of raw materials and ending with waxing the leather.
The first seven steps involve raw processing of the material. Initially, animal skins are collected from farms and undergo a sorting process by size before they undergo trimming for smoother edges. After this, salt is added to the material which is then left to cure for 30 days. Subsequently, it is submerged under water for between 12 and 24 hours, prior to the removal of excess hair on the surface by knives.
The remaining steps entail processing the material with substances and chemicals. Specifically, after being transferred into a spinning barrel to be pickled with salt and acid, it goes through another process of tanning in the same barrel with other chemicals for two days. The colouring and softening procedures come after, with the skin being placed in a container and mixed with oil and colouring additives. The leather is then taken out to be dried by fans, before the process is concluded by waxing by hand.