What is felshing

It seems there might be a typo in your query, as "felshing" does not correspond to any commonly known term or concept. If you meant "fleshing," it typically refers to the process of removing flesh from the skin of an animal, often in the context of tanning hides. In another context, "fleshing" can refer to a technique used in illustration or animation to add depth and detail to characters or objects. If you were thinking of something different or could provide more context, please let me know, and I'll do my best to assist you!