Fulling Mill Humpy - Yellow

Deer hair is hollow

Deer hair is hollow, which is why the Humpy floats the way it does. The body is a doubled layer of it, hair pulled over hair, so the fly is carrying trapped air along its whole length rather than just balancing on hackle points. Almost nothing else floats as long in fast turbulent water. It is not a subtle fly and it is not trying to be one: it is the pattern for pocket water and rapids.