What's the difference between quenchless and unquenchable?

Quenchless

---

Definition:

• (a.) Incapable of being quenched; inextinguishable; as, quenchless fire or fury.

Example Sentences:

• (1) Still, they are bust: and while they say they were suffocated by demand, all charities face quenchless need.

Unquenchable

---

Definition:

Example Sentences: