Cellar door

Speaking of random things to get excited about. This is my latest. Just started poking around, but I really want to know who said it first? Why/how/when did "cellar door" become the most phonaesthetically pleasing word in the English language. And is it more fun to form then, say, the word "hemlock?" Is it the combination of L's and R's that makes it so magical? More on this.