Excelsior

Samuel Loyd was one of the greatest problem composers who ever lived. In 1858, in a joking mood in the Morphy Chess Rooms, he composed a mate problem for his friend Denis Julien. It was the original "Excelsior" problem, a concept that is explained below. Julien was a problemist who boasted that he could always immediately spot the chess piece that would deliver mate in the main line of a chess problem. So Loyd gave him the following position:

Samuel Loyd, London Era, 1861

Loyd's bet Julien he couldn't pick a chessman which would not give mate in the main line. Later he wrote: "Old Denis Julien selected the most improbable piece, but the solution will show you which of us paid for dinner."

You, too, dear reader, are invited to study the position and decide: 
which white chess man is certain not to mate the black king on h1 in five moves.

Solution