Eugen Goldstein did not contribute directly to the discovery or understanding of the atom. He was a German physicist known for his work on canal rays, which are positively charged particles that travel in the opposite direction of the cathode rays in a discharge tube.

Here's why his work is not directly related to the atom:

* Canal rays were later identified as positively charged ions: This was crucial in understanding that atoms can lose electrons and become positively charged. However, it wasn't a direct discovery of the atom itself.

* The discovery of the atom is attributed to John Dalton: His atomic theory in 1803 proposed that matter is made up of indivisible particles called atoms.

* Later advancements in atomic theory, like the discovery of the electron by J.J. Thomson and the nucleus by Ernest Rutherford, further shaped our understanding of the atom.

While Goldstein's work on canal rays was important in the development of atomic physics, it wasn't directly about the atom itself. It contributed to the understanding of charged particles within atoms and helped pave the way for later discoveries about atomic structure.