[1] Around the time he ended his studies at the gymnasium, his brother took him on a trip to America to attend the Centennial Exposition in Philadelphia.

[1] Following his citizenship, the newly minted Charles Martel moved to Council Bluffs, Iowa, where he worked as an estate manager as well as an assistant to a lawyer.

While in Council Bluffs, Martel heard of the Newberry Library in Chicago and by 1892 had gained employment there as an assistant cataloguer under the esteemed librarians Dr. William F. Poole and James C.M.

[1] Putnam sent Martel and Hanson to libraries located across the nation to find a classification system that would work with the collection.

This began a two-year-long controversy between the two giants of the library as each criticized the other over perceived slights in the decisions about changes needed to adapt the DDC.

[1] In the end the only real winner was Charles Ammi Cutter, who agreed to allow Martel and Hanson to make whatever changes they needed to his EC.

The Library of Congress Classification (LC) system drew heavily on various other catalogues then in existence such as the Index Medicus for the medicine section.

In 1900, shortly after beginning the work of re-classifying the library's collection, Martel married the widow Emma (McCoy) Haas, who died in 1906 after giving birth to their son, Rennie.

As one contemporary stated, the two were "greatly influential in drawing up the Vatican Norme, perhaps the best of modern cataloging codes, and one which goes far to reconcile European and American practice.