The Hammond didn’t have letters bars, since the types where placed in an interchangeable base in C-shape, which made possible to use different types and fonts in the same machine and therefore to adapt to each language.
In pressing a key, the letter was placed at the center, but it didn’t hit against the paper to print. Instead, a hammer triggered by an elastic exerted pressure to the back of the paper and pushed it against the character in order to be printed.
In principle, James Bartlett developed, for his firsts units, a semicircular keyboard disposition labelled Ideal (DHIA-TENSOR). Also adopted by Blickensderfer, it placed the 10th most used letters at the lowest row which allowed to write more than 70% of the words in English.