I have been lead to understand/believe that Morse intended his code to be marked out on a moving strip of paper, dots and dashes, then visually transcribed by the operator at the receiving station. This would also allow for unattended reception of a message.
The operators soon began to figure out the could copy in real time by the sounds of the clicks of the scribe against the paper, and so the paper spools and the required clockwork to move it were no longer needed.
http://en.wikipedia.org/wiki/Morse_code
Vail's "research" as to which characters were used most often (or not) was quite clever, and led to what was arguably the first "data compression" scheme.