Getting at the first char of a string in Bourne shell

[Ken Braithwaite]

I am trying to peel off one at a time the letters from a variable
in the Bourne shell, ie from Bourne get B and ourne.
How can I do this?
Thanks in advance.

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Ken Braithwaite            | They couldn't hit an elephant at
                           |   this dist
These opinions are solely  |       last words, General Sedgwick
my own. I don't share.     | 
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