Holmes deduces that the letter was written in a hotel room based on the color of the ink and the lack of dust on the folded edges. This suggests it was likely written on a smooth writing surface, like a hotel desk.
Sherlock Holmes, he is never given a middle name. We can only speculate, and that, I think, is for the better.
Holmes has written: 'An aid to form filling'
Adrian Holmes has written: 'My portfolio'
Wendy Holmes has written: 'Protecting the Future'
Winifred Holmes has written: 'She was queen of Egypt'
Judy Holmes has written: 'Eye on Nature'
Sheriton Holmes has written: 'The castle of Newcastle'
Les Holmes has written: 'A journey in 1994...'
R. Holmes has written: 'Maynard Jackson'
E.R.T Holmes has written: 'Flannelled foolishness'
Louise Holmes has written: 'Where love begins'
Edmond Holmes has written: 'The tragedy of education'