Quote from Stephen Lockyer on Sunday 4th August, 2019, 09:04

Think of the alphabet as a line and count drips.

Quote from kisanna12 on Thursday 15th August, 2019, 13:27

I've got [spoiler]h+11=S o+5=T n-5=I N M - what of the last two columns?[/spoiler]

Quote from Stephen Lockyer on Wednesday 11th September, 2019, 18:12

Drips down increase the letters on the alphabet, and  drips up decrease.

The last letter is a [spoiler]G[/spoiler] as a hint.

Quote from kisanna12 on Thursday 26th September, 2019, 13:43

Thanks!

I now realise that the trick for the last letter was to [spoiler]consider not only the drops in the line above Y but also the ones next to it[/spoiler]