In an earlier version (Typescript B) of 'The Quest of Erebor', of which Typescript C was published in
Unfinished Tales, Merry questioned Gandalf further about Thrain's map and key, and how Sauron had not taken them from him. Gandalf began by explaining that it was 9 years after Thrain had left his people when he found him; and he had been in the pits of Dol Guldur for 5 years at least. He then said:
I do not know how he endured so long, nor how he had kept these things [the map and key] hidden through all his torments. I think that the Dark Power had desired nothing from him except the Ring only, and when he had taken that he troubled no further, but just flung the broken prisoner into the pits to rave until he died. A small oversight; but it proved fatal. Small oversights often do.
How silly (and fatal) of Sauron,
and how brave of Thrain, to have endured so much for so long!
