Tolkien had unspeicified illness that the doctor had ordered him to rest. When he wrote this letter, he had already felt better but did nothing else.
He had gotten Farmer Giles of Ham typed and now submitted it to Allen and Unwin for their thought, in spite of the fact that he let it be known was not sufficiently long for stand-alone production. Tolkien expressed that he had arranged out a spin-off and that he had another unfinished story called The King of the Green Dozen; he offered to complete them off to accompany Farmer Giles if desired.
Tolkien said that he had started again on the spin-off to The Hobbit– The Lord of the Ring. It was streaming along and had gotten insane. Tolkien had come to about Chapter VII and it was advancing towards truly unforeseen objectives. He felt that it was superior to anything its antecedent and specified that C.S. Lewis professed himself more than satisfied. Be that as it may, he cautioned Allen and Unwin, "it was no bed-time story."