Yet in the retrospect of his Leipzig days it seems to have crossed his mind that he might have spent them more wisely.

"O that I could recall the last two years and a half,"[49] he wrote to Kaethchen Schoenkopf, and he warns a male correspondent in Leipzig to "beware of dissoluteness."[50] And the state of his health during the greater part of this time in Frankfort was such as to strengthen this mood.

Immediately after his return from Leipzig he was threatened with pulmonary disease, and the state of his digestion became such as to alarm himself and his friends.

On December 7th he was attacked by a violent internal pain, and for some days there were the gravest fears for his life.

After two months' confinement to his room there was a partial recovery, but it was not till the spring of 1770 that his health was completely restored.
[Footnote 49: _Werke, Briefe_, Band i.