In Reply to: Soft soap posted by Graham Cambray on February 16, 2009 at 20:59:
: : Do you know the origin of the phrase "to soft soap"?
: At http://www.answers.com/topic/soft-soap%20they%20have:
: This colloquial expression alludes to liquid soap, likening its slippery quality to insincere flattery. Its figurative use was first recorded in 1830.
Stuart Berg Flexner, in two references, says it dates back to 1830. But no further details.