I have it on the tip of my hand

This is another classic uttered by “the master”.  I remember he was trying to say “on the tip of my tongue” (a word or phrase that can’t be remembered) just out of reach) but what is the mix-up?  At first I thought it was “at my fingertips” (within reach) but my “ol pal” reminded me that the phrase “tip my hand” (revealed something that was hidden, such as in a card game) was probably the culprit and I agree.  The speaker perhaps was thinking tongue or finger but his unconscious grabbed the wrong body part, as we have seen in prior malaphors.