Etymology of "usquebaugh-baul"

[Caoimhin O Donnaile]

Since I wrote yesterday, Rody Gorman pointed me in the direction of 
Dwelly and the old spelling “baoghal”, and there sure enough are both 
“uisge-beatha baoghal” (under “baoghal”) and “uisge baoghal”, and he gives 
both as meaning “whisky four time distilled”:

   http://multidict.net/multidict/?word=baoghal&sl=gd&tl=en&dict=Dwelly_WA
   http://multidict.net/multidict/?word=uisge&sl=gd&tl=en&dict=Dwelly_WA

Dwelly refers to Armstrong’s dictionary (1825, mid-Perthshire), which 
gives “uisge baoghail” as a translation (or Gaelic explanation) for 
English “alcohol”:

   http://multidict.net/multidict/?word=alcohol&sl=en&tl=gd&dict=Armstrong_WA

It looks to me as if Martin Martin, a Gaelic speaker, was thinking more of 
the Gaelic word “ball”, limb, whereas Dwelly and Armstrong obviously have 
“baoghal”, danger.

I can’t see “baoghal” being pronounced so as to be written “baul” in 
English spelling.  But it is from Old-Irish “báegul”, so who knows?

To add to the complication, there’s an adjective “baoth” (< baeth/baíth) 
meaning silly, stupid, giddy, and that describes the effects of whisky 
well enough.  And that gives “baothail” which is often written “baoghal”. 
The two words seem to have been rather entangled since way way back.
They both seem to have connotations of scaring people by jumping on them 
by surprise.

Caoimhín