@ Josey, I agree that it Looks very similar to the CC but that makes no sense at all
Scc... or Icc.. or Lcc. If it were an I then it should be Ick....
I also agree that "u" is the most likely, Su... or Lu... or Iu...
@ Rosinish, although Insch has been suggested by a number of helpers, I would have thought that if he said he was Born near somewhere, he would have taken the next largest town - Aberdeen - and not a villiage that I imagine most People of 1769 would not have heard of. Even now it only has a Population of 2.282 (Appologies if anyone from Insch is reading this)
Having said that, it does look like Insch in the document