What is this symbol? Rev War Pension Documents

I am working on https://catalog.archives.gov/id/54598404?objectPage=18

In the signature block, there are two unclear items for me; a word and a symbol.  The line after his signature is "Jus Peace & [word] in & for [symbol] County"

Is the symbol the double-s legal symbol for 'section' or something else.  I think it's a stand-in for the county name "Middlesex"?

Thanks for any help you can give!