Ћþ

In Inglish, the letter thorn represents the voiced dental fricative or the voiceless dental fricative.
Typically, the thorn is voiced when in between two vowels, but exceptions exist especially with articles, demonstratives, and pronouns.

E.g.
the -> þe
this -> þis
these -> þise
that -> þat
those -> þose
they -> þey
them -> þem
their -> þeir
there -> þere
breath -> breþ
breathe -> briþe
bath -> baþ
bathe -> bâþe
cloth -> clòþ
clothe -> cloþe
chthonic -> þónic
chthonian -> þonian
theory -> þiry
monotheism -> monoþýism