Thanks madpants and Erato
I must say I thought "mechanic" too but I wasn't sure what demand there would have been for that occupation in a small rural village which didn't even get the railway for another 6 years.
Maybe that's why he became a shoemaker

Also elsewhere on the certificate the clergyman has made his capital "M"s much more pointed, though his writing is so atrocious I could believe he was inconsistent on this.
I had a quick look in a street directory for 1852 (2 years earlier) and the sum total of traders listed were as follows:-
1 inn keeper
3 publicans
2 grocers
1 haberdasher
1 police constable
1 schoolmaster
1 postmaster
2 clergymen
2 doctors
Needless to say my guy is not among them.