Help To Identify Coin Please

Looks to be Maximianus (286 to 305AD).
Reverse is in my abbreviated book - I think the figure is Felicitas and the legend reads something like: "SALUIS AUGG ET CHESS FEL RART" but my book gives no translation of this! Value in VF is given as £22 but in this condition probably only a few pounds.

I read IMP MAXIMIANVS PF AVG - this is indeed Maximian. Here's the reference listing for the type:

Maximianus AE Follis of Carthage. AD 299-303. IMP MAXIMIANVS PF AVG, laureate head right / SALVIS AVGG ET CAESS FEL KART, Carthage standing front, looking left with fruits in both hands. Mintmark B. Cohen 510; RIC VI Carthage 31b; Sear 13306.

The reverse means, roughly, 'The emperors' safety makes Carthage happy'. This type was minted in Carthage in North Africa and made it all the way to North Yorkshire - quite a journey.

I agree, though it is difficult to distinguish between RIC 27b which has a smaller portrait and 31b which has a larger portrait.