That is about the general description you will get when you ask any Jamaican over 50 about rolling calf.  Despite their seeming confidence, if you observe carefully, there might be a fleeting sense of fear before they utter “Nutten doan go so ... rolling calf is not real.” 

Now whether rolling calf is real or not, I don’t know, because mi never see any yet.  Nor have half of those who claim to have seen one. It is like the proverbial 'fish that got away.'  All you know is that it is somethingsomethng to betotally feared, wuss dan how yuh friad of duppy.

The truth be told, the poor rolling calf was probably a cow that got away and could be seen walking in the bush late at night. Now between me and yuh, if you were to buck up a big ol cow in the darkness late one night, see the glint of his big ol eyes, and hear the famous  chain dragging, yuh wouldn't run and bawl out to? And while you are running, mind yuh trip over the chain. – the same chain which his owners thought was too strong for him to dislodge so he could move from where he was tethered. 

But there are two other parts to the story : the effect that seeing a rolling calf has on you and then  what you supposed to do if you see one. Seeing a rolling calf is supposed to make yuh head well big big and feel light.  Yuh tongue supposed to get heavy and lay dung inna di bottom of yuh mouth, yuh eyes supposed to pulp out of yuh head, yuh foot dem can't move. In essence you are rendered immobile and speechless.

An what can you do? First off when yuh start to feel yuh head get light and start to swell, that mean that you and the rolling calf about to buck up, i.e.  come face to face. But dem say rolling calf fraid a badwud, so if yuh start to light up the place wid some good ol Jamaican expletives, and wuss if yuh have a machete, or a piece of ol iron, start slapping it against any  piece of furniture or large object, to make a lot of noise.

Obviously, the rolling calf is a quiet soul who cannot tek di noise and di badwud dem, because that is supposed to make him retreat, with his chain making less noise that the noise you create.

                   So mi buy it... so mi sell it. So mi get it... so mi gi it to yuh