Another Variation ! :-

I have drunk one and I will drink two
There's a man who'll drink twice as much as you
'Cos he's been and done what the rest have done
Him and his Good Companions

I have drunk two and I will drink three
Here stands a man who'll drink twice as much as me

I have drunk three and I will drink four
Here comes a man who can double the score

I have drunk four and I will drink five
Heres a man who'll drink with any man alive

I have drunk five amnd I will drink six
Here's a man in a hell of a fix

I have drunk six and I will drink seven
Here's a man who'll drink with all the saints in heaven

I have drunk seven and I will drink eight
Here'a a man in a hell of a state