[Steely Tom]

OK, this can be settled by Google (as can so many things):

a historic vs. an historic from betterwritingskills.com

(steely)

[Pharmboy]

Thanks, Steely.

Everyone's right.

[dsc]

Mr Anemone I'll show you whether I'm on a wire or not. Give me the 'oop.
Mr Chigger What?
Mr Anemone Oh, I don't suppose we know what an 'oop is. I suppose pater thought they were a bit common, except on the bleedin' croquet lawn.
Mr Chigger Oh, a hoop.
Mr Anemone 'Oh an hoop.' (taking hoop) Thank you, your bleeding Highness. Now. Look. (he waves hoop over head and feet)
Mr Chigger Go on, right the way along.
Mr Anemone All right, all right, all right. (he moves hoop all the way along himself allowing the wire to pass through obvious gap in hoop's circumference). Now, where's the bleeding wire, then?
Mr Chigger That hoop's got a hole in.
Mr Anemone Oh Eton and Madgalene. The hoop has an hole in. Of course it's got a hole in, it wouldn't be a hoop otherwise, would it, mush!
Mr Chigger No, there's a gap in the middle, there.
Mr Anemone Oh, a gahp. A gahp in one's hhhhhoop. Pardon me, but I'm off to play the grand piano.

[HiTech RedNeck]

On Google, "a historic" will find things like

(A) Historic blah blah blah
(B) Current bleah bleah bleah

So the count may be somewhat biased.