Here's a fairly authoritative site which is a few pages deep on Google. Seems to me to be the most complete rendering of the song: http://members.madasafish.com/~cj_whitehound/Fanfic/J-song/The_Wizard.htm

From that page, the song was written in 1955. Here are the lyrics as they give them, though there is some commentary that there are two versions of the ending. The origin of the 'alternate' ending(s) is not explained.

THE WIZARD

1st half, universally agreed on:

With pointed hat and nails like claws
And a terrible smile on his face,
The wizard sits behind locked doors
In his cell in a mountain place;
Around the walls of his magic den,
Laid out in endless line
Are books of spells for him to cast
And bottles of magic wine.

With horny hands he waves his wand
And scatters upon the fire
A powder which burns with ghostly light
As the flames rise even higher;
His lips recite a magic spell,
The flames dance on the walls,
And shadows deepen on his face
As on his knees he falls.

2nd half, Verse for Ages version:

As I turn the pages of the picture book,
The scenes change endlessly –
Kings and queens and palaces
And galleons on the sea;
But whenever I look at the picture book,
I linger at the place
Where the wizard sits behind locked doors
In his cell in a mountain place,

With books of spells for him to cast
And bottles of magic wine;
And all the time his wicked eyes
Are gazing into mine.

2nd half, Novello & Co. Ltd. version:

As I turn the page of the picture book,
The scenes change endlessly –
Kings and queens and palaces
And galleons on the sea;
But whenever I look at the picture book,
I linger at the place
Where the wizard sits in his mountain cell
With a terrible smile on his face,

And books of magic spells to cast
And bottles of magic wine;
And all the time his wicked eyes
Are gazing into mine.

The references above are to Verse for Ages by Colleen Thatcher & Bernie Morris (Bronwyn Editions, 2009), page 189 and the original sheet music printed by Novello & Company, Limited 1955