Map data only returning 0

Hi all,
I am attempting to make a wireframe maze game - you know the type, the really early days of games early Ultima and Wizardry type... I (think I) have set everything up (its still in its very early days!) but when I test the maze data, all I seem to return are Zeros. So it doesnt appear to be reading the maze data correctly. This is my 1st crack at getting into data statements, so I still dont fully understand how they work, but with Krylars book and a bit of blood sweat and tears, I'm hoping to crack the nut in the next couple of days. Have a look at the code and see if you can see the (probably really simple) error I have made...

; Wireframe maze drawing program

Graphics 640,480
SetBuffer BackBuffer()

; declare the map variable
Map_Length=16
Map_Height=16
Dim maze(Map_Length,Map_Height)



While Not KeyHit(1)
	; clear the screen
	Cls
	DrawBox
	ReadMaze
	For i=0 To map_Length
		For j=0 To map_height
			Print maze(i,j)
		Next
		Next
	Flip
Wend
End

;******************************
;* Draws a box-like border    *
;* around the main maze       *
;* Player area                *
;******************************
Function DrawBox()
	Line 82,19,294,19
	Line 294,19,294,119
	Line 294,119,82,119
	Line 82,119,82,19
End Function

;******************************
;* Reads the data statements  *
;* to load the maze data      *
;* into the maze()() variable *
;******************************
Function ReadMaze()
	; Read (load) in the maze data into a variable
	Restore MazeData
	For y = 0 To Map_Height-1
		For x = 0 To Map_Length-1
			Read a	; get the map data and store into value
			maze(x,y) = a
		Next ; x
	Next ; y
End Function


.MazeData
Data 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1
Data 1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1
Data 1,0,1,0,1,1,1,0,1,0,1,0,1,1,0,1
Data 1,0,1,0,1,0,0,0,1,1,1,0,1,1,0,1
Data 1,0,1,0,0,0,1,0,0,0,1,0,0,1,0,1
Data 1,0,1,1,1,0,1,0,1,0,1,1,1,1,0,1
Data 1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1
Data 1,0,1,1,1,0,1,0,1,1,1,0,1,1,0,1
Data 1,0,1,0,0,0,1,1,0,0,1,0,1,1,0,1
Data 1,0,1,0,1,0,1,1,1,1,1,0,1,1,0,1
Data 1,0,1,0,1,0,0,0,0,0,0,0,0,0,0,1
Data 1,0,1,1,1,0,1,0,1,0,1,1,1,1,0,1
Data 1,0,0,0,1,0,1,0,1,0,0,0,0,1,0,1
Data 1,0,1,1,1,0,1,1,1,1,1,1,1,1,0,1
Data 1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1
Data 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1