Which game is this: you are in the gargoyle garden

What is the text adventure being played in this photograph?

?

The computer is a HP 2647A Graphics Terminal, and the text visible on screen is:

 of the road is a 500 foot sheer cliff,over looking the sea shore. The
 road ends here but the wall continues west into the dense forest.

>ENTER GATE

 You are in the gargoyle garden.

 There is a way to go north

>GO DOWN PATH

 My input vocabulary doesn't include the word PATH

>LOOK

 You are in the gargoyle garden.

 There is a way to go west

 High hedges block the view around you but you can see some of the
 gargoyles along the roof of the mansion. There are paths going in several
 directions.

>_