What you need to do is assign the image a class (or even better an ID), then in your CSS specify the initial height and width.
Then an onMouseOut event that'll change the size back to normal.What is the code ';html coding'; for point picture to view the bigger size?
In dreamweaver create a layer and insert your big image. Make your small image a link so that when you place the mouse on it the layer with the big image shows and on mouseout the layer hides.
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