The scale of a drawing on the screen can be changed by calling the Zoom Factor option from the View menu or the Toolbar item . The cursor is changed to a magnifying glass. To apply this, click the place where you want the centre of the enlarged or reduced drawing to be located. This will call up the Zoom dialog box.
You must nominate a magnification factor here. If this is below 1.0 the image is reduced by the ratio indicated; if it is greater than one it is enlarged by this ratio. The default value is 1.5
A wheel mouse can also be used to zoom in or out.