When the mouse cursor indicates multidirectional arrows,just
keep the left button pushed and drag it in any direction.
If you place the mouse cursor in the center of the image, it
becomes a magnifying glass.
Zooming: Keep the left button pushed and drag the mouse
upwards Distant viewing: Keep the left
button pushed and drag the mouse downwards
,just
keep the left button pushed and drag it in any direction.
.
