Set up the space

background colour
dimensions

concept of a point - arbitrarily small radius - to point of vanishing

blow up space 

however close or far away we are, the point is always the same degree of specificity - is at a precise location

bring this out by introducing the 'stretchfactor', and zooming in and out
"makes point bigger", but need to compensate for this

need some suggestion of scale - venture to do this with a nested collection of circles

now introduce a 'vector' as a line (with arrow) pointing to whatever point you select with the mouse

to give idea of non-numerical scale, can now base scale on vector defined by selection

also useful to associate the contours ( = scaling circLes) and labels with the vector PQ 

2 thoughts about extension here:

	Need to get a different vector in the picture - so can consider scalar mults of PQ (e.g.)

	Also desirable to normalise the ccoordinate system so that the label of the  scaling circles is 1,2,3 etc

Can also reparametrise so that the direction of the vector is independent of its position (key abstraction that characterises vectors)

