Nearly 150 years ago, scientists began to imagine how information might flow through the brain based on the shapes of neurons ...

It will just become blurry. The resolution of a light microscope is around 0.2 μm, or 200 nm. This means that it cannot distinguish two points closer than 200 nm. One nm, or nanometre ...

You should not look through the microscope to do this ... if you can see it – is in the centre of the stage, where the light passes through. Focus the slide away from you by turning the coarse ...