There doesn't seem to be any buttons on the interface to zoom, and there's no keyboard buttons to zoom, and I checked in the Manual and there was nothing about Zoom... well to be exact, it says "If your mouse has a scroll-wheel- blah blah blah" and then moves on to the next chapter without then presenting any alternative to "If your mouse has a scroll-wheel."
I feel quite glum.
I feel quite glum.