'Magic' mouse does not scroll

This so-called 'magic' mouse came with my iMac. It simply does not work; I've followed every piece of advice & guidance - have gone into the settings & ticked all the relevant functions - but the 'scroll' function does not exist. I roll my finger down the mouse, exactly as in the guidance illustrations - and absolutely nothing happens. All this does is bring up a scroll bar on the right-hand side, so I then have to move over & use the scroll bar - something I've not had to do for years with my Windows PC & wireless mouse with a wheel. Is this seriously how this mouse is meant to work? I.e. it simply activates a 1990's style scroll bar?! If so I think this is a bit of a cheek; Macs are not cheap; they could at least have supplied it with a proper functioning mouse. Especially given that it also comes with tiny stunted keypad with some crucial functions missing. I will now have to replace both of these - at additional expense!