mouse wheel produces special events like @code{wheel-up} and
@code{wheel-down}. (Some older systems report them as @code{mouse-4}
and @code{mouse-5}.) If the mouse has a horizontal scroll wheel, it
-produces @code{wheel-left} and @code{wheel-right} events as well..
+produces @code{wheel-left} and @code{wheel-right} events as well.
@vindex mouse-wheel-scroll-amount-horizontal
Emacs also supports horizontal scrolling with the @key{Shift}