[evacuationdrill]

I've always used alt+scroll for horizontal scrolling.

Edit: doesn't seem to work on the linked page

[onli]

Yep it doesn't. So actually, on chrome, without an autoscroll extension, there is no way to scroll that page (apart from the with the right cursor button, which is way to slow to actually be valid) on a normal desktop pc. Happy new world.

[graedus]

shift + mousewheel works for me in chrome (windows 7 and osx)

[bhandziuk]

you can click in the scroll bar. It is fast enough. Better than holding the right button.