Fwd: Is it possible to choose rotational direction of vertical script if I want to force them to display horizontally?

For instance, traditional Mongolian script write in vertical-lr mode (text
run vertically from top to bottom, first line start on left), if you use
css writing mode horizontal-tb (default) then you can force it horizontal
by rotating each line of the text by 90 degree anticlockwise, and the
resultant text would be ltr. However, I just read on a Chinese webpage
http://www.zhihu.com/question/30727581 which claim there're a "traditional
way" of writing Mongolian horizontally by rotating it 90 degree clockwise
(despite I am not sure about what kind of tradition the webpage is
referring to nor do i know is it legit.), is this achievable via css?
[The message is a repost from unicode mailing list as I have been pointed
out that the message suit this list better.]