Trigger "Start Speaking" using AppleScript?

Hi, that’s pretty much it - is there a way I can trigger “Start Speaking” for the selected text in the frontmost window via AppleScript (in 10.8.x)? That is, the option normally available through the contextual menu under the Speech submenu? I can’t find anything obvious in any of the Dictionaries I looked through.

Model: iMac
Browser: Safari 537.71
Operating System: Mac OS X (10.8)