@
kyteflyer - not sure how to do with mouse, but here's the keyboard way
see first item - 
http://manual.calibre-ebook.com/gui....oard-shortcuts 
In Windows & Linux (I think) - on the Read column cell for a book press 
F2, 
Y and 
Enter
In OS/X - on the Read column cell for a book press 
Enter, 
Y and 
Enter
BR