Confusion !

Recently I read the book Bharata Natyam by Sunil Kothari.
This is a book which tells us abt the various aspects of Bharatanatyam. Right from its Origin as in ancient times, spiritual background, technicalities and also the well-known dances all over the world. The good thing about this book is that it provides everything in detail with pictures and notations as well. From my side its a great research work. It was first published in 1979 and later repriented with revised edition in 1982. Obviously as I read the reprinted edition, I Suppose they must have made remarkable changes and must have truly done a good job and thus it was reprinted. But here one think is craving my mind from long time though I have read the book long time back. The word "BHARATANATYAM" written as Bharata Natyam ...with space between the two words. I really didnt get the idea behind dividing the word into Two? Is it a Mistake or is the writter trying to convey anythng from it? Or then its truly seems to be a silly mistake which have not been changed even after revision.
I hope if the third revised book atleast comes up with BHARATANATYAM !!!