We have always called this bush-tree a Moc Orange. Love the flowers on it. Richard brought me in some today because they don't last long and he knows I love the smell of them. And Sheila if you read this the beautiful Doily you made me is in the picture.
Yes, Nancy the white flowers are Philadelphus coronarius aka Mock Orange. My grandparents had a bush next to the garage when I was growing up. The smell was heavenly when it bloomed! Enjoy them while you can!