smith --irector of the smithson the warors talk about and constitution. tv.ook author heather cox on the history of the republican party. noon, a legaly at affairs editor and supreme court biographyer. historians and authors talk 100 yearsd war i, later. sunday afternoon, on american 100th anniversary of the panama canal. let us know what you think about the programs you're watching. call us. us at comments at tweet.org or send us a join the c-span conversation. like us on facebook. follow us on twitter. traveling to u.s. cities to history andtheir literary life. and this weekend, we partnered toh comcast for a visit boulder, colorado. >> so my book is called the beast in the garden, because a book about a large animal that in ancient times or in history we would have called a beast, a mountain lion, in what is really a garden, and that is boulder, colorado. boulder is a beautiful, seemingly natural place. in many ways, it has been altered by humankind. when you get this wild animal come nothing this artificial landscape, you actually can cause changes in