How Do You Age A Photo?

My project for class is the creation of a digital presence for Mary Anna Randolph Custis Lee the wife of Robert E. Lee and the great granddaughter of Martha Washington. I have created a blog where I write as Mary about her life right before the Civil War starts and as the Civil War gets underway. As part of this project I got all dressed up and went into DC to take photos by buildings that were built or being built when the Lee’s lived at Arlington House. I now have 50 or so photos taken by buildings like the White House, the Washington Monuments, and the Smithsonian Castle. The problem I am having is that while I have made the photos black and white they still look very modern. The image to the left is a good example of what I am struggling with right now. I feel like the image doesn’t seem old. This may be because it isn’t old and there is nothing that can be done about that. I also wonder about the buildings that are in the picture that wouldn’t have been built by the time the Lee’s left Arlington.   So here are my questions: how can I age these photos and what do you think about the idea of modern life creeping into a blog that is based on history?  As far at the photos go I am working with a Mac in iPhoto and have made the photos black and white. I have looked at some of the fading but it seems like it only fades from the edges inward and that’s not what I want. I want these to look old but not like they were aged perfectly.  With the idea of modern life creeping into the blog I feel two ways.  One is that the blog is fictional so I feel like liberties can be taken with what is posted.  On the other hand if feels a bit odd having images that have cars in the background or an image of the entire Washington Monument in them.  If anyone has any ideas or suggestions send them my way. Thanks.