rain

As I sat here at my computer browsing around myspace, facebook, and uploading some pictures that I took over the weekend, a familiar smell entered the room through a nearby window. I didn't have to look out the window to figure out what odor was coming through the window. As soon as the distinctive smell entered my nostrils I knew that it was the smell of rain. Sure enough, when I glanced at the window from my seat at the computer dozens of rain droplets were hitting the glass through the screen.
What actually makes the rain smell like it does? Rain is just water, right? Water fron the sink doesn't have a smell. So what makes rain smell? Wow I never really thought of that until now..I always thought rain smelt like how it does because it's rain.
Perhaps for my nature essay I could write something about rain...