running a script in a php module

I copied the code exactly.

$src = base_url("assets/themes/default/images/{$img}");
this is what is being generated:
<img src='http://localhost/assets/themes/default/images/Logo - Research Study Toolkit(3).jpg' style='float:left;margin-top:5px;z-index:5' alt='Logo'>

And here is the attempt to print it:
echo $img;

This does not give an error but the logo just shows up as a broken  "Logo". I think the problem is that path is wrong. I tried copying the path directly into the browser, but that also fails. Is there a better way to get the path to the file?

proof that an old dog can learn new tricks