Load Js Files And Create Instances Dynamically?

I'm trying to create a function to load a js file and instance a object.

I'm trying something like this:

Code:
function Load(element)
{
var e = document.createElement("script");
e.type = "text/javascript";

[Code]....

I'm creating the files with the same name as the object. I'm trying to load a file/object name Manager. It's loading the js file, but it says that the object does not exits.

What's the best way to load a js file and create the instance of the object dynamically?