Tumblr is a free blogging service that encourages short posts consisting of pictures, quotations and other random thoughts. Tumblr displays several posts per page, but because of the brief length of most Tumblr posts, your visitors may find that they have to click the "Next" link frequently when reading your content. Add a short line of code to your Tumblr blog to enable auto scrolling. When readers reach the bottom of a page, new content loads automatically.
Click the gear-shaped "Preferences" icon in the upper right corner of your Tumblr blog.
Click the "Customize Your Blog" button.
Click the "Info" tab in the upper left corner of the window.
Click the "Description" field, and type the following code:
You may find it helpful to copy and paste the code to avoid typing mistakes.
Click the "Save + Close" button in the upper right corner of the page.