If you are using the Mozilla Firefox browser, there are a few settings you can change so that e-books display properly within your browser.
In Firefox go to: Tools > Options
In the window that pops up, choose the ‘Application’ tab and change ALL FOUR Adobe Acrobat settings in the Content Type list to:
“Use Adobe Acrobat (in Firefox)”
You may also need to change the settings in Adobe Acrobat Reader.
In ADOBE READER Go To:
Edit > Preferences > Internet
From there make sure that the ‘Display PDF in browser’ check box has been ticked.
After doing this, PDFs should open within the browser if you are using Firefox.