function validate_addition_form() {
  if(document.getElementById("Title").value.length == 0) {
    alert("You must specify a title.")
    return false
  } else if(document.getElementById("URL").value.length == 0) {
    alert("You must specify a URL.")
    return false
  } else {
    var url = document.getElementById("URL").value

    if(url.indexOf(":") == -1) {
      alert("The URL is invalid -- please supply a valid URL.")
      return false
    }
  }

  return true
}