Error connecting to Database via class

[eluser]macleodjb[/eluser]
now i get this error

Code:

A PHP Error was encountered

Severity: Notice

Message: Undefined property: Joes_class::$db

Filename: libraries/Joes_class.php

Line Number: 8

This is what's inside my class

Code:

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');


class Joes_class {
    
    function get_industry() {
    $industry = "select * from industry where parentid = 0";
    $result = $this->db->query($industry);
    return $result;
    }



}?>

This is whats in my controller

Code:

class Register extends Controller {

    function Register()
    {
        parent::Controller();
        $this->load->database('default');
        $this->load->library('Joes_class');            
    }
    
    function index()
    {
        $data['page_title'] = "";
        $data['page_desc'] = "";
        $data['page_keywords'] = "";
        
        $this->load->view('account/register_form', $data);
        
    }
}

and this is how i am using it in my view page.

Code:

$industry_names = $this->joes_class->get_industry();