获取错误调用未定义的函数模型()当我在CI框架中加载到控制器时

I just now learning codeigniter and this is my

model second_con.php

class second_con extends CI_Model 
{  //CI version 3.0

public function second_mod() 
{

    $query = $this->db->query('SELECT * FROM subdepartment');

    if($query->num_rows() > 0) 
    {

        foreach($query->result() as $rows)
        {
             $datas[]  = $rows;
        }
        return $datas;
    }
   }
   }

controllers second.php

class second extends CI_Controller {  

public function index() {

    $this->load-model('second_con'); //line 7

    $this->load->view('home1');
}
}

after this when I try to view this page. It showing error as follows. anyone can find out where I made mistake?

A PHP Error was encountered

Severity: Error

Message: Call to undefined function model()

Filename: controllers/second.php

Line Number: 7

Backtrace:

You are missing > in here load-model

This should be

$this->load-model('second_con'); # wrong

change to this

$this->load->model('second_con'); # correct