208 THE WONDERFUL HOUSE THAT JACK HAS 



we can realize the importance of the nervous sys- 

 tem and be very careful to protect it. Although nature 

 has strongly fortified the brain with the skull, and the 

 spinal cord with the backbone, yet we should take 

 especial care to guard these regions from injury. A 

 hard blow or a fall might cripple one for life. 



