LETTERS TO BROTHER JOHN. 105 



food, unless well supplied with blood by the heart. 

 If the brain die, the heart must cease to pulsate ; 

 and if the heart cease to move, the brain must 

 necessarily perish. It is not, then, by any means sur- 

 prising that an injury to one organ should be felt by 

 another ; on the contrary, it would be very won- 

 derful if it were not so. Accordingly, we see that a 

 wound of the foot will often produce locked-jaw ; 

 the disease, in this instance, being at one extremity 

 of the body, while the wound that produced it was 

 inflicted on the other. If it were necessary to 

 make this mutual dependence of all the organs on 

 each other still clearer, we have only to recollect, 

 that it is impossible to injure any one wheel of a 

 watch without injury to the whole machine with- 

 out incapacitating it properly to fulfil the office for 

 which it was intended. And man, the master- 

 miracle of nature, is a machine of far more delicate 

 and complicated structure than a watch, and there- 

 fore more readily deranged. 



Now, if no organ concerned in the preservation 

 of health (for it is of these I am speaking the 

 organs of nutrition) can be disordered without dis- 

 ordering all the others, how much more certainly 

 (if this were possible) will it be the case, when the 

 stomach, one of the most important of these organs, 



