RESPIRATION, CIRCULATION, DIGESTION, DIAGRAM 1. 11 



ORGANS OF BESPIEATION, CIECULATIOlNr 

 OF THE BLOOD, DIGESTION DIAGKAM 1. 



GENEEAL OBSEEVATIONS. 



The neck. The neck contains the larynx which communicates 

 with the throat above, and joins the wind-pipe below, which 

 conducts air to the lungs. 



The larynx makes a projection in man, which is felt in the 

 neck, and is called Adam's apple. When the larynx is stopped 

 up, suffocation ensues, which is what happens in the croup of 

 children. The surface of the larynx is exceedingly sensitive ; 

 and if it is touched by anything but air, a violent fit of coughing 

 is the result. This happens when we swallow anything the 

 wrong way, that is when a drop of water or a morse] of food 

 penetrates into the larynx, instead of falling into the oesophagus 

 behind the larynx* 



Below the larynx, near the wind pipe, is a gland called the 

 thyroid gland. It is not usually felt under the skin, and we only 

 mention'it because it produces goitre, when it swells to a large size. 

 Goitre is very common in some countries, and seems to be con- 

 nected with bad water. 



The chest. The chest is protected in front by the ribs, and is 

 separated below from the abdomen by a partition called the 

 diaphragm. The chest contains the oesophagus and the wind- 

 pipe at the back; the heart in front, and the lungs on each side. 

 The heart is not situated wholly on the left side, as is often 

 supposed ; the point only is a little inclined to this side ; and as 



