ADVANCED EXPERIMENTAL PHYSIOLOGY 179 



constant, whatever quantity of food is present. When the whole 

 of the meal has been taken, the outline of the stomach should be 

 marked on the screen, together with the position of the umbilicus. 

 The greater curvature 

 generally reaches a short 

 distance below the level 

 of the umbilicus. The 

 main part of the stomach 

 is almost vertical, and is 

 situated to the left of the 

 middle line. The pyloric 

 end, however, passes up- 

 wards and to the right 

 across the middle line 

 (Fig. 166). The upper 

 limit of the gastric con- 

 tents is situated about 

 1J inches below the dia- 

 phragm, and is bounded 

 by a horizontal line, 

 above which is the gas- 

 containing fundus. 



On voluntarily con- 

 tracting the abdominal 

 muscles the lower border 

 of the stomach is raised 

 several inches, and on 

 relaxing them it gener- 

 ally drops an inch or 

 two. 



The peristaltic waves 

 can be seen passing from 

 the centre of the greater 

 curvature towards the 

 pylorus. They can, how- 

 ever, be more conveni- 

 ently studied in the 

 horizontal position. 



The examination 

 should be continued in 

 the horizontal position. 

 The greater curvature is 

 now seen to have risen 

 above the umbilicus, and 

 the clear area in the 



fundus is no longer visible (Fig. 167), the gas having moved to the 

 most superficial part of the stomach, corresponding with which a 

 resonant area can be marked out by percussion below and to the 

 left of the area of cardiac dulness. 



