INDIGESTION, OR DYSPEPSIA, 355 



of looking whenever he liked into the interior of a healthy man's stomach, and 

 watching the process of digestion. This privilege was obtained by what must be 

 regarded, from a medical point of view, as a happy accident. It appears that a 

 young Canadian, Alexis St. Martin, had a portion of the skin, muscles, and ribs of 

 the left side of his body blown away in a gun-shot wound, which laid open the 

 stomach also. He recovered from the frightful injury, but with an open wound in 

 the side which led directly into the stomach. The opportunity was taken, with the 

 patient's consent, of instituting a number of experiments on the process of digestion, 

 Different articles of food were eaten by St. Martin, and the action of the gastric 

 juice upon them in the stomach was carefully watched. It is difficult to over- 

 estimate the value of the information so obtained. In fact, it is to these observations 

 that we owe much of our knowledge respecting the relative digestibility of different 

 articles of food. It was found that beef was more readily digested than mutton, 

 and mutton more readily than either pork or veal. Among the substances most 

 quickly digested were rice and tripe, both of which disappeared in an hour. Fowls 

 are far from possessing the digestibility usually attributed to them, but turkey is of 

 all kinds of flesh, except venison, the most readily disposed of. 



There are certain substances upon which the gastric juice exerts no action, and 

 it should be remembered that whatever goes through the stomach untouched, passes 

 undissolved through the whole of the alimentary canal, and appears in the motions 

 unchanged. The frequency with which such substances as dried currants and 

 apple-pips are passed unaltered is familiar enough to all. Indigestible substances, 

 instead of being at once excreted, are occasionally retained in the stomach, causing 

 pain, indigestion, and irritation for days and days together. 



There are many circumstances, besides the nature of the food, which exert an 

 influence on the process of digestion. First and foremost among these is the 

 quantity of food taken ; for the efficient performance of digestion the stomach should 

 be fairly filled, but not distended. Dr. Beaumont's experiments showed that a 

 certain bulk was necessary for the performance of healthy digestion. This fact has 

 long been known by practical experience to uncivilised nations. Thus the Kams- 

 chatdales are in the habit of mixing earth or saw-dust with the train oil on which 

 alone they are frequently reduced to live, and the Yeddahs, or wild hunters of 

 Ceylon, on the same principle mingle the pounded fibre of soft and decayed wood 

 with the honey on which they feed when meat is not procurable. The time which 

 has elapsed since the last meal was taken should, for the effectual performance of 

 digestion, be sufficient to ensure the stomach being quite clear of food. The amount 

 of exercise taken previous and subsequent to the meal is not without its influence, 

 gentle exercise being favourable, and over-exertion injurious, to digestion. Then there 

 is the state of mind, tranquillity of temper being apparently essential to quick and 

 easy digestion. In addition may be mentioned the state of bodily health, and the 

 state of the weather. 



This naturaiiy brings us to the consideration of the causes of dyspepsia. These 

 will probably have been in & measure anticipated from what we have said con- 

 cerning the normal process of digestion. There is no more frequent cause of 

 dyspepsia than an excessive consumption of food. Over-eating, whether it consists 



