GENERAL EXCITING CAUSES 



41 



In this district I account for the preponderance of 

 cases after noon by attributing it to the long stretch of 

 work without food, and the ravenous feeding on bulky, in- 

 digestible material immediately afterwards. I have also 

 noticed that the great bulk of the cases occurring in the 

 early morning — say from 4 or 5 a.m. until noon — are 

 those that turn out to be fatal. 



Other and Various Exciting Causes of Colic. 

 — Ingestion of food contaminated with sand or gravelly 

 material, or containing substances (scraps of iron, wire 

 nails, etc.) likely to form nuclei of calculi. Catarrh 

 of the intestines often accompanies influenza and many 

 respiratory affections, and animals convalescent from 

 these maladies have a weakened digestive tube, and are 

 prone to constipation and impaction. Aneurism of the 

 anterior mesenteric artery, due to the presence of 

 strongyles, frequently determines the impaction of faeces, 

 owing to the interference with the blood-supply to the 

 caecum and colon. Pieces of the thrombus break off, 

 and effectually plug smaller arteries supplying, mainly, 

 parts of the caecum and colon. In the anaemic area 

 of bowel thus produced peristalsis is diminished, or 

 perhaps altogether in abeyance. As a consequence we 

 get great weakness, or even paralysis, of that portion 

 of the bowel, with a tendency to stasis of its contents, 

 and obstruction from faecal accumulations. Other factors 

 that, directly or indirectly, tend to produce constipation 



