IN HYGIENIC PHYSIOLOGY. 171 



24. Why are students very liable to cold feet ? 



Because the tendency of the blood is toward the head, to 

 supply the waste in that part of the body. 



25. Is the proverb that " blood is thicker than water 7f 

 literally true ? 



(See DBAPEB'S Human Physiology, p. 112.) 



The specific gravity of the blood varies from 1.050 to 1.059. 



26. What is the effect upon the circulation of 6( holding 

 the breath"? 



The blood is not oxygenated, the products of waste accumu- 

 late in the system, the circulation is impeded, the blood-vessels 

 become distended, and are liable to burst, while all the delicate 

 organs, especially the brain, are oppressed by congestion. 



27. Which side of the heart is the stronger ? 



The left, which drives the blood to the extremities. 



28. Hoiv is the heart itself nourished? 



The coronary arteries springing from the aorta just after 

 its origin, carry blood to the muscular walls of the heart: the 

 venous blood comes back through the coronary veins, and 

 empties directly into the right auricle. 



29. Does any venous blood reach the heart without 

 coming through the venm cavce ? 



(See Question 28.) 



30. What would you do, in the absence of a surgeon, in 

 the case of a severe wound ? 



(See Physiology, pp. 128, 258.) 



31. What would you do in case of a fever ? 



(See Physiology, p. 263.) 



32. What is the most injurious effect of alcohol upon 



the blood ? 



(See Physiology, p. 144.) 



Its action upon the red corpuscles. 



33. Are our bodies the same from day to day ? 



No, they are constantly changing. 



