HYGIENIC REMARKS. 185 



others, when compared with the blood which entered it. But 

 the losses and gains in particular parts of the body are in 

 such small proportion as, with the exception of the blood 

 gases, to elude analysis for the most part; and, the blood 

 from all parts being mixed up in the heart, they balance one 

 another and produce a tolerably constant average. In 

 health, however, the red corpuscles are present in greater 

 proportion to the plasrmi after a meal than before it. 

 Healthy sleep in proper amount also increases the proportion 

 of red corpuscles, and want of it diminishes their number, 

 as may be recognized in the pallid aspect of a person who 

 has lost several night's rest. Fresh air and plenty of it 

 favors their increase. The proportion of these corpuscles has 

 a great importance, since they serve to carry oxygen, which 

 is necessary for the performance of its functions, all over 

 the body. Ancemia is a diseased condition characterised 

 by pallor due to deficiency of red blood-corpuscles, and ac-1 

 companied by languor and listlessness. It is not unfrequent 

 in young girls on the verge of womanhood, and in persons 

 overworked and confined within doors. In such cases the 

 best remedies are open-air exercise and good food, though \ 

 medicines containing iron are often of great use. 



The Quantity of Blood in the Body. The total" weight 

 of the blood is about one-thirteenth of that of the whole 



What would we find on comparing the blood leaving an organ 

 with that which entered it? What losses and gains are most easily 

 detected? How is it that the blood maintains a tolerably uniform 

 average composition ? How does a meal affect the proportion of red 

 corpuscles? How does sleep ? Illustrate. What is the influence of 

 plenty of fresh air ? Why is the proportion of blood-corpuscles im- 

 portant ? What is anaemia ? What class of persons is apt to suffer 

 from it ? What are the best remedies for it ? 



What is the proportion of the weight of blood to that of the 

 whole body? 



