ABNORMAL CONDITIONS OF THE BLOOD. 63 



dition is produced by transfusing the serum of the same species, whereby, at the 

 same time, the urea is increased. Injection of egg-albumin produces albuminuria 

 (Stokes, Lehmann). 



(B.) Diminution of the Quantity of Blood, or its Individual Consti- 

 tuents. (1.) Oligsemia vera, or diminution of the quantity of blood as a whole, 

 occurs whenever there is haemorrhage. Life is endangered in newly-born children 

 when they lose a few ounces of blood; in children a year old, on losing half-a-pound ; 

 and in adults, when one-half of the total blood is lost. Women bear loss of blood 

 much better than men. The periodical formation of blood after each menstruation 

 seems to enable blood to b-j renewed more rapidly in their case. Stout persons, 

 old people, and children do not bear the loss of blood well. The more rapidly 

 blood is lost, the more dangerous it is. 



Symptoms Of LOSS Of Blood. Great loss of blood is accompanied by general 

 paleness and coldness of the cutaneous surface, increased oppression, twitching of 

 the eyeballs, noises in the ears and vertigo, loss of voice, great breathlessness, 

 stoppage of secretions, coma ; dilatation of the pupils, involuntary evacuations of 

 urine and faeces, and lastly, general convulsions, are sure signs of death by 

 haemorrhage. In the gravest cases restitution is only possible by means of trans- 

 fusion. Animals can bear the loss of one-fourth of their entire blood without the 

 blood-pressure in the arteries permanently falling, because the blood-vessels con- 

 tract and accommodate themselves to the smaller quantity of blood (in consequence 

 of the stimulation of the vasomotor centre in the medulla). The loss of one-third 

 of the total blood diminishes the blood-pressure considerably (one-fourth in the 

 carotid of the dog). If the haemorrhage is not such as to cause death, the fluid 

 part of the blood and the dissolved salts are restored by absorption from the 

 tissues, the blood-pressure gradually rises, and then the albumin is restored, 

 though a longer time is required for the formation of red corpuscles. At first, 

 therefore, the blood is abnormally rich in water (hydrcemia), and at last abnormally 

 poor in corpuscles (oligocythcemia, hypoglobulie). With the increased lymph- 

 stream which pours into the blood, the colourless corpuscles are considerably 

 increased above normal, and during the period of restitution fewer red corpuscles 

 seem tc be used up (e.g., for bile). 



After moderate bleeding from an artery in animals, Buiitzen observed that the 

 volume of the blood was restored in several hours; after more severe haemorrhage 

 in 24 to 48 hours. The red blood-corpuscles after a loss of blood equal to 

 I'l to 4'4 per cent, of the body-weight, are restored only after 7 to 34 days. 

 The generation begins after 24 hours. During the period of regeneration the 

 number of the smallest blood-corpuscles (haemato-blasts) is increased. Even hi 

 man the duration of the period of regeneration depends upon the amount of blood 

 lost (Lyon). The amount of haemoglobin is diminished nearly in proportion to 

 the amount of the haemorrhage (Bizzozero and Salvioli). 



Metabolism in Anaemia. The condition of the metabolism within the bodies of 

 anaemic persons is important. The decomposition of proteids is increased (the 

 same is the case in hunger), hence the excretion of urea is increased (Bauer, 

 Jurgensen). The decomposition of fats, on the contrary, is diminished, which 

 stands in relation with the diminution of 62 given off. Anaemic and chlorotic 

 persons put on fat easily. The fattening of cattle is aided by occasional bleedings 

 and by intercurrent periods of hunger (Aristotle). 



(2.) An excessive thickening of the blood through loss of water is called 

 Oligaemia sicca. This occurs in man after copious watery evacuations, as in 

 cholera, so that the thick tarry blood stagnates in the vessels. Perhaps a similar 

 condition though to a less degree may exist after very copious perspiration. 



(3.) If the proteids in blood be abnormally diminished the condition is called 

 Oligaemia hypalbuminosa ; they may be diminished about one-half. They 

 are usually replaced by an excess of water in the blood. Loss of albumin from 



