CHANGES IN THE BLOOD. 73 



by tliose in charge of horses who have a belief that it is a bad 

 thing to allow a horse to drink while out on a journey or in the 

 hunting-field. Small and repeated drinks are always beneficial, 

 and prevent much suffering. 



The alhuTnen of the blood may vary, consistently with health, 

 from 60 to 70 parts in 1000. Its amount, according to 

 Andral and Gavarret, is notably increased in various diseases ; 

 but this excess does not appear to be characteristic of any. In 

 acute rheumatism an increase was found varying from 4 to 24 ; 

 in pneumonia the highest increase was about 12 ; in pleurisy 

 the extraordinary amount of 34 in excess was once observed ; 

 and several other instances are mentioned of a lower degree. 

 Excess of albumen in the blood is witnessed in the horse in a dis- 

 ease which the late Mr. Haycock termed hysteria. — (See Azoturia 

 or Urccmic Paralysis.) Very probably the albumen in this disease 

 is not only excessive in quantity but deteriorated in quality. 



The albumen is defective in cases of albuminuria, in the 

 " rot " in sheep, and in dropsies, whether dependent on organic 

 disease of the heart, or on the presence of entozoa — distomata — 

 in the liver. It is a remarkable fact, recorded by Andral, Gavarret, 

 and Delafond, that in sheep affected wdth ansemia, with defi- 

 ciency of the red globules, but without dropsy or entozoa, there 

 was no deficiency in the albumen. Dr. Williams concludes from 

 this, that cachexia and anaemia attended by dropsy owe this con- 

 comitant to a w^ant of albumen in the blood ; and he seems to 

 be of opinion that a deficiency of the albumen, by destroying the 

 spissitude of the blood, and allowing it to transude through the 

 coats of the vessels, is a chief feature in the dropsical diathesis. 



The fibrin of the Mood. — When fresh drawn blood is left to 

 itself, it very soon coagulates or becomes solid, and the substance 

 thus becoming spontaneously solid is the fibrin, which, when 

 separated from the blood, is a tough, elastic, tolerably firm, 

 whitish-grey looking naaterial, insoluble in water. Under the 

 microscope the fibrin appears as a homogeneo-granular matter, 

 with a more or less marked tendency to fibrillate. The white 

 globules are usually seen imbedded in the mass, but they do not 

 appear to modify the character of healthy fibrin. This coagula- 

 tion is due to the formation of fibrin, a material which does not 

 exist in the blood circulating in healthy vessels, but is formed 

 in the blood and lymph when removed from the body. At first 



