THE SPLEEN. 193 



like the liver or sweetbread, each of which has a given 

 duty to perform in secreting a fluid (or fluids) from 

 the blood, and of giving forth such manufactured pro- 

 ducts to be used in the digestive process. But, while 

 there is an absence of apparent outlet, we are struck 

 by the fact that into the spleen a very large artery 

 passes, while out of it proceeds a very large vein. 

 . If, now, we subject the organ to a microscopic 

 scrutiny, we learn more in detail regarding its nature. 

 It is a soft pulpy organ, and its substance is appro- 

 priately enough known as " spleen pulp." This sub- 

 stance really consists of a kind of meshwork, supporting 

 the softer matter of the organ. Now, into this pulp 

 the artery of the spleen dives, dividing and branch- 

 ing, as it goes, into numberless minute blood-vessels. 

 Closely connected with this arterial network are the 

 beginnings of the splenic vein ; so that, practically, we 

 arrive at a first and important conclusion about the 

 spleen, when we discover that blood must perpetually 

 be whirled into the organ by the artery, and as con- 

 stantly taken away from it by the vein. 



We might, in truth, not inaptly compare the spleen 

 to a kind of whirlpool or eddy, on the course of a 

 river the blood-circulation into which the stream 

 is swept, and out of which it is in turn whirled away. 

 But the microscope teaches us something more about 

 the spleen-pulp and its nature. Borne on the little 

 twigs of the spleen artery we see certain rounded 

 bodies known as " spleen corpuscles." Moreover, im- 

 bedded in the pulp we find the corpuscles or globules 

 of the blood in all stages of breakdown and in all 

 stages of construction. So that a second conclusion 

 regarding the organ seems warranted namely, that 

 it is closely connected with the blood, and with the 



