PARTS OF ANIMALS, III. ix. 



kidneys, the trouble is not easily removed, because 

 it is as though the patient had many kidneys diseased 

 and not one only ; and so the cure is more difficult to 

 effect. 



The channel which runs from the Great Blood- 

 vessel to the kidneys does not debouch into the 

 hollow part of the kidneys, but the whole of what 

 it supplies is spent upon the body of the kidneys ; 

 thus no blood goes into the hollows, and at death 

 none congeals there. From the holloAv part of the 

 kidneys two sturdy channels " lead into the bladder, 

 one from each ; these contain no blood. Other 

 channels come from the Aorta to the kidneys ; 

 these are strong, continuous ones. This arrange- 

 ment is on purpose to enable the residue from the 

 moisture to pass out of the blood-vessel into the 

 kidneys, and so that when the fluid percolates 

 through the body of the kidneys the excretion that 

 results may collect into the middle of the kidneys, 

 where the holloAV is in most cases. (This explains, 

 incidentally, why the kidney is the most ill-scented 

 of all the viscera.) From the middle of the kidney 

 the fluid is passed off through the aforesaid channels 

 into the bladder ; by which time it has practically 

 taken on the character of excremental residue. The 

 bladder is actually moored to the kidneys : as has 

 been stated, there are strong channels extending 

 from them to it. 



We have now given the causes for Avhich the 

 kidneys exist, as well as their character and functions. 



The right kidney is always higher up than the left. 

 The reason for this is that as motion always begins on 

 the right-hand side, the parts that are on that side are 

 stronger than those on the other ; and owing to this 



273 



