130 NATURAL THEOLOaY. 



ceive how the same quantity of blood should be pushed 

 through each artery ; yet the result is right : the two limbs 

 which are nourished by them perceive no difference of sup- 

 ply — no effects of excess or deficiency. 



Concerning the difference of manner in which the sub- 

 clavian and carotid arteries, upon the different sides of the 

 body, separate themselves from the aorta, Cheselden seems 

 to have thought, that the advantage wliich the left gain by 

 going off at an angle much more acute than the right, is 

 made up to the right by their going off together in one 

 branch.* It is very possible that this may be the compen- 

 sating contrivance ; and if it be so, how curious — how hy- 

 drostatical I 



II. Another perfection of the animal mass is the 'pack- 

 age. I know nothing which is so surprising. Examine the 

 contents of the trunk of any large animal. Take notice 

 how soft, how tender, how intricate they are ; how constant- 

 ly in action, how necessary to life ! Keflect upon the dan- 

 ger of any injury to their substance, any derangement to 

 their position, any obstruction to their office. Observe the 

 heart pumping at the centre, at the rate of eighty strokes in 

 a minute ; one set of pipes carrying the stream away from 

 it, another set bringing, in its course, the fluid back to it 

 again ; the lungs performing their elaborate office, namely, 

 distending and contracting their many thousand vesicles by 

 a reciprocation which cannot cease for a minute ; the stom- 

 ach exercising its powerful chemistry; the bowels silently 

 propelling the changed aliment — collecting from it, as it 

 proceeds, and transmitting to the blood an incessant supply 

 of prepared and assimilated nourishment ; that blood pur- 

 suing its course ; the liver, the kidneys, the pancreas, the 

 parotid, with many other known and distinguishable glands, 

 drawing off from it, all the while, their proper secretions. 

 These several operations, together with others more subtile 

 but less capable of being investigated, are going on witliin 

 * Ches. Anat., p. 184, ed. 7. 



