NATURAL THEOLOGY. 201 



the heart pumping at the centre, at the rate of 

 eighty strokes in a minute; one set of pipes carry- 

 ing the stream away from it, another set bringing, 

 in its course, the fluid back to it again ; the lungs 

 performing their elaborate office, viz., distending 

 and contracting their many thousand vesicles by a 

 reciprocation which cannot cease for a minute ; 

 the stomach 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 pursuing 

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

 parotid, with many other known and distinguish- 

 able 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 within us at 

 one and the same time. Think of this ; and then 

 observe how the body itself, the case which holds 

 this machinery, is rolled, and jolted, and tossed 

 about, the mechanism remaining unhurt, and with 

 very little molestation even of its nicest motions. 

 Observe a rope-dancer, a tumbler, or a monkey ; 

 the sudden inversions and contortions which the in- 

 ternal parts sustain by the postures into which their 

 bodies are thrown; or rather observe the shocks 

 which these parts, even in ordinary subjects, some- 

 times receive from falls and bruises, or by abrupt 

 jerks and twists, without sensible or with soon- 

 recovered damage. Observe this, and then reflect 



