SOS 



large animals, by confining the sources of life in them 

 within a narrow circle, has secured them from harm by 

 many advantages. Compare the result of the motions 

 or actions oi a sea-worm with thai of the motions or 

 actions of an ape, and you will soon perceive which of 

 these animals has been most favoured. 



Finally, organized bodies, to which a power has been 

 granted of multiplying by a method which seems to 

 tend to their destruction, are such as are exposed to tlie 

 greatest dangers, ancf whose life is necessarily threatened 

 every moment with a thousand various accidents. 



19. Amongst the motions we observe in the animal 

 machines, that of the circulation holds the first rank, 

 either by its importance, or its nature, duration, and 

 the number of organs by me-an^ whereof it is performed. 

 There i in $ his juotion an ail of grandeur that seizes 

 fornU) i;u thi:rna.d, <i; -d which, by making it sensible 

 & the narrow 11s., .is *; i.nman understanding, penetrates 

 it with the laosi ^n-buiid respect, and fills it with the 

 highest admiration of the INFINITE MIND which, 

 illustriously shi'nes in the DIVINE AUTHOR of it, 



In the centre of the breast, between two spongy 

 masses known by the name of lungs, is deposited a 

 fleshy pyramid, whose base bears two small funnels like 

 ear-rings, which communicate with iv.o cavities con- 

 tained iu the inside of the pyiamid, and which divide it 

 according to Us k-ngth into two chambers or vejitricks, 

 the right ventricle a -<d the left. This pyramid is the 

 heart) the main spring of the machine. It has two 

 principal orders of muscular Jilre^ some of which pass 

 obliquely from the base to the point, others cut the lat* 

 ter transversely, From the exercise of these fibres two 

 opposite motions result ; one of dilatation, the other of 

 contraction, The heart seems to execute these motions 

 by turning on itself like a screw. Its point moves to- 

 wards or from the base, by rising or falling obliquely. 



Two great vessels, viz. an artery and a vein, communi- 



