122 LETTERS TO BROTHER JOHN. 



RESPIRATION, and SECRETION, in active operation, 

 by tracing a given portion of food through all the 

 changes wrought upon it, by virtue of these four 

 actions, until it has become assimilated to the body. 



First, let us trace the CIRCULATION OF THE 

 BLOOD. 



The blood, of a bright vermilion hue, and richly 

 laden with the elements of living matter the 

 new materials for repairing the wasted body 

 starting from the left side of the heart, enters the 

 aorta. From the aorta it is distributed into 

 branches of the aorta, and hence into branches of 

 these branches, being divided and subdivided into 

 smaller and smaller streamlets, as it proceeds from 

 branch to branch. In this manner it is propelled 

 onwards, until it has been subdivided into as many 

 minute hairlike streamlets as there are points in the 

 body ; there being no point of the body which is 

 not supplied and nourished by one of these scarcely 

 conceivable minute streamlets of blood. 



While these countless myriads of currents of 

 blood are thus traversing the body each, as it 

 were, intent on reaching some one particular point 

 or other as the end of its journey they may be 

 appropriately likened to an innumerable swarm of 

 bees ; each laden with stores, and hastening onward 



