128 LETTERS TO BROTHER JOHN. 



the honey-comb ; that is, the body. Having done 

 this, they take wing once more ; and returning in 

 the same direction, but by different routes (the 

 veins), they re-enter the garden-gate (the heart), 

 and again settle themselves down upon the flower- 

 bed (the lungs), in order to collect a fresh supply 

 of honey ; that is, of nutritive properties. Observe : 

 a stream of arterial blood is a bee laden with 

 honey ; a stream of venous blood, a bee despoiled 

 of its honey. 



Now, if, as I hope, you have understood my for- 

 mer Letters, you will recollect that the old body is 

 constantly being dissolved, and carried away, and 

 emptied into the venous blood, by the lymphatic 

 absorbents ; and that the new materials afforded by 

 new food are also emptied into the venous blood 

 at the same place (viz. just before it enters the 

 right side of the heart, on its way to the lungs), by 

 the lacteal absorbents. The black blood, therefore, 

 when it reaches the lungs, has mixed up with it 

 a portion of the old body in a fluid state, called 

 " lymph," and also a certain quantity of fresh nutri- 

 ment, also in a fluid state, called " chyle." But the 

 fresh nutriment (that is, the chyle) has not yet 

 become blood : it is merely mechanically commingled 

 with the blood. The effect, therefore, which the 



