LETTERS TO BROTHER JOHN. 207 



physiology. Both fluids go by the general name of 

 blood; and this increases the difficulty, weakens the 

 distinction, and produces confusion in the mind. 

 It seems difficult to be understood how blood can, 

 at once, be the support of life, and yet destructive 

 to it. Blood is blood ; and people generally are 

 not aware that there are two sorts of blood in the 

 body. Blood is blood : true ; but arterial blood is 

 not venous blood ; and there is not more difference 

 between champagne and ditch-water, than between 

 these two kinds of blood : one nourishes the body ; 

 the other poisons it. 



One of the most common symptoms of the dis- 

 ordered condition of the body, now under conside- 

 ration, is the appearance of small, black, irregularly- 

 shaped specks, resembling little pieces of broken 

 cobweb, floating before the eyes. This arises from 

 congestion of venous blood in and about the nerve 

 of vision the optic nerve. This nerve is com- 

 pressed by the gorged veins entering into its own 

 structure, and also of the veins immediately sur- 

 rounding it. The energies of this nerve are par- 

 tially paralyzed by the debilitating and devitalizing 

 influence of the venous blood which has accumu- 

 lated within and around it. This nerve, too, like 

 every other part of the body, is in a state of per- 



