THE BREATHING OF THE BRAIN. 101 



they are expanded or enlarged when the lungs draw them out, of 

 course a physical fluid enters them to fill the space created, and tends 

 to fill the organs to which they are distributed. In this way the 

 nervous system, the focus of life, opens the frame at the same inter- 

 vals as the lungs, the circumference of life; the lungs being simply 

 the want of living fluid, and the nerves the corresponding supply. 

 This is an organic cooperation between effect and cause, whereby the 

 highest purposes of the organization are seconded most absolutely, 

 and yet most freely, by the lowest. 



The nerves then breathe their atmosphere, the nervous fluid, at 

 the same intervals as the lungs breathe theirs, which is the proper 

 atmospheric fluid, and the breath of the nerves is the life of the 

 lungs, as the breath of the lungs is the bodily action of the nerves. 

 The nerves, however, are continuous with the brain, and secondly, 

 we observe that their expansion is its expansion. It opens, for mo- 

 tion's purposes, into the chest, by the nerves, and by the spinal 

 marrow ; the lungs have their suckers upon it everywhere, through 

 the membranes and the blood-vessels. It, therefore, breathes under 

 the attractions of the pulmonic air-pump. Like every other part it 

 respires its own thoughts or objects. What these are, it does not 

 behove us to inquire, but we may affirm generally, that they are 

 those fluids which are the brains of the body and outward universe. 

 The lungs breathe that which answers to lungs in nature, namely, 

 the air. The heart breathes that which is the heart's in the system, 

 namely, the blood ; and each organ, as a rule, breathes its own cor- 

 responding fluids. 



The heart, as we have just anticipated, breathes also with the 

 lungs, and so manifestly, that physiology already contains many 

 chapters upon the influence of the respiration upon the circulation. 

 The pulmonary motions acting upon the heart and great vessels, 

 cause the venous blood to return to the heart, and somewhat retard 

 the outgoing arterial blood, during the inspirations; and vice versa; 

 and imprint upon the pulse at the fountain-head the force which is 

 destined to supplant the pulse where the vessels enter the organs. 

 By this means the ultimate intention is intimated from the begin- 

 ning; the blood in its childhood is let into the secret of its destiny; 

 and the sanguineous system is prepared at once for submission to 



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