THE GREAT SYMPATHETIC. 347 



be impaired. There does not seem to be any decisive proof that any of 

 the fibres of the sympathetic, properly speaking, are motor or sensory, or 

 that its ganglia produce reflex action, the agency which it exerts in these 

 respects on the muscular structure of the heart, blood-vessels, digestive 

 or urinary organs, being due to the associated cerebro-spinal fibres. 



In this manner, by its distribution to the arteries, the sympathetic, as 

 a compound nerve, exerts a power over the passage of the blood through 

 them by influencing their contractility, and thereby their diameter. In 

 virtue of this, it therefore affects the rapidity of secretion, and also regu- 

 lates the rate of nutrition. The entire digestive tract, with its dependen- 

 cies are thus brought under its influence, the salivary glands, pharynx, 

 oesophagus, stomach, intestine, nasal, bronchial, and pulmonary sur- 

 faces, etc. 



The view of the function of ganglia presented on preceding pages is 

 strongly supported by the mechanism and phenomena of the Itg an Ha are 

 sympathetic nerve. Its ganglia permit the influence passing reservoirs of 

 along the nervous cords to escape therefrom into new chan- ( 

 nels, and also retain and store up nervous power. They become, there- 

 fore, magazines of force, and are hence capable of sustaining rhythmic 

 movements. Even after organs have been exsected, they will still exhib- 

 it, under the influence of these ganglia, their accustomed motion, as is the 

 case with the heart, which, in some of the cold-blooded animals, will con- 

 tinue its contractions for many hours after it has been cut out of the body. 



I therefore regard the sympathetic system as having for one of it& 

 main functions the equalization or balancing of the nervous Conclusion 

 force, storing up all transient excesses of it, and furnishing f^Sn^ftiL 

 all transient deficiencies. As in a mechanical contrivance, sympathetic. 

 in which the prime mover works in an irregular way, the fly-wheel har- 

 monizes all such variations, storing up or supplying power as the cir- 

 cumstances may require, so does this complicated apparatus act in the 

 mechanism of innervation. And it is worthy of remark, that some such 

 arrangement would seem to be necessary, since the organs of digestion, to 

 which the sympathetic is so largely directed, are periodically in activity 

 and periodically quiescent. 



It is to be greatly regretted that the term sympathetic has been ap- 

 plied to this important nerve, since that term, as defining function, has 

 led to the promulgation of theoretical views which have exerted an influ- 

 ence to the disadvantage of the progress of physiology views which will 

 not bear the test of anatomical criticism, and which are therefore incor- 

 rect. It is always much better to give designations in allusion to struc- 

 ture or position than to function, especially where the function is doubt- 

 ful. For this reason, the title of intercostal is much preferable to that 

 of nerve of organic life, and trisplanchnic better than sympathetic an 



