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SCIENCE 



[N. S. Vol. XL. No. 1040 



6. Tie vagus, therefore, acts both as whip and 

 bridle, spur and snaffle to the heart. The intrinsic 

 ganglia being only bridges for the transmission of 

 impulse, the true function of the vagus, in Gas- 

 kell's view, is not inhibitory but quiescent, acting 

 upon the heart muscle itself. Gaskell revives 

 Borelli's hypothesis* that the effect is chemical. 

 The vagus is defined as the anabolic nerve of the 

 heart. Inhibition is auabolism.s The vagus is a 

 trophic nerve, both for muscle and ganglia. 



7. Galvanometer observations showed that stim- 

 ulation of the accelerator and inhibitor fibers pro- 

 duced opposite electrical effects which were inde- 

 pendent of contraction, since they could be ob- 

 served in a quiescent heart. These electromotive 

 effects were first mapped and measured by A. D. 

 Waller in 1889. Einthoven 's string galvanometer 

 made it possible for the physician to obtain ' ' elec- 

 trocardiograms " or telegrams from the heart, giv- 

 ing its electromotive condition, a field of investiga- 

 tion which Gaskell was the first to enter. 



8. Gaskell regards certain discrepancies in the 

 findings of experimentation upon the heart as due 

 to chemical and nutritive changes in different 

 hearts at different times of the year. 



These results, the most important work on 

 the heart since Ludwig, are embodied partly 

 in Gaskell's Croonian Lecture of 1881, and, in 

 more mature and complete form, in his splen- 

 did monograph in Schaefer's " Physiology " 

 (1898). His comparative researches on the 

 innervation of difPerent animals lead him to 

 his next great work, the mapping out and 

 interpretation of the nerve supply of the en- 

 tire vascular and visceral systems, culmina- 

 ting in his exhaustive memoir of 1886." In 

 this, it was shown, by microscopical observa- 



* Borelli believed that a contracting muscle 

 actually increases in bulk through a fermentation 

 started in its substance from a hypothetic " sue- 

 cms" discharged from the nerve. 



5 This view is opposed by Langley, and it does 

 not harmonize with the experiments on isolated 

 hearts in Ringer's solution by Howell and others. 

 The limiting semi-permeable envelope of a living 

 cell, organ or body is usually regarded as the 

 agent of anabolism, preventing the undue dissi- 

 pation of energy. 



6 " On the Structure, Distribution and Function 

 of the Nerves which Innervate the Visceral and 

 Vascular Systems," Jour. Fhysiol., Lond., 1886, 

 VII., 1-80. 



tion, that the supply of nerves from the spinal 

 cord to the chain of sympathetic ganglia 

 originates mainly from the thoracic and upper 

 lumbar regions, in which white rami, made 

 up of meduUated nerves, form the connection. 

 Although it is now known that the cerebro- 

 spinal system alone governs reflex actions, it 

 was formerly supposed that the sympathetic 

 system was also concerned in the change of 

 afferent impulses to efferent. The mapping 

 out of the sympathetic nerves in their distri- 

 bution from the spinal roots between the sec- 

 ond thoracic and second lumbar vertebrse and 

 the inclusion of the nerves proceeding from 

 the cranial and sacral nerve roots, as a part of 

 a greater system, distributed to the viscera, 

 blood vessels, ductless glands and all organs 

 or regions supplied by smooth (involuntary) 

 muscle, was the special work done by Gas- 

 kell. This system was defined and interpreted 

 by Langley as the " autonomic " system, the 

 function of the sympathetic and cranio-sacral 

 autonomics being the redistribution of im- 

 pulses along all efferent paths which do not 

 terminate in voluntary muscle, these paths 

 proceeding from a neuron in the spinal cord 

 to an external sympathetic ganglion or syn- 

 apse, from whence the post-ganglionic fibers 

 pass to the glands or muscles. The study of 

 these paths began with Gaskell's investiga- 

 tions on the accelerator nerves of the heart. 

 Langley's nicotine method proved the means 

 of isolating individual synapses, as the drug 

 acts selectively on the autonomic ganglia and 

 not on the cerebro-spinal. In internal medi- 

 cine, the connection of the autonomic systems 

 with the ductless glands forms part of the in- 

 teresting theory of the correlation of the in- 

 ternal secretions advanced by the Viennese 

 clinicians, Eppinger, Falta and Eiidinger. 



The remaining years of Gaskell's life were 

 taken up with his theory, formulated in 1889, 

 that the central canal of the nervous system 

 was originally the lumen of a primitive gut, 

 which is elucidated at length in his book on 

 "The Origin of Vertebrates" (1908). In 

 1893, in connection with his work on the 

 Hyderabad Chloroform Commission, Gaskell, 



