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Generally the first sensation experienced is that of want of breath, 

 which is followed by deep and laboured inspirations : this dyspnoea 

 occurs in healthy persons in about a minute or two. While these 

 symptoms are occurring, we observe a considerable disturbance of the 

 heart's action. At first there is increase in the number of its pulsa- 

 tions, with decreased power, as may be easily ascertained by the pulse. 

 To this supervenes a retardation of the heart's action of about 4 to 5 

 beats a minute of its initial number, at the same time there being 

 decrease of the force of the pulse. These motory affections of the 

 heart are frequently accompanied by slight uneasiness over the pre- 

 cordial region. 



At the next stage the heart's action may become so much en- 

 feebled as to produce syncope. 



The stomach symptoms which are produced by irritation of the 

 vagus are marked by uneasiness over the stomach, in some cases in- 

 creasing so as to cause a sensation of nausea. 



I have not hitherto observed any motor effects on the stomach, but 

 in the intestines borborygmi occur, as after irritation of the vagus 

 on animals. I am unable at present to state whether any glycose 

 urine is produced. 



On the ear corresponding to the side compressed are felt tingling 

 and heat, which often last upwards of half an hour after the removal 

 of pressure. 



In only one instance have I been able to detect any influence on 

 the pupil. It at first became dilated, and subsequently contracted 

 after the pressure was removed. 



All the above symptoms quickly disappear after the removal of the 

 irritating cause, leaving, however, a degree of lassitude, fatigue, and 

 lowness of spirits, which may last for some hours. 



It is easily ascertained that the symptoms above described are not 

 owing to compression of the carotid artery, as they may be produced 

 without obliterating the calibre of the artery ; or, vice versa, the course 

 of the blood may be completely interrupted in the artery without pro- 

 ducing any of the symptoms enumerated. 



On another opportunity I intend to show the applications which 

 this mode of investigating the condition of the vagus presents in a 

 practical point of view, for the diagnosis of various functional de- 

 rangements or diseases of the vagus. 



