

. 2. 1. 12, OF ASSOCIATION. 407 



live association, but not by sensitive association. The event was, 

 that as soon as the gums became sore with a slight ptyalism, the 

 pains about the head and vertigo gradually diminished, and, dur- 

 ing the soreness of his gums, entirely ceased; but I believe re- 

 curred afterwards, though in less degree, 



The idea of inflaming the membranes of the teeth to produce 

 increased sensation in them, and thus to prevent their irritative 

 connexion with those of the cranium, was taken from the treat- 

 ment of trismus, or locked jaw, by endeavouring to inflame the 

 injured tendon; which is said to prevent or remove the spasm of 

 the muscles of the jaw. See Class III. 1.1. 13. and 15. 



M. M. Emetics. Blisters. Issues about the head. Extrac- 

 tion of decayed teeth. Slight salivation. Sorbcntia. Incitantia. 

 Galvanism. 



A lady was suddenly seized with violent vertigo, so as to pre- 

 vent her walking safely across the room; this was attended with 

 considerable diminution of sight; and after various evacuations 

 and other medicines had been tried without cure, Mr. Volta's gal- 

 vanic pillar was used, consisting of about thirty plates of silver, 

 the diameter of about one inch and a half, and as many zinc 

 plates, with interposed circles of cloth moistened with brine. 

 A wire connected with each end of this pillar was approached 

 repeatedly to her temples, which were previously moistened with 

 brine, and 100 galvanic shocks were daily passed through the 

 optic nerves, which soon appeared to be of great advantage, and 

 she soon recovered, both from the vertigo and dimness of sight. 



12. Vertigo ebriosa. Vertigo from intoxication is owing to the 

 association of the irritative ideas of vision with the irritative mo- 

 tions of the stomach. Whence when these latter become much 

 increased by the immoderate stimulus of wine, the irritative mo- 

 tions of the retina are produced with less energy by reverse sym- 

 pathy, and become at the same time succeeded by sensation in 

 consequence of their decreased action. See Sect. XXI. 3. and 

 XXXV. 1. 2. So conversely when the irritative motions of vision 

 are increased by turning round, or by our unaccustomed agitation 

 at sea, those of the stomach become inverted by reverse sympathy, 

 and are attended in consequence with disagreeable sensation. 

 Which decreased action of the stomach is in consequence of the 

 increased expenditure of the sensorial power on the irritative 

 ideas of vision, as explained in Vertigo rotatoria. 



Whence, though a certain quantity of vinous spirit stimulates 

 the whole system into increased action, and perhaps even in- 

 creases the secretion of sensorial power in the brain; yet as soon. 

 as any degree of vertigo is produced, it is a proof, that by the too 



