430 INJURIES OF 



of the median line, near the outside of the anterior pyramid, will 

 cause a rabbit four months old to turn to the right, if made on the 

 right side ; and to the left, if made on the left. 



5. Notwithstanding the decussation of the anterior pyramids, a 

 division of one or both had no sensible effect, except, perhaps, 

 that of retarding motion a little ; the section of the corpora 

 restiformia does not seem to affect general motion ; and a com- 

 plete division of one half of the chorda oblongata neither affects 

 sensibility nor prevents irregular motions, though the power of 

 volition appears lost on the same side. 



The same phenomena occur in disease. Persons labouring 

 under hysteria or chorea sometimes reel violently or spin round. x 

 Persons have been known to feel an impulse to move forwards 

 or backwards, y An infinite variety, however, of extraordinary 

 and regular movements also occur, and frequently vertigo attends 

 them, whatever their variety. Vertigo cannot be their cause, as 

 they are so various in different cases, and they or it frequently 

 exist alone. 



From these experiments I draw no inference. The consider- 

 ations already mentioned prevent me from concluding that the 

 parts which are cut are the sole organs concerned in giving origin 

 to the peculiar motions, that their sole purpose is for such mo- 

 tions, or even that peculiar motions depend originally upon them. 

 We can only say, as in the undoubted and numerous cases of 

 amaurosis following an injury of the supra-orbital or infra- 

 orbital nerve, and as in regard to the peculiar motion said by 



x See Med. Chir. Trans, vol. v. p. 1. sqq., also vol. vii. p. 237. sqq. 



M. Serres mentions a drunken shoemaker who spun round till he died, and 

 in whom the only morbid appearance was disease of a crus cerebelli. (Dr. Ma- 

 gendie's Journ. t. iv. p. 405. sq.) 



y In a man who had an irresistible desire to move forwards, tubercles were found 

 particularly at the anterior part of the hemispheres. ( Dr. Magendie, Journal de 

 PhysioL t. iii.) I have seen several epileptic youths with this propensity. They 

 would walk away to a very considerable distance, without knowing why ; and this 

 repeatedly. A hemiplegic young man would walk upwards of 50 miles from 

 home, and be lost for a considerable time. I frequently see persons with a pro- 

 pensity to precipitate themselves forwards. In some there is desire merely to 

 leave their abode, and they walk to gratify this, or travel by some conveyance. 

 Dr. Laurent exhibited a girl at the Academic Royal de Medecine, who, in irre- 

 gular hysteric attacks, rushed rapidly backwards, (Dr. Magendie, Precis de Phys. 

 p. 409. sq.) 



