406 HALLUCINATIONS OCCASIONED BY DRUGS. 



Co-existence most commonly the case, the derangement which gives origin 

 of retinal in- t these appearances is not limited to the retina, but, arising 



sanity and cer- , . 



ebrai sight. in some constitutional affection, involves more or less com- 

 pletely the entire nervous apparatus of the eye, retinal insanity and cerebral 

 vision occur together. In those cases which have been investigated in 

 a philosophical manner by the patients themselves, this complication is 

 often distinctly recognized. Thus Nicolai, the Prussian bookseller, who 

 published in the Memoirs of the Royal Academy of Berlin an interesting 

 account of his own sufferings, states that, of the apparitions of men and 

 women with which he was troubled, there were some which disappeared 

 on shutting the eyes, but some did not. In such a case there can be no 

 doubt that the disease affected the corpora quadrigemina and the optic 

 thalami as well as the retina. 



This condition, in which the receiving centres and registering ganglia 

 at the base of the brain are engaged, is the one which yields the most 

 striking instances of hallucinations in which apparitions and visions co- 

 Brought on ar- exist. It can, like the less complicated forms, be brought 

 tificiaiiy by ai- artificially, as in the delirium tremens which follows a 



conol, opium, > 7 



&c. cessation from the customary use of alcohol, or in the exalt- 



ation by the purposed administration of opium or other drugs. In this, 

 as in those forms, it is the localization of the phantom among the bodies 

 and things around us that begins to give power to the illusion. The 

 form of a cloud no bigger than the hand is perhaps first seen floating 

 over the carpet, but this, as the eye follows it, takes on a sharp contour 

 and definite shape, and the sufferer sees with dismay a moping raven on 

 some of the more distant articles of furniture. Or, out of an indistinct 

 cloud, faces, sometimes of surprising loveliness, emerge, one face succeed- 

 ing as another dies away. The mind, ever ready to practice imposture 

 upon itself, will at last accompany the illusion with grotesque or even 

 dreadful inventions. A sarcophagus, painted after the manner of the 

 Egyptians, distresses the visionary with the rolling of its eyes. Martin 

 Luther thus more than once saw the devil under the well-known form 

 popularly assigned to him in the Middle Ages. 



As the nervous centres have been more profoundly involved, these 

 Visions of false v i s i ons Become more impressive. Instead of a solitary 

 or exaggerated phantom intruding itself among recognized realities, as the 

 shade of a deceased friend qpens the door and noiselessly 

 steps in, the complicated scenes of a true drama are displayed. The 

 brain becomes, as it were, a theatre. According as the travel or the 

 reading of the sick man may have been, the illusion takes a style : black 

 vistas of Oriental architecture, that stretch away into infinite night; tem- 

 ples, and fanes, and the battlemented walls of cities ; colossal Pharaohs, 

 sitting in everlasting silence, with their hands upon their knees. " ] 



