3G8 Miscellaneous Intelligence, 



even by small sparks taken on or near the part : on the contrary, 

 sparks taken into the extremity or knuckles of the fingers, pro- 

 duced good results ; a few scintillations, even, dissipated almost 

 entirely the sensation of heat, and restored the use of the arm. 

 Once, indeed, a slight shock from a Leyden jar brought the hand 

 and fingers into such a state, that being curved, they could not 

 be opened ; but slight scintillations in a few minutes restored it. 

 No permanent good was, however, at any time afforded by the 

 electrical machine, the arm constantly becoming affected by any 

 similar state of the atmosphere. Whether the effect will con- 

 tinue during another thunder season, is anxiously looked for by 

 M. Fusinieri. — Giornalc di Fisica, vii. 284. 



9. Singular imperfection in Vision. — A man about thirty years of 

 age, of a robust constitution, in perfect health, suffering no incon- 

 venience in the head or organ of vision, having good vision, eyes 

 well formed, and in nothing apparently different from what they 

 ought to be, has not the power of distinguishing colours. From 

 the time that he first began to reflect on the appearance of things 

 about him, he perceived that bodies made various impressions on 

 his eyes, according to their colour ; nevertheless he did not ex- 

 perience that sensation by which colours are estimated and dis- 

 tinguished with precision, and in this respect could not distinguish 

 accurately the bodies to which they belonged. The various co- 

 lours appear to him more like gradations in the illumination of 

 the objects around him, than like tints dependent upon diverse 

 refrangibility. This defect has not undergone any change by his 

 advance in age. Amongst the various colours, pale yellow, scarlet, 

 and blue, are perhaps those upon which his judgment is most 

 certain ; but green, faint red, strong yellow, and brown, cause 

 the greatest confusion. The same colour seen alone, but at dif- 

 ferent times, always produces the same sensation ; in this he 

 never errs ; but when it is presented to him with other colours, he 

 is at fault. — Giornale di Fisica, vii. 470. 



10. Insensibility of the Retina, — M. Majendie has stated to the 

 Academy of Sciences, that he has ascertained the insensibility of 

 the retina, in the eye of a woman suffering from cataract. The 

 contact of an instrument with that organ produced no appreciable 

 sensation ; the person recovered sight immediately after the 

 operation. — Ann, de Chim. xxviii. 1 83. 



11. Preservation of Anatomical Preparations. — Dr. Godman 

 objects to Uie substances usually recommended for the preserva- 

 tion of anatomical preparations, such as saltpetre, common salt, 

 corrosive sublimate, and pyroligneous acid, in consequence of their 

 action upon the edges of the knives, the two best as preservers of 



