LAW OF CORRELATION. 87 



powerful, enabling the animal to take long leaps, while 

 the fore-paws are proportionally small." ] 



In blind persons the sense of touch attains a deli- 

 cacy that is surprising. 



" It is well known that Dr. Saunderson, the cele- 

 brated blind Professor of Mathematics at Cambridge, 

 not only acquired a very accurate knowledge of med- 

 als, but could even distinguish genuine medals from 

 imitations, more certainly than most connoisseurs in 

 full possession of their senses." a 



Cases are on record of blind persons who could not 

 only distinguish colors, but shades of the same color. 

 The muscular sense which is employed by the blind, 

 in connection with touch, in discriminating the form, 

 peculiarities of surface, and size of objects, becomes 

 in these cases remarkably developed. 8 



It is stated that persons affected with color-blind- 

 ness frequently have a defective musical ear. 4 



The sense of smell, in some blind persons, is so ex- 

 ceedingly acute that they are enabled, by it alone, to 

 recognize persons not in immediate contact with them. 



" In the well-known case of James Mitchell, who 

 was deaf, blind, and dumb, from his birth, it was the 

 principal means by which he distinguished persons, 

 and enabled him at once to perceive the entrance of a 

 stranger." 5 



1 " Comparative Physiology," p. 130. 



2 "Cyclopaedia of Anatomy and Physiology," vol. iv., p. 1178. 



3 Ibid., loc. cit. 



4 See Dr. Earle's article in the American Journal of the Medical 

 Sciences, vol. xxxv., p. 347 ; and article " Vision," " Cyclopaedia of Anat- 

 omy and Physiology," vol. iv., p. 1453. 



6 " Cyclopaedia of Anatomy and Physiology," vol. iv., p. 702. 



