126 SENSES. 



tively rigid. This extension of the papillae is not conjectural , 

 it is founded on anatomical observation, and, in some cases, 

 may be seen and felt by persons of acute and discerning sen- 

 sations. When a man in the dark inclines to examine any 

 substance, in order to discover its figure, or other qualities, 

 he perceives a kind of rigidity at the tips of his fingers. If 

 the fingers are kept long in this state, the rigidity of the 

 nervous papillae will give him a kind of pain or anxiety, which 

 it is impossible to describe. The cause of this pain is an 

 over-distention of the papillae If a small insect creeps on a 

 man's hand, when the papillae are flaccid, its movements are 

 not perceived; but, if he happens to direct his eye to the 

 animal, he immediately extends his papillae, and feels distinctly 

 all its motions. If a body be present, which, in the common 

 state of the nerves, has scarcely any sensible order, by ex- 

 tending the papillae of the nostrils, an agreeable, disagreeable, 

 or indifferent smell will be perceived. When two persons 

 are whispering, and we wish to know what is said, we stretch 

 the papillae, and other organs of hearing, which are exceed- 

 ingly complex. If a sound is too low for making an im- 

 pression on the papillae in their natural state of relaxation, 

 we are apt to overstretch the organ, which produces a pain- 

 ful or irksome feeling. When we examine a mite, or any 

 very minute object by the naked eye, a pain is propagated 

 over every part of that organ. Several causes may concur in 

 producing this pain, such as the dilating of the pupil, and the 

 adjusting the crystalline lens ; but the chief cause must be 

 ascribed to the preternatural intumescence and extension of 

 the papillae of the retina, the substance of which is a mere 

 congeries of nervous terminations. This circumstance con- 

 firms a former remark, that the immediate organs of sensation 

 are more copiously supplied with nervous papillae than those 

 parts whose uses require not such exquisite sensibility ; for a 

 distinction in this respect is observable even among the sen- 

 sitive organs themselves. They are furnished with nerves 

 exactly proportioned to the subtilty of the objects whose im- 

 pressions they are fitted to receive. The eye possesses by 

 far the greatest number. The particles of light are so minute, 

 that, had not this wise provision been observed in the con- 

 struction of the eye, it could never have been able to distin- 

 guish objects with such accuracy as at present it is capable 

 of performing. When an insipid body, or a body which 

 conveys but a feeble sensation of taste, is applied to the 

 tongue, we are conscious of an effort which that organ makes 



