THE SENSE OF TASTE. 141 



extremities of the nerves of taste. The proof of this lies in the often-observed 

 fact that, when intensely bitter substances have been swallowed in the shape 

 of pills so well enveloped that they pass over the tongue without exciting the 

 characteristic taste, that taste will nevertheless arise in the mouth after a cer- 

 tain time.' As regards the second sort of after taste, ^yhere its quality differs 

 from that of the primary taste, we are again left in doubt how far it is objective, 

 how far subjective. It is very possible that certain objects of taste suffer, within 

 the raucous tissues, a rapid change or chemical decomposition, and in this al- 

 tered condition affect the nerves of taste in a different manner than at first. 

 But it is also conceivable that the different after-taste results from a spontane- 

 ous reaction of the nerve apparatus ; a supposition, however, which admits 

 neither of proof nor .closer examination. 



In like manner with the impressions of touch and smell, of which we have 

 elsewhere treated, those of taste are regularly and unavoidably associated with 

 ideas which mankind in general are apt erroneously to identify with the im- 

 pressions themselves. On this head, our previous discussions authorize us to be 

 brief. With the impressions of taste is immediately connected the idea of an 

 external object, as cause of the sensation, and with so little consciousness of the 

 distinction between the sensation and the idea that we believe ourselves to be 

 directly tastin;^- the object as such, and impute to it the qualities of the* sensa- 

 tion as a property. Thus every one speaks of sweet and sour substances as if 

 the sweetness' or sourness were a property of the .substance itself, just as we 

 speak of red and blue objects in the meaning that the color is a property of the 

 object. Most probably we arrive at the idea of an external object as cause of 

 the sensation of taste not through this sensation itself, but through the accom- 

 panying impressions of touch, which simultaneously enable us to form the idea 

 of the 2>la(^<i at which the gustatory impression takes effect. With sensations of 

 taste are also connected ideas of pleasantness, unpleasantness, nauseousness, &c., 

 which are in like manner erroneously confounded with the sensations. An im- 

 pression on the organs of sense cannot in itself be pleasant or unpleasant. 

 Further, it is often not the immediate gustatory impression which calls up the 

 idea, for this idea may take its shape from mental associations previously estab- 

 lished, or in part from simultaneous sensations of taste or smell. 



The above is all that we have felt authorized by the present state of our 

 knowledge respecting the physiology of the sense of taste to impart to the reader 

 as worthy of his confidence. We might here desist, but it is, perhaps, proper 

 to offer a few remarks in regard to the practical uses to which the sense of taste 

 is adapted, even if the first considerations which present themselves, as was the 

 case when we formerly treated of the sense of smell, may seem calculated to dis- 

 parage its value as an endowment of the human or animal economy. In this 

 point of view, it is a matter of indifference whether we ask, of what advantage 

 is the sense of taste 1 or what was the design in endowing the organism with that 

 sense ? The answer to both forms of inquiry rests essentially on the same prin- 

 ciples. It is customary to regard the sense in question as a sentinel, so to speak, 

 of the digestion, stationed at the portal of the alimentary passages, to challeuge 

 the various articles which present themselves for admission, and to enable us to 

 discriminate the hurtful from the wholesome. Nor is this view incorrect, only it 

 is necessary, first, to assign the limits vithin which this sentinel may be trusted ; 

 and, secondly, to inquire how far its function is an independent one. It would 

 certainly be disastrous for nutrition and health if we committed ourselves blindly 

 to such a monitor as this ; death from inanition or poison must lie everywhere in 

 wait for us, if we resigned ourselves without reserve to its indications. The 

 sense of taste is itself indeed no sentinel ; the quality of a sensation of taste can, 

 of itself, in nowise disclose to us whether a substance is wholesome or unwhole- 

 some, seeing that there are many tasteless substances which are the former, and 

 not a few of the latter which are well flavored. The sense of taste is in this 



