

TASTE. 



8G1 



undergo a kind of erection when sapid sub- sation ; and if this application be restricted 



stances are brought into contact with them, to one particular spot, we are able to reco"- 



This inference is in complete harmony with nise its place more or less distinctly. In tins 



the relative acuteness of the senses of taste respect, then, the gustative impression resem- 



and touch, in the portions of the surface on bles the tactile ; for whilst we cannot, by our 



which the one or the other class of papillae own consciousness, distinguish the parts of 



is most abundant ; thus the sides and back the retina or of the auditory apparatus on 



part of the tongue are unquestionably the which visual or auditory impressions are 



parts where the gustative sensibility is the made, we can make this distinction in remrd 



greatest, and it is there that the fungiform, to the surface which is supplied by & the 



circumvallate, and simple papillae are most nerves of general sense. This determination 



thickly set; whilst the apex and central part is most precise when the impression is made 



of the dorsum, over which the tactile sensi- on the parts of the tongue of which the gus- 



bility is predominant, is that on which we tative sensibility is most acute ; namely, the 



meet with the largest number of filiform apex, sides, and posterior part of the dorsum; 



papillae. Whether there be any difference being probably aided, however, near the tip 



among the simple isolated papillae, and among by the acuteness of its tactile sensibility. The 



those which are aggregated into the com- impressibility of the middle portion of the 



posite bodies that are termed fungiform and dorsum is greatly inferior ; but still when 



circumvallate, we are scarcely in a con- the gustative sensation has been excited 



dition even to form a guess, until it shall there, it is referred to the spot on which the 



have been determined whether the gustative sapid substance was laid. The contact of 



and tactile nerve-fibres are identical or diverse sapid substances much more readily excites a 



in their endowments. If the former, it will gustative sensation, when it is made to press 



be reasonable to suppose that every papilla upon the papillae, or to move over them. 



" rough which a gustative impression can be Thus there are some substances whose taste 



e in virtue of the penetration of sapid is not perceived when they are simply applied 



atter into its tissue, may also be subservient to the central part of the dorsum of the 



to the reception of tactile impressions from tongue, but of whose presence we are at once 



mechanical stimulation. On the other hand, rendered cognizant by pressing the tongue 



if it should be proved that the gustative sense against the roof of the mouth. The full 



depends on a special set of fibres, we should flavour of a sapid substance, again, is more 



still have to inquire whether the same papilla readily perceived when it is rubbed on any 



may not contain fibres of both classes, so as to part of the tongue, than when it is simply 



minister to both functions ; or whether some brought in contact with it or pressed against 



of the papillae are purely gustative, whilst it. Even when liquids are taken into the 



ue i 



S3 



mat! 



others are purely tactile 



mouth, their taste is most completely discri- 



At present there is no adequate reason to minated by causing them to move over the 

 suppose that there is any essential difference gustative surface: thus the "wine-taster" 

 of function among the papillae covered with a takes a small quantity of the liquor into his 

 soft thin epithelium, whether these be solitary mouth, carries it rapidly over every part of 

 or aggregate. An attempt was made by its lining membrane, and then ejects it. It is 

 Horn * to establish some such diversity ; but not improbable that this exaltation "of the 

 the results of his experiments would rather usual effects is simply due to mechanica 

 lead to the supposition that there is a dif- causes ; the sapid particles being brought by 

 ference in the gustative sensations excited by the pressure or movement into more rapid 

 the same substance, according as it is applied and complete operation on the nerve-fibres, 

 to different regions of the tongue, than to than they would be if simply placed in con- 

 different papillae. Thus he found that more tact with the papillae. 



than three-fourths of the substances which he As in the case of the other senses, so do 



applied to the circumvallate papillae excited we find with regard to that of taste that 



a bitter taste, or one in which a bitter was continual attention to its indications greatly 



associated with some other flavour, especi- increases its acuteness. Thus the " tasters " 



ally an alkaline or saline ; whilst the majority of wine, tea, &c., acquire a power of discrimi- 



of the substances applied to the filiform nation which is truly wonderful to those who 



papillae tasted acid, or acid with a mixture of have not exercised themselves in the same 



bitter and sweet. But since, as we have manner. Thus we have been informed that 



seen, mere mechanical stimulation produces the " taster " to one of the extensive cellars 



different gustative sensations according to the of sherry wines at Cadiz or Seville has not 



part of the tongue to which it is applied, it is the least difficulty in distinguishing the butt 



probable that the difference in Horn's results from which a given sample 3 may have been 



is not to be set down to the account of the drawn, although the number of different va- 



papilla?, but rather to that of the nerves by rieties of the same kind of wine under his 



which they are respectively supplied. keeping may not be less than five hundred. 



Exercise of the Sense. The simple appli- So we are informed by Dr. Kitchener that 



cation of a sapid substance to the gustative many London epicures are capable of saying 



surface is usually sufficient to excite the sen- in what precise reach of the Thames the 



* Ueber den Geschmacksinn des Menschen. Hei- ^ mo . n on tne ta ^J e nas been caught; and the 



lberg, 1825. 



Parisian gourmet is said to be able to distin- 



