472 THE POPULAR SCIENCE MONTHLY. 



its gustatory properties. In civilized life, we find everything ready 

 labeled and assorted for us ; vs^e comparatively seldom require to roll 

 the contents of a suspicious bottle (in very small quantities) doubtfully 

 upon the tongue in order to discover whether it is pale sherry or Chili 

 vinegar, Dublin stout or mushroom ketchup. But in the savage state, 

 from which, geologically and biologically speaking, we have only just 

 emerged, bottles and labels do not exist. Primitive man, therefore, in 

 his sweet simplicity, has only two modes open before him for deciding 

 whether the things he finds are or are not strictly edible. The first 

 thing he does is to sniff at them, and smell being, as Mr. Herbert Spen- 

 cer has well put it, an anticipatory taste, generally gives him some 

 idea of what the thing is likely to prove. The second thing he does is 

 to pop it into his mouth, and proceed practically to examine its further 

 characteristics. 



Strictly speaking, with the tip of the tongue one can't really taste 

 at all. If you put a small drop of honey or of oil of bitter-almonds on 

 that part of the mouth, you will find (no doubt to your great surprise) 

 that it produces no effect of any sort ; you only taste it when it begins 

 slowly to diffuse itself, and reaches the true tasting region in the mid- 

 dle distance. But, if you put a little cayenne or mustard on the same 

 part, you will find that it bites you immediately — the experiment 

 should be tried sparingly — while if you put it lower down in the mouth 

 you will swallow it almost without noticing the pungency of the stimu- 

 lant. The reason is, that the tip of the tongue is supplied only with 

 nerves which are really nerves of touch, not nerves of taste proper ; 

 they belong to a totally different main branch, and they go to a differ- 

 ent center in the brain, together with the very similar threads which 

 supply the nerves of smell for mustard and pepper. That is why the 

 smell and taste of these pungent substances are so much alike, as every- 

 body must have noticed ; a good sniff at a mustard-pot producing 

 almost the same irritating effects as an incautious mouthful. As a 

 rule, we don't accurately distinguish, it is true, between these differ- 

 ent regions of taste in the mouth in ordinary life ; but that is be- 

 cause we usually roll our food about instinctively, without paying 

 much attention to the particular part affected by it. Indeed, when one 

 is trying deliberate experiments in the subject, in order to test the 

 varying sensitiveness of the different parts to different substances, it is 

 necessary to keep the tongue quite dry, in order to isolate the thing you 

 are experimenting with, and prevent its spreading to all parts of the 

 mouth together. In actual practice this result is obtained in a rather 

 ludicrous manner — by blov^^ing upon the tongue, between each experi- 

 ment, with a pair of bellows. To such undignified expedients does the 

 pursuit of science lead the ardent modern psychologist. Those domestic 

 rivals of Dr. Forbes Winslow, the servants, who behold the enthusiastic 

 investigator alternately drying his tongue in this ridiculous fashion, as 

 if he were a blacksmith's fire, and then squeezing out a single drop of 



