250 Observations and Experiments on the Sense of Taste. 



tween the two metals, is not a taste, only a sort of feel. 

 When I tried it with a silver spoon, (which I presume is 

 purer silver than a crown piece) and zinc, a strong and nasty 

 taste took place immediately on removing the metals, and 

 leaving the tongue at liberty to touch the palate. But then 

 there was a smell too, exactly like the taste ; it was on the 

 spoon, not on the zinc, I think. It was also like the smell of 

 a spoon with which an egg has been eaten, and the spoon was 

 tarnished as it is by that ; whether owing to albumen in the 

 saliva, or in the nerve, I do not know. This is so full a proof 

 of my supposition, that I need not, but for curiosity, go fur- 

 ther. 



When I try it with a crown piece and zinc, the tingling in 

 the tongue greatly abates, on removing the metals, and no 

 taste, that I can perceive on smacking, succeeds. 



What is called, a brassy taste, which is referred, I believe, to 

 this same galvanic principle, is certainly connected with a strong 

 smell. Brass, and even copper alone, at least copper money, we 

 know has, when rubbed, a good deal of smell. I still, there- 

 fore, see no reason to doubt the truth of my opinion, that, 

 when we have any thing in the mouth, every perception of it 

 which we should ordinarily call tasting, and not feeling, is, in 

 fact, a smell perceived in the nose only, and conveyed thither 

 by the air when passing through the internal aperture. 



In the case where the taste is perceived as soon as the breath 

 turns to go out, I considered that what is breathed out had 

 been in those experiments before breathed in, from or through 

 the mouth ; so that the air, which went out through the nose, 

 had come, originally at least, from the forepart of the mouth, 

 if it did not do so immediately. And, if it were not for this 

 consideration, the fact would appear not to be agreeable to 

 the theory which I am maintaining; since merely breath- 

 ing out air through the mouth, or even through the nose, 

 does not, in one operation, carry air from the fore-part of the 

 mouth through the nose; and, therefore, if the substance 

 tasted is, as I supposed it generally to be while it is chew- 

 ing and moved about by the tongue, I say, if it is in that 

 part of the mouth which is forwarder than the passage up 

 into the nose, it would not, but for the consideration just 



