i88 5 .] 
The Inter-Relations of the Senses. 
285 
VII. THE INTER-RELATIONS OF THE SENSES. 
we consider that the senses of man and of the ver- 
(jy tebrate animals generally * are merely modifications of 
the common reaction to impressions from without we 
may sometimes wonder that they are as isolated as we 
adtuahy find them. It might be expedted that any stimulus 
anectmg one of the sense-organs would frequently have an 
influence upon some other also, each organ duly recording 
the impression made in its own language. We might even expedt 
tnat in ceitain cases one sense-organ would vicariously per- 
foim the duties of another. Fadts pointing in this diredtion, 
nowever, are rare, obscure, and not always well authenti- 
cated. We hear, indeed, of mesmeric subjedts receiving 
light impressions, and even being able to distinguish objects 
b) means of the skin of the forehead, the tips of the finders, 
or of the nose, &c. But such phenomena, even if established’ 
are of doubtful interpretation. 
The relations between the senses of smell and taste are 
much moie intimate than those between that of touch and 
any of the other four. It is even questioned whether either 
scent 01 taste can exist in anything more than a rudimentary 
foim independently of the other. We know a lady who, as 
far as we can rightly interpret her very untechnical language, 
smells, or at least recognises, odours more with the root of 
the tongue and the palate than with the nose. She is very 
susceptible to all manner of scents, pleasant or offensive, 
and is always the first of her family to raise the alarm if 
there has been a slight escape of gas, if a candle has been 
blown out, if the chimney smokes, or if the cook is indulging 
in the preparation of acroleine. But to use her own expres- 
sion, she “ breathes ” rather than smells the odour. Here, 
then, we have at least an approximation to vicarious adtion, 
the posterior end of the tongue doing duty for the nose. 
A curious fadt is that the two allied senses in question, 
specially related as they are to that impulse which in its 
twin forms is the cause of nearly the sum total of animal 
adtivity, sometimes give each other the lie. Thus the nose 
tells us that the durrian fruit is loathsome and repugnant as 
* Our knowledge of the senses of the invertebrate animals is very rudimentary. 
We know not even their number, much less to what extent they have been 
differentiated from each other. 
