THE APPARENT CRUELTY OF NATURE. 261 
feathered race the sense of touch—upon the existence of which, 
in a somewhat highly developed degree, of course, the posst- 
bility of experiencing pain absolutely depends—is not highly 
developed. The conditions of the entire structure practically 
forbid that it should be so. The body is entirely enveloped 
in a dense coating of feathers ; clearly tactile nerves beneath 
this would be useless. The limbs are clothed either with 
plumes or with horny scales ; and the same result necessarily 
follows. The mouth, again,—usually a highly sensitive 
region—is enclosed in a hard and callous beak, which only 
in such birds as the duck and the apteryx appears to possess 
anything approaching to delicacy of touch; while even the 
tongue is encased in a horny sheath, necessarily rendering 
the sense of taste rudimentary in the extreme. Such being 
the case, it would seem scarcely possible that birds can ever 
be conscious of a keen sense of pain, although it would be 
rash indeed to assert that the sensation of pain is altogether 
unknown to them. 
Only the mammals remain to be considered ; and there 
can be no reasonable doubt that these, as a class, are 
susceptible to pain, although not a few are as densely clothed 
with scales, spines, or fur as the birds with feathers. To what 
extent this susceptibility may extend, however, is another and 
a wider question. 
2. This, of course, brings us to the second branch of our 
subject ; the question, namely, of the degree of pain experi- 
enced by those animals in which sensitive nerves can be 
proved to exist. In other words, are we justified, when an 
animal exhibits unmistakable signs of suffering, in ascribing 
to that suffering a character and degree similar to that which 
we ourselves should experience under the like circum- 
stances ? 
But how, we may ask at the very outset of our enquiry, 
are we to obtain a definite standard for the comparison ? for 
the pain consequent upon an injury to one man is often far 
more intense and prostrating than the pain consequent upon 
a precisely similar injury to another. We all know how 
differently a simple surgical operation—such as the extraction 
of a tooth—affects different individuals. One endures tor- 
tures, both in anticipation and in reality ; another scarcely 
suffers at all. 
A very curious case of this character was related to me by 
my brother, who isa schoolmaster, and who was himself a 
_ witness of the operation in question. 
