Every animal

is supplied with moisture, and, if the animal be deprived of the same by natural causes or artificial means, death ensues: further, every animal has another part in which the moisture is contained. These parts are blood and vein, and in other animals
there is something to correspond; but in these latter the parts are imperfect, being merely fibre and serum or lymph. Touch has its seat in a part uniform and homogeneous, as in the flesh or something of the kind, and generally, with animals supplied
with blood, in the parts charged with blood.