LOCALITY AND NATURE. 171 
track over everything ; if he comes to the wall of a house 
he goes straight up without the smallest hesitation, and 
explores a good height before he comes down again ; if 
he finds a loaf of bread in the cellar he never thinks of 
going round it, but travels in a Roman road up and over. 
So do the armies of ants in warmer climates, and this 
proceeding in an invariable line irrespective of. obstacles 
seems to be peculiar to many creatures, and is the reason 
why such ‘ plagues’ were and are so dreaded. Nothing’ 
could divert the straight march of the locusts ; nothing 
could divert the course of the millions of butterflies that 
sometimes cross the Channel and arrive here from the 
Continent. 
The tenacity of insects in anything they have once 
begun is shown in many ways; you cannot drive away 
a fly or a gnat, and if a colony of ants take up their 
home in the garden they will hardly move till all are 
destroyed. Aristotle mentions the diseases of swine, so 
it will not be amiss to record that in the country swine 
are supposed to suffer from water-brash, and to relieve 
themselves by eating dry earth, for which purpose those 
that run loose are continually tearing up the ground. 
Human beings so affected show a similar tendency for 
dry food, as oatmeal. Sometimes the liver of calves and 
bullocks is small and: dry, of very little use for food ; 
this is found to be due to the neglect of providing them 
with dry standing-ground when fattening. To ensure 
their fattening properly they should stand on dry and 
high ground, and they should be plentifully supplied 
with dry litter. This fact may be of value to some 
suffering person ; it points to the necessity of dry warm 
feet, dry subsoil, and drainage if the liver is to be in 
good order. Popular suspicion, if not science, attaches 
many other diseases besidcs those that actually consume 
