THE RAT. 135 
enamel and dentine are worn away very much more rapidly than the remainder 
of the teeth, so that the peculiar chisel-edge of the teeth is continually 
preserved. Following—perhaps unconsciously—the structure of these teeth, 
our cutlers have long been accustomed to make their chisels on the same 
principle; a thin plate of steel being strengthened with a thick backing 
of iron. 
The Rodent animals are widely spread over the entire globe, and are very 
numerous, comprising nearly one-third of the mammalia. 
FEw animals are so well known or so thoroughly detested as the common 
Brown Rat, or Norway Rat, as it 15 sometimes erroneously called. 
It is an exceedingly voracious animal, eating all kinds of strange food, and 
not sparing its own species in times of scarcity. Vhe havoc which an army 
of Rats will make among the corn-ricks is almost incredible, while they carry 
on their depredation with so much secrecy that an unpractised eye would 
think the stacks to be sound and unharmel. Fortunately they can easily be 
dislodged from any rick by taking !t down and repiacing it on proper 
“ staddles,” taking great care that no stray weeds or branches aflord a toot- 
hold to these persevering marauders. While the rick is being rebuilt, no 
particular care need be taken to shake the Rats out of the sheaves, for, as 
they are thirsty animals, they will 
be forced to leap from the stack 
in search of water, and then will 
not be able to return. 
Mice can subsist in a stack by 
means of the rain and dew which 
moisten the thatch, and may be 
often seen licking the straws in 
order to quench their thirst. But 
the Rats are less tolerant of thirst, 
and are forced to evacuate their 
premises. When mice and Rats are found inhabiting the same stack, the 
former animals reside in the upper parts, and the Rats in the lower. 
Rats are not without their use, especially in large towns, which but for 
their never-failing appetites would often be in very sad case. Taking for 
example the metropolis itself, we find that the sewers which underlie its whole 
extent are inhabited by vast hordes of Rats, which perform the office of 
scavengers by devouring the mass of vegetable and animal offal which is daily 
cast into those subterranean passages, and which would speedily breed a 
pestilence were it not removed by the ready teeth of the Rats. So that, when 
kept within proper bounds, the Rat is a most useful animal, and will continue 
to be so until the drainage of towns is constructed in a different manner. 
Rats are very cleanly animals, always washing themselves after every meal, 
and displaying the greatest assiduity in making their toilet. They also exhibit 
considerable delicacy of palate wherever they find a sufficiency of provisions, 
although they are in no way nice in their diet when pressed by hunger. If, 
for example, a party of Rats discover an entrance into a butcher’s storehouse, 
they are sure to attack the best parts of the meat, utterly disdaining the neck, 
the shin, or other coarse pieces. 
-There is one peculiarity in the structure of the Rat which is worthy of 
notice. These animals are able not only to ascend a perpendicular tree or 
wall by the aid of their sharp hooked claws, but also to descend head fore- 
most with perfect ease. In order to enable them to perform this feat, their 
hind legs are so made that the feet can be turned outwards, and the claws 
hitched upon any convenient projections. 
However unpromising a subject the Rat may appear, it has often been tamed, 
THE RAT.—(Mus Décumanus.) 
