NORTHERN RAVEN, 123 
dropping them on rocks, for the purpose of breaking them 
to obtain their contents, otherwise beyond his reach, — facts 
observed by men of credit, and recorded as an instinct of the 
Raven by Pennant and Latham. It is, however, seldom that 
these birds, any more than the rapacious kinds, feel an inclina- 
tion for drinking, as their thirst is usually quenched by the 
blood and juices of their prey. The Ravens are also more 
social than the birds of prey, — which arises from the promis- 
cuous nature and consequent abundance of their food, which 
allows a greater number to subsist together in the same place, 
without being urged to the stern necessity of solitude or fam- 
ine, — a condition to which the true rapacious birds are always 
driven. The habits of these birds are much more generally 
harmless than is usually imagined ; they are useful to the farmer 
in the destruction they make of moles and mice, and are often 
very well contented with insects and earth-worms. 
Though spread over the whole world, they are rarely ever 
birds of passage, enduring the winters even of the Arctic circle, 
or the warmth of Mexico, St. Domingo, and Madagascar. 
They are particularly attached to the rocky eyries where they 
have been bred and paired. Throughout the year they are 
observed together in nearly equal numbers, and they never 
entirely abandon this adopted home. If they descend into 
the plain, it is to collect subsistence ; but they resort to the 
low grounds more in winter than summer, as they avoid the 
heat and dislike to wander from their cool retreats. They never 
roost in the woods, like Crows, and have sufficient sagacity to 
choose in their rocky retreats a situation defended from the 
winds of the north, — commonly under the natural vault formed 
by an extending ledge or cavity of the rock. Here they retire 
during the night in companies of 15 to 20. They perch upon 
the bushes which grow straggling in the clefts of the rocks; 
but they form their nests in the rocky crevices, or in the 
holes of the mouldering walls, at the summits of ruined towers ; 
and sometimes upon the high branches of large and solitary 
trees. After they have paired, their fidelity appears to continue 
through life. The male expresses his attachment by a particu- 
