84 TEN YEARS OF GAME-KEEPING 
partridges more easily than when ‘cold’ (as keepers 
call eggs in which incubation has not started), 
because, when a sitting bird leaves her nest, she 
does not cover up her eggs. These, having 
become smoothed and polished from being sat 
upon, the more easily catch the glint of the sun, 
and therefore the eye of rooks. It seems curious at 
first sight that partridges should cover up their cold 
eggs, but leave fully exposed those which are being 
incubated. The reason, I think, must be that the 
birds’ instinct has been so ordered by Nature to carry 
out her rule—that ‘setty’ eggs must be allowed to 
cool and to absorb oxygen, for the strengthening 
and successful hatching of the embryos. 
One may distinguish between the egg-stealing 
work of a solitary rook and that of a company of the 
rascals. A solitary rook does not hurry, and will 
carry an egg to some open spot with the idea 
(presumably) of enjoying it in safety, and does not 
take all the eggs in a nest, unless they are very 
few, on one occasion. But when a nest is dis- 
covered by a band of the robbers, very short work 
is made of it, and the keeper is likely to find left 
only a few pieces of shell near the ransacked nest. 
Anyone who has watched a whole tribe of rooks 
mobbing a sitting partridge cannot fail to sympathize 
with her, whether in sympathy with partridge- 
shooting or not. For cowardly persistency the 
sight were hard to match. One rook catches sight 
