INTRODUCTION. 
XV 
nests, adapting them as though reason had been their guide. 
The most remarkable on record is that of the Rooks, which for 
ten successive years, built their nest upon the vane at the top of 
the Newcastle Exchange, revolving with every change of wind. 
The House Sparrow, the nest of which, when built in trees, is 
large and carefully arched over, dispenses with the labour of 
constructing its own roof, when it places it under the eaves of 
our dwellings. 
In coming to the conclusion of this, the Third Edition of our 
British birds’ eggs, it is natural to revert to the time—some 
twenty-five years ago—when the earliest pages of the Oology 
first saw the light, and to note with pleasure the great progress 
which has been made during that period towards a knowledge 
of the subject. The book (“ the Oology”) was itself as migra¬ 
tory as the birds, the eggs of which are depicted in its pages; 
many of the plates were drawn at night after a long day of rail¬ 
way surveying in the fields, and the letter-press was printed 
wherever the author happened to be stationed at the time. 
There were few collectors to aid him in those days; and it is 
with a grateful feeling he remembers now the helping hand 
which was then held out to him by his friend, Mr. Yarrell. 
Many eggs, which are now to be had in profusion, were then 
scarcely known; and a large number, which in my most hopeful 
hours I never expected to see, have been figured in the succeed¬ 
ing editions of the work. So little was known as to our British 
birds’ eggs at the commencement of the “ Oology,” that its 
plates were published unarranged, so as to receive new materials 
during its progress, and it was with feelings of delight which 
leave a bright memory behind them, that the kindness and libe¬ 
rality of correspondents, such as Mr. Spurgeon and Mr. Dash- 
wood, enabled me to add one beautiful thing after another to 
the list, until the extended researches of Mr. Salmon, in Ork¬ 
ney ; Mr. Atkinson and Mr. Procter, in Iceland; my own bird- 
