40 
POPULAR SCIENCE REVIEW. 
mistaken in his observations, and if open-topped nests have 
been unknown in the regions of his observation, it is strange 
that they should be found elsewhere. The inference seems to 
be that variations from a normal pattern may be local ; and 
perhaps a careful comparison of the building proceedings of 
the martins in different counties might throw light upon their 
ways, and lead to a higher view of their intelligence. 
I may be fortunate in having my house frequented by a more 
experimental race of martins than are common, and there may 
be an advanced thinker among them, analogous to the reformers 
who sometimes spring up amongst stagnant tribes of men. I 
cannot, however, venture to flatter myself that this is the true 
explanation until I hear the result of careful inquiries in other 
quarters. All I can say is, that the martins’ nests round my 
roofs exhibit nearly as much variety in form as the houses of 
the human folks in the village below, and a reason can usually 
be seen for the variations they display. Open-topped nests 
have been found in the most sheltered places. When the birds’ 
abodes have been built in couples, like the semi-detached villas 
in the outskirts of towns, the entrances have been arranged so 
as not to come too close together. The distances are sufficient 
to render collisions of out-going and in-going birds improbable, 
and I notice other adaptations of means to ends. 
In summer the martin families seem scarcely to sleep at all. 
At midnight and -at early morn the young ones twitter. Late 
in the evening the parents keep up their elegant flight, and 
they are at it again as twilight passes into dawn. 
