HOUSE MARTEN. 143 



nests are washed down every hard rain ; and yet these birds 

 drudge on to no purpose, from summer to summer, without 

 changing their aspect or house. It is a piteous sight to see 

 them labouring when half their nest is washed away, and 

 bringing dirt " generis lapsi sarcire ruinas" Thus is instinct 

 a most wonderfully unequal faculty ; in some instances so 

 much above reason, in other respects so far below it ! Martens 

 love to frequent towns, especially if there are great lakes and 

 rivers at hand ; nay, they even affect the close air of London. 

 And I have not only seen them nesting in the Borough, but 

 even in the Strand and Fleet Street : but then it was obvious, 

 from the dinginess of their aspect, that their feathers partook 

 of the filth of that sooty atmosphere. Martens are by far the 

 least agile of the four species ; their wings and tails are short, 

 and therefore they are not capable of such surprising turns, 

 and quick and glancing evolutions as the swallow. Accord- 

 ingly, they make use of a placid, easy motion, in a middle 

 region of the air, seldom mounting to any great height, and 

 never sweeping along together over the surface of the ground 

 or water. They do not wander far for food, but affect sheltered 

 districts, over some lake, or under some hanging wood, or in 

 some hollow vale, especially in windy weather. They breed 

 the latest of all the swallow kind : in 1772, they had nestlings 

 on to October twenty-first, and are never without unfledged 

 young as late as Michaelmas. 



As the summer declines, the congregating flocks increase 

 in numbers daily by the constant accession of the second 

 broods : till at last they swarm in myriads upon myriads round 

 the villages on the Thames, darkening the face of the sky as 

 they frequent the aits of that river, where they roost. They 

 retire, the bulk of them I mean, in vast flocks together, about 

 the beginning of October ; but have appeared of late years, 

 in a considerable flight, in this neighbourhood, for one day or 

 two, as late as November the third and sixth, after they were 

 supposed to have been gone for more than a fortnight. They, 

 therefore, withdraw with us the latest of any species. Unless 

 these birds are very short-lived, indeed, or unless they do not 

 return to the district where they are bred, they must undergo 

 vast devastations somehow, and somewhere ; for the birds that 

 return yearly bear no manner of proportion to the birds that 

 retire. * 



* Inscrutable are the ways of Him who is the director of all things. 

 He has, in his infinite wisdom, so nicely regulated the increase of animal 

 life, that there shall be no superabundance. But for this, there would 



