RED- FRONTED SWALLOW. 567 



of wonder. Five or six, or more feet down the chimney, does 

 this httle bird begin to form her nest about the middle of May, 

 which consists, Hke that of the house-martin, of a crust or shell 

 composed of dirt or mud, mixed with short pieces of straw, to 

 render it tough and permanent ; with this difference, that, 

 whereas the shell of the martin is nearly hemispheric, that of 

 the swallow is open at the top, and like half a deep dish : this 

 nest is lined with fine grasses, and feathers, which are often 

 collected as they float in the air. Wonderful is the address 

 which this adroit bird shows all day long, in ascending and 

 descending with security through so narrow a pass. When 

 hovering over the mouth of the funnel, the vibrations of her 

 wings acting on the confined air occasion a rumbling like thun- 

 der." The materials of which the nest is composed, as well as 

 its form, vary according to circumstances. Thus, in August 

 1834, I observed several nests of this species stuck beneath the 

 eaves at the end of an outhouse on the farm-steading of Gran- 

 ton in Dumfriesshire. They varied considerably in form and 

 size. Those in corners were of an irregular roundish shape, 

 rectangular above, where they were fitted to the angle, con- 

 vex in front, and having on one side at the top a semi- 

 circular aperture, of which the beam formed the upper part. 

 They were externally composed of pellets of friable earth, 

 which had been applied in the state of mud ; within the 

 outer layer, of a crust of cow and horse dung; and internal- 

 ly of a quantity of straw and feathers of domestic fowls, A 

 nest found on a beam in a shed at Gorgie Tan works near Edin- 

 burgh, had its external part formed of pellets of cow's hair and 

 earthy matter, cohering pretty firmly, but not agglutinated, and 

 disposed in the form of a shallow cup without the bottom, that 

 part having been formed by the plank. Straws were rudely 

 disposed within the crust, and the lining was composed of a 

 great number of large feathers of ducks and domestic fowls. 

 In general, the nest is open at top, when not fastened under a 

 beam or in a corner. The eggs are four or five, and difter con- 

 siderably in size and form. They are usually of an elongated 

 oval, rather pointed, ten-twelfths long, seven-twelfths in breadth, 

 white or reddish- white, marked all over with scattered dark red 



