MASONRY OF THE CRESCENT SWALLOW 431 



iu the West, as comi^ared with their rather sporadic distribu- 

 tion iu the East, is thus readily explained. The great veins of 

 the West — the Missouri, the Columbia, and the Colorado, — 

 and most of their venous tributaries, returning the humors 

 from the clouds to their home in the sea, are supplied in pro- 

 fusion with animated congregations of the Swallows, often 

 vastly more extensive than those gatherings of the feathered 

 Sons of Temperance beneath our eaves, where the sign of the 

 order, — a bottle, neck downward, — is set for our edification. 



All are familiar, doubtless, with the architecture of these 

 masons — if any be not, the books will remove their ignorance. 

 But there are many interesting details, perhaps insufficiently 

 elucidated in our standard treatises. It is generally under- 

 stood that the most perfect nest, that is, a nest fully finished 

 and furnished with a neck, resembling a decanter tilted over, — 

 that such a " bottle-nosed " or " retort-shaped " nest, is the 

 typical one, indicating the primitive fashion of building. But 

 I am by no means satisfied of this. Remembering that the 

 Swallows are all natural hole-breeders, we may infer that their 

 early order of architecture was a wall, rampart, or breastwork, 

 which defended and perhaps enlarged a natural cavity on 

 the face of a cliff. Traces of such work are still evident 

 enough in those frequent instances in which they take a hole 

 in a wall, such as one left by a missing brick, and cover it in 

 either with a regular domed vestibule or a mere cup-like rim 

 of mud. It was probably not until they had served a long 

 apprenticeship that they acquired the sufficient skill to stick a 

 nest against a perfectly smooth, vertical support. Some kind 

 of domed nest was still requisite, to carry out the idea of hole- 

 breeding, a trait so thoroughly ingrained in Hirundine nature, 

 and implying perfect covering for the eggs ; and the indication 

 is fully met in one of the very commonest forms of nest, 

 namely, a hemispherical affair, quite a "breastwork" in fact, 

 with a hole at the most protuberant part, or just below it. The 

 running on of a neck to the nest, as seen in those nests we 

 consider the most elaborate, seems to merely represent a sur- 

 plusage of building energy, like that which induces a House 

 Wren, lor example, to accumulate a preposterous quantity of 

 trash iu its cubby-holes. Such architecture reminds me of the 

 Irishman's notion of how cannon are made — by taking a hole 

 and pouring the melted metal around it. It is the rule, when 

 the nest is built in any exposed situation. But since the Swal- 



