114 NATURAL HISTORY [Birds. 



but excellently fitted for swimming ; the feet, when the stroke 



is given, extend to their whole breadth, but when it is to be 



fetched these fold up and become little thicker than the leg. 



All parts of these birds are excellently fitted for making their 



way through the water with great speed ; the head is taper, 



the bill small, &c. but this is so excellently described by the 



pious author of the Wisdom of God in the Creation, that I 



shall give it in his own words: " The bodies of the colymbi, 



" duckers, or loons, are admirably fitted and conformed for 



" diving under water, being covered with very thick plumage, 



" and the superficies of their feathers so smooth and slippery, 



" e that the water cannot penetrate or moisten them, whereby 



" their bodies are defended from the cold, the water being 



" kept at a distance, and so poised that by a light impulse 



" they may easily ascend in it ; then their feet are situated in 



" the hindmost part of the body, whereby they are enabled, 



" shooting their feet backwards, and striking the water up- 



" wards, to plunge themselves down into it with great facility, 



" and likewise to move forwards therein ; then their legs are 



" made flat and broad, and their feet cloven into toes, with 



" appendant membranes on each side, by which configura- 



" tion they easily cut the water* and are drawn forward, and 



" so take their stroke backwards ; and besides, I conceive, 



" that by means of this figure, their feet being moved to the 



" right and left hand, serve them as a rudder to enable them 



" to turn under water, for some conceive that they swim 



" easier under water than they do above it. How they 



" raise themselves up again, whether their bodies emerge of 



