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it makes its way, and for stemming at the same time the force of 
the current ; for that no effort is required to keep its place below 
the surface, is what no one has said.” Mudie, who, as usual, 
theorises a good deal, says on the subject: “The difference of 
___ specific gravity between the bird and the water is indeed so trifling, 
that very little effort suffices to move it in any direction, upwards, 
___ downwards, or laterally.” At the same time I much doubt whether 
Mudie ever saw the Dipper in its native haunts, as his descrip- 
tion of it is a great deal more fanciful than truthful. 
The late Mr. J. K. Lord in an article in ‘Science Gossip” on 
the Belted Kingfisher, remarked that it did not swim or walk at 
the bottom of the water, as the Dipper did. This brought a letter 
from a correspondent, who was much surprised that Mr. Lord still 
believed in what he thought was an exploded doctrine ; and who 
backed up his letter by quoting Charles Waterton’s arguments, and 
advised Mr. Lord to read Waterton’s essays on Natural History, and 
then he (Mr. Lord) would not tell amateur naturalists the absurd 
story that the Dipper could walk underneath the water. 
This brought answers from several correspondents who had 
seen the Dipper perform this seemingly impossible feat. One of 
them quoted the opinion of the late Charles St. John a most 
accurate observer, who said, “though the fact has often been 
doubted, it certainly runs and scratches up the stones while at the 
bottom in search of food.” These letters brought another from 
_ correspondent No. 1, who said his argument had not been answered, 
and proceeded to give three reasons against the so-called walking :— 
Ist. It is well known that the bodies of all birds float in the water. 
2nd. He was convinced that birds are obliged to make great 
exertions with their wings and feet, in order to reach the bottom, 
_ 3rd. When they reach the bottom, the force which carried them 
there ceases to act, consequently they must rise again. These 
arguments clearly proved to correspondent No. 1 that the so-called 
walking was impossible. Another correspondent, in reply to this, 
_ wrote :—“ Can birds walk under water? The question has as yet 
_ been evaded, rather than answered. It is easy to heap up argu- 
‘ments showing that it cannot be done. Many such theories have 
