166 MIGRATION AND DISTRIBUTION 



He often talked and wrote to his friends of the birds 

 he heard passing over Cambridge on dark nights. 

 " Owing to my practice of writing late at night these 

 thirty years or more, with a sliding pane in my window 

 let down, I have observed that they come from the N.E. 

 in a straight line — ^flock after flock." 



If he was unwilling to formulate a theory of migra- 

 tion, he was always eager to point out the fallacy in any 

 of the new ideas or to show the absurdity of ancient 

 superstitions. Of these latter, the hardest to die was 

 the theory that birds hibernated in a torpid state, and 

 he declared that on this point only in connection with 

 this subject could we boast ourselves to be clearly wiser 

 than our ancestors. But year after year, instances of 

 this curious belief presented themselves to him either in 

 public print or in private communications. 



I forget all about Kalm's story ; but it is really not 

 so uncommon for people to be able to persuade them- 

 selves of the truth of anything they want to believe, as 

 Mr. Gladstone was said to do. I was once almost 

 stumped by a story about torpid Swallows till provi- 

 dentially a witness presented himself and explained the 

 whole thing by stating that they were Bats ! 



I had a bit of fun once in Nature with the late Duke 

 of Argyll, who pretended that his brother-in-law (I think 

 it was) had seen Swallows or Martins dug out of the banlv 

 of the Tigris or Euphrates. I doubt whether the Duke 

 believed it, but he felt bound in honour to stand up for 

 his informant. 



Elliott Coues was much inclined to believe in torpidity, 

 perhaps did believe in it, but was ashamed to declare his 

 belief, for he had enough physiological knowledge to 

 know that such a thing is all but impossible in a bird. 

 No one has ever traced or ever will trace the bounds of 

 human credulity ; for the last ten days or more people 

 have been writing letters to the Times, nearly all 



