August 31, 1883.] 



SCIENCE. 



265 



the invalid is after. It is true that carbonic 

 acid has a way of accumulating in low and 

 unventilated recesses ; but there are cellars, 

 crevices, and deep and narrow valle\s in the 

 highlands as well as on the lower levels. As 

 well recommend thin soup to the hungry man 

 as to advise the sick man, whose one lung must 

 do the duty of two, to breathe thin air. 

 Should he climb the mountains to Leadville, 

 he will be warned awa^- by tlie inhabitants of 

 that city, who will inform him, in the rude 

 poetry of the mines, that a healthy man has 

 to fan the air up into a corner in order to get 

 enough for a breath. 



The atmosphere is not necessarily dry at a 

 great altitude, as some suppose, nor damp in 

 the lowlands. There are lofty swamps and 

 low deserts. The mountain peaks, according 

 to the poet, milk the clouds ; and in some parts 

 of the world the mountaineer is more sure of 

 his daily rain than of his daily bread. Mount 

 Taylor, in New ^Mexico, is called the ' ^Mother 

 of rain ' bj" the imaginative Indians. On the 

 other hand, the deserts of California, which 

 are below the level of the sea, are so dry, that, 

 in the language of the plains, the jack-rabbit 

 has to pack his water with him when he goes 

 upon a journej-. 



As to the thousands who have been rescued 

 from death by the ' pure, rarefied, and dry 

 atmosphere ' of Minnesota, this is a matter 

 of town talk, which impartial observation does 

 not confirm, and which there is no census to 

 denj-. In this connection I would challenge 

 the champion of the most celebrated sanita- 

 rium for consumptives to produce a list of the 

 patients who have ' got better ' under his 

 notice, and I will match against him an equally 

 honest observer from some undistinguished 

 and unpretentious and confessedly unhealtliy 

 locality, whose proportional record of improve- 

 ments will be equally favorable. AV''hy, then, 

 should the sick man become a wanderer, as 

 he certainly- will if he once starts in chase of 

 the ignis fatuus of a climate cure ? 



Frank D. Y. Carpenter. 



LETTERS TO THE EDITOR. 

 Prehensile feet of the crows. 



In nos. Ifi, IS, a,\\A 20 of Science are communica- 

 tions by different writers on the intelligence of crows, 

 suggested by one of mine in no. 1.'!. I beg to add 

 one more, concluding what I have to say on this 

 subject. 



All seem agreed as to the intelligence of these 

 birds; but few, I find on in()iiiry, have seen them 

 seize or carry objects in their claws. Yet no amount 

 of negative testimony should invalidate my observa- 

 tion on the Italian bird, when taken in connection 



with the further evidence to be given. We all look 

 at nature piecemeal ; and it is certainly unreasonable 

 to assume that one is in error because he claims to 

 have seen through his pin-hole something which an- 

 other lias not observed through his. 



I agree with the doubters, that crows ordinarily use 

 their bills, and not their claws, in seizing and carrying 

 their food. In confirmation of what I claim to have 

 seen, I will adduce similar instances, noticed by 

 others as well as myself, in the Corvidae. I cannot 

 positively assert that the bird I saw was C. corone: 

 it might have been C. cornix, possibly C. frugilegus, 

 hut, at any rate, a crow, for it had the flight, the 

 proportions, the color, the voice, and the boldness of 

 these birds. 



As to crows not nesting among rocks, this is gen- 

 erally true of the American crow (C. Americanus); 

 but the European C. corone. a larger and more soli- 

 tary species, prefers the sides of steep rocks, ,-is also 

 does the hooded C. cornix. Both the American .and 

 European ravens often nest in inaccessible cliSs, and 

 so do the rooks. 



To begin with the largest. I have seen C. corax 

 in Iceland holding and carrying in its claws fish- 

 heads from the beaches, and, when disturbed, from 

 one barren cr.ag to another, — an object too large and 

 too heavy to be conveniently carried in the bill, and 

 too precious to be left behiml where food is so scarce. 

 I have seen C. carnivorus, in the winter wilderness 

 of Lake Superior, carrying in the same way what 

 looked like a squirrel or rabbit. It is well known 

 that both these birds, when wounded, will strike 

 savagely with their claws, like a bird of prey; which, 

 being perching birds, according to our classifications 

 they had no scientific right to do. 



Of the fish-crow (C. ossifragus), Wilson (Amer. 

 ornith., V. 27) writes, "their favorite haunts being 

 about the banks of the river, along which they usu- 

 ally sailed, dextrously snatching up u-ilh their claw» 

 [the italics are mine] dead fish or other garbage that 

 floated on the surfaee;' and, on p. 28 (op. cit.), "These 

 (a singular kind of lizard) the crow would frequently 

 seize ivith his clnwx, as he flew along the snrfiice, and 

 retire to the summit of a dead tree to enjoy his re- 

 past." Audubon {Orn. bioii., ii. 269) says the same. 

 Clark's Columbian crow is said to do the same thing, 

 and its claws are sharp and raptorial. 1 have seen 

 this species, along the shallows of the coast of North 

 Carolina, seize and carry off in its c/a(cs living fish 

 from the shoals over which it flew. 



Biiffon, Chenu, Wilson, and Nuttall allude to the 

 custom of capturing crows by fastening one on its 

 back, feet upward, on the ground: its cries bring its 

 companions to the rescue, one of whom is sure to be 

 seized and held by the claicx of the prisoner. 



For several summers I lived in the next house to a 

 tame and speaking crow, which often came in front 

 of the kitchen in quest of food. One day a half- 

 oaten ear of boiled corn was thrown to him. While 

 engaged in picking it, holding it by the claws, as is 

 the habit with the crows, he was disturbed by the 

 attacks of a barking terrier. Keeping him at bay for 

 a time by vigorous pecks, he finally tried to carry the 

 e.ir in his hill to a favorite perch in a low cedar. As 

 he seized it, first at one end and then at' another, the 

 leverage of the free end was such that it gave his 

 head and neck very uncomfortable twists. lie finally 

 perched upon the ear in defence of his food, and, 

 elincliing it tightly in his clawx, flew with it, in ray 

 ^ight, to his perch a few feet distant. 



"Mr. E. A. Samuels (author of the 'Birds of New 

 England') writes to me (Aug. 2, 18S3), "I have 

 known of Its seizing with one foot — and hopping 



