mysterious and not understood by the 

 wisest people. 



The material of a feather consists of 

 cells that push each other out to their 

 destination. They change their forms as 

 they travel along, and their colors and 

 degrees of hardness change with their 

 going. They are composed of about 

 the same stuff that makes horns and 

 hoofs. Your finger nail is like a 

 feather in its growth and composition. 

 It is mostly albumen with some lime in 

 it. Albumen is the substance which 

 makes the white of eggs. 



When the Mexican motmot trims his 

 two tail feathers with his beak, he 

 merely makes diamond cut diamond. 

 The material of the cutting instrument 

 is the same as that of the thing cut, 

 only somewhat harder. 



When you consider how a feather 

 grows by pushing out its cells you must 

 wonder at the intelligence which guides 

 the cells to change their nature so as 

 to form the quill, the shaft, the after- 

 shaft, the barb, the barbules, and the 

 little hooks which hold them together. 

 More than this is the cause for admira- 



tion seen in the regular change of pig- 

 ment contained in the cells, so the 

 feather shall have its beautiful colors 

 and accurate markings. 



Along with the materials of the 

 feather is carried a little oil which 

 turns the water from the duck's back 

 and gives the feather its gloss. It 

 is thought by some that the fading of 

 feathers in museums where mounted 

 specimens are exposed to the action 

 of light is largely due to the loss 

 of this delicate oil. No enterprising 

 Yankee has come forward yet with a 

 patent for restoring this oil and giving 

 back to the thousands of musty and 

 dusty skins in our museums their origi- 

 nal brilliancy. 



Every one wonders at the way feath- 

 ers keep their shape instead of getting 

 hopelessly ruffled. The little hooks 

 which hold the barbules together are 

 exceedingly strong and flexible. They 

 will yield and bend, but never break. 

 Even when torn apart from their hold 

 they can grasp again so as to restore 

 the injured feather to its former shape. 



VISION AND SCENT OF VULTURES. 



REV. R. T. NICHOL. 



To the Editor of Birds and All Nature : 



Sir: Are you not mistaken in the 

 assertion in your October number that 

 vultures, carrion-crows, etc., have such 

 keen scent that they can detect car- 

 casses and offal at a very great dis- 

 tance? 



I was under the impression that 

 Wilson* had decided this forever, and 

 proved conclusively that their appar- 

 ently miraculous power of discovering 

 their proper food, was due to keenness 

 of vision, and not of the sense of smell. 

 The following extracts may be new 

 to some and interesting to all of your 



*When 1 said "Wilson" above I find I was slightly 

 mistaken. I remembered reading- it long- ago in 

 the first edition I possessed of this writer's works— 

 the little four--volume set edited by Prof. Jameson for 

 "Constable's Miscellany," Edinburgh, 1831. and taking 

 •down the book now, which I have not opened for years, 

 I find the passages in question (Vol. iv, pp. 245 et seq.) 

 form part of an appendix drawn from Richardson 

 and Swainson's "Northern Zoology," and that the 

 real authority is Audubon. 



readers: Under the head "VidtJir aura, 

 Turkey Vulture," etc., I find: 

 "Observations on the supposed power 

 which vultures such as the turkey 

 vulture, are said to possess of scent- 

 ing carrion at a great distance. 

 "It has always appeared to us unac- 

 countable that birds of prey, as vul- 

 tures, could scent carcasses at such im- 

 mense distances, as they are said to 

 do. We were led to call in question 

 the accuracy of this opinion, on recol- 

 lecting the observations of some trav- 

 elers, who have remarked birds of prey 

 directing their course towards dead 

 animals floating in the rivers in India, 

 where the wind blows steadily from 

 one point of the cotripass for months 

 in succession. It was not easy to con- 

 ceive that the effluvium from a putrid 

 carcass in the water, could proceed in 

 direct opposition to the current of air, 



163 



