14 



SCIENCE. 



[Vol. VII., No. 152 



cause of this equatorial wind-belt is probably the 

 lagging-back of the loosely cohering and adhering 

 atmosphere over the equatorial region, which has a 

 maximum motion of rotation from west to east of 

 about a thousand miles an hour. The equatorial 

 wind-current has a motion westward of from five to 

 ten miles an hour, but this is only relative to the sur- 

 face of the earth, since it has an absolute movement 

 eastward with the earth of perhaps 990 to 995 miles 

 an hour. 



The lagging- back of the atmosphere over the 

 tropical regions may be altogether due to its inertia, 

 or it may be in part the effect of friction with that 

 real but intangible medium which fills the interstel- 

 lar spaces, — the luminiferous ether. Whatever the 

 cause of the equatorial wind-current may be, its 

 importance in the physics of the globe cannot be ex- 

 aggerated. Among the other phenomena with which 

 it may be credited are the red sunsets which are now 

 generally believed — as stated by the editor of your 

 astronomical column — to be due to the projection into 

 this equatorial current of an immense volume of vol- 

 canic dust from Krakatoa, which has not only floated 

 many times around the earth, but has been widely 

 diffused north and south of the equator by the high 

 upper currents of air that flow from the equator 

 toward the poles, and constitute the other great 

 factors in atmospheric circulation. Along the ther- 

 mal equator the heated air is constantly rising, and 

 is replaced by the cooler and denser air flowing 

 along the surface from the north and south. This, 

 coming from regions where the rotation of the 

 earth is much less than at the equator, reaches 

 the torrid zone with a strong relative motion toward 

 the west, — going slower than the earth, — and 

 giving us the south-east trades of the southern side 

 of the equator, and the north-east of the northern. 

 The constant upward tendency of the air along the 

 heated zone would retard the descent of the dust, 

 and favor its suspension in the heaped -up mass of air 

 which flows northward and southward from the 

 equator. This air, which has an absolute eastward 

 movement with the earth of perhaps 990 miles per 

 hour, soon reaches a zone where the earth : s move- 

 ment is less than this, and where, with reference to 

 the surface, the movement is toward the north-east 

 in the northern hemisphere, and south-east in the 

 southern. This, as is known to many, but perhaps 

 not to all, of your readers, gives us the general drift 

 of the atmosphere over the United States. 



By the northward and southward flow of the 

 tropical and dust-bearing air, that dust may be dif- 

 fused over most of the earth's surface before it 

 settles. J. S. Newberry. 



New York, Dec. 28. 



Congenital deaf-mutism. 



The chief requisite to racial experiments is isola- 

 tion. A race of men is a breed, a stock, a strain that 

 has been isolated long enough to fix by inheritance a 

 number of characteristics. This isolation may be 

 cither geographical or social. Where caste prevails 

 and marriage is confined to groups, the characteris- 

 tics of each ^roup will l>e fixed and perpetuated. 

 This is social isolation, and tin result, is in the nature 

 of a race. At the time when there were fewer people 

 on the earth, and when the allurements to commerce 

 and the means of locomotion were not so numerous, 

 the present races of the world were fixed. 



Prof. A. Graham Bell has on several occasions 

 lately called attention to the formation of a race of 

 deaf-mutes by caste isolation and intermarriage. A 

 very interesting example of reaching a race of deaf- 

 mutes by geographical isolation has just come to my 

 notice. 



Lieut. H. T. Allen, U.S.A., lately engaged in the 

 exploration of Alaska, writes me as follows : — 



" On two tributaries of the Koukuk River, Konoo- 

 tenah and Nohoolchintnah, both emptying from the 

 south, and about seventy-five miles between mouths, 

 were two villages about twenty-five miles from the 

 respective confluences, the upper village 66°. 40' north, 

 150 .50 west. One village contained six males, the 

 other five ; and, of these eleven, four were deaf- 

 mutes. There was a woman w T ho could speak fairly 

 intelligently to her people, but could not hear. There 

 was also a boy who was a deaf-mute. The natives 

 said that the mutes had never been able to speak or 

 hear, and the sounds emitted had nothing in common 

 with the articulations of their relatives. I can ac- 

 count for the foregoing facts only by continued inter- 

 marriage, which is necessitated by their isolation. 

 Above the upper village there are no tribes on the 

 Koukuk River, none between the Nohoolchintnah 

 and Konootenah, and none for many miles below the 

 latter river. The men from these villages trade at 

 the station on the Yukon River, near the mouth of 

 the Tanandh. They claim to be Kleekots, but can 

 readily converse with the natives of the Yukon from 

 St. Yukon to Nulato." O. T. Mason. 



The English sparrow. 



Two years ago I published the fact in the Ameri- 

 can naturalist (September, 1883, p. 925), of the Eng- 

 lish sparrow^ having practically driven all the native 

 birds out of the beautiful parks of New Orleans, 

 when, even so long ago as that, this bird was to be 

 found there in numbers. I distinctly recollect hav- 

 ing seen them in Cheyenne, Wyoming, in 1877 ; so 

 that I think this pest has spread more rapidly than 

 some of the correspondents of Science are perhaps 

 aware. Of course, the most important point at issue 

 now, is to devise means for so reducing their num- 

 bers as to render them harmless in the future, or 

 better still, if possible, to exterminate them entirely. 



The methods suggested by Mr. Ralph S. Tarr (Sci- 

 ence, No. 149) are excellent so far as they go ; but I 

 would suggest a far more efficient weapon than the 

 shot-gun, for use in the city parks, recommended by 

 him. I refer to the collecting cane now in use by 

 many ornithologists in this country, with the seven- 

 chambered pistol attachment. I have an excellent 

 one by me now, belonging to the Smithsonian insti- 

 tution, and I will guarantee that I could kill 350 

 English sparrows with it in one day in New York 

 City, and keep it up for every day in the year, or 

 until their decreasing numbers reduced the average. 

 It possesses several highly important recommenda- 

 tions over the shot-gun : it makes scarcely any noise ; 

 the ammunition is cheap ; no danger is run of injur- 

 ing persons in a crowded city; and it would attract far 

 less attention. This weapon might be placed in the 

 hands of those who proved themselves experts in its 

 use, or any city police force. Other persons might 

 also be licensed to use it, who were willing to prac- 

 tise exterminating the birds for a reward. 



R. W. Shufeldt. 



Fort Wingate, N. Mex., Dec. 18. 



