August 3, 1883.] 



SCIENCE. 



135 



wampum beads, the remainder of the belt being in 

 dark purple. This probably belonged to the gens 

 bearing the name of the calumet, and whose office it 

 was to prepare and present the grand calumet in all 

 the solemn asemblies. 



The effect of the isolation of this tribe upon its 

 langua:;e i^ also an interesting and important study. 

 Through the courtesy of Superior Anloiiie and Pere 

 Burtin, I have obtained access to an invaluable col- 

 lection by the French missionary Marcoux, which will 

 furnish Mohawk synonymes for a dictionary of the 

 six Iroquois dialects, for which thirty thousand words 

 have already been gathered. Eiiminnie Smith. 

 203 PaciOc .\vc., .Tcraey City. 



Many snakes killed. 

 The number of snakes killed near this city during 

 the late overflow of the Nemaha River is almost be- 

 yond belief. They were driven by the water from 

 the botlom-lands to the higher grounds, and espe- 

 cially to the embankments thrown up across the 

 bottom for the Burlington and Missouri and the 

 Missouri Pacific railways. It is estimated that more 

 than three thousand snakes were killed within a mile 

 of this town. They were chiefly garter snakes: but 

 water moccasons, blue racers, and rattlesnakes were 

 also killed. A horse was confined in a pasture sur- 

 rounded by a wire fence in the overflowed district, 

 and, when released, it was found that several snakes 

 had taken refuge in the long hair of his mane. Since 

 my residence here, 1 have travelled nearly all over 

 this county, a portion of the time engaged in geo- 

 logical explorations; yet, up to the lime of the pres- 

 ent June overflow. I had failed to see half a dozen 

 snakes all told. The overflowed district along the 

 Nemaha would not average over a mile in width; and 

 it is astonishing where so many snakes found hiding- 

 places. Undoubtedly, nearly all the snakes in this 

 county are confined to the creek and river bottoms. 

 Stephen Bowebs. 



Falln City, Ni'b., July 10, 1883. 



Swallows in Boston. 



Has any one seen a swallow in Boston this sum- 

 mer ? The old proverb says, ' One swallow does not 

 make a summer.' Have we a summer and not one 

 swallow '? Carl Reodots. 



Singular lightning. 

 On the evening of July 4, 18S:S, I noticed some 

 lightning which differed from any that I have previ- 

 ously seen. About sunset a mass of very threaten- 

 ing clouds, accompanied by heavy rain and lightning 

 of the usual character, rose in the north-west, and, 

 following an easterly course, passed a little to the 

 northward, giving us a few drops of rain from its 

 ragged southern edge. It was quickly succeeded by 

 a comparatively thin cloud-stratum, — apparently the 

 after-birth of the main storm, — the course of which 

 was directly overhead. During the passage of this 

 cloud, rain fell briskly but not heavily for perhaps 

 half an hour, and rather frequent flashes of lightning 

 preceded and followed the first sprinkle. Owing to 

 my position on the eastern side of a large building, 

 I could not see the earlier flashes; but their light, 

 thrown on the walls of neighboring houses, was 

 noticeably rose-colored. At length, however, one 

 came that could be accurately noted. It passed di- 

 rectly overhead, forking into five fine, thread-like 

 lines of vivid yellow light. Each line was distinctly 

 zig-zagged with sharp though not prominent angles. 

 The divergence of the lines was nearly regular, but 

 the outer pair branched at a greater angle than the 



inner three. The relative divergence was similar to 

 that of the outstretched fingers of a human hand; 

 but a still more accurate idea may be given by the 

 following sketch. 



The flash above described was followed, in a few 

 minutes, by a second one, .apparently similar, but 

 less satisfactorily noted. After this the rapid pas- 

 sage of the storm carried the lightning beyond my 

 limited space of observation. 



I may add that none of the lightning from this 

 cloud seemed to come to the earth, its course being 

 on an apparently horizontal plane. The accompany- 

 ing thunder was unusually deep and grand. 



WiLLi.YM Brewster. 



Cambridge, Mju*8. 



Deflective effect of the earth's rotation. 



In Science for March 2 (No. 4), Mr. W. M. Davis 

 says, "A correct knowledge of the deflective effect 

 of the earth's rotation is generally accounted the 

 result of studies made within the last twenty-five 

 years." 



This correct knowledge, he says, is still disputed 

 by some authors. 



By transferring the axis of rotation to the tangent 

 plane on which the body is supposed to move, and 

 resolving the earth's rotary motion into two motions, 

 — one around the meridian of the tangent plane, and 

 the other around a vertical to that plane, — it is easily 

 seen, without recourse to the equations of motion, 

 that the angular motion of the tangent |)lane with 

 respect to a fixed plane will depend upon the angular 

 rotation of the earth and the sine of the latitude of 

 the tangent plane; from which it follows that the de- 

 flective force is the same, in whatever direction the 

 body is supposed to move on any given tangent plane. 



But in resolving the actual motion into two mo- 

 tions, respectively around the vertical to the tangent 

 plane and around the meridian of that plane, we 

 have neglected the effect resulting from the latter, — 

 a consideration of which woulil have introduced an- 

 other term, containing a function of, and therefore 

 varying with, the cosine of the angle contained be- 

 tween the meridian and the line of projection of the 

 moving body; we have also neglected the effect of 

 the centrifugal force resulting from the motion of the 

 body, which is a minirniun when the motion is in 

 the meridian, and a maximum when at right angles 

 to tlie meridian, and therefore also varies with the 

 cosine of the angle contained between the meridian 

 anil the line of projection of the moving body. When 

 the velocity is considerable, both these terms become 

 sensible; and therefore the deflective force is least 

 when the body moves in the meridian, and greatest 

 when the motion is at right angles with the meridian. 



This conclusion is in conflict with the 'correct 

 knowledge' above alluded to; viz., that the deflec- 



