584 



NATURE 



\_April 2 1, 1881 



greatest difference in elevation in the State would be 

 represented by a vertical height of one inch. The hori- 

 zontal scale of the cut is sixty-two miles to the inch. 



The map represents only the grand outlines of surface 

 as obtained from railroad profiles, and barometrical 

 measurements. The dotted lines on the map are lines of 

 equal variation of the magnetic needle : thus, on every 

 part of the line marked iS', the needle points 8° east of 

 north, &c. These lines are drawn to represent the objer- 

 vations already made, and show in a general way the 

 variation of the needle in the State. The map also shows 

 that there is a marked relation between the direction of 

 these lines and the contour of the surface. It cannot be 

 said that it shows what this relation is, but it is probably 

 due largely to the deriection of the stream lines of the 

 earth current sheet, caused by unequal conducting 

 power. This explanation necessitates the existence of 



looped areas in certain regions in the State, the existence 

 of which is already indicated by the determinations. The 

 loop in the 7^ 30' line, with its inclosed minimum, is 

 probably complicated with the iron deposits in that region 

 of the State. 



Three stations in the Missouri valley have been inad- 

 vertently omitted in the cut. One of these (CorroUton) 

 lies on the 8^ 30' line, a few miles north of the river. 

 Another (Glasgow) lies on the river a little south of east 

 from CorroUton. The third (Columbia) lies just east of 

 the S" line, and about south-ea^t from CorroUton. A 

 fourth station omitted, is nearly due east of the southern 

 terminus of the S" line, and just outside the 7^ 30' loop. 

 The other stations, represented by the small circles, are 

 shown on the cut, and an inspection of the map will show 

 the weight to be given to diflerent parts of these lines. 

 At stations situ ited at points of abrupt curvature of the 



lines, the observations have been repeated at various 

 localities in the region, untd it was clear that no minute 

 local effects existed. 



The value in the Iron Mountain region is the mean of 

 many hundreds of determinations made with a solar 

 compass by Pumpelly and Moore in 1872. This region 

 is in the east part of the 7' 30' loop. In the western 

 iron-field, which is nearly coincident with the 7° oval, our 

 observations were repeated at various points (the aim 

 being to avoid iron deposits) without finding any local 

 action. 



In conducting the survey, a magnetometer belonging 

 to Washington University was used, but the dip circle 

 and declinometer were kindly furnished by Prof. J. E. 

 Hilgard of the U.S. Coast and Geodetic Survey. Thus 

 far the survey has been conducted wholly on private 

 means, in which we have been aided by the railroad 



companies, and by citizens of St. Louis. A Bill providing 

 for the completion of the survey is now before the Legis- 

 lature of the State. Francis E. Xipher 



PRIMITIVE MARRIAGE CUSTOMS'^ 



THE chief object of Mr. Fison's recently published 

 memoir on Karailaroi marriage, descent, and relation- 

 ship, is " to trace the formation of the e.KOgamous inter- 

 marrying divisions which have been found among so many 

 savage and barbaric tribes of the present day," and to 

 show that what Mr. Morgan calls the punaluan family, with 

 the " Turanian " system of kinship, logically results from 



I " Kamilaroi and Kurna! : Group Marriage, and Relationship, and 

 iMarriage by El ipement : also the Kuinai Tribe, their Customs in Peace and 

 War." Uy Lor.mer Fison, M.A., and A. W. Howitt, F.G.S. With an 

 Introduction by Lewis H. Morgan, LL.D. (George Robertson: Melbourne, 

 18S0.) 



