NIPHER MAGNETIC DETERMINATIONS IN MISSOURI, '8o. 333 



Magnetic Deter 7ninaiions in Missouri during the Summer 



of 1880. 

 Bj Francis E. Nipher. 



In the previous number of the Transactions* we have given a 

 report on magnetic w^ork done in 1878 and 1879. Tiie work of 

 these years was mainly confined to the northern and western parts 

 of the State. In 1880 the work was carried into south-east Mis- 

 souri. Advantage was taken of trips to adjoining States to make 

 determinations there. 



Following is a description of stations where observations have 

 been made. A much fuller description, with sketches and plat 

 of the ground on which the determinations were made, is in the 

 possession of the writer. The numbers of the stations are con- 

 tinued from previous reports. 



Station 32 b — ColUnsville, Madison Co., Ills. Observations in the 

 north corner of the yard (orchard) of O. B. Wilson. The schoolhouse 

 spire bears S. 76° 30'. g W. The ColUnsville work was repeated at a dif- 

 ferent station from that of 1879, as, according to the work of last year, the 

 declination at ColUnsville and at Washington (60 miles W.) was nearly 

 the same. The redetermination confirmed this result. It was further 

 confirmed by the subsequent work of the summer. Polaris observation 

 for meridian. At this station only the morning-mark reading was ob- 

 tained. 



Station iS d—Iowa City, lozva. On farm of Peter Nipher, in the 

 meadow 90 yds. S. of the S.E. corner of the house. Polaris obs. 



Station 18 c— the same station as that of 1879. The mark of 1879 

 was used. 



Station 33 — jiear Atalissa, Muscatitie Co., loixa. Lat. 4i°3S'.4;t 

 Lon. gi° 13'. g. On the farm of Mrs. Grace Aikins, on the N.E. qr. of 

 the N.E. qr. of sec. 2, tp. 78 N., r. 3 W. of the 5th prin. merid. In a small 

 slough a little W. of the house and midway between the house and the 

 Cedar Co. line. No evening mark reading. 



Station 34 — ?« Cedar Co., loxva. Lat. 41° 42'. 7; Lon. 91° 14. 'o- 

 On farm of Edmund Aikins, near the N.E. corner of S.E. qr. of sec. 20, 

 tp- 79. r. 3 W. In yard 70 ft. S. of the house and 50 from the road fence. 

 This station is marked by a sandstone set about 24 inches into the ground, 



* Trans. Acad. Sci. of St. Louis, vol. iv. No. i, pp. 81-101, 121-145. 



t These latitudes and longitudes have been determined by the Land Office map, as was 

 explained in the first report. This has been i riticised in a semi-public way. It is only 

 necessary to state that the writer does not consider this an accurate method of determining: 

 latitude ; but that it is sufficiently so for this magnetic survey is a matter which does not 

 admit of discussion. 



