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MAaNETIC OBSERVATIONS IN EHODESIA. 
By the Rev. E. Goetz, S.J., M.A., F.R.S.S.Afr. 
The observations recorded in this paper were taken in 1914 and 1916 
with the unifilar magnetometer, Nalder Bros. 135, and the Dover Circle 113. 
The observations are given without corrections as the corrections to these 
instruments have not been determined. In the reduction of the observations 
the constants determined at Kew in 1898 have been used throughout except 
in the case of the Moment of Inertia of the Collimator Magnet, of which the 
suspension apparatus had undergone some change in weight. A new value 
for the moment was determined in the course of the observations. For this 
three sets of determinations, each consisting of two sets of vibrations with 
loaded magnet enclosing a set with unloaded magnet, were taken. 
The three values for log. tt'^K were 3-38807, 3-38825, 3-38753, the mean 
of which, 3-38785, has been adopted for the determination of the magnetic 
moment. 
The Distribution Coefficient has been deduced separately for the 1914 and 
1916 observations. 
In the Barotseland Expedition the astronomical observations were taken 
and reduced by Mr. H. E. Wood, Chief Assistant of the Union Observatory. 
Time, latitude and longitude were determined by both sun and star series, 
and may be considered as very reliable, especially as three chronometers were 
used for the longitude determinations. 
In the Matabeleland Expedition, I took the time and latitude with a 
Claude prismatic astrolabe. The results for both were highly satisfactory, 
considering the difficulty of observations at night by one observer alone in 
the South African Veldt. 
The latitudes give a probable error of 1"-1 and the time observations an 
error of 0-18. As I had only one chronometer with me I give the longitudes 
to the nearest tenth of a minute only. These have been besides checked by 
reference to the Surveyor Oenerars map, the scale of which is of one inch to 
four miles. 
In the Barotseland Expedition I took only one set of magnetic observa- 
tions as we were rather pressed for time. A hitch in the transport 
arrangements gave me an opportunity of taking a set of declination readings 
at every quarter of an hour throughout a whole day at Katombora. 
In the Matabeleland Expedition I took two or three declinations at 
different times and a set of deflections between two sets of vibrations at each 
station. 
