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Reports on Special Researches 



Table 19 B. Results of Horizontal-Intensity Comparisons at Ike Porto Rico Observatory, 1910. 



Table 19 C. Results of Inclination Comparisons at the Porto Rico Observatory, 1910. 



'AH values are referred to E. I. pier; station E. I. = station No. 1 9'. 2. 



Referring the mean results to I. M. S. (see p. 273), we obtain: 



(19) I. M. S.- Porto Rico (Cooke magnetometer No. 31 referred to Cheltenham) = +0'.5 (1910). 



(19a) I. M. S.- Porto Rico (Cooke magnetometer No. 31 referred to Cheltenham) = -0.000977/(1910). 



(]%) I. M. S.- Porto Rico (Schulze inductor No. 1 referred to Cheltenham) = + I'.O (1910). 



NO. 20. POTSDAM OBSERVATORY, GERMANY. 



All observations by the C. I. W. observer (Mr. J. C. Pearson) for the comparisons at 

 the Potsdam Observatory, were made on what is called "Pier No. 5." There was no 

 exchange of stations as the Observatory had alread^y made tests showing that station 

 differences were negligible. The values given for Potsdam depend on the final determina- 

 tions of the base-hnes. 



