34 



SUME MAGNETIC OBSERVATIONS IN MÉXICO 



(From a letter to the Editor of Tr.rrestrial Wagnetiam). 

 I ' ■ 



I have the pleasure to communicate the following data that I obtai- 

 ned in an expedition to the northern frontier in the month of July of last 

 year: 



In Juárez City, I did not determine D and S because of the electríc 

 railways. In Jiménez and Zacatecas, I and Z are wanting as the dip circle 

 was somewhat injured in transportation over bad roads. AU the observa- 

 tions were made in the field outside the cities. In my former letter I 

 mentioned to you that the valué of / that I am obtaining in Cuajimalpa 

 is something like 20' higher than the last that was determined here bef ore 

 the installation of the electric railways and which I attribute to some de- 

 fect in the dip circle that I am using (Fauth, model of Kew). 



Tacubaya, México, June 4, 1903. 



M. Moreno y Anda. 



a Between 9 and 11 a. m. 



b Mean of observations at 8 a. m. and 2 p. m. 



c At 10 a. m. 



