318 Intelligence and Miscellaneous Articles. 



tests made between 1868 and 1872, and are now at our disposal ; 

 and although the results of these numerous observations have not 

 as yet been all analyzed, or even compiled, yet in many special cases, 

 and for limited periods, this has been done ; and from these we are 

 justified in stating the following as facts : — 



" 1. All the hues in India are affected by natural currents. 



" 2. From more than 10,000 observations it has been established 

 that the prevailing flow of these currents between any pair of sta- 

 tions is as of a copper-current from the east to the west ; but which 

 is the true direction, or that of maximum intensity, and, further, 

 whether there is only one such direction, has not been computed 

 as yet. 



"3. The strength of the natural current in one and the same line 

 is very variable. 



"4. The direction of the natural current in one and the same 

 line, though also variable to a certain extent, is yet far more 

 constant than its strength, and out of a number of observations 

 there is generally a marked preponderance of currents flowing in 

 the same direction. 



"5. The variation in strength and direction of the natural currents 

 in parallel lines of the same length is far more uniform than might 

 have been expected, considering the many accidental influences to 

 which long overland lines are exposed. 



"6. The prevailing direction of the natural current in any line is 

 generally also the direction of the maximum current observed ; but 

 this is not the case invariably. 



" These general facts point to one probable conclusion — namely, 

 that ' earth-currents ' do permanently exist in the lines of India, 

 though they are often, and under certain circumstances even much, 

 obscured by many other causes, of commensurate magnitude, but 

 more unstable and accidental in character. 



"For example, the two railway lines between Bombay and Madras, 

 one of which is very perfect in insulation, while the other is quite 

 the reverse, both exhibit a copper-current flowing permanently 

 from Madras towards Bombay ; and this fact, having been ascer- 

 tained from a large number of tests, extending over a considerable 

 period, and made from both Madras and Bombay, proves that the 

 cause is a general one with respect to time, and that the method 

 and place of measurement do not influence the direction of the 

 current observed. Further, as one of the wires is used for the 

 through traffic towards Bombay, while the other is used for the 

 through traffic towards Madras, and as both circuits are worked 

 with copper-currents, the natural currents, which flow in the same 

 direction in the two wires, certainly cannot be due to the polariza- 

 tion of the earth-plates or of faulty places in the lines. The ave- 

 rage electromotive force in these wires is about 4*5 Daniells ; and 

 maxima of 15 and 20 Daniells are occasionally reached. 



" I consider it therefore established that ' earth-currents ' do per- 

 manently exist in the lines of India, their general drift being from 

 east to west, and that we should be now justified in establishing a 



