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TRANSIT OF VENUS, 1874. EGYPT. 



of (a) and (c), and the results (?) and (m) from those of (e) and (g) ; these are 

 similarly affected with any irregularity of rate of the chronometer Reid and 

 Sons 1207 itself. That is to say, the results (b) and (i) depend, the former 

 on the steadiness of rate of C. Frodsham 3205, the latter on the steadiness of 

 rate of Reid and Sons 1207, and the mean of the two values may be adopted 

 for the error of Reid and Sons 1207 at this epoch. Similarly for (d) and (&), 

 for (/) and (I), and for (h) and (m). 



The errors of the chronometer Reid and Sons 1207 used in Table VI. 

 depend on the numbers contained in the fifth and sixth columns of the pre- 

 ceding table. 



TABLE VI. DETERMINATION of the ERRORS of the MEAN SOLAR CHRONOMETER 

 HEWITT 890, at ALEXANDRIA, on GREENWICH MEAN SOLAR TIME, by ex- 

 change of GALVANIC SIGNALS between PORTHOURNO and ALEXANDRIA, through 

 the SUBMARINE CABLE of the EASTERN TELEGRAPH COMPANY. 



