270 



TRANSIT OF VENUS, 1874. EGYPT. 



The initials C, A D, and M are, respectively, those of Messrs. Criswick, 

 Downing, and Maunder, Assistants of the Royal Observatory. Mr. Criswick 

 is adopted as standard. The corrections applied to the " clock-slow " ob- 

 tained by Messrs. Downing and Maunder are respectively + O03 and 

 Oil. These are the quantities determined from a discussion of the 

 whole of the observations taken by these observers during the year 1S74. 

 See Greenwich Observations for 1874, page lii. 



The adopted values of the Royal Observatory Sidereal Standard Clock slow 

 are as follows : 



These values are used (see Table II.) to infer the error of the chrono- 

 meter C. Frodsham 3205, at Porthcurno. 



TABLE II. DETERMINATION of the ERROR of the Mean Solar Chronometer 

 C. FRODSHAM 3205, at PORTHCURNO, on GREENWICH MEAN SOLAR TIME, by 

 exchange of GALVANIC SIGNALS between GREENWICH and PORTHCURNO. 



