A. MATHEMATICS AND ASTRONOMY. 61 



Cadiz. A time-ball is established at Cadiz, but we have 

 no information of the time at which it is dropped. 



Neuchdtel. An extensive system of electrically controlled 

 clocks and of time-signals radiates from this observatory, for 

 the purpose of giving the true time to the chronometer and 

 watch makers, and for the public convenience. Several towns 

 participate in this. 



AFRICA. 



Cape of Good Hope. Time-ball at 1^. 



ASIA, ETC. 



Madras. A time-ball is dropped daily from the Custom- 

 house at 8*" 20 57.3^ Madras mean [civil] time = 15^ Green- 

 wich mean time. The time of the flash of the eveniiioi; sfun 

 is noted at the observatory, and published at tlie Master-In- 

 tendant's ofiice the next morning. 



Batama {Java). There is a time-ball dropped at Batavia 

 mean noon, and also one at 1^ 7 12.5^ Batavia mean time = 

 18^ Greenwich mean time. Calcutta. Daily time-gun. 



Vladivostok. There is a branch of the Russian Hydro- 

 graphic Office established at Vladivostok, and a naval officer 

 obtains the time daily with a transit instrument, and keeps 

 his clock reofulated for the benefit of navigators. 



AUSTRALIA. 



Melbourne. A time-ball is dropped daily (Sundays ex- 

 cepted) at 1^ m. s. t. The time is also given from the same 

 place at 8^ (P.M.) by the obscuration of a powerful light at 

 two minutes before 8^^ : the instant of reappearance of the 

 light is the true time. The errors of these two signals on 

 any day are published on the next day in the newspaj^ers. 



Sydney. A time-ball is dropped daily. 



Newcastle. A time-ball is dropped daily by signals from 

 Sydney. 



SOUTH AMERICA. 



Rio de Janeiro. We have no entirely satisfactory ac- 

 count of the details, but we are informed that a time-ball is 

 dropped daily at noon. 



Buenos Ayres. The Observatory of Cordoba sends elec- 

 tric signals to Buenos Ayres for tlie regulation of clocks ac- 

 cessible to ship-masters. 



