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REPORTS ON THE STATE OF SCIENCE. — 1920. 



the deviations from year to year are so great as to prohibit any reliance being placed 

 on the results of the customary analysing processes applied to a single year's record. 

 In fact, instead of the results from all analyses for the same constant being equal, 

 the apparent amplitude for one year is sometimes more than ten times that for 

 another year, while the apparent lags are sometimes distributed through more 

 than three quadrants. 



We also give some figures relating to three different analyses of tidal currents at 

 Smith's Knoll (Lightship off Norfolk). In 1911 six weeks' observations were 

 analysed, but in 1912 and 1913 only two weeks' observations were analysed. 



Tidal Heights at Bombay (Apollo Bandar) 1906-1915. 



