LIVEEPOOL. 



205 



Table, in which we also give the maximum and minimum number of days 

 occurring during that period. 



The mean duration of Calm for the twelve years was 0"8 day per annum, 

 varying between 0*2 day in 1857 and 1"6 day in 1858. 



(138.) Notwithstanding that the results shown by the Liverpool Anemo- 

 meter are of the utmost value, and great labour and skill were exercised 

 in reducing them to a comprehensive form by the late Messrs. John 

 Hartnup, father and son, the able superintendents, yet they contain 

 evidence of the interference of land influences, as alluded to in (104), page 

 171. The self-recording anemometer showed that the winds from W.N.W. 

 and S.S.E. were most prevalent, whereas the prevalent direction in England 

 as a whole is from the West ; showing that the form of the valley of 

 the Mersey has much to do with diverting the normal direction of the 

 wind. Still the observations, as before stated, are most instructive and 

 important.* 



(139.) About the year 1865, the site of the Observatory at the Docks 

 being wanted for other purposes, the instruments were removed to a new 

 Observatory on Bidston Hill, on the opposite side of the Mersey, at an 

 elevation of about 190 ft. above sea level. The increased elevation, and 

 more open character of the situation, doubtless give the records of the 

 Anemometer more reliability. We are indebted to the courtesy of the 

 Astronomer to the Mersey Docks and Harbour Board for copies of the 

 Eeports issued from the Bidston Observatory, from which a similar Table 

 of the Winds recorded by the Anemometer has been drawn up. They 

 extend over a period of 20 years, from 1868 — 1887, and show a large 

 preponderance of winds in the S. W. quadrant over the previous records at 

 the Docks. 



The mean duration of Calm for the 20 years was 0'3 day per annum, 

 varying from 0*1 to 0*7 day per annum. 



* Report of the British Association, vol. xxv., pages 127 — 142 ; and, also, " Report of 

 the Direction and Strength of the Wind at the Liverpool Observatory, 1852 — 1863." It 

 is from these sources that the above facts and figures are derived. 



