THE RIVER MERSEY. 



35 



had been opened through the shoals, intermediate between the Zebra and 

 Victoria Channels, having a minimum depth of 9 feet. 



The Banks. — No material change had taken place in any of the banks, 

 except that Little Burbo had been sunk below low-water level, with sound- 

 ings of from 2 feet to 5 feet, and that the bulk of Taylor's Bank and Jordan 

 Flats had been slightly reduced. 



Western Channel. — The eastern portion of the Rock Channel had been a 

 good deal contracted, principally by enlargement of the foreshore at New 

 Brighton. The average area in 1854 had been reduced 200 yards, or about 

 four per cent, per annum. The average depth had remained pretty stationary. 



Meteorological Phcunomena. — From the Warrington tables, it appears that 

 the rain-fall at Warrington had been — 



In 1852=41-46 inches. 

 1853 =28-25 „ 

 1854=27-18 „ 



From the tables printed with Mr. Osier's paper " On the Self- registering 

 Anemometer and Rain-Gauge in the Liverpool Observatory," published in 

 the Reports of the Association for 1855, p. 128, it appears that the rain-fall 

 at Liverpool had been — 



In 1852=31-53 inches. 

 1853=22-42 „ 

 1853=22-11 „ 



It will be observed that there is a very great difference between the 

 records for Liverpool and Warrington, the proportionate difference for each 

 year being very similar; and it is to be noted that it is the fall in the up- 

 country which is most likely to produce changes in the channels of the river, 

 through the agency of freshes. 



The Liverpool tables for the first time furnish definite information upon 

 the phaenomena of wind. From them it appears that the point out of the 

 whole sixteen from which the wind blows for the greatest number of days 

 throughout the year is S.S.E., and therefore it has been said by Mr. Osier 

 that in Liverpool the prevailing winds are from that point. In the absence 

 of explanation, or without very careful explanation of the tables, this state- 

 ment is likely to convey an erroneous impression : if, instead of comparing 

 point with point, we take the five points from N. to W. both included, we 

 find that in 1854 the winds from this quadrant blew for as much as half 

 the year, or for as many days as the winds from all the other points taken 

 together. In the other years there is a preponderance of the same points, 

 though not to the same extent. The relative hourly velocity for the winds 

 from this quadrant is also greater than for those from other points. 



If reference be made to the table (p. 142, vol. 1855) which exhibits the ex- 

 treme pressure of the wind in pounds per square foot,and the greatest horizontal 

 motion of the air between any one hour and the next following hour, for all 

 the gales during the four years of which observations are recorded, in which 

 the pressure has reached \5 pounds per square foot, it will be observed that 

 in thirteen cases in which the velocity has exceeded fifty miles per hour, four 

 of them were from S. of W., attaining velocities respectively of 71, 70, 53, 

 and 51 miles per hour; the remainder being from W. to N.W., having 

 velocities varying from 51 to 5& miles per hour. It may also be observed 

 that of eighteen cases in which the pressure exceeded twenty pounds on the 

 square foot, four of them were from the S. of W., the pressure being respect- 

 ively 42 lbs., 42 lbs., 23 lbs., and 22 lbs. ; the remainder ranged from W. to 

 N.W., and had pressures varying from 21 lbs. to 43 lbs. 



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