35 



Back to 1840 the liighest mean readings have been in the 

 years — 

 18;H when it was 29-984 in. 1874 when it was 29-910 in. 



1858 „ 29-920 in. 1878 „ 29-990 in. 



1859 „ 29-890 in. 1880 „ 2!)-925in. 

 So that there has been no instance, back to 1840, of so high 



mean readings for the three months ending March, the nearest 

 approach was in 1878, when it was 29-90. 



Diagram (Plate 2) show in ff the average mean daily pressure 

 of t/ie atmosphere at B/ackheath, at the height o/ 150 feet above the 

 level of the sea, o?i every day from October 1, 1881, to May 31, 

 1882. 



The diagram shows that the mean daily pressure of the 

 atmosphere till October 8th was above the average by 0-4 in.; 

 from the 9th to the 14th it was below by 0-12 in. daily; then 

 for five days it was above by 0-15 in. daily; from the 20th to 

 the 25th it was below by 0-26 in. daily; and it was 0*26 in. 

 daily above till the end of the month. On the first four days in 

 November it was below by 0-06 in. daily ; from November 5th 

 to the 24th it was mostly above, the mean averaging for these 

 20 days 0-16 in. in excess of daily average ; then for four days it 

 was below by 0-49 in. daily; from November 29th to December 

 6th, it was upon the average 0-22 in. above ; then for six days 

 0*2 in. below ; then for three days 0-22 in. above ; from December 

 16th to 22nd it was daily 0-46 in. below; then for seven days 

 0-41 in. above, and on the last two days of the year it was slightly 

 below the average. 



Tiiey were below their average till the 6th day of January ; 

 on the 3rd day it exceeded 0-5 in.; the lowest reading throughout 

 the month at nearly every station took place on this day. The 

 average daily deficiency of pressure till the 6th was 0-23 in. On 

 the 7th day of January the reading was above its average, and 

 continued so till February 24th; with the exception of the 11th 

 and 15th days of February, on which days it was 0-07 in. below 

 its average on both days. The readings in January were very 

 remarkable, the average daily pressm-e from the 16th to the 19th, 

 both inclusive, was nearly one inch in excess over the average. 

 On the 18th the reading all over the country was remarkably 



