[ 6x8] 
Madeira, Anno 1753* 
Barometer Thermometer. 
M. H. 
G. H. 
L. H. 
M. H. 
G.H. 
].. H 
January 
29.9O4 
3°. i 7 
29.6 
63.I29 
66 
6l 
February 
2 9 -S >3 3 
3°. I 7 
29.6 
67.946 
7 ° 
6l 
March 
29.943 
30 - 1 ? 
29. y 
66.967 
69 
64 
April 
29.921 
3 0 * 1 
29.7 
6 f . 3 l 6 
68 
6 3 
May 
29.896 
3 ^ 
29.8 
66.7OO 
69 
6 5 
June 
29.988 
30.05 
29.8 
{ 6 p .6 
7 2 
68 
Collecting the relpe&ive fums of the daily heights 
of the inftruments throughout the' year, and extract- 
ing the mean altitude, I find, 
The mean altitude of the barometer for each day, 
is ... 29.91 y inches. 
Of the thermometer, 68°. 91 8. 
The 'greateft barometrical variation, during four 
years and four months, has been 9 tenths of an inch, 
■viz. from 29.3 to 30.2. For altho’ in April 1771. 
the mercury flood at 29.1, 1 find, by a note in my 
diary, that feme air having infinuated itfelf into the 
tube, I judg’d the mercury to hand 3 tenths of an 
inch lower than it ought. 
The greateft thermometrical variation, during the 
Said time, has been ao° ; viz. from 6o° to 8o° : But it 
may be obferv’d, I never knew it rife fo high but 
once ; occasion'd by a very ftrong lefte or levant wind; 
the extreme height, without fuch an accident, being 
never more than 78°. 
N. B. It may be neceflary to advife, that my ob- 
servations are made in the city of Funchal. 
The 
