Observations of the Weather in Maderia, Made by Dr. Thomas Heberden, and Communicated by William Heberden, M. D. F. R. S.

(i.e.) 'The Pic has put his little hat on;' and look on it as a certain sign of rain. During the 6 or 7 years, that I lived in the villa of Oratava, as I had a continual sight of the Pic, I have several times observed the above phenomenon, and do not remember one instance, in which the prediction of rain failed. LVIII. Observations of the Weather in Madeira, made by Dr. Thomas Heberden, and communicated by William Heberden, M.D. F.R.S. Read Febr. 6, 1752. THE thermometrical observations are made with Fahrenheit's thermometer, and the calculations deduced from two observations daily; at seven o'clock in the morning, and at three in the afternoon. The same method of calculation is to be understood of the barometer. The rain fell thro' a funnel 15 inches in diameter. The Lefté, Levant, or hot winds, are very troublesome. The remedy is, to keep ourselves within-doors. October 1749, comparing 2 of Fahrenheit's thermometers together, one of them exposed on the north side of my house to the open air, the other within-doors, the difference was as follows: | Hour | Therm. within-doors | Therm. exposed to the air | |------|---------------------|--------------------------| | Lefté, Oct. 20. | 10 | 73 | 81 | | | 12 | 76 | 82 | | | 4 | 77 | 77 | MADEIRA ### Madeira, Anno 1749. | Month | Barometer | Thermometer | |-----------|-----------|-------------| | | Mean Height | Greatest Height | Least Height | M. H. G. H. | L. H. | | March | 29.81 | 30.2 | 29.8 | 64.66 | 70 | 61 | | April | 30.075 | 30.2 | 29.8 | 60.7 | 68 | 64 | | May | 29.55 | 30.1 | 29.6 | 66.53 | 69 | 65 | | June | 30.017 | 30.15 | 29.75 | 68.75 | 72 | 66 | | July | 30.027 | 30.1 | 29.95 | 74.58 | 75 | 72 | | August | 30.013 | 30.1 | 29.95 | 75.07 | 77 | 74 | | September | 30.054 | 30.15 | 29.85 | 76.53 | 78 | 72 | | October | 29.841 | 30.1 | 29.7 | 72.2 | 77 | 68 LW| | Novemb. | 29.68 | 30.1 | 29.55 | 68.6 | 73 | 67 | | December | 29.675 | 29.9 | 29.4 | 64.9 | 68 | 62 | ### Anno 1750. | Month | Barometer | Thermometer | |-----------|-----------|-------------| | | Mean Height | Greatest Height | Least Height | M. H. G. H. | L. H. | | January | 29.195 | 29.8 | 29.4 | 64. | 68 | 62 | | February | 29.692 | 29.75 | 29.5 | 63.8 | 67 | 61 LW| | March | 29.12 | 29.65 | 29.3 | 66.5 | 71 | 61 LW| | April | 29.285 | 29.4 | 29.1 | 66.45 | 68 | 65 | | May | 29.775 | 29.9 | 29.5 | 66.25 | 68 | 65 | | June | 29.875 | 30.1 | 29.5 | 69.06 | 72 | 6 | | July | 29.887 | 29.95 | 29.8 | 73. | 75 | 71 | | August | 29.386 | 30.1 | 29.75 | 75.4 | 78 | 72 | | September | 29.915 | 30.05 | 29.7 | 74.93 | 77 | 72 | | October | 29.797 | 29.9 | 29.5 | 73.87 | 77 | 70 | | Novemb. | 29.875 | 30.05 | 29.55 | 70.825 | 76 | 67 | | December | 29.843 | 30.2 | 29.5 | 66.27 | 74 | 64 | N. B. LW signifies a Levant or hot wind, in Feb. and March. An Account of the Quantity of Rain, which has fallen in the Island of Madeira. | Anno | 1747 | 1748 | 1749 | 1750 | |------|------|------|------|------| | January | 20.525 | 8.600 | 2.097 | 7.150 | | February | .485 | 10.958 | 1.203 | 1.771 | | March | 4.339 | 5.241 | .932 | 1.123 | | April | .528 | .722 | .777 | .039 | | May | .353 | 5.290 | 1.087 | | June | 1.321 | .420 | .113 | .226 | | July | .200 | | | .176 | | August | .018 | 2.700 | | .003 | | September | .540 | .810 | .855 | 1.682 | | October | .010 | 3.303 | 1.512 | 6.601 | | November | 5.181 | 2.654 | 3.059 | 5.611 | | December | 7.351 | 1.500 | 6.527 | 1.882 | The years 1749 and 1750, were such dry years, that the corn was destroy'd, and the fruit-trees suffer'd much, particularly the peach-trees, the fruit either falling to the ground, whilst green, or, if it remained longer on the tree, being full of white worms.