IN THE MONTH OF FEBRUARY, 1842. 165 
Chart 2 represents the features of the storm more fully developed. The snow has 
increased, dissolving into rain on its southern border; the cloudiness is still farther 
extended; the blue sky is mostly supplanted. In the eastern states, the pressure of the 
atmosphere has risen .4 inches above the mean under the influence of the westerly 
wind; and in the west, the barometer has fallen .4 inches under the influence of the 
storm. 'The temperature is generally near the mean, except in the east, where the ther- 
mometer fs still 10° below the average. ‘The winds are becoming more uniform and 
steady. Throughout a circle of nearly a thousand miles diameter, the prevalent tendency 
of the winds is inward towards the storm, with a slight disposition to circulate around this 
centre against the sun. By the morning of February 16, the storm had made sensible 
progress towards the east, and become much elongated. ‘The greatest depression of the 
barometer in the centre of the storm is now .6 inches, and increases in each direction, 
standing .2 inches above the mean on the front of the storm. Here, also, the thermo- 
meter stands at its mean height; while, a little in advance of the centre, it stands 5° above 
the mean; a little behind the centre it stands at the mean, and in the rear 10° below 
the mean. ‘The same law as just stated, holds true with regard to the winds. There is 
a prevalent tendency inward, with a disposition to circulate around the centre. 
Chart 4 shows the storm still farther advanced. The area of rain is now nearly equal 
to that of the snow. The cloudiness in the rear of the storm is contracted into narrow 
limits, and blue sky covers nearly the entire United States. The barometer in the cen- 
tre of the storm now stands .8 inch below the mean. It stands near the mean in the 
rear of the storm, and evidently as high and perhaps higher on the front. The thermo- 
meter near the middle of the storm stands 10° above the mean, and in the rear 20° below. 
The winds are now generally very strong and steady, exhibiting in a still more striking 
manner the phenomenon already alluded to, that,of an inward tendency, with a disposition to 
circulate around the centre in a direction contrary to the sun’s motion. On the morning 
of the 17th, only a part of the storm is included within the limits of the United States, 
and the observations are confined to one side of its centre, which is much to be regretted, 
as its violence was still increasing. The barometer stands 1.00 inch below the mean in 
the middle of the storm, and at the mean in the rear. The thermometer stands 20° above 
the mean in the middle of the storm, and 20° below the mean on the rear, The same 
law of the winds holds true. In the north-western part of the United States, cloudiness 
was commencing, which was followed by another storm about equally remarkable with 
the one we are considering. In the following table, column second shows the amount 
of snow at the different stations, and column third the total amount of water, including 
snow and rain. 
SNOW. | WATER. | | SNOW, | WATER. | 
STATION. STATION. | 
Inches. Inches. | Inches. | Inches. | 
St. Louis, Snow, "C01 1 | Daw oe 5 aes 
Fort Winnebago, Snow, 0.4 || Fort Gratiot, Snow, 06 | 
Indianapolis, 0.018 || Marietta, 1.5 
Cincinnati, (Ray) 4.75 0.51 | Hudson, : 0.30 | 
— mat illiams,) : i 0.51 | ta rar ; | 
| y; a) | eadvi le, 
Columbus, 5 || Erie, 2 .167 | 
a eer ETO Ye RE NENDNONTENON ET 
