448 EF. Loomis—Barometric Gradient in great storms. 
nearly the same, in computing the gradients by the formula, 
the latitude of each center was taken to be 45°. 
he upper part of Plate I gives a graphic representation of 
the numbers in the preceding table, and is constructed in the 
same manner as the lower figure on the same plate: At the 
center of low pressure the barometer stands at 28°7 inches; and 
at the center of high pressure the barometer stands at 30°9 
inches, showing a range of pressure amounting to 2°2 inches. 
The distance from the low center to the high center is 22-075 
degrees, and the entire figure represents a length of 44°15 de- 
grees, or 3046 English miles. — 
Upon comparing table I with table II, the first fact which 
attracts our attention is that the gradients in the two cases do 
Atlantic Ocean, violent storms have a much greater geograph- 
ical extent than they have over the United States. For the 
United States the average diameter of the area of low pressure 
(below 80 inches) in the case of violent storms is 23 degrees, OF 
1587 English miles. Over the Atlantic Ocean it is 29°3 degrees 
or 2022 miles, which is 27 per cent greater than for the United 
rounding air from a great distance. The greater resistance 
experienced by the air in its motion over the land than over 
the water, may perhaps partially explain the less extent of the 
low area in the United States. But we find that in the interior 
of Europe violent storms have nearly the same geo raphical 
extent as over the Atlantic Ocean. This is shown ff 
meyer’s Weather Charts and by the International Weather 
aps. Over the western portion of Europe, near the Atlantic 
ae n, the barometer frequently falls as low as 720, am 
_ Sometimes it falls even lower than this at a great distance from 
