224 Meteorological Observations. 



METEOROLOGICAL OBSERVATIONS. 

 Kept at Wilmington, Del., by Henry Gibbons, M. D. with Prefatory Remarks, 



Meteorology, is a branch of science, which, hitherto, in this 

 country, has not received its proper share of attention. It is 

 true, that many observations on temperature, and the incidents 

 of the weather, are daily made and published ; but the task of 

 the observer mostly ends with the mere collection of those facts. 

 In this, as in other departments of Natural Science, facts are 

 principally useful as they lead to inferences — to principles. We 

 should not only gather them with industry and precision, but we 

 should arrange and compare them, so as to exhibit, as nearly as 

 possible, their relation to each other, and draw from them every 

 corollary which is consistent with sound reasoning. For exam- 

 ple, I find, by examining the register of the weather, so as to 

 ascertain the relation between electrical phenomena and the 

 weight of the atmosphere, that a thundergust seldom occurs, un- 

 less the barometer has sunk below a certain point. I also dis- 

 cover, that an aurora borealis is mostly followed, within a week, 

 by easterly winds, and very frequently by a storm from the same 

 quarter. I further observe, that this phenomenon was exhibited 

 thirteen times in the summer and autumn of 1830, but only five 

 times in the corresponding seasons of the present year. From 

 this, I infer that the frequent or rarer appearance of the northern 

 lights, may possibly furnish some index of the severity or mildness 

 of the subsequent winter. — Were the considerations I have pre- 

 sented, carefully kept in view, the science of meteorology might 

 become extremely useful, in its application to the foretelUng of 

 atmospheric changes. 



So far as I have had an opportunity of examining, the greater 

 part of the tables of temperature, contained in the public jour- 

 nals of the United States, at least of the middle states, are more 

 or less deficient or erroneous, owing to an improper situation of 

 the thermometer, from which the observations are taken, the 

 improper time of making the observations, or some other cause. 

 Very generally, these tables exhibit an annual temperature, 

 several degrees higher than the correct average. The ther- 

 mometer is probably suspended where there is not a free circu- 

 lation of air, or in a place exposed to the reflected rays of the 

 sun. Hence we often find in the newspapers accounts of tern- 



