places — tlie destntctiou to tlie crops of Minnesota appearing to be no greater 

 than on tlie lands adjacent to either side of the Ohio. 



It was occasioned, evidently, by a storm extending from the pole to the 

 equator, bringing down the cold air from the arctic regions. Here the early 

 morning air was pleasant, but that of the middle of the afternoon and evenino" 

 very disagreeably cold for several days. At night when the wind fell, the heat 

 of the ground warmed the air so as to preserve all the eastern States north of 

 Washington from frost ; but the northwestern wind, during the day, brought 

 down the cold air, so disagreeable, in the afternoon. But in the northwestern 

 States, which lay more directly in the track of the storm, the heat of the soil 

 was insufficient to shield against frost. To what extent the northwest wind 

 continued blowing during the nights in these States we have no present informa- 

 tion to determine. 



But one of the peculiarities of this, as of most frosts, was its " variousness," 

 as generally termed. And, from all accounts, it is this which will show a much 

 lighter damage than at first generally supposed. It is proper, therefore, that 

 the cause of this should be examined into. 



Every person has observed, in the spring of the year, those peculiar warm 

 bodies of air which have a forward motion from the south to the north, and a 

 spiral one of greater or lesser force. Some will make the dried but unfallen beach 

 leaves rustle from the combined powers of these two forces, whilst others pass 

 among them without moving the leaves. Now, these bodies of warm air are 

 brought directly from the south by the wind. The pressure of the colder air 

 on all sides gives them this rotary motion, and serves to keep them from mixing 

 immediately with the colder air. Just as in meeting a rise in a large river, 

 spots of muddy water are first met with ; these gradually become more numerous 

 and larger, until the dear water is seen but in spots, and presently all is muddy. 

 So it is Avith bodies of heated or cold air as they are forced into a mass of atmos- 

 phere of different temperature. There are warm spots and cold ones of greater 

 or lesser extent according to the intensity and duration of the storm. 



There are other causes also serving to increase this "variousness." Cold air, 

 being heavier than warm, settles in the lower places, such as in the sink basins 

 of the cavernous limestone regions, and in valleys bordering on creeks and 

 rivers. In the basins the corn is killed, whilst out of them it often is not. In 

 the bottom lands, where the frost would be most intense, the air is kept above 

 the freezing point by the warm exhalations of fog from the creeks and rivers. 

 So, in a like manner, the air from large bodies of water, as the great lakes, pro- 

 tect large districts from frost. A high country is above the frost line ; hence 

 the greatest injuries of the recent frosts will be found between the bottom allu- 

 vial lands and the highest lands. 



Between all these causes we believe it will be found that the recent frosts, 

 although very severe and destructive, have not done that injury which was gen- 

 erally believed, nor can the extent of the damage be ascertained now ; much 

 of that sujiposed to be ruined, as sorghum, indicates an internal life, from its 

 peculiar nature, that will throw out other flowering stems and blades sufficient 

 to mature the plant, but not, probably, to effect such an elaboration of the sap 

 as will render it perfect enough to make sugar. But especial inquiries relative to the 

 injury sustained by the foil crops have been made in the circular for September, 

 when the extent of the injury will be much better known than now. 



The extent of the frost was great, embracing the States of 3Iinnesota, Wis- 

 consin, Michigan, Ohio, Indiana, Illinois, Iowa, parts of Kentucky, and the 

 eastern portions of Missouri and Kansas, doing but little injury in these portions. 

 Sufficient cold to produce frost appears to have been from four to five days' 

 duration in the more northern portions, and a day or two less in the southern. 

 In its course across the lakes and over the heated earth the cold wind appears 

 to have been so much mitigated that when it reached the States of New York, 



