TJie Great Storm of March 11-U, 1888. 37 



THE GREAT STORM OF MARCH 11-14, 1888. 



A Summary of the remarks made by Brigadier-General A. W. 

 Greely, Chief Signal Officer of the Army. 



This storm is by no means as violent as others which have 

 occurred, in the eastern part of the United States. It is noted^ 

 however, as being one in which an unusual amount of snow fell, 

 which, drifted by the high winds caused by the advance of an 

 anticyclonic area in rear of the storm depression, did an enormous 

 amount of damage to the railways in Massachusetts, southern 

 New York, and New Jersey. 



The storm centre was first noticed in the North Pacific on 

 March 6th ; whence it passed southeast from the Oregon coast to 

 northern Texas by the 9th. The centre instead of maintaining 

 the usual elliptical form, gradually shaped itself into an extended 

 trough of low pressure, which covered the Mississippi and Ohio 

 valleys during the 10th. On the morning of Mai'ch 11th the bar- 

 ometer trough extended from Lake Superior southward to the 

 eastern part of the Gulf of Mexico ; in the northern section over 

 Lake Superior, and the southern part, over Georgia, distinct 

 centres, with independent wind circulation, had foi'med. 



The northern storm centre moved northeastward and disap- 

 peared, while the southern centre moved slowly eastward, passing 

 off the Atlantic coast near Cape Hatteras. The pressure on the 

 afternoon of March 1 1th was about 29.07 at the centre of both 

 the northern and southern storms, but during the night of the 

 11 -12th the pressure decreased in the southern storm centre, and 

 the area instead of continuing its easterly direction moved almost 

 directly to the north, and on the morning of March 12th was 

 central off the New Jersey coast. 



The causes which underlie the decrease of pressure and conse- 

 quent increase in the violence of storms are, as yet, undetermined. 

 The theory of " surges," that is, atmospheric waves independent of 

 the irregular variations consequent on storms, has been urged by 

 some, and especially by Abercromby, as the cause of the deepen- 

 ing of depressions in some cases or of increasing the pressure in 

 other cases. It is possible that un'der this theory a " surge," pass- 

 ing over the United States to the eastward, as its trough became 



