OF ARTS AND SCIENCES. 19 



in showers with moderate or light southwest winds, sometimes veering 

 to northwest shortly afcer midnight and during the early morning 

 at many points ; a tolerably well-marked progression is found from 

 central Vermont at 2^ central New Hampshire at 3^ to 4^ south- 

 eastern New Hampshire and eastern Massachusetts from 4^* to G*"; 

 but as additional showers are confused with the main one, and as the 

 time of occurrence was unflivorable to reporting, little can be said of 

 the storm. It is noteworthy, however, that a good number of observers 

 made detailed records even at three and four o'clock in the mornine:. 

 The rain was hardly felt south of AVorcester and Boston, although 

 thunder was heard some distance farther south. 



The temperature during the early storm was between 60° and 70''. 

 The morning was fair, with southwesterly winds, and the warmth in- 

 creased to 80° or 85° at noon. Clouds then began to gather, and be- 

 tween 13'' and 14'^ developed into a long, narrow thunder-storm, 

 stretching over one hundred and fifty miles, from northwestern Con- 

 necticut to Cape Ann in northeastern Massachusetts. The intensity 

 of the storm varied along this line, as seems to be generally the case, 

 but was nowhere very severe ; at some stations, all the elements of 

 the storm were moderate; at others, the rain, beginning gently, became 

 heavy for a short time, and the heavy shower was preceded by a short- 

 lived high wind from the northwest, and accompanied by a rapid fall 

 of ten or fifteen degrees in the temperature. The electric action was 

 inconsiderable at all stations. Northern Massachusetts and the States 

 beyond had practically no thunder-storms in the afternoon. Starting 

 from the beginning here defined, this storm extended southeastward, 

 and reached eastern Connecticut, Rhode Island, and southeastern Mas- 

 sachusetts about 16^ but was nowhere reported on the southern coast. 

 The parallel lines representing its rain-front at 14^ lo^ and IQ^ are 

 distant only about 20 miles, if measured N. N. W. to S. S. E. at right 

 angles to their length ; but as nearly all observers agree in giving the 

 storm a decided easterly motion, it would seem that the velocity should 

 be measured very obliquely to the rain-front, in which case it may 

 have been as much as 40 or more miles an hour. Although present- 

 ing the well-marked linear extension characteristic of thunder-squalls, 

 the clouds of this storm cannot be well classified from the records that 

 we have other than as heavy rain clouds. The several types described 

 under the storm of July 9 do not appear here. The observer at 

 Provincetown, Mass., reports high stratus clouds moving from the 

 west-southwest before the lower cumulo-stratus clouds came with the 

 storm from the northwest. 



