590 The Sinithsoniaii Institution 



attraction. The velocity in the (hyperbolic) orbit was 9^ 

 miles a second, approximately. As the meteor moved in 

 its path, successive explosions took place, and it was found to 

 be necessary to divide the orbit into three parts and to de- 

 termine three sets of elements corresponding to the parts. 

 The perigeal distances in the three sections were, for exam- 

 ple : 40,007 miles, 3974 miles, 3995 miles, respectively. The 

 meteor's nearest approach to the earth's surface was about 39 

 miles, which point corresponds to the end of the second sec- 

 tion of its path. From this point onwards its height above 

 sea increased. One of the employees of the United States 

 Lake Survey describes the meteor (near Lake Huron) to 

 have been nearly as large as the moon, at first. In a moment 

 it had burst and a piece " fell directly to the ground near the 

 place of observation, setting fire to the vegetable matter around 

 it ; the fire was put out, but the piece could not be found." 

 In Washington City the meteor was observed as two bodies 

 near together, "each as bright as Venus when close to the 

 earth." Its rate of motion was comparatively slow, so that 

 one observer in New Jersey wrote: "The movement of the 

 meteor appeared to be not much more rapid than the flight 

 of an eagle I think I could have kept sight on it with a gun 

 throughout its course." 



In reading the various reports from persons scattered over 

 the Middle and Western States, it is remarkable to note the 

 names of the observers. An extraordinarily large proportion 

 of these names are well known to all Americans. All the 

 astronomers — Young, Bond, Peters, Bartlett, Mitchel, Lyman, 

 Newton, Swift, and others — appear to have seen it; there 

 are reports from many professors in colleges; and a great 

 number of the remainino- observers are well known in one 

 way or another. It is seldom that the data for such an 

 orbit are derived from reporters of such trained intelligence. 



