132 On a Plan for properly observing Fire-ball Meteors. 



a slietch or drawing of the appearances before and after it burst, 

 or any other of its appearances. 



4th. Whether both the body and the tail burst; and how 

 many parts this bursting produced; and whether this happened 

 before or after it arrived at its greatest apparent altitude; the 

 length of the tail before the meteor liurst; and indeed every al- 

 teration of its length they observe; whether the meteor appear- 

 ed very faint at first, and gradually grew brighter, or appeared 

 very bright at once ; and whether it was extinguished suddenly, 

 or by degrees. 



5th. How long the appearance lasted. 



6th. Whether a sound or sounds (as of an explosion) was heard 

 some minutes after its disappearance, and how long, and from 

 what point of the compass they thought it came. 



7th. The bearing and distance of the place of observation 

 from the nearest market-town tsliould !)e put down. 



N.B. As sound moves only at the rate of thirteen miles in a mi- 

 nute, the observer should patiently wait for at least eight or ten 

 minutes, listening for the sound, for all meteors appear to be very 

 many miles indeed nearer to the observer than they really are. 

 Remarks. 



Curious persons may avail themselves of observations made 

 even by the most illiterate, by causing them to trace with a stick 

 the path which the meteor described in the heavens, according 

 to the best of their recollection. The observations would be bet- 

 ter made, if you accompany the person to the very spot where 

 he saw the meteor, for there the neighbouring objects, such as 

 roads, houses, or trees, will much assist his memory. 



The apparent altitudes of the meteor are best foMnd by a qua- 

 drant (a common wooden one of three inches radius divided into 

 degrees will suffice) which the person should direct to the points 

 in the heavens where the meteor appeared to him, if he saw it, 

 or even to such points where the illiterate jjerson above mention- 

 ed pointed. In like manner its bearings should be found by u 

 compass. 



To ascertain how long the appearance lasted, he shonld trrice 

 over its path in the heavens with its proper velocity, while another 

 person observes the time by a watch or clock that shows seconds; 

 or by the number of swings of a temporary pendulum made by a 

 musket ball or any small weight suspended by a string of 39 

 inches long from the centre of the ball or weight, which will 

 swing seconds. Without some such method as this, they will be 

 apt to estimate the time much longer than it is. 



It would be well if those persons who happen to see a meteor 

 would put down the time by their watch when it first appeared. 



