66 , JOURNAL AND PROCEEDINGS. 



that it has been compared to a fall of dust in an unoccupied room. 

 No better proof of this can be given than that an examination of the 

 abyssal mud disclosed the presence of an appreciable proportion of 

 meteoric iron, the product of those falhng stars which dissipate 

 themselves on entering our atmosphere. Professor Geikie says, in a 

 recent geological lecture in Scotland : — " To learn that mud gathers 

 there so slowly that the very star-dust forms an appreciable part of 

 it brings home to us as hardly anything else could do, the idea of 

 undisturbed and slow accumulation." 



An interesting memoir by M. Tschermak, of the University of 

 Wissenschaften, was published in 1875, on the source of meteoroids, 

 and a paper on his memoir was, a few years ago, read before the 

 Royal Irish Academy by Mr. Robert Ball. Tschermak claims a 

 volcanic source in some celestial body. Mr. Ball follows the theory 

 further, and by able reasoning shows that, if ejected from the planets 

 or asteroidSj there would only be a chance of one in 50,000 of them 

 faUing on the earth. In the early stage of our own earth's history, 

 long anterior to life, when mighty convulsions were rending it, 

 colossal volcanoes may have existed with explosive energy enough to 

 drive missiles upwards with a velocity which would carry them far 

 enough from the earth to a point where they would continue to 

 move in orbits round the sun, crossing at each revolution the point 

 of the earth's track from which they were originally discharged. If 

 this were the case, there are now doubtless myriads of those pro- 

 jectiles moving through the solar system, the only common feature 

 of whose orbit is that they all intersect the track of the earth, and, 

 it and they now and then meeting, the point of intersection would 

 be marked by the descent of a meteorite. This theory was hinted 

 at by Dr. Phipson, in a work published by him in 1866, and Mr. 

 Lawrence Smith, another later writer on the subject, inchnes to the 

 same view. No volcano now exists with explosive energy enongh 

 to eject fragments that could constitute future meteoroids, and if 

 such ever did exist, it could only be in the early stages of the earth's 

 history. 



Another, and an ingenious theory advanced by Professor 

 Newton, of Yale College, and one meeting with general acceptance 

 is, that meteoroids are fragments of or attendants on a comet, and 

 in a lecture of his in 1879, he scientifically endeavors to prove 

 this. Speaking of the recurring November meteoric showers which 



