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same time have very Large diameters, if will be evident thai the near approach 

 of another massive body would lie sufficienl to cause great disturbance. 

 The attraction of the foreign body would cause the star to elongate, the 

 gravitational attraction at the ends of the longer axis would be decreased 

 and the highly compressed gases of the interior would cause great eruptions 

 toward the disturbing body and away from it. Even with the slight dis- 

 turbances to which our sun is subjected we have these outbursts of material 

 from the interior, by which material is thrown out al times, to distances of 

 a hundred thousand miles. 



If another star were to come within a few hundred thousand miles of 

 our sun this effect would be produced on a scale many times greater. While 

 the star was a considerable distance away these ejections of matter would 

 be less violent, increasing in violence as the distance decreased, and, what 

 is just as much to the point, they would be in a slightly different direction 

 as time went on. The first masses ejected would be drawn out of a straight 

 line and would eventually fatl back toward the sun, some of them striking 

 the surface and some of the 1 so far drawn to one side as to miss the surface 

 as they came back, in which case they would continue to revolve in elliptical 

 orbits about the sun. Those masses, thrown off a little later, would travel 

 farther and in slightly different directions, and would be diverted still more 

 and move in longer orbits. After a maximum disturbance was reached the 

 same process would go on with decreasing violence as the disturbing body 

 retreated into space. It has been shown that the masses thrown off which 

 did not go back to form part of the sun again, might under these conditions 

 form themselves into two spiral arms, the whole, of course, being in one 

 plane, as the motion of the two stars would be in a plane. That material 

 which did fall back into the sun would give to the part where it fell 

 a certain velocity of rotation, and we find in the sun a higher rate of rotation 

 for the equator than for any other part. The direction of motion of the 

 matter composing the arms of the spiral is not along the arms but across 

 them, each particle moving in an ellipse around the central mass. If 

 masses of different sizes were ejected, the large ones would tend to annex 

 the smaller ones in the immediate neighborhood, and the process before 

 described would result in a system of planets and satellites much as we have 

 in the solar system. 



We have this process still going on in a small way. The Earth attracts 

 to itself several million small particles every day and occasionally there is a 



