DIASTROPHISM AND THE FORMATIVE PROCESSES 495 



pletion, and the work of aggregation into granules probably fol- 

 lowed closely after. The conditions for the escape of the molecules 

 that remained free would also be favored by the smallness of the 

 bodies and the condensation of the precipitated portion. The 

 escape of the free molecules would leave the precipitate aggregates 

 with such internal motions as were inherited from the previous 

 states. The last previous stage was that of a Brownian mixture 

 whose internal motions did not differ radically from those of true 

 gases, but the growing inelasticity must not be overlooked. The 

 laws that would have governed the cloud of precipitates when first 

 formed would not have differed very widely from gaseous laws. 

 The inherited motions had, however, as we have seen, introduced 

 a tendency toward an orbital development. In general the pre- 

 cipitated particles in a Bpownian mixture so conditioned would 

 not fall directly to the center even if an open path were provided 

 for them; on the contrary they would pursue elliptical orbits 

 about the center. By interference they would undoubtedly at 

 length reach the center but only through a delayed course with 

 consequent dissipation of energy. 



Now the units^ — which at the start were perfectly elastic mole- 

 cules — would by the precipitating and aggregating processes grow 

 into granules many million times more massive, and in the process 

 would become increasingly inelastic. By this change in the nature 

 of the unit there would have arisen a wide gap between even the 

 heaviest of the free molecules and the average spherules, granules, 

 or chondrules into which the precipitates passed. The velocities 

 of the latter would have been of so much lower order that there 

 seem no good grounds to doubt that the main mass of the latter 

 would be susceptible of control and continued concentration under 

 conditions that would be quite prohibitive of control as free 

 molecules. 



The very process of molecular escape tended in itself to increase 

 the gap between the units prone to escape and those prone to 

 continue their concentration. In every collision from which a 

 molecule escapes by rebound there is an equal reaction of the 

 partner in collision in the opposite direction. The escaping mole- 

 cule usually has the lesser mass and to give escape the rebound must 



