EDITORIAL 671 



envelope of water in the form of a deep and heavy atmosphere of 

 water gas, " forming an effective thermal blanket, Barrell continues: 



The effectiveness of the blanket depended upon the peculiarity of both 

 water gas and carbon-dioxide in being opaque to the slow vibrations of dark 

 heat, absorbing these near the bottom of the primitive atmosphere and re- 

 radiating them from higher levels as long, slow heat waves. Strong convection * 

 currents carried up these heated gases from the superheated base to the higher 

 levels of the atmosphere. There the chilhng condensed the water vapor into a 

 thick and universal canopy of cloud, boiUng up Uke thunder heads from below, 

 shedding continuously a downpour of acid rain, rain dissipated again into 

 v^apor as fast as the drops fell into the deeper and hotter strata of the at- 

 mosphere. The intensity of the vertical convection maintained a high electric 

 tension. Incessant flashes of lightning linked as with living fiery tentacles 

 the cloudy heavens to the lurid molten earth. Tremendous reverberations of 

 thunder, unsensed by mortal ears, shook the atmosphere in the world-wide 

 primeval storm 



During the more rapid growth-stages the molecular and dust-like matter 

 swept up by the earth settled like a never ceasing cloud of volcanic ash. The 

 planetesimals of sand and gravel size were swept up by the earth many millions 

 of times more abundantly than our meteors at the present time. Those 

 meeting the earth with the higher velocities were consumed by impact. Over 

 the hemisphere of night the otherwise invisible atmosphere above the cloud 

 canopy scintillated with incessant flashes of Ught and trails of luminous dust. 

 Bodies of larger size gave in their dissolution a stiU more brilliant display and 

 penetrated to greater depths. At longer intervals, with Titanic rush and roar, 

 a greater projectile, tens or even hundreds of miles in diameter, cleaved through 

 the canopy of cloud, leaving a tumultuous maelstrom behind, drove almost 

 unchecked through the dense atmosphere below, and, with world-wide com- 

 motion, was engulfed with development of fervid heat, within the molten sea. 



Only he who has a sure grasp on the controls can safely essay a 

 flight of the imagination where the conditions so surpass all ex- 

 perience. Barren's earlier, intensely analytical work showed 

 little evidence of the power of philosophic speculation, the scientific 

 use of the imagination, which is nevertheless the parent of inves- 

 tigation, even as Chamberlin's thought is the father of Barrell's. 

 barrell would have fallen short of the full stature of the philosopher 

 if he had not developed beyond the engineer. Such passages as 

 those quoted above show that he had grown in imaginative power, 

 and, being severely controlled by the logical habit of thought of his 

 early engineering and scientific career, he would have used that 

 power judiciously, greatly to the advantage and advancement of 



