NO. 2 METHOD OF REACHING EXTREME ALTITUDES 57 



If we consider the final mass of the last " secondary " rocket 

 plus the mass of the flash powder and its container, to be four times 

 the mass of the flash powder alone, we should have, for the ^nal 

 mass of the rocket, four times the above masses. These final masses 

 correspond to the " one pound final mass " which has been mentioned 

 throughout the calculations. 



The " total initial masses," or the masses necessary for the start 

 at the earth, are at once obtained from the data given in table VII. 

 Thus if the start is made from sea-level, and the " effective velocity 

 of ejection " is 7,000 ft./sec, we need 602 lbs. for every pound that 

 is to be sent to " infinity." ^ 



We arrive, then, at the conclusion that the " total initial masses " 

 necessary would be 



6,436 lbs. or 3.21 tons ; flash just visible, and 

 33,278 lbs. or 16.63 tons (or less) ; flash strikingly visible. 

 A " total initial mass " of 8 or 10 tons would, without doubt, raise 

 sufficient flash powder for clear visibility.''^ 



These masses could, of course, be much reduced by the employ- 

 ment of a larger telescope. For example, with an aperture of two 

 feet, the masses would be reduced to one-fourth of those just given. 

 The use of such a large telescope would, however, limit considerably 

 the possible number of observers. In all cases, the magnification 

 should be so low that the entire lunar disk is in the field of the 

 telescope. 



It should be added that the probability of collision of a small 

 object with meteors of the visible type is negligible, as is indicated in 

 Appendix G, page 64. 



This plan of sending a mass of flash powder to the surface of the 

 moon, although a matter of much general interest, is not of obvious 

 scientific importance. There are, however, developments of the 

 general method under discussion, zvhich involve a number of im- 

 portant features not herein mentioned, which could lead to results of 

 much scientific interest. These developments involve many experi- 

 mental difficulties, to be sure ; but they depend upon nothing that is 

 really impossible. 



^ A simple calculation ^° will show that the total initial mass required to 

 send one pound to the surface of the moon is but slightly less than that 

 required to send the mass to " infinity." 



