132 PALMKR : 



But how energetic is the diatom ? Writers are not want- 

 ing who will have us believe that the crawling diatom gives 

 onl}' a feeble exhibition of power. They will remark that 

 "the mass of the diatom is small, and the rate of progress 

 slow." By implication, the force expended is almost negli- 

 gible. But is it ? The conclusion does not lie in the pre- 

 mises as stated. Let us, as heretofore in this discussion, try 

 to consider the facts with some approach toward precision. 



True it is that the diatom is small as compared with an 

 elephant or a man. True it is, also, that the diatom's rate of 

 progress is less, in miles per hour, than the normal rate of 

 progress in elephant or man. All this is obvious enough. 

 But since we are asked to appreciate these facts, let us do so. 

 Only let us really consider them, and follow them to their 

 logical consequences. 



First of all, let us try to picture to ourselves how very 

 small the diatom is as compared, for instance, with the human 

 body. For the length of the diatom we may well enough 

 take the microscopical measurement of 70 microns (/a). The 

 micron is 1/25,000 of an inch. For the man, let us select 

 an individual six feet high. This height is equivalent to 



72 inches y 2^,000 fi ~- 1,800,000 /u.. 



The ratio for length then becomes 



70 : 1,800,000 :: I : 25,714. 



The man is, in fact, 25,714 times longer tlian the diatom. 



We have seen * that a lively diatom traveled at the rate 

 of nearly two inches per hour. This is a certain number of 

 times its own length. But suppose this diatom to be increased 

 to the length of the man, and still to retain its ability to 

 travel as many of its own lengths as ever in an hour. Kvi- 

 dently this monstrous diatom, increased 25.714 times the ori- 

 ginal length, will trav^el, not two inches, but 



2 X 25,714 -- 51,428 inches per hour. 

 ■""Some ()l)serv,'ilions OH Diiitom Motion," Vol. II, No. 4, July, 1907. 



