18 THE NEW KNOWLEDGE. 



O=16. 0=16. 



Strontium .. .. Sr 87.6 Titanium . . .. Ti 48.1 



SULPHUR .. .. S 32.06 TUNGSTEN.. .. W 184.0 



Tantalum .. .. Ta 183 Uranium .. .. U 238.5 



Tellurium .. .. Te 127.6 Vanadium .. .. V 51.2 



Terbium Tb 160 Xenon Xe 128 



Thallium Tl 204.1 YTTERBIUM .. Yb 173.0 



Thorium., .. .. Th 232.5 YTTRIUM .. .. Yt 89.0 



Thulium.. '.. .. Tm 171 Zinc Zn 65.4 



TIN Sn 119.0 Zirconium Zr 90.6 



These are the bricks of the universe, out of the permuta- 

 tions and combinations of which all that exists is. Among 

 them you will find many long-known friends, such as cop- 

 per, iron, sulphur, silver, and, let us hope, gold. But 

 though many of them bulk large in the world's mass, others 

 lie furtively in the hidden places of the earth, and are ob- 

 tained and isolated only with infinite trouble and cost. 

 Thus, indium is four times, thorium nine times, caesium 

 fifteen times, and very impure radium thousands of times 

 rarer than gold; others are so rare that they cannot be 

 bought at all, and only by one's own painstaking labor 

 can they be brought to the light of day; such are kryp- 

 ton, praesodymium, samarium. Still others are both com- 

 mon and rare. For example^the silver-colored calcium is 

 literally common as dirt; it lies on every street. Seventy- 

 one per cent of every barrel of lime is calcium, and yet 

 calcium is worth fourteen dollars a thimble-full. The high 

 cost of the element is due to the difficulty of extraction * 



Now, what are these sphinxes ? Are these atoms sim- 

 ple, independently created, undecomposable little exist- 

 ences; or will they tell a story of evolution from simpler 

 existences in common with the rest of creation? What- 

 ever story there is, they alone can tell it. 



* Since this was written the price of calcium has sunk to about a dollar 

 a pound, owing to a new process of extraction. 



