54 Mr. William Croohes [Feb. 18, 



thulium, and ytterbium, are out of place, and require to have their 

 atomic weights redetermined. 



— — — — — — — — All — Hg Bi Tl Pb 



The more I ponder over the arrangement of this zigzag curve, the 

 more I become convinced that he who fully grasps its meaning holds 

 the key to unlock some of the deepest mysteries of creation. As 

 Mr. Browning puts it in his ' Parleyings ' — " 'Tis Man's to explore 

 Up and down, inch by inch, with the taper his reason." Let us batter 

 at the door of the Unknown and do our utmost to get a glimpse of 

 some few of the secrets so darkly hidden. 



Let us return in imagination to pre-geological ages, before the 

 sun himself had been aggregated from the original protyle. We 

 require two very reasonable postulates ; let there be granted an 

 antecedent form of energy having jDcriodic cycles of ebb and swell, 

 rest and activity. Let there also be granted an internal action akin 

 to cooling operating slow^ly in the protyle. The first-born element 

 would, in its simplicity, be most nearly allied to protyle. This is 

 hydrogen, of all known bodies the simplest in structure and of the 

 lowest atomic w^eight. For some time hydrogen would be the only 

 existing form of matter (in our sense of the term). Between 

 hydrogen and the next formed element there would be a gap in 

 time, and in the interval the element standing next in order of 

 simplicity would gradually be approaching its birth-point. In this 

 interval we may sujipose that the evolutionary process soon to deter- 

 mine the birth of a new element would fix likewise its atomic weight, 

 its affinities, and its chemical position. 



In this genesis of the elements the longer the time taken up in 

 the cooling-down process, during which the hardening of protyle into 

 atoms takes place, the more sharj)ly defined would be the resulting 

 elements ; whilst the more raj^id and the more irregular the cooling, 

 the more closely the resulting bodies w^ould fade into each other by 

 almost imperceptible degrees. Thus we may conceive that the 

 succession of events which gave rise to such groups as platinum, 

 osmium, and iridium, — palladium, ruthenium, and rhodium, — iron, 

 nickel, and cobalt, — might have produced only one element in each 

 of these three groups if the process had been greatly prolonged. 

 And conversely, had the rate of cooling been much more rapid, 

 elements might have originated still more nearly identical than are 



