NOVEMBEE 4, 1898.] 



SCIENCE. 



609 



fellows and increasing its intensity and de- 

 tail. 



As I have said, my researches are far 

 from cornplete, but about one of the bodies 

 I may speak definitely. High up in the 

 ultra-violet, like a faint nebula in the dis- 

 tant heavens, a group of lines was detected, 

 at first feeble and only remarkable on ac- 

 count of their isolation. On further purifi- 

 cation these lines grew stronger. Their 

 great refrangibility cut them off from other 

 groups. Special processes were employed 

 to isolate the earth, and u^sing these lines as 

 a test, and appealing at every step to the 

 spectrograph, it was pleasant to see how 

 each week the group stood out stronger and 

 stronger, while the other lines of yttrium, 

 samarium, ytterbium, etc., became fainter, 

 and, at last, practically vanishing, left the 

 sought-for group strong and solitary. Fin- 

 allj', within the last few weeks, hopefulness 

 has emerged into certainty, and I have ab- 

 solute evidence that another member of the 

 rare earth groups has been added to the 

 list.- Simultaneously with the chemical and 

 spectrographic attack, atomic-weight de- 

 minations were constantly performed. 



As the group of lines which betrayed its 

 existence stand alone, almost at the ex- 

 treme end of the ultra-violet spectrum, I 

 propose to name the newest of the elements 

 -Monium, from the Greek /j'^vo?, alone. Al- 

 though caught by the searching rays of the 

 spectrum, monium oifers a direct contrast 

 to the recently discovered gaseous elements, 

 by having a strongly- marked individuality; 

 but, although so young and willful, it is 

 willing to enter into any number of chemical 

 alliances. 



Until my material is ia a greater state of 

 purity I hesitate to commit myself to fig- 

 ures, but I may say that the wave-lengths 

 of the principal lines are 3120 and 3117. 

 Other fainter lines are at 3219, 3064 and 

 3060. The atomic weight of the element, 

 based on the assumption of R2O3, is not far 



from 118 — greater than that accepted for 

 yttrium and less than that for lanthanum. 



I ought almost to apologize for adding to 

 the already too long list of elements of the 

 rare earth class — the asteroids of the terres- 

 trial family. But as the host of celestial 

 asteroids, unimportant individually, become 

 of high interest when once the idea is 

 grasped that they may be incompletely 

 coagulated remains of the original nebula, 

 so do these elusive and insignificant rare 

 elements rise to supreme importance when 

 we regard them in the light of component 

 parts of a dominant element, frozen in em- 

 bryo, and arrested in the act of coalescing 

 from the original protyle into one of the 

 ordinary and law-abiding family for whom 

 Newlands and Mendeleeff have prepared 

 pigeon-holes. The new element has another 

 claim to notice. ISTot only is it new in it- 

 self, but to discover it a new tool had to be 

 forged for spectroscopic research. 



Further details I will reserve for that 

 tribunal before whom every aspirant for a 

 place in the elemental hierarchy has to 

 substantiate his claim. 



These, then, are some of the subjects, 

 weight}' and far-reaching, on which my own 

 attention has been chiefly concentrated. 

 Upon one other interest I have not yet 

 touched — to me the weigtiest and the far- 

 thest reaching of all. 



No incident in my scientific career is 

 more widely known than the part I took 

 many years ago in certain psychic researches. 

 Thirty years have passed since I published 

 an account of experiments tending to show 

 that outside our scientific knowledge there 

 exists a Force exercised by intelligence dif- 

 fering from the ordinary intelligence com- 

 mon to mortals. This fact in my life is, of 

 course, well understood by those who hon- 

 ored me with the invitation to become your 

 President. Perhaps among my audience 

 some may feel curious as to whether I shall 

 speak out or be silent. I elect to speak, 



