l x ii PROCEEDINGS. 



WATSON L. BISHOP, ESQ., read a paper on " The Star-nosed Mole,"" 

 and exhibited specimens of the young. (See Transactions, p. 348.) 



PROF. J. G. MACGREGOR, D. So., communicated a paper " On thu- 

 use of the Wheatstone Bridge with Alternating Currents." 



SIXTH ORDINARY MEETING. 

 City Council Chamber, Halifax, 5th April, 1901. 



The PRESIDENT in the chair. 



A communication was read from the ENGINEERS' SOCIETY OF WESTERN 

 YoaK, Buffalo, offering the use of the society's rooms to any mem- 

 ber of the Institute who may visit the Pan-American Exposition. The 

 SECRETARY was directed to make a suitable reply. 



The following paper was communicated : 



THE RARE EARTHS: THEIR SCIENTIFIC IMPORTANCE AS REGARDS THB 

 PERIODIC LAW. BY W. H. MAGEE, PH. D , High School, Parrs- 

 boro, N. S. 



AT a meeting of scientists, it is, of course, unnecessary for me to- 

 apologize for the fact that the subject of my paper is one in which the 

 general public takes no interest. There are few, even among chemists,, 

 who take more th in a passing interest in the so-called Rare Earths. You, 

 however, who are seekers after truth, are aware that even in what might 

 seem the most despicable of materials there are startling discoveries await- 

 ing the patient investigator who will delve into the hidden mysteries 

 and bring to light truth, not only of rare interest to the scientific circle 

 whose sympathies he enjoys, but uf advantage to the general public which, 

 though impatient of the labor and details, is ever ready to avail itself of,, 

 and to liberally reward, results. 



The term R ire E irths, is, if not a misnomer, at least misleading, 

 since there are earths or oxides not classed in the group which are as rare,, 

 if not rarer, than these themselves. The usually accepted definition of 

 a rare earth is " a substance precipitable by oxalic acid from a weakly 

 acid solution and having the formula R 2 3 in which R stands for the 

 element of the oxide." This definition, however, if rigidly adhered to, 

 excludes Ce., Th. and Zr., which are usually ranked with the rare earths 

 and, being applied ever so generally, would place Tl., Gi., Ge., In., etc.,. 

 among the ordinary or at least not rare earths. 



