20S 



The lecturei- liad never visited the locality ot" the baiite shaft, and 

 could not say why it had been abandoned. He did not agree with 

 Prof. Ijewis ia thinking that caxoclasite contained phosphoric acid. 



Mr. Lawson had not caught the lecturer's idea respecting the 

 rounding of the angles of pyroxene and a{»atite crystals. He corn- 

 batted the theory of iafneous action and favored that of solution 

 Mr. Lawion considered the objections to the igneous theory satifactory, 

 and did not think the lecturer had made out his case against the 

 theory of solution, which appeared to be, that, as rounded crystals of 

 pyroxene were found with similarly rounded crystals of apatite, the 

 niodihcation in each being evidently due to the same cause, and as 

 pyroxene was totally insoluble, the rounding could not have been 

 effected by a solvent. Mr. Lawson thought that water at very high 

 temperatures could dissolve almost anything. 



Mr. W. P. Andkrsox understood that the mica of this locality 

 was phlogo|)ite, which contained a small quanticy of water, and was in 

 consequence less refractory than muscovite, the chief commercial variety. 

 He had been informed that muscovite was found in the Mattawa district, 

 and wished to know if such were the case. The lecturer had no doubt 

 of it, as he had specimens probaljly referable to that variety. 



Jn reply to Mr. Small, the lecturer stated that his apatite statistics 

 were derived from the export returns, and consequently were exclusive 

 of the quantity mined and awaiting shipment, as well as of the 800 

 tons used in the Brockville Chemical Works. 



Mr. Laavsox asked what the New York lire tost for mica was? 

 Mr. Willimott was not certain, but thought it was merely resistance to 

 fi blow-pipe flime. It was recognized as the standard of value in 

 Canada. IMuscovite was untouched by the blow pipe tlime. 



In a discussion on apatite it was elicited that nothing less than 

 70% material ])aid, although arrangements wera reported as being in 

 progress foi- shipping 65% stuff to England for treatment by a new 

 process. Members of the British Association had informed Prof. 

 Macoun that the lefuse of the Tompleton mines was su])8rior to any- 

 thing woi-kedin England, and that in the future middlings would be of 

 great value. 



INIr. La»vson' stilted th;it untreated apitite was proving in the long 

 -run superior to superjihosphate. 



