372 Clarke and Catlett — Nickel Ore from Canada. 



Besides the testimony of marine fossils, one further obser- 

 vation contributes greatly to our knowledge of the relation of 

 land and sea on the south side of Massachusetts bay while this 

 area was enveloped by the continential glacier. On the shore 

 of a peninsula in Cohasset Little Harbor, fifteen miles south- 

 east of Boston, pot-holes similar to those of water-falls on 

 rivers are found in two localities, reaching from sea level to a 

 height of fifteen feet. The contour of their vicinity precludes 

 the possibility of referring their origin to any stream since the 

 close of the glacial period ; and they must doubtless be attrib- 

 uted to the action of a water-fall plunging down hundreds of 

 feet through a moulin of the ice sheet.* To Mr. Bouve, long 

 the president of this Society, belongs the honor of first observ- 

 ing these pot-holes and appreciating their significance. It was 

 under his guidanee that my visit to them was made ; and it is 

 with his permission that I speak of them here, previous to the 

 detailed description which he will later present before the 

 Society. Such water- wearing of the bed-rock could not take 

 place beneath the sea level, so that they prove that here during 

 a part, probably the later part, of the time when this area was 

 covered by the ice-sheet, the land stood at least as high as now, 

 not being depressed under its vast weight. 



Art. XXXIX.— A Platiniferous Nickel Ore from Canada ; 

 by F. ~W. Clarke and Charles Catlett. 



During the autumn of 1888 we received, through two dif- 

 ferent channels, samples of nickel ores taken from the mines 

 of the Canadian Copper Co. at Sudbury, Ont. From one 

 source we obtained two masses of sulphides, to be examined 

 for nickel and copper ; from the other source came similar sul- 

 phides, together with a series of soil and gravel-like material, 

 seven samples in all. In the latter case an examination for 

 platinum was requested, and in five of the samples it was 

 found, the gravel above mentioned yielding 74*85 oz. of met- 

 als of the platinum group to the ton of 2000 lbs. At the out- 

 set of the investigation we were decidedly incredulous as to the 

 existence of platinum in such ores ; but the discovery of sper- 

 rylite by Mr. Wells in material from the same mines gave our 

 work a wholesome stimulus, and the assays were carefully car- 

 ried through. 



The sulphide ores submitted to us from Sudbury were all of 

 similar character. They consisted of mixed masses, in which 

 a gray readily tarnishing substance was predominant, with 



* Compare Quart. Joum. Geol. Soc, vol. xxx, 1874, pp. 750-771. 



