F. D. Adams — Melilite-'bearing Rock. 269 



Aet. XXXIII. — On a Melilite-'bearing Rock {Alnoite) from 

 Ste. Anne de Bellevue near Montreal, Canada ; by Frank 

 D. Adams. 



At the extreme southwest corner of the Island of Montreal 

 and about twenty miles from the city of the same name, is the 

 village of Ste. Anne, sometimes called Ste. Anne de Bellevue 

 to distinguish it from a number of other places of the same 

 name in the Province of Quebec. Here both the Grand 

 Trunk and Canadian Pacific Railways cross the Ottawa river 

 on bridges but a few yards apart, while under these and 

 directly in front of the village is a short canal constructed to 

 avoid the rapids which impede navigation at this point. Ow- 

 ing to the difficulty of navigating the Ottawa below this canal 

 during times of very low water, it was decided to remove a 

 ridge of rock in the river bed opposite the lower end of the 

 village of Ste. Anne, and in this way to open up communica- 

 tion with a deeper channel on the opposite side of the river. 

 In the summer of 1877 accordingly the Dominion Government 

 put down cofferdams and having laid the bed of the river bare 

 at this point blasted out the obstruction. 



While this work was in progress, the locality was visited by 

 Dr. B. J. Harrington, at that time connected with the Geolog- 

 ical Survey of Canada, who found the bed of the river to be 

 composed of well bedded sandstones and conglomerates of 

 Potsdam age dipping to the south at an angle of 3^- to 4 de- 

 grees, cut through by a nearly vertical dike three feet thick 

 and running 1ST. 20° W. At one point a branch was observed 

 running off from the larger dike. Much of the rock was 

 entirely decomposed but a number of comparatively fresh 

 specimens were obtained and notes on the mode of occurrence 

 of the dike were published by Dr. Harrington in the Report 

 of the Geological Survey of Canada for 1877-78, page 89 G, 

 and also in the Canadian Naturalist, vol. ix, p. 253. 



The rock however was fine grained and for the most part 

 much decomposed, so that its true character was not recog- 

 nized until the discovery by Tornebohm in 1882 of a melilite- 

 bearing rock which he termed a melilite basalt* on the Island 

 of Alno in Sweden, which rock in hand specimens so closely 

 resembled that from Ste. Anne, that Prof. Rosenbusch of 

 Heidelberg to whom a specimen of the latter had been given 

 was led to carefully reexamine the sections of it for melilite. 

 One or two crystals of this mineral found in one of the sec- 



*A. E. Tornebohm: Melilitbasalt frtin Alno, Geol. Foren. i. Stockholm Forh., 

 1882, p. 240. 



