224 Proceedings of Learned Societies. 



rudders of vessels chased ; there is no ship afloat which has sufficient 

 strength to resist its power ; it is characterized by great economy, 

 simplicity, and safety in its working : and, in working it, neither the 

 battery itself nor the men can be exposed, the apparatus being much 

 below the line of flotation. 



Saturday, September 17th. — In the section of Geography, a 

 paper by Lord Milton and Dr. Chbadle attracted much atten- 

 tion. It described an expedition across the Rocky Mountains 

 into British Columbia, through the Yellow Head Pass. "With 

 regard to the possibility of making a railway by this route, it 

 is said to offer no engineering difficulties of any importance ; the 

 valley being in many places wide and unobstructed except 

 by timber, and the flooding of the river by the melted snows 

 not interfering with the passage of the valley. The reasons for pre- 

 ferring this route to any other yet opened are — 1st. That it lies far 

 removed from the boundary line, well within British territory ; 2nd. 

 That it passes entirely through a country inhabited only by peaceable 

 and friendly Indians ; and 3rd. That it offers the most direct com- 

 munication from Canada to the gold regions of British Columbia, 

 and from it the Sashwass and Okanagar districts, as well as the road 

 on the Frazer, are easily accessible. 



Mr. Bates' paper on The Delta op the Amazons stated that 

 the delta was of a vastness commensurate with the size of the river 

 itself. It forms a triangle, each side of which is about 180 miles, the 

 mouth of the river being thus 180 miles in width. Within this gulf, 

 the island of Marajo (as large as Sicily) divides the river into two 

 channels, the northern, or Marie Amazons, 40 miles wide, and studded 

 with islands, the southern, or Para River, clear in course, and about 

 35 miles in width. The Amazon delta is not, as might be supposed, 

 an unhealthy region of swamps. On the contrary, no part of it seems 

 to be wholly due to fluvial deposit. In large areas the soil is sandy, 

 with a rocky substratum ; and, in several places, calcareous beds are 

 found, containing an abundance of fossil marine shells. The country 

 is healthy, and the temperature, though very high and uniform, is not 

 so high as in many countries farther removed from the equator. The 

 mean temperature in three years' observation was 81° Fahr. Sin- 

 gularly enough, a district, commencing at the western end of Marajo, 

 and extending about 80 miles in length and breadth, presents all 

 the characteristics of a true delta — a district composed of mud and 

 sediment, intersected by deep channels. The conclusion arrived at 

 is, that the true delta of the river is confined to the district just 

 mentioned, now distant 140 miles from the sea, and that, at no very 

 distant period, the seaward portion constituted a series of islands 

 lying off the mouth of the river. This conclusion is borne out by 

 observations made by Mr. Bates on the former of the two districts. 



