130 
THE GEOLOGIST. 
Mr. Strickland supposes that currents of water (or possibly of 
wind, operating during ebb tide) flowing in a certain direction 
may have disposed the sand in ridges parallel to that direction, 
and the carbonate of lime may have afterwards been attracted 
into these ridges in preference to the intermediate portions. 
This view is confirmed by the fact that these concretions have 
frequently a pebble attached to the larger end, as though it had 
protected a portion of sand from the current, and caused it to 
accumulate in a ridge on the lee side, a circumstance which may 
frequently be observed when sand is drifted by the wind or 
water. 
Dec. \4<th. — Mr. Murchison, President, in the chair. 
1. On the Ridges, Elevated Beaches, Inland Cliifs, and 
Boulder Formations of the Canadian Lakes and Valley of St. 
Lawrence." By Mr. Lyell, F.G.S. Mr. Lyell^s paper was con- 
cluded on the 4th of J anuary. 
After adverting to his former paper, On the Recession of the 
Falls of Niagara," and the observations which he made jointly with 
Mr. Hall, in the autumn of 184*1, Mr. Lyell gives an account of 
additional investigations made by him in June, 1842, in the 
course of which he found a fluviatile deposit, similar to that of 
Goat Island, on the right bank of the Niagara, nearly four miles 
lower down than the great falls. The fresh-water strata of sand 
and gravel here alluded to occur at the Whirlpool ; they are ho- 
rizontal, about forty feet thick, plentifully charged with shells 
of recent species, and are placed on the verge of the precipice 
overhanging the river; they are bounded on their inland side 
by a steep bank of boulder clay, which runs parallel to the 
course of the Niagara, marking the limit of the original channel 
of the river before the excavation of the great ravine. Another 
patch of sand, with fresh-water shells, was found on the oppo- 
site or western side of the river, where the Muddy Rmi flows in, 
about half a mile above the A^Tiirlpool. From this position of 
strata, it is inferred thst the ancient bed of the river, somewhere 
