How far these conglomerates were pushed Ch.8, one cannot tell and therefore the barriers must lay farther southeastward. All through the St. Lawrence Valley from Belle Isle Strait to Vermont there must have been Lower Cambrian limestones and all of it was covered certainly from the north shore by the time of the Ordovician. This is seen at Montmorency where there is no L.C. under the Trenton. At Niagara there is also no L.C. even under the Redonda Tom - Chazy. It is possible known that some L.C. could be found beneath the present area of the Billy - Law rocks. L.Camb. sea Billy sea Thrust Conglomerates are quartzites.