Though it is commonly admitted by geologists, that both land-ice and floating ice are capable of striating rocks, when armed with erratics; careful discriminations seem to be largely neglected. The question, whether river-ice was ever the active agent in scratching rocks, had been raised in the writer's mind several years since by a few observations in Dakota. Diligent search at several seemingly favorable localities had given only negative evidence, until this past season, when two or three observations seem to demonstrate the fact that such is not very infrequently the case.
Proceedings of the Iowa Academy of Sciences
©1890 Iowa Academy of Science, Inc.
Todd, J. E.
"Striation of Rocks by River Ice,"
Proceedings of the Iowa Academy of Science, 1(Pt. 2), 19-20.
Available at: https://scholarworks.uni.edu/pias/vol1/iss2/8