Images are from my personal historical photos collection
Whaleback ships were a unique design that was adopted to ship ore across the Great Lakes and particularly Lake Superior. Their shape was designed to lessen the impact of turbulent surf. When fully loaded they looked more like a submarine than a surface ship. They were used mostly as a tow barge, schooners had mostly been used before this.
Whalebacks were fairly common throughout the early 20th century. 44 of them were built between 1887 and 1898. Most of them were built in Duluth, MN or Superior, WI as freighters for the iron range. None of them are left except one that is a museum ship in Superior, WI, the SS Meteor. (here is a link to the Whaleback Museum: https://superiorpublicmuseums.org/ss-meteor/)
When loaded whalebacks were hard to see and were often run into by ships that couldn’t see them. Their hatches tended to leak and bend during stress which made them a hazard. The Whaleback is the forefather to the modern ore freighter that we commonly see now, like the neanderthal to the modern man.