Welded ship hulls started in 1917 or so, so this is way too early. Possibilities are flush rivets with countersinking and simply an optical illusion; the thickness of the plates exceeds the protrusion of the rivets enough that you don't see it. You can see this with many pictures of ships where a close up would clearly show rivets.

Whaleback \Whale"back`\, n. (Naut.)
A form of vessel, often with steam power, having sharp ends
and a very convex upper deck, much used on the Great Lakes,
esp. for carrying grain. Source: Free Dictionary

whaleback (ˈweɪlˌbæk)
— n
1. something shaped like the back of a whale
2. a steamboat having a curved upper dec Source: Dictionary.com

The seams look welded. 1893 seems early for the process on such a large scale. Any info?

It appears that the little girl dressed in her Sunday finest at the lower right is snapping a 'Kodak' of the whale.

The S. S. Meteor is on display in Superior, Wis.

This barge lasted over fifty years, from its delivery in 1893 to its scrapping in 1946. It was constructed by American Steel Barge in Superior, Wisconsin, when that company was under the ownership of the whalebacks' greatest friend, Alexander McDougall. When owned by Bessemer Steamship Corp. and then Pittsburgh Steamship Co., it was based in Duluth. This barge was part of a small fleet later sold to Great Lakes Engineering Works of Ecorse, Michigan. It was badly damaged in a collision in October 1905, between the Soo Locks and Lake Huron. Before it was moved in 1912 from the Great Lakes to the Atlantic coast for use in the New England coal trade, its length was shortened by 31 feet (from its original 292 feet). It was then renamed the Salem. Several decades and name changes later, its service came to an end in Houston.