This image shows a dramatic closeup of the east side of Horseshoe Falls, the Canadian section of the Niagara Falls complex.
There is no description on the back of this card, only the caption printed on the front.
Of note, on the left side of the falls, there appears to be a ledge that the falling water strikes before reaching the rocks at the bottom. This ledge is in fact the previous precipice, now eroded away and slowly being destroyed by the action of the falling water. The falls continuously retreat as a a result of this process, and have moved many miles upstream over the eons.
This card was used, and is dated 1951, but the image likely dates from the 1940s. The dark spot in the center right of the image is an ink stain.