The buildings on the left are bathhouses, not private homes. They were built by the springs, which catered to a steady stream of customers and tourists (a reason for those wide sidewalks, still there today, which invite strolling and looking about). Those in the photo were replaced in the early years of the 20th century, as the first commentator observed, referring to Buckstaff Bathhouse.
Also note that there are in fact 47 springs, which spew some 1 million gallons of 143-degree water every day. The springs are in Hot Springs National Park (and even before getting national park status, the area was a national reserve--the first such national "park," being acquired in 1832).

Fancy spas or bathouses are all along the left side of the street. The wide sidewalks are for the numerous wheelchairs used by the stove-up patrons who flocked to Hot Springs for the healing waters.

If I remember correctly, there were several springs, each with different mineral properties, so one might soak in one in the morning and another in the afternoon.

Obviously taken in winter, due to the bare trees and the steaming water. Oh, and nice touch with the St. Nicholas Hotel there too. Just in time for Christmas!

I visited Hot Springs for the first time in 1968. I made the mistake of taking water out of the wrong tap. As a northerner and a Caucasian, I and did not notice the "colored only" sign. A passerby angrily noted my mistake. I returned in the late eighties and found it a much friendlier place and the signs missing.

That's it! The actual hot spring itself! Of course, the cold spring is on the other side of the street.

Hot Springs is 45 miles west of my house. You can still get thermal baths at the Buckstaff Bathhouse, which has been operating since 1912. However, the town was known for its thermal springs and baths since the early 1800s. Now it is more popular for lakes, racetrack and theme park.