This building, pictured in an undated photo postcard, is Baker Memorial Chapel. The Chapel was a non-denominational church for patients at Trudeau Sanatorium. The building was designed by J. Lawrence Aspinwall, who designed the Saranac Laboratory and the Trudeau Building at 118 Main Street, and William L. Coulter, architect of many Cure Cottages and Great Camps in the area.
To learn more about Baker Memorial Chapel, visit our wiki.
And to learn more about the possible sale of the Sanatorium/AMA Campus, check out this article in the Adirondack Daily Enterprise.