Like many Americans, I have recently been diagnosed with a vitamin D deficiency. In addition to drinking milk, eating dark leafy greens, and taking 2000 IU’s of D a day, I’ve also been trying to get as much sunlight as possible. When I came across this article in the November 7, 1903 Scientific American, I realized that a possible reason for my deficiency is my home’s inability to rotate.
Pictured here is a home that turns with the sun, which was on display at the Exposition de l'Habitation in Paris in 1903. The idea behind the revolving home, created by Dr. Pellegrin and Parisian architect M. Pettit, was that if home could rotate with the sun, it would be provided with the sunlight needed to create a more healthful and sanitary home. The design of the home was meant to fulfill requirements of heliotherapy based on work by Dr. Nils Finsen, the 1903 Nobel Prize winner in Physiology or Medicine.
The house was built upon a turntable flush to the ground. The basement (which was built free from the home and did not rotate) served to house the machinery used to turn a vertical shaft that rotated the house. “The ball bearings, on which the turntable rests, have a receiver of considerable diameter, and arranged on a suitable metallic crown supported by a massive annular masonry wall within which a staircase is built, fixed to the turning structure and carrying roller at its lower end which rest on the floor of the basement and enable the staircase to move with the house…The rotation is obtained by means of a pinion which is geared to a circular set of teeth fixed on the platform.”
The house could be turned by hand which required a lever to be moved once an hour, or by motor which necessitated the house to make a full revolution in 24 hours.
Over the years, we have continued to follow the sun in order to reap its energy. Today, scientists and engineers are using mechanized solar trackers to harvest the sun's heat to make electricity. Mirrors and lenses move with the sun and are then used to concentrate sunshine onto a receiver. However, I would avoid using concentrated solar thermal power to help treat a vitamin D deficiency, as it creates temperatures that can go above 600 degrees Celsius.