It's not constructed of stone at all, but of nearly 9 million pounds of cast iron. The exterior has to be repainted occasionally. That last occurred in 2010 when more than 500 gallons of paint was applied. A more comprehensive phased restoration project was initiated in 2012 that involves removal of all paint from the dome, repairing defects in the ironwork, resealing, and finally repainting with an epoxy and urethane paint system. The skirt portion of the dome has been completed. Remaining work, including restoration of the interior face, is awaiting approval of funds.

The dome and even the main buildings don't look as white as they are today. I always thought it was the natural color of the stone that made it white. Did they start white-washing it later?

... with automatic fertilizer and spreader!

Whenever I see large fields of manicured grass in these old photos I wonder how were these fields were kept mowed before the era of modern mowing tractors? Anybody know?

[Horse-drawn mowers, such as this from around the same time. -tterrace]

Hey that's pretty clever- they mow and fertilize at the same time! ;-)