Every age has the Stonehenge it deserves-or desires. I lectured on this subject long ago. It always provoked cries of delight from a general audience when I contrasted pictures of the wildly jagged stones seen by romantic eyes with others showing the smooth stones and regular form of the Roman temple of the Tuscan order apparent to the classical vision. I ended my lecture with Stonehenge as it appeared to our scientific age-but I did not at that time dream that our greatest prehistoric monument would actually be taken over by astronomers and recognized as a celestial observatory and calculating machine.