The standard color scheme used in these phenomenoscopes depicted carbon 
atoms in green, sulfur in yellow, oxygen in
red, and hydrogen in blue. Cotton's assembly, as seen from a distance, was 
generally turquoise because it consisted mostly of carbon and hydrogen, and 
because Hackworth's point of view was so far away that the thousands of 
individual atoms all blended together. It was a gridwork of long, straight, but 
rather bumpy rods laid across each other at right angles. Hackworth recognized 
it as a rod logic system—a mechanical computer.