In that book by George Leonard titled Somebody Else Is on The Moon, comes in handy in the case of interpreting the canals on Mars. They haven't been reported by anyone in a long time, nobody makes a comment or anything. Why?
Well, digital cameras were reporting them a while back, so I imagine that ALL OF THOSE CANALS did not just disappear.
What George Leonard reported is that he saw a photograph that someone he knew who was connected with the space effort. It was a a narrow mountain pass, something like that, and he said that the picture was kind of sidelong, taken from a horizontal angle. Are you all familiar with those stadiums that we have that have something like giant tarpaulins that cover stadiums to protect from the cold and the rain? He said that there was a narrow mountain pass that was covered by something flat, and there he could see a straight column underneath it. The crater Linné on the Moon was seen during a certain long period of observation to be wide open, then partially covered, covered and disappeared, and then partially uncovered.
I think that the Martians covered over all of their canals.