JF Ptak Science Books Quick Pos
Maybe you don't see it, but the first thing I thought of when I saw this small (and here enlarged) ad in The Engineer for 1869 was its remarkable-ish similarity to hieroglyphs. The point is fairly strong, and a person can get a very good idea of how things were being built in 1869--especially if you were an alien and had deciphered what the purpose of all these things was. Granted it isn't as simple or complex as the SETI plaque on the Pioneer 10 and 11, but it does have the flavor of a message to the future, or to another life form in another place.
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