A little ramble through 19th century astronomy - oval shadows on Jupiter in 1874

 Academy Newspaper Saturday 16^th May 1874 

Mr. Brett, the well-known artist, has, from a consideration of the shadows. cast by certain oval-shaped white markings on Jupiter, given reason to conclude that we do not see the true body of the planet, but only a semi-transparent stratum of vapour or liquid. In connexion with  this idea, we must remember that Jupiter is, on  the whole, very little more dense than water, so that  there seems a strong  probability that a  considerable portion of its visible diameter is  composed of vapour.

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