Very, very bad, with brief descents into being humorously bad. It opens with a landing on Jupiter in its temperate forests:
"I hope we may find some four-legged inhabitants," said Ayrault, thinking of their explosive magazine rifles. "If Jupiter is passing through its Jurassic or Mesozoic period, there must be any amount of some kind of game."
In the fraction of the book I pressed through, that's as lively as the dialogue gets, and the action is no stronger.
The good bit is the grandeur of the terraforming plans -- Terra-forming, in fact; our own planet requires improvement:
As long ago as 1890, Major-Gen. A. W. Drayson, of the British Army, showed, in a work entitled Untrodden Ground in Astronomy and Geology, that, as a result of the second rotation of the earth, the inclination of its axis was changing, it having been 23@ 28' 23" on January 1, 1750, 23@ 27' 55.3" on January 1, 1800, and 23@ 27' 30.9" on January 1, 1850; and by calculation one hundred and ten years ago showed that in 1900 (one hundred years ago) it would be 23@ 27' 08.8". This natural straightening is, of course, going on, and we are merely about to anticipate it. When this improvement was mooted, all agreed that the EXTREMES of heat and cold could well be spared. 'Balance those of summer against those of winter by partially straightening the axis; reduce the inclination from twenty-three degrees, thirty minutes, to about fifteen degrees, but let us stop there,' many said. Before we had gone far, however, we found it would be best to make the work complete. This will reclaim and make productive the vast areas of Siberia and the northern part of this continent, and will do much for the antarctic regions; but there will still be change in temperature; a wind blowing towards the equator will always be colder than one blowing from it, while the slight eccentricity of the orbit will supply enough change to awaken recollections of seasons in our eternal spring.
"The way to accomplish this is to increase the weight of the pole leaving the sun, by increasing the amount of material there for the sun to attract, and to lighten the pole approaching or turning towards the sun, by removing some heavy substance from it, and putting it preferably at the opposite pole. This shifting of ballast is most easily accomplished, as you will readily perceive, by confining and removing water, which is easily moved and has a considerable weight. How we purpose to apply these aqueous brakes to check the wabbling of the earth, by means of the attraction of the sun, you will now see.
"From Commander Fillmore, of the Arctic Shade and the Committee on Bulkheads and Dams, I have just received the following by cable telephone: 'The Arctic Ocean is now in condition to be pumped out in summer and to have its average depth increased one hundred feet by the dams in winter. We have already fifty million square yards of windmill turbine surface in position and ready to move. The cables bringing us currents from the dynamos at Niagara Falls are connected with our motors, and those from the tidal dynamos at the Bay of Fundy will be in contact when this reaches you, at which moment the pumps will begin. In several of the landlocked gulfs and bays our system of confining is so complete, that the surface of the water can be raised two hundred feet above sea- level. The polar bears will soon have to use artificial ice. Perhaps the cheers now ringing without may reach you over the telephone.'"
There is so much exposition that two of the chapters are:
IV.-PROF. CORTLANDT'S HISTORICAL SKETCH OF THE WORLD IN A.D. 2000
V.-DR. CORTLANDT'S HISTORY CONTINUED
Bits of the 'history' are mildly interesting for their take on redesigning urban transit, but not very.
Eventually they meet a ghost Bishop on Saturn, who lectures them on physics and morality. This is toas the hunting on Jupiter is to .