I read this book about 4-Jan-2007. I've read this book before. The book is copyright 1934. This note was last modified Monday, 19-May-2014 16:39:54 PDT.
This is book 3 of the "Skylark" series.
This note contains spoilers for the book.
Probably the series ender, given the dates.
For some reason I haven't been finding their extended foray into the fourth dimension very interesting; I skimmed that pretty lightly this time. I can't find anything objectively wrong with it, though. And it's what gets them so lost they need to build the Valeron to be able to find home again.
They also capture the "pure intellectuals" that turned up earlier, and put them into a time-stasis capsule. Also, a bit later, Duquesne; that also contributes to making it seem like a series-ender.
On the other hand, the Chlorans vs. Valeron is very much a setup for Skylark DuQuesne (#4). But there was a chlorine planet in the first book.
There's a nasty continuity problem; at one point Seaton tells the pure intellectuals that it's his physical form that let him survive rotation through the fourth dimension; that's why their previous rotational experiments hadn't worked. But his plan for the capsule is to rotate them at the end of the long-distance normal trip. Neither he nor they seem to view that as a death sentence. And, by the way, why bother with the long trip if you're going to do the fourth dimensional rotation anyway? (Other than that it's the trip that fails and lets them loose, of course.)