The Eight Volumes

Yes, I think that these proposed eight volumes would adequately present James Blish's interconnected works:

I, Some Early Blish.
II, The Galactic Cluster Trilogy.
III, Jack Loftus.
IV, After Such Knowledge.
V, The Seedling Stars.
VI, Cities In Flight.
VII, The Quincunx Tetralogy.
VIII, The Haertel Scholium Coda.

The Haertel Scholium, ie, works referring either to the character Adolph Haertel or to his interstellar drive, comprises Volumes II, III, VII and VIII and a third of IV. Anyone who had read to the end of Vol VI would by then have encountered three Haertel overdrive futures and one spindizzy-Dirac communicator future. (The spindizzy or Dillon-Wagonner gravitron polarity generator is, like the Haertel overdrive, a faster than light interstellar drive.) Vol VII presents a Haertel overdrive-Dirac communicator future.

The instantaneous Dirac communicator, simultaneously receiving all past, present and future Dirac messages in a single "beep" of sound and light, first appeared in a one-off story never published in its original form because, under the guidance of Blish's Editor, John W Campbell, it was transformed into the concluding episode of a four part "Okies" series collected as Earthman, Come Home. That volume plus one pre-Okie novel, one juvenile Okie novel and one post-Okie novel equals Cities In Flight.

The pre-Okie novel, They Shall Have Stars, is a joint novelisation with new material of two stories each showing one of the two discoveries, anti-agathics and antigravity, that were necessary for Okie civilization. Logically, there should be a third story showing the invention of the Dirac communicator. In fact, that story exists but could not be incorporated into Cities In Flight because Blish wanted his Okie characters to meet challenges without being helped by messages from their future. Therefore, both the invention of the Dirac and the extraction of messages from the beep are described in the independent story, "Beep," novelized as The Quincunx Of Time.

In the longer version, one Dirac message describes the background of Blish's story, "A Style In Treason," and another is transmitted in his novel, Midsummer Century. Thus, Volume VII, for which I suggest the title The Quincunx Tetralogy, would contain:

Welcome To Mars, about Haertel's discovery of antigravity;
The Quincunx Of Time;
"A Style In Treason";
Midsummer Century.

The early Adapted Men stories could have fitted into the Okie sequence, and indeed looked as if they were going to, but then the two series developed in different directions so the former are collected as The Seedling Stars. Thus, the contents of Volumes V, VI and VII grew from two roots, the earliest written Okie and "pantropy" (science of Adaptation) stories, but also incorporated other material from the Haertel Scholium (Welcome To Mars and The Quincunx Of Time) and via the Dirac transmitter ("A Style In Treason" and Midsummer Century).

Because most of these works describe the consequences of future scientific discoveries, it makes sense that, in the first part of After Such Knowledge (ASK), Blish presents a fictitious biography of Roger Bacon, the discoverer of scientific method. Because Bacon, a scientist, was mistaken for a magician, it is also appropriate that the second part of ASK is neither sf nor about scientists but fantasy about magicians. The third part of ASK is a Haertel overdrive novel about a future conflict between theology and science.

"Common Time," the opening story of Galactic Cluster, presents Haertel as an elderly scientist receiving a report back from the pilot of the first successful test flight with his overdrive whereas Welcome To Mars, written later, presents him as a teenager discovering antigravity and flying to Mars while a slight variation on that version of Mars is presented in the story that would introduce Vol VIII. These works present creativity without linearity.