One of the best "hard" science fiction writers in the field was James Blish (1921-1975), an award-winning author of over twenty books and several short stories. A one time biologist and former science writer, Blish gained long-sought public recognition via his Star Trek paperback adaptations during the late 60s, with the last volume published posthumously in 1976, as well as writing the very first paperback original novel (1970's Spock Must Die) based on the TV series (here's one fan's recollection of Blish's Trek books).
If memory serves, in one of his written introductions to the Trek books, Blish commented on how his previous and post "Star Trek" body of work had actually increased in sales due to the adaptations of the TV show. One of the beneficiaries of this renewed interest had to have been the 1970 collection of Blish's "Oakie" novels, Cities in Flight, an ambitious work combining technology, action adventure and some sly social comment.
Beginning with 1956's They Shall Have Stars, Blish gets the saga going with a tale set in the early 21st century (where the USSR is still in existance), in which a increasingly-totalitarian West, already allowing evangelicalism to distract the public from what's really going on (there's a chilling scene early on involving young children), develops the anti-gravity "spindizzy" drive, which can transport whole factories, and eventually cities, into space. The grim, downbeat tone of Stars, lightened somewhat by witty dialogue and pointed satire ("anti-agathic" drugs, which slow down aging and allow people to live for centuries and which play a part in the books, are developed by the "Pfitzner" corporation, a stand-in for Blish's former employer, Pfizer) is offset by the next (chronological) novel, 1962's A Life for the Stars, which reads like a Young Adult novel. In this installment, a teenager named Chris, some ten centuries after the events of the first novel, is taken against his will to the city of Scanton, PA, which, like many other cities on Earth, travels across space, bartering various services with other cities and planets along the galaxy to survive and becoming known as "Oakies", named after the transcient workers of the Great Depression. Chris has a number of adventures before winding up in the spindizzy-powered New York City, where Blish introduces the piviotal protagonist of his saga, NYC Mayor John Amalfi.
Amalfi is the main character (though Chris gets a brief, somewhat unfortunate, mention) in 1955's Earthman, Come Home, which, like the previous novel is episodic, but more adult in tone. Amalfi and his staff, including city manager Hazelton, try to keep NYC afloat (literally as well as figuratively) while dealing with rival Oakie cities, hostile civilizations ("clients") on other planets and corrupt law enforcers, as well as equally hostile conditions (like the "Rift") in outer space. In the process, Amalfi saves Earth from an alien invasion and, using the spindizzy drive, is able to settle NYC (while making a profit) onto a new Earthlike planet, which is propelled out of the Milky Way.
Almost as a bookend, the events of the last novel, 1959's The Triumph of Time, takes everything full circle, as a tired, aging Amalfi must cope with political and religious conflicts on the new planet while trying to prevent a collision between galaxies. Such a collision, due in part to use of the spindizzy, will result in the known universe contracting and possibly being destroyed. By the end of Triumph, everything that the characters (and the readers) know, is changed forever.
Cities in Flight (which you can reserve here) isn't perfect; it's tough to keep track of the continuity between the stories, and the episodic storytelling can get a little too leisurely. Characterzation, especially of the few females in the storyline, is, aside from the interestingly shaded Amalfi, hit and miss. But the explanations of the various scientific principals behind the technology depicted in the books is outstanding and never gets in the way of the plot. "Hardware" science fiction fans will appreciate the effort Blish put in.
(Another exciting and thought provoking work by Blish, A Case of Conscience, can be found in this collection carried by the library.)