Recently, I posted about "Time Patrol Collections" but neglected to mention that The Guardians Of Time (New York, 1981) also includes "Of Time And The Rover," an Afterword by Sandra Miesel, although I had mentioned this Afterword here and here.
Miesel starts by observing that Anderson had roved past, future and alternative time for over three decades. We must now say for over five decades.
She uses the phrases, "Translation in time..." (p. 245) and "...time transit..." (p. 246), convenient labels for different treatments of time in fantasy and sf, e.g., she mentions, among other examples:
"The Man Who Came Early" (time travel);
Three Hearts And Three Lions (travel between timelines);
Tau Zero (space travel but with time dilation).
These three works are respectively historical sf, heroic fantasy and hard sf.
Miesel argues that:
temporal transitions challenge fictional characters;
"...response to challenge is Anderson's quintessential theme..." (p. 245);
both space travel and time travel "...offer the extension of mastery through knowledge and the enlargement of being through experience..." (ibid.);
also, Anderson saw "...the supreme knowledge [as] that gained through experience." (ibid.);
whereas archaic societies ignore or deny history, modern civilization searches for roots and speculates about growth;
Anderson's historically based fiction addresses this need.
I try to paraphrase but sometimes Miesel's succinct prose is already a summary. I merely summarize because I do not disagree. For discussion of James Blish on his quintessential theme of "knowledge," see here.
In one paragraph on p. 248, Miesel compares Anderson's Time Patrol series with five time travel works and with two parallel timeline novels. Of the five time travel works, I value only Ward Moore's Bring The Jubilee. For discussion of inconsistencies in some time travel fiction, see here. A better comparison for the "Two characters [who] escape to the more congenial nineteenth century..." would have been with Jack Finney's nostalgic time travel fiction.
The parallel timeline novels are mentioned in order to compare Anderson's Time Patrol with Piper's Para-Time Police and Norton's Crosstime Service. However, the Patrol polices pastwards and futurewards travel along a single mutable timeline whereas the other two organizations police present-moment sideways travel between many parallel timelines. Norton's title, The Crossroads Of Time, is unusually evocative and it would be good to read a novel worthy of such a title, e.g., a narrative about two intersecting timelines or an account of a real historical turning point like World War I but with insight into how events could have taken a different course.
Miesel lists four of Anderson's works that have "...Holmesian aspects..." (p. 250) but, of these, "Time Patrol" is surely the best both in its presentation of Holmes on a case mentioned but not recounted by Watson and as a new work in its own right. This single story must introduce the variable timeline, the Nine, the Danellians, the Patrol, its Academy, its Temporal language, Manse Everard, his first trips to the past, our first sight of a time criminal, Everard's promotion to Unattached status and his New York apartment that will become a familiar setting as the series progresses.
Miesel also writes:
"Besides composing interesting alternate history scenarios, [Anderson] achieves the subtler feat of historical transubstantiation: in 'Brave to Be a King' events remain the same but the reason they occur changes." (p. 249)
Well, recorded history remains the same although many unrecorded details differ: another man plays the role of Cyrus the Great. "Historical transubstantiation" might better describe some of the stunts pulled in There Will Be Time, with its invariable timeline. A time travel group recruits a handful of prospects, including Havig and Boris, in Jerusalem on the estimated day of the Crucifixion. Later on his world-line, Havig works against that group and sends Boris to Jerusalem to infiltrate it... Thus, we might say that, in Havig's experience, Boris' presence in Jerusalem is transubstantiated. No discernible detail can be or has been altered but the significance of Boris' trip to Jerusalem is inwardly transformed.
Reasons for traveling to the day of the Crucifixion:
to witness the Crucifixion;
to try to prevent it;
to meet other time travelers;
to recruit time travelers;
to infiltrate the group recruiting time travelers.
Boris turns out to have the fifth, not the first, reason.
Miesel rightly states that, although The Guardians Of Time "...is only one book...it reflects [Anderson's] essential principles..." (p. 251) - as also does There Will be Time, which she mentions but does not have space to discuss here:
the Patrol conserves whereas Havig's group liberates;
the Patrol prevents Neldorians, Exaltationists, individual time criminals and quantum fluctuations from changing the past whereas Havig's group prevents the Eyrie from dominating the future;
Patrol agents ride streamlined updates of Wells' Time Machine whereas Havig shares the Time Traveler's experience of external events flickering past;
Patrollers can change past events whereas Havig cannot but instead must ingeniously change their significance;
the Patrol leads to the Danellians whereas Havig's group leads to the Star Masters;
Everard learns that the Patrol, even though it too changes the past, is "The Only Game In Town" (story title) while Havig's recruits learn that "...Havig's was the only game in town." (There Will be Time, New York, 1973, p. 156)
Miesel characterizes Anderson's four time travel volumes to date:
the Time Patrol employs well-briefed agents;
The Corridors Of Time shows "...unprepared people hurled into strangeness..." (p. 246);
There Will Be Time shows time travel by "...psi talent" (p. 247);
The Dancer From Atlantis "...recreat[es] a real historical milieu..." (pp. 247-248).
The Dancer... is more directly about unprepared people hurled into a strange past and The Corridors... also shows well-briefed agents of time traveling organizations. Five time travel stories are mentioned among several other "time transit" works. Thus, "Of Time And The Rover" is a brief but comprehensive survey.