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Cycle of Fire

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After his ship crashed on the inhospitable planet Abyorman, Nils Kruger had spent weeks wandering across the face of the planet.suffering from blistering heat, the searing cold of an alien climate. Now he had found a fellow wanderer, Dar, an alien castaway. They may both die. The human opts to do something about it. Dar, who knows the time of his death in advance, opts to do nothing. Which of them is right? Perhaps both?

185 pages, Mass Market Paperback

First published January 1, 1957

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About the author

Hal Clement

178 books115 followers
Harry Clement Stubbs better known by the pen name Hal Clement , was an American science fiction writer and a leader of the hard science fiction subgenre.

Further details at Wikipedia.

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5 stars
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191 (38%)
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155 (31%)
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40 (8%)
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Displaying 1 - 30 of 46 reviews
Profile Image for Roddy Williams.
862 reviews41 followers
July 2, 2016
Hal Clement's genius was in his talent to write rounded likeable characters and set them into a background of realistically thought out planets and environments.
This is no exception and can be seen as a kind of bridge between Stanley G Weinbaum's 'A Martian Odyssey' and Barry B Longyear's 'Enemy Mine'.
Young Nils Kruger finds himself stranded on alien world. He had earlier become separated from his colleagues on a survey expedition and they now believe him dead.
This world is highly volcanic and part of the complex orbit of one planet and two suns.
Not far away is Dar Lang Ahn, an alien male whose glider crashed while he was travelling back to his home in the Ice Ramparts carrying valuable books for his people.
Nils finds the alien sick and dehydrated, and shows him how to get water from the analogue cactus plants that stud the desert, which makes Nils suspect that Dar might not be a native of this world either.
Communicating at first in gestures and drawings, the two begin their journey toward safety and knowledge of each other.
Clement throws in cosmological and anthropological mysteries along the way which are not fully explained until quite near the end.
To a certain extent novels like this shame many of today's writers who, it seems, can't be bothered to world build or create credible alien lifecycles, preferring to employ 'Star Trek' aliens who are essentially humanoid with two genders - although they may be lizards or birds - or just human with a few bumpy ridges on their noses.
Clement does worldbuilding in the truest sense and this is almost a masterclass in designing a species that has evolved to survive on a world with an eccentric orbit involving two suns.
The bonus is that it is also highly enjoyable.
Profile Image for Steven.
425 reviews16 followers
June 6, 2010
First I am amazed that Cycle of Fire was written in 1957, prior to satellites and any real space flight. It is truly science fiction. In this case though, there is far more science than fiction. A space opera it is not.

The story is really slow. It is rare that I felt any true empathy with any of the main characters. I did fee curiosity as to which way the story would turn. All turns were very slow. The science, or rather the exposition of ideas, was more important than the plot.

There are many things that don’t gel. For instance crossbows are pervasive. But animals on which to use them are non-existent. And Dar’s people are basically peace loving. Perhaps the bows are there to capture the imagination of the teenage boys of 1957, its primary audience.

I enjoyed the book for several reasons. It took me back to what I used to enjoy in science fiction. It made me appreciate how very different science fiction is today; it isn’t necessarily better. A child reading this may be intrigued by ideas. A person reading today’s works will more likely be taken with the story, the action. That seems sad to me.

Most of what I enjoyed is external to the book itself. So I will only give it a three. None-the-less, it is very much worth the read.
Profile Image for Xabi1990.
2,126 reviews1,387 followers
March 14, 2019
Leído en 2003.
Un humano que se queda varado en un planeta y conoce a un indígena, no humano, y se las tiene que ingeniar para sobrevivir.

Muy entretenido de leer, la historia no es hoy original …pero en el 57, cuando fue escrita, tenía su punto. Interrelación entre dos especies, no superioridad de la humana, problemas de comunicación e interpretación de la forma de ser y de pensar del otro. Problemas recurrentes en la CF que se extrapolan siempre al distinto, al extraño, a las sociedades y grupos humanos.
Venga, que no me enrollo pero que me gustó. Tiene su parte "hard" en la última parte del libro.
Profile Image for Gregoire.
1,097 reviews45 followers
July 9, 2016
je suis vraiment fan de Hal CLEMENT Ce petit livre recouvre en moins de 200 pages les thèmes majeurs de la SF scientifiques Des aliens vraiment alien ; une écologie crédible ; des tentatives de communications entre deux 'naufragés" : un jeune humain curieux et débrouillard et un alien différent mais attachant ; l'auteur passant de l'un à l'autre avec bonheur
Le seul hic, c'est le style un peu "suranné" de la SF des années 1960

Lire en anglais les commentaires de Roddy Williams ou de Charles Harrison qui vont à l'essentiel et que je rejoins complétement.


Profile Image for Rock Howard.
18 reviews
April 14, 2018
Clement is a Golden Age master of hard science fiction. In this novel he creates a fantastic world that hosts a brilliant biological example of life finding a way. At its heart this is a human/alien buddy/survival story of the highest order. It is also a reminder that great SF does not necessarily require wars or crimes or love affairs to hold the intelligent readers attention. Curiosity and exploration is quite enough.
Profile Image for Vilius.
204 reviews34 followers
January 14, 2020
Klasikinė hard SF. Be romano "Ugnies ciklas" knygoje dar 2 apsakymai. Visų trijų kūrinių tema tolimų planetų tyrinėjimas ir kontaktas su nežemiškomis rasėmis. Pats "Ugnies ciklas" visai patiko, bet apsakymai pasirodė nuobodoki, labai jau sausi.

"Kritinis taškas" - 2/5
"Ugnies ciklas" - 4/5
"Apsikeitimo greitis" - 2/5
Profile Image for Стефан Русинов.
Author 17 books233 followers
Read
July 26, 2015
Много ми е вълнуващо да чета за друг свят, развил се при различни условия, с живот, стекъл се по невъобразим за мен начин. Познатата реалност ми става крехка, чуплива, чудна и смайващо случайна. А и в крайна сметка всеки човек е друг свят, развил се при различни условия, с живот, стекъл се по невъобразим за мен начин. В момента насочвам солидни дози от възхищението си тъкмо към хората, способни да създадат и съживят такъв свят. Разбира се, в по-широк смисъл всеки умел писател е способен на това. Създаването на цяла планета обаче си е подвиг от особено висок ранг в моята книга.

Прочетена и осмислена изцяло на глас с добра компания.

Правите линии в рисунките на Текла Алексиева ме разбиват.
Profile Image for Jose Moa.
519 reviews79 followers
June 25, 2016
Hal Clement was one of the fathers of the hard sf,his most famous novel is Mission of Gravity in the Mesklin series.This novel dont belong to that series.

This novel,written in 1957,has the same charm as Mission of Gravity and is a very valuable classic hard sf novel for several reasons.

In the plot is developped the no so common friendship between a stranded human in an alien earthlike planet and an alien inteligent being.The planet has two suns,it orbits a small red sun that at the same time orbits a blue giant in a very eliptical orbit,the blue giant,in the Pleyades open cluster has recently captured (in geological times)the red star.
All this gives way to a convoluted climatology and series of seasons that has molded the evolution of life in the planet.

For all is a original novel and rigurous in the treatment of astronomy,planetology and evolution of life,also has moral questions about transference of advanced technology to alien cultures,has emotional moments and touchs the subject of the acceptance the own dead in fixed time.

Has the added value that the reader is progressively discovering the misteries and enigmas of the planet and native civilization,a civilization original in its suprvivence in hard climatological environement and in its exotic way of reproductive sistem.

A novel over a credible planet,credible exobiology,credible civilization and that i have enjoyed so much or perhaps more that Mission of Gravity and one of the more original classic hard sf novel i have read.

And taking account that now is known about exoplanets,a novel ahead of its time
Profile Image for Иван Иванов.
144 reviews4 followers
September 26, 2021
Разочароваща книга. Винаги съм харесвал темата за контакта и опознаване на чужда планета, но тук тя е разработена ужасяващо скучно. Голяма част от текста е от типа "герой А обяснява нещо на герой Б" (обикновено под формата на дълъг монолог), което може да е вървяло навремето, но днес просто не се търпи. Досадната описателност оставя всички интересни идеи на заден план, така че много скоро престана изобщо да ми пука за тях и дочетох книгата по диагонал.
Profile Image for Rog Petersen.
160 reviews3 followers
November 21, 2025
These leading characters are not as charming as those of Mission of Gravity, but this book is almost as likable. Though Clement’s scientific info-dumps can be jarring.
Profile Image for A.L. Sirois.
Author 32 books24 followers
March 7, 2022
I like Hal Clement's science fiction, even though he really isn't all that good with characters. He created a number of fascinating worlds, and because he had a solid background in science, he really knew how to make alien worlds convincing. His aliens are never really convincing, though, because their psychologies are indistinguishable from humans'. Again, I don't care, because he was able to contrive interesting adventures. In this book, 16-year-old Nils Kruger is accidentally marooned on Abyorman, a planet circling a red dwarf star that in turn circles a blue giant star. This makes for some VERY extreme changes in climate, so extreme that the planet hosts two entirely different forms of intelligent life, one that has evolved to withstand Abyorman's "cold" cycle, and one that thrives during the "hot" cycle. Kruger befriends one of the "cold form" aliens, Dar Lang Ahn, and together they set out for Dar's original goal. Along the way they become friends, but Kruger is going to learn that Dar not only knows the precise day he will die, the alien pities Kruger because he does NOT know the date of his death. Even stranger, there are very good reasons for Dar's determination to reach the Ice Ramparts before he dies -- and reasons why the cold and hot forms of Abyorman's life are completely dependent on each other. CYCLE OF FIRE isn't as good as Clement's best books, which in my opinion are MISSION OF GRAVITY and NEEDLE, but it's fun nevertheless, and the ecosystem of Abyorman is nothing if not peculiar. Classic science fiction, a diverting read as long as you're not looking for deep characterization.
Profile Image for Jerry.
Author 10 books27 followers
August 23, 2024
This book, especially toward the end, is filled with technical explanations, and I have never seen it handled in such an entertaining manner. Hal Clement excels when he’s given room to write. Cycle of Fire is even more enjoyable than Mission of Gravity.

The basic story: a pilot on the planet Abyorman crashes due to volcanic activity, and must walk a thousand miles to deliver the very important books before he dies. Meanwhile, a cadet from Earth was left for dead after falling into a mud pit.

In what appears to be one of Clement’s trademarks, the two races are very different, and the bulk of the book is mostly a mystery: how does Abyorman exist, and how do the people who live on it make sense?

Clement has a conversational narrative style that turns this into as much a documentary about this very real place as it is an adventure story. This, I suspect, is what makes the long descriptions so enjoyable. He’s like the invisible voice narrating some true historical event.
Profile Image for Craig.
6,333 reviews178 followers
April 24, 2020
Cycle of Fire suffered a bit by always being overshadowed by his classics Needle and Mission of Gravity, but it's a very good novel in its own right. Clement's forte was in designing alien environments and alien life forms to inhabit them, and then devising convincing ways in which humans could interact with the life forms and survive the hostile conditions. In Cycle of Fire a human explorer is marooned on a hostile world and soon joins forces with a fellow castaway, who happens to be nonhuman. The story of their collaboration and cooperation in facing the trials and tests make for an excellent hard-sf read.
319 reviews1 follower
April 29, 2016
A true alien novel. This book could double as a guide to first contact, alien ecology, survival and alien archeology. The races are detailed and interesting with very alien motivations. Throw in Clement's usual flair for clever chemistry, biology and physics and you get something truly brilliant. This is hard sci fi at its best which left me thinking about it for days afterwards. Perhaps not the fastest paced adventure but a perfect example of a hard science fiction thought experiment.
Profile Image for Bill.
414 reviews104 followers
January 6, 2010
Another fascinating story by the father of hard SF. Human, Nils Kruger, stranded on a planet with a cometary orbit around the lesser of a binary star in the Pleiades cluster, survive by cooperating with native Dar. A friendship develops and through their adventures and with the help of starship scientists discover the truth of the strange biology on this planet of fire and ice. Classic Clement!
Profile Image for Will Boncher.
622 reviews13 followers
February 23, 2017
Top-notch scifi. Definitely a focus on the science side of it, but that's just how I like it. Kept me excited the whole time. Pretty quick read, now I have to look into more of his books.
Profile Image for Ints Brunenieks.
255 reviews25 followers
November 28, 2021
No jaunības dienām bija palikusi atmiņā kā lieliska fantastikas grāmata.
Pirmo stāstu atcerējos, tāpēc lasīju bez intrigas, bet ar citu ienteresētību. Lasi gan jāsaka, ka tomēr tagad jau esmu izlutināts lasītājs.
Nevar noliegt autora talantu uzburt nākotnes pasaules ļoti ticamā veidolā. Planēta ar divām saulēm, dienu ilgumu un ritējumu pavisam atšķirīgu no Zemes. Arī pavisam citādākas saprātīgās būtnes. Paiet laiks, kamēr saproti un ppierodi, ka saprātīgās būtnes nepavisam nav līdzīgas cilvēkiem. Tām nav divas rokas un kājas, tām maņu orgāni ir pavisam savādāki, pat krāsas tie uztver pavisam savādāk.
Pasaule var būt pavisam savādāka, nekā mēs esam pieraduši redzēt un sajust. Ar to arī tā pasaule ir forša.
Profile Image for Adi.
977 reviews
December 6, 2020
In a world located five hundred light years away from Earth, two creatures from different species meet and start their journey. Nils Kruger and Dar Lang Ahn are aliens to one another, yet they understand that they need to work together in order to survive and accomplish their missions. It was nice to see how a true friendship can evolve between two completely different forms of life, especially on a planet, which is so strange and cryptic.
The three starts come from the fact that the action was substantially decreased in the last third of the book, compensated by extensive biological, evolutionary, astronomical and so on explanations.
Profile Image for Даниел Иванов.
Author 6 books23 followers
April 25, 2018
Приятна книжка, но не е напълно мой тип. Имаше доста моменти, които ми допаднаха, но последните 50 стр. ги дочетох на инат.
Profile Image for Roger.
203 reviews11 followers
November 10, 2025
This is what science fiction is supposed to be. Loved it.
Profile Image for 2Due.
78 reviews3 followers
May 23, 2022
This has been my second book from Hal Clement and the more I read, the more I love the man's style.
I'm fresh from Mission of Gravity and I admit I was expecting something similar in Cycle of Fire, in some terms, it has been and thankfully in others has been not, I didn't want to read the same story twice.
It started a bit slow, but I was captured immediately the moment I see this little alien risking his life to save some precious books and I thought "I like this guy."
The characters have a very interesting dynamic and seeing them learning and bonding is a delight and their adventure is intriguing. Unfortunately the pacing is a bit odd, or at least that's how I felt it, might call it even a bit dated to today's standards. For 2/3 of the book I couldn't really grasp the "Two civilisations: the existence of each dependent on the death of the other" because I couldn't see which were the civilisations, the humans and the abyormenites? The abyormenites and the Teachers? Something felt missing.
The plot cranked up full speed when we got introduced to the "hot" Teachers and I swear I was glued to the pages. I had started to suspect there was some predator-prey relationship somewhere, but in reality it was a parasite-host situation, making the "hot" Teachers indeed very creepy and the acceptance by the abyormenites to the cycle fascinating and -to human's view- sad. I cried at the end.
I wish the last third of the book was more expanded, but it was still very satisfying.
I'm a proud owner of a Corgi Books copy and a signed Del Rey copy of this book, both little gems in my collection. Huge shoutout to Doug Miller Books in Toronto, Canada for providing the signed book!
This entire review has been hidden because of spoilers.
Profile Image for Samantha.
363 reviews22 followers
August 2, 2022
Review: Cycle of Fire
By: Hal Clement
4.5/5 ⭐️ (torn between 4 & 5)
👽
“Each was a stranger to the other, but which was the alien?”
👽
This was my first time reading Hal Clement and it won’t be my last! The story starts off as a first contact meet and greet, but soon leads into a masterful evolution and science based plot. Hal created intriguing characters that form a genuine connection and continue for the generations that will follow. I highly recommend this to anyone who loved Project Hail Mary! It has very similar themes and will prove a memorable experience for the alien lovers at heart.
Profile Image for Deydre.
49 reviews14 followers
December 29, 2023
Me ha gustado mucho.
Creo que es un libro muy gradual en cuanto a toda la información que da, va de menos a más poquito a poco y al final te encuentras con una barbaridad de información algo difícil de asimilar. Esto último es lo único que me ha chocado, ya que me he encontrado con algunas explicaciones y términos que me ha costado entender. Aunque estoy acostumbrada a este tipo de explicaciones en otros libros de scifi, creo que, aunque no se pone del todo técnico, el autor sí "sobreinforma" un poco, al menos al final del libro.

Por lo demás me ha encantado la relación entre los dos protas y cómo va evolucionando, con sus similitudes y diferencias. También me gusta cómo se describe el entorno y los biomas en los que se encuentran, aunque personalmente me gusta algo más de profundidad, siempre dejando lugar a la imaginación.

La historia en sí es maravillosa y toda la información que se da de un planeta y seres muy distintos a lo que conocemos me parece fascinante. Creo que se trata con mucho mimo y está muy bien pensado, a diferencia de otros libros donde no terminas de creerte mucho cómo funciona todo.

En resumen, recomiendo el libro porque es entretenido, engancha desde el principio y te va acumulando muchas incógnitas hasta el final.
1,247 reviews
August 18, 2022
Hal Clement excels at creating aliens with an extremely different biology and life view from us but which we can still relate to. The alien race in this book, we learn partway through it, gets almost completely exterminated every 80-some earth years as the planet's temperature and atmosphere change drastically due to its eccentric orbit, but from their bodies, another morph of aliens is born which lives during the times of fire, and almost entirely dies out at the end of that period. The story is engaging, but there is a great deal of explanation of the science involved, which towards the end of the book especially slows it down a great deal.
Profile Image for Brent Byron.
81 reviews
May 27, 2021
My favorite Hal Clement so far. Great adventure, great science. A unique set of aliens that will blow your mind as always, and the best part is the signature good feeling and cooperation that permeates all of his works. You will never guess how the abyorminite's physiology and ecosystem work. The question "when do you die?"asked commonly by the abyormin natives, almost as a greeting, is one part the mystery that's laid out in pieces throughout the book and ties nicely together at the end.
Profile Image for zjakkelien.
764 reviews22 followers
July 18, 2021
Perhaps it was partially personal circumstances, but this book didn't draw me in quite as much as I had hoped. Dar and Kruger are friends, and I had hoped for that to be more strongly present, more emotionally present. It was clearly there, but it seemed to take second place to the discovery of the workings of the planet and the native people. The dilemma surrounding Dar is readily resolved and does not involve Kruger's friendship, which seemed a bit too easy for me.
Profile Image for Thomas.
2,690 reviews
November 17, 2025
An alien and a human learn to communicate and survive on a planet with an extreme climate.

Harry Stubbs, who wrote under the pen name Hal Clement, was a high school science teacher. I would love to have had a course from him.

I remember giving this masterpiece of hard sci-fi a rave review when I was in the eighth grade. I still do.
Profile Image for Bibi.
33 reviews
June 6, 2017
Interesting! A heady mix of SF and fantasy :)
Profile Image for Tim Robinson.
1,095 reviews55 followers
November 22, 2017
Neither the characters, nor the events, nor the science, nor the plot is sufficiently interesting to carry this book. Disappointing.
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