“You put two things together that have not been put together before. And the world is changed.”

This book is about coming together and moving apart, of soaring to the sky and slipping into the underworld. It begins with balloonists in the late 19th century, then moves on to a love affair between two of the balloonists before leading to the heart of the book: the death of the author’s wife.

Ballooning was dangerous but liberating, a way of breaking free from constraints, both physical and social. It was, however, a freedom that was subservient to the weather, to the direction and force of the wind, and could easily end in disaster. You could be floating in the sky one moment and flung down to earth the next, knee-deep in a rose bed.

The title of the first chapter, The Sin of Height, has echoes of Icarus, the man who flew too close to the sun which melted the wax on his wings. As the book begins, in Britain and France in the mid- to late 1800s, people are taking to the skies in hot air balloons. The author focuses on three of these balloonists: Colonel Fred Burnaby of the Royal Horse Guards in Britain, and the actress Sarah Bernhardt and photographer Félix Tournachon, better known as Nadar, in France.

All the characters in this book are real. Nadar, one of the early portrait photographers, also combines photography and aeronautics. Unlike his contemporaries, he is more interested in “the vertical” than the horizontal. Even his portraits attempt to plumb the psychological depths of his sitters, which is what makes them so memorable. But images can be formed in other, more ephemeral, ways: such as when Burnaby and his companions in their hot air balloon notice that the sun is projecting their shadows onto a cloud, like a “colossal photograph”.

We come down to earth in the second chapter, On the Level, which is about the affair between Sarah Bernhardt and Fred Burnaby. Bernhardt has conquered the stage in spite of being too small, too pale and too thin (she claims to be able to “slip between raindrops without getting wet”). She is Jewish in an anti-Semitic country and also a bohemian, which appals the puritans. Burnaby is a well-travelled man with no time for conventions. The affair between these two misfits in their worlds feels inevitable and natural—until it ends when Bernhardt moves on to another lover. Burnaby is heartbroken but cannot be angry with her. After all, she had always been honest with him: “on the level”. He eventually marries someone else but never gets over losing Sarah Bernhardt.

This takes us to the third chapter, The Loss of Depth, which is the crux of the book. We are now in the subterranean depths of grief: the loss of love, but in a more final and devastating way. After 30 years of being happily married, Barnes’s wife dies. And this is what the book has been leading up to—the unbearable pain at the loss of a loved one. This chapter is hard to read at times because it is so close to the bone, especially if you have been through the death of someone dear to you.

When I started this book, I wasn’t sure how the author was going to lead up to his wife’s death. But it all fits together. The images of height and depth run through the book: “Life’s sonar is broken and you can no longer tell how deep the seabed lies.” Plummeting several hundred feet when a balloon collapses is not so different from the shock of losing a loved one. (I’m sorry, Julian Barnes, I know you hate the use of the word loss to describe death.)

This gem of a book is an elegant and beautiful tribute to Barnes’s wife, Pat Kavanagh. I’d like to end with a line from the last chapter. Barnes goes back to the image of the three balloonists created by the sun: “And so it is with our life: so clear, so sure, until, for one reason or another—the balloon moves, the cloud disperses, the sun changes angle—the image is lost forever, available only to memory, turned into anecdote.”