Marching to the front on the day before the Somme offensive, Stephen Wraysford leads his company down a track across farmland and comes upon something odd: "two dozen men, naked to the waist, digging a hole thirty yards square at the side of the path". What could be its agricultural purpose? "Then he realised what it was. They were digging a mass grave." A moment later, his men see it too. "The songs died on their lips and the air was reclaimed by the birds." Someone higher up knows what is coming. Songs "die" and men will, almost as readily.
Birdsong has to imagine mechanised slaughter. In the description of the first day of the Battle of the Somme, death comes so thick that the narrative cannot pause for individuals. "Bodies were starting to pile and clog the progress." Stephen watches as a line of troops comes forward "in extended order" into the range of German machine guns, "which traversed them with studied care until every man had gone down in a diagonal line from first to last."
Characters often die in novels, but in this novel deaths cannot be handled in any conventional novelistic manner. The soldiers at the front have learnt not to be shocked, not even to be emotional, at any particular person's death, and the manner of narration has to reflect this. Deaths are narrated through the eyes of particular characters with a numbed factuality. From Stephen's original platoon, only three men remain alive at the front. "The names and faces of the others were already indistinct in his memory." Sometimes he recalled "a voice, a smile, a habitual trick of speech", but these are like dismembered aspects of personality rather than clues to any distinct individuals. This is a war in which explosives can reduce men "to particles so small that only the wind carried them". Tens of thousands of men simply go missing, their names recorded on monuments such as the arch at Thiépval, which so shocks Stephen's grand-daughter Elizabeth in the section of the novel set in the 1970s: "names teeming, reeling, over surfaces of yards, of hundreds of yards, over furlongs of stone". The novel kindles indignation by imitating this oblivion.
It is not just a matter of realism, it is also a manipulation of the reader's sympathies. At the front, anyone can die at any moment. In one battle, Stephen finds himself fighting desperately alongside a fellow officer called Ellis, and trying to talk him out of despair. Reinforcements arrive just in time, and Stephen retires with his men to their own trench. "Ellis had been killed by machine gun fire." We heard him speaking a few lines earlier, but his death is noted in passing. Caring about a character will not save him. One of the other characters into whose thoughts we are taken is Michael Weir, whom Stephen befriends. In one chapter we accompany Weir on home leave, and painfully witness his faltering attempts to describe his experiences to his father, who wants to hear nothing about his son's ordeal. The novel carefully acquaints you with this nervous, intelligent, fearful man, but then it kills him almost casually. As Weir walks towards him one day, Stephen notices that some parapet sandbags have become misplaced and is about to warn him. "Weir climbed on to the firestep to let a ration party go past and a sniper's bullet entered his head above the eye, causing trails of his brain to loop out on to the sandbags of the parados behind him."
After all the deaths that he has seen around him, Jack Firebrace thinks himself "immune to death". He imagines that he will inevitably survive, but also that death cannot any longer touch him. No sooner does he have this thought than something happens to change it. He receives a letter from his wife, Margaret, in which she mentions that their only child, John, "has been very poorly indeed and the doctor says it is diphtheria". The very wording of the letter heightens his – and our – apprehensions. "I am sorry to bother you with the news but I think it is for the best."
The novelist painfully manipulates the reader's emotions. Among so many deaths, the possible death of this eight-year-old boy, whom we know only through the character's intense affection for him, is the one that affects us. When Jack receives a subsequent letter from his wife, he keeps it unopened during his next mission, as if keeping his son alive that bit longer. Of course the child is dead, and his father's every reason for imagining his own survival dissolves.
• John Mullan is professor of English at University College London.
