Four machines crossed the lines on the expedition; where is the fourth? The crew of the other three do not know. They last saw the missing craft ten miles behind the Boche trenches, where it turned west after sending up a Very's light to signal the necessity of an immediate return. There were no Huns in sight, so the cause must have been engine trouble. The shadows of the lost pilot and observer darken the first ten minutes at the dinner-table. However, since cheerfulness is beyond godliness, we will take this to be an anxious occasion with a happy ending. Comes a welcome message from the orderly officer, saying that the pilot has phoned. His reason for leaving the patrol was that his engine went dud. Later it petered out altogether, so that he was forced to glide down and land near a battery of our howitzers. The conversational atmosphere now lightens. Some people from another squadron are our guests, and with them we exchange the latest flying gossip. The other day, X rammed a machine after his gun had jambed. Y has been given the Military Cross. Archie has sent west two machines of the eleventeenth squadron. While on his way home, with no more ammunition, Z was attacked by a fast scout. He grabbed a Very's pistol and fired at the Boche a succession of lights, red, white, and green. The Boche, taking the rockets for a signal from a decoy machine, or from some new form of British frightfulness, promptly retired. Dinner over, the usual crowd settle around the card-table, and the gramophone churns out the same old tunes. There is some dissension between a man who likes music and another who prefers rag-time. Number one leads off with the Peer Gynt Suite, and number two counters with the record that choruses: "Hello, how are you?" From the babel of yarning emerges the voice of our licensed liar-- "So I told the General he was the sort of bloke who ate tripe and gargled with his beer." "Flush," calls a poker player. "Give us a kiss, give us a kiss, by wireless," pleads the gramophone. "Good-night, chaps. See you over Cambrai." This from a departing guest. Chorus--"Good-night, old bean." A somewhat wild evening ends with a sing-song, of which the star number is a ballad to the tune of "Tarpaulin Jacket," handed down from the pre-war days of the Flying Corps, and beginning-- "The young aviator was dying, And as 'neath the wreckage he lay (he lay), To the A.M.'s assembled around him These last parting words he did say: 'Take the cylinders out of my kidneys, The connecting-rod out of my brain (my brain), From the small of my back take the crank-shaft. And assemble the engine again.'" On turning in we give the sky a final scour. It is non-committal on the subject of to-morrow's weather. The night is dark, the moon is at her last quarter, only a few stars glimmer.