For a moment or two before the spell took effect, he was aware of all the sounds...

For a moment or two before the spell took effect, he was aware of all the sounds around him: rain splashing on metal and leather, and running down canvas; horses shuffling and snorting; Englishmen singing and Scotsmen playing bagpipes; two Welsh soldiers arguing over the proper interpretation of a Bible passage; the Scottish captain, John Kincaid, entertaining the American savages and teaching them to drink tea {presumably with the idea that once a man had learnt to drink tea, the other habits and qualities that make up a Briton would naturally follow}.
Then silence. Men and horses began to disappear, few by few at first, and then more quickly – hundreds, thousands of them vanishing from sight. Great gaps appeared among the close-packed soldiers. A little further to the east an entire regiment was gone, leaving a hole the size of Hanover-square. Where, moments before, all had been life, conversation and activity, there was now nothing but the rain and the twilight and the waving stalks of rye. Strange wiped his mouth because he felt sick.