The Smog by John Creasey

breathing exercises in front of an open window, rain or fine, hot or cold.”
    â€œMist has been fairly thick, sometimes,” Marion told them. “But—yellow? No, I don’t remember—” She leaned back in her chair, eyes half-closed, as if trying to remember. “It has sometimes appeared very thick—grey and opaque, Dr. Palfrey. I am not an inveterate early riser, but on nights when I sleep badly I often get up about dawn.”
    â€œMy room doesn’t overlook the village,” said Storr. “Yours does, Philip.”
    â€œ I’ve never noticed anything either yellow or brown.” Philip’s voice was sulky.
    â€œMr. Costain,” Palfrey said. “You’re up early every morning, aren’t you?”
    â€œI think—” began Costain.
    â€œYou know, it has been yellow once or twice,” Marion interrupted. “Not thick, nothing like it was yesterday, but yellowish.”
    â€œI was going to say there has been a yellow tinge on some mornings,” Costain said.
    â€œAh!” exclaimed Palfrey. “Can you say what morning?”
    â€œI remember one day in the winter, just after the first snow, when there were some slippery patches and Joe Taylor had a spill on his motorcycle. He was going too fast, and—”
    He stopped abruptly, for Joe Taylor and his son were both dead; both had died yesterday, in their barn, just inside the contaminated area.
    â€œI remember that morning,” Marion put in, quietly. “It was more yellow.”
    â€œDid you notice any smell?”
    She didn’t answer at first, but Costain put in with a slow excitement: “There was a smell of carbon monoxide!”
    â€œ Imagination, ”muttered Philip.
    â€œThe motorcycle ended up in the hedge but its engine didn’t stop,” went on Costain. “I remember distinctly. I saw the accident from the top of the hill.”
    â€œI heard the engine,” Marion put in. “I couldn’t understand what it was, but Taylor told me afterwards. I could smell the exhaust, too.”
    â€œYou—from half-way up the hill?” Griselda was sceptical.
    â€œFrom half-way up the hill—but it didn’t really surprise me,” Marion went on. She had a pleasant voice but it held none of the almost histrionic resonance of her sister’s. “With the wind blowing from the village we often get—”
    â€œFarm odours,” supplied Costain drily.
    â€œWell, we do. ”
    â€œYes, I know. I will have to find a—” he stopped. It was obvious that everyone of them had the same thought as he: there would never be a chance to experiment, there wasn’t a single animal left alive. He moistened his lips.
    â€œI have known the perfume of the blossom from the apple orchard to be very strong, especially in the evenings,” put in Storr, gently. “And that is nearly half a mile away. It does depend entirely on the direction of the wind.”
    â€œYou know,” said Marion, slowly, “there was a yellowish morning in the village a few weeks ago. I remember it vividly now. The wind had cut in during the night and I was closing the window. The exhaust fumes almost knocked me back.”
    â€œMissed your daily dozen?” asked Griselda sceptically.
    â€œNo, I went in the Professor’s room—he was in London that week.”
    â€œMy room is across the landing, and faces south,” explained Storr, again.
    â€œWas there any smell from the south?” asked Palfrey.
    â€œNo. No! ”cried Marion, almost excited in her effort to recall everything that had happened. “No smell, but that was when I heard the engine popping. And the motorcycle was north from the Manor, and the wind was coming from the opposite direction, so the smell I noticed wasn’t coming from motorcycle exhaust. Do you know I hadn’t realised that before.”
    She looked triumphantly into