11.   The burning paper will have warmed the air going up the chimney and thus start the draft going to prevent that early smoking problem.

12.   The intense heat of lightning warms the air immediately surrounding the lightning bolt.

13.   The heat-absorbing roofs and pavement were warming the air, and the hot air was rising, sucking air from all directions into the city.

14.   The researchers expect the air to be warmed by the heat released during condensation, causing the intensity and direction of air currents to change.

15.   The sun began to warm the air, and small caddis flies and early brown stoneflies began fluttering off the river by the dozens.

16.   The technician also can measure how much the air has been warmed as it enters the ducts leading to registers, another measure of efficiency.

17.   The sun is gently warming the air.

18.   They are simply oil-fueled heaters that warm the air.

19.   This will warm the air in the chimney to start a draft going.

20.   Upon its descent onto the Plains, this air is warmed and dried by compression.