Normal Temperatures

* Body temperature rises and falls through the day, hitting the low at around 6 a.m. when a person awakens and reaching its peak around 4 or 5 p.m.

* The brain and liver are the hottest internal organs. The metabolism in the brain produces so much heat it is as if a 15-watt light bulb were burning in the skull night and day. The blood flowing to the brain cools it down.

* Normal skin temperature is about 90 degrees Fahrenheit, though the forehead can be 90 and the feet 72, and that will still feel comfortable.

* Humans are most comfortable when the external temperatures are about 80 degrees Fahrenehit when naked, and between 68 and 72 degrees when dressed. In cold weather, when the hands and feet reach 65 degrees, they begin to hurt.

* Dogs and cats have a normal temperature of 100 to 102.5 degrees Fahrenheit. Some Tibetan monks can raise their skin temperatures 15 degrees through meditation. Danger Levels

* Infants can have seizures (though brain damage rarely follows) at internal temperatures higher than 105. In everyone, at 115 degree temperatures the body's proteins -- including essential enzymes -- denature. That is, they literally come apart as tissue actually burns. However, there are recorded cases of adults hitting temperatures as high as 114.8 degrees with no ill effects.

* At 94 degrees Fahrenheit, the brain loses its ability to regulate temperature and hypothermia sets in; at 91 degrees a person will lose consciousness.

* The stress of fever can be hazardous to those with heart disease as well as to the very old or very young, whose regulatory systems are not in peak condition.

* If an infant under 4 months of age runs a temperature over 101, consult a physician.

* If a child older than 4 months runs a fever higher than 101 for more than 24 hours, consult a physician.

*Even if there is no high fever in the child, if there are other troublesome symptoms, such as earache, rash, sore throat, extreme lethargy, breathing troubles, vomiting or diarrhea, a physician should be contacted.

* Do not use aspirin to reduce a fever in a child with chicken pox or virus because of the risk of Reye's syndrome.

* If aspirin is advised by a physician, avoid those containing caffeine (such as Excedrin and Anacin), which interfere with the fever-reducing action.

* With fever, drink plenty of liquids. For every two degrees above normal, the body generates one quart of sweat per hour. That fluid has to be replaced for the body to continue functioning normally. Keeping Cool

* Wear loose-fitting cotton or other natural fibers to allow sweat to evaporate and cool down the body. Layers of clothes can be removed to adjust when moving from the air-conditioned buildings to warmer temperatures. Expose pulse-points -- the skin at the wrist, neck, elbow and knee, where vessels are closest to the surface.

* Get fit -- it increases sweating capacity and regulatory efficiency.

* Avoid coffee -- it constricts blood vessels when the body is trying to expand them to loose heat.

* Drink plenty of cool water. Children and the elderly especially run the risk of dehydration as their bodies try to cope with heat. And the cool water actually helps cools down the body from the inside.

* Avoid enclosed spaces. In 90 degree heat, a parked car with closed windows can reach 130 to 140 degrees in 15 minutes. If the humidity is high, danger increases because the body cannot lose as much heat through evaporation of sweat. Keeping Warm

* Wear layers of thick natural fibers. Cotton next to the skin is most comfortable.

* The thicker (fluffier is better than heavier) the materials, the more air is trapped and the better the insulation. Get fit -- it improves circulation and regulatory efficiency.

* Don't drink alcohol -- it dilates blood vessels, causing the body to lose heat. Don't stay in one position long -- movement generates heat.

* If sitting in one place in the cold -- say at a sports event -- sit on styrofoam or a pillow so as not to lose body heat directly to the bench.