Chris Thornley, age 14, of Ottawa, Ont., for his question:

What makes the brain work?

The brain of a big blue whale weighs 20 pounds. An elephant’s brain weighs ten pounds. The brain of a grown man weighs only about three pounds. So it is not the size of the brain that makes for smartness. For man is smarter than any animal, including the big‑brained whales and elephants. No animal can do arithmetic or figure out right from wrong.

However, the animal brain works just like the human brains The grout difference is in the quality and degree of its work. The higher confers of intelligence are far more developed in the brain of man.

Brain tissue is soft. The center is white and the rind or cortex is wrinkled and gray. In man, the cortex is deeply folded and. crinkled like a walnut. Hence he has more gray matter in his brain. And, when it comes to what we call intelligence, this gray matter is important.

The brain itself is headquarters for the nervous systems Nerve cells. connect the entire body in a network like delicate telephone wires. The trunk lines moat in the spinal cord, a sturdy cable of nerves protected by the vertebrae of the backbone. At the top of the neck this cable of nerves fans out. Each group of nerves goes to this or that center of the brain. '

The brain itself is safely encased in the bony skull. Each section of the brain attends to G certain group of nerves from a certain part of the body. Strange to say, the right side of the brain controls newes coming from the left side of the body. An injury to the left side of the brain may paralyze muscles in the right side of the body.

The tongue is controlled. by a part of the brain at the base of the back of the skull. Just above this area is the center which controls the jaw. On top of the brain are centers which control arms, torso and legs. The speech center lies deep within the brain.

There are two 1arge areas of the brain which neither receive nor send messages. They are called the silent areas of the gray cortex, Some experts believe that these are the most vital areas, in which the brain does its figuring and calculating. However, we do not know everything about the brain to be certain. This should not surprise us. We all know that the electronic men‑made brain is a wonderful machine. But such a machine could not compare with a three pound. human brain, even if it were as big as the city of Ottawa.

Nerves carry messages from all over the body to the spinal cord The spinal cord relays these messages to the brain. By some magic of its own the brain sifts and sorts all the facts and makes decisions. The spinal cord and a wad of nerves at the brio of the skull control certain automatic jobs such as breathing and digestion. But most experts believe that intelligence and complex thought is handled by the  cells of the cortex.