How Does A Firefly (Glow-Worm) Glow at Night?

The glowing fireflies at night present a wonderful spectacle. Children love to see it. Scientists have been engaged from the very beginning to find out how and why fireflies emit light.

The firefly is, in fact, a flying worm. Both the male and the female of this worm have wings They are blackish and their bodies are very soft. They mainly live on the nectar of the flowers. They are found in larger numbers in tropical areas. Light is emitted in flashes by them. The light producing part is located in the bottom of the belly in the rear side and controlled by nerves.

Firefly.

Firefly.

It contains two chemicals named 'luciferin' and 'luciferase'. Luciferin combines with oxygen to produce light. Luciferase helps in this combination i.e., acts like a catalyst. It is interesting to note that no heat is produced by the light emitted by them. Such a process of production of light is called 'bio-luminescence'. Luciferin is the active luminescent material in the fireflies.

bio-luminescence.

bio-luminescence.

The light emitted by the fireflies is either yellow or orange. Today scientists can produce such lights in their laboratories. But that is done by extracting luciferin and luciferase from the fireflies only.

Now the question is: Why does the firefly produce light?  

The first possible reason is that both the male and the female fireflies emit light to attract each other. The second reason may be that the light so produced may frighten birds and prevent them from attacking the fireflies. Whatever may be the reason for this but everybody is enchanted to see them at night.

Fireflies glows at Night.

Fireflies glows at Night.

"Fireflies Are Stars That Could Not Journey To The Sky."  ---Michael B. Johnson.---

How Do We Find Direction In The Sea?

In the beginning, when man made boats, he also used them for the sea travel But he had not dare to travel too far because the beat of losing his way as he did not have any instrument to find the directions in the sea. During those days, the sea travelers used to take the help of the sun and the stars to find different directions. But when the sun and the stars were not visible in the cloudy weather, finding the right direction was very difficult. 

About one thousand years B.C., a black stone with peculiar properties was discovered at Magnesia in Asia Minor. It used to attract small iron pieces. This stone was named as "Magnet". It was also observed that a freely suspended magnet always points towards the north and south. It is because the earth itself is a huge magnet and as such attracts the poles of the magnet. The Chinese navigators utilized this property of the natural magnet, around the year 1300,to know about the directions in the sea. This is how the first compass of the world was made. 

Magnetic Compass.

Magnetic Compass.

In the primitive compasses a cork or a piece of wood used to be floated in a water bowl and a piece of the magnetic stone placed on it. The ends of the stone always pointed towards The north-south direction and thus helped in finding the directions.

With the progress of the science, man has developed artificial methods to make magnets of iron and steel which are being utilize in developing many kinds of magnetic compasses.

The modern compasses consist of a small non-metallic box with a thick paper dial. The paper is divided into four right angles, and N.S.W. and E. representing North, South, West and East directions are marked on it. Each quarter of the circle is further divided into "eight" equal parts. In this way the whole circle is divided into 32 parts. In the center of this circle a magnetic needle is pivoted which freely rotates in a horizontal direction. It is covered with a glass plate. The magnet pointing in the north-south direction helps the navigators to determine the direction in which the ship is sailing.  

In many big ships nowadays another kind of instrument named "Gyro-Compass"is also "Sed". It is also used in airplanes to determine the direction.

"On The Ocean of Life Let Your Mind be the Ship and Your Heart be the Compass." - James D. Manning.