Anak Krakatoa Lesson Summary and Explanation in English Class 6th


Krakatoa is an island in the Sunda Strait between Java and Sumatra in Indonesia. It is known for its volcano which erupts regularly. The chapter is a concise and informative piece on this volcano.

What is a Volcano?

A volcano is a crack in the earth’s crust that opens up. Near the earth’s core, there is hot molten rock. It occasionally rises to the earth’s surface and spills out via such a fissure or breach. When this happens, the volcano is said to have erupted. Volcanic eruptions occur on a massive scale. 

 Thick clouds of smoke rise high into the sky from the entrance. The breach in the earth spews large, incandescent chunks of rock and red-hot lava. Mud and ash are also thrown out. Landforms in an area can be altered by a large volcanic eruption.

Volcanoes are popularly classified into three categories with the first being active volcanoes, that erupt regularly. The second type is dormant volcanoes, which are temporarily inactive or in a deep sleep. The third category is extinct volcanoes. An extinct volcano is unlikely to erupt again. Long ago, they used to erupt, but there is no record of it in history.

Disastrous Krakatoa

Krakatoa is an active volcano and its worst eruption occurred in August 1883. Its boom was heard as far as 3500km in Australia making it believed to be the loudest sound that man has ever heard. The island, which had formerly been a volcanic mountain, caved in on itself. The dust spewed up by the explosion soared to a height of roughly 80 kilometres in the sky. It stretched throughout the sky, eventually settling in different parts of the world.

The eruption caused tsunamis and destroyed around 165 villages, also destroying two-thirds of the island of Krakatoa. It sank beneath the sea’s surface, forming a massive underwater volcano crater that was more than 6 kilometres in diameter. In 1927, a column of smoke billowed from the crater’s water.

There was another eruption after that. The volcanic material that erupted from the crater was not completely absorbed by the waves, and a new mountain began to grow. It kept growing and soon rose above the water. Thus, a new island grew from the old island of Krakatoa. It was named ‘Anak Krakatoa’ or the ‘Child of Krakatoa’.

Eruptions have again begun since 1994 and since 1950, the island has grown at an average rate of 5 inches per week. After Krakatoa’s eruption in 1883, all life ceased to exist and when a scientist visited it in 1884, he found just one spider there. But life on Rakata, which is a part of the old island renewed.

The wind and the sea brought seeds of plants to the island. Plants and animals began to inhabit one of the island’s edges. It was similar to a laboratory where scientists could see how living things evolve over time in a given location. Scientists can now see this new growth of life in regions of Anak Krakatoa that are not buried in volcanic ash.


The eruption of Krakatoa wreaked havoc on Java’s western shore. There were only a few people who remained. However, the number of wild animals and vegetation in that area flourished once more. In reality, because there were no humans to interfere with the wildlife’s growth, it did so organically. There was no one to cut down trees or kill the animals. As a result, wildlife prospered in this area.