Radhanath Sikdar

Radhanath Sikdar was a smart man from India. He loved math from a young age. He used math to study the shape of the earth.

He worked on a big survey project. He looked at many mountain peaks. He found the tallest one in the world. This mountain is called Mount Everest.

He figured out how high the mountain was. He was the first person to do this. He also helped teach women. He started a journal to help them learn.

Radhanath was a very important thinker.

Radhanath Sikdar was a brilliant mathematician from India. He was born in 1813. He showed a great talent for math as a boy. A professor noticed his skill. The professor helped him learn even more.

Sikdar worked on a big project called the Great Trigonometric Survey. His job was to be a "computer." Back then, a computer was a person who did hard math. He used math to study the shape of the Earth. He even made up his own ways to measure things.

In 1852, he did something amazing. He used math to find the tallest mountain in the world. He looked at many pieces of data. He found that Peak XV was the tallest. We now call this mountain Mount Everest. He calculated its height was 29,000 feet.

Sikdar also cared about helping people. In 1854, he started a journal. This journal helped teach women in India. He was a very important thinker. He was even named a member of a science group in Germany. His work helped us understand our world much better.

Radhanath Sikdar was a gifted mathematician from India. He was born on October 5, 1813, in Calcutta. His father, Tituram Sikdar, worked as a clerk. Radhanath showed a special talent for numbers very early in life. A professor named John Tytler noticed his skill at Hindu College. Tytler became a mentor to help him grow. Radhanath was even one of the first two Indians to read Isaac Newton's famous book, the *Principia*.

Sikdar worked on a massive project called the Great Trigonometric Survey. In 1831, George Everest was looking for a math expert. He needed someone who knew spherical trigonometry to help map the land. John Tytler recommended his 18-year-old student, Radhanath. Sikdar joined the team on December 19, 1831. His job title was "computer." This meant he was a person who did hard math by hand. He earned thirty rupees every month for his work.

In 1852, Sikdar made a discovery that changed how we see the world. He was tasked with measuring the height of mountains. At first, people thought Kangchenjunga was the tallest mountain. Radhanath looked at six different observations of a peak called Peak XV. His math showed that this peak was actually the highest. He calculated the height to be exactly 29,000 feet. This mountain is the one we now call Mount Everest.

Sikdar was more than just a math expert. He also wanted to help people in his community. In 1854, he and Peary Chand Mitra started a journal called *Masik Patrika*. This journal was made to help educate Indian women. He was also a social reformer. He once paid a fine of 200 rupees in 1843 to protest for workers. Later, he taught math at the General Assembly's Institution.

Many people remember his great work today. In 1864, a science group in Germany made him a member. The Indian government even put his face on a postage stamp in 2004. We can see how his math helps us even now. Mount Everest actually grows by 4 mm every single year. Modern climbers and new tools help us find even better measurements. His work helped us understand the shape of our Earth.

Radhanath Sikdar was a brilliant Indian mathematician and a dedicated social reformer. He is most famous for being the first person to calculate the height of Mount Everest. This massive achievement occurred in 1852 through his expert use of mathematics. Beyond his scientific work, he was a member of the Young Bengal group. He also worked to improve society through education and advocacy. His life combined deep scientific study with a desire to help others.

Sikdar grew up in a Bengali Brahmin family in Calcutta. He was born on October 5, 1813, to Tituram Sikdar and Deviki Sikdar. His father worked as a clerk to support the family. From a very young age, Radhanath showed an exceptional talent for mathematics. This skill caught the attention of John Tytler, a professor at Hindu College. Tytler became an important mentor for Sikdar's intellectual growth. This early support helped him master very difficult mathematical concepts.

By the time he was a teenager, Sikdar was already performing advanced work. He was one of the first two Indians to read Isaac Newton's *Principia*. He also studied Euclid's *Elements* and various texts on geometry and astronomy. As a young student, he even invented a new method for drawing a common tangent to two circles. These achievements led him to join the Great Trigonometric Survey in 1831. He was hired as a "computer," which was a job title for someone performing complex calculations by hand. He earned a salary of thirty rupees per month.

His work involved geodetic surveys, which is the study of the Earth's geometric shape. This field looks at how the Earth is oriented in space and how gravity works. Sikdar did not just follow old methods; he invented his own to improve accuracy. He worked alongside seven other Bengali computers in Sironj near Dehradun. Because of his superior skills, he became a favorite colleague of George Everest. In 1851, he was promoted to Chief Computer and moved to Calcutta. He also served as a superintendent for the Meteorological Department.

In 1852, Sikdar performed the calculations that changed geography forever. At the time, many believed Kangchenjunga was the tallest mountain in the world. Following orders from Colonel Andrew Scott Waugh, Sikdar began measuring mountain heights. He analyzed six different observations regarding a mountain known as Peak XV. His mathematical results proved that this peak was actually the highest. He calculated the height to be exactly 29,000 feet. Although Waugh added two feet to the figure to avoid it looking like a rounded number, Sikdar's discovery was the true foundation.

Sikdar's mathematical legacy remained significant for many decades. His 29,000-foot calculation stood until 1955, when an Indian survey measured it at 29,029 feet. Today, we know that Mount Everest is constantly changing. The peak grows at a rate of 4 mm every year. It is also slowly moving toward the northeast. Modern technology and data from thousands of climbers provide even more precise details. These advancements continue the work that Sikdar began with his hand calculations.

Sikdar was also a man of strong principles and social concern. In 1854, he and Peary Chand Mitra founded *Masik Patrika*. This was a Bengali journal designed to educate and empower Indian women. He also stood up for the rights of others. In 1843, he was fined 200 rupees for protesting against the unfair treatment of survey workers. Later in life, he taught mathematics at the General Assembly's Institution. He died on May 17, 1870, in Chandernagore.

His genius has been recognized by many different groups over the years. In 1864, the German Philosophical Society's Bavaria branch named him a Corresponding Member. In 2004, the Indian government honored him on a postage stamp. This stamp celebrated the Great Trigonometric Survey and featured Sikdar's likeness. His life shows how mathematics can help us understand the very shape of our world. He remains a vital figure in the history of both science and social progress.