Kielezo cha Insha is the earliest guide to essay writing in Kiswahili, published by Wits University Press in 1954. After Tanzania's independence in 1961 the book was not available for several decades because of the political and economic sanctions against the apartheid regime in South Africa.

The book covers pertinent issues in composition writing, including the purpose and types of composition, preparation, structure, language and style, cohesion, objectivity and punctuation. It includes 60 model essays together with Robert's thoughts and perspectives on the issues he addresses. The topics include some of the issues current at the time, such as;secret marriages, culture, the environment, language and nationhood, patriotism, womens oppression, health, and the meaning of life and death.

After being out of print for more than sixty years, Wits University Press has reissued the text as a testament to its enduring historical value. Kielezo cha Insha is an example of Robert's educational and pedagogical writing at its best.