John Pratt (archdeacon of Calcutta)

A gifted mathematician who worked on problems of geodesy and earth science, he was approached by the Surveyor General of India to examine the errors in surveys resulting from the attraction of the plumb-line to the mass of the Himalayan mountains.

His exact date of birth is debated and it is thought that he was born in London as he was baptised on 30 June 1809 at St Mary Woolnoth.

After the death of Bishop Cotton in 1866, Pratt started a Hill Schools' Nomination Endowment Fund to help support Bishop Cotton's scheme of starting schools in the pleasant climate of the hills for the benefit of the children of poorer English residents in India who could not afford an education in England.

[5][10] Pratt was the author of Mathematical Principles of Mechanical Philosophy (1836), subsequently expanded and renamed On Attractions, Laplace's Functions and the Figure of the Earth (1860, 1861, and 1865).

The fundamental goal of the text is to supply an answer to the question as to whether the earth acquired its present form from originally being in a fluid state.

[11] The book is organised in two parts, the first takes Newton's law of universal gravitation as starting point, calculates the resulting force exerted at a point by a total mass in forms ranging from sphere to spheroid and subsequently to an irregular mass consisting of nearly spherical layers approximating more and more to the case of the earth.

[12] Even as he travelled to India in 1838 aboard the Duke of Buccleuch he conducted experiments to examine currents in the ocean and measured temperatures at various depths.

Airy did not defend his view but Samuel Haughton used the debate to claim that mathematics was a useless tool for speculation.

[20] He examined arches,[21] the physics involved in the sudden movement of a mass of water such as in the Indus floods of 1858 and in the bore of the Hooghly river,[22] and computed the iron required for cantilever bridges.

[23] Pratt took a great interest in Hindu Astronomy and supported the translation of the Siddhānta Shiromani, aiding its publication by the authors Lancelot Wilkinson and Pandit Bapu Deva Sastri in 1863.

[25] Pratt however felt that both Indian and Arab astronomy had failed to build a mathematical or physical framework and that their only major achievement was limited to the prediction of eclipses and even these, he considered as imprecise.

[27] In 1856, Pratt published a book entitled Scripture and Science not at Variance, which went through numerous editions; it was first written to counter a statement by the mathematician Baden Powell (father of the scouting pioneer) that "all geology is contrary to Scripture", and then went on to counter other scientific theories including that of Evolution that were thought to conflict with the Bible.