Question

what are the differences between the maps prepared by ptolemy or idrisi and the britishers ?

Answer 1

Map drawn by Arab geographer al-Idrisi
a. Map was made in the 12th century. Map was drawn in 1720's.
b. Sri Lanka, an island is shown at the top. South India is placed at the top where we have North India. This is not the case with the map drawn by the French cartographer.
c. Places are marked in Arabic. Places like Kanauj are spelt as Qanauj.

or
Map drawn by French cartographer
a. Map was drawn in 1720's.
b. This is not the case with the map drawn by the French cartographer.
c. This map is more detailed in nature and has a degree of familiarity.

Answer 2

A map of the Indian sub-continent, made by a famous Arab geographer - al-Idrisi -- in 1154, shows south India in the north and Sri Lanka at the top. But another map of the same area made by a French cartographer (a person who makes maps) in 1720 is quite different from what al-Idrisi made.