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Tattvarthasutra
Jambudvīpa is like a plate, with a circumference resembling that of a bracelet, and the shape of all the islands and oceans is circular. Jambudvīpa is the foremost of all islands and oceans, meaning no island or ocean is enclosed by it. The area of Kshudraka is ten lakh yojanas. It is circular; however, like salt, it does not have the shape of a bracelet but is similar to a potter's wheel. In its center lies Mount Meru. The description of Meru is summarized as follows: the height of Meru is one lakh yojanas, of which a part equivalent to one thousand yojanas is underground, that is, invisible, while nine thousand yojanas of it is above the ground. The part that is one thousand yojanas underground has a length and breadth of ten thousand yojanas each; however, the outer part above it, from which the cord protrudes, is one thousand thousand chaturanjanas long and wide. There are three sections of Meru. These three sections are submerged in the lake and surrounded by four forests. The first section is one thousand yojanas long, the second is sixty-three thousand yojanas, and the third is thirty-six thousand yojanas long.
In the first section, there are pure earth and gravel, in the second are silver and crystal, and in the third, there is more gold. The names of the four forests are Bhadrashala, Nandan, Saumanas, and Panduka, in that order. After one lakh yojanas of height, there is one cord on top.