Java enjoys a comparatively even temperature the year round. Ninety-six degrees Fahrenheit was recorded in Batavia in 1877 and that is the highest mark known. The lowest was 66 degrees Fahrenheit, which was experienced in the same place in the same year. The mean annual temperature is 79 degrees Fahrenheit, and the difference between the warmest and the coldest months is 1.8 degrees Fahrenheit. The year is divided into two seasons by the prevailing winds—the rainy period, that of the wet monsoon, from November to March, and the dry period the remainder of the year, when the dry monsoon blows. There is no long unbroken rainfall and no long spell of drought. The average rainfall is much greater on the south coast than on the north: in Batavia it is 72.28 inches yearly, while Majalenka has an annual fall of 175 inches. Wind-storms are rare and hardly ever cyclonic, but thunderstorms are of frequent occurrence. Under an almost vertical sun, the day is of nearly uniform length throughout the year. The plains vary in fertility according to their geological formation, but with the exception of the regions abounding in marshes, stretches of disintegrated coral, and lakes, they are tillable and productive. Sugar cane was brought to Java by the Chinese or Hindus in very remote times. The Chinese pilgrim Fa Hien mentions having found sugar there when he visited the island in 424,[85] and as trading was constantly carried on between Arabia, India, China and Java, there is but little doubt that when the secret of boiling the sugar juice to a grain was discovered it became known to all of them at once. About 1520 the Portuguese established trade relations with the natives and early in the seventeenth century the Dutch influence began to make itself felt. The Dutch East India company built forts and set up trading stations in the coast towns; at first it acquired only small pieces of land in Jakatra (Batavia) and it was some time before its holdings were increased. Finally Jakatra was conquered and the Dutch power in Java firmly established. But little was done at the outset to help the sugar industry, as the policy of the Dutch East India company was to foster trade in the products of the East rather than undertake to raise any of the commodities itself. The sugars that were sent by it to the mother country at the beginning of its operations, therefore, came from China, Formosa, Siam and Bengal, and no Javan sugars reached Holland until after 1637, in which year the company decided to establish sugar mills on its own land near Batavia.