( 1 ) THREE quarters of a century back, on or about 20-8-1878, the appellants' predecessors took permanent settlement of the underground rights in the lands in suit from the respondents' predecessors. The relevant kabuliyat which was described as a "mokrari Taluka Kabuliyat" was duly registered in accordance with law and a certified copy thereof is Ext. 1 in the present case. It appears from the kabuliyat (Ext. 1) that the lessees had also certain rights in the corresponding surface land. A selami of Rs. 5,039/8/- was paid at the time of the settlement and the annual rent or jama was fixed at "company's current sicca Rs. 503978/-". This total rent was mentioned in the schedule of the kabuliyat as "rs. 5,039/8/-" and was payable in eleven kists or instalments of Rs. 420/- each in each of the months of Bhadra to Asar of each Bengali year and a twelfth monthly kist or instalment of Rs. 419/8/-in Sraban following. The lessees stipulated for themselves and their heirs to pay the lessors and their heirs "the fixed rent, year after year, month after month, according to the kists" stated above, with a further stipulation that "on failure of the kists, we shall pay inte