1. Before extracting in this order as to what is the question of law involved, it is better I trace the facts preceding to the filing of this revision. The revision petitioners are the tenants and the respondent is the landlord and their respective rights are protected under the Tamil Nadu Buildings (Lease & Rent Control) Act, 1960, as amended by Act 23 of 1973 and Act 1 of 1980, hereinafter referred to as the Rent Act. The premises in question is non-residential in nature. The contractual rent was Rs. 1, 750.00 per month. The landlord filed R.C.O.P. No. 2177 of 1985 before the Rent Controller, Madras, under Section 4 of the Rent Act. That petition was filed on 17. 1985. By order dated 14. 1988, the Rent Controller fixed the fair rent at Rs. 6, 335.00 per month. The tenants filed R.C.A. No. 360 of 1988 questioning the correctness of the abovereferred to order. The landlord not satisfied with the quantum of fair rent, filed R.C.A. No.464 of 1988. On 11. 1990, the Appellate Authority passed a common judgment dismissing the appeal fixed by the tenants and allowing the appeal filed by the landlord and thus fixed the fair rent at Rs.7, 479.00 per month payable with effect from