S.S.SANDHAWALIA, J.

1. Whether a writ of mandamus can or should issue for a claim of money simpliciter- is the significant issue which arises at the very threshold of this case admitted directly to a hearing by a Full Bench.

2. The facts are not in serious dispute. Thirty-one partnership business firms of Tarn Taran, district Amritsar, have jointly moved this writ petition to claim a writ of mandamus for the refund of unspecified sums of money which are alleged to have been paid by them under a mistake of fact or law to the Market Committee, Tarn Taran. It is the common case that under the earlier unamended Sec. 23 of the Punjab Agricultural Produce Markets Act (hereinafter called the Act) the Market Committees were entitled to levy fee ad valorem at the rate of Rs. 1.50 P. on the purchase or sale of agricultural produce worth Rs. 100 only. By the Ordinance No. 40 of 1974, the aforesaid Sec. 23 was amended and the market fee was raised from Rs. 1.50 P. to Rs 2.25 P. ad valorem. This ordinance was later replaced by the Punjab Agricultural Produce Markets (Amendment) Act No. 13 of 1974 and was given retrospective effect from the date of the issue of the earlier Ordinance. The