SETHURAMAN, J.

This appeal has been filed against the order of the Board of Revenue dated 21st December, 1976. The assessee is a dealer in senna leaves, senna pods, etc. For the year 1969-70 he returned total and taxable turnovers of Rs. 14, 00, 307.92 and Rs. 22, 106.28 respectively. In the turnover of Rs. 14, 00, 307.92 was included a sum of Rs. 11, 50, 175.99, which related to export sales and Rs. 2, 07, 625.65 which related to inter-State sales. After allowing a deduction in respect of the said turnover, the Deputy Commercial Tax Officer, Tuticorin-1, determined the taxable turnover at Rs. 42, 506.28, assessable under section 3(1) of the Tamil Nadu General Sales Tax Act, 1959. He also found that the dealer had exported 50, 832 kgs. of senna leaves and pods to foreign countries after 27th November, 1969, and the purchases of senna leaves and pods were not supported by vouchers. As the purchases had not suffered tax at any earlier stage, he estimated the purchase turnover at Re. 1 per kilogram and brought the sum of Rs. 50.832 to tax under section 7-A of the Act. On appeal, the Appellate Assistant Commissioner relied on a decision of this Court in M. K. Kandaswami v. S