3. Where in any suit in respect of any money lent by a money-lender after the commencement of the Usurious Loans Act, 1918, it is found that the interest charged exceeds the rateof fifteen per cent. per annum in the case of a secured loan or twenty-five per cent. per annum in the case of an unsecured loan or that there is a stipulation for rests at intervals of less than six months, the Court shall, until the contrary is proved, presume for the purpose of section 3 of the Usurious Loans Act, 1918, that the interest charged is excessive and that the transaction was harsh and unconscionable and was substantially unfair, but this provision shall be without prejudice to the powers of the Court under the said section where the Court is satisfied that the interest charged, though not exceeding fifteen per cent. per annum or twenty-five per cent. per annum, as the case may be, is excessive.