Where the principal money secured is one hundred rupees or upwards, a mortgage 5[other than a mortgage by deposit of title-deeds], can be effected only by a registered instrument signed by the mortgagor and attested by at least two witnesses.
Where the principal money secured is less than one hundred rupees, a mortgage may be effected either by 6[a registered instrument] signed and attested as aforesaid, or (except in the case of a simple mortgage) by delivery of the property.
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