Section 81(1) in Chennai City Municipal Corporation Act, 1919
(1)Every contract entered into by the commissioner on behalf of the corporation shall be entered into in such manner and form as would bind him if it were made on his own behalf and may in like manner and form be varied or discharged:Provided that -(a)the common seal of the corporation shall be affixed to every contract which, if made between private persons, would require to be under seal; and(b)every contract for the execution of any work or the supply of any materials or goods which will involve an expenditure exceeding [two thousand rupees] [Substituted for 'One thousand rupees' by Tamil Nadu Act 22 of 1972.] shall be in writing and shall be sealed with the common seal of the corporation and shall specify-(i)the work to be done or the materials or goods to be supplied, as the case may be,(ii)the price to be paid for such work, materials or goods, and(iii)in the case of a contract for work the lime within which the work or specified portions thereof shall be completed.
