'Building' is defined in the Act by s. 5 (7) as including "a house, outhouse, stable, hut, shed or other enclosure, whether used as a human dwelling or otherwise and shall include verandahs, fixed platforms, plinths, door-steps, walls and the like." The definition is an inclusive definition, and contains inherent indication that a part of a building would be a building for the purposes of imposition of liability to pay rates, and assessment of such liability. It is manifest that under the scheme of the Act read with the rules, conservancy tax and water rate are to be levied as rates on the gross annual letting value and a rate can only be levied from a person in respect of the tenement or premises occupied as an independent unit. The assessment rules provide for levy of rate on the gross annual letting value of the building, and in as much as the expression 'building' according to the definition given in s. 5 (7) of the Act would include a part of a building, the Corporation is competent to frame a list in respect of several tenements occupied by different persons treating each tenement as a separate building for levy of tax. That is implicit in rule 10 (b) and also in rule, 10 (c) of the assessment rules,