1. This a suit for a declaration that the assessment of a rate under Section 85(b), Bengal Municipal Act (3 of 1884) on the annual value of the plaintiff-appellant's holding by the Commissioners of the Panihati Municipality was ultra vires and illegal.
2. The decision turns upon the true construction of Section 101 of the Act which runs as follows:
101. The gross annual rent at which any holding may be reasonably expected to let shall be deemed to be the annual value thereof and such value shall accordingly be determined by the Commissioner, and entered in the valuation list; provided that (except in the Darjeeling Municipality) if there be on a holding any building or buildings the actual cost of erection of which can be ascertained or estimated the annual value of such holding shall in no case be deemed to exceed an amount which would be equal to seven and a half per centum on such cost, in addition to a reasonable ground rent for the land comprised in the holding.
3. It appears that the holding in suit is debuttar property held by the plaintiff as shebait. The area of the holding is about 13 bighas, of which half consists of a fruit orchard; upon 3 bighas there are 12 Shiva mandirs, and upon the remainder of the holding stand the three-storied dwelling house and offices forming the residence of the plaintiff. The property is situate on the east bank of the Hooghly about eleven miles up the river from Calcutta, with a pucca ghat leading to the river.
4. In 1921 for the purposes of a latrine tax imposed under Section 86 of the Act the annual value of the holding was assessed under Section 96 at Rs. 3,750 and in 1924 when the rate in question was imposed under Section 85(b), it is conceded that no separate or further valuation of the holding was made, and that the assessment was based upon the annual value that had been ascertained for the purpose of the latrine tax in 1921.
5. Now, the holding in suit is of a similar nature to that of numerous other properties on the banks of the Hooghly that are used as the residences or pleasure houses of prosperous citizens of Calcutta. The plaintiff's son in the course of his evidence at the trial stated that houses of this type in the neighbourhood of the plaintiff's holding rarely were let, and usually were occupied by the owners who had built or acquired them. But there was evidence that specific holdings of a similar nature in the vicinity had been let, and that such properties from time to time changed hands, and passed from one owner to another.
6. Nevertheless, it appears that in 1921 when the valuation list was prepared no attempt was made by the officer appointed to value the holdings to ascertain the annual rent at which the plaintiff's holding might reasonably be expected to let, or to obtain information as to the cost of the construction of the buildings that had been erected on the holding. All that the valuation officer purported to do was to estimate 'by guess' what he conceived to be the cost of erecting the buildings that he found on the holding and to settle the valuation upon the estimate thus made. The Commissioners appear to have accepted the basis of the valuation officer's estimate and assessment was fixed at 3 per cent on an annual value of Rs. 3,750.
7. If the assessment as made was ultra vires and illegal it cannot be sustained and the plaintiff is entitled to the relief that he seeks Chairman, Municipal Board, Chapra v. Basudeo Narain Singh  37 Cal. 374.
8. On behalf of the respondents it is contended that the assessment can be supported upon the footing that Section 101 and proviso 1 thereto contain alternative modes of assessment, and that it is open to the municipality to assess a holding either upon the annual value ascertained as set out in Section 101 or upon a percentage basis under the proviso.
9. In my opinion the construction which the respondents urge upon the Court cannot be accepted. The general rule for construing provisos was explained by the House of Lords in West Derby Union v. Metropolitan Life Assurance Society  A.C. 647 in which case Lord Herschell observed:
I decline to read into any enactment words which are not to be found there and which would alter its operative effect because of provisos to be found in any provision. Of course, a proviso may be used to guide you in the selection of one or other of two possible constructions of the words to be found in the enactment, and show when there is doubt about its scope, when it may reasonably admit of doubt as to its having this scope or that, what is the proper view to take of it but to find in it an enacting provision which enables something to be done which is not to be found in the enactment itself on any reasonable construction of it, simply because otherwise the proviso would be meaningless and senseless would, as I have said, be in the highest decree dangerous: ibid p. 655.
and Lord Davey added:
It seems to me that the, whole argument of the appellants really comes to the old and apparently ineradicable fallacy of importing into an enactment which is expressed in clear and unambiguous language something which is not contained in it, by what is called implication from the language of a proviso which may or may not have a moaning of-its own: ibid, p. 657.
10. The meaning and effect of Section 85(b) and Section 101, however, in my opinion, is clear and in accordance with the general principles of rating, and these sections provide that in every case the rate is to be imposed on the annual value of the holding which is deemed to be the gross annual rent at which the holding 'may be reasonably expected to let,' while the proviso was inserted in aid of the assessee, and to lay down a maximum to prevent excessive assessments being made. In the present case no attempt was made to ascertain the annual value of the plaintiff's holding as provided by Section 101, and in my opinion the Commissioners were acting ultra vires in accepting the valuation officer's method of valuation
based as they knew it was, upon a percentage of the estimated cost of the building in entire disregard of the principle which they were bound by law to adopt as the basis of their assessment:' see Per Garth, C.J. in Nundo Lal Bose v. Corporation of Calcutta  11 Cal. 275 (at p. 281).
11. I am not unaware that since Nundo Lal Bose's case was decided on 19th February 1885 by Section 151(b), Calcutta Municipal Act (3 of 1899), for the purpose of assessing land and buildings to the consolidated rate
the annual value of any building, not erected for letting purposes and not ordinarily let shall be deemd to be
a sum ascertained with reference to a percentage on the costs of construction as therein provided, and that since the judgment of Cave and Wills, JJ. in Queen v. School Board for London  55 L.J.M.C. 55 delivered on 21st December 1885, although
a certain rate of interest on the capital expended in creating the hereditament is by no means to be taken as necessarily equivalent to the rent which a hypothetical tenant would give...the amount of capital expended is admissible in evidence as a criterion by which to estimste that rent in the case of works like these (i.e., a public reservoir) which are incapable of being compared with other hereditaments which form the subject of letting:.' Per A.L. Smith, L.J. in Liverpool Corporation v. Llanfyllin Assessment Committee  2 Q.B. 14 (at p. 21): see also Per Buckley, L.J. in Liverpool Corporation v. Chorely Assessment Committee and Whitnell Overseers  1 K.B. 270, Metropolitan Water Board v. Chertsey Union  1 A.C. 337.
12. No doubt in exceptional cases where the rent that a hypothetical tenant might reasonably be expected to pay for the holding cannot be ascertained by methods which would be efficaious in normal and ordinary cases, for example, where the holding consists of land upon which a railway a gas works, a catchment area or a building such as the Bodleian Library at Oxford is situate, rough and ready tests alone may be available for ascertaining the annual rent that a hypothetical tenant of the holding might reasonably be expected to pay, but in every case the annual rental value is the basis of the assessment, and in such exceptional cases, as Mr. Ryde points out in his work on Eating (Edn. 2 at p. 176)
a great part, if not the whole, of the difficulty will disappear if the rule be thus stated; the measure of rateable value is defined by statute as the rent which may reasonably be expected; interest on cost, or on capital value cannot be substituted for the statutory measure but can be looked at as prima facie evidence in order to answer the question of fact what rent a (tenant may reasonably be expected to pay.
13. Now, applying these principles to the facts of the present case I am of opinion that the plaintiff's holding is not to be regarded or treated as though it were of an exceptional or abnormal type, for as Garth, C.J. pointed out:
the principle of rating upon which the Commissioners are directed to proceed is the same as that which is adopted in England, and similar difficulties arise there in the case of gentlemen's parks and mansions which are laid out for residential purposes, and not for letting. But such properties are, never the less, constantly rated upon the basis of their annual letting value, Nundo Lal's case  11 Cal. 275.
14. In my opinion in the present case the Commissioners were not justified in departing from the basis assessment laid down in Section 101, and, while it is not the duty of this Court to instruct the Commissioners as to how assessments should be made provided they adopt the methods prescribed in the Act, it appears to me that if the persons authorized to make the assessment apply their minds to the matter in hand no difficulty ought to be experienced in ascertaining according to the provisions of the Act 'the gross annual rent at which the plaintiff's holding 'may be reasonably expected to let.'
15. For these reasons, in my opinion, the decrees of the lower Courts must be set aside and a decree passed for a declaration that the assessment on the appellant's holding was ultra vires and illegal as prayed. The appellant is entitled to Ms costs in all the Courts.
16. I agree.