JUDGMENT

PUNCHHI, J.:- These four appeals by special leave have roots in Bolani Ores Ltd. v. State of Orissa (1 975) 2 SCR 138. These are directed against the common judgment of the High Court of Orissa dated 30th August, 1976 passed in Original Jurisdiction Cases Nos. 1266, 1267, 1222 and 1166 of 1975 : (reported in 1977 Tax LR 1894). Since the appellants have a common cause, these appeals can conveniently be disposed of by a common judgement without resorting to individual facts of each case.

2. The appellants are limited companies engaged in mining activities in the State of Orissa. They hold large tracts of land in that State for the purpose. They have earmarked or enclosed these areas by various means, such as putting up of boundary pillars, erection of check-gates, digging of trenches, etc. They have also constructed approach roads in those areas to facilitate their mining operations. No member of the public is allowed to enter those lease-hold premises without prior permission. In order to carry out their activities the appellants put to use machinery within their lease-hold areas, of a variety. But instantly we are concerned directly with two of them, i.e., Dumpers of various denominations, and Rockers, which seemingly are similar to Dumpers but are heavier than those. Dumpers and Rockers, are known to carry bulk goods, building materials, mining products, agricultural and forestry products, earth, stones, bricks, concrete, mortar, etc., their structure being of simple design and easy to handle. Tripping is performed by releasing the locking device retaining tipping body. The Dumper requires no more than a few seconds for the emptying of its tipping body and gives no trouble to the driver when being operated on uphill or downhill roads, with its load unbalanced or when the load refuses to slide out easily. The description of the aforesaid machines have been taken from Bolani Ores case (AIR 1975 SC 17).

3. Somewhere in the year l961,the appellants, in one form or the other, were asked by the State of Orissa through its officers to register their aforesaid machines as vehicles under the Motor Vehicles Act, 1939 (hereinafter referred to as the Act) and to pay tax under Section 6 of the Bihar and Orissa Motor Vehicles Taxation Act, 1930 (hereinafter referred to as the Taxation Act), as amended up to date. Similar demands were made in areas which stood transferred to the State of Orissa from the Presidency of Madras, where a sister enactment, known as the Madras Vehicles (Taxation) Act, 1931, as amended up to date was applicable, on the same lines, and at par with the Taxation Act. (Henceforth reference to the Taxation Act shall mean reference to both the statutes). Not only for the afore-mentioned types of vehicles were the appellants asked to seek registration under the Act and to pay tax under the Taxation Act, similar demands were made for other vehicles in their possession and use, with which we are presently not concerned. Suffice it to mention that at some stage or the other uptill the stage of the High Court, there were some vehicles to which the State of Orissa conceded that the provisions of one or the other Act did not apply to others it was judiciously held not to apply. It is the remaining types of vehicles which gave cause to this Court to pronounce upon their nature in Bolani Ores case (AIR 1975 SC 17) in the context of the statutes. This Court ruled that Dumpers and Rockers though registrable under the Act were not taxable under the Taxation Act as long as they are working solely within the premises of the respective owners. So far as Tractsteprs were concerned, this Court ruled that they are neither registrable under the Act nor taxable under the Taxation Act. The question about the constitutional validity of the Taxation Act, then raised by Bolani Ores Ltd. (one of the appellants herein) was not dealt with because it was considered academic.

4. As has been the legislative history, the Act and the Taxation Act