JUDGMENT

SARKARIA, J.:— These two appeals on certificate arise out of a common judgment and decree, dated January 18, 1966, of a Division Bench of the High Court of Allahabad. The facts material to these appeals may be set out as under

2. M/s. Hindustan Metal Industries, respondent herein, (hereinafter called the plaintiff) is a registered partnership firm carrying on the business of manufacturing brass and German silver utensils at Mirzapur. M/s. Biswanath Prasad Radhey Shyam, appellant herein, (hereinafter called the defendant) is a concern carrying on the business of manufacturing dishes and utensils in Mirzapur.

3. On August 8, 1953, the plaintiff instituted a suit for injunction and damages, preceded by a notice served on the defendant on September 9, 1952, in the Court of the District Judge, Allahabad, within whose jurisdiction Mirzapur is situated, with these allegations.

4. The old method of manufacturing utensils, particularly shallow dishes, was to turn scrap and polish them on some sort of headstock without a tailstock, the utensils either being fixed to the headstock by thermaplastic cement or held in the jaws of a chuck fixed to the headstock. This system was, however, fraught with risk to the workers inasmuch as the utensils used to fly off from the headstock. Consequently, with a view to introduce improvement, convenience, speed, safety and better finish, Parsottam Dass, one of the partners of the plaintiff-firm, invented a device and method for the manufacture of utensils, in 1951. The plaintiff after filing the necessary specifications and claims in the Patent Office, got the alleged invention patented under the Indian Patents and Designs Act, 1911 (hereinafter called the Act), at No, 46368-51 on May 6, 1953 with effect from December 13, 1951 as assignee of the said patent. By virtue of this patent, the plaintiff acquired the sole and exclusive right of using this method and means for the manufacture of utensils. In September 1952, the plaintiff learnt that the defendant was using and employing the device and method of manufacturing dishes under the formers patent. The plaintiff served a notice upon the defendant asking him to desist from infringing the plaintiffs patent, but the defendant continued to infringe the patent.

5. On the preceding facts, the plaintiff prayed for a permanent injunction restraining the defendant from adopting, imitating, employing or in any manner infringing the device of the plaintiffs patent. The plaintiff further prayed for a mandatory injunction requiring the defendant to destroy the articles used for the infringement of its patent. The plaintiff further claimed a decree for Rs. 3,000/- as damages.

6. The defendant resisted the suit on various grounds, out of those which are material for the decision of these appeals are: that the defendants firm is an old concern carrying on the manufacture of metal wares since long, that the method covered by the plaintiffs patent namely, that of a lathe (headstock, adapter and tailstock) has been known and openly and commonly in use in the commercial world all over the country for several decades before the plaintiffs patent; that the alleged invention of the plaintiff was not on the date of the patent, a manner of new manufacture or improvement, nor did it involve any inventive step or ingenuity regard to what was known or used prior to the date of the patent; and that the patent has no utility and therefore it was liable to be revoked.

7. The defendant also filed a counter-claim, praying for revocation of the patent on the same grounds which he had set out in the written statement.

8. On October 13, 1953, the defendant along with three other business concerns, filed a petition under Section 26 of the Act for revocation of the patent that had been granted to M/s. Hindustan Metal Industries, Mirzapur on the same grounds which were raised in his counter-claim in the suit for injunction and damages.-

9. The Plaintiffs suit along with the counter-claim o