V. Dutta Gyani, C.J. (Acting)— This writ appeal is directed against the judgment and order dated 8.2.94 as passed by a learned Single Judge of this Court in Civil Rule No. 1936 of 1990. 2. All the appellants are graduates in Science. One of them, appellant No. 14, holds an Honours Degree in Chemistry. They joined the respondent Corporation as Laboratory Assistant in different grades. Some of the appellants were sponsored by the Employment Exchange while others had directly applied in response to the advertisement issued by the respondent Corporation. The appellant Nos.3 and 4 were already in employment of the Corporation, although in other department but on their own options they were transferred and appointed as Laboratory Assistant Grade III. These appellants, claiming equal pay for equal work, filed a petition under Article 226 of the Constitution, ventilating their grievances that their should not be different grades of Laboratory Assistant and they should all be graded in one grade of Laboratory Assistant, they complained of discrimination. The learned Single Judge was, however, not satisfied and dismissed the petition. Hence this appeal. 3. Mr. Bhattacharjee, learned counsel appearing for the appellant contended that since all the grades of Laboratory Assistant including Senior Laboratory Assistant perform identical duties and similar functions with the same measure of responsibility having the same academic qualifications, they were entitled to equal pay on the principle of equal pay for equal work. The practice prevailing in the respondent Corporation is violative of Articles 14 and 16 of the Constitution of India. It was contended that there was no rationale of different grades. 4. The Supreme Court in State of MP & another vs. Pramod Bharatiya & others, AIR 1993 SC 286 , a judgment also relied upon by the learned Single Judge, has while dealing with the question of equal pay for equal work and the definition as contained in section 2 (h) of Equal Remuneration Act of 1976 has explained as follows: "2(h). "Same work or work of a similar nature "means work in respect of which the skill, effort and responsibility required are the same when perform under similar working conditions, by a man or a woman and the difference, if any, between the skill, effort and responsibility required of a man and those required of a woman are not of practical importance in relation to the terms and conditions of employment 12. It would be evident from this definition that the stress is upon the similarity of skill, effort and responsibility when performed under similar conditions. Further, as pointed out by Mukharjee, J (as he then was) in Federation of All India Customs and Excise Stenographers, ( AIR 1988 SC 1291 ) the equality of work may vary from post to post. It may vary from institution to institution. We cannot ignore or overlook this reality. It is not a matter of assumption but one of proof. The respondents (original petitioners) have failed to establish that their duties, responsibilities and functions are similar to those of the non technical Lecturers in Technical Colleges. They have also failed to establish that the distinction between their scale of pay and that of non technical Lecturers working in Technical Schools is either irrational and that it has no basis or that it is vitiate by malafides, either in law or in fact (see the approach adopted in Federation case, ( AIR 1988 SC 1291 ). It must be remembered that since the plea of equal pay for equal work has to be examined with reference to Article 14, the burden is upon the petitioners to establish their right to equal pay, or the plea of discrimination, as the case may be. This burden the original petitioners (respondents herein) have failed to discharge." It has been found by the learned Single Judge as a fact that the duties of the Senior Laboratory Assistant are not the same as that of the Laboratory Assistant. 5. Mr. Deka, learned counsel appearing for the respondents, has invited attention to the affidavit-in-opposition and submitted that the different grades and categories in the post of Laboratory Assistant was required to be created for giving impetus to the employees by way of promotion and the different in scales of pay is also provided with the same object. He also submitted that the duties of Senior Laboratory Assistant and the Laboratory Assistant are different. The Senior Laboratory Assistants are required to perform supervisory duties as well which the Laboratory Assistant in the Grade III are not required to perform. The classification as made is rational. He also submitted that the duties of Senior Laboratory Assistant and the Laboratory Assistant are different. The Senior Laboratory Assistants are required to perform supervisory duties as well which the Laboratory Assistant in the Grade III are not required to perform. The classification as made is rational. Lastly placing reliance on the following judgments, as reported in - (1) AIR 1962 SC1139 (Kishori Mohanlal Bakshi vs. Union of India), (2) AIR 1995 SC 1889 (State of West Bengal & others vs. Deb Kumar Mukharjee & others) he urged that no interference is called for in this appeal. 6. The Supreme Court in Kishori Mohanlal Bakshi (supra) has held as follows: "The only other contention raised is that there is discrimination between Class I and Class II Officers inasmuch as though they do the same kind of work their pay scales are different. This it is said, violates Article 14 of the Constitution. If this contention had any validity, there could be no incremental scales of pay fixed dependent on the duration of an officer's service. The abstract doctrine of equal pay for equal work has nothing to do with Article 14. The contention that Article 14 of the Constitution has been violated therefore, also fails." In State of West Bengal vs. Deb Kumar Mukharjee & others (supra), the Supreme Court while dealing with the case of Inspectors Grade I and II alongwith the Inspectors in the Animal Husbandry Department, who were performing almost identical duties has held as follows: "The duties performed by the Inspectors in the two Grades may be the same, but no fault can be found with the classification. It is settled by a starting of authorities of this Court that classification in the cadre on the ground of selection based on merit is permissible it is well-known in service jurisprudence that selection grade and super time scale based on seniority or seniority-cum-merit are permissible. The High Court fell into patent error in setting aside the Classification on the ground of discrimination." In view of the foregoing discussion, this appeal fails and it is accordingly dismissed.