JUDGMENT P. Govindan Nair, J. 1. The question is whether the two petitioners were probationers in the post of Junior Lecturers in the Union Christian College, Alwaye, entitling them to prefer an appeal under sub-s.(7) of S.55 of the Kerala University Act, 1969 (hereinafter referred to as the Act) to the Vice Chancellor of the Kerala University, the 1st respondent to this petition. Though by Ex. P8 order dated 11-12-1970 the 1st respondent held that an appeal under sub-s.(7) of S.55 of the Act to him is competent, by Ex. P9 order dated 19-12-1970 the 1st respondent came to the conclusion that the petitioners were not probationers. 2. Counsel for the petitioners contended that the view taken by the 1st respondent cannot be sustained in view of the amendment to S.55 of the Act which introduced a new sub-section, sub-s.(4) and an explanation thereto. To understand this contention it is necessary to refer to S.55 of the Act as it stood before the amendment as well as sub-s.(4) of S.55 and the explanation thereto as it had been amended by the Kerala University (Amendment) Act, 1971 (hereinafter referred to as the Amending Act) which was published in the Kerala Gazette on the 22nd May, 1971. We shall first extract S.55 of the Act as it stood before the amendment effected by the Amending Act. "55. Probation:-- (1) Teachers of private colleges shall be on probation for a period of one year within a period of two years: Provided that in exceptional cases the period of probation may be extended by a period not exceeding one year, subject to the prior approval of the Syndicate. Explanation:-- Probation undergone by a teacher before the commencement of this Act shall be deemed to be probation for the purposes of this sub-section, provided such probation is within a period of two years immediately before such commencement. (2) The governing body or managing council as the case may be, may, at any time before the prescribed period of probation, terminate the probation of the probationer for want of vacancy and discharge him from service if he appointed by direct recruitment or revert him to his original appointment if the appointment to the new post was by transfer or promotion. (3) Any probationer discharged or reverted under sub-s.(2) shall be given preference in the matter of future appointments to the same post. (3) Any probationer discharged or reverted under sub-s.(2) shall be given preference in the matter of future appointments to the same post. (4) On satisfactory completion of probation, the governing body, or managing council, as the case may be, shall confirm the teacher in the post if the post is substantively vacant, and if the post is not substantively vacant or if the appointment is for a specific period, the teacher shall be allowed to continue for the remaining period of his appointment. (5) If, on the expiry of the prescribed period of probation, the governing body or managing council, as the case may be, decides that the teacher is not suitable for continuance in the post in which he is appointed it shall discharge him from service or revert him to his original appointment as the case may be, after giving I him a reasonable opportunity of showing cause against the action proposed to be taken in regard to him. (6) Where the post held by the probationer is substantively vacant and before the expiry of one month from the prescribed period of probation he is not confirmed under sub-s.(4) or is not discharged or reverted under sub-s.(5), he shall be deemed to have been confirmed in that post. (7) A probationer who is discharged or reverted under sub-s.(5) shall be entitled to appeal against the order of discharge or reversion to the Vice Chancellor within a period of sixty days from the date on which he receives a copy of the order and the order of the Vice Chancellor on such appeal shall be final". Sub-s.(4) and the Explanation introduced by the Amending Act is in these terms: "(4) on satisfactory completion of probation, the educational agency or the corporate managements, as the case may be, shall confirm the teacher in the post if the vacancy is not a substantive vacancy, the teacher shall be allowed to continue in the post for the duration of the vacancy. Explanation:-- All teachers who have been working in a substantive vacancy at or after the commencement of the principal Act shall be deemed to have been on probation for the purposes of this sub-section." 3. The two petitioners were appointed by Exs. P1 and P2 orders dated 21-7-1969 and 23-6-1969 as Junior Lecturers for specific periods, the appointments to terminate automatically on 31-5-1970. The two petitioners were appointed by Exs. P1 and P2 orders dated 21-7-1969 and 23-6-1969 as Junior Lecturers for specific periods, the appointments to terminate automatically on 31-5-1970. The petitioners were told that they would cease to be in employment from 31-5-1970 by Exs. P5 and P6 communications dated 30-4-1970. The petitioners actually ceased to be in service from 1-6-1970. At that time the petitioners were appointed, the Act had come into force and though no Ordinance had been framed under the Act, the Ordinances framed under the earlier Act, the Kerala University Act, 1957, which was in force immediately before the commencement of the Act in so far as the Ordinances were not inconsistent with the provisions of the Act continued to be in force until they were replaced by Ordinances framed under the Act (Vide S.75(2) of the Act). Chap.57 of the Ordinances in Paragraph envisaged appointment of teachers either on a permanent basis, or on probation or a temporary basis or for a specific period. It is clear that the orders Exs. P1 and P2 were orders appointing the two petitioners for specified periods. 4. The argument of counsel for the petitioner is based entirely on the explanation to sub-s.(4) of S.55 which was introduced by the Amending Act. It was contended that by virtue of this explanation, the teachers who were working on the date of commencement of the Act in substantive vacancies had become probationers. This being so, it was further urged that the termination of their services could only be for the reason that they were not suitable for continuance in the post in which they were appointed. Consequently, it was submitted, that the petitioners were entitled to appeal to the Vice Chancellor (Section 55 (7) ) and that the Vice Chancellor should have considered the appeal on the merits and that his view that the petitioners were not probationers is incorrect. 5. We experienced considerable difficulty in understanding the true meaning of sub-s.(4) of S.55 read with the explanation. Without the words "at or after the commencement of the principal Act" in the explanation, the meaning is fairly clear that the explanation will apply only to teachers who were working in a substantive capacity and continued to work in that capacity at the time the explanation came into being, namely on 10-12-1970. Without the words "at or after the commencement of the principal Act" in the explanation, the meaning is fairly clear that the explanation will apply only to teachers who were working in a substantive capacity and continued to work in that capacity at the time the explanation came into being, namely on 10-12-1970. But by the introduction of the words above referred to, we have to give a meaning to "all teachers who have been working in a substantive vacancy at or after the commencement of the principal Act." If the earlier part of the explanation meant that the teachers should have been working in a substantive vacancy and should have continued to work in that capacity till the commencement of the Amending Act, the words "at or after the commencement of the principal Act" becomes nugatory or of no moment because the teachers who have to continue to work would necessarily work at and after the commencement of the principal Act. On a careful consideration it appears that the proper meaning to be given to the explanation is to hold that it will apply only to teachers who continued to work in a substantive vacancy at the time of coming into force of the Amending Act. The general rule is that a statute must be presumed to be prospective in its operation and the onus is on those who seek to establish that it is retrospective in operation to establish that it is so. It can be established either because of the express words in the statute or from the necessary implications arising from the words used in the statute. References had been made to the Supreme Court decisions in Income Tax Officer, Tuticorin v. T. S. Davinath Nadar etc. ( AIR 1968 SC 623 ) and in Ahmedabad Manufacturing and Calico Printing Co. Ltd. v. S. G. Mohta Income Tax Officer and another ( AIR 1963 SC 1436 ) and it was urged that the principles laid down in those decisions would enable the petitioners to establish that the explanation was meant to have retrospective operation. ( AIR 1968 SC 623 ) and in Ahmedabad Manufacturing and Calico Printing Co. Ltd. v. S. G. Mohta Income Tax Officer and another ( AIR 1963 SC 1436 ) and it was urged that the principles laid down in those decisions would enable the petitioners to establish that the explanation was meant to have retrospective operation. There is no doubt that it has retrospective operation in the sense that it will apply to teachers who had been appointed to substantive vacancies before the Amending Act came into force, but will so apply, we think, only if the teacher appointed continued to be in service at the time of the coming into force of the Amending Act. If we hold otherwise, it appears that for the same substantive vacancy, more than one teacher can claim by virtue of this explanation that he is a probationer and therefore entitled to protection. Let us illustrate this. The two petitioners had ceased to be in service from 1-6-1970. We presume that fresh appointments had been made to these vacancies. We shall so assume. The persons so appointed to those vacancies if they continued in service at the time of the Amending Act will be entitled to the benefit of the explanation. If we further hold that the two petitioners also are entitled to those two substantive vacancies it may lead to absurdities as two persons cannot be held to be entitled to a single vacancy. We think the better course would be to understand those who have been working in substantive vacancies as those who worked before the commencement of the Amending Act and continued to work at the commencement of the Amending Act. The words "at or after the commencement of the Principal Act" are only by way of clarification that they worked for the entire period from the date of their appointments. This is the true meaning that we should give to the words in the explanation "teachers who have been working" is clear from the pronouncement of this Court in Kunhammed Keyi v. Premalatha ( 1962 KLT 366 (F.B.) ). We shall extract a passage from the judgment dealing with the true interpretation to be placed on the proviso to sub-s.(2) of S.5 of the Kerala Buildings (Lease and Rent Control) Act. We shall extract a passage from the judgment dealing with the true interpretation to be placed on the proviso to sub-s.(2) of S.5 of the Kerala Buildings (Lease and Rent Control) Act. That proviso was in these terms: "Provided that the fair rent fixed may in proper cases be lower than but shall ( in no case exceed by more than 15 per cent, the monthly rent on the basis of which the property tax or house tax for the building has been fixed." The decision turned on the interpretation to be placed on the words "has been fixed" and the relevant passage is in these terms: The proviso related to the fixing of the fair rent............... (see last paragraph at page 368)................it would be bad English.........." 6. Reference was made by counsel to the decision of the Supreme Court in The State of Bombay v. Vishnu Ramachandra ( AIR 1961 SC 307 ) a decision noticed by the Full Bench of this Court and the passage in Para.13 of the judgment runs thus: "the verb 'has been' is in the present perfect tense, and may mean either 'shall have been' or 'shall be' looking, however, to the scheme of the enactments as a whole and particularly the other portions of it, it is manifest that the former meaning is intended..............." This was said in answer to the contention that S.57 of the Bombay Police Act which opens with the words "if a person has been convicted" will apply only to convictions that took place after the Bombay Police Act came into force. This contention was naturally negatived by the Supreme Court and commenting on the decision, Raman Nayar J. as he then was said in Kunhammed Keyi v. Premalatha ( 1962 KLT 366 ). There the question was whether the words, "has been convicted" appearing in a statute could attract a conviction had before the enactment of the statute. Their Lordships after referring to a particular statute, not in relation to time but as the present tense of logic, to express a hypothesis without regard to time, went on to observe that the verb, "has been" which they were construing expressed a hypothesis without regard to time, and, in the particular statute, meant only "shall have been". Their Lordships after referring to a particular statute, not in relation to time but as the present tense of logic, to express a hypothesis without regard to time, went on to observe that the verb, "has been" which they were construing expressed a hypothesis without regard to time, and, in the particular statute, meant only "shall have been". Their Lordships did not say that, "has been" could always be read as "shall have been" and if it had been contended that a past superseded conviction, no longer in force, could be attracted by the words, "has been convicted" there can be little doubt what their answer would have been". 7. The decision in Patna Improvement Trust v. Shrimati Lakshmi Devi and others ( AIR 1963 SC 1077 ) relied on by counsel also does not limitate against what we have said above regarding the interpretation to be placed on the explanation to sub-s.(4) of S.55 of the Act. The question that arose before the Supreme Court turned on the interpretation of a Clause in the schedule to the Bihar Town Planning and Improvement Trust Act 1951 which was in these terms: "C. 2 (1) "The first publication of a notice of an improvement scheme under S.46 of the Bihar Town Planning and Improvement Trust Act, 1951 (Bihar Act XXXV of 1951) shall be substituted for and have the same effect as publication in the official Gazette and in the locality of a notification under sub-s.(1) of S.4 of the said Act, except where a notification under sub-s.(1) of a S.4 or declaration under S.6 of the said Act has been previously made and is in force". The said Act is the Land Acquisition Act 1 of 1894 and in the case there was a notification under S.4 of that Act before the Bihar Town Planning and Improvement Trust Act was passed. By virtue of the provision just read it was provided that a publication under S.46 of that Act shall be substituted for and shall have the same effect as a notification under S.4 of the Land Acquisition Act. The contention that was raised was that the Bihar Act was applicable and that the notification under S.4 of the Land Acquisition Act shall have no effect and the Supreme Court held that this would be normally so. The contention that was raised was that the Bihar Act was applicable and that the notification under S.4 of the Land Acquisition Act shall have no effect and the Supreme Court held that this would be normally so. But the provision which we have read also carried an exception and by virtue of the exception the substitution of a notification under S.46 will occur only in such cases where there had not been notifications under sub-s.(1) of S.4 or declaration under S.6 of the Land Acquisition Act of 1894 at the time of the publication of the notice under the Bihar Act. The Supreme Court so held. This case has no relevance in understanding the words of the explanation. 8. The view taken in Ex. P9 that the petitioners were not probationers is in concordance with what we have stated above and therefore we dismiss this writ petition but direct the parties to bear their respective costs.