Before we start examining the correctness of the rival contentions advanced on either side, it is appropriate that a detailed reference to the Rules is made in order to ascertain the scheme. 'Cadre ' has been defined in rule 2, sub rule (2) to mean the group of posts in the grades of Section Officer and Assistant in any of the Ministries or offices specified in col. 2 of the First Schedule and any of the offices specified against such Ministry or office in col. 3 of that Schedule. 'Cadre Officer ' in rule 2(g) in relation to the Section Officers ' grade or the Assistants ' grade means a member Of the service of the Section Officers ' grade or Assistants ' grade, as the case may be, and includes a temporary officer approved for long term appointment to that grade. 'Long term appointment ' means under rule 2(1) appointment for an indefinite period as different from a purely temporary or ad hoc appointment.