In the said communication, which deals with the seniority of Artificers viz-a-viz non- Artificers, it is stated thus: - “The contention that seniority status of Artificers vis-a-vis non-artificers is ambiguous and unresolved is incorrect. The Regulation 247 of Reg Navy Part III and Navy Instruction 2/96 clearly lays down that the relative rank of Artificers 3rd/2nd/1st Class and Chief Artificers is that of a Chief Petty Officer.” Civil Appeal Nos. 6886-6887 of 2011 Page 5 of 98. This is the primary document on which the appellant is relying upon. The communication dated 16th November 2000 refers to the seniority status of Artificers vis-a-vis non- Artificers. It refers to Regulation 247. We have, therefore, perused Regulation 247. We may note here that Regulation 247 does not deal with equivalence. Clause (1) of Regulation 247 provides that the crews of Indian Naval Ships shall rank and command after Naval Cadets according to Regulation 247. Clauses (1) to (3) of Regulation 247 are