The firemen in question have therefore interpreted this provision as allowing them to use service elsewhere to qualify for the promotion exam given by their new employer. These two provisions must be read in the context of article 1269m in its entirety. The provisions of article 1269m do not apply to a city unless it adopts them, and it may choose to apply the provisions only to a Fire Department or only to a Police Department, section 27. The statute gives each city some freedom to design its own civil service plan. Article 1269m does not require these classifications to be uniform from city to city.
Some provisions suggest that the statute contemplates no statewide model for classifications.
Thus, classification plans in some but not all cities may be based on similarity of duties and responsibilities. Classification plans may vary as to the number of paygrades provided. When the legislature enacted article 1269m in 1947, Acts 1947, 50th Leg., ch. At that time, a fireman's two years' service under one classification plan could not be expected to fulfill the requirements of a different plan. 668 at 1972, and does not change the meaning of provisions enacted twenty years earlier.