Whenever any member of the said fire insurance patrol has served 25 years or more in such patrol (the last 2 years of which shall have been continuous), has reached the age of 50 or 55, and is no longer in the service as a member of the fire insurance patrol, he shall be entitled to a monthly pension as follows:
(a) If he is age 50 or over but less than 55 and has retired or has been discharged for any cause, a monthly pension equal to 40% of the wages or salary received by him at the date of retirement or discharge;(b) If he is age 55 or over and has retired or has been discharged for any cause, a monthly pension equal to 50% of the wages or salary received by him at the date of retirement or discharge.