1. Any member of the fire department of any such city, village or incorporated town having served twenty-five years or more in such fire department, and having theretofore regularly paid into the pension fund his periodic payments as herein provided, shall be retired upon written application to the board of trustees, setting forth a time not less than thirty days nor more than sixty days after the filing of such application at which he desires to be retired. Thereupon, the board of trustees shall order and direct that said member shall be paid a monthly pension equal to fifty percent of the average monthly salary of said member during the twelve months immediately preceding the effective date of his retirement; and further provided that any member who remains on active duty in the fire department and continues to make regular and periodic payments into the pension fund as herein provided for a period of time beyond twenty-five years shall, upon subsequent retirement, be paid monthly an additional sum equal to one percent of the average monthly salary of said member during the twelve months immediately preceding the effective date of his retirement for each full twelve-month period beyond twenty-five years up to but not including the year in which said member attains the age of sixty-five.

2. Any member of the fire department of any such city, village or incorporated town having served at least twenty years, but less than twenty-five years, in such fire department, and having theretofore regularly paid into the pension fund his periodic payments as herein provided, may make application to be retired from such fire department, and if his application is granted by the board of trustees, the said board of trustees shall order and direct that said member shall be paid a monthly service pension equal to forty percent of the average monthly salary of said member during the twelve months immediately preceding the effective date of his retirement.

3. In the event that any member of the fire department of any such city, village or incorporated town having served twenty years or more in such fire department, and having theretofore regularly paid into the pension fund his periodic payments as herein provided, is discharged from such fire department, the board of trustees shall order and direct that said person shall be paid a monthly service pension equal to fifty percent of the salary said person was receiving at the time of his discharge, and further provided that the board of trustees shall order and direct the payment of said monthly service pension within thirty days after the date of discharge of said member, and the effective date of said pension shall be the same as the date of his discharge.

4. Members of volunteer fire departments serving without pay shall receive such monthly amount as may be fixed by the board of trustees.