Important New Information:
All during my five-year research on Badges of the Bravest, the Brooklyn Historical Society museum and archive was closed for renovation. The building has since re-opened and the library should re-open soon. Unfortunately this meant that vital information on the Brooklyn Fire Department (my home town) was not accessible.
One piece of information that I have uncovered is documentation, in a City of Brooklyn Annual Report, that it was in 1882 that the equilateral cross badge was adopted AND that the previous badge was the clover-leaf badge. A newspaper article from the time indicates that the new badge is patterned after the emblem of the 6th Corps of the Union Army AND it refers to it as a Maltese cross. This is really a stretch since the 6th Corps emblem was clearly an equilateral cross. I believe this supports my contention, on pages 20 - 22, that the choice of the Maltese cross as a symbol for firefighters as first introduced in NYC in 1865 was based on its use by the military NOT any correlation to the Knights of St. John in Malta.
Another article appearing in the the June 15, 1866 issue of the Brooklyn Daily Eagle gives vivid details of the problem of too many people having fire badges in their possession. Although some 2,600 badges had been issued over the years, there were less than 1,500 active and exempt firemen on the rolls. It goes on to say that a badge "with a new pattern" will be designed and issued to all firemen so as to void the old badges.
Another design change for firemens' badges is documented in September 1873 but no details are given.
So that gives us three dates for badge changes in the Brooklyn Fire Department, 1866, 1873 and 1882.
In June 1884, a new Fire Lines badge was issued. While the earlier badge is not described, the new badge is described as being "in the form of a cross, with the arms of the city in the central medallion - the same as the department badges at the time. It also has the words "Brooklyn Dep't Fire" and in a scroll work plate the word "Press." A picture of one of these badges appears on page 72.